Recent Stanford Publications in PubMed
- Transfusion and coagulation management in major obstetric hemorrhage.Butwick AJ, Goodnough LTCurr Opin Anaesthesiol
- Macrophages in vascular inflammation - From atherosclerosis to vasculitis.Shirai T, Hilhorst M, Harrison DG, Goronzy JJ, Weyand CMAutoimmunity
- Multiplexed locus-specific analysis of DNA methylation in single cells.Cheow LF, Quake SR, Burkholder WF, Messerschmidt DMNat Protoc
- Counseling patients for lifestyle change: making a 15-minute office visit work.Berra K, Hughes SMenopause
- Variations in the Binding Pocket of an Inhibitor of the Bacterial Division Protein FtsZ across Genotypes and Species.Miguel A, Hsin J, Liu T, Tang G, Altman RB, Huang KCPLoS Comput Biol
- Basic Level Category Structure Emerges Gradually across Human Ventral Visual Cortex.Iordan MC, Greene MR, Beck DM, Fei-Fei LJ Cogn Neurosci
- Drug-Induced Thrombocytopenia following a Transvaginal Oocyte Retrieval for In Vitro Fertilization.Comstock IA, Longmire M, Aster RH, Milki AACase Rep Obstet Gynecol
- Activity-dependent regulation of prestin expression in mouse outer hair cells.Song Y, Xia A, Lee HY, Wang R, Ricci AJ, Oghalai JSJ Neurophysiol
- Harvest and Primary Culture of the Murine Aldosterone-Sensitive Distal Nephron.Labarca M, Nizar JM, Walczak EM, Dong W, Pao AC, Bhalla VAm J Physiol Renal Physiol
- Bartonellae are Prevalent and Diverse in Costa Rican Bats and Bat Flies.Judson SD, Frank HK, Hadly EAZoonoses Public Health
- Carl Djerassi (1923-2015).Zare RNAngew Chem Int Ed Engl
- Reduced field of view imaging using a static second-order gradient for functional MRI applications.Islam H, Glover GHMagn Reson Med
- Palladium-Catalyzed CH Activation of N-Allyl Imines: Regioselective Allylic Alkylations to Deliver Substituted Aza-1,3-Dienes.Trost BM, Mahapatra S, Hansen MAngew Chem Int Ed Engl
- Hybrid epicardial and endocardial ablation of atrial fibrillation: is ablation on two sides of the atrial wall better than one?Wang PJJ Am Heart Assoc
- Spectral snapshots of bacterial cell-wall composition and the influence of antibiotics by whole-cell NMR.Nygaard R, Romaniuk JA, Rice DM, Cegelski LBiophys J
- UNOS Regional Variations in Appeal Denial Rates with Non-Standard MELD/PELD Exceptions: Support for a National Review Board.Gish RG, Wong RJ, Honerkamp-Smith G, Xu R, Osorio RWClin Transplant
- Non-typhoidal Salmonella Typhimurium ST313 isolates that cause bacteremia in humans stimulate less inflammasome activation than ST19 isolates associated with gastroenteritis.Carden S, Okoro C, Dougan G, Monack DPathog Dis
- An anthropologically based model of the impact of asymptomatic cases on the spread of Neisseria gonorrhoeae.Hazel A, Marino S, Simon CJ R Soc Interface
- Serenity: Violence, Inequality, and Recovery on the Edge of Mexico City.Garcia AMed Anthropol Q
- Urine biomarkers for necrotizing enterocolitis.Sylvester KG, Moss RLPediatr Surg Int
- Availability of Alternatives and the Processing of Scalar Implicatures: A Visual World Eye-Tracking Study.Degen J, Tanenhaus MKCogn Sci
- Medical liability and reporting malpractice payments--reply.Mello MM, Studdert DM, Kachalia AJAMA
- In retrospect: a marine biologist's remarkable legacy.Albert S, Albert M, Kohrs DNature
- Adding insult to injury: discontinuous insurance following spine trauma.Kastenberg ZJ, Hurley MP, Weiser TG, Cole TS, Staudenmayer KL, Spain DA, Ratliff JKJ Bone Joint Surg Am
- Regional variation in antenatal corticosteroid use: a network-level quality improvement study.Profit J, Goldstein BA, Tamaresis J, Kan P, Lee HCPediatrics
- Research on medical practices and the ethics of disclosure.Magnus D, Wilfond BSPediatrics
- Prasugrel plus aspirin beyond 12 months is associated with improved outcomes after TAXUS Liberté paclitaxel-eluting coronary stent placement.Garratt KN, Weaver WD, Jenkins RG, Pow TK, Mauri L, Kereiakes DJ, Winters KJ, Christen T, Allocco DJ, Lee DPCirculation
- Closed-globe injuries of the ocular surface associated with combat blast exposure.Cockerham GC, Lemke S, Rice TA, Wang G, Glynn-Milley C, Zumhagen L, Cockerham KPOphthalmology
- Cigarette smoking is associated with a reduction in the risk of incident gout: results from the Framingham Heart Study original cohort.Wang W, Krishnan ERheumatology (Oxford)
- Special commentary: Food and Drug Administration and American Glaucoma Society co-sponsored workshop: the validity, reliability, and usability of glaucoma imaging devices.Meier KL, Greenfield DS, Hilmantel G, Kahook MY, Lin C, Rorer EM, Singh K, Tarver ME, Weinreb RN, Eydelman MB, Liebmann JMOphthalmology
- Pediatric glaucoma surgery: a report by the American Academy Of Ophthalmology.Chen TC, Chen PP, Francis BA, Junk AK, Smith SD, Singh K, Lin SCOphthalmology
Transfusion and coagulation management in major obstetric hemorrhage.
