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81.
MHAA4549A is a human immunoglobulin G1 (IgG1) monoclonal antibody that binds to a highly conserved epitope on the stalk of influenza A hemagglutinin and blocks the hemagglutinin-mediated membrane fusion in the endosome, neutralizing all known human influenza A strains. Pharmacokinetics (PK) of MHAA4549A and its related antibodies were determined in DBA/2J and Balb-c mice at 5 mg/kg and in cynomolgus monkeys at 5 and 100 mg/kg as a single intravenous dose. Serum samples were analyzed for antibody concentrations using an ELISA and the PK was evaluated using WinNonlin software. Human PK profiles were projected based on the PK in monkeys using species-invariant time method. The human efficacious dose projection was based on in vivo nonclinical pharmacological active doses, exposure in mouse infection models and expected human PK. The PK profiles of MHAA4549A and its related antibody showed a linear bi-exponential disposition in mice and cynomolgus monkeys. In mice, clearance and half-life ranged from 5.77 to 9.98 mL/day/kg and 10.2 to 5.76 days, respectively. In cynomolgus monkeys, clearance and half-life ranged from 4.33 to 4.34 mL/day/kg and 11.3 to 11.9 days, respectively. The predicted clearance in humans was ~2.60 mL/day/kg. A single intravenous dose ranging from 15 to 45 mg/kg was predicted to achieve efficacious exposure in humans. In conclusion, the PK of MHAA4549A was as expected for a human IgG1 monoclonal antibody that lacks known endogenous host targets. The predicted clearance and projected efficacious doses in humans for MHAA4549A have been verified in a Phase 1 study and Phase 2a study, respectively.  相似文献   
82.
BackgroundObesity has become a major global health challenge due to its increasing prevalence, and the associated health risk. It is the main cause of various metabolic diseases including diabetes, hypertension, cardiovascular disease, stroke and certain forms of cancer.

Methods and Results

In the present study we evaluated the anti-obesity property of Daesiho-tang (DSHT), an herbal medicine, using high fat diet (HFD)-induced obese mice as a model. Our results showed that DSHT ameliorated body weight gain, decreased total body fat, regulated expression of leptin and adiponectin genes of adipose tissue and exerted an anti-diabetic effect by attenuating fasting glucose level and serum insulin level in HFD-fed animals. In addition, DSHT-treatment significantly reduced total cholesterol (TC), triglycerides (TG) and increased high density lipoprotein-cholesterol (HDL), glutamic pyruvic transaminase (GPT) and glutamic oxaloacetic transaminase (GOT) levels in serum and reduced deposition of fat droplets in liver. DSHT treatment resulted in significantly increased relative abundance of bacteria including Bacteroidetes, Bacteroidetes/Firmicutes ratio, Akkermansia Bifidobacterium., Lactobacillus, and decreased the level of Firmicutes. Using RT2 profiler PCR array, 39 (46%) genes were found to be differentially expressed in HFD-fed mice compared to normal control. However, normal gene expressions were restored in 36 (92%) genes of HFD-fed mice, when co-exposed to DSHT.

Conclusion/Major Findings

The results of this study demonstrated that DSHT is an effective herbal formulation in attenuation of obesity in HFD-fed mice through alteration of gene expressions and modulation of intestinal microbiota.  相似文献   
83.
BackgroundWe investigated the efficacy, safety and cost of lime wash of household walls plus treatment of sand fly breeding places with bleach (i.e. environmental management or EM), insecticide impregnated durable wall lining (DWL), and bed net impregnation with slow release insecticide (ITN) for sand fly control in the Indian sub-continent.MethodsThis multi-country cluster randomized controlled trial had 24 clusters in each three sites with eight clusters per high, medium or low sand fly density stratum. Every cluster included 45–50 households. Five households from each cluster were randomly selected for entomological measurements including sand fly density and mortality at one, three, nine and twelve months post intervention. Household interviews were conducted for socioeconomic information and intervention acceptability assessment. Cost for each intervention was calculated. There was a control group without intervention.FindingsSand fly mortality [mean and 95%CI] ranged from 84% (81%-87%) at one month to 74% (71%-78%) at 12 months for DWL, 75% (71%-79%) at one month to 49% (43%-55%) at twelve months for ITN, and 44% (34%-53%) at one month to 22% (14%-29%) at twelve months for EM. Adjusted intervention effect on sand fly density measured by incidence rate ratio ranged from 0.28 (0.23–0.34) at one month to 0.62 (0.51–0.75) at 12 months for DWL; 0.72 (0.62–0.85) at one month to 1.02 (0.86–1.22) at 12 months for ITN; and 0.89 (0.76–1.03) at one months to 1.49 (1.26–1.74) at 12 months for EM. Household acceptance of EM was 74% compared to 94% for both DWL and ITN. Operational cost per household in USD was about 5, 8, and 2 for EM, DWL and ITN, respectively. Minimal adverse reactions were reported for EM and ITN while 36% of households with DWL reported transient itching.InterpretationDWL is the most effective, durable and acceptable control method followed by ITN. The Visceral Leishmaniasis (VL) Elimination Program in the Indian sub-continent should consider DWL and ITN for sand fly control in addition to IRS.  相似文献   
84.
