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1.
PLoS Pathog ; 19(12): e1011844, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38060615

RESUMEN

Virologic suppression with antiretroviral therapy (ART) has significantly improved health outcomes for people living with HIV, yet challenges related to chronic inflammation in the central nervous system (CNS)-known as Neuro-HIV- persist. As primary targets for HIV-1 with the ability to survey and populate the CNS and interact with myeloid cells to co-ordinate neuroinflammation, CD4 T cells are pivotal in Neuro-HIV. Despite their importance, our understanding of CD4 T cell distribution in virus-targeted CNS tissues, their response to infection, and potential recovery following initiation of ART remain limited. To address these gaps, we studied ten SIVmac251-infected rhesus macaques using an ART regimen simulating suboptimal adherence. We evaluated four macaques during the acute phase pre-ART and six during the chronic phase. Our data revealed that HIV target CCR5+ CD4 T cells inhabit both the brain parenchyma and adjacent CNS tissues, encompassing choroid plexus stroma, dura mater, and the skull bone marrow. Aligning with the known susceptibility of CCR5+ CD4 T cells to viral infection and their presence within the CNS, high levels of viral RNA were detected in the brain parenchyma and its border tissues during acute SIV infection. Single-cell RNA sequencing of CD45+ cells from the brain revealed colocalization of viral transcripts within CD4 clusters and significant activation of antiviral molecules and specific effector programs within T cells, indicating CNS CD4 T cell engagement during infection. Acute infection led to marked imbalance in the CNS CD4/CD8 ratio which persisted into the chronic phase. These observations underscore the functional involvement of CD4 T cells within the CNS during SIV infection, enhancing our understanding of their role in establishing CNS viral presence. Our findings offer insights for potential T cell-focused interventions while underscoring the challenges in eradicating HIV from the CNS, particularly in the context of sub-optimal ART.


Asunto(s)
Infecciones por VIH , Síndrome de Inmunodeficiencia Adquirida del Simio , Virus de la Inmunodeficiencia de los Simios , Animales , Humanos , Linfocitos T CD4-Positivos , Virus de la Inmunodeficiencia de los Simios/fisiología , Macaca mulatta , Sistema Nervioso Central , Carga Viral
2.
J Cell Biochem ; 125(3): e30533, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38345373

RESUMEN

Dihydrofolate reductase (DHFR) is a ubiquitous enzyme that regulates the biosynthesis of tetrahydrofolate among various species of Plasmodium parasite. It is a validated target of the antifolate drug pyrimethamine (Pyr) in Plasmodium falciparum (Pf), but its clinical efficacy has been hampered due to the emergence of drug resistance. This has made the attempt to screen Food & Drug Administration-approved drugs against wild- and mutant PfDHFR by employing an in-silico pipeline to identify potent candidates. The current study has followed a virtual screening approach for identifying potential DHFR inhibitors from DrugBank database, based on a structure similarity search of candidates, followed by absorption, distribution, metabolism, and excretion estimation. The screened drugs were subjected to various parameters like docking, molecular mechanics with generalized born and surface area solvation calculations, and molecular simulations. We have thus identified two potential drug candidates, duloxetine and guanethidine, which can be repurposed to be tested for their efficacy against wild type and drug resistant falciparum malaria.


Asunto(s)
Antimaláricos , Antagonistas del Ácido Fólico , Malaria , Humanos , Antimaláricos/farmacología , Antimaláricos/química , Tetrahidrofolato Deshidrogenasa/genética , Tetrahidrofolato Deshidrogenasa/química , Tetrahidrofolato Deshidrogenasa/metabolismo , Preparaciones Farmacéuticas , Reposicionamiento de Medicamentos , Malaria/tratamiento farmacológico , Antagonistas del Ácido Fólico/farmacología , Antagonistas del Ácido Fólico/química , Resistencia a Medicamentos , Ácido Fólico
3.
PLoS Pathog ; 18(4): e1009925, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35443018

RESUMEN

Early in the SARS-CoV-2 pandemic, there was a high level of optimism based on observational studies and small controlled trials that treating hospitalized patients with convalescent plasma from COVID-19 survivors (CCP) would be an important immunotherapy. However, as more data from controlled trials became available, the results became disappointing, with at best moderate evidence of efficacy when CCP with high titers of neutralizing antibodies was used early in infection. To better understand the potential therapeutic efficacy of CCP, and to further validate SARS-CoV-2 infection of macaques as a reliable animal model for testing such strategies, we inoculated 12 adult rhesus macaques with SARS-CoV-2 by intratracheal and intranasal routes. One day later, 8 animals were infused with pooled human CCP with a high titer of neutralizing antibodies (RVPN NT50 value of 3,003), while 4 control animals received normal human plasma. Animals were monitored for 7 days. Animals treated with CCP had detectable but low levels of antiviral antibodies after infusion. In comparison to the control animals, CCP-treated animals had similar levels of viral RNA in upper and lower respiratory tract secretions, similar detection of viral RNA in lung tissues by in situ hybridization, but lower amounts of infectious virus in the lungs. CCP-treated animals had a moderate, but statistically significant reduction in interstitial pneumonia, as measured by comprehensive lung histology. Thus overall, therapeutic benefits of CCP were marginal and inferior to results obtained earlier with monoclonal antibodies in this animal model. By highlighting strengths and weaknesses, data of this study can help to further optimize nonhuman primate models to provide proof-of-concept of intervention strategies, and guide the future use of convalescent plasma against SARS-CoV-2 and potentially other newly emerging respiratory viruses.


