Hardingkatz3484
The cytochrome P450 enzyme CYP-sb21 from the rare actinomycete Sebekia benihana is capable of hydroxylating the immunosuppressive drug molecule cyclosporine A (CsA) primarily at the 4th N-methyl leucine (MeLeu4), giving rise to γ-hydroxy-N-methyl-l-Leu4-CsA (CsA-4-OH). This oxidative modification of CsA leads to dramatically reduced immunosuppressive activity while retaining the hair growth-promoting side-effect, thus demonstrating great application potential in both pharmaceutical and cosmetic industries. However, this P450 enzyme also hydroxylates CsA at the unwanted position of the 9th N-methyl leucine (MeLeu9), indicating that the regioselectivity needs to be improved for the development of CsA-4-OH into a commercial hair growth stimulator. Herein, we report the crystal structure of CYP-sb21 in its substrate-free form at 1.85 Å. Together with sequence and 3D structure comparisons, Autodock-based substrate docking, molecular dynamics (MD) simulation, and site-directed mutagenesis, we identified a number of key residues including R294, E264, and M179 that can improve catalytic efficiency or change the regioselectivity of CYP-sb21 towards CsA, setting the stage for better enzymatic preparation of CsA-4-OH. This study also provides new insights into the substrate recognition and binding mechanism of P450 enzymes that accommodate bulky substrates.
In Bangladesh, the prevention and control strategy of soil-transmitted helminthiasis (STHs) is based on the mass drug administration (MDA) program. Lomeguatrib datasheet Despite bi-annual MDA since 2008, the reported compliance is still below the target, and the STH prevalence is high in several areas. This study was done to assess the feasibility and barriers of integrating health education (HE) intervention to achieve the target MDA compliance in the local context of Bangladesh.
A mixed-method study, utilizing PRISM (Practical Robust Implementation Sustainability Model) framework, was conducted between July 2017 to March 2018 in Dhaka and Sylhet divisions of Bangladesh. A total of 640 school-aged children selected from four different schools were divided into intervention and control groups. Eight focus group discussions (FGDs) and eight in-depth interviews (IDIs) were also conducted among 56 adults, including parents of school-aged children, school teachers, and health officers.
Quantitative findings revealed that HE inteability of integration.
Increased knowledge score and behaviour changes due to HE intervention demonstrated in this study hint that integration of HE with MDA is feasible and can be promising to promote MDA compliance and to reduce STH prevalence in this setting. However, the allocation of adequate budget, as well as coordination and collaboration with local political context, should be addressed for the sustainability of integration.Methanol intoxication can cause irreversible neurologic sequelae if unrecognized and untreated. Ingestion is the most common form of toxicity; however, dermal and inhalational exposures likewise occur but are documented rarely. While acute intoxication is commonly encountered, chronic exposure to methanol should also be highlighted. We report a case of a 57-year old female presenting in the emergency room with progressive dyspnea, metabolic acidosis with high anion gap, and metabolic encephalopathy. After emergency hemodialysis, the patient complained of vision loss on both eyes. Initial non-contrast cranial magnetic resonance imaging (MRI) revealed restricted diffusion of the intraorbital segment of both optic nerves. A thorough history revealed that she was applying a clear colorless liquid bought online all over her body for alleged pruritus for more than a year. The syndrome of metabolic acidosis with high anion gap, metabolic encephalopathy, vision loss, and laboratory findings led us to suspect a diagnosis of chronic methanol poisoning with an acute component. The liquid in question was sent for chemical analysis and result showed that it consisted of 95.5% Methanol. This case highlights the need for high index of clinical suspicion for methanol toxicity in the absence of oral consumption, the complications of chronic form of methanol intoxication, and the uncommon radiologic finding seen in diffusion-weighted imaging (DWI).
Parkinson's disease (PD) treatment should follow guidelines and be tailored to each patient. Large database analyses can provide insights into prescribing patterns.
Retrospective, cross-sectional study of patients (≥30years) with PD diagnosis (ICD-10; schizophrenia/cerebrovascular disease excluded) using health insurance claims data (April 2008-December 2016) from the Japan Medical Data Vision database. Prescription patterns of anti-PD drugs were analysed by patient age and sex, calendar year, and overall.
The analysis comprised 155,493 PD patient-years (56.1% women, mean 73.4years). Patient number increased each year, mainly because of database expansion. L-dopa as monotherapy was the most common prescription (22.7% of patient-years); non-ergot dopamine agonists (DAs) were also common (7.6% as monotherapy, 6.8% with L-dopa). Monotherapy was prescribed for ~50% of patient-years, two drugs for 14.1%, and at least three drugs for 18.4%. Consistent with Japanese guidelines, L-dopa was mostly prescribed to older patients (≥60years), whereas non-ergot DAs were mostly prescribed to middle-aged patients (peak at 50-69years). Between 2008 and 2011, L-dopa prescription decreased while that of non-ergot DAs increased; this pattern reversed between 2012 and 2016.
These results indicate that Japanese clinicians are adhering to Japanese guidelines and tailoring anti-PD treatment to individual patients.
