Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 69
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
PLoS Biol ; 22(4): e3002602, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38669296

RESUMEN

Mitofusins are large GTPases that trigger fusion of mitochondrial outer membranes. Similarly to the human mitofusin Mfn2, which also tethers mitochondria to the endoplasmic reticulum (ER), the yeast mitofusin Fzo1 stimulates contacts between Peroxisomes and Mitochondria when overexpressed. Yet, the physiological significance and function of these "PerMit" contacts remain unknown. Here, we demonstrate that Fzo1 naturally localizes to peroxisomes and promotes PerMit contacts in physiological conditions. These contacts are regulated through co-modulation of Fzo1 levels by the ubiquitin-proteasome system (UPS) and by the desaturation status of fatty acids (FAs). Contacts decrease under low FA desaturation but reach a maximum during high FA desaturation. High-throughput genetic screening combined with high-resolution cellular imaging reveal that Fzo1-mediated PerMit contacts favor the transit of peroxisomal citrate into mitochondria. In turn, citrate enters the TCA cycle to stimulate the mitochondrial membrane potential and maintain efficient mitochondrial fusion upon high FA desaturation. These findings thus unravel a mechanism by which inter-organelle contacts safeguard mitochondrial fusion.


Asunto(s)
Mitocondrias , Dinámicas Mitocondriales , Peroxisomas , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Peroxisomas/metabolismo , Dinámicas Mitocondriales/fisiología , Mitocondrias/metabolismo , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Ácidos Grasos/metabolismo , GTP Fosfohidrolasas/metabolismo , GTP Fosfohidrolasas/genética , Proteínas Mitocondriales/metabolismo , Proteínas Mitocondriales/genética , Retículo Endoplásmico/metabolismo , Proteínas de la Membrana/metabolismo , Proteínas de la Membrana/genética , Complejo de la Endopetidasa Proteasomal/metabolismo , Ciclo del Ácido Cítrico , Potencial de la Membrana Mitocondrial/fisiología , Membranas Mitocondriales/metabolismo , Humanos
2.
Small ; 19(15): e2205799, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36587980

RESUMEN

Filamentous fungi can synthesize a variety of nanoparticles (NPs), a process referred to as mycosynthesis that requires little energy input, do not require the use of harsh chemicals, occurs at near neutral pH, and do not produce toxic byproducts. While NP synthesis involves reactions between metal ions and exudates produced by the fungi, the chemical and biochemical parameters underlying this process remain poorly understood. Here, the role of fungal species and precursor salt on the mycosynthesis of zinc oxide (ZnO) NPs is investigated. This data demonstrates that all five fungal species tested are able to produce ZnO structures that can be morphologically classified into i) well-defined NPs, ii) coalesced/dissolving NPs, and iii) micron-sized square plates. Further, species-dependent preferences for these morphologies are observed, suggesting potential differences in the profile or concentration of the biochemical constituents in their individual exudates. This data also demonstrates that mycosynthesis of ZnO NPs is independent of the anion species, with nitrate, sulfate, and chloride showing no effect on NP production. These results enhance the understanding of factors controlling the mycosynthesis of ceramic NPs, supporting future studies that can enable control over the physical and chemical properties of NPs formed through this "green" synthesis method.


Asunto(s)
Nanopartículas del Metal , Nanopartículas , Óxido de Zinc , Óxido de Zinc/química , Nanopartículas/química , Metales , Iones , Nanopartículas del Metal/química
3.
Crit Rev Food Sci Nutr ; 63(22): 5813-5840, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-34996326