K-Ras is a membrane-associated GTPase that cycles between active and inactive conformational states to regulate a variety of cell signaling pathways. Somatic mutations in K-Ras are linked to 15–20% of all human tumors. K-Ras attaches to the inner leaflet of the plasma membrane via a farnesylated polybasic domain; however, the structural details of the complex remain poorly understood. Based on extensive (7.5 μs total) atomistic molecular dynamics simulations here we show that oncogenic mutant K-Ras interacts with a negatively charged lipid bilayer membrane in multiple orientations. Of these, two highly populated orientations account for ∼54% of the conformers whose catalytic domain directly interacts with the bilayer. In one of these orientation states, membrane binding involves helices 3 and 4 of the catalytic domain in addition to the farnesyl and polybasic motifs. In the other orientation, β-strands 1–3 and helix 2 on the opposite face of the catalytic domain contribute to membrane binding. Flexibility of the linker region was found to be important for the reorientation. The biological significance of these observations was evaluated by initial experiments in cells overexpressing mutant K-Ras as well as by an analysis of Ras-effector complex structures. The results suggest that only one of the two major orientation states is capable of effector binding. We propose that the different modes of membrane binding may be exploited in structure-based drug design efforts for cancer therapy.  相似文献   
85.
The mitochondrial matrix protease CLPP plays a central role in the activation of the mitochondrial unfolded protein response (UPRmt) in Caenorhabditis elegans. Far less is known about mammalian UPRmt signaling, although similar roles were assumed for central players, including CLPP. To better understand the mammalian UPRmt signaling, we deleted CLPP in hearts of DARS2‐deficient animals that show robust induction of UPRmt due to strong dysregulation of mitochondrial translation. Remarkably, our results clearly show that mammalian CLPP is neither required for, nor it regulates the UPRmt in mammals. Surprisingly, we demonstrate that a strong mitochondrial cardiomyopathy and diminished respiration due to DARS2 deficiency can be alleviated by the loss of CLPP, leading to an increased de novo synthesis of individual OXPHOS subunits. These results question our current understanding of the UPRmt signaling in mammals, while introducing CLPP as a possible novel target for therapeutic intervention in mitochondrial diseases.  相似文献   
86.
Juvenile hormone (JH) analogs are nowadays in use to control harmful pests. In order to develop new bioactive molecules as potential pesticides, we have incorporated different active structural features like sulfonamide, aromatic rings, amide group, and amino acid moiety to the base structure. We have screened a series of designed novel JH analogs against JH receptor protein (jhbpGm-2RCK) of Galleria mellonella in comparison to commercial insect growth regulators (IGRs) – Pyriproxyfen (T1) and Fenoxycarb (T2). All analogs exhibit the binding energy profile comparable to commercial IGRs. Based upon these results, a series of sulfonamide-based JHAs (T3–T8) as IGRs have been synthesized and characterized. Further, the efficacy of synthesized analogs (T3–T8) and commercial IGRs (Pyriproxyfen and Fenoxycarb) has been assessed against fourth instars larvae of G. mellonella under the laboratory conditions. LC50 values of all the analogs (T1–T8) against the fourth instars larvae were 9.99, 10.12, 24.76, 30.73, 38.45, 34.15, 34.14, 19.48 ppm and the LC90 153.27, 131.69, 112.15, 191.46, 427.02, 167.13, 217.10, 172.00 ppm, respectively. Among these analogs, N-(1-isopropyl-2-oxo-3-aza-3-N-ethyl-pentanyl)-p-toluene sulfonamide (T8) and N-(1-isopropyl-2-oxo-3-aza-3-N-ethyl-pentanyl) benzene sulfonamide (T7) exhibited the good pest larval mortality at different exposure periods (in hours) and different concentrations (in ppm) in comparison to in use IGRs- T1 and T2. Bio assay results are supported by docking at higher concentration. The present investigation clearly exhibits that analog T8 could serve as a potential IGR in comparison to in use IGRs (T1 and T2). The results are promising and provide new array of synthetic chemicals that may be utilized as IGRs.  相似文献   
87.
