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1.
Glycobiology ; 34(2)2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38039077

RESUMO

Phosphatidyl-myo-inositol mannosides (PIMs), Lipomannan (LM), and Lipoarabinomannan (LAM) are essential components of the cell envelopes of mycobacteria. At the beginning of the biosynthesis of these compounds, phosphatidylinositol (PI) is mannosylated and acylated by various enzymes to produce Ac1/2PIM4, which is used to synthesize either Ac1/2PIM6 or LM/LAM. The protein PimE, a membrane-bound glycosyltransferase (GT-C), catalyzes the addition of a mannose group to Ac1PIM4 to produce Ac1PIM5, using polyprenolphosphate mannose (PPM) as the mannose donor. PimE-deleted Mycobacterium smegmatis (Msmeg) showed structural deformity and increased antibiotic and copper sensitivity. Despite knowing that the mutation D58A caused inactivity in Msmeg, how PimE catalyzes the transfer of mannose from PPM to Ac1/2PIM4 remains unknown. In this study, analyzing the AlphaFold structure of PimE revealed the presence of a tunnel through the D58 residue with two differently charged gates. Molecular docking suggested PPM binds to the hydrophobic tunnel gate, whereas Ac1PIM4 binds to the positively charged tunnel gate. Molecular dynamics (MD) simulations further demonstrated the critical roles of the residues N55, F87, L89, Y163, Q165, K197, L198, R251, F277, W324, H326, and I375 in binding PPM and Ac1PIM4. The mutation D58A caused a faster release of PPM from the catalytic tunnel, explaining the loss of PimE activity. Along with a hypothetical mechanism of mannose transfer by PimE, we also observe the presence of tunnels through a negatively charged aspartate or glutamate with two differently-charged gates among most GT-C enzymes. Common hydrophobic gates of GT-C enzymes probably harbor sugar donors, whereas, differently-charged tunnel gates accommodate various sugar-acceptors.


Assuntos
Simulação de Dinâmica Molecular , Mycobacterium , Manose/química , Simulação de Acoplamento Molecular , Mycobacterium smegmatis/genética , Mycobacterium smegmatis/metabolismo , Lipopolissacarídeos/química
2.
J Am Chem Soc ; 146(4): 2568-2573, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38230667

RESUMO

Chemical separations are expensive, consuming 10-15% of humanity's global energy budget. Many current separation methods employ thermal energy for distillation, often through the combustion of carbon-containing fuels, or extractions and crystallizations from organic solvents, which must then be discarded or redistilled, with a substantial energetic cost. The direct use of renewable energy sources, such as light, could enable the development of novel separations processes, as is required for the transition away from fossil fuel use. Metal-organic capsules, which can selectively bind molecules from mixtures, can provide the foundation for these novel separations processes. Here we report a tetrahedral metal-organic capsule bearing light-responsive diazo moieties around its metal-ion vertices. This capsule can be used to selectively separate progesterone from a mixture of steroids in a process driven by visible light energy. Our process combines biphasic extraction and selective binding of progesterone with the light-driven release of this molecule in purified form. Ultimately, our process might be adapted to the purifications of the many other fine chemical products that are bound selectively by capsules.

3.
J Am Chem Soc ; 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36753330

RESUMO

A strategy for light-powered guest release from a tetrahedral capsule has been developed by incorporating azobenzene units at its vertices. A new Zn4L4 tetrahedral capsule bearing 12 diazo moieties at its metal-ion vertices was prepared from a phenyldiazenyl-functionalized subcomponent and a central trialdehyde panel. Ultraviolet irradiation caused isomerization of the peripheral diazo groups from the thermodynamically preferred trans configuration to the cis form, thereby generating steric clash and resulting in cage disassembly and concomitant guest release. Visible-light irradiation drove cage re-assembly following re-isomerization of the diazo groups to the trans form, resulting in guest re-uptake. A detailed 19F NMR study elucidated how switching led to guest release: each metal vertex tolerated only one cis-azobenzene moiety, with further isomerization leading to cage disassembly.