RESUMEN

Translation of traditional knowledge of herbs into a viable product for clinical use is still an uphill task. Piperine, a pungent alkaloid molecule derived from Piper nigrum and Piper longum possesses diverse pharmacological effects. Traditionally, pepper is used for arthritis, bronchitis, gastritis, diarrhea, snake bite, menstrual pain, fever, and bacterial infections, etc. The anti-inflammatory, antioxidant and immunomodulatory actions of piperine are the possible mechanisms behind its therapeutic potential. Various in-silico and experimental studies have shown piperine as a possible promising molecule in coronavirus disease (COVID-19), ebola, and dengue due to its immunomodulatory and antiviral activities. The other important clinical applications of piperine are due to its bio enhancing effect on drugs, by modulating, absorption in the gastrointestinal tract, altering activities of transporters like p-glycoprotein substrates, and modulating drug metabolism by altering the expression of cytochrome P450 or UDP-glucuronosyltransferase enzymes. Piperine attracted clinicians in treating patients with arthritis, metabolic syndrome, diabetes, skin infections, gastric and liver disorders. This review focused on systematic, evidence-based insight into the use of piperine in clinical settings and mechanistic details behind its therapeutic actions. Also, highlights a number of clinical trials of piperine at various stages exploring its clinical application in cancer, neurological, respiratory, and viral disease, etc.


Asunto(s)
Alcaloides , COVID-19 , Piper nigrum , Humanos , Alcaloides/farmacología , Alcaloides/uso terapéutico , Piperidinas/farmacología , Piperidinas/uso terapéutico , Benzodioxoles/farmacología , Benzodioxoles/uso terapéutico , Alcamidas Poliinsaturadas/farmacología , Alcamidas Poliinsaturadas/uso terapéutico , Piper nigrum/química
4.
Nano Lett ; 22(16): 6530-6536, 2022 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-35939762

RESUMEN

Isolated solid-state atomic defects with telecom optical transitions are ideal quantum photon emitters and spin qubits for applications in long-distance quantum communication networks. Prototypical telecom defects, such as erbium, suffer from poor photon emission rates, requiring photonic enhancement using resonant optical cavities. Moreover, many of the traditional hosts for erbium ions are not amenable to direct incorporation with existing integrated photonics platforms, limiting scalable fabrication of qubit-based devices. Here, we present a scalable approach toward CMOS-compatible telecom qubits by using erbium-doped titanium dioxide thin films grown atop silicon-on-insulator substrates. From this heterostructure, we have fabricated one-dimensional photonic crystal cavities demonstrating quality factors in excess of 5 × 104 and corresponding Purcell-enhanced optical emission rates of the erbium ensembles in excess of 200. This easily fabricated materials platform represents an important step toward realizing telecom quantum memories in a scalable qubit architecture compatible with mature silicon technologies.

5.
Org Biomol Chem ; 20(5): 963-979, 2022 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-35018952

RESUMEN

To a large extent, the physical and chemical properties of peptidomimetic molecules are dictated by the integrated heterocyclic scaffolds they contain. Heterocyclic moieties are introduced into a majority of peptide-mimicking molecules to modulate conformational flexibility, improve bioavailability, and fine-tune electronics, and in order to achieve potency similar to or better than that of the natural peptide ligand. This mini-review delineates recent developments, limited to the past five years, in the utility of selected saturated 3- to 6-membered heterocyclic moieties in peptidomimetic design. Also discussed is the chemistry involved in the synthesis of the azaheterocyclic scaffolds and the structural implications of the introduction of these azaheterocycles in peptide backbones as well as side chains of the peptide mimics.


Asunto(s)
Compuestos Aza/síntesis química , Compuestos Heterocíclicos/síntesis química , Peptidomiméticos/síntesis química , Animales , Antineoplásicos/síntesis química , Línea Celular Tumoral , Humanos , Conformación Proteica en Hélice alfa
6.
Indian J Clin Biochem ; 37(4): 466-472, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36262785