These results indicate that Japanese clinicians are adhering to Japanese guidelines and tailoring anti-PD treatment to individual patients.Plastics are ubiquitous in the aquatic environment and their degradation of fragments down to the nanoscale level have raised concerns given their ability to pervade cells. The accumulation of nanoparticles could lead to molecular crowding which can alter the normal functioning of enzymes. The purpose of this study was to examine the influence of polystyrene nanoparticles (NPs) on the fractal kinetics of the lactate dehydrogenase reaction pyruvate + NADH ↔ lactate + NAD+. The influence of NPs on LDH activity was examined first in vitro to highlight specific effects and secondly in mussels exposed to NPs in vivo for 24h at 15 °C. The reaction rates of LDH were determined with increasing concentrations of pyruvate to reach saturation at circa 1 mM pyruvate. The addition of F-actin, a known binding template for LDH, revealed a characteristic change in reaction rates associated with fractal organization. The addition of 50 and 100 nm transparent NPs also produced these changes. The fractal dimension was determined and revealed that both F-actin and NPs reduced the fractal dimension of the LDH reaction. The addition of viscosity sensor probe in the reaction media revealed viscosity waves during the reaction at low substrate concentrations thought to be associated to synchronized switching between the relaxed and tensed states of LDH. The amplitude and the frequency of viscosity waves were increased by both NPs and F-actin which were associated with increased reaction rates. In mussels exposed to NPs, the isolation of digestive gland subcellular fraction revealed that LDH activity was significantly influenced by the fractal dimension of the LDH reaction where a loss of affinity (high fractal KM) was detected in mussels exposed to the high concentrations of NPs. It is concluded that polystyrene NPs could change the biophysical properties of the cytoplasm such as the fractal organization of the intracellular environment during the LDH reaction.Gastrointestinal toxicity is frequently observed secondary to accidental or therapeutic radiation exposure. However, the variation in the intestinal metabolites after abdominal radiation exposure remains ambiguous. In the present study, C57BL/6 mice were exposed to 0, 2, and 20 Gy irradiation dose. The Head and chest of each mouse were covered with a lead shield before x-ray irradiation. 24 h post-irradiation treatment, intestinal tissue of each mouse was excised and prepared for metabolites measurement using gas chromatography-mass spectrometry (GC-MS). Our comprehensive analysis of metabolites in the intestinal tissues detected 44 metabolites after irradiation, including amino acids, carbohydrates, organic acids, and sugars. Amino acid levels in the intestinal tissue gradually rose, dependent on the radiation dose, perhaps as an indication of oxidative stress. Our findings raise the possibility that amino acid metabolism may be a potential target for the development of treatments to alleviate or mitigate the harmful effects of oxidative stress-related gastrointestinal toxicity due to radiation exposure.
Multidrug-resistant tuberculosis (MDR-TB) is an increasing problem worldwide, and 24% occurs in India. Linezolid is associated with improved MDR-TB treatment outcomes but causes significant side-effects and drug susceptibility testing (DST) is rarely available. This study assessed whether clinical factors could predict linezolid resistance.
An observational cohort of adults and adolescents with MDR-TB at a tertiary care hospital in Mumbai, India was analyzed for clinical, laboratory, and radiographic findings associated with linezolid resistance.
In total, 343 MDR-TB patients had linezolid DST performed, and 23 (6.7%) had linezolid-resistant MDR-TB. Univariable analysis associated linezolid resistance with underweight (odds ratio (OR)-1.07, 95% confidence interval (CI)1.01-1.12); number of previous providers (OR1.03, 95% CI1.00-1.05); previous treatment with linezolid (OR1.12, 95% CI1.06-1.05), bedaquiline (OR1.55, 95% CI1.22-1.98), or clofazimine (OR1.08 95% CI1.03-1.16); cavitary disease (OR1.10, 95% CI1.04-1.16) and percent lung involvement (OR1.02, 95% CI1.01-1.03) on radiograph. DST associated linezolid resistance with resistance to fluoroquinolones (OR1.08, 95% CI1.01-1.14), injectables (OR1.09, 95% CI1.03-1.15), ethionamide (OR1.09, 95% CI1.03-1.15), and PAS (OR1.13, 95% CI1.06-1.21). In multivariate analysis, only prior linezolid and percent lung involvement were associated with linezolid resistance.
To maximize treatment benefits while minimizing toxicity, DST remains an important tool to identify linezolid resistance.
To maximize treatment benefits while minimizing toxicity, DST remains an important tool to identify linezolid resistance.Proteins with intrinsic or unfolded state disorder comprise a new frontier in structural biology, requiring the characterization of diverse and dynamic structural ensembles. We introduce a comprehensive Bayesian framework, the Extended Experimental Inferential Structure Determination (X-EISD) method, that calculates the maximum log-likelihood of a disordered protein ensemble. X-EISD accounts for the uncertainties of a range of experimental data and back-calculation models from structures, including NMR chemical shifts, J-couplings, Nuclear Overhauser Effects (NOEs), paramagnetic relaxation enhancements (PREs), residual dipolar couplings (RDCs), hydrodynamic radii (R h ), single molecule fluorescence Förster resonance energy transfer (smFRET) and small angle X-ray scattering (SAXS). We apply X-EISD to the joint optimization against experimental data for the unfolded drkN SH3 domain and find that combining a local data type, such as chemical shifts or J-couplings, paired with long-ranged restraints such as NOEs, PREs or smFRET, yields structural ensembles in good agreement with all other data types if combined with representative IDP conformers.