Examining the Intrapersonal, Interpersonal and Community Level Correlates of Access to Medical Care Among Women Employed by Sex Work in Southern Uganda: A cross-sectional Analysis of the Kyaterekera Study.

Women employed by sex work (WESW) experience significant gaps in accessing necessary healthcare services, leading to unmet health needs. Yet, there is a dearth of literature on the barriers to medical care access among WESW in Uganda. We used data from the Kyaterekera baseline to examine the correlates of access to medical care among WESW, defined as the ability of individuals to obtain the necessary healthcare services they require in a timely, affordable, and equitable manner. The Kyaterekera study recruited 542 WESW aged 18-58 years from Southern Uganda. We conducted a multilevel linear regression model to determine the intrapersonal (age, education level, marital status, HIV knowledge, and asset ownership), interpersonal (family cohesion and domestic violence attitudes), and community (community satisfaction, sex work stigma and distance to health facility) level correlates of access to medical care among WESW. Intrapersonal and interpersonal factors were associated with access to medical care among WESW. There was no significant association between community level factors and access to medical care. WESW with secondary education (ß = 0.928, 95% CI = 0.007, 1.849) were associated with increased access to medical care. WESW with high asset ownership (ß = -1.154, 95% CI= -1.903, -0.405), high family cohesion (ß = -0.069, 95% CI= -0.106, -0.031), and high domestic violence attitudes (ß = -0.253, 95% CI= -0.438, -0.068) were associated with decreased access to medical care. The findings emphasize the critical need for targeted family strengthening interventions to enhance family support for WESW and address domestic violence.

Demonstrating the Feasibility of an Economic Empowerment and Health Promotion Intervention among Low-Income Women Affected by HIV in New York City.

Women of color in the U.S. face systematic exclusion from the labor market, work protections, and employer-based benefits. Women's economic vulnerability increases their susceptibility to health-related issues, including HIV transmission and substance use, which are work-restricting disabilities, by constraining their capacity to effectively reduce risk. The Women's Economic Empowerment pilot examined the feasibility of a structural intervention, implemented at a neighborhood agency, combining both health promotion and economic empowerment components as a pathway to accessing an urban job market for low-income women with work-restricting disabilities, including living with HIV. Ten women clients from a partner agency in New York completed four health promotion sessions, six financial literacy sessions, and a concurrent opportunity to match savings; some also followed with up to 24 vocational rehabilitation sessions. Interviews captured self-reported data on health promotion and financial outcomes at pre-/post-intervention and 3-month follow-up. Qualitative analysis of recorded group sessions and field notes demonstrate that women express improved HVI/STI knowledge and problem-solving strategies for risk reduction, a shared optimism for the future due to group participation, enhanced social support through relationship-building, a heightened sense of empowerment regarding financial decision making, and a desire to re-engage in the labor force. Findings suggest an empowering approach to re-engage women impacted by poverty, unemployment, and disabilities, including living with HIV, into the workforce may be implemented in a community setting.

Economic Abuse and Care-seeking Practices for HIV and Financial Support Services in Women Employed by Sex Work: A Cross-Sectional Baseline Assessment of a Clinical Trial Cohort in Uganda.

Economic hardship is a driver of entry into sex work, which is associated with high HIV risk. Yet, little is known about economic abuse in women employed by sex work (WESW) and its relationship to uptake of HIV prevention and financial support services. This study used cross-sectional baseline data from a multisite, longitudinal clinical trial that tests the efficacy of adding economic empowerment to traditional HIV risk reduction education on HIV incidence in 542 WESW. Mixed effects logistic and linear regressions were used to examine associations in reported economic abuse by demographic characteristics, sexual behaviors, HIV care-seeking, and financial care-seeking. Mean age was 31.4 years. Most WESW were unmarried (74%) and had less than primary school education (64%). 48% had savings, and 72% had debt. 93% reported at least one economic abuse incident. Common incidents included being forced to ask for money (80%), having financial information kept from them (61%), and being forced to disclose how money was spent (56%). WESW also reported partners/relatives spending money needed for bills (45%), not paying bills (38%), threatening them to quit their job(s) (38%), and using physical violence when earning income (24%). Married/partnered WESW (OR = 2.68, 95% CI:1.60-4.48), those with debt (OR = 1.70, 95% CI:1.04-2.77), and those with sex-work bosses (OR = 1.90, 95% CI:1.07-3.38) had higher economic abuse. Condomless sex (ß = +4.43, p < .05) was higher among WESW experiencing economic abuse, who also had lower odds of initiating PrEP (OR = .39, 95% CI:.17-.89). WESW experiencing economic abuse were also more likely to ask for cash among relatives (OR = 2.36, 95% CI:1.13-4.94) or banks (OR = 2.12, 95% CI:1.11-4.03). The high prevalence of HIV and economic abuse in WESW underscores the importance of integrating financial empowerment in HIV risk reduction interventions for WESW, including education about economic abuse and strategies to address it. Programs focusing on violence against women should also consider economic barriers to accessing HIV prevention services.