Curr Opin Anaesthesiol. 2015 Mar 25;
Authors: Butwick AJ, Goodnough LT
PURPOSE OF REVIEW: Major obstetric hemorrhage is a leading cause of maternal morbidity and mortality. We will review transfusion strategies and the value of monitoring the maternal coagulation profile during severe obstetric hemorrhage.
RECENT FINDINGS: Epidemiologic studies indicate that rates of severe postpartum hemorrhage (PPH) in well resourced countries are increasing. Despite these increases, rates of transfusion in obstetrics are low (0.9-2.3%), and investigators have questioned whether a predelivery 'type and screen' is cost-effective for all obstetric patients. Instead, blood ordering protocols specific to obstetric patients can reduce unnecessary antibody testing. When severe PPH occurs, a massive transfusion protocol has attracted interest as a key therapeutic resource by ensuring sustained availability of blood products to the labor and delivery unit. During early postpartum bleeding, recent studies have shown that hypofibrinogenemia is an important predictor for the later development of severe PPH. Point-of-care technologies, such as thromboelastography and rotational thromboelastometry, can identify decreased fibrin clot quality during PPH, which correlate with low fibrinogen levels.
SUMMARY: A massive transfusion protocol provides a key resource in the management of severe PPH. However, future studies are needed to assess whether formula-driven vs. goal-directed transfusion therapy improves maternal outcomes in women with severe PPH.
PMID: 25812005 [PubMed - as supplied by publisher]
Macrophages in vascular inflammation - From atherosclerosis to vasculitis.
Autoimmunity. 2015 Mar 26;:1-13
Authors: Shirai T, Hilhorst M, Harrison DG, Goronzy JJ, Weyand CM
The spectrum of vascular inflammatory disease ranges from atherosclerosis and hypertension, widespread conditions affecting large proportions of the population, to the vasculitides, rare syndromes leading to fast and irreversible organ failure. Atherosclerosis progresses over decades, inevitably proceeding through multiple phases of disease and causes its major complications when the vessel wall lesion ruptures, giving rise to lumen-occlusive atherothrombosis. Vasculitides of medium and large arteries progress rapidly, causing tissue ischemia through lumen-occlusive intimal hyperplasia. In both disease entities, macrophages play a decisive role in pathogenesis, but function in the context of other immune cells that direct their differentiation and their functional commitments. In atherosclerosis, macrophages are involved in the removal of lipids and tissue debris and make a critical contribution to tissue damage and wall remodeling. In several of the vasculitides, macrophages contribute to granuloma formation, a microstructural platform optimizing macrophage-T-cell interactions, antigen containment and inflammatory amplification. By virtue of their versatility and plasticity, macrophages are able to promote a series of pathogenic functions, ranging from the release of cytokines and enzymes, the production of reactive oxygen species, presentation of antigen and secretion of tissue remodeling factors. However, as short-lived cells that lack memory, macrophages are also amendable to reprogramming, making them promising targets for anti-inflammatory interventions.
PMID: 25811915 [PubMed - as supplied by publisher]
Multiplexed locus-specific analysis of DNA methylation in single cells.
Nat Protoc. 2015 Apr;10(4):619-631
Authors: Cheow LF, Quake SR, Burkholder WF, Messerschmidt DM
This protocol details a method for measuring the DNA methylation state of multiple target sites in single cells, otherwise known as single-cell restriction analysis of methylation (SCRAM). The basic steps include isolating and lysing single cells, digesting genomic DNA with a methylation-sensitive restriction endonuclease (MSRE) and amplification of multiple targets by two rounds of PCR to determine the methylation status of target sites. The method can reliably and accurately detect the methylation status of multiple target sites in each single cell, and it can be completed in a relatively short time (<2 d) at low cost. Consequently, the method may be preferable over whole-genome methods in applications requiring highly reliable and cost-effective coverage of specific target sites in all cells from a sample and in cases when the DNA methylation states of single CpG sites are representative of the methylation status of corresponding regions of interest.
PMID: 25811896 [PubMed - as supplied by publisher]
Counseling patients for lifestyle change: making a 15-minute office visit work.
Menopause. 2015 Apr;22(4):453-455
Authors: Berra K, Hughes S
Lifestyle counseling is an intervention that can improve chronic disease management as well as patient and provider satisfaction. Patients and providers are often frustrated with difficulties faced in the implementation and maintenance of lifestyle change. Can we change this paradigm? Are there new strategies that work and can be implemented in a typical office visit? The medical literature confirms the effectiveness of lifestyle interventions and recommends that lifestyle counseling be considered as a cornerstone of care. Here we present a case study of a midlife woman to show how motivational interviewing can be used to help her identify and meet her health goals.
PMID: 25811869 [PubMed - as supplied by publisher]
Variations in the Binding Pocket of an Inhibitor of the Bacterial Division Protein FtsZ across Genotypes and Species.
