Life-cycle-coupled evolution of mitosis in close relatives of animals.

Eukaryotes have evolved towards one of two extremes along a spectrum of strategies for remodelling the nuclear envelope during cell division: disassembling the nuclear envelope in an open mitosis or constructing an intranuclear spindle in a closed mitosis1,2. Both classes of mitotic remodelling involve key differences in the core division machinery but the evolutionary reasons for adopting a specific mechanism are unclear. Here we use an integrated comparative genomics and ultrastructural imaging approach to investigate mitotic strategies in Ichthyosporea, close relatives of animals and fungi. We show that species in this clade have diverged towards either a fungal-like closed mitosis or an animal-like open mitosis, probably to support distinct multinucleated or uninucleated states. Our results indicate that multinucleated life cycles favour the evolution of closed mitosis.

Adaptive Health Technology Assessment: A Scoping Review of Methods.

OBJECTIVES: Health technology assessment (HTA) is an established mechanism for explicit priority setting to support universal health coverage. However, full HTA requires significant time, data, and capacity for each intervention, which limits the number of decisions it can inform. Another approach systematically adapts full HTA methods by leveraging HTA evidence from other settings. We call this "adaptive" HTA (aHTA), although in settings where time is the main constraint, it is also called "rapid HTA." METHODS: The objectives of this scoping review were to identify and map existing aHTA methods, and to assess their triggers, strengths, and weaknesses. This was done by searching HTA agencies' and networks' websites, and the published literature. Findings have been narratively synthesized. RESULTS: This review identified 20 countries and 1 HTA network with aHTA methods in the Americas, Europe, Africa, and South-East Asia. These methods have been characterized into 5 types: rapid reviews, rapid cost-effectiveness analyses, rapid manufacturer submissions, transfers, and de facto HTA. Three characteristics "trigger" the use of aHTA instead of full HTA: urgency, certainty, and low budget impact. Sometimes, an iterative approach to selecting methods guides whether to do aHTA or full HTA. aHTA was found to be faster and more efficient, useful for decision makers, and to reduce duplication. Nevertheless, there is limited standardization, transparency, and measurement of uncertainty. CONCLUSIONS: aHTA is used in many settings. It has potential to improve the efficiency of any priority-setting system, but needs to be better formalized to improve uptake, particularly for nascent HTA systems.

Essential emergency and critical care as a health system response to critical illness and the COVID19 pandemic: what does it cost?

Essential Emergency and Critical Care (EECC) is a novel approach to the care of critically ill patients, focusing on first-tier, effective, low-cost, life-saving care and designed to be feasible even in low-resourced and low-staffed settings. This is distinct from advanced critical care, usually conducted in ICUs with specialised staff, facilities and technologies. This paper estimates the incremental cost of EECC and advanced critical care for the planning of care for critically ill patients in Tanzania and Kenya.The incremental costing took a health systems perspective. A normative approach based on the ingredients defined through the recently published global consensus on EECC was used. The setting was a district hospital in which the patient is provided with the definitive care typically provided at that level for their condition. Quantification of resource use was based on COVID-19 as a tracer condition using clinical expertise. Local prices were used where available, and all costs were converted to USD2020.The costs per patient day of EECC is estimated to be 1 USD, 11 USD and 33 USD in Tanzania and 2 USD, 14 USD and 37 USD in Kenya, for moderate, severe and critical COVID-19 patients respectively. The cost per patient day of advanced critical care is estimated to be 13 USD and 294 USD in Tanzania and USD 17 USD and 345 USD in Kenya for severe and critical COVID-19 patients, respectively.EECC is a novel approach for providing the essential care to all critically ill patients. The low costs and lower tech approach inherent in delivering EECC mean that EECC could be provided to many and suggests that prioritizing EECC over ACC may be a rational approach when resources are limited.

Protein-based inheritance.

Epigenetic mechanisms of inheritance have come to occupy a prominent place in our understanding of living systems, primarily eukaryotes. There has been considerable and lively discussion of the possible evolutionary significance of transgenerational epigenetic inheritance. One particular type of epigenetic inheritance that has not figured much in general discussions is that based on conformational changes in proteins, where proteins with altered conformations can act as templates to propagate their own structure. An increasing number of such proteins - prions and prion-like - are being discovered. Phenotypes due to the structurally altered proteins are transmitted along with their structures. This review discusses the properties and implications of "classical" amyloid-forming prions, as well as the broader class of proteins with intrinsically disordered domains, which are proving to have fascinating properties that appear to play important roles in cell organisation and function, especially during stress responses.