Using the multiphase optimization strategy (MOST) framework to optimize an intervention to increase COVID-19 testing for Black and Latino/Hispanic frontline essential workers: A study protocol.

BACKGROUND: Among those at highest risk for COVID-19 exposure is the large population of frontline essential workers in occupations such food service, retail, personal care, and in-home health services, among whom Black and Latino/Hispanic persons are over-represented. For those not vaccinated and at risk for exposure to COVID-19, including frontline essential workers, regular (approximately weekly) COVID-19 testing is recommended. However, Black and Latino/Hispanic frontline essential workers in these occupations experience serious impediments to COVID-19 testing at individual/attitudinal- (e.g., lack of knowledge of guidelines), social- (e.g., social norms), and structural-levels of influence (e.g., poor access), and rates of testing for COVID-19 are insufficient. METHODS/DESIGN: The proposed community-engaged study uses the multiphase optimization strategy (MOST) framework and an efficient factorial design to test four candidate behavioral intervention components informed by an integrated conceptual model that combines critical race theory, harm reduction, and self-determination theory. They are A) motivational interview counseling, B) text messaging grounded in behavioral economics, C) peer education, and D) access to testing (via navigation to an appointment vs. a self-test kit). All participants receive health education on COVID-19. The specific aims are to: identify which components contribute meaningfully to improvement in the primary outcome, COVID-19 testing confirmed with documentary evidence, with the most effective combination of components comprising an "optimized" intervention that strategically balances effectiveness against affordability, scalability, and efficiency (Aim 1); identify mediators and moderators of the effects of components (Aim 2); and use a mixed-methods approach to explore relationships among COVID-19 testing and vaccination (Aim 3). Participants will be N = 448 Black and Latino/Hispanic frontline essential workers not tested for COVID-19 in the past six months and not fully vaccinated for COVID-19, randomly assigned to one of 16 intervention conditions, and assessed at 6- and 12-weeks post-baseline. Last, N = 50 participants will engage in qualitative in-depth interviews. DISCUSSION: This optimization trial is designed to yield an effective, affordable, and efficient behavioral intervention that can be rapidly scaled in community settings. Further, it will advance the literature on intervention approaches for social inequities such as those evident in the COVID-19 pandemic. TRIAL REGISTRATION: ClinicalTrials.gov: NCT05139927 ; Registered on 11/29/2021. Protocol version 1.0. May 2, 2022, Version 1.0.

Structural Insights into Novel 15-Prostaglandin Dehydrogenase Inhibitors.

We discovered SW033291 in a high throughput chemical screen aimed at identifying 15-prostaglandin dehydrogenase (15-PGDH) modulators. The compound exhibited inhibitory activity in in vitro biochemical and cell-based assays of 15-PGDH activity. We subsequently demonstrated that this compound, and several analogs thereof, are effective in in vivo mouse models of bone marrow transplant, colitis, and liver regeneration, where increased levels of PGE2 positively potentiate tissue regeneration. To better understand the binding of SW033291, we carried out docking studies for both the substrate, PGE2, and an inhibitor, SW033291, to 15-PGDH. Our models suggest similarities in the ways that PGE2 and SW033291 interact with key residues in the 15-PGDH-NAD+ complex. We carried out molecular dynamics simulations (MD) of SW033291 bound to this complex, in order to understand the dynamics of the binding interactions for this compound. The butyl side chain (including the sulfoxide) of SW033291 participates in crucial binding interactions that are similar to those observed for the C15-OH and the C16-C20 alkyl chain of PGE2. In addition, interactions with residues Ser138, Tyr151, and Gln148 play key roles in orienting and stabilizing SW033291 in the binding site and lead to enantioselectivity for the R-enantiomer. Finally, we compare the binding mode of (R)-S(O)-SW033291 with the binding interactions of published 15-PGDH inhibitors.