PLoS Comput Biol. 2015 Mar;11(3):e1004117
Authors: Miguel A, Hsin J, Liu T, Tang G, Altman RB, Huang KC
The recent increase in antibiotic resistance in pathogenic bacteria calls for new approaches to drug-target selection and drug development. Targeting the mechanisms of action of proteins involved in bacterial cell division bypasses problems associated with increasingly ineffective variants of older antibiotics; to this end, the essential bacterial cytoskeletal protein FtsZ is a promising target. Recent work on its allosteric inhibitor, PC190723, revealed in vitro activity on Staphylococcus aureus FtsZ and in vivo antimicrobial activities. However, the mechanism of drug action and its effect on FtsZ in other bacterial species are unclear. Here, we examine the structural environment of the PC190723 binding pocket using PocketFEATURE, a statistical method that scores the similarity between pairs of small-molecule binding sites based on 3D structure information about the local microenvironment, and molecular dynamics (MD) simulations. We observed that species and nucleotide-binding state have significant impacts on the structural properties of the binding site, with substantially disparate microenvironments for bacterial species not from the Staphylococcus genus. Based on PocketFEATURE analysis of MD simulations of S. aureus FtsZ bound to GTP or with mutations that are known to confer PC190723 resistance, we predict that PC190723 strongly prefers to bind Staphylococcus FtsZ in the nucleotide-bound state. Furthermore, MD simulations of an FtsZ dimer indicated that polymerization may enhance PC190723 binding. Taken together, our results demonstrate that a drug-binding pocket can vary significantly across species, genetic perturbations, and in different polymerization states, yielding important information for the further development of FtsZ inhibitors.
PMID: 25811761 [PubMed - as supplied by publisher]
Basic Level Category Structure Emerges Gradually across Human Ventral Visual Cortex.
J Cogn Neurosci. 2015 Mar 26;:1-29
Authors: Iordan MC, Greene MR, Beck DM, Fei-Fei L
Objects can be simultaneously categorized at multiple levels of specificity ranging from very broad ("natural object") to very distinct ("Mr. Woof"), with a mid-level of generality (basic level: "dog") often providing the most cognitively useful distinction between categories. It is unknown, however, how this hierarchical representation is achieved in the brain. Using multivoxel pattern analyses, we examined how well each taxonomic level (superordinate, basic, and subordinate) of real-world object categories is represented across occipitotemporal cortex. We found that, although in early visual cortex objects are best represented at the subordinate level (an effect mostly driven by low-level feature overlap between objects in the same category), this advantage diminishes compared to the basic level as we move up the visual hierarchy, disappearing in object-selective regions of occipitotemporal cortex. This pattern stems from a combined increase in within-category similarity (category cohesion) and between-category dissimilarity (category distinctiveness) of neural activity patterns at the basic level, relative to both subordinate and superordinate levels, suggesting that successive visual areas may be optimizing basic level representations.
PMID: 25811711 [PubMed - as supplied by publisher]
Drug-Induced Thrombocytopenia following a Transvaginal Oocyte Retrieval for In Vitro Fertilization.
Case Rep Obstet Gynecol. 2015;2015:890610
Authors: Comstock IA, Longmire M, Aster RH, Milki AA
Drug-induced immune thrombocytopenia has been associated with hundreds of medications and can lead to devastating consequences for the patient. We present a case of a healthy 33-year-old female undergoing in vitro fertilization who developed a severe drug-induced thrombocytopenia, petechiae, and a large hemoperitoneum after receiving Cefazolin antibiotic prophylaxis for a transvaginal oocyte retrieval. The patient was admitted to the intensive care unit for resuscitation with blood products. The presence of drug-dependent platelet antibodies to Cefazolin was confirmed serologically.
PMID: 25810935 [PubMed]
Activity-dependent regulation of prestin expression in mouse outer hair cells.
J Neurophysiol. 2015 Mar 25;:jn.00869.2014
Authors: Song Y, Xia A, Lee HY, Wang R, Ricci AJ, Oghalai JS
Prestin is a membrane protein necessary for outer hair cell (OHC) electromotility and normal hearing. Its regulatory mechanisms are unknown. Several mouse models of hearing loss demonstrate increased prestin, inspiring us to investigate how hearing loss might feedback onto OHCs. To test whether centrally-mediated feedback regulates prestin, we developed a novel model of inner hair cell (IHC) loss. Injection of diphtheria toxin (DT) into adult CBA mice produced significant loss of IHCs without affecting OHCs. Thus, DT-injected mice were deaf because they had no afferent auditory input despite OHCs continuing to receive normal auditory mechanical stimulation and have normal function. Patch clamp studies demonstrated no change in OHC prestin, indicating that loss of information transfer centrally did not alter prestin expression. To test whether local mechanical feedback regulates prestin, we used TectaC1509G mice, where the tectorial membrane is malformed and only some OHCs are stimulated. OHCs connected to the tectorial membrane had normal prestin levels whereas OHCs not connected to the tectorial membrane had elevated prestin levels, supporting an activity-dependent model. To test whether the endocochlear potential was necessary, we studied TectaC1509G mice during development. OHCs not connected to the tectorial membrane had lower than normal prestin levels before the onset of the endocochlear potential and higher than normal prestin levels after the onset of the endocochlear potential. Together, these data indicate that OHC prestin levels are regulated through local feedback that requires mechanoelectrical transduction currents. This adaptation may serve to compensate for variations in the local mechanical environment.
PMID: 25810486 [PubMed - as supplied by publisher]
Harvest and Primary Culture of the Murine Aldosterone-Sensitive Distal Nephron.