88.
Conversion of CO2 to energy‐rich chemicals using renewable energy is of much interest to close the anthropogenic carbon cycle. However, the current photoelectrochemical systems are still far from being practically feasible. Here the successful demonstration of a continuous, energy efficient, and scalable solar‐driven CO2 reduction process based on earth‐abundant molybdenum disulfide (MoS2) catalyst, which works in synergy with an inexpensive hybrid electrolyte of choline chloride (a common food additive for livestock) and potassium hydroxide (KOH) is reported. The CO2 saturated hybrid electrolyte utilized in this study also acts as a buffer solution (pH ≈ 7.6) to adjust pH during the reactions. This study reveals that this system can efficiently convert CO2 to CO with solar‐to‐fuel and catalytic conversion efficiencies of 23% and 83%, respectively. Using density functional theory calculations, a new reaction mechanism in which the water molecules near the MoS2 cathode act as proton donors to facilitate the CO2 reduction process by MoS2 catalyst is proposed. This demonstration of a continuous, cost‐effective, and energy efficient solar driven CO2 conversion process is a key step toward the industrialization of this technology.  相似文献   
89.
Deep terrestrial subsurface represents a huge repository of global prokaryotic biomass. Given its vastness and importance, microbial life within the deep subsurface continental crust remains under-represented in global studies. We characterize the microbial communities of deep, extreme and oligotrophic realm hosted by crystalline Archaean granitic rocks underneath the Deccan Traps, through sampling via 3000 m deep scientific borehole at Koyna, India through metagenomics, amplicon sequencing and cultivation-based analyses. Gene sequences 16S rRNA (7.37 × 106) show considerable bacterial diversity and the existence of a core microbiome (5724 operational taxonomic units conserved out of a total 118,064 OTUs) across the depths. Relative abundance of different taxa of core microbiome varies with depth in response to prevailing lithology and geochemistry. Co-occurrence network analysis and cultivation attempt to elucidate close interactions among autotrophic and organotrophic bacteria. Shotgun metagenomics reveals a major role of autotrophic carbon fixation via the Wood–Ljungdahl pathway and genes responsible for energy and carbon metabolism. Deeper analysis suggests the existence of an ‘acetate switch’, coordinating biosynthesis and cellular homeostasis. We conclude that the microbial life in the nutrient- and energy-limited deep granitic crust is constrained by the depth and managed by a few core members via a close interplay between autotrophy and organotrophy.  相似文献   
90.
Microtubule associated tumor suppressor 1 (MTUS1) has been recognized as a tumor suppressor gene in multiple cancers. However, the molecular mechanisms underlying the regulation of MTUS1 are yet to be investigated. This study aimed to clarify the significance of DNA methylation in silencing MTUS1 expression. We report that MTUS1 acts as tumor suppressor in non-small cell lung carcinoma (NSCLC). Analysis of in silico database and subsequent knockdown of DNMT1 suggested an inverse correlation between DNMT1 and MTUS1 function. Interestingly, increased methylation at MTUS1 promoter is associated with low expression of MTUS1. Treatment with DNA methyltransferases (DNMTs) inhibitor, 5-aza-2′-deoxycytidine (AZA) leads to both reduced promoter methylation accompanied with enrichment of H3K9Ac and enhanced MTUS1 expression. Remarkably, knockdown of MTUS1 showed increased proliferation and migration of NSCLC cells in contrast to diminished proliferation and migration, upon treatment with AZA. We concluded that low expression of MTUS1 correlates to DNA methylation and histone deacetylation in human NSCLC.  相似文献   
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