Simultaneous Control of Endogenous and User-Defined Genetic Pathways Using Unique ecDHFR Pharmacological Chaperones.

Destabilizing domains (DDs), such as a mutated form of Escherichia coli dihydrofolate reductase (ecDHFR), confer instability and promote protein degradation. However, when combined with small-molecule stabilizers (e.g., the antibiotic trimethoprim), DDs allow positive regulation of fusion protein abundance. Using a combinatorial screening approach, we identified and validated 17 unique 2,4-diaminopyrimidine/triazine-based ecDHFR DD stabilizers, at least 15 of which were ineffective antibiotics against E. coli and S. aureus. Identified stabilizers functioned in vivo to control an ecDHFR DD-firefly luciferase in the mouse eye and/or the liver. Next, stabilizers were leveraged to perform synergistic dual functions in vitro (HeLa cell death sensitization) and in vivo (repression of ocular inflammation) by stabilizing a user-defined ecDHFR DD while also controlling endogenous signaling pathways. Thus, these newly identified pharmacological chaperones allow for simultaneous control of compound-specific endogenous and user-defined genetic pathways, the combination of which may provide synergistic effects in complex biological scenarios.

HORMAD1 Is a Negative Prognostic Indicator in Lung Adenocarcinoma and Specifies Resistance to Oxidative and Genotoxic Stress.

Cancer testis antigens (CTA) are expressed in testis and placenta and anomalously activated in a variety of tumors. The mechanistic contribution of CTAs to neoplastic phenotypes remains largely unknown. Using a chemigenomics approach, we find that the CTA HORMAD1 correlates with resistance to the mitochondrial complex I inhibitor piericidin A in non-small cell lung cancer (NSCLC). Resistance was due to a reductive intracellular environment that attenuated the accumulation of free radicals. In human lung adenocarcinoma (LUAD) tumors, patients expressing high HORMAD1 exhibited elevated mutational burden and reduced survival. HORMAD1 tumors were enriched for genes essential for homologous recombination (HR), and HORMAD1 promoted RAD51-filament formation, but not DNA resection, during HR. Accordingly, HORMAD1 loss enhanced sensitivity to γ-irradiation and PARP inhibition, and HORMAD1 depletion significantly reduced tumor growth in vivo These results suggest that HORMAD1 expression specifies a novel subtype of LUAD, which has adapted to mitigate DNA damage. In this setting, HORMAD1 could represent a direct target for intervention to enhance sensitivity to DNA-damaging agents or as an immunotherapeutic target in patients.Significance: This study uses a chemigenomics approach to demonstrate that anomalous expression of the CTA HORMAD1 specifies resistance to oxidative stress and promotes HR to support tumor cell survival in NSCLC. Cancer Res; 78(21); 6196-208. ©2018 AACR.

Recruiting and retaining service agencies and public health providers in longitudinal studies: Implications for community-engaged implementation research.