Am J Physiol Renal Physiol. 2015 Mar 25;:ajprenal.00668.2014
Authors: Labarca M, Nizar JM, Walczak EM, Dong W, Pao AC, Bhalla V
The aldosterone-sensitive distal nephron (ASDN) exhibits axial heterogeneity in structure and function from the distal convoluted tubule to the medullary collecting duct. Ion and water transport is primarily divided between the cortex and medulla of the ASDN, respectively. Transcellular transport in this segment is highly regulated in health and disease and is integrated across different cell types. We currently lack an inexpensive, high-yield, and tractable technique to harvest and culture cells for the study of gene expression and physiologic properties of mouse cortical ASDN. To address this need, we harvested tubules bound to Dolichos biflorus agglutinin (DBA) lectin-coated magnetic beads from kidney cortex and characterized these cell preparations. We determined that these cells are enriched for markers of distal convoluted tubule, connecting tubule, and cortical collecting duct, including principal and intercalated cells. In primary culture these cells develop polarized monolayers with high-resistance (1000-1500 Ω*cm(2)), and maintain expression and activity of key channels. These cells demonstrate an amiloride-sensitive short-circuit current that can be enhanced with aldosterone and maintain measurable potassium and anion secretion. Our method can be easily adopted to study the biology of the ASDN and to investigate phenotypic differences between wild-type and transgenic mouse models.
PMID: 25810438 [PubMed - as supplied by publisher]
Bartonellae are Prevalent and Diverse in Costa Rican Bats and Bat Flies.
Zoonoses Public Health. 2015 Mar 23;
Authors: Judson SD, Frank HK, Hadly EA
Species in the bacterial genus, Bartonella, can cause disease in both humans and animals. Previous reports of Bartonella in bats and ectoparasitic bat flies suggest that bats could serve as mammalian hosts and bat flies as arthropod vectors. We compared the prevalence and genetic similarity of bartonellae in individual Costa Rican bats and their bat flies using molecular and sequencing methods targeting the citrate synthase gene (gltA). Bartonellae were more prevalent in bat flies than in bats, and genetic variants were sometimes, but not always, shared between bats and their bat flies. The detected bartonellae genetic variants were diverse, and some were similar to species known to cause disease in humans and other mammals. The high prevalence and sharing of bartonellae in bat flies and bats support a role for bat flies as a potential vector for Bartonella, while the genetic diversity and similarity to known species suggest that bartonellae could spill over into humans and animals sharing the landscape.
PMID: 25810119 [PubMed - as supplied by publisher]
Carl Djerassi (1923-2015).
Angew Chem Int Ed Engl. 2015 Mar 25;
Authors: Zare RN
Carl Djerassi died at the age of 91 on January 30, 2015. He is best known for developing the synthetic hormone used to the present day in the oral contraceptive commonly known as The Pill. Djerassi's other achievements include the use of mass spectrometry in organic chemistry, and extensive research on antibiotics and marine natural products. He was also an author of plays, poems, and short stories, including Oxygen, written together with Roald Hoffmann.
PMID: 25809781 [PubMed - as supplied by publisher]
Reduced field of view imaging using a static second-order gradient for functional MRI applications.
Magn Reson Med. 2015 Mar 25;
Authors: Islam H, Glover GH
PURPOSE: Imaging using reduced FOV excitation allows higher resolution or signal-to-noise ratio (SNR) per scan time but often requires long radiofrequency pulses. The goal of this study was to improve a recent reduced field of view (FOV) method that uses a second-order shim gradient to decrease pulse length and evaluate its use in functional MRI (fMRI) applications.
THEORY AND METHODS: The method, which was initially limited to excite thin disc-shaped regions at the isocenter, was extended to excite thicker regions off the isocenter and produced accurate excitation profiles on a grid phantom. Visual stimulation fMRI scans were performed with full and reduced FOV. The resolution of the time series images and functional activation maps were assessed using the full-width half-maxima of the autocorrelation functions (FACFs) of the noise images and the activation map values, respectively.
RESULTS: The resolution was higher in the reduced FOV time series images (4.1% ± 3.7% FACF reduction, P < 0.02) and functional activation maps (3.1% ± 3.4% FACF reduction, P < 0.01), but the SNR was lower (by 26.5% ± 16.9%). However, for a few subjects, the targeted region could not be localized to the reduced FOV due to the low Z2 gradient strength.
CONCLUSION: The results of this study suggest that the proposed method is feasible, though it would benefit from a stronger gradient coil. Magn Reson Med, 2015. © 2015 Wiley Periodicals, Inc.
PMID: 25809723 [PubMed - as supplied by publisher]
Palladium-Catalyzed CH Activation of N-Allyl Imines: Regioselective Allylic Alkylations to Deliver Substituted Aza-1,3-Dienes.
Angew Chem Int Ed Engl. 2015 Mar 24;
Authors: Trost BM, Mahapatra S, Hansen M
A new mode of activation of an imine via a rare aza-substituted π-allyl complex is described. Palladium-catalyzed C(sp(3) )H activation of the N-allyl imine and the subsequent nucleophilic attack by the α-alkyl cyanoester produced the 1-aza-1,3-diene as the sole regioisomer. In contrast, nucleophilic attack by the α-aryl cyanoester exclusively delivered the 2-aza-1,3-diene, which was employed in an inverse-electron-demand Diels-Alder reaction for heterobiaryl synthesis.
PMID: 25809660 [PubMed - as supplied by publisher]
Hybrid epicardial and endocardial ablation of atrial fibrillation: is ablation on two sides of the atrial wall better than one?
J Am Heart Assoc. 2015;4(3)
Authors: Wang PJ
PMID: 25809549 [PubMed - in process]
Spectral snapshots of bacterial cell-wall composition and the influence of antibiotics by whole-cell NMR.