4.
Transfusion ; 63(9): 1747-1757, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37427683

RESUMO

BACKGROUND: Red Blood cells (RBCs) bring about harmful consequences during storage. MicroRNA (miRNA) dysregulation in stored RBCs could represent potential biomarkers of storage lesions. Although leukoreduction prevents damage to RBCs, it is uncertain whether leukoreduction of RBCs would impact the dysregulation of miRNAs during storage. This study evaluated the potential role of miRNAs for any alteration of leukoreduced (LR) and non-leukoreduced (NLR) RBCs till 21 days of storage. STUDY DESIGN AND METHODS: In this prospective study, thirty male volunteers' blood was equally divided into leukoreduced RBCs (LR) and NLR RBC (NLR) bags and stored till Day 21 at 4-60c. Selected miRNAs were quantified on Days 0 and 21. Further, bioinformatic tools were used to analyze the selected miRNAs and their predicted target genes (mRNAs) and identify the miRNA-mRNA regulatory relationships. RESULTS: A significantly higher fold change values of three miRNAs (miR-96-5p, miR-197-3p, miR-769-3p) were observed in NLR RBCs (p < .05). A significantly higher (p < .05) expression levels of miR-150-5p and miR-197-3p were observed in NLR RBCs till 21 days of storage. Further, the correlation with mRNA quantification confirmed the regulatory role of these miRNAs upon functional pathway enrichment analysis. DISCUSSION: A higher level of dysregulation of miRNAs was observed in NLR RBCs. Validation from In-Silico analysis suggested the regulatory role of miRNAs in cell apoptosis, senescence, and RBC-related signaling pathways. This indicated that stored LR RBCs would likely have better in vivo survival and function following transfusion. However, an in vivo study of miRNA in RBCs is warranted for conclusive evidence.


Assuntos
MicroRNAs , Humanos , Masculino , MicroRNAs/metabolismo , Preservação de Sangue , Estudos Prospectivos , Eritrócitos/metabolismo
5.
Mol Plant Microbe Interact ; 35(2): 131-145, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34689599

RESUMO

Root nodule symbiosis (RNS) is the pillar behind sustainable agriculture and plays a pivotal role in the environmental nitrogen cycle. Most of the genetic, molecular, and cell-biological knowledge on RNS comes from model legumes that exhibit a root-hair mode of bacterial infection, in contrast to the Dalbergoid legumes exhibiting crack-entry of rhizobia. As a step toward understanding this important group of legumes, we have combined microscopic analysis and temporal transcriptome to obtain a dynamic view of plant gene expression during Arachis hypogaea (peanut) nodule development. We generated comprehensive transcriptome data by mapping the reads to A. hypogaea, and two diploid progenitor genomes. Additionally, we performed BLAST searches to identify nodule-induced yet-to-be annotated peanut genes. Comparison between peanut, Medicago truncatula, Lotus japonicus, and Glycine max showed upregulation of 61 peanut orthologs among 111 tested known RNS-related genes, indicating conservation in mechanisms of nodule development among members of the Papilionoid family. Unlike model legumes, recruitment of class 1 phytoglobin-derived symbiotic hemoglobin (SymH) in peanut indicates diversification of oxygen-scavenging mechanisms in the Papilionoid family. Finally, the absence of cysteine-rich motif-1-containing nodule-specific cysteine-rich peptide (NCR) genes but the recruitment of defensin-like NCRs suggest a diverse molecular mechanism of terminal bacteroid differentiation. In summary, our work describes genetic conservation and diversification in legume-rhizobia symbiosis in the Papilionoid family, as well as among members of the Dalbergoid legumes.[Formula: see text] Copyright © 2022 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.


Assuntos
Arachis , Medicago truncatula , Arachis/genética , Arachis/microbiologia , Diferenciação Celular , Medicago truncatula/microbiologia , Fixação de Nitrogênio/genética , Nódulos Radiculares de Plantas/microbiologia , Simbiose/genética , Transcriptoma/genética
6.
J Am Chem Soc ; 144(29): 13039-13043, 2022 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-35834720

RESUMO

A multicomponent pseudorotaxane quadrilateral was reversibly toggled between three distinct switching states. Switching in the forward conversion was achieved by addition of H+ and K+ ions, and switching in the reverse direction was performed by addition of 18-crown-6 and 1-aza-18-crown-6. In both the forward and backward ways, the inputs operated an AND gate with distinct catalytic outputs. While in the forward direction the logic AND operation starting from a heteroleptic five-component assembly turned "ON" an imine hydrolysis as output (AND-1), in the inverse direction a Michael addition was ignited as the output starting from a seven-component aggregate following the AND gate logic (AND-2).