Physical Activity Coaching via Telehealth for People With Parkinson Disease: A Cohort Study.

BACKGROUND AND PURPOSE: Physical activity (PA) has many known benefits for people with Parkinson disease (PD); however, many people do not meet recommended levels of frequency or intensity. We designed Engage-PD, a PA coaching program delivered via telehealth and grounded in self-determination theory to promote PA uptake and facilitate exercise self-efficacy in people with Parkinson disease. This study aimed to determine the feasibility and preliminary efficacy of Engage-PD, and to explore whether baseline characteristics were associated with outcomes. METHODS: A single cohort of people with PD (n = 62, Hoehn and Yahr I-III) participated in the 3-month Engage-PD program, which consisted of up to 5 telehealth coaching sessions delivered by physical therapists. Feasibility was evaluated based on recruitment and retention rates, along with participants' feedback. Planned and unplanned PA, exercise self-efficacy (ESE), and individualized goals were assessed pre- and post-intervention. Relationships between baseline characteristics and changes in planned PA and ESE were also evaluated. RESULTS: Recruitment (62%) and retention (85%) rates were high, and the intervention was well accepted and perceived by the participants. From pre- to postintervention, participants increased planned PA (d = 0.33), ESE (d = 1.20), and individualized goal performance (d = 1.63) and satisfaction (d = 1.70). Participants with lower baseline planned PA experienced greater improvements in planned PA, and those with lower baseline ESE experienced greater improvements in ESE. DISCUSSION AND CONCLUSIONS: A telehealth PA coaching program for people with PD was feasible and potentially efficacious. Physical therapist-led coaching may be an important component of a consultative model of care starting early in the disease process.Video Abstract available for more insights from the authors (see the Video, Supplemental Digital Content 1, available at: http://links.lww.com/JNPT/A393).

Chronic venous disease. Part 1: pathophysiology and clinical features.

Chronic venous disease (CVD) is a commonly encountered condition in the dermatology outpatient department. If untreated, CVD may progress to chronic leg ulcer causing serious morbidity to the patient. It also affects the quality of life of the affected patient and contributes to loss of work productivity. The spectrum of clinical manifestations for CVD is myriad, ranging from asymptomatic varicose veins and pigmentation to ulceration and scarring. Awareness of spectrum of clinical presentations is required to identify, diagnose and manage CVD. Long-standing cases may develop ankle joint stiffness, fixed flexion deformity, periostitis and even Marjolin ulcer. Increased venous hypertension, thought to result from valve incompetence and failure of the calf muscle pump, is central to the pathophysiology of the development of CVD. Tissue oedema, hypoxia and subsequent fibrosis are major immediate contributing factors responsible for the clinical manifestations of CVD. Localized, chronic inflammation is now increasingly being recognized as a key player, directly responsible for stasis dermatitis and hypercoagulable state. The complete ramifications of persistent inflammation in CVD are yet to be understood and serious systemic morbidities such as arterial and cardiac disease are increasingly being recognized in association with CVD.

Dual role for fungal-specific outer kinetochore proteins during cell cycle and development in Magnaporthe oryzae.

The outer kinetochore DASH complex (also known as the Dam1 complex) ensures proper spindle structure and chromosome segregation. While DASH complex protein requirement diverges among different yeasts, its role in filamentous fungi has not yet been investigated. We studied the dynamics and role of middle (Mis12) and outer (Dam1 and Ask1) kinetochore proteins in the filamentous fungal pathogen, Magnaporthe oryzae, which undergoes multiple cell cycle-linked developmental transitions. While Mis12 was constitutively present in the nucleus, Dam1 and Ask1 were recruited only during mitosis. Although Dam1 was not required for viability, loss of its function (dam1Δ) delayed mitotic progression, resulting in impaired conidial and hyphal development. Both Dam1 and Ask1 also localised to the hyphal tips, in the form of punctae oscillating back and forth from the growing ends, suggesting that Magnaporthe DASH complex proteins may play a non-canonical role in polarised growth during interphase, in addition to their function in nuclear segregation during mitosis. Impaired appressorial (infection structure) development and host penetration in the dam1Δ mutant suggest that fungus-specific Dam1 complex proteins could be an attractive target for a novel anti-fungal strategy.This article has an associated First Person interview with the first author of the paper.

A prospective, head-to-head comparison of 2 EUS-guided liver biopsy needles in vivo.