Biophys J. 2015 Mar 24;108(6):1380-9
Authors: Nygaard R, Romaniuk JA, Rice DM, Cegelski L
Gram-positive bacteria surround themselves with a thick cell wall that is essential to cell survival and is a major target of antibiotics. Quantifying alterations in cell-wall composition are crucial to evaluating drug modes of action, particularly important for human pathogens that are now resistant to multiple antibiotics such as Staphylococcus aureus. Macromolecular and whole-cell NMR spectroscopy allowed us to observe the full panel of carbon and nitrogen pools in S. aureus cell walls and intact whole cells. We discovered that one-dimensional (13)C and (15)N NMR spectra, together with spectroscopic selections based on dipolar couplings as well as two-dimensional spin-diffusion measurements, revealed the dramatic compositional differences between intact cells and cell walls and allowed the identification of cell-wall signatures in whole-cell samples. Furthermore, the whole-cell NMR approach exhibited the sensitivity to detect distinct compositional changes due to treatment with the antibiotics fosfomycin (a cell-wall biosynthesis inhibitor) and chloramphenicol (a protein synthesis inhibitor). Whole cells treated with fosfomycin exhibited decreased peptidoglycan contributions while those treated with chloramphenicol contained a higher percentage of peptidoglycan as cytoplasmic protein content was reduced. Thus, general antibiotic modes of action can be identified by profiling the total carbon pools in intact whole cells.
PMID: 25809251 [PubMed - in process]
UNOS Regional Variations in Appeal Denial Rates with Non-Standard MELD/PELD Exceptions: Support for a National Review Board.
Clin Transplant. 2015 Mar 23;
Authors: Gish RG, Wong RJ, Honerkamp-Smith G, Xu R, Osorio RW
Although it has been generally recognized that there are inconsistencies among Regional Review Boards in the assignment of points for MELD/PELD exception patients with resulting considerable variation in appeal denial rates, data to actually prove this has been limited. We reviewed 6,533 MELD/PELD exception applications submitted between 2005 and 2008, calculated the variation in approval/denial rates, and followed these cases through mid-2013 to assess the effects on patient outcomes. We found highly significant regional variations in denial rates for appeals by exception patients and in transplantation rates. The odds of transplant for patients whose appeals are approved is 2.45 times that of patients not approved; that this effect does not vary by region suggests that the variation in transplant rates is driven, at least in part, by the variation in appeal denial rates. Health deterioration or death account for more than two-thirds of wait list removals among patients removed for reasons other than transplant. Our findings add to the weight of evidence that a national review board that uses current clinical expertise, peer review literature, and data to consistently assign priority could reduce regional inequities and move toward equitable allocation of organs and compliance with the HHS Final Rule. This article is protected by copyright. All rights reserved.
PMID: 25808918 [PubMed - as supplied by publisher]
Non-typhoidal Salmonella Typhimurium ST313 isolates that cause bacteremia in humans stimulate less inflammasome activation than ST19 isolates associated with gastroenteritis.
Pathog Dis. 2014 Dec 24;
Authors: Carden S, Okoro C, Dougan G, Monack D
Salmonella is an enteric pathogen that causes a range of diseases in humans. Non-typhoidal Salmonella (NTS) serovars such as Salmonella enterica serovar Typhimurium generally cause a self-limiting gastroenteritis whereas typhoidal serovars cause a systemic disease, typhoid fever. However, S. Typhimurium isolates within the multi-locus sequence type ST313 that commonly cause bacteremia in humans have emerged in sub-Saharan Africa as a major cause of bacteremia in humans. S. Typhimurium ST313 are phylogenetically distinct from classical S. Typhimurium lineages such as ST19 that cause zoonotic gastroenteritis worldwide. Previous studies have shown that the ST313 lineage has undergone genome degradation when compared to the ST19 lineage, similar to that observed for typhoidal serovars. Currently, little is known about phenotypic differences between ST313 isolates and other NTS isolates. We find that representative ST313 isolates invade non-phagocytic cells less efficiently than the classical ST19 isolates that are more commonly associated with gastroenteritis. In addition, ST313 isolates induce less Caspase- 1- dependent macrophage death and IL-1β release than ST19 isolates. ST313 isolates also express relatively lower levels of mRNA of the genes encoding the SPI-1 effector sopE2 and the flagellin, fliC, providing possible explanations for the decrease in invasion and inflammasome activation. The ST313 isolates have invasion and inflammatory phenotypes that are intermediate; more invasive and inflammatory than Salmonella enterica serovar Typhi and less than ST19 isolates associated with gastroenteritis. This suggests that both phenotypically and at the genomic level ST313 isolates are evolving signatures that facilitate a systemic lifestyle in humans.
PMID: 25808600 [PubMed - as supplied by publisher]
An anthropologically based model of the impact of asymptomatic cases on the spread of Neisseria gonorrhoeae.
J R Soc Interface. 2015 May 6;12(106)
Authors: Hazel A, Marino S, Simon C
Neisseria gonorrhoeae (GC) remains a serious burden in many high-sexual-activity, undertreated populations. Using empirical data from a 2009 study of GC burden among pastoralists in Kaokoveld, Namibia, we expand the standard gonorrhoea transmission model by using locally derived sexual contact data to explore transmission dynamics in a population with high rates of partner exchange and low treatment-seeking behaviour. We use the model to generate ball-park estimates for transmission probabilities and other parameter values for low-level (i.e. less than approx. 1200 copies/20 µl PCR reaction) asymptomatic infections, which account for 74% of all GC infections found in Kaokoveld in 2009, and to describe the impact of asymptomatic, low-level infections on overall prevalence patterns. Our results suggest that GC transmission probabilities are higher than previously estimated, that untreated infections take longer to clear than previously estimated and that a high prevalence of low-level infections is partially due to larger numbers of untreated, asymptomatic infections. These results provide new insights into the natural history of GC and the challenge of syndromic management programmes for the eradication of endemic gonorrhoea.