This article addresses a lack of attention in the implementation science literature regarding how to overcome recruitment and retention challenges in longitudinal studies involving large samples of service agencies and health service providers ("providers"). Herein, we provide a case-illustration of procedures that improved recruitment and retention in a longitudinal, mixed-method study-Project Interprofessional Collaboration Implementation-funded by the US National Institute of Mental Health. Project Interprofessional Collaboration Implementation included counselors, program workers, educators, and supervisors. We present a research-engagement model to overcome barriers that included developing a low-burden study, social gatherings to engage stakeholders, protocols to recruit agencies and providers, comprehensive record-keeping, research procedures as incentives to participation, a plan to retain hard-to-reach participants, and strategies for modifying incentives over time. Using our model, we retained 36 agencies over the life of the project. Between baseline (N = 379) and 12-month follow-up (N = 285), we retained 75% of the sample and between the 12- (N = 285) and 24-month follow-ups (N = 256), we retained 90%. For qualitative interviews (between baseline and 12-month follow-up and between 12- and 24-month follow-ups), we retained 100% of the sample (N = 20). We provide a summary of frequency of contacts required to initiate data collection and time required for data collection. The model responded to environmental changes in policy and priorities that would not have been achievable without the expertise of community partners. To recruit and retain large samples longitudinally, researchers must strategically engage community partners. The strategies imbedded in our model can be performed with moderate levels of effort and human resources. Creating opportunities for research partners to participate in all phases of the research cycle is recommended, which can help build research capacity for future research.

Discovery of Cytochrome P450 4F11 Activated Inhibitors of Stearoyl Coenzyme A Desaturase.

Stearoyl-CoA desaturase (SCD) catalyzes the first step in the conversion of saturated fatty acids to unsaturated fatty acids. Unsaturated fatty acids are required for membrane integrity and for cell proliferation. For these reasons, inhibitors of SCD represent potential treatments for cancer. However, systemically active SCD inhibitors result in skin toxicity, which presents an obstacle to their development. We recently described a series of oxalic acid diamides that are converted into active SCD inhibitors within a subset of cancers by CYP4F11-mediated metabolism. Herein, we describe the optimization of the oxalic acid diamides and related N-acyl ureas and an analysis of the structure-activity relationships related to metabolic activation and SCD inhibition.

Chemistry-First Approach for Nomination of Personalized Treatment in Lung Cancer.

Diversity in the genetic lesions that cause cancer is extreme. In consequence, a pressing challenge is the development of drugs that target patient-specific disease mechanisms. To address this challenge, we employed a chemistry-first discovery paradigm for de novo identification of druggable targets linked to robust patient selection hypotheses. In particular, a 200,000 compound diversity-oriented chemical library was profiled across a heavily annotated test-bed of >100 cellular models representative of the diverse and characteristic somatic lesions for lung cancer. This approach led to the delineation of 171 chemical-genetic associations, shedding light on the targetability of mechanistic vulnerabilities corresponding to a range of oncogenotypes present in patient populations lacking effective therapy. Chemically addressable addictions to ciliogenesis in TTC21B mutants and GLUT8-dependent serine biosynthesis in KRAS/KEAP1 double mutants are prominent examples. These observations indicate a wealth of actionable opportunities within the complex molecular etiology of cancer.

Policy Interventions Shaping HIV Prevention: Providers' Active Role in the HIV Continuum of Care.

The U.S. Centers for Disease Control and Prevention (CDC) Diffusion of Effective Behavioral Interventions project has disseminated HIV behavioral interventions (EBIs) across the United States since the 1990s. In 2011, the CDC launched the High-Impact HIV Prevention (HIP) project, providing EBIs plus high-impact services (HIV testing, primary care, and support services). Providers (nurses, social workers, educators) are unable to consistently make linkages; thus, numerous at-risk individuals are not benefitting from HIP. Research on providers' roles in the HIV Continuum of Care-linking clients to HIV testing, primary care, and support services-is lacking. This article helps fill this gap with evidence that providers exposed to EBIs, whose agencies offer EBIs, more frequently link clients to high-impact services. This is based on diffusion of innovations theory, where individuals in social networks influence one another's adoption of innovations. We hypothesize that providers are exposed to EBIs via training, reading and hearing about EBIs, and/or discussing EBIs with colleagues. We used cross-sectional data from 379 providers from 36 agencies in New York City. We used multilevel ordinal logistic regression models to test associations between provider exposure to EBIs (agency provides EBIs) and frequency of linkages to high-impact services. Providers exposed to greater numbers of EBIs more frequently link clients to HIV, hepatitis C (HEP-C), and sexually transmitted infections testing; to primary care; and to drug treatment and mental health services. Providers link clients most frequently to primary care and HIV testing and least frequently to HEP-C testing and syringe exchange. Findings suggest a dose effect, with exposure to more EBIs resulting in more linkages. Findings show a staged, evidence-based prevention approach that includes exposure to EBIs, leading to providers linking clients to high-impact services. There needs to be emphasis on inspiring providers to engage with high-impact services at the elevated levels needed to end the epidemic.

