Abstract Mature heart valves are complex structures consisting of three highly organized extracellular matrix layers primarily composed of collagens, proteoglycans and elastin. Collectively, these ...diverse matrix components provide all the necessary biomechanical properties for valve function throughout life. In contrast to healthy valves, myxomatous valve disease is the most common cause of mitral valve prolapse in the human population and is characterized by an abnormal abundance of proteoglycans within the valve tri-laminar structure. Despite the clinical significance, the etiology of this phenotype is not known. Scleraxis (Scx) is a basic-helix–loop–helix transcription factor that we previously showed to be required for establishing heart valve structure during remodeling stages of valvulogenesis. In this study, we report that remodeling heart valves from Scx null mice express decreased levels of proteoglycans, particularly chondroitin sulfate proteoglycans (CSPGs), while overexpression in embryonic avian valve precursor cells and adult porcine valve interstitial cells increases CSPGs. Using these systems we further identify that Scx is positively regulated by canonical Tgfβ2 signaling during this process and this is attenuated by MAPK activity. Finally, we show that Scx is increased in myxomatous valves from human patients and mouse models, and overexpression in human mitral valve interstitial cells modestly increases proteoglycan expression consistent with myxomatous mitral valve phenotypes. Together, these studies identify an important role for Scx in regulating proteoglycans in embryonic and mature valve cells and suggest that imbalanced regulation could influence myxomatous pathogenesis.
Colorectal cancer (CRC) is the second most common cause of death worldwide, affecting approximately 1.9 million individuals in 2020. Therapeutics of the disease are not yet available and discovering ...a novel anticancer drug candidate against the disease is an urgent need. Thymidylate synthase (TS) is an important enzyme and prime precursor for DNA biosynthesis that catalyzes the methylation of deoxyuridine monophosphate (dUMP) to deoxythymidine monophosphate (dTMP) that has emerged as a novel drug target against the disease. Elevated expression of TS in proliferating cells promotes oncogenesis as well as CRC. Therefore, this study aimed to identify potential natural anticancer agents that can inhibit the activity of the TS protein, subsequently blocking the progression of colorectal cancer. Initially, molecular docking was implied on 63 natural compounds identified from
and
to evaluate their binding affinity to the desired protein. Subsequently, molecular dynamics (MD) simulation, ADME (Absorption, Distribution, Metabolism, and Excretion), toxicity, and quantum chemical-based DFT (density-functional theory) approaches were applied to evaluate the efficacy of the selected compounds. Molecular docking analysis initially identified four compounds (PubChem CID: 5281349, CID: 102004710, CID: 11969465, CID: 198912) that have better binding affinity to the target protein. The ADME and toxicity properties indicated good pharmacokinetics (PK) and toxicity ability of the selected compounds. Additionally, the quantum chemical calculation of the selected molecules found low chemical reactivity indicating the bioactivity of the drug candidate. The global descriptor and HOMO-LUMO energy gap values indicated a satisfactory and remarkable profile of the selected molecules. Furthermore, MD simulations of the compounds identified better binding stability of the compounds to the desired protein. To sum up, the phytoconstituents from two plants showed better anticancer activity against TS protein that can be further developed as an anti-CRC drug.
To evaluate a delivery strategy for newborn interventions in rural Bangladesh.
A cluster-randomized controlled trial was conducted in Mirzapur, Bangladesh. Twelve unions were randomized to ...intervention or comparison arm. All women of reproductive age were eligible to participate. In the intervention arm, community health workers identified pregnant women; made two antenatal home visits to promote birth and newborn care preparedness; made four postnatal home visits to negotiate preventive care practices and to assess newborns for illness; and referred sick neonates to a hospital and facilitated compliance. Primary outcome measures were antenatal and immediate newborn care behaviours, knowledge of danger signs, care seeking for neonatal complications, and neonatal mortality.
A total of 4616 and 5241 live births were recorded from 9987 and 11153 participants in the intervention and comparison arm, respectively. High coverage of antenatal (91% visited twice) and postnatal (69% visited on days 0 or 1) home visitations was achieved. Indicators of care practices and knowledge of maternal and neonatal danger signs improved. Adjusted mortality hazard ratio in the intervention arm, compared to the comparison arm, was 1.02 (95% CI: 0.80-1.30) at baseline and 0.87 (95% CI: 0.68-1.12) at endline. Primary causes of death were birth asphyxia (49%) and prematurity (26%). No adverse events associated with interventions were reported.