PMID: 25808340 [PubMed - in process]
Serenity: Violence, Inequality, and Recovery on the Edge of Mexico City.
Med Anthropol Q. 2015 Mar 23;
Authors: Garcia A
Over the last decade, there has been a sharp increase in drug addiction in Mexico, especially among the urban poor. During the same period, unregulated residential treatment centers for addiction, known as anexos, have proliferated throughout the country. These centers are utilized and run by marginalized populations and are widely known to engage in physical violence. Based on long-term ethnographic research in Mexico City, this article describes why anexos emerged, how they work, and what their prevalence and practices reveal about the nature of recovery in a context where poverty, drugs, and violence are existential realities. Drawing attention to the dynamic relationship between violence and recovery, pain, and healing, it complicates categories of violence and care that are presumed to have exclusive meaning, illuminating the divergent meanings of, and opportunities for, recovery, and how these are socially configured and sustained. [addiction, violence, Mexico, drug war, informality] This article is protected by copyright. All rights reserved.
PMID: 25808246 [PubMed - as supplied by publisher]
Urine biomarkers for necrotizing enterocolitis.
Pediatr Surg Int. 2015 Mar 26;
Authors: Sylvester KG, Moss RL
Necrotizing enterocolitis (NEC) remains a significant cause of morbidity and mortality in premature neonates. Despite decades of investigation, treating clinicians are still not able to determine which premature infants are at greatest risk of developing NEC and which of the affected infants will develop severe NEC requiring operation. A biomarker is a specific molecular indicator that can be used to identify or measure the progress of a disease. Many potential biomarkers have been studied for their potential relevance to NEC. Those showing promise include C-reactive protein, intestinal fatty acid-binding protein, platelet-activating factor and many others. None to date have achieved sufficient predictive value to be clinically useful. Distinguishing between the specific changes in NEC and the non-specific inflammation of sepsis has proven challenging. Urine is a particularly attractive site for potential biomarkers. It can be collected readily and non-invasively, and it is a rich source of both proteins and peptides. Preliminary work has revealed some promising biomarkers of NEC in urine. Combined with clinical data, they have been shown to be highly predictive in small series of patients. Advances in high-throughput molecular analysis have opened the door to finding biomarkers that may meaningfully improve the outcome of infants at risk for NEC.
PMID: 25807901 [PubMed - as supplied by publisher]
Availability of Alternatives and the Processing of Scalar Implicatures: A Visual World Eye-Tracking Study.
Cogn Sci. 2015 Mar 25;
Authors: Degen J, Tanenhaus MK
Two visual world experiments investigated the processing of the implicature associated with some using a "gumball paradigm." On each trial, participants saw an image of a gumball machine with an upper chamber with orange and blue gumballs and an empty lower chamber. Gumballs dropped to the lower chamber, creating a contrast between a partitioned set of gumballs of one color and an unpartitioned set of the other. Participants then evaluated spoken statements, such as "You got some of the blue gumballs." Experiment 1 investigated the time course of the pragmatic enrichment from some to not all when the only utterance alternatives available to refer to the different sets were some and all. In Experiment 2, the number terms two, three, four, and five were also included in the set of alternatives. Scalar implicatures were delayed relative to the interpretation of literal statements with all only when number terms were available. The results are interpreted as evidence for a constraint-based account of scalar implicature processing.
PMID: 25807866 [PubMed - as supplied by publisher]
Medical liability and reporting malpractice payments--reply.
JAMA. 2015 Mar 10;313(10):1058-9
Authors: Mello MM, Studdert DM, Kachalia A
PMID: 25756448 [PubMed - indexed for MEDLINE]
In retrospect: a marine biologist's remarkable legacy.
Nature. 2015 Mar 5;519(7541):33
Authors: Albert S, Albert M, Kohrs D
PMID: 25739623 [PubMed - indexed for MEDLINE]
Adding insult to injury: discontinuous insurance following spine trauma.
J Bone Joint Surg Am. 2015 Jan 21;97(2):141-6
Authors: Kastenberg ZJ, Hurley MP, Weiser TG, Cole TS, Staudenmayer KL, Spain DA, Ratliff JK
BACKGROUND: Spine trauma patients may represent a group for whom insurance fails to provide protection from catastrophic medical expenses, resulting in the transfer of financial burden onto individual families and public payers. This study compares the rate of insurance discontinuation for patients who underwent surgery for traumatic spine injury with and without spinal cord injury with the rate for matched control subjects.
METHODS: We used the MarketScan database to perform a retrospective cohort study of privately insured spine trauma patients who underwent surgery from 2006 to 2010. Kaplan-Meier survival analysis was used to assess the time to insurance discontinuation. Cox proportional-hazards regression was used to determine hazard ratios for insurance discontinuation among spine trauma patients compared with the matched control population.
RESULTS: The median duration of existing insurance coverage was 20.2 months for those with traumatic spinal cord injury, 25.6 months for those with traumatic spine injury without spinal cord injury, and 48.0 months for the matched control cohort (log-rank p < 0.0001). After controlling for multiple covariates, the hazard ratios for discontinuation of insurance were 2.02 (95% CI [confidence interval], 1.83 to 2.23) and 2.78 (95% CI, 2.31 to 3.35) for the trauma patients without and with spinal cord injury, respectively, compared with matched controls.