Factors That Influence Linkages to HIV Continuum of Care Services: Implications for Multi-Level Interventions.

Worldwide, the human immunodeficiency virus (HIV) continuum of care involves health promotion providers (e.g., social workers and health educators) linking patients to medical personnel who provide HIV testing, primary care, and antiretroviral treatments. Regrettably, these life-saving linkages are not always made consistently and many patients are not retained in care. To design, test and implement effective interventions, we need to first identify key factors that may improve linkage-making. To help close this gap, we used in-depth interviews with 20 providers selected from a sample of 250 participants in a mixed-method longitudinal study conducted in New York City (2012-2017) in order to examine the implementation of HIV services for at-risk populations. Following a sociomedical framework, we identified provider-, interpersonal- and environmental-level factors that influence how providers engage patients in the care continuum by linking them to HIV testing, HIV care, and other support services. These factors occurred in four domains of reference: Providers' Professional Knowledge Base; Providers' Interprofessional Collaboration; Providers' Work-Related Changes; and Best Practices in a Competitive Environment. Of particular importance, our findings show that a competitive environment and a fear of losing patients to other agencies may inhibit providers from engaging in linkage-making. Our results suggest relationships between factors within and across all four domains; we recommend interventions to modify factors in all domains for maximum effect toward improving care continuum linkage-making. Our findings may be applicable in different areas of the globe with high HIV prevalence.

Are Predictive Equations for Estimating Resting Energy Expenditure Accurate in Asian Indian Male Weightlifters?

BACKGROUND: The accuracy of existing predictive equations to determine the resting energy expenditure (REE) of professional weightlifters remains scarcely studied. Our study aimed at assessing the REE of male Asian Indian weightlifters with indirect calorimetry and to compare the measured REE (mREE) with published equations. A new equation using potential anthropometric variables to predict REE was also evaluated. MATERIALS AND METHODS: REE was measured on 30 male professional weightlifters aged between 17 and 28 years using indirect calorimetry and compared with the eight formulas predicted by Harris-Benedicts, Mifflin-St. Jeor, FAO/WHO/UNU, ICMR, Cunninghams, Owen, Katch-McArdle, and Nelson. Pearson correlation coefficient, intraclass correlation coefficient, and multiple linear regression analysis were carried out to study the agreement between the different methods, association with anthropometric variables, and to formulate a new prediction equation for this population. RESULTS: Pearson correlation coefficients between mREE and the anthropometric variables showed positive significance with suprailiac skinfold thickness, lean body mass (LBM), waist circumference, hip circumference, bone mineral mass, and body mass. All eight predictive equations underestimated the REE of the weightlifters when compared with the mREE. The highest mean difference was 636 kcal/day (Owen, 1986) and the lowest difference was 375 kcal/day (Cunninghams, 1980). Multiple linear regression done stepwise showed that LBM was the only significant determinant of REE in this group of sportspersons. A new equation using LBM as the independent variable for calculating REE was computed. REE for weightlifters = -164.065 + 0.039 (LBM) (confidence interval -1122.984, 794.854]. This new equation reduced the mean difference with mREE by 2.36 + 369.15 kcal/day (standard error = 67.40). CONCLUSION: The significant finding of this study was that all the prediction equations underestimated the REE. The LBM was the sole determinant of REE in this population. In the absence of indirect calorimetry, the REE equation developed by us using LBM is a better predictor for calculating REE of professional male weightlifters of this region.

Novel Molecular Interactions of Acylcarnitines and Fatty Acids with Myoglobin.