Asunto(s)
COVID-19 , SARS-CoV-2 , Animales , Anticuerpos Neutralizantes , Antivirales , COVID-19/terapia , Humanos , Inmunización Pasiva , Macaca mulatta , ARN Viral , Sueroterapia para COVID-19
4.
Dig Dis Sci ; 69(10): 3650-3660, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38816597

RESUMEN

BACKGROUND: Facebook (FB) is the most popular online networking platform. Many celiac disease Facebook (CD-FB) pages spread awareness about celiac disease (CD). To get the latest information, patients with CD frequently follow such pages. However, little is known about whether such pages provide authentic and reliable information. AIMS: This study aims to investigate whether CD-FB pages spread misleading information to patients with CD. METHODS: On the Facebook social networking platform, CD-FB pages created in three celiac-prevalent countries (Italy, the USA, and India) were explored using different combinations of keywords. The type/category of the CD-FB page, country of origin, purpose, page web link, and number of followers/members were documented in a Microsoft spreadsheet. All posts distributed on selected CD-FB pages in the last 3 years were thoroughly screened. RESULTS: From August 2022 to March 2023, a total of 200 CD-FB pages from Italy, the USA, and India were explored. Out of these 200 pages, 155 CD-FB (Italy 70; the USA 46; India 39) were found eligible. Of them, 20 (13%) CD-FB pages (Italy 4; the USA 5; India 11) shared misleading information about CD. Surprisingly, 11 (8%) of these 20 pages (Italy 0; the USA 2; India 9) supported alternative treatment options for CD. CONCLUSIONS: CD-FB pages are useful for disseminating celiac-disease-related information. While most such pages provide useful information, 13% of CD-FB pages allow misleading information. Patients with CD should consult their treating unit before following any uncertain information posted on CD-FB pages.


Asunto(s)
Enfermedad Celíaca , Enfermedad Celíaca/terapia , Enfermedad Celíaca/diagnóstico , Humanos , India/epidemiología , Italia/epidemiología , Estados Unidos/epidemiología , Medios de Comunicación Sociales , Red Social , Educación del Paciente como Asunto
5.
Biodegradation ; 35(2): 117-135, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37684525

RESUMEN

Industrial development and the associated generation of waste requires attention for their management, treatment, and reduction without further degrading the quality of life. Microbes and plant-based bioremediation approaches are some of the sustainable strategies for the biodegradation of harmful pollutants instead of chemical-based treatment. Bioaugmentation is one such approach where microbial strains with the ability to degrade the targeted pollutant are introduced in a polluted environment. Harnessing of microbes from various locations, especially from the site of contamination (indigenous microbes), followed by optimization of the strains, inoculum size, media, and genetic engineering of the microbes along with a combination of strategies such as bio stimulation, phytoremediation is being applied to increase the efficiency of bioaugmentation. Further, bioaugmentation is influenced by various factors such as temperature, the composition of the pollutant, and microbial inoculum which needs to be considered for maximum efficiency of the treatment process. It has numerous advantages such as low cost, sustainability, and easy handling of the contaminants however, the major limitation of bioaugmentation is to increase the survival rate of the microbes involved in remediation for a longer duration in such a highly toxic environment. The review discusses these various aspects of bioaugmentation in brief for its large-scale implementation to address the global issue of pollution and environment management.


Asunto(s)
Contaminantes Ambientales , Contaminantes del Suelo , Calidad de Vida , Biodegradación Ambiental , Contaminantes del Suelo/metabolismo
6.
J Vector Borne Dis ; 61(1): 117-122, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38648413

RESUMEN

BACKGROUND OBJECTIVES: This study reports observation on circulating serotypes and genotypes of Dengue Virus in North India. METHODS: Serum samples were obtained from suspected cases of dengue referred to the virus diagnostic laboratory during 2014 to 2022. All samples were tested for anti-dengue virus IgM antibodies and NS1Ag by ELISA. NS1Ag positive samples were processed for serotyping and genotyping. RESULTS: Total 41,476 dengue suspected cases were referred to the laboratory of which 12,292 (29.6%) tested positive. Anti-Dengue Virus IgM antibodies, NS1Ag, both IgM and NS1Ag, were positive in 7007 (57.4%); 3200 (26.0%) and 2085 (16.0%) cases respectively. Total 762 strains were serotyped during 9-year period. DENV-1, DENV-2, DENV-3 and DENV-4 serotypes were found in 79 (10.37%), 506 (66.40%), 151 (19.82%) and 26 (3.41%) cases respectively. DENV-1, DENV-2 and DENV-3 were in circulation throughout. Total 105 strains were genotyped. Genotype IV of DENV-1 serotype was circulating till 2014 which was later replaced by genotype V. A distinct seasonality with increase in number of cases in post-monsoon period was seen. INTERPRETATION CONCLUSION: DENV-1, DENV-2 and DENV-3 were found to be in circulation in North India. Predominant serotype/genotype changed at times, but not at regular intervals.


