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1.
Sci Rep ; 14(1): 14208, 2024 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-38902252

RESUMO

The COVID-19 disease is an ongoing global health concern. Although vaccination provides some protection, people are still susceptible to re-infection. Ostensibly, certain populations or clinical groups may be more vulnerable. Factors causing these differences are unclear and whilst socioeconomic and cultural differences are likely to be important, human genetic factors could influence susceptibility. Experimental studies indicate SARS-CoV-2 uses innate immune suppression as a strategy to speed-up entry and replication into the host cell. Therefore, it is necessary to understand the impact of variants in immunity-associated human proteins on susceptibility to COVID-19. In this work, we analysed missense coding variants in several SARS-CoV-2 proteins and their human protein interactors that could enhance binding affinity to SARS-CoV-2. We curated a dataset of 19 SARS-CoV-2: human protein 3D-complexes, from the experimentally determined structures in the Protein Data Bank and models built using AlphaFold2-multimer, and analysed the impact of missense variants occurring in the protein-protein interface region. We analysed 468 missense variants from human proteins and 212 variants from SARS-CoV-2 proteins and computationally predicted their impacts on binding affinities for the human viral protein complexes. We predicted a total of 26 affinity-enhancing variants from 13 human proteins implicated in increased binding affinity to SARS-CoV-2. These include key-immunity associated genes (TOMM70, ISG15, IFIH1, IFIT2, RPS3, PALS1, NUP98, AXL, ARF6, TRIMM, TRIM25) as well as important spike receptors (KREMEN1, AXL and ACE2). We report both common (e.g., Y13N in IFIH1) and rare variants in these proteins and discuss their likely structural and functional impact, using information on known and predicted functional sites. Potential mechanisms associated with immune suppression implicated by these variants are discussed. Occurrence of certain predicted affinity-enhancing variants should be monitored as they could lead to increased susceptibility and reduced immune response to SARS-CoV-2 infection in individuals/populations carrying them. Our analyses aid in understanding the potential impact of genetic variation in immunity-associated proteins on COVID-19 susceptibility and help guide drug-repurposing strategies.


Assuntos
COVID-19 , Mutação de Sentido Incorreto , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , SARS-CoV-2/imunologia , COVID-19/genética , COVID-19/virologia , COVID-19/imunologia , Reposicionamento de Medicamentos , Proteínas Virais/genética , Proteínas Virais/metabolismo , Ligação Proteica , Predisposição Genética para Doença , Suscetibilidade a Doenças , Tratamento Farmacológico da COVID-19
2.
Front Mol Neurosci ; 17: 1322273, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38486962

RESUMO

The use of predators and predator odor as stressors is an important and ecologically relevant model for studying the impact of behavioral responses to threat. Here we summarize neural substrates and behavioral changes in rats resulting from predator exposure. We briefly define the impact predator exposure has on neural targets throughout development (neonatal, juvenile, and adulthood). These findings allow us to conceptualize the impact of predator exposure in the brain, which in turn may have broader implications for human disorders such as PTSD. Importantly, inclusion of sex as a biological variable yields distinct results that may indicate neural substrates impacted by predator exposure differ based on sex.

3.
J Mol Biol ; : 168551, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38548261

RESUMO

CATH (https://www.cathdb.info) classifies domain structures from experimental protein structures in the PDB and predicted structures in the AlphaFold Database (AFDB). To cope with the scale of the predicted data a new NextFlow workflow (CATH-AlphaFlow), has been developed to classify high-quality domains into CATH superfamilies and identify novel fold groups and superfamilies. CATH-AlphaFlow uses a novel state-of-the-art structure-based domain boundary prediction method (ChainSaw) for identifying domains in multi-domain proteins. We applied CATH-AlphaFlow to process PDB structures not classified in CATH and AFDB structures from 21 model organisms, expanding CATH by over 100%. Domains not classified in existing CATH superfamilies or fold groups were used to seed novel folds, giving 253 new folds from PDB structures (September 2023 release) and 96 from AFDB structures of proteomes of 21 model organisms. Where possible, functional annotations were obtained using (i) predictions from publicly available methods (ii) annotations from structural relatives in AFDB/UniProt50. We also predicted functional sites and highly conserved residues. Some folds are associated with important functions such as photosynthetic acclimation (in flowering plants), iron permease activity (in fungi) and post-natal spermatogenesis (in mice). CATH-AlphaFlow will allow us to identify many more CATH relatives in the AFDB, further characterising the protein structure landscape.