RESUMEN

The determination of monoclonal protein (M-protein) by SPE, IFE and SFLC assay is fundamental in the diagnosis of Plasma cell proliferative disorder (PCPD). In the present study, we seek to assess the diagnostic performance and concordance of these three techniques in un-treated PCPD patients. All new patients with dysproteinemia and/or suspected PCPD were included in this retrospective observational study. The baseline parameters were retrieved from electronic medical records. SPE was performed on gel electrophoresis system; monoclonal component was identified by IFE. SFLC assays were performed by nephelometry using a latex-enhanced immunoassay. Total 402 patients of PCPD were included (10.9% of MGUS/SMM and 89.1% of multiple myeloma). The combination of SPE + rSFLC (ratio of kappa/lambda light chain) and SPE + IFE + rSFLC was able to detect M-protein across all subgroups of patients. In 61 patients, rSFLC values were within normal range (54.5% of MGUS/SMM and 10.3% of MM) and was more commonly seen with IgG lambda M-protein (57.4% vs. all-others). The median dFLC value, among these patients, was higher for MM than MGUS/SMM patients (23.8 vs. 14.4 mg/L, respectively). The combination of SPE and rSFLC can be reliably used to detect M-protein in PCPD patients. In a small subgroup of MM patients, despite the presence of an intact immunoglobulin (M-protein), the rSFLC is not abnormal. Historically, these patients should respond better to treatment. However, a further follow-up analysis with more number of such patients would be advantageous for better understanding.

7.
EMBO Rep ; 20(11): e48150, 2019 11 05.
Artículo en Inglés | MEDLINE | ID: mdl-31544310

RESUMEN

STK38 (also known as NDR1) is a Hippo pathway serine/threonine protein kinase with multifarious functions in normal and cancer cells. Using a context-dependent proximity-labeling assay, we identify more than 250 partners of STK38 and find that STK38 modulates its partnership depending on the cellular context by increasing its association with cytoplasmic proteins upon nutrient starvation-induced autophagy and with nuclear ones during ECM detachment. We show that STK38 shuttles between the nucleus and the cytoplasm and that its nuclear exit depends on both XPO1 (aka exportin-1, CRM1) and STK38 kinase activity. We further uncover that STK38 modulates XPO1 export activity by phosphorylating XPO1 on serine 1055, thus regulating its own nuclear exit. We expand our model to other cellular contexts by discovering that XPO1 phosphorylation by STK38 regulates also the nuclear exit of Beclin1 and YAP1, key regulator of autophagy and transcriptional effector, respectively. Collectively, our results reveal STK38 as an activator of XPO1, behaving as a gatekeeper of nuclear export. These observations establish a novel mechanism of XPO1-dependent cargo export regulation by phosphorylation of XPO1's C-terminal auto-inhibitory domain.


Asunto(s)
Autofagia , Núcleo Celular/metabolismo , Carioferinas/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Receptores Citoplasmáticos y Nucleares/metabolismo , Proteínas Portadoras/metabolismo , Cromatografía Liquida , Biología Computacional/métodos , Vía de Señalización Hippo , Humanos , Fosforilación , Unión Proteica , Mapeo de Interacción de Proteínas , Transporte de Proteínas , Transducción de Señal , Espectrometría de Masas en Tándem , Proteína Exportina 1
8.
Diabetologia ; 63(11): 2434-2445, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32865597