Asunto(s)
Anticuerpos Antivirales , Virus del Dengue , Dengue , Genotipo , Serogrupo , India/epidemiología , Virus del Dengue/genética , Virus del Dengue/clasificación , Virus del Dengue/aislamiento & purificación , Humanos , Dengue/virología , Dengue/epidemiología , Dengue/sangre , Anticuerpos Antivirales/sangre , Inmunoglobulina M/sangre , Femenino , Serotipificación , Masculino , Adulto , Niño , Ensayo de Inmunoadsorción Enzimática , Adolescente , Persona de Mediana Edad , Adulto Joven , Estaciones del Año , Preescolar
7.
J Infect Dis ; 2023 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-38041852

RESUMEN

BACKGROUND: Antimalarial drug resistance surveillance and containment are crucial for countries aiming to eliminate malaria. Monitoring resistance evolution through studies before and after treatment policy changes is crucial. METHOD: A total of 939 P. falciparum-positive blood samples were collected between 2014 and 2015 across ten sites in India, categorized into four geographic clusters. PCR-amplified products were sequenced to identify point mutations at drug-resistance-conferring genes (Pfdhfr, Pfdhps, Pfmdr1, Pfk13). RESULT: Triple Pfdhfr mutants were found only in northeast India bordering Myanmar, while the wildtype was dominant in central India. Pfdhps wildtypes were prevalent in all areas, and no double mutants were found. Except in Northwest India, Pfmdr1 wildtype was dominant in all clusters. Nonsynonymous double mutations were only found in northwest India. Only synonymous mutations occurred in Pfk13. These were found in Central India at low frequency. The pattern of linkage disequilibrium and principal component analysis reflects low pressure for drug resistance and heterogeneity between the geographic clusters. CONCLUSION: Resistance levels were highest in Northeast India, close to the Myanmar border, where resistance is common. Primaquine has been widely used as a gametocidal and schizonticidal drug, has likely contributed to maintaining low drug resistance levels and preventing strong selection for resistance.

8.
Eur J Immunol ; 52(4): 618-632, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35108401

RESUMEN

The nonpolymorphic class Ib molecule, HLA-E, primarily presents peptides from HLA class Ia leader peptides, providing an inhibitory signal to NK cells via CD94/NKG2 interactions. Although peptides of pathogenic origin can also be presented by HLA-E to T cells, the molecular basis underpinning their role in antigen surveillance is largely unknown. Here, we solved a co-complex crystal structure of a TCR with an HLA-E presented peptide (pHLA-E) from bacterial (Mycobacterium tuberculosis) origin, and the first TCR-pHLA-E complex with a noncanonically presented peptide from viral (HIV) origin. The structures provided a molecular foundation to develop a novel method to introduce cysteine traps using non-natural amino acid chemistry that stabilized pHLA-E complexes while maintaining native interface contacts between the TCRs and different pHLA-E complexes. These pHLA-E monomers could be used to isolate pHLA-E-specific T cells, with obvious utility for studying pHLA-E restricted T cells, and for the identification of putative therapeutic TCRs.


Asunto(s)
Aminoácidos , Antígenos HLA , Antígenos de Histocompatibilidad Clase I , Péptidos , Receptores de Antígenos de Linfocitos T , Antígenos HLA-E
9.
PLoS Pathog ; 17(7): e1009688, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34228761

RESUMEN

There is an urgent need for effective therapeutic interventions against SARS-CoV-2, including new variants that continue to arise. Neutralizing monoclonal antibodies have shown promise in clinical studies. We investigated the therapeutic efficacy of a combination of two potent monoclonal antibodies, C135-LS and C144-LS that carry half-life extension mutations, in the rhesus macaque model of COVID-19. Twelve young adult macaques (three groups of four animals) were inoculated intranasally and intra-tracheally with a high dose of SARS-CoV-2 and 24 hours later, treated intravenously with a high (40 mg/kg) or low (12 mg/kg) dose of the C135-LS and C144-LS antibody combination, or a control monoclonal antibody. Animals were monitored for 7 days. Compared to the control animals, animals treated with either dose of the anti-SARS-CoV-2 antibodies showed similarly improved clinical scores, lower levels of virus replication in upper and lower respiratory tract, and significantly reduced interstitial pneumonia, as measured by comprehensive lung histology. In conclusion, this study provides proof-of-concept in support of further clinical development of these monoclonal antibodies against COVID-19 during early infection.