4.
Cureus ; 15(9): e44726, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37809171

RESUMO

Eighty percent of women who have cervical cancer present at such an alarmingly advanced stage leading to high morbidity and mortality. Due to a lack of public awareness and inadequate infrastructure for screening and early identification in resource-poor countries like India, this tardy presentation is anticipated to continue in the future. Standard management for locally advanced squamous cell cervical cancer is radiotherapy. To increase responses and survival, neoadjuvant chemotherapy (NACT) was introduced to the arsenal. Recent studies from India have shown encouraging results for women getting concomitant chemo-radiation for locally advanced cervical cancer. However, toxicities are still a major problem. The approximated five-year actuarial survival rate with NACT is roughly 45% (95% confidence interval, 37-53%) with a median survival rate of 56 months. Compared to radiotherapy alone, patients receiving chemo-radiation are said to have a considerably better survival rate. Vomiting and nausea are the adverse effects that occur most frequently. Renal dysfunction and myelosuppression can also happen. However, there is evidence of effective tumor control. We will talk about a 55-year-old, para 5 elderly lady who had white discharge coming from her vagina and a cervical mass that bled when touched. She underwent NACT for six weekly cycles, followed by definitive chemo-radiation, and she responded favorably to this management strategy, indicating that the addition of chemotherapy is yet another cause for optimism in the management of cancer of the cervix.

5.
J Am Soc Mass Spectrom ; 34(8): 1549-1558, 2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37405781

RESUMO

Traumatic stress triggers or exacerbates multiple psychiatric illnesses, including post-traumatic stress disorder (PTSD). Nevertheless, the neurophysiological mechanisms underlying stress-induced pathology remain unclear, in part due to the limited understanding of neuronal signaling molecules, such as neuropeptides, in this process. Here, we developed mass spectrometry (MS)-based qualitative and quantitative analytical strategies to profile neuropeptides in rats exposed to predator odor (an ethologically relevant analogue of trauma-like stress) versus control subjects (no odor) to determine peptidomic alterations induced by trauma. In total, 628 unique neuropeptides were identified across 5 fear-circuitry-related brain regions. Brain-region-specific changes of several neuropeptide families, including granin, ProSAAS, opioids, cholecystokinin, and tachykinin, were also observed in the stressed group. Neuropeptides from the same protein precursor were found to vary across different brain regions, indicating the site-specific effects of predator stress. This study reveals for the first time the interaction between neuropeptides and traumatic stress, providing insights into the molecular mechanisms of stress-induced psychopathology and suggesting putative novel therapeutic strategies for disorders such as PTSD.


Assuntos
Neuropeptídeos , Transtornos de Estresse Pós-Traumáticos , Ratos , Animais , Transtornos de Estresse Pós-Traumáticos/metabolismo , Transtornos de Estresse Pós-Traumáticos/psicologia , Encéfalo/metabolismo , Neuropeptídeos/metabolismo
6.
Brain Res ; 1809: 148339, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-36966960

RESUMO

DNA topoisomerases are essential for preserving genomic integrity. DNA topoisomerases induce breakage of DNA to facilitate replication and transcription by relaxing DNA and relieving supercoiling. Aberrant expression and deletions of topoisomerases are associated with psychiatric disorders such as schizophrenia and autism. Our study investigated the effects of early life stress (ELS) on three topoisomerases, Top1, Top3α, and Top3ß in the developing rat brain. Newborn rats were exposed to a predator odor stress on postnatal days 1, 2, and 3; brain tissue was collected either 30 min after the last stressor on postnatal day 3 or during the juvenile period. We found that exposure to predator odor resulted in a decrease in Top3ß expression levels in the neonatal male amygdala and in the juvenile prefrontal cortex of males and females. These data suggest that developing males and females respond differently to predator odor-induced stress. As ELS results in lower Top3ß levels, these data suggest that ELS experienced during development may have consequences for genomic structural integrity and increased mental health risk.