RESUMEN

AIMS/HYPOTHESIS: Liraglutide, a daily injectable glucagon-like peptide-1 receptor (GLP-1r) agonist, has been shown to reduce liver fat content (LFC) in humans. Data regarding the effect of dulaglutide, a once-weekly GLP-1r agonist, on human LFC are scarce. This study examined the effect of dulaglutide on LFC in individuals with type 2 diabetes and non-alcoholic fatty liver disease (NAFLD). METHODS: Effect of dulaglutide on liver fat (D-LIFT) was a 24 week, open-label, parallel-group, randomised controlled trial to determine the effect of dulaglutide on liver fat at a tertiary care centre in India. Adults (n = 64), who had type 2 diabetes and MRI-derived proton density fat fraction-assessed LFC of ≥6.0% at baseline, were randomly assigned to receive dulaglutide weekly for 24 weeks (add-on to usual care) or usual care, based on a predefined computer-generated number with a 1:1 allocation that was concealed using serially numbered, opaque, sealed envelopes. The primary endpoint was the difference of the change in LFC from 0 (baseline) to 24 weeks between groups. The secondary outcome measures included the difference of the change in pancreatic fat content (PFC), change in liver stiffness measurement (LSM in kPa) measured by vibration-controlled transient elastography, and change in liver enzymes. RESULTS: Eighty-eight patients were screened; 32 were randomly assigned to the dulaglutide group and 32 to the control group. Overall, 52 participants were included for per-protocol analysis: those who had MRI-PDFF data at baseline and week 24. Dulaglutide treatment resulted in a control-corrected absolute change in LFC of -3.5% (95% CI -6.6, -0.4; p = 0.025) and relative change of -26.4% (-44.2, -8.6; p = 0.004), corresponding to a 2.6-fold greater reduction. Dulaglutide-treated participants also showed a significant reduction in γ-glutamyl transpeptidase (GGT) levels (mean between-group difference -13.1 U/l [95% CI -24.4, -1.8]; p = 0.025) and non-significant reductions in aspartate aminotransferase (AST) (-9.3 U/l [-19.5, 1.0]; p = 0.075) and alanine aminotransferase (ALT) levels (-13.1 U/l [-24.4, 2.5]; p = 0.10). Absolute changes in PFC (-1.4% [-3.2, 0.3]; p = 0.106) and LSM (-1.31 kPa [-2.99, 0.37]; p = 0.123) were not significant when comparing the two groups. There were no serious drug-related adverse events. CONCLUSIONS/INTERPRETATION: When included in the standard treatment for type 2 diabetes, dulaglutide significantly reduces LFC and improves GGT levels in participants with NAFLD. There were non-significant reductions in PFC, liver stiffness, serum AST and serum ALT levels. Dulaglutide could be considered for the early treatment of NAFLD in patients with type 2 diabetes. TRIAL REGISTRATION: ClinicalTrials.gov NCT03590626 FUNDING: The current study was supported by an investigator-initiated study grant from Medanta-The Medicity's departmental research fund and a grant from the Endocrine and Diabetes Foundation (EDF), India. Graphical abstract.


Asunto(s)
Diabetes Mellitus Tipo 2/tratamiento farmacológico , Liraglutida/uso terapéutico , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Alanina Transaminasa/metabolismo , Aspartato Aminotransferasas/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Péptidos Similares al Glucagón/análogos & derivados , Humanos , Hipoglucemiantes/uso terapéutico , Fragmentos Fc de Inmunoglobulinas , Hígado , Pruebas de Función Hepática , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Proteínas Recombinantes de Fusión
9.
Cytokine ; 113: 200-215, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30001865