Asunto(s)
Anticuerpos Neutralizantes/uso terapéutico , Anticuerpos Antivirales/uso terapéutico , COVID-19/terapia , Pulmón/patología , SARS-CoV-2/inmunología , Replicación Viral , Animales , Anticuerpos Monoclonales/sangre , Anticuerpos Monoclonales/inmunología , Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Neutralizantes/sangre , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/inmunología , COVID-19/patología , COVID-19/virología , Modelos Animales de Enfermedad , Femenino , Pulmón/diagnóstico por imagen , Macaca mulatta , Masculino , Análisis Multivariante , Radiografía , Sistema Respiratorio/virología , SARS-CoV-2/fisiología , Factores de Tiempo , Resultado del Tratamiento , Replicación Viral/inmunología
10.
Crit Rev Food Sci Nutr ; 63(1): 18-32, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-34184959

RESUMEN

Celiac disease (CD) is triggered by both genetic and environmental factors. More than 1% of the world's population is affected by CD. In recent years, studies have confirmed a worldwide rising trend in CD prevalence. "Westernized diet" is one of the main factors of this increasing prevalence. However, the relationship between wheat consumption, its dynamics, and CD has not been adequately investigated on a global scale. This study aimed to perform a multilevel analysis of the association between wheat consumption and CD. Wheat consumption data from countries and continents were obtained from the database. The relative increase/decrease in wheat consumption over a long period (since 1961) and a short period (since 2004) were calculated using various statistical tools. The relationship between wheat consumption and celiac frequency was determined using the R-commander R package version 2.6-2. Pearson's correlation coefficient (r = 0.88) confirmed a high positive correlation between wheat consumption and the prevalence of biopsy-proven CD by estimating continent-wide wheat consumption data, but an insignificant correlation was found when the data were compared country-wide.


Asunto(s)
Enfermedad Celíaca , Humanos , Enfermedad Celíaca/epidemiología , Triticum , Prevalencia , Análisis Multinivel , Dieta
11.
BMC Gastroenterol ; 23(1): 15, 2023 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-36647022

RESUMEN

BACKGROUND AND AIMS: Individuals with celiac disease (CD), non-celiac wheat sensitivity (NCWS), and irritable bowel syndrome (IBS), show overlapping clinical symptoms and experience gut dysbiosis. A limited number of studies so far compared the gut microbiota among these intestinal conditions. This study aimed to investigate the similarities in the gut microbiota among patients with CD, NCWS, and IBS in comparison to healthy controls (HC). MATERIALS AND METHODS: In this prospective study, in total 72 adult subjects, including CD (n = 15), NCWS (n = 12), IBS (n = 30), and HC (n = 15) were recruited. Fecal samples were collected from each individual. A quantitative real-time PCR (qPCR) test using 16S ribosomal RNA was conducted on stool samples to assess the relative abundance of Firmicutes, Bacteroidetes, Bifidobacterium spp., and Lactobacillus spp. RESULTS: In all groups, Firmicutes and Lactobacillus spp. had the highest and lowest relative abundance respectively. The phylum Firmicutes had a higher relative abundance in CD patients than other groups. On the other hand, the phylum Bacteroidetes had the highest relative abundance among healthy subjects but the lowest in patients with NCWS. The relative abundance of Bifidobacterium spp. was lower in subjects with CD (P = 0.035) and IBS (P = 0.001) compared to the HCs. Also, the alteration of Firmicutes to Bacteroidetes ratio (F/B ratio) was statistically significant in NCWS and CD patients compared to the HCs (P = 0.05). CONCLUSION: The principal coordinate analysis (PCoA), as a powerful multivariate analysis, suggested that the investigated gut microbial profile of patients with IBS and NCWS share more similarities to the HCs. In contrast, patients with CD had the most dissimilarity compared to the other groups in the context of the studied gut microbiota.


Asunto(s)
Enfermedad Celíaca , Microbioma Gastrointestinal , Síndrome del Colon Irritable , Hipersensibilidad al Trigo , Adulto , Humanos , Síndrome del Colon Irritable/microbiología , Enfermedad Celíaca/diagnóstico , Microbioma Gastrointestinal/genética , Irán , Estudios Prospectivos , Firmicutes , Bacteroidetes , Heces/microbiología
12.
Parasitol Res ; 122(1): 285-298, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36399171