BACKGROUND AND AIMS: Procedural standardization in endoscopic ultrasound-guided liver biopsy (EUS-LB) is necessary to obtain core biopsy specimens for accurate diagnosis. The objective of this study was to directly compare the diagnostic yield of 2 EUS-LB fine-needle biopsy (FNB) systems in vivo. METHODS: In this prospective, single-center study, 108 adult patients undergoing EUS-LB over a 1-year period were included. Each EUS-LB consisted of an EGD, followed by EUS-guided biopsy of the left lobe of the liver sequentially using 2 different 19-gauge needles: the fork-tip (SharkCore) and Franseen (Acquire) FNB systems. Specimens were then reviewed by a GI histopathologist to determine diagnostic adequacy as well as the number of complete portal tracts, specimen length, and degree of fragmentation. RESULTS: In 79.4% of cases, the fork-tip FNB system yielded a final diagnosis compared with 97.2% of the Franseen FNB specimens (P < .001). The mean number of complete portal tracts in the fork-tip FNB samples was 7.07 compared with 9.59 in the Franseen FNB samples (P < .001). The mean specimen length was 13.86 mm for the fork-tip FNB and 15.81 mm for the Franseen FNB (P = .004). Cores were intact in 47.6% of the fork-tip FNB samples and in 75.2% of the Franseen FNB samples (P = .004). CONCLUSIONS: In EUS-LB, we found that the 19-gauge Franseen FNB system resulted in a statistically significant increase in diagnostic adequacy compared with biopsy using the fork-tip FNB system.

Enhanced Solubility and Bioavailability of Dolutegravir by Solid Dispersion Method: In Vitro and In Vivo Evaluation-a Potential Approach for HIV Therapy.

Being a candidate of BCS class II, dolutegravir (DTG), a recently approved antiretroviral drug, possesses solubility issues. The current research was aimed to improve the solubility of the DTG and thereby enhance its efficacy using the solid dispersion technique. In due course, the miscibility study of the drug was performed with different polymers, where Poloxamer 407 (P407) was found suitable to move forward. The solid dispersion of DTG and P407 was formulated using solvent evaporation technique with a 1:1 proportion of drug and polymer, where the solid-state characterization was performed using differential scanning calorimetry, Fourier transform infrared spectroscopy and X-ray diffraction. No physicochemical interaction was found between the DTG and P407 in the fabricated solid dispersion; however, crystalline state of the drug was changed to amorphous as evident from the X-ray diffractogram. A rapid release of DTG was observed from the solid dispersion (>95%), which is highly significant (p<0.05) as compared to pure drug (11.40%), physical mixture (20.07%) and marketed preparation of DTG (35.30%). The drug release from the formulated solid dispersion followed Weibull model kinetics. Finally, the rapid drug release from the solid dispersion formulation revealed increased Cmax (14.56 µg/mL) when compared to the physical mixture (4.12 µg/mL) and pure drug (3.45 µg/mL). This was further reflected by improved bioavailability of DTG (AUC: 105.99±10.07 µg/h/mL) in the experimental Wistar rats when compared to the AUC of animals administered with physical mixture (54.45±6.58 µg/h/mL) and pure drug (49.27±6.16 µg/h/mL). Therefore, it could be concluded that the dissolution profile and simultaneously the bioavailability of DTG could be enhanced by means of the solid dispersion platform using the hydrophilic polymer, P407, which could be projected towards improved efficacy of the drug in HIV/AIDS.

Development and Optimization of Asenapine Sublingual Film Using QbD Approach.

Asenapine, an atypical antipsychotic agent, has been approved for the acute and maintenance treatment of schizophrenia and manic episodes of bipolar disorder. However, the extensive hepatic metabolism limits its oral bioavailability. Therefore, the objective of the current investigation was to develop sublingual film containing asenapine to enhance the therapeutic efficacy. Sublingual films containing asenapine were fabricated using polyethylene oxide and hydroxypropyl methylcellulose by solvent casting method. Design of experiment was used as a statistical tool to optimize the proportion of the film-forming polymers in order to establish the critical quality attributes of the drug formulation. The process was studied in detail by assessing risk of each step as well as parameters and material attributes to reduce the risk to a minimum. A control strategy was defined to ensure manufacture of films according to the target product profile by evaluation of intermediate quality attributes at the end of each process step. Results of optimized formulations showed rapid disintegration, adequate folding endurance, good percentage elongation, tensile strength, and viscosity. Besides, the results from the in vitro dissolution/ex vivo permeation studies showed rapid dissolution (100% in 6 min) and higher asenapine permeation (~ 80% in 90 min) through the sublingual epithelium. In vivo study indicates greater asenapine absorption (31.18 ± 5.01% of administered dose) within 5 min and was comparable with marketed formulation. In summary, the designing plan to develop asenapine formulation was successfully achieved with desired characteristics of the delivery tool for sublingual administration.