Previous research has indicated that long-chain fatty acids can bind myoglobin (Mb) in an oxygen-dependent manner. This suggests that oxy-Mb may play an important role in fuel delivery in Mb-rich muscle fibers (e.g. type I fibers and cardiomyocytes), and raises the possibility that Mb also serves as an acylcarnitine-binding protein. We report for the first time the putative interaction and affinity characteristics for different chain lengths of both fatty acids and acylcarnitines with oxy-Mb using molecular dynamic simulations and isothermal titration calorimetry experiments. We found that short- to medium-chain fatty acids or acylcarnitines (ranging from C2:0 to C10:0) fail to achieve a stable conformation with oxy-Mb. Furthermore, our results indicate that C12:0 is the minimum chain length essential for stable binding of either fatty acids or acylcarnitines with oxy-Mb. Importantly, the empirical lipid binding studies were consistent with structural modeling. These results reveal that: (i) the lipid binding affinity for oxy-Mb increases as the chain length increases (i.e. C12:0 to C18:1), (ii) the binding affinities of acylcarnitines are higher when compared with their respective fatty acid counterparts, and (iii) both fatty acids and acylcarnitines bind to oxy-Mb in 1:1 stoichiometry. Taken together, our results support a model in which oxy-Mb is a novel regulator of long-chain acylcarnitine and fatty acid pools in Mb-rich tissues. This has important implications for physiological fuel management during exercise, and relevance to pathophysiological conditions (e.g. fatty acid oxidation disorders and cardiac ischemia) where long-chain acylcarnitine accumulation is evident.

Design and synthesis of cis-restricted benzimidazole and benzothiazole mimics of combretastatin A-4 as antimitotic agents with apoptosis inducing ability.

A series of colchicine site binding tubulin inhibitors were designed and synthesized by the modification of the combretastatin A-4 (CA4) pharmacophore. The ring B was replaced by the pharmacologically relevant benzimidazole or benzothiazole scaffolds, and the cis-configuration of the olefinic bond was restricted by the incorporation of a pyridine ring which is envisaged by the structural resemblance to a tubulin inhibitor like E7010. These compounds were evaluated for their antiproliferative activity on selected cancer cell lines and an insight in the structure activity relationship was developed. The most potent compounds (6c and 6l) demonstrated an antiproliferative effect comparable and superior to that of CA4 (GI50 up to 40nM). Mitotic cell cycle arrest in G2/M phase revealed the disruption of microtubule dynamics that was confirmed by tubulin polymerization assays and immunocytochemistry studies at the cellular level. The molecular docking studies suggested that the binding of these mimics at the colchicine site of the tubulin is similar to that of combretastatin A-4.

Recent advances in computer-aided drug design as applied to anti-influenza drug discovery.

Influenza is a seasonal and serious health threat, and the recent outbreak of H7N9 following the pandemic spread of H1N1 in 2009 has served to emphasize the importance of anti-influenza drug discovery. Zanamivir (Relenza™) and oseltamivir (Tamiflu(®)) are two antiviral drugs currently recommended by the CDC for treating influenza. Both are examples of the successful application of structure-based drug design strategies. These strategies have combined computer- based approaches, such as docking- and pharmacophore-based virtual screening with X-ray crystallographic structural analyses. Docking is a routinely used computational method to identify potential hits from large compound libraries. This method has evolved from simple rigid docking approaches to flexible docking methods to handle receptor flexibility and to enhance hit rates in virtual screening. Virtual screening approaches can employ both ligand-based and structurebased pharmacophore models depending on the available information. The exponential growth in computing power has increasingly facilitated the application of computer-aided methods in drug discovery, and they now play significant roles in the search for novel therapeutics. An overview of these computational tools is presented in this review, and recent advances and challenges will be discussed. The focus of the review will be anti-influenza drug discovery and how advances in our understanding of viral biology have led to the discovery of novel influenza protein targets. Also discussed will be strategies to circumvent the problem of resistance emerging from rapid mutations that has seriously compromised the efficacy of current anti-influenza therapies.

Interactions of acetylcholine binding site residues contributing to nicotinic acetylcholine receptor gating: role of residues Y93, Y190, K145 and D200.