RESUMEN

The shift of macrophage and T-cell repertoires towards proinflammatory cytokine signalling ensures the generation of host-protective machinery that is otherwise compromised in cases of the intracellular Leishmania parasite. Different groups have attempted to restore host protective immunity. These vaccine candidates showed good responses and protective effects in murine models, but they generally failed during human trials. In the present study, we evaluated the effect of 97 kDa recombinant nucleoporin-93 of Leishmania donovani (rLd-NUP93) on mononuclear cells in healthy and treated visceral leishmaniasis (VL) patients and on THP-1 cell lines. rLd-NUP93 stimulation increased the expression of the early lymphocyte activation marker CD69 on CD4+ and CD8+ T cells. The expression of the host protective pro-inflammatory cytokines IFN-γ, IL-12 and TNF-α was increased, with a corresponding down-regulation of IL-10 and TGF-ß upon rLd-NUP93 stimulation. This immune polarization resulted in the up-regulation of NF-κB p50 with scant expression of SMAD-4. Augmenting lymphocyte proliferation upon priming with rLd-NUP93 ensured its potential for activation and generation of strong T-cell mediated immune responses. This stimulation extended the leishmanicidal activity of macrophages by releasing high amounts of reactive oxygen species (ROS). Further, the leishmanicidal activity of macrophages was intensified by the elevated production of nitric oxide (NO). The fact that this antigen was earlier reported in circulating immune complexes of VL patients highlights its antigenic importance. In addition, in silico analysis suggested the presence of MHC class I and II-restricted epitopes that proficiently trigger CD8+ and CD4+ T-cells, respectively. This study reported that rLd-NUP93 was an effective immunoprophylactic agent that can be explored in future vaccine design.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Inmunidad Celular , Leishmania donovani/inmunología , Leishmaniasis Visceral/inmunología , Activación de Linfocitos , Macrófagos/inmunología , Proteínas de Complejo Poro Nuclear/inmunología , Proteínas Protozoarias/inmunología , Adulto , Animales , Femenino , Humanos , Leishmania donovani/genética , Vacunas contra la Leishmaniasis/genética , Vacunas contra la Leishmaniasis/inmunología , Leishmaniasis Visceral/genética , Leishmaniasis Visceral/prevención & control , Masculino , Persona de Mediana Edad , Proteínas de Complejo Poro Nuclear/genética , Proteínas Protozoarias/genética , Conejos , Células THP-1
10.
Phys Chem Chem Phys ; 21(27): 14701-14712, 2019 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-31218309

RESUMEN

The paradigm that chemical synthesis reduces the sintering temperature as compared to solid state synthesis seems to be violated in the case of the PrBaCo2O6-δ double perovskite. The sintering temperatures for pure phase samples synthesized through the solid state route (P-SSR) and the auto-combustion route (P-ACR) were found to be 1050 and 1150 °C, respectively. The porous microstructure of P-SSR is suitable for SOFC cathode materials while that of P-ACR is pore free. High-resolution transmission electron microscopy, Raman and scanning tunneling microscopy studies reveal that there is crystal growth on a smooth surface with a preferred orientation. Our results show that this anomalous synthesis behaviour is due to anisotropic surface nucleation growth. Thermodynamically, the higher decomposition temperature in the chemical route is due to stronger electron-phonon coupling and the higher value of change in entropy. The variation in the Co-O-Co bond angle reveals Jahn-Teller vibrational anisotropy in the-b plane leading to the anisotropic synthesis behaviour. This anisotropy is the reason for the violation of the paradigm.

11.
Cell Immunol ; 332: 51-57, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30049412

RESUMEN

Visceral leishmaniasis (VL) is a disease caused by protozoan species of the genus Leishmania and is transmitted through bites from the Phlebotomus sand fly; it is associated with considerable morbidity and mortality in many parts of world, including India. Reports on the protective role played by saliva proteins of Lutozomyia longipalpis, Phlebotomus papatasi and Phlebotomus duboscqi. are available. However, no studies have explored the salivary proteins of P. argentipes, which is the known proven vector for the transmission of VL in the Indian sub-continent. Herein we revealed the presence of two proteins of 14.2 and one protein of 13.6 kDa in Indian strain P. argentipes which is absolute identical to previously reported protein of SP15 family (PagSP01, PagSP02 and PagSP07) of P. argentipes of NIH colony, USA. In an experimental study on P. argentipes from Bihar, India, we demonstrated that a strong humoral and cellular immune response was triggered to reduce the concomitant Leishmania load in groups of immunized mice. The immunized group produced a considerable amount of IgG antibodies, and their splenocytes generated TH1 cytokines (IL-12, IFN-γ) with the support of delayed-type hypersensitivity (DTH) reactivity in such mice at the challenged site. We summarize from our data that some identical proteins to previous from SP15 family protein of 14.2 and 13.6 kDa molecular size, derived from Indian P. argentipes and reported its first time, can also be significant in resolution of VL infection after modulation of host protective T cell response in VL.