One Health approach to cost-effective rabies control in India.

Over 20,000 rabies deaths occur annually in India, representing one-third of global human rabies. The Indian state of Tamil Nadu has pioneered a "One Health" committee to address the challenge of rabies in dogs and humans. Currently, rabies control in Tamil Nadu involves postexposure vaccination of humans after dog bites, whereas potential supplemental approaches include canine vaccination and sterilization. We developed a data-driven rabies transmission model fit to human rabies autopsy data and human rabies surveillance data from Tamil Nadu. Integrating local estimates for canine demography and costs, we predicted the impact of canine vaccination and sterilization on human health outcomes and evaluated cost-effectiveness according to the WHO criteria for India, which correspond to thresholds of $1,582 and $4,746 per disability-adjusted life-years (DALYs) for very cost-effective and cost-effective strategies, respectively. We found that highly feasible strategies focused on stray dogs, vaccinating as few as 7% of dogs annually, could very cost-effectively reduce human rabies deaths by 70% within 5 y, and a modest expansion to vaccinating 13% of stray dogs could cost-effectively reduce human rabies by almost 90%. Through integration over parameter uncertainty, we find that, for a cost-effectiveness threshold above $1,400 per DALY, canine interventions are at least 95% likely to be optimal. If owners are willing to bring dogs to central point campaigns at double the rate that campaign teams can capture strays, expanded annual targets become cost-effective. This case study of cost-effective canine interventions in Tamil Nadu may have applicability to other settings in India and beyond.

A feasibility study of breast cancer genetic risk assessment in a federally qualified health center.

BACKGROUND: The US Preventive Services Task Force (USPSTF) endorses routine screening for genetic risk of breast and/or ovarian cancer as a component of primary health care. Implementation of this recommendation may prove challenging, especially in clinics serving disadvantaged communities. METHODS: The authors tested the feasibility of implementing the USPSTF mandate at a federally qualified health center (FQHC) to identify women who were eligible for genetic counseling (GC). A 12-month usual-care phase was followed by a 12-month intervention phase, during which time cancer genetic risk assessment (CGRA) was systematically performed for all women aged 25 to 69 years who presented for an annual examination. Women who were eligible for GC were recruited to participate in the study. RESULTS: After initiating CGRA, 112 women who were eligible for GC consented to study participation, and 56% of them received a referral for GC from their primary care physician. A subgroup of 50 participants were seen by the same primary care physician during both the usual-care and intervention phases. None of these patients was referred for GC during usual care, compared with 64% after the initiation of CGRA (P < .001). Only 16% of referred participants attended a GC session. CONCLUSIONS: Implementing USPSTF recommendations for CGRA as a standard component of primary health care in FQHCs is feasible and improves referral of minority women for GC, but more work is needed to understand the beliefs and barriers that prevent many underserved women from accessing cancer genetic services.

Psychometric properties of Patient Reported Outcome Measures (PROMs) in patients diagnosed with Acute Respiratory Distress Syndrome (ARDS).

BACKGROUND: The aim of this study was to assess the psychometric properties of the EQ-5D-3 L, the SF-12 v2 and its preference based derivative the SF-6D, and the St Georges Respiratory Questionnaire (SGRQ), in patients diagnosed with Acute Respiratory Distress Syndrome (ARDS). METHODS: Data from the Oscillation in ARDS (OSCAR) randomised unblinded clinical trial of 795 patients diagnosed with ARDS provided the foundation of this secondary psychometric analysis. The three source patient reported outcome measures (PROMs) (EQ-5D-3 L, SF-12 and SGRQ) were collected at both 6 and 12 months post randomisation. All measures were tested for acceptability, reliability, internal consistency, validity and responsiveness. Data from responders at 6 months was used to test for acceptability, reliability, known groups validity and internal responsiveness. Data from patients who responded at both 6 and 12 months was used to test for convergent validity and external responsiveness. RESULTS: Rates of response at both 6 and 12 months post randomisation were 89.88 % for the EQ-5D-3 L, 77.38 % for the SF-6D, 71.43 % for both the physical and mental components of the SF-12 and 38.10 % for the SGRQ. All measures had a Cronbach's Alpha statistic higher than 0.7. For known group's validity, there was no difference in mean summary or utility scores between known groups for all PROMs with minimal effect sizes. All three source measures showed strong convergent and discriminant validity. There was consistent evidence that the SF-6D is an empirically valid and efficient alternative to the EQ-5D-3 L. The EQ-5D-3 L and SGRQ were more responsive compared to the SF-12 and SF-6D with the EQ-5D-3 L generating greater effect sizes than the SGRQ. CONCLUSION: The PROMs explored in this study displayed varying psychometric properties in the context of ARDS. Further research should focus on shortening the SGRQ whilst still maintaining its psychometric properties and mapping between the SGRQ and preference-based measures for future application within economic evaluations of respiratory focused interventions. The selection ofa preferred PROM for evaluative studies within the ARDS context should ultimately depend on the relative importance placed on individual psychometric properties and the importance placed on generation of health utilities for economic evaluation purposes.