Assuntos
DNA Topoisomerases Tipo I , Estresse Psicológico , Animais , Feminino , Masculino , Ratos , Encéfalo/metabolismo , DNA , DNA Topoisomerases/metabolismo , DNA Topoisomerases Tipo I/química , DNA Topoisomerases Tipo I/genética , DNA Topoisomerases Tipo I/metabolismo , Estresse Psicológico/metabolismo
7.
Biomolecules ; 13(2)2023 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-36830646

RESUMO

Protein kinases are important targets for treating human disorders, and they are the second most targeted families after G-protein coupled receptors. Several resources provide classification of kinases into evolutionary families (based on sequence homology); however, very few systematically classify functional families (FunFams) comprising evolutionary relatives that share similar functional properties. We have developed the FunFam-MARC (Multidomain ARchitecture-based Clustering) protocol, which uses multi-domain architectures of protein kinases and specificity-determining residues for functional family classification. FunFam-MARC predicts 2210 kinase functional families (KinFams), which have increased functional coherence, in terms of EC annotations, compared to the widely used KinBase classification. Our protocol provides a comprehensive classification for kinase sequences from >10,000 organisms. We associate human KinFams with diseases and drugs and identify 28 druggable human KinFams, i.e., enriched in clinically approved drugs. Since relatives in the same druggable KinFam tend to be structurally conserved, including the drug-binding site, these KinFams may be valuable for shortlisting therapeutic targets. Information on the human KinFams and associated 3D structures from AlphaFold2 are provided via our CATH FTP website and Zenodo. This gives the domain structure representative of each KinFam together with information on any drug compounds available. For 32% of the KinFams, we provide information on highly conserved residue sites that may be associated with specificity.


Assuntos
Proteínas Quinases , Proteínas , Humanos , Proteínas Quinases/metabolismo , Proteínas/química , Bases de Dados de Proteínas , Homologia de Sequência de Aminoácidos
8.
Commun Biol ; 6(1): 160, 2023 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-36755055

RESUMO

Deep-learning (DL) methods like DeepMind's AlphaFold2 (AF2) have led to substantial improvements in protein structure prediction. We analyse confident AF2 models from 21 model organisms using a new classification protocol (CATH-Assign) which exploits novel DL methods for structural comparison and classification. Of ~370,000 confident models, 92% can be assigned to 3253 superfamilies in our CATH domain superfamily classification. The remaining cluster into 2367 putative novel superfamilies. Detailed manual analysis on 618 of these, having at least one human relative, reveal extremely remote homologies and further unusual features. Only 25 novel superfamilies could be confirmed. Although most models map to existing superfamilies, AF2 domains expand CATH by 67% and increases the number of unique 'global' folds by 36% and will provide valuable insights on structure function relationships. CATH-Assign will harness the huge expansion in structural data provided by DeepMind to rationalise evolutionary changes driving functional divergence.


Assuntos
Furilfuramida , Proteínas , Humanos , Bases de Dados de Proteínas , Proteínas/química
9.
Bioinformatics ; 39(1)2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36648327

RESUMO

MOTIVATION: CATH is a protein domain classification resource that exploits an automated workflow of structure and sequence comparison alongside expert manual curation to construct a hierarchical classification of evolutionary and structural relationships. The aim of this study was to develop algorithms for detecting remote homologues missed by state-of-the-art hidden Markov model (HMM)-based approaches. The method developed (CATHe) combines a neural network with sequence representations obtained from protein language models. It was assessed using a dataset of remote homologues having less than 20% sequence identity to any domain in the training set. RESULTS: The CATHe models trained on 1773 largest and 50 largest CATH superfamilies had an accuracy of 85.6 ± 0.4% and 98.2 ± 0.3%, respectively. As a further test of the power of CATHe to detect more remote homologues missed by HMMs derived from CATH domains, we used a dataset consisting of protein domains that had annotations in Pfam, but not in CATH. By using highly reliable CATHe predictions (expected error rate <0.5%), we were able to provide CATH annotations for 4.62 million Pfam domains. For a subset of these domains from Homo sapiens, we structurally validated 90.86% of the predictions by comparing their corresponding AlphaFold2 structures with structures from the CATH superfamilies to which they were assigned. AVAILABILITY AND IMPLEMENTATION: The code for the developed models is available on https://github.com/vam-sin/CATHe, and the datasets developed in this study can be accessed on https://zenodo.org/record/6327572. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Algoritmos , Proteínas , Humanos , Homologia de Sequência de Aminoácidos , Proteínas/química , Bases de Dados de Proteínas
10.
J Biosoc Sci ; 55(3): 479-494, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-35766169