Asunto(s)
Leishmania/inmunología , Leishmaniasis Visceral/inmunología , Phlebotomus/inmunología , Psychodidae/inmunología , Saliva/inmunología , Proteínas y Péptidos Salivales/inmunología , Animales , Citocinas/inmunología , Femenino , Inmunidad Celular/inmunología , Inmunidad Humoral/inmunología , Inmunoglobulina G/inmunología , Ratones , Ratones Endogámicos BALB C , Células TH1/inmunología
12.
Pediatr Blood Cancer ; 65(12): e27366, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30168245

RESUMEN

Karyotyping along with a 3-probe fluorescence in situ hybridization (FISH) strategy was used to risk stratify therapy in 303 children with B-cell precursor acute lymphoblastic leukaemia. Of the 166 patients risk stratified, karyotype identified 91 (55%). FISH identified all karyotypes accurately, with the exception of hypodiploidy, and risk stratified an additional 75 patients. The frequency of ETV6-RUNX1 is lower and high hyperdiploidy, higher than reported in the west. An adapted 3-probe FISH strategy identified two patients with ETV6-ABL1 fusion who received imatinib. In limited-resource settings, a 3-probe FISH approach provides a practical approach for risk-stratified therapy in childhood ALL.


Asunto(s)
Subunidad alfa 2 del Factor de Unión al Sitio Principal/genética , Hibridación Fluorescente in Situ , Cariotipificación , Proteínas de Fusión Oncogénica/genética , Ploidias , Leucemia-Linfoma Linfoblástico de Células Precursoras B/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Adolescente , Niño , Preescolar , Femenino , Humanos , Mesilato de Imatinib/administración & dosificación , Lactante , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras B/tratamiento farmacológico , Medición de Riesgo
13.
Parasitology ; 145(3): 292-306, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29140228

RESUMEN

Immunoactivation depends upon the antigen potential to modulate T-cell repertoires. The present study has enumerated the effect of 61 kDa recombinant Leishmania donovani co-factor-independent phosphoglycerate mutase (rLd-iPGAM) on mononuclear cells of healthy and treated visceral leishmaniasis subjects as well as on THP-1 cell line. rLd-iPGAM stimulation induced higher expression of interleukin-1ß (IL-1ß) in the phagocytic cell, its receptor and CD69 on T-cell subsets. These cellular activations resulted in upregulation of host-protective cytokines IL-2, IL-12, IL-17, tumour necrosis factor-α and interferon-γ, and downregulation of IL-4, IL-10 and tumour growth factor-ß. This immune polarization was also evidenced by upregulation of nuclear factor-κ light-chain enhancer of activated B cells p50 and regulated expression of suppressor of mother against decapentaplegic protein-4. rLd-iPGAM stimulation also promoted lymphocyte proliferation and boosted the leishmaniacidal activity of macrophages by upregulating reactive oxygen species. It also induced 1·8-fold higher release of nitric oxide (NO) by promoting the transcription of inducible nitric oxide synthase gene. Besides, in silico analysis suggested the presence of major histocompatibility complex class I and II restricted epitopes, which can proficiently trigger CD8+ and CD4+ cells, respectively. This study reports rLd-iPGAM as an effective immunoprophylactic agent, which can be used in future vaccine design.


Asunto(s)
Epítopos de Linfocito T/inmunología , Leishmania donovani/enzimología , Leishmania donovani/inmunología , Macrófagos/inmunología , Fosfoglicerato Mutasa/inmunología , Proteínas Recombinantes/farmacología , Línea Celular , Coenzimas/deficiencia , Coenzimas/genética , Simulación por Computador , Citocinas/efectos de los fármacos , Citocinas/inmunología , Epítopos de Linfocito T/efectos de los fármacos , Genes MHC Clase I/inmunología , Genes MHC Clase II/inmunología , Humanos , Interleucina-1beta/efectos de los fármacos , Interleucina-1beta/inmunología , Leishmaniasis Visceral/inmunología , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/inmunología , Leucocitos Mononucleares/parasitología , Activación de Linfocitos/efectos de los fármacos , Macrófagos/parasitología , Subunidad p50 de NF-kappa B/efectos de los fármacos , Subunidad p50 de NF-kappa B/genética , Óxido Nítrico , Óxido Nítrico Sintasa de Tipo II/efectos de los fármacos , Fosfoglicerato Mutasa/genética , Fosfoglicerato Mutasa/farmacología , Proteínas Recombinantes/genética , Proteínas Recombinantes/inmunología , Células TH1
15.
Cytokine ; 86: 79-85, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27484246