Assuntos
Rotaxanos , Íons , Lógica
7.
Biochem Biophys Res Commun ; 621: 14-19, 2022 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-35809342

RESUMO

The complex cellular envelope is one of the major reasons behind the survival in hostile conditions and the emergence of the drug-resisting properties of mycobacteria. Phosphatidyl-myo-inositol hexamannoside (PIM6), Lipomannan (LM), and Lipoarabinomannan (LAM) are important structural constituents of the cell envelope and have roles in modulating host immune functions. Phosphatidyl-myo-inositol (PI) is first mannosylated at the 2-position of the inositol group by phosphatidyl-myo-inositol mannosyltransferase A (PimA) to produce phosphatidyl-myo-inositol monomannoside (PIM1). This PIM1 is then further mannosylated at the 6-position of the inositol group by phosphatidyl-myo-inositol mannosyltransferase B' (PimB') utilizing GDP-mannose as the mannose-donor to synthesize phosphatidyl-myo-inositol dimannoside (PIM2) and GDP. Further mannosylation and acylation on PIM2 produce Ac1/2PIM4, which can then be converted to either Ac1/2PIM6 or LM/LAM. Detailed functional mechanism of how PimB' transfers the mannose sugar to PIM1 is not understood. Using molecular docking, the interactions of PimB' with the substrate PIM1 and the product PIM2 are analyzed here. Molecular dynamics (MD) simulations of PimB' with the substrates and the products were performed for 300ns to find out critical residues involved in the mannose-transfer reaction. Docking and MD analyses indicated the residues R206 and R210 bind both PIM1 and PIM2 and are critical in the mannose-transfer reaction. The residues 120HEVGWSMLPGS130 and 281RTRGGGL288 were involved in the transfer of PIM1 from the active site. The residues 18IGG20, K211, E290, G291, 294IV295, and E298 were also important in the mannosylation reaction. The crucial residues obtained from this study may help design novel drugs against mycobacterial PimB'.


Assuntos
Manosiltransferases , Mycobacterium , Proteínas de Bactérias/metabolismo , Inositol , Manose , Simulação de Acoplamento Molecular , Fosfatidilinositóis/metabolismo
8.
New Phytol ; 236(6): 2265-2281, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36098671

RESUMO

Legumes can host nitrogen-fixing rhizobia inside root nodules. In model legumes, rhizobia enter via infection threads (ITs) and develop nodules in which the infection zone contains a mixture of infected and uninfected cells. Peanut (Arachis hypogaea) diversified from model legumes c. 50-55 million years ago. Rhizobia enter through 'cracks' to form nodules in peanut roots where cells of the infection zone are uniformly infected. Phylogenomic studies have indicated symbiosis as a labile trait in peanut. These atypical features prompted us to investigate the molecular mechanism of peanut nodule development. Combining cell biology, genetics and genomic tools, we visualized the status of hormonal signaling in peanut nodule primordia. Moreover, we dissected the signaling modules of Nodule INception (NIN), a master regulator of both epidermal infection and cortical organogenesis. Cytokinin signaling operates in a broad zone, from the epidermis to the pericycle inside nodule primordia, while auxin signaling is narrower and focused. Nodule INception is involved in nodule organogenesis, but not in crack entry. Nodulation Pectate Lyase, which remodels cell walls during IT formation, is not required. By contrast, Nodule enhanced Glycosyl Hydrolases (AhNGHs) are recruited for cell wall modification during crack entry. While hormonal regulation is conserved, the function of the NIN signaling modules is diversified in peanut.


Assuntos
Fabaceae , Rhizobium , Arachis/genética , Nódulos Radiculares de Plantas/microbiologia , Regulação da Expressão Gênica de Plantas , Simbiose/fisiologia , Epiderme/metabolismo , Fixação de Nitrogênio , Proteínas de Plantas/metabolismo , Nodulação/genética
9.
PLoS Comput Biol ; 17(4): e1008860, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33835998