RESUMEN

During amoebiasis, colonization of the gut by Entamoeba histolytica can lead to alterations of the host microbiota. In this study, we have compared the gut microbiota of patients of amoebiasis with healthy controls using 16S rRNA gene variable regions, (V1-V3) and (V3-V5), of the bacterial genome. From this 16S rRNA gene amplicon data, one paired-end and two single-end datasets were selected and compared by the number of OTUs obtained, sequence count, and diversity analysis. Our results showed that the V1-V3-paired-end dataset gave the maximum number of OTUs in comparison to the two single-end datasets studied. The amoebiasis samples showed a significant drop in richness in the alpha diversity measurements and lower intra group similarity compared to the healthy controls. Bacteria of genus Prevotella, Sutterella, and Collinsella were more abundant in healthy controls whereas Escherichia, Klebsiella, and Ruminococcus were more abundant in the E. histolytica-positive patients. All the healthy controls harbored bacteria belonging to Faecalibacterium, Prevotella, Ruminococcus, Subdoligranulum, and Escherichia genera while all the E. histolytica-positive patient samples contained genus Enterobacter. The compositional changes in the gut microbiome observed in our study indicated a higher prevalence of pathogenic bacteria along with a depletion of beneficial bacteria in E. histolytica-infected individuals when compared with healthy controls. These results underline the interplay between E. histolytica and the human gut microbiome, giving important inputs for future studies and treatments.


Asunto(s)
Entamebiasis , Microbioma Gastrointestinal , Humanos , Microbioma Gastrointestinal/genética , ARN Ribosómico 16S/genética , Bacterias/genética , Diarrea , India , Heces/microbiología
13.
Arch Microbiol ; 204(11): 666, 2022 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-36214917

RESUMEN

Chemical fertilizers and pesticides are an integral part of modern agriculture and are often associated with numerous environmental problems. Biological agents such as microorganisms can largely replace chemical fertilizers and pesticides. The proper use of selected microorganisms such as bacteria, fungi and viruses have several benefits for agriculture. These include a healthy soil microbiota, biological production of important compounds that promote plant health, and to be used as biocontrol agents (BCAs) that provide protection from plant pathogenic microorganisms. Scientists have found that several bacterial genera including Bacillus and Pseudomonas have antimicrobial activity against numerous pathogenic bacterial and fungal plant pathogens. Trichoderma, Aspergillus, and Penicillium are among the most common fungal genera used as BCAs against both bacterial and fungal plant pathogens. Several bacteriophages and mycoviruses are also found effective as BCAs against selective plant pathogens. Fusarium oxysporum is a commonly found microbial plant pathogen causing wilts and rots in plants. Overall, it can be concluded that the use of microbial BCAs is an effective practice against microbial plant pathogens.


Asunto(s)
Antiinfecciosos , Plaguicidas , Bacterias , Factores Biológicos , Fertilizantes , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/prevención & control , Plantas/microbiología , Suelo
14.
Curr Microbiol ; 79(5): 129, 2022 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-35286507

RESUMEN

The pathogenesis of celiac disease (CD) is significantly influenced by gut microbiota. Daily nutritional profile influences the diversity of gut microbiota. This study was aimed to compare the abundance of gut microbiota in CD patients compared to normal control (NC), and to investigate the impact of nutritional factors on their fecal microbiota diversity. In this study, a selected panel of intestinal bacteria was assessed in 31 confirmed CD patients adhering to gluten-free diet (GFD) for more than 6 months and in 20 NC subjects. Stool samples were collected from each participant, DNA was extracted, and absolute quantitative real-time PCR (qPCR) was carried out. The gut microbiota including Bacteroidetes, Bifidobacterium, Clostridium, Staphylococcus, Enterobacteiaceae, Firmicutes, and Lactobacillus were assessed. The quantities of fruits, vegetables, meat, liquids, sugar and gluten-free candy/bread consumption were evaluated using a questionnaire. The proportion of Bifidobacterium, Firmicutes, and Lactobacillus in CD cases was significantly lower than NC (P < 0.005). Significant correlation coefficients between Bifidobacterium and Lactobacillus (P < 0.001), and also Firmicutes and Lactobacillus (P < 0.001) were recorded. Moreover, a significant association between medium amount of meat and bean consumptions and low abundance of Lactobacillus and Firmicutes (P = 0.024 and P = 0.027, respectively), and also high amount of bean consumptions and low abundance of Lactobacillus (P = 0.027) in CD were observed. The results showed that meat and bean consumptions could reduce the beneficial bacteria including Firmicutes and Lactobacillus in CD patients. Therefore, changes in the gut microbiota abundance may contribute to dietary changes and unimproved CD symptoms.