Lack of evidence for mortality impact despite high program coverage and quality assurance of implementation, and improvements in targeted newborn care practices suggests the intervention did not adequately address risk factors for mortality. The level and cause-structure of neonatal mortality in the local population must be considered in developing interventions. Programs must ensure skilled care during childbirth, including management of birth asphyxia and prematurity, and curative postnatal care during the first two days of life, in addition to essential newborn care and infection prevention and management.
Clinicaltrials.gov NCT00198627.
Growth hormone (GH) gene transfer can markedly increase growth in transgenic fish. In the present study we have developed a transcriptional assay to evaluate GH-signal activation (GHSA) in zebrafish ...embryos. By analyzing the transcription of c-fos and igf1, and the promoter activity of spi2.1, in zebrafish embryos injected with different constructs, we found that overexpression of either GH or growth hormone receptor (GHR) resulted in GHSA, while a synergetic overexpression of GH and GHR gave greater activation. Conversely, overexpression of a C-terminal truncated dominant-negative GHR (ΔC-GHR) efficiently blocked GHSA epistatic to GH overexpression, demonstrating the requirement for a full GHR homodimer in signaling. In view of the importance of signal-competent GHR dimerization by extracellular GH, we introduced into zebrafish embryos a constitutively activated GHR (CA-GHR) construct, which protein products constitutively dimerize the GHR productively by Jun-zippers to activate downstream signaling in vitro. Importantly, overexpression of CA-GHR led to markedly higher level of GHSA than the synergetic overexpression of GH and GHR. CA-GHR transgenic zebrafish were then studied in a growth trial. The transgenic zebrafish showed higher growth rate than the control fish, which was not achievable by GH transgenesis in these zebrafish. Our study demonstrates GH-independent growth by CA-GHR in vivo which bypasses normal IGF-1 feedback control of GH secretion. This provides a novel means of producing growth enhanced transgenic animals based on molecular protein design.
Microalgae biomass is considered an important feedstock for biofuels and other bioactive compounds due to its faster growth rate, high biomass production and high biomolecules accumulation over first ...and second-generation feedstock. This research aimed to maximize the specific growth rate of fresh water green microalgae Closteriopsis acicularis, a member of family Chlorellaceae under the effect of pH and phosphate concentration to attain enhanced biomass productivity. This study investigates the individual and cumulative effect of phosphate concentration and pH on specific growth characteristics of Closteriopsis acicularis in autotrophic mode of cultivation for bioethanol production. Central-Composite Design (CCD) strategy and Response Surface Methodology (RSM) was used for the optimization of microalga growth and ethanol production under laboratory conditions. The results showed that high specific growth rate and biomass productivity of 0.342 day−1 and 0.497 g L−1 day−1 respectively, were achieved at high concentration of phosphate (0.115 g L−1) and pH (9) at 21st day of cultivation. The elemental composition of optimized biomass has shown enhanced elemental accumulation of certain macro (C, O, P) and micronutrients (Na, Mg, Al, K, Ca and Fe) except for nitrogen and sulfur. The Fourier transform infrared spectroscopic analysis has revealed spectral peaks and high absorbance in spectral range of carbohydrates, lipids and proteins, in optimized biomass. The carbohydrates content of optimized biomass was observed as 58%, with 29.3 g L−1 of fermentable sugars after acid catalyzed saccharification. The bioethanol yield was estimated as 51 % g ethanol/g glucose with maximum of 14.9 g/L of bioethanol production. In conclusion, it can be inferred that high specific growth rate and biomass productivity can be achieved by varying levels of phosphate concentration and pH during cultivation of Closteriopsis acicularis for improved yield of microbial growth, biomass and bioethanol production.
The objective of this study was to improve the dissolution and solubility of dexibuprofen (DEX) using hydroxypropyl beta cyclodextrin (HPβCD) inclusion complexes and also to evaluate the effect of ...presence of hydrophilic polymers on solubilization efficiency of HPβCD. Three different methods (physical trituration, kneading and solvent evaporation) were used to prepare binary inclusion complexes at various drug-to-cyclodextrin weight ratios. An increase in solubility and drug release was observed with the kneading (KN) method at a DEX/HPβCD (1:4) weight ratio. The addition of hydrophilic polymers poloxamer-188 (PXM-188) and poloxamer-407 (PXM-407) at 2.5, 5.0, 10.0 and 20%
enhanced the complexation efficiency and solubility of DEX/HPβCD significantly. Fourier-transform infrared (FTIR) analysis revealed that DEX was successfully incorporated into the cyclodextrin cavity. Differential scanning calorimetry (DSC) and X-ray diffractometry (XRD) revealed less crystallinity of the drug and its entrapment in the cyclodextrin molecular cage. The addition of PXM-188 or PXM-407 reduced the strength of the DEX endothermic peak. With the addition of hydrophilic polymers, sharp and intense peaks of DEX disappeared. Finally, it was concluded that PXM-188 at a weight ratio of 10.0%
was the best candidate for improving solubility, stability and release rate of DEX.