RESUMO

This study aimed to assess the nature and magnitude of perceptions of wife-beating among women and men in Nepal and experiences of domestic violence (DV) and help-seeking among DV victims. The Nepal Demographic Health Surveys (NDHS) (2001, 2006, 2011, 2016) included questions on whether women and men justify wife-beating and whether DV victims sought help (NDHS 2011 and 2016). Covariates in regression models were guided by the socioecological model. We estimated odds ratios for dichotomous outcomes. Compiled data from Multiple Indicator Cluster Surveys was used to understand trends. About 29.1% women justified wife-beating in 2001, 24.2% in 2006, and 29.1% in 2016. About 32.4% of women experienced any DV in 2011 and 28.0% in 2016. In 2011 about 21.8% of those abused sought help and in 2016 about 25.8% sought help. Women who justified wife-beating were more likely to experience DV in 2011 (OR 5.8, p < 0.001) and in 2016 (OR 1.5, p < 0.001) and less likely to seek help in 2011 (OR 0.3, p < 0.001) and in 2016 (OR 0.8, p < 0.001). Perceptions of wife-beating play an important role in actual experiences of DV and help-seeking behavior of DV victims. Societal and individual beliefs are intertwined, and cultural norms have a great bearing on these beliefs. Both individual and wider societal-level acceptance of violence needs to be addressed simultaneously.


Assuntos
Violência Doméstica , Maus-Tratos Conjugais , Masculino , Humanos , Feminino , Cônjuges , Nepal
11.
Comput Struct Biotechnol J ; 20: 6302-6316, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36408455

RESUMO

Coronavirus disease 2019 (COVID-19) caused by SARS-CoV-2 is an ongoing pandemic that causes significant health/socioeconomic burden. Variants of concern (VOCs) have emerged affecting transmissibility, disease severity and re-infection risk. Studies suggest that the - N-terminal domain (NTD) of the spike protein may have a role in facilitating virus entry via sialic-acid receptor binding. Furthermore, most VOCs include novel NTD variants. Despite global sequence and structure similarity, most sialic-acid binding pockets in NTD vary across coronaviruses. Our work suggests ongoing evolutionary tuning of the sugar-binding pockets and recent analyses have shown that NTD insertions in VOCs tend to lie close to loops. We extended the structural characterisation of these sugar-binding pockets and explored whether variants could enhance sialic acid-binding. We found that recent NTD insertions in VOCs (i.e., Gamma, Delta and Omicron variants) and emerging variants of interest (VOIs) (i.e., Iota, Lambda and Theta variants) frequently lie close to sugar-binding pockets. For some variants, including the recent Omicron VOC, we find increases in predicted sialic acid-binding energy, compared to the original SARS-CoV-2, which may contribute to increased transmission. These binding observations are supported by molecular dynamics simulations (MD). We examined the similarity of NTD across Betacoronaviruses to determine whether the sugar-binding pockets are sufficiently similar to be exploited in drug design. Whilst most pockets are too structurally variable, we detected a previously unknown highly structurally conserved pocket which can be investigated in pursuit of a generic pan-Betacoronavirus drug. Our structure-based analyses help rationalise the effects of VOCs and provide hypotheses for experiments. Our findings suggest a strong need for experimental monitoring of changes in NTD of VOCs.

12.
Methods Mol Biol ; 2449: 43-91, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35507259

RESUMO

Databases of three-dimensional structures of proteins (and their associated molecules) provide: (a) Curated repositories of coordinates of experimentally determined structures, including extensive metadata; for instance information about provenance, details about data collection and interpretation, and validation of results. (b) Information-retrieval tools to allow searching to identify entries of interest and provide access to them. (c) Links among databases, especially to databases of amino-acid and genetic sequences, and of protein function; and links to software for analysis of amino-acid sequence and protein structure, and for structure prediction. (d) Collections of predicted three-dimensional structures of proteins. These will become more and more important after the breakthrough in structure prediction achieved by AlphaFold2. The single global archive of experimentally determined biomacromolecular structures is the Protein Data Bank (PDB). It is managed by wwPDB, a consortium of five partner institutions: the Protein Data Bank in Europe (PDBe), the Research Collaboratory for Structural Bioinformatics (RCSB), the Protein Data Bank Japan (PDBj), the BioMagResBank (BMRB), and the Electron Microscopy Data Bank (EMDB). In addition to jointly managing the PDB repository, the individual wwPDB partners offer many tools for analysis of protein and nucleic acid structures and their complexes, including providing computer-graphic representations. Their collective and individual websites serve as hubs of the community of structural biologists, offering newsletters, reports from Task Forces, training courses, and "helpdesks," as well as links to external software.Many specialized projects are based on the information contained in the PDB. Especially important are SCOP, CATH, and ECOD, which present classifications of protein domains.