Polygenic cis-regulatory adaptation in the evolution of yeast pathogenicity.

The acquisition of new genes, via horizontal transfer or gene duplication/diversification, has been the dominant mechanism thus far implicated in the evolution of microbial pathogenicity. In contrast, the role of many other modes of evolution--such as changes in gene expression regulation-remains unknown. A transition to a pathogenic lifestyle has recently taken place in some lineages of the budding yeast Saccharomyces cerevisiae. Here we identify a module of physically interacting proteins involved in endocytosis that has experienced selective sweeps for multiple cis-regulatory mutations that down-regulate gene expression levels in a pathogenic yeast. To test if these adaptations affect virulence, we created a panel of single-allele knockout strains whose hemizygous state mimics the genes' adaptive down-regulations, and measured their virulence in a mammalian host. Despite having no growth advantage in standard laboratory conditions, nearly all of the strains were more virulent than their wild-type progenitor, suggesting that these adaptations likely played a role in the evolution of pathogenicity. Furthermore, genetic variants at these loci were associated with clinical origin across 88 diverse yeast strains, suggesting the adaptations may have contributed to the virulence of a wide range of clinical isolates. We also detected pleiotropic effects of these adaptations on a wide range of morphological traits, which appear to have been mitigated by compensatory mutations at other loci. These results suggest that cis-regulatory adaptation can occur at the level of physically interacting modules and that one such polygenic adaptation led to increased virulence during the evolution of a pathogenic yeast.

Global Prevalence of Varicella-Associated Complications: A Systematic Review and Meta-Analysis.

INTRODUCTION: Varicella (chickenpox) is an infectious disease caused by the varicella zoster virus affecting children, adolescents, and adults. Varicella symptoms are usually self-limiting; however, different complications with widespread and systemic manifestations can occur. This systematic literature review aims to explore and quantify varicella-associated complication rates. METHODS: Two databases (Embase and MEDLINE), congress abstracts, and reference lists of systematic reviews were screened to identify evidence on varicella complications. Complications were identified and grouped into 14 clinically relevant categories. Proportional meta-analyses were conducted using a random-effects model and tests for heterogeneity and publication bias were performed. Subgroup, sensitivity, and meta-regression analyses were also conducted. A total of 78 studies, spanning 30 countries, were included in the meta-analysis. RESULTS: Pooled prevalence was highest in severe varicella (22.42%; 95% confidence interval [CI] 10.13-37.77), skin-related complications (20.12%; 95% CI 15.48-25.20), and infection-related complications (10.03%; 95% CI 7.47-12.90). Cardiovascular (0.55%; 95% CI 0.08-1.33), genitourinary (1.17%; 95% CI 0.55-1.99), and musculoskeletal (1.54%; 95% CI 1.06-2.11) complications had the lowest pooled prevalence. The remaining complication categories ranged between 1% and 10%. Subgroup analysis showed that complications were more prevalent in children versus adults and in hospitalized patients versus outpatients. Meta-regression analysis found that no ecological level covariates were accurate predictors for the overall prevalence of varicella-associated complications. There was substantial heterogeneity and publication bias across all meta-analyses. CONCLUSION: Results suggest that different types of varicella-associated complications could be frequent, impacting quality of life, and healthcare resource utilisation and budgets. These findings are crucial to raise awareness of the health and economic burden of varicella disease.

A graphical plain language summary is available with this article.

An Individualized Yoga Intervention for People with Functional Neurological Disorder: Case Series.