CONCLUSIONS: Rates of insurance discontinuation are significantly higher for trauma patients with severe spine injury compared with the uninjured population, indicating that patients with disabling injuries are at increased risk for loss of insurance coverage.
PMID: 25609441 [PubMed - indexed for MEDLINE]
Regional variation in antenatal corticosteroid use: a network-level quality improvement study.
Pediatrics. 2015 Feb;135(2):e397-404
Authors: Profit J, Goldstein BA, Tamaresis J, Kan P, Lee HC
BACKGROUND AND OBJECTIVES: Examination of regional care patterns in antenatal corticosteroid use (ACU) rates may be salient for the development of targeted interventions. Our objective was to assess network-level variation using California perinatal care regions as a proxy. We hypothesized that (1) significant variation in ACU exists within and between California perinatal care regions, and (2) lower performing regions exhibit greater NICU-level variability in ACU than higher performing regions.
METHODS: We undertook cross-sectional analysis of 33,610 very low birth weight infants cared for at 120 hospitals in 11 California perinatal care regions from 2005 to 2011. We computed risk-adjusted median ACU rates and interquartile ranges (IQR) for each perinatal care region. The degree of variation was assessed using hierarchical multivariate regression analysis with NICU as a random effect and region as a fixed effect.
RESULTS: From 2005 to 2011, mean ACU rates across California increased from 82% to 87.9%. Regional median (IQR) ACU rates ranged from 68.4% (24.3) to 92.9% (4.8). We found significant variation in ACU rates among regions (P < .0001). Compared with Level IV NICUs, care in a lower level of care was a strongly significant predictor of lower odds of receiving antenatal corticosteroids in a multilevel model (Level III, 0.65 [0.45-0.95]; Level II, 0.39 [0.24-0.64]; P < .001). Regions with lower performance in ACU exhibited greater variability in performance.
CONCLUSIONS: We found significant variation in ACU rates among California perinatal regions. Regional quality improvement approaches may offer a new avenue to spread best practice.
PMID: 25601974 [PubMed - indexed for MEDLINE]
Research on medical practices and the ethics of disclosure.
Pediatrics. 2015 Feb;135(2):208-10
Authors: Magnus D, Wilfond BS
PMID: 25583909 [PubMed - indexed for MEDLINE]
Prasugrel plus aspirin beyond 12 months is associated with improved outcomes after TAXUS Liberté paclitaxel-eluting coronary stent placement.
Circulation. 2015 Jan 6;131(1):62-73
Authors: Garratt KN, Weaver WD, Jenkins RG, Pow TK, Mauri L, Kereiakes DJ, Winters KJ, Christen T, Allocco DJ, Lee DP
BACKGROUND: The TAXUS Liberté Post Approval Study (TL-PAS) contributed patients treated with TAXUS Liberté paclitaxel-eluting stent and prasugrel to the Dual Antiplatelet Therapy Study (DAPT) that compared 12 and 30 months thienopyridine plus aspirin therapy after drug-eluting stents.
METHODS AND RESULTS: Outcomes for 2191 TL-PAS patients enrolled into DAPT were assessed. The DAPT coprimary composite end point (death, myocardial infarction [MI], or stroke) was lower with 30 compared with 12 months prasugrel treatment (3.7% versus 8.8%; hazard ratio [HR], 0.407; P<0.001). Rates of death and stroke were similar between groups, but MI was significantly reduced with prolonged prasugrel treatment (1.9% versus 7.1%; HR, 0.255; P<0.001). The DAPT coprimary end point, stent thrombosis, was also lower with longer therapy (0.2% versus 2.9%; HR, 0.063; P<0.001). MI related to stent thrombosis (0% versus 2.6%; P<0.001) and occurring spontaneously (1.9% versus 4.5%; HR, 0.407; P=0.007) were both reduced with prolonged prasugrel. MI rates increased within 90 days of prasugrel cessation after both 12 and 30 months treatment. Composite Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Coronary Arteries (GUSTO) moderate or severe bleeds were modestly increased (2.4% versus 1.7%; HR, 1.438; P=0.234) but severe bleeds were not more frequent (0.3% versus 0.5%; HR, 0.549; P=0.471) in the prolonged treatment group.
CONCLUSIONS: Prasugrel and aspirin continued for 30 months reduced ischemic events for the TAXUS Liberté paclitaxel-eluting stent patient subset from DAPT through reductions in MI and stent thrombosis. Withdrawal of prasugrel was followed by an increase in MI after both 12 and 30 months therapy. The optimal duration of dual antiplatelet therapy with prasugrel after TAXUS Liberté paclitaxel-eluting stent remains unknown, but appears to be >30 months.
CLINICAL TRIAL REGISTRATION URL: http://www.clinicaltrials.gov. Unique identifier: NCT00997503.
PMID: 25400062 [PubMed - indexed for MEDLINE]
Closed-globe injuries of the ocular surface associated with combat blast exposure.
Ophthalmology. 2014 Nov;121(11):2165-72
Authors: Cockerham GC, Lemke S, Rice TA, Wang G, Glynn-Milley C, Zumhagen L, Cockerham KP
PURPOSE: To describe closed-globe conjunctival and corneal injuries and endothelial cell abnormalities associated with blast exposure and their relationships to other closed-globe injuries and blast-event characteristics.
DESIGN: Observational cross-sectional study.
PARTICIPANTS: Veterans with a history of blast-related traumatic brain injury (TBI).