RESUMO

The COVID-19 pandemic is posing an unprecedented threat to the whole world. In this regard, it is absolutely imperative to understand the mechanism of metabolic reprogramming of host human cells by SARS-CoV-2. A better understanding of the metabolic alterations would aid in design of better therapeutics to deal with COVID-19 pandemic. We developed an integrated genome-scale metabolic model of normal human bronchial epithelial cells (NHBE) infected with SARS-CoV-2 using gene-expression and macromolecular make-up of the virus. The reconstructed model predicts growth rates of the virus in high agreement with the experimental measured values. Furthermore, we report a method for conducting genome-scale differential flux analysis (GS-DFA) in context-specific metabolic models. We apply the method to the context-specific model and identify severely affected metabolic modules predominantly comprising of lipid metabolism. We conduct an integrated analysis of the flux-altered reactions, host-virus protein-protein interaction network and phospho-proteomics data to understand the mechanism of flux alteration in host cells. We show that several enzymes driving the altered reactions inferred by our method to be directly interacting with viral proteins and also undergoing differential phosphorylation under diseased state. In case of SARS-CoV-2 infection, lipid metabolism particularly fatty acid oxidation, cholesterol biosynthesis and beta-oxidation cycle along with arachidonic acid metabolism are predicted to be most affected which confirms with clinical metabolomics studies. GS-DFA can be applied to existing repertoire of high-throughput proteomic or transcriptomic data in diseased condition to understand metabolic deregulation at the level of flux.


Assuntos
COVID-19/metabolismo , Pulmão/metabolismo , Modelos Biológicos , SARS-CoV-2 , Algoritmos , Biomassa , Brônquios/metabolismo , Brônquios/virologia , COVID-19/genética , COVID-19/virologia , Células Cultivadas , Biologia Computacional , Células Epiteliais/metabolismo , Células Epiteliais/virologia , Perfilação da Expressão Gênica , Humanos , Pulmão/patologia , Pulmão/virologia , Análise do Fluxo Metabólico/estatística & dados numéricos , Redes e Vias Metabólicas/genética , Metabolômica , Pandemias , Fosforilação , Mapas de Interação de Proteínas , SARS-CoV-2/crescimento & desenvolvimento , SARS-CoV-2/patogenicidade , Transcriptoma
10.
J Appl Microbiol ; 133(6): 3605-3616, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36000378

RESUMO

AIMS: The present study aimed to document the comparative analysis of differential hypervirulent features of Vibrio cholerae O1 strains isolated during 2018 from cholera endemic regions in Gujarat and Maharashtra (Western India) and West Bengal (Eastern India). METHODS AND RESULTS: A total of 87 V. cholerae O1 clinical strains from Western India and 48 from Eastern India were analysed for a number of biotypic and genotypic features followed by antimicrobial resistance (AMR) profile. A novel polymerase chain reaction was designed to detect a large fragment deletion in the Vibrio seventh pandemic island II (VSP-II) genomic region, which is a significant genetic feature of the V. cholerae strains that have caused Yemen cholera outbreak. All the strains from Western India belong to the Ogawa serotype, polymyxin B-sensitive, hemolytic, had a deletion in VSP-II (VSP-IIC) region and carried Haitian genetic alleles of ctxB, tcpA and rtxA. Conversely, 14.6% (7/48) of the strains from Eastern India belonged to the Inaba serotype, polymyxin B-resistant, nonhemolytic, harboured VSP-II other than VSP-IIC type, classical ctxB, Haitian tcpA and El Tor rtxA alleles. Resistance to tetracycline and chloramphenicol has been observed in strains from both regions. CONCLUSIONS: This study showed hypervirulent, polymyxin B-sensitive epidemic causing strains in India along with the strains with polymyxin B-resistant and nonhemolytic traits that may spread and cause serious disease outcomes in future. SIGNIFICANCE AND IMPACT OF THE STUDY: The outcomes of this study can help to improve the understanding of the hyperpathogenic property of recently circulating pandemic Vibrio cholerae strains in India. Special attention is also needed for the monitoring of AMR surveillance because V. cholerae strains are losing susceptibility to many antibiotics used as a second line of defence in the treatment of cholera.


Assuntos
Cólera , Vibrio cholerae O1 , Humanos , Vibrio cholerae O1/genética , Cólera/epidemiologia , Cólera/tratamento farmacológico , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Polimixina B/farmacologia , Haiti , Farmacorresistência Bacteriana/genética , Índia/epidemiologia , Genótipo , Surtos de Doenças , Toxina da Cólera/genética , Toxina da Cólera/uso terapêutico
11.
Nanomedicine ; 40: 102487, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34740869