RESUMEN

Currently the main concerns regarding control of visceral leishmaniasis (VL) caused by L. donovani are immunosuppression, relating toxicity of anti-leishmanial drug and little development in appropriate vaccine and vector (P. argentipes) control. Reports available from ex-vivo studies reflect significance of vector salivary gland homogenate (SGH) in reverting immunosuppression of infected VL subjects and as such the immunogenic nature of SGH can be a strategy to modulate immune system and anti-leishmanial function to enable immune response to control the disease. Several related studies also identified a better utility of vector anti-saliva antibodies in achieving such effects by an adoptive transfer approach instead of direct stimulation with SGH protein. However, conclusive evidences on VL cases are far beyond satisfactory to suggest role of SGH into modulation of host immune response in VL subjects in India. This study was under taken to make comparison on change in cytokines (TH1 and TH2) response pattern and anti-leishmanial macrophage (Mϕ) function following stimulation of their PBMCS with SGH protein derived from P. argentipes sand fly vector for VL or anti SGH antibodies raised in rabbit. This study reports for the first time that L. donovani sensitized healthy subject demonstrates an up-regulated Interferon-γ (TH1) and down regulate Interleukin-10 (TH2) production following stimulation of their PBMCs by P. argentipes anti-saliva antibodies accompanied with an improvement in anti-leishmanial Mϕ function for nitric oxide (NO) production. Subsequent experiments suggest that P. argentipes based anti-SGH antibodies when used to stimulate LD infected PBMCs in healthy subjects resulted in better clearance of Leishmania amastigotes load compare to SGH protein. Possibly the immunogenic components of anti-saliva an antibody maintains the level of protective cytokine (INF-γ) and seems to restrict the infection by host protection by vector saliva.


Asunto(s)
Anticuerpos/inmunología , Leishmaniasis Visceral/inmunología , Macrófagos/inmunología , Phlebotomus/inmunología , Glándulas Salivales/inmunología , Células TH1/inmunología , Animales , Citocinas/biosíntesis , Citocinas/inmunología , Humanos , Interferón gamma/genética , Interferón gamma/inmunología , Interleucina-10/genética , Interleucina-10/inmunología , Leishmania donovani/inmunología , Leishmaniasis Visceral/prevención & control , Leucocitos Mononucleares/inmunología , Macrófagos/metabolismo , Óxido Nítrico/biosíntesis , Carga de Parásitos , Phlebotomus/química , Conejos , Glándulas Salivales/química , Proteínas y Péptidos Salivales/inmunología
16.
Bioorg Med Chem Lett ; 25(21): 4838-4842, 2015 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-26152429

RESUMEN

Both the Wnt/ß-catenin signaling pathway and small GTPases of the ADP-ribosylation factors (ARF) family play important roles in regulating cell development, homeostasis and fate. The previous report of QS11, a small molecule Wnt synergist that binds to ARF GTPase-activating protein 1 (ARFGAP1), suggests a role for ARFGAP1 in the Wnt/ß-catenin pathway. However, direct inhibition of enzymatic activity of ARFGAP1 by QS11 has not been established. Whether ARFGAP1 is the only target that contributes to QS11's Wnt synergy is also not clear. Here we present structure-activity relationship (SAR) studies of QS11 analogs in two assays: direct