METHODS: History and ocular examination, including slit-lamp biomicroscopy, gonioscopy, specular microscopy.
MAIN OUTCOME MEASURES: Type and location of blast injuries to the conjunctiva and cornea.
RESULTS: Ocular surface injuries were present in 25% (16 of 65) of blast-exposed veterans with TBI. Injuries included partial-thickness anterior stromal corneal scars (15 eyes), Descemet membrane ruptures (6 eyes), and conjunctival or corneal foreign bodies (7 eyes). Based on normative information from an age-matched comparison group, endothelial cell abnormalities were identified in 37% of participants. Eyes with ocular surface injury were more likely to have lower endothelial cell density, higher coefficient of variation of cell area, and lower percentage of hexagonal cells compared with eyes without injury. Presence of ocular surface injury or endothelial cell abnormalities was associated with elevated rates of other anterior and posterior segment injuries, as well as impairment of visual acuity. We found no relationship between ballistic eyewear use or severity level of TBI and presence of ocular surface injuries from blast.
CONCLUSIONS: Independent of TBI severity or use of protective eyewear, ocular surface injuries and endothelial cell abnormalities were found in significant numbers of veterans with blast-related brain injury. Descemet membrane ruptures from blast exposure were described. Ocular surface trauma was associated with other ocular injuries throughout the globe. Potential mechanisms for the types and locations of ocular injuries seen were discussed. Any corneal or conjunctival injury in a blast survivor should prompt a thorough ocular trauma examination, including gonioscopy and specular microscopy, with appropriate follow-up for associated injuries. Longitudinal studies are required to determine long-term visual outcomes after blast exposure.
PMID: 25124272 [PubMed - indexed for MEDLINE]
Cigarette smoking is associated with a reduction in the risk of incident gout: results from the Framingham Heart Study original cohort.
Rheumatology (Oxford). 2015 Jan;54(1):91-5
Authors: Wang W, Krishnan E
OBJECTIVE: Cigarette smoking is correlated with other risk factors for gout such as adiposity and alcohol intake. The goal of this study was to study the direction and magnitude of association between cigarette smoking and risk for gout.
METHODS: We analysed 54-year follow-up data (1948-2002) for 2279 men and 2785 women who were gout-free at their first assessment as a part of the Framingham Heart Study. Using Cox proportional hazards models we estimated the association between cigarette smoking and incident gout among men and women separately after adjusting for age, BMI, alcohol intake, hypertension, kidney disease and diabetes.
RESULTS: There were 399 incident cases (249 men and 150 women) of gout over 151 058 person-years of observation. Incidence rates of gout per 1000 person-years for smokers and non-smokers were 2.13 (95% CI 1.79, 2.53) and 3.04 (95% CI 2.70, 3.42), respectively. In multivariable Cox models, cigarette smoking was associated with gout with a hazard ratio of 0.76 (95% CI 0.59, 0.98) overall, 0.68 (95% CI 0.49, 0.93) among men and 0.92 (95% CI 0.60, 1.41) among women. Lower risk for smokers was evident among all obesity categories, but not among women. Sensitivity analysis suggested that the magnitude of the true odds ratio might be lower than our calculations.
CONCLUSION: Cigarette smoking is associated with lower incidence of gout and this is not explained by differences in the prevalence of risk factors. The mechanistic underpinnings of this epidemiological finding merits further study.
PMID: 25086327 [PubMed - indexed for MEDLINE]
Special commentary: Food and Drug Administration and American Glaucoma Society co-sponsored workshop: the validity, reliability, and usability of glaucoma imaging devices.
Ophthalmology. 2014 Nov;121(11):2116-23
Authors: Meier KL, Greenfield DS, Hilmantel G, Kahook MY, Lin C, Rorer EM, Singh K, Tarver ME, Weinreb RN, Eydelman MB, Liebmann JM
PMID: 25085628 [PubMed - indexed for MEDLINE]
Pediatric glaucoma surgery: a report by the American Academy Of Ophthalmology.
Ophthalmology. 2014 Nov;121(11):2107-15
Authors: Chen TC, Chen PP, Francis BA, Junk AK, Smith SD, Singh K, Lin SC
OBJECTIVE: To review the current published literature to evaluate the success rates and long-term problems associated with surgery for pediatric glaucoma.
METHODS: Literature searches of the PubMed and Cochrane Library databases were last conducted in May 2012. The search yielded 838 potentially relevant citations, of which 273 were in non-English languages. The titles and abstracts of these articles were reviewed by the authors, and 364 were selected for possible further review. Members of the Ophthalmic Technology Assessment Committee Glaucoma Panel reviewed the full text of these articles and used the 36 that met inclusion and exclusion criteria for this Ophthalmic Technology Assessment. There were no studies on the topic that provided level I evidence. The assessment included only level II and level III studies.
RESULTS: Surgeons treat pediatric glaucoma most commonly with goniotomy, trabeculotomy, trabeculectomy, combined trabeculotomy and trabeculectomy, tube shunt surgery, cyclodestruction, and deep sclerectomy. Certain surgical options seem better for specific diagnoses, such as primary congenital glaucoma, aphakic glaucoma, and glaucomas associated with other ocular or systemic anomalies.
CONCLUSIONS: There are many surgical options for the treatment of the pediatric glaucomas. The relative efficacy of these various procedures for particular diagnoses and clinical situations should be weighed against the specific risks associated with the procedures for individual patients.
PMID: 25066765 [PubMed - indexed for MEDLINE]
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