The nicotinic acetylcholine receptor exhibits multiple conformational states, resting (channel closed), active (channel open) and desensitized (channel closed). The resting state may be distinguished from the active and desensitized states by the orientation of loop C in the extracellular ligand binding domain (LBD). Homology modeling was used to generate structures of the Torpedo californica α2ßδγ nAChR that initially represent the resting state (loop C open) and the desensitized state (loop C closed). Molecular dynamics (MD) simulations were performed on the extracellular LBD on each nAChR conformational state, with and without the agonist anabaseine present in each binding site (the αγ and the αδ sites). Three MD simulations of 10ns each were performed for each of the four conditions. Comparison of dynamics revealed that in the presence of agonist, loop C was drawn inward and attains a more stable conformation. Examination of side-chain interactions revealed that residue αY190 exhibited hydrogen-bonding interactions either with residue αY93 in the ligand binding site or with residue αK145 proximal to the binding site. αK145 also exhibited side chain (salt bridge) interactions with αD200 and main chain interactions with αY93. Residues αW149, αY198, γY116/δT119, γL118/δL121 and γL108/δL111 appear to play the role of stabilizing ligand in the binding site. In MD simulations for the desensitized state, the effect of ligand upon the interactions among αK145, αY190, and αY93 as well as ligand-hydrogen-bonding to αW149 were more pronounced at the αγ interface than at the αδ interface. Differences in affinity for the desensitized state were determined experimentally to be 10-fold. The changes in side chain interactions observed for the two conformations and induced by ligand support a model wherein hydrogen bond interactions between αD200 and αY93 are broken and rearrange to form a salt-bridge between αK145 and αD200 and hydrogen bond interactions between αY93 and αY190 and between αK145 and αY190.

Pharmacophore-based virtual screening to aid in the identification of unknown protein function.

A pharmacophore-based virtual screening method was developed and validated for use in predicting the function of a novel protein in terms of small metabolite binding. Five test cases were used for the validation study which spanned two different folds, four superfamilies, and three enzyme classes. Binding sites were predicted using a combination of two methods (CASTp and THEMATICS). The binding site was mapped with chemical probes representing hydrogen-bond donor, acceptor, negative ionizable, positive ionizable, and hydrophobe. The interaction maps were converted to three or four feature pharmacophore models and used to search a database containing 80 018 tautomers/protomers/conformers of 10 535 metabolites. The pharmacophore-based virtual screening eliminated >92% of the database as potential substrates and retrieved specific hits, which were ranked using a physics-based scoring function. The known substrate or product was ranked within the top 0.7% and substrate-like compounds within the top 1% of the metabolite database for all of the five test cases. The results suggest that using this pharmacophore-based virtual screening is a time-efficient strategy that can be applied to screen large databases to help predict the function of small metabolite binding proteins.

Therapeutic effects of tender coconut water on oxidative stress in fructose fed insulin resistant hypertensive rats.

OBJECTIVE: To investigate whether tender coconut water (TCW) mitigates oxidative stress in fructose fed hypertensive rats. METHODS: Male Sprague Dawley rats were fed with fructose rich diet and treated with TCW (4 mL/100 g of body weight) for 3 subsequent weeks. Systolic blood pressure was measured every three days using the indirect tail cuff method. At the end of the experimental period, plasma glucose and insulin, serum triglycerides and free fatty acids, lipid peroxidation markers (MDA, hydroperoxides and conjugated dienes) and the activities of antioxidant enzymes were analyzed in all the groups. RESULTS: Treatment with TCW significantly lowered the systolic blood pressure and reduced serum triglycerides and free fatty acids. Plasma glucose and insulin levels and lipid peroxidation markers such as MDA, hydroperoxides and conjugated dienes were significantly reduced in fructose fed rats treated with TCW. Activities of antioxidant enzymes are up regulated significantly in TCW treated rats. Histopathological analysis of liver showed that TCW treatment reduced the lipid accumulation and inflammatory infiltration without any significant hepatocellular damage. CONCLUSIONS: The overall results suggest that, TCW treatment could prevent and reverse high blood pressure induced by high fructose diet probably by inhibition of lipid peroxidation, upregulation of antioxidant status and improved insulin sensitivity.