RESUMO

Induced pluripotent stem cells (iPSCs) are a promising cell source for regenerative medicine. However, their feeder-free maintenance in undifferentiated states remains challenging. In recent past extensive studies have been directed using pristine or functionalized carbon nanotube in tissue engineering. Here we proposed thin films of functionalized carbon nanotubes (OH-single-walled CNTs [SWCNTs] and OH-multiwalled CNTs [MWCNTs]), as alternatives for the feeder-free in vitro culture of canine iPSCs (ciPSCs), considered as the cellular model. The ciPSC colonies could maintain their dome-shaped compactness and other characteristics when propagated on CNT films. Concomitantly, high cell viability and upregulation of pluripotency-associated genes and cell adhesion molecules were observed, further supported by molecular docking. Moreover, CNTs did not have profound toxic effects compared to feeder cultures as evident by cytocompatibility studies. Further, cardiac and neuronal differentiation of ciPSCs was induced on these films to determine their influence on the differentiation process. The cells retained differentiation potential and the nanotopographical features of the substrates provided positive cues to enhance differentiation to both lineages as evident by immunocytochemical staining and marker gene expression. Overall, OH-SWCNT provided better cues, maintained pluripotency, and induced the differentiation of ciPSCs. These results indicate that OH-functionalized CNT films could be used as alternatives for the feeder-free maintenance of ciPSCs towards prospective utilization in regenerative medicine.


Assuntos
Células-Tronco Pluripotentes Induzidas , Nanotubos de Carbono , Animais , Diferenciação Celular/fisiologia , Cães , Simulação de Acoplamento Molecular , Nanotubos de Carbono/química , Estudos Prospectivos
12.
Angew Chem Int Ed Engl ; 61(48): e202212473, 2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-36197751

RESUMO

The heteroleptic multi-component double slider-on-deck system DS3 exhibits tight coupling of motional speed of two distinct nano-circular sliders (k298 =77 and 41 kHz) despite a 2.2 nm separation. In comparison, the single sliders in DS1 and DS2 move at vastly different speed (k298 =1.1 vs. 350 kHz). Synchronization of the motions in DS3 remains even when one slows the movement of the faster slider using small molecular brake pads. In contrast to the individual DS1 and DS2 systems, DS3 is a powerful catalyst for a two-step reaction by using the motion of both sliders to drive two catalytic processes.

13.
J Am Chem Soc ; 143(14): 5319-5323, 2021 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-33787253

RESUMO

A 3-fold completive self-sorted library of dynamic motifs was integrated into the design of the pseudorotaxane-based rotor [Zn(2·H+)(3)(4)]2+ operating at k298 = 15.4 kHz. The rotational motion in the five-component device is based on association/dissociation of the pyridyl head of the pseudorotaxane rotator arm between two zinc(II) porphyrin stations. Addition of TFA or 2-cyano-2-phenylpropanoic acid as a chemical fuel to a zinc release system and the loose rotor components 2-4 enabled the liberated zinc(II) ions and protons to act in unison, setting up the rotor through the formation of a heteroleptic zinc complex and a pseudorotaxane linkage. With chemical fuel, the dissipative system was reproducibly pulsed three times without a problem. Due to the double role of the fuel acid, two kinetically distinct processes played a role in both the out-of-equilibrium assembly and disassembly of the rotor, highlighting the complex issues in multitasking of chemical fuels.

14.
J Am Chem Soc ; 143(36): 14926-14935, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34478277

RESUMO

Driving conformational motion in defined off-equilibrium oscillations can be achieved using chemical fuels. When the ultrafast turnstile 1 (k298> 1012 Hz) was fueled with 2-cyano-2-phenylpropanoic acid (Fuel 1), the diprotonated rotor [H2(1)]2+ (k298 = 84.0 kHz) formed as a transient regaining the dynamics of the initial turnstile after consumption of the fuel (135 min). Upon addition of silver(I) (Fuel 2) to turnstile 1, the metastable rotor [Ag2(1)]2+ (k298 = 1.57 Hz) was initially furnished, but due to a consequentially triggered SN2 reaction, the Ag+ ions were consumed as insoluble AgBr along with regeneration of 1 (within 3 h). The off-equilibrium fast ⇆ slow rotor conversions fueled by acid and silver(I) were directly monitored by fluorescence and 1H NMR. In addition, metal ion exchange was fueled enabling off-equilibrium oscillations between rotors [Li2(1)]2+ ⇆ [Ag2(1)]2+. In the end, both sustainability and efficiency of the process were increased in unison by using the interfering proton waste in the formation of a [2]pseudorotaxane.