Asunto(s)
Enfermedad Celíaca , Microbioma Gastrointestinal , Microbiota , Bifidobacterium/genética , Heces/microbiología , Humanos
15.
J Environ Sci Health B ; 57(5): 379-420, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35403565

RESUMEN

In the present study, twenty-two derivatives of dihydropyridine (DHP) have been synthesized using the Boric acid catalyst in solventless conditions. The synthesis was confirmed by FTIR analysis, 1HNMR, and 13CNMR analysis. The quantitative structure-activity relationship for all the synthesized derivatives was performed using an artificial neural network with correlation coefficient (R2) 0.8611, mean standard error 0.19, and Comparative molecular field analysis (CoMFA) with correlation coefficient (R2) 0.713, mean standard error 0.27. The molecular docking activity of synthesized compounds was tested using "AUTODOCK VINA" against "Acetohydroxyacid synthase protein receptors (PDB code 1YHZ)" acquired from the "RCSB Protein Data Bank". Docking experiments demonstrated favorable interaction among synthesized DHP derivatives and protein receptors with significant binding energy values. These synthesized derivatives have been screened for their pre-emergence herbicidal bioassay against weed species Echinochola crus galli, and the IC50 value were calculated and activity was compared with Butachlor, significant activity was exhibited by all the derivatives. All the synthesized compounds were also screened for their post emergence herbicidal activity against Echinochola crus galli, and the activity of DHPs were compared with penoxulum. All the synthesized compounds show good to moderate activity. Thus, it is concluded that substituted DHP derivatives may be developed as potential herbicides.


Asunto(s)
Herbicidas , Herbicidas/química , Herbicidas/farmacología , Simulación del Acoplamiento Molecular , Estructura Molecular , Relación Estructura-Actividad Cuantitativa , Relación Estructura-Actividad
16.
Environ Monit Assess ; 195(1): 152, 2022 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-36435881

RESUMEN

Understanding the spread intensity and population dynamics of invasive plant species is a prerequisite for developing management strategies in the Himalayan Forest ecosystems that are experiencing an accelerated rate of climate change. Although there are studies on the occurrence of few invasive species in the Himalayan ecosystems, systematic information on their intensity of spread and species association is still missing. Considering existing data gaps, we aimed to assess the intensity of spread and distribution pattern of A. adenophora, one of the high-concern invasive species (HiCIS) of India that is causing havoc in the Himalayas, across an elevational gradient. Field data were collected in 2018 and 2021 in the Indian federal state of Sikkim, located in the Eastern Himalayas. We analyzed the population status and species association of A. adenophora along an elevational gradient ranging from > 600 m to 2700 m above sea level, which was divided into seven gradients of 300 m width, and each gradient was further randomly sampled. Overall, 81 species were present in association with A. adenophora, including 58 herbs, 19 shrubs, and 4 climbers, belonging to 30 families and 67 genera in the region. No other species continuously co-occurred along with A. adenophora throughout the elevation ranging from > 600 m to 2700 m. The species observed increased frequency (100%), density (40.51 ind./100 m2), and basal cover (11.25 cm2/m2) in the elevational gradient 1500-1800 m in 2018. In 2021, A. adenophora dominated the highest elevational gradient (< 2400-2700 m) with increased frequency (99.96%), density (58.41 ind./100m2), and basal cover (42.54 cm2/100m2), which demonstrated rapid invasion and improved plant health and reproductive vigor in comparison to the lower elevational gradient in Sikkim Himalaya. Despite being completely absent at the highest elevation (< 2400-2700 m), in 2018, it observed gregarious spread at the highest elevation in 2021, which is of serious concern to ecologists. The presence of the targeted species in all seven studied altitudinal gradients reflects stage III of the species invasion. An enormous shift in the distribution pattern along elevational gradients within a short time span is alarming for the Himalayan ecosystem since it is becoming a thriving habitat for invasive species owing to anthropogenic activity. We mapped the potential geographical extent using the species distribution model (SDM) and predicted the suitable habitat of distribution in Sikkim Himalaya. In order to curtail the spread and counteract the negative impact of this species on native vegetation in Sikkim Himalaya and ultimately reverse the process, local and regional initiatives for its biological control and management must be taken.


Asunto(s)
Ageratina , Ecosistema , Humanos , Biodiversidad , Sikkim , Altitud , Monitoreo del Ambiente , Especies Introducidas , India , Plantas
17.
J Cell Biochem ; 122(10): 1326-1336, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33998049

RESUMEN

The emergence and spread of drug resistance in Plasmodium falciparum, the parasite causing the most severe form of human malaria, is a major threat to malaria control and elimination programs around the globe. With P. falciparum having evolved widespread resistance against a number of previously widely used drugs, currently, artemisinin (ART) and its derivatives are the cornerstones of first-line treatments of uncomplicated malaria. However, growing incidences of ART failure reflect the spread of ART-resistant P. falciparum strains. Despite current efforts to understand the primary cause of ART resistance due to mutations in the Kelch 13 gene (PfK13), the mechanism underlying ART resistance is still not completely unclear and no feasible strategies to counteract the causes and thereby restoring the efficiency of ART have been developed. We use a polypharmacology approach to identify potential drugs that can be used for the novel purpose (target). Of note, we have designed a multimodal stratagem to identify approved drugs with a potential antimalarial activity using computational drug reprofiling. Our investigations suggest that oxetacaine, simvastatin, repaglinide, aclidinium, propafenone, and lovastatin could be repurposed for malaria control and prevention.