Assuntos
Proteínas , Software , Biologia Computacional , Bases de Dados de Proteínas , Conformação Proteica , Proteínas/química
13.
Health Soc Care Community ; 30(1): e113-e125, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-33978287

RESUMO

The Chinese government has been reforming the health care system by developing a primary care system. The objectives of this study were to compare the willingness to use and satisfaction with community health care centres (CHCs), a component within the Chinese primary care system, between locals and migrants living in Luohu, Shenzhen, China. A 2019 cross-sectional survey data that interviewed 1,205 adult residents living in Luohu district were used for secondary data analysis. Two identifications of migrants were used for analysis, Shenzhen hukou status and urban village status. Linear probability models were used to determine relationship between migrants' status and the outcome variable of willingness to use CHCs and order logistic regression were used to determine the association between migrants' status and the outcome variable of satisfaction with CHCs. Among participants, 37.6% of the participants had Shenzhen hukou. Using the classification of urban village status, 29.1% of participants were urban villagers. Urban villagers were less likely to know the location of nearest CHCs and less likely to select CHCs as their frequently used health care institutions. No statistically significant difference was found on willingness to use CHCs or satisfaction with CHCs between Shenzhen hukou and non-Shenzhen hukou. But urban villagers were more satisfied with attitude and medical skills of health care workers. Our findings indicated that policymakers and social professionals need to adjust the organization and functioning of primary care institutions in the community to increase awareness and utilization of primary care services.


Assuntos
Migrantes , Adulto , China , Estudos Transversais , Humanos , Satisfação Pessoal , Atenção Primária à Saúde
14.
Indian J Otolaryngol Head Neck Surg ; 74(Suppl 2): 3173-3177, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34642631

RESUMO

The protection efficacy of face masks during this covid 19 pandemic has been well documented. The changes in human nasal functions after wearing facemask for prolonged period is not known. The aim of this study is to determine the effects of prolonged usage of facemask by ENT professionals during covid 19 pandemic. It is a cross sectional study conducted in department of ENT in Chettinad Hospital and Research Institute, Kelambakkam. A self-constructed questionnaire containing 21 queries regarding the effects of prolonged use of face mask, after being analysed by the experts of our institution were distributed to 124 ENT professionals all over India. People who are ENT by professionals can participate in this study. Participation is voluntary. Study period was from March 2020 to December 2020. All answered questionnaires were sent for statistical analysis. 63.71% experienced difficulty in breathing while wearing face mask, 37.10% experienced dry nose, 46.77% experienced dry mouth. The most common modality of prevention in an OPD setup was face mask with face shield (31.45%). About 80.65% people believed there are side effects due to wearing mask. Since facemasks are essential to protect us from COVID-19, certain strategies can be followed to reduce the discomfort due to its prolonged usage such as encouraging nasal breathing, taking short breaks from wearing mask in a safe environment and to maintain hydration.

15.
Preprint em Inglês | bioRxiv | ID: ppbiorxiv-471394

RESUMO

Coronavirus disease 2019 (COVID-19) caused by SARS-CoV-2 is an ongoing pandemic that causes significant health/socioeconomic burden. Variants of concern (VOCs) have emerged which may affect transmissibility, disease severity and re-infection risk. Most studies focus on the receptor-binding domain (RBD) of the Spike protein. However, some studies suggest that the Spike N-terminal domain (NTD) may have a role in facilitating virus entry via sialic-acid receptor binding. Furthermore, most VOCs include novel NTD variants. Recent analyses demonstrated that NTD insertions in VOCs tend to lie close to loop regions likely to be involved in binding sialic acids. We extended the structural characterisation of these putative sugar binding pockets and explored whether variants could enhance the binding to sialic acids and therefore to the host membrane, thereby contributing to increased transmissibility. We found that recent NTD insertions in VOCs (i.e., Gamma, Delta and Omicron variants) and emerging variants of interest (VOIs) (i.e., Iota, Lambda, Theta variants) frequently lie close to known and putative sugar-binding pockets. For some variants, including the recent Omicron VOC, we find increases in predicted sialic acid binding energy, compared to the original SARS-CoV-2, which may contribute to increased transmission. We examined the similarity of NTD across a range of related Betacoronaviruses to determine whether the putative sugar-binding pockets are sufficiently similar to be exploited in drug design. Despite global sequence and structure similarity, most sialic-acid binding pockets of NTD vary across related coronaviruses. Typically, SARS-CoV-2 possesses additional loops in these pockets that increase contact with polysaccharides. Our work suggests ongoing evolutionary tuning of the sugar-binding pockets in the virus. Whilst three of the pockets are too structurally variable to be amenable to pan Betacoronavirus drug design, we detected a fourth pocket that is highly structurally conserved and could therefore be investigated in pursuit of a generic drug. Our structure-based analyses help rationalise the effects of VOCs and provide hypotheses for experiments. For example, the Omicron variant, which has increased binding to sialic acids in pocket 3, has a rather unique insertion near pocket 3. Our work suggests a strong need for experimental monitoring of VOC changes in NTD.