15.
PLoS Med ; 18(9): e1003680, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34582448

RESUMO

BACKGROUND: Hospitalized preterm infants with compromised skin barrier function treated topically with sunflower seed oil (SSO) have shown reductions in sepsis and neonatal mortality rate (NMR). Mustard oil and products commonly used in high-mortality settings may possibly harm skin barrier integrity and enhance risk of infection and mortality in newborn infants. We hypothesized that SSO therapy may reduce NMR in such settings. METHODS AND FINDINGS: This was a population-based, cluster randomized, controlled trial in 276 clusters in rural Uttar Pradesh, India. All newborn infants identified through population-based surveillance in the study clusters within 7 days of delivery were enrolled from November 2014 to October 2016. Exclusive, 3 times daily, gentle applications of 10 ml of SSO to newborn infants by families throughout the neonatal period were recommended in intervention clusters (n = 138 clusters); infants in comparison clusters (n = 138 clusters) received usual care, such as massage practice typically with mustard oil. Primary analysis was by intention-to-treat with NMR and post-24-hour NMR as the primary outcomes. Secondary analysis included per-protocol analysis and subgroup analyses for NMR. Regression analysis was adjusted for caste, first-visit weight, delivery attendant, gravidity, maternal age, maternal education, sex of the infant, and multiple births. We enrolled 13,478 (52.2% male, mean weight: 2,575.0 grams ± standard deviation [SD] 521.0) and 13,109 (52.0% male, mean weight: 2,607.0 grams ± SD 509.0) newborn infants in the intervention and comparison clusters, respectively. We found no overall difference in NMR in the intervention versus the comparison clusters [adjusted odds ratio (aOR) 0.96, 95% confidence interval (CI) 0.84 to 1.11, p = 0.61]. Acceptance of SSO in the intervention arm was high at 89.3%, but adherence to exclusive applications of SSO was 30.4%. Per-protocol analysis showed a significant 58% (95% CI 42% to 69%, p < 0.01) reduction in mortality among infants in the intervention group who were treated exclusively with SSO as intended versus infants in the comparison group who received exclusive applications of mustard oil. A significant 52% (95% CI 12% to 74%, p = 0.02) reduction in NMR was observed in the subgroup of infants weighing ≤1,500 g (n = 589); there were no statistically significant differences in other prespecified subgroup comparisons by low birth weight (LBW), birthplace, and wealth. No severe adverse events (SAEs) were attributable to the intervention. The study was limited by inability to mask allocation to study workers or participants and by measurement of emollient use based on caregiver responses and not actual observation. CONCLUSIONS: In this trial, we observed that promotion of SSO therapy universally for all newborn infants was not effective in reducing NMR. However, this result may not necessarily establish equivalence between SSO and mustard oil massage in light of our secondary findings. Mortality reduction in the subgroup of infants ≤1,500 g was consistent with previous hospital-based efficacy studies, potentially extending the applicability of emollient therapy in very low-birth-weight (VLBW) infants along the facility-community continuum. Further research is recommended to develop and evaluate therapeutic regimens and continuum of care delivery strategies for emollient therapy for newborn infants at highest risk of compromised skin barrier function. TRIAL REGISTRATION: ISRCTN Registry ISRCTN38965585 and Clinical Trials Registry-India (CTRI/2014/12/005282) with WHO UTN # U1111-1158-4665.


Assuntos
Emolientes/uso terapêutico , Mortalidade Infantil , Óleo de Girassol/uso terapêutico , Administração Tópica , Adulto , Análise por Conglomerados , Feminino , Humanos , Índia/epidemiologia , Lactente , Recém-Nascido , Recém-Nascido Prematuro , Masculino , Massagem , Mostardeira , Óleos de Plantas/uso terapêutico , Creme para a Pele/uso terapêutico , Fatores Socioeconômicos , Óleo de Girassol/administração & dosagem
16.
PLoS Med ; 18(6): e1003644, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34181649