Functional neurological disorder (FND) is a heterogeneous condition of neurological symptoms that cannot be linked to a specific neurological cause. Yoga combines movement, breathing, and meditation and has established mind-body effects for people who are managing both psychological and neurological conditions. This case series describes key components of a yoga program for people with FND, evaluating feasibility, acceptability, and efficacy via self-report surveys, clinical assessments, and postintervention interview. Four individuals with FND participated in 45-minute, one-to-one virtual yoga sessions, two times a week for 8 weeks. We measured outcomes in four domains (healthcare utilization, FND symptoms, quality of life and self-efficacy, and function and mobility) at baseline, week 4, and week 8. Assessments included the Psychogenic Movement Disorders Rating Scale, timed up-and-go test, Patient Health Questionnaire-15, Brief Illness Perceptions Questionnaire, 36-Item Short Form Health Survey, and University of Washington Self-Efficacy Scale. Four participants completed at least 8 sessions, and two completed the full intervention (16 sessions). There were no adverse events. Two participants reported positive changes after yoga and improved on all clinical assessments (timed up-and-go test and Psychogenic Movement Disorders Rating Scale). Postintervention interview analysis revealed three themes: negative diagnosis experience, perceived health effects of yoga, and session format preferences. This was an exploratory case series describing a yoga intervention that was associated with some benefits for people with FND (decreased FND symptom severity and increased function, perceived health, quality of life, and self-efficacy). A larger case series is warranted to understand how to best select individuals who would benefit from the program.

Identifying Barriers and Facilitators to Accessing Care for Historically Marginalized Communities Affected by Parkinson Disease: A Qualitative Study.

INTRODUCTION: Parkinson disease (PD) is the second most common neurodegenerative disease. Members of the Black Diaspora (MBD) and Hispanic/Latinx people are less likely to receive a timely diagnosis following the onset of symptoms and more likely to experience greater disease severity due to late diagnosis. Historically marginalized populations (i.e., MBD, Hispanic, and Latinx communities) are not accurately represented in research; this, along with many other barriers, compounds underreporting and lack of recognition of PD. It is important to understand barriers to early diagnosis and healthcare access for these historically marginalized populations from the community's perspective. METHODS: Our team conducted two focus groups to identify barriers and facilitators to PD healthcare-seeking behavior. We sought to identify which barriers are modifiable to ultimately improve engagement in neurological care for MBD and Hispanic individuals affected by PD. RESULTS: We enrolled 15 participants (13 female; African/African American/Black n = 10, Hispanic/Puerto Rican n = 3, other n = 2) for two focus groups. Discussions revealed sources of barriers to healthcare-seeking behavior in three main domains: legacy of racism in the United States, ancestral cultural environment, and healthcare system access. These sources influenced individuals' PD knowledge and familiarity. Additionally, participants expressed a desire to know more about PD and called for increased community-based programming for education and awareness. DISCUSSION: This paper uses a community-based participatory research approach to describe the experiences of MBD, Hispanic, and Latinx people in Manhattan and the surrounding areas in relation to possible sources of healthcare disparities and delayed PD diagnosis. These sources have broad implications and should be addressed through collaborative community programming.

Constipation in patients with thiamine deficiency after Roux-en-Y gastric bypass surgery.

BACKGROUND/AIMS: Roux-en-Y gastric bypass surgery is the most common bariatric surgery worldwide. We have described thiamine deficiency in patients with small intestinal bacterial overgrowth after gastric bypass. We hypothesized that symptoms of thiamine deficiency are common after gastric bypass. The aims of this study were to examine the prevalence of and treatment of symptoms of thiamine deficiency after gastric bypass. METHODS: This is a prospective study performed in a large urban, community hospital. Consecutive gastric bypass patients seen from February 1, 2008 to May 1, 2009 are included. Thiamine deficiency in this study included both: consistent clinical symptoms and either (1) low blood thiamine level or (2) resolution of clinical symptoms after receiving thiamine. RESULTS: Of 151 patients, 25 females and 2 males met the criteria for thiamine deficiency (prevalence of 18%). In these 27 patients, 12 had one symptom of thiamine deficiency, while 15 had symptoms consistent with multiple subtypes. Eleven patients reported constipation at 0.33-12 years (mean 4.8) after gastric bypass. Elevated serum folate levels were seen in 6 of 10 tested patients and there was an abnormal glucose-hydrogen breath test in 9 of 10 tested patients, supporting the presence of small intestinal bacterial overgrowth. Frequency of defecation improved after thiamine treatment. CONCLUSION: Thiamine deficiency resulting from small intestinal bacterial overgrowth should be considered in patients being seen for constipation after gastric bypass surgery.