Asunto(s)
Antimaláricos/farmacología , Artemisininas/farmacología , Reposicionamiento de Medicamentos/métodos , Malaria Falciparum/tratamiento farmacológico , Fosfatidilinositol 3-Quinasa/química , Plasmodium falciparum/efectos de los fármacos , Proteínas Protozoarias/antagonistas & inhibidores , Desarrollo de Medicamentos/métodos , Resistencia a Medicamentos , Ensayos Analíticos de Alto Rendimiento , Humanos , Malaria Falciparum/parasitología , Malaria Falciparum/patología , Fosfatidilinositol 3-Quinasa/metabolismo , Plasmodium falciparum/aislamiento & purificación , Plasmodium falciparum/patogenicidad
18.
J Virol ; 94(6)2020 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-31827000

RESUMEN

Generating durable humoral immunity through vaccination depends upon effective interactions of follicular helper T (Tfh) cells with germinal center (GC) B cells. Th1 polarization of Tfh cells is an important process shaping the success of Tfh-GC B cell interactions by influencing costimulatory and cytokine-dependent Tfh help to B cells. However, the question remains as to whether adjuvant-dependent modulation of Tfh cells enhances HIV-1 vaccine-induced antienvelope (anti-Env) antibody responses. We investigated whether an HIV-1 vaccine platform designed to increase the number of Th1-polarized Tfh cells enhances the magnitude and quality of anti-Env antibodies. Utilizing a novel interferon-induced protein 10 (IP-10)-adjuvanted HIV-1 DNA prime followed by a monophosphoryl lipid A and QS-21 (MPLA+QS-21)-adjuvanted Env protein boost (DIP-10 PALFQ) in macaques, we observed higher anti-Env serum IgG titers with greater cross-clade reactivity, specificity for V1V2, and effector functions than in macaques primed with DNA lacking IP-10 and boosted with MPLA-plus-alum-adjuvanted Env protein (DPALFA) The DIP-10 PALFQ vaccine regimen elicited higher anti-Env IgG1 and lower IgG4 antibody levels in serum, showing for the first time that adjuvants can dramatically impact the IgG subclass profile in macaques. The DIP-10 PALFQ regimen also increased vaginal and rectal IgA antibodies to a greater extent. Within lymph nodes, we observed augmented GC B cell responses and the promotion of Th1 gene expression profiles in GC Tfh cells. The frequency of GC Tfh cells correlated with both the magnitude and avidity of anti-Env serum IgG. Together, these data suggest that adjuvant-induced stimulation of Th1-Tfh cells is an effective strategy for enhancing the magnitude and quality of anti-Env antibody responses.IMPORTANCE The results of the RV144 trial demonstrated that vaccination could prevent HIV transmission in humans and that longevity of anti-Env antibodies may be key to this protection. Efforts to improve upon the prime-boost vaccine regimen used in RV144 have indicated that booster immunizations can increase serum anti-Env antibody titers but only transiently. Poor antibody durability hampers efforts to develop an effective HIV-1 vaccine. This study was designed to identify the specific elements involved in the immunological mechanism necessary to produce robust HIV-1-specific antibodies in rhesus macaques. By clearly defining immune-mediated pathways that improve the magnitude and functionality of the anti-HIV-1 antibody response, we will have the foundation necessary for the rational development of an HIV-1 vaccine.


Asunto(s)
Vacunas contra el SIDA/farmacología , Anticuerpos Anti-VIH/inmunología , VIH-1/inmunología , Inmunización Secundaria , Inmunoglobulina G/inmunología , Células TH1/inmunología , Vacunas contra el SIDA/inmunología , Adyuvantes Inmunológicos/farmacología , Animales , Linfocitos B/inmunología , Linfocitos B/patología , Femenino , Centro Germinal/inmunología , Centro Germinal/patología , Humanos , Lípido A/análogos & derivados , Lípido A/farmacología , Macaca mulatta , Saponinas/farmacología , Células TH1/patología
19.
Hepatology ; 72(5): 1528-1540, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32770836