RESUMO

BACKGROUND: Maternal morbidity occurs several times more frequently than mortality, yet data on morbidity burden and its effect on maternal, foetal, and newborn outcomes are limited in low- and middle-income countries. We aimed to generate prospective, reliable population-based data on the burden of major direct maternal morbidities in the antenatal, intrapartum, and postnatal periods and its association with maternal, foetal, and neonatal death in South Asia and sub-Saharan Africa. METHODS AND FINDINGS: This is a prospective cohort study, conducted in 9 research sites in 8 countries of South Asia and sub-Saharan Africa. We conducted population-based surveillance of women of reproductive age (15 to 49 years) to identify pregnancies. Pregnant women who gave consent were include in the study and followed up to birth and 42 days postpartum from 2012 to 2015. We used standard operating procedures, data collection tools, and training to harmonise study implementation across sites. Three home visits during pregnancy and 2 home visits after birth were conducted to collect maternal morbidity information and maternal, foetal, and newborn outcomes. We measured blood pressure and proteinuria to define hypertensive disorders of pregnancy and woman's self-report to identify obstetric haemorrhage, pregnancy-related infection, and prolonged or obstructed labour. Enrolled women whose pregnancy lasted at least 28 weeks or those who died during pregnancy were included in the analysis. We used meta-analysis to combine site-specific estimates of burden, and regression analysis combining all data from all sites to examine associations between the maternal morbidities and adverse outcomes. Among approximately 735,000 women of reproductive age in the study population, and 133,238 pregnancies during the study period, only 1.6% refused consent. Of these, 114,927 pregnancies had morbidity data collected at least once in both antenatal and in postnatal period, and 114,050 of them were included in the analysis. Overall, 32.7% of included pregnancies had at least one major direct maternal morbidity; South Asia had almost double the burden compared to sub-Saharan Africa (43.9%, 95% CI 27.8% to 60.0% in South Asia; 23.7%, 95% CI 19.8% to 27.6% in sub-Saharan Africa). Antepartum haemorrhage was reported in 2.2% (95% CI 1.5% to 2.9%) pregnancies and severe postpartum in 1.7% (95% CI 1.2% to 2.2%) pregnancies. Preeclampsia or eclampsia was reported in 1.4% (95% CI 0.9% to 2.0%) pregnancies, and gestational hypertension alone was reported in 7.4% (95% CI 4.6% to 10.1%) pregnancies. Prolonged or obstructed labour was reported in about 11.1% (95% CI 5.4% to 16.8%) pregnancies. Clinical features of late third trimester antepartum infection were present in 9.1% (95% CI 5.6% to 12.6%) pregnancies and those of postpartum infection in 8.6% (95% CI 4.4% to 12.8%) pregnancies. There were 187 pregnancy-related deaths per 100,000 births, 27 stillbirths per 1,000 births, and 28 neonatal deaths per 1,000 live births with variation by country and region. Direct maternal morbidities were associated with each of these outcomes. CONCLUSIONS: Our findings imply that health programmes in sub-Saharan Africa and South Asia must intensify their efforts to identify and treat maternal morbidities, which affected about one-third of all pregnancies and to prevent associated maternal and neonatal deaths and stillbirths. TRIAL REGISTRATION: The study is not a clinical trial.


Assuntos
Mortalidade Infantil , Mortalidade Materna , Complicações na Gravidez/mortalidade , Natimorto/epidemiologia , Adolescente , Adulto , África Subsaariana/epidemiologia , Ásia/epidemiologia , Feminino , Humanos , Lactente , Recém-Nascido , Gravidez , Complicações na Gravidez/diagnóstico , Resultado da Gravidez , Estudos Prospectivos , Medição de Risco , Fatores de Risco , Adulto Jovem
17.
Biochem J ; 477(7): 1287-1308, 2020 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-32203568

RESUMO

T-cell receptor (TCR) signaling is initiated by recruiting ZAP-70 to the cytosolic part of TCR. ZAP-70, a non-receptor tyrosine kinase, is composed of an N-terminal tandem SH2 (tSH2) domain connected to the C-terminal kinase domain. The ZAP-70 is recruited to the membrane through binding of tSH2 domain and the doubly phosphorylated ITAM motifs of CD3 chains in the TCR complex. Our results show that the tSH2 domain undergoes a biphasic structural transition while binding to the doubly phosphorylated ITAM-ζ1 peptide. The C-terminal SH2 domain binds first to the phosphotyrosine residue of ITAM peptide to form an encounter complex leading to subsequent binding of second phosphotyrosine residue to the N-SH2 domain. We decipher a network of noncovalent interactions that allosterically couple the two SH2 domains during binding to doubly phosphorylated ITAMs. Mutation in the allosteric network residues, for example, W165C, uncouples the formation of encounter complex to the subsequent ITAM binding thus explaining the altered recruitment of ZAP-70 to the plasma membrane causing autoimmune arthritis in mice. The proposed mechanism of allosteric coupling is unique to ZAP-70, which is fundamentally different from Syk, a close homolog of ZAP-70 expressed in B-cells.