16.
Curr Opin Struct Biol ; 70: 108-122, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34225010

RESUMO

Understanding the mechanisms of protein function is indispensable for many biological applications, such as protein engineering and drug design. However, experimental annotations are sparse, and therefore, theoretical strategies are needed to fill the gap. Here, we present the latest developments in building functional subclassifications of protein superfamilies and using evolutionary conservation to detect functional determinants, for example, catalytic-, binding- and specificity-determining residues important for delineating the functional families. We also briefly review other features exploited for functional site detection and new machine learning strategies for combining multiple features.


Assuntos
Evolução Biológica , Proteínas , Sítios de Ligação , Catálise , Biologia Computacional , Humanos , Aprendizado de Máquina , Engenharia de Proteínas , Proteínas/genética
17.
J Environ Manage ; 290: 112597, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-33878627

RESUMO

This study was aimed to isolate fast-growing thraustochytrids and the influence of seasonal variation in fatty acid composition from the mangrove habitat. The thraustochytrids were isolated from fallen yellowish or green mangrove leaves, in four seasons, including winter, summer, rainy, and post rainy season in one year. The thraustochytrids were analyzed for biomass production, total lipid content, and fatty acid profile. The thraustochytrid isolates showed biomass yield and total lipid content in the range of 14.12 ± 0.69 to 22.98 ± 0.53 g/L and 34.98-58.86% per dry cell weight, respectively. The isolates showed two dominant fatty acids, palmitic acid (PA) as saturated fatty acid (SFA) and docosahexaenoic acid (DHA) as long-chain polyunsaturated fatty acids (LC-PUFA) in total fatty acid (TFA) content. The significant differences (P < 0.05) were observed for seasonal variations in SFA and DHA content in summer isolates and winter isolates. The maximum DHA content with 47.12% of TFA, recorded in winter (January) isolates and summer (April) isolates with SFA 68.82% of TFA. The results from this study were verified the hypothesis that the presence of high DHA producing thraustochytrids in lower temperature season in the same habitat. These findings have also emphasized the role of the environmental temperature conditions and the importance of thraustochytrid fatty acid composition as a dietary biomarker. Also, it revealed the ecological significance of thraustochytrid in DHA enrichment in the food web of the marine ecosystem. These findings could be useful while isolating thraustochytrids according to seasons for industrial application for omega 3 fatty acids and biodiesel production.


Assuntos
Ácidos Graxos , Estramenópilas , Ecossistema , Índia , Estações do Ano
18.
Sci Rep ; 11(1): 3549, 2021 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-33574362

RESUMO

Early life stress (ELS) has been shown to have a significant impact on typical brain development and the manifestation of psychological disorders through epigenetic modifications that alter gene expression. Line1, a retrotransposon associated with genetic diversity, has been linked with various psychological disorders that are associated with ELS. Our previous work demonstrated altered Line1 DNA copy number in the neonatal period following stressful experiences; we therefore chose to investigate whether early life stress altered Line1 retrotransposition persists into the juvenile period of development. Our study uses a neonatal predator odor exposure (POE) paradigm to model ELS in rats. We examined Line1 using qPCR to assess Line1 expression levels and DNA copy number in the male and female juvenile amygdala, hippocampus and prefrontal cortex-areas chosen for their association with affective disorders and stress. We report a sex difference in Line1 levels within the juvenile amygdala. We also find that ELS significantly increases Line1 DNA copy number within the juvenile amygdala which correlates with reduced juvenile social play levels, suggesting the possibility that Line1 may influence juvenile social development.