RESUMEN

BACKGROUND AND AIMS: Therapies for chronic hepatitis B virus (HBV) infection are urgently needed because of viral integration, persistence of viral antigen expression, inadequate HBV-specific immune responses, and treatment regimens that require lifelong adherence to suppress the virus. Immune mobilizing monoclonal T Cell receptors against virus (ImmTAV) molecules represent a therapeutic strategy combining an affinity-enhanced T Cell receptor with an anti-CD3 T Cell-activating moiety. This bispecific fusion protein redirects T cells to specifically lyse infected cells expressing the target virus-derived peptides presented by human leukocyte antigen (HLA). APPROACH AND RESULTS: ImmTAV molecules specific for HLA-A*02:01-restricted epitopes from HBV envelope, polymerase, and core antigens were engineered. The ability of ImmTAV-Env to activate and redirect polyclonal T cells toward cells containing integrated HBV and cells infected with HBV was assessed using cytokine secretion assays and imaging-based killing assays. Elimination of infected cells was further quantified using a modified fluorescent hybridization of viral RNA assay. Here, we demonstrate that picomolar concentrations of ImmTAV-Env can redirect T cells from healthy and HBV-infected donors toward hepatocellular carcinoma (HCC) cells containing integrated HBV DNA resulting in cytokine release, which could be suppressed by the addition of a corticosteroid in vitro. Importantly, ImmTAV-Env redirection of T cells induced cytolysis of antigen-positive HCC cells and cells infected with HBV in vitro, causing a reduction of hepatitis B e antigen and specific loss of cells expressing viral RNA. CONCLUSIONS: The ImmTAV platform has the potential to enable the elimination of infected cells by redirecting endogenous non-HBV-specific T cells, bypassing exhausted HBV-specific T cells. This represents a promising therapeutic option in the treatment of chronic hepatitis B, with our lead candidate now entering trials.


Asunto(s)
Virus de la Hepatitis B/inmunología , Hepatitis B Crónica/tratamiento farmacológico , Receptores de Antígenos de Linfocitos T/uso terapéutico , Proteínas Recombinantes de Fusión/farmacología , Linfocitos T/efectos de los fármacos , Anticuerpos Monoclonales/genética , Anticuerpos Monoclonales/inmunología , Anticuerpos Monoclonales/farmacología , Anticuerpos Monoclonales/uso terapéutico , Complejo CD3/antagonistas & inhibidores , Línea Celular Tumoral , Epítopos/inmunología , Antígeno HLA-A2/inmunología , Antígenos de Superficie de la Hepatitis B/inmunología , Virus de la Hepatitis B/aislamiento & purificación , Hepatitis B Crónica/inmunología , Hepatitis B Crónica/virología , Hepatocitos , Humanos , Inmunoconjugados/genética , Inmunoconjugados/inmunología , Inmunoconjugados/farmacología , Inmunoconjugados/uso terapéutico , Activación de Linfocitos/efectos de los fármacos , Cultivo Primario de Células , Receptores de Antígenos de Linfocitos T/genética , Receptores de Antígenos de Linfocitos T/inmunología , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/inmunología , Proteínas Recombinantes de Fusión/uso terapéutico , Linfocitos T/inmunología
20.
Malar J ; 20(1): 229, 2021 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-34020652

RESUMEN

BACKGROUND: Malaria is a major public health problem in India and accounts for about 88% of malaria burden in South-East Asia. India alone accounted for 2% of total malaria cases globally. Anti-malarial drug resistance is one of the major problems for malaria control and elimination programme. Artemether-lumefantrine (AL) is the first-line treatment of uncomplicated Plasmodium falciparum in north eastern states of India since 2013 after confirming the resistance against sulfadoxine-pyrimethamine. In the present study, therapeutic efficacy of artemether-lumefantrine and k13 polymorphism was assessed in uncomplicated P. falciparum malaria. METHODS: This study was conducted at four community health centres located in Koraput district of Odisha, Bastar district of Chhattisgarh, Balaghat district of Madhya Pradesh and Gondia district of Maharashtra state. Patients with uncomplicated P. falciparum malaria were administered with fixed dose combination (6 doses) of artemether-lumefantrine for 3 days and clinical and parasitological response was recorded up to 28 days as per World Health Organization protocol. Nucleotide sequencing of msp1 and msp2 gene was performed to differentiate between recrudescence and reinfection. Amplification and sequencing of k13 propeller gene region covering codon 450-680 was also carried out to identify the polymorphism. RESULTS: A total 376 malaria patients who fulfilled the enrolment criteria as well as consented for the study were enrolled. Total 356 patients were followed up successfully up to 28 days. Overall, the adequate clinical and parasitological response was 98.9% and 99.4% with and without PCR correction respectively. No case of early treatment failure was observed. However, four cases (1.1%) of late parasitological failure were found from the Bastar district of Chhattisgarh. Genotyping of msp1 and msp2 confirmed 2 cases each of recrudescence and reinfection, respectively. Mutation analysis of k13 propeller gene showed one non-synonymous mutation Q613H in one isolate from Bastar. CONCLUSIONS: The study results showed that artemether-lumefantrine is highly effective in the treatment of uncomplicated P. falciparum malaria among all age groups. No functional mutation in k13 was found in the study area. The data from this study will be helpful in implementation of artemether-lumefantrine in case of treatment failure by artesunate plus sulfadoxine-pyrimethamine.


Asunto(s)
Antimaláricos/uso terapéutico , Combinación Arteméter y Lumefantrina/uso terapéutico , Enfermedades Endémicas/prevención & control , Malaria Falciparum/prevención & control , Adolescente , Adulto , Niño , Preescolar , Femenino , Humanos , India , Lactante , Masculino , Persona de Mediana Edad , Plasmodium falciparum/efectos de los fármacos , Adulto Joven
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