Assuntos
Sítio Alostérico , Receptores de Antígenos de Linfócitos T/metabolismo , Linfócitos T/metabolismo , Proteína-Tirosina Quinase ZAP-70/química , Proteína-Tirosina Quinase ZAP-70/metabolismo , Regulação Alostérica , Animais , Artrite Reumatoide/genética , Artrite Reumatoide/metabolismo , Modelos Animais de Doenças , Escherichia coli/genética , Motivo de Ativação do Imunorreceptor Baseado em Tirosina , Camundongos , Simulação de Dinâmica Molecular , Fosforilação , Mutação Puntual , Transdução de Sinais , Quinase Syk/genética , Quinase Syk/metabolismo , Proteína-Tirosina Quinase ZAP-70/genética , Domínios de Homologia de src/genética
18.
J Environ Manage ; 289: 112504, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33839612

RESUMO

This work mainly focused on deforestation susceptibility (DS) assessment and its prediction based on statistical models (FR, LR & AHP) in the Saranda forest, India. Also, efforts had been made to quantify the effect of mining on deforestation. We had considered twenty-five (twenty present and five predicted) causative variables of deforestation, including climate, natural or geomorphological, forestry, topographical, environmental, and anthropogenic. The predicted variables have been generated from different simulation models. Also, very high-resolution, Google Earth imagery have been used in time series analysis for deforestation from 1987 to 2020 data and generated dependent variable. On deforestation analysis, it was observed that a total of 4197.84 ha forest areas were lost in the study region due to illegal mining, agricultural and tribal people allied activities. The DS results have shown that of total existing forest area, 11.22% area were under very high, 16.08% under high, 16.18% under moderate, 24.25% under low, and 32.27% falls very low categories. According to the DS assessment and predicted results, the very high susceptibility classes were found at and close to mines, agricultural, roads and settlement's surrounding sites. The sensitivity analysis results also shown that some causative variables (maximum temperature (2.95%), minimum temperature (0.51%), rainfall (2.69%), LST (4.56%), hot spot (7.36%), aspect (1.14%), NDVI (2.64%), forest density (3.78%), lithology (3.26%), geomorphology (3.00%), distance from agricultural (19.40%), soil type (2.05%), solar radiation (5.97%), LULC (3.26%), drought (3.16%), altitude (2.85%), slope (5.97%), distance from mines (18.05%), roads (2.17%), and settlements (5.18%)) were more sensitive to deforestation. Most of the sensitive parameters showed a positive correlation with DS. The AUC values of the ROC curve had shown a better fit for AHP (0.72) than (0.69) FR and LR (0.68) models for present DS results. The correlation results had shown a good inverse relationship between DS and distance from mines and foliar dust concentration. This work will espouse the future work in the effective planning and management of the mining-affected forest region and predicted deforestation susceptibility would be helpful for forest ecosystem study and policymaking.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Agricultura Florestal , Florestas , Humanos , Índia , Árvores
19.
J Assoc Physicians India ; 69(7): 11-12, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34431275

RESUMO

Traditional communication of medical literature using evidence-based terminologies are inadequate as the body of COVID-19 literature increases thereby requiring alternate methods of communication like podcasts, webinars, social media. A common theme in all these alternate forms of communication is the art of storytelling that allows physicians to make a connection with a patient by understanding their perspectives. Apart from few situations where story telling can be distracting in many situations where the patient's history is complex and require great listening skills and empathy.. Learning to be a good storyteller can help the physician help patients be a great change agent for them. Communicating with these patients can be done effectively using standard communication tools and using effective storytelling techniques can reinforce the patients trust in the provider and strengthen patient physician relationship. This could have a salutatory result both for the patient by increasing patient satisfaction and compliance with treatment and physician satisfaction by increasing to understand their patient's true concerns.


Assuntos
COVID-19 , Médicos , Comunicação , Humanos , Relações Médico-Paciente , SARS-CoV-2
20.
Angew Chem Int Ed Engl ; 60(37): 20558-20562, 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34289211

RESUMO

Reversible switching between the closed cyclic dimeric assembly [Cu2 (1)2 ]2+ (OFF state) and the extended dimeric homoleptic complex [FeCu2 (1)2 ]4+ (ON State) by addition/removal of Fe2+ triggered catalysis of a double-click reaction and high yield preparation of [2]rotaxanes. Mechanistic and computational studies provide valuable general insight for double-click strategies by revealing cooperative effects in the second cycloaddition step due to a distance-tolerant preorganization of the first-click product by the two copper(I)-loaded phenanthroline subunits of [FeCu2 (1)2 ]4+ .

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