Assuntos
Experiências Adversas da Infância , Encéfalo/crescimento & desenvolvimento , Elementos Nucleotídeos Longos e Dispersos/genética , Estresse Psicológico/genética , Tonsila do Cerebelo/crescimento & desenvolvimento , Tonsila do Cerebelo/metabolismo , Tonsila do Cerebelo/patologia , Animais , Encéfalo/patologia , Variações do Número de Cópias de DNA/genética , Modelos Animais de Doenças , Feminino , Hipocampo/metabolismo , Hipocampo/patologia , Humanos , Masculino , Córtex Pré-Frontal/metabolismo , Córtex Pré-Frontal/patologia , Ratos , Caracteres Sexuais , Estresse Psicológico/patologia
19.
Folia Med (Plovdiv) ; 63(4): 557-568, 2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-35851176

RESUMO

Febuxostat is a selective inhibitor of xanthine oxidase and belongs to BCS class II drugs having low solubility and high permeability. Solubility is the most important parameter which directly affects dissolution, absorption and bioavailability of the drugs. There are different techniques by which we can improve solubility and dissolution rate of poorly soluble drug. Amorphous solid dispersion is one of the methods which can improve solubility as well as powder characteristics. The aim of the present study was to formulate and optimize various methods of formulating solid dispersion by using various drug-to-polymer ratios and identifying the batch which gives higher solubility as well as amorphous powder of the drug febuxostat. Different techniques like hot melt method, solvent evaporation method and spray drying techniques were selected for optimization. Attempts were made to improve solubility of febuxostat by employing Kolliphor P 188, Kolliphor P 237, Eudragit RLPO in different drug-to-polymer ratios (1:1, 1:1.5, 1:2) as carrier. The prepared solid dispersion was characterized for the saturation solubility, percentage yield, using differential scanning calorimetry (DSC), scanning electron microscopy (SEM), powdered X-ray diffraction studies (PXRD), and residual solvent determination. Solid state characterization indicated that febuxostat was present in the amorphous form after mixing with polymeric carrier. In contrast to the pure form of drug, solid dispersion of the drug showed better solubility and amorphous characteristics which can be attributed to decreased crystallinity due to hydrotrophy. Thus, amorphous solid dispersion approach can be used successfully to enhance solubility, dissolution rate and bioavailability of febuxostat.


Assuntos
Excipientes , Febuxostat , Disponibilidade Biológica , Polímeros , Pós , Solubilidade , Solventes
20.
Brief Bioinform ; 22(2): 742-768, 2021 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-33348379

RESUMO

SARS-CoV-2 is the causative agent of COVID-19, the ongoing global pandemic. It has posed a worldwide challenge to human health as no effective treatment is currently available to combat the disease. Its severity has led to unprecedented collaborative initiatives for therapeutic solutions against COVID-19. Studies resorting to structure-based drug design for COVID-19 are plethoric and show good promise. Structural biology provides key insights into 3D structures, critical residues/mutations in SARS-CoV-2 proteins, implicated in infectivity, molecular recognition and susceptibility to a broad range of host species. The detailed understanding of viral proteins and their complexes with host receptors and candidate epitope/lead compounds is the key to developing a structure-guided therapeutic design. Since the discovery of SARS-CoV-2, several structures of its proteins have been determined experimentally at an unprecedented speed and deposited in the Protein Data Bank. Further, specialized structural bioinformatics tools and resources have been developed for theoretical models, data on protein dynamics from computer simulations, impact of variants/mutations and molecular therapeutics. Here, we provide an overview of ongoing efforts on developing structural bioinformatics tools and resources for COVID-19 research. We also discuss the impact of these resources and structure-based studies, to understand various aspects of SARS-CoV-2 infection and therapeutic development. These include (i) understanding differences between SARS-CoV-2 and SARS-CoV, leading to increased infectivity of SARS-CoV-2, (ii) deciphering key residues in the SARS-CoV-2 involved in receptor-antibody recognition, (iii) analysis of variants in host proteins that affect host susceptibility to infection and (iv) analyses facilitating structure-based drug and vaccine design against SARS-CoV-2.


Assuntos
Antivirais/uso terapêutico , Tratamento Farmacológico da COVID-19 , Biologia Computacional , SARS-CoV-2/isolamento & purificação , COVID-19/virologia , Humanos , Conformação Proteica , Proteínas Virais/química
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