To estimate the validity (sensitivity, specificity, and positive and negative predictive values) of a clinical algorithm as used by community health workers (CHWs) to detect and classify neonatal ...illness during routine household visits in rural Bangladesh.
CHWs evaluated breastfeeding and symptoms and signs of illness in 395 neonates selected randomly from neonatal illness surveillance during household visits on postnatal days 0, 2, 5 and 8. Neonates classified with very severe disease (VSD) were referred to a community-based hospital. Within 12 hours of CHW assessments, physicians independently evaluated all neonates seen in a given day by one CHW, randomly chosen from among 36 project CHWs. Physicians recorded symptoms and signs of illness, classified the illness, and determined whether the newborn needed referral-level care at the hospital. Physicians' identification and classification were used as the gold standard in determining the validity of CHWs' identification of symptoms and signs of illness and its classification.
CHWs' classification of VSD showed a sensitivity of 73%, a specificity of 98%, a positive predictive value of 57% and a negative predictive value of 99%. A maternal report of any feeding problem as ascertained by physician questioning was significantly associated (P < 0.001) with 'not sucking at all' and 'not attached at all' or 'not well attached' as determined clinically by CHWs during feeding assessment.
CHWs identified with high validity the neonates with severe illness needing referral-level care. Home-based illness recognition and management, including referral of neonates with severe illness by CHWs, is a promising strategy for improving neonatal health and survival in low-resource developing country settings.
Bacillus strains are broadly studied for their beneficial role in plant growth and biological control of plant disease and pest; however, little is known about their underlying mechanisms. In this ...study, we assessed the controlling and defence‐related mechanisms of three Bacillus strains including rice seed‐associated strain B. subtilis A15, rhizobacterial strains B. amyloliquefaciens D29 and B. methylotrophicus H8, all of which are against bacterial leaf blight (BLB) caused by Xanthomonas oryzae pv. oryzae. Results indicated that all three strains showed strong biofilm formation ability. The culture filtrates of each strain significantly suppressed the growth and biofilm formation of X. oryzae, while changes in bacterial cell morphology such as cell swell and severe cell wall alterations were observed through the transmission electron microscopy images. PCR analysis revealed that all three strains harbour the antimicrobial‐associated genes that are responsible for biosynthesis of bacillomycin, fengycin, iturin and surfactin. Subsequent real‐time qPCR analysis revealed the upregulated expression of fenD and srfAA genes in D29 and H8, and fenD and ituC genes in A15 during their in vitro interaction with X. oryzae. It suggests that the antibacterial mechanisms of the three strains may be at least partially associated with their ability to secrete corresponding lipopeptides. Interestingly, the applications of the three strains in greenhouse conditions were found to be effective in controlling the BLB disease, which was achieved through the activation of inducing systemic resistance resulted from the enhanced activities of defence‐related enzymes. This is the first report of demonstration of the mode of antibacterial effect of Bacillus strains against X. oryzae. Overall, data from the current study provide valuable information for biological control of BLB disease in rice.
This study was conducted to assess efficacy of biological control against bacterial leaf blight (BLB) of rice produced by Xanthomonas oryzae pv. oryzae. Five endophytic strains (A1, A2, A3, A13 and ...A15) and two rhizospherial Bacilli (D29 and H8) were tested for their antagonistic activities against BLB in vitro and in vivo. All seven strains showed high potential of antagonistic activity against X. oryzae pv. oryzae and three phytopathogenic fungi in vitro. Test of 16SrRNA gene sequence were assigned isolates A1, A3 and A13 as Bacillus amyloliquefaciens while isolates A2 and A15 as B. methylotrophicus and B. subtilis, respectively. In greenhouse, four strains of displayed 50.29%-57.86% inhibition rate against the pathogen and significantly increased plant fresh weight from 50.03% to 73.11% and dry weight from 64.11% to 86.65% in treated rice plants. In addition, these strains demonstrated strong capability to produce indole-3-acetic acid, siderophores, solubilizing phosphate and also colonize roots. Real-time quantitative polymerase chain reaction revealed that expression of defense-related genes including OsAOS2, OsJMT1, OsNPR1 and OsPR1b were significantly up-regulated in leaves of D29-exposed rice plants, suggesting that treatment of rice with D29 suppressed BLB through systemic activation of the plant defense system. Therefore, data suggest that Bacillus isolates A13, A15, D29 and H8 support effective antagonistic activity against BLB under greenhouse conditions in addition to their potential to promote growth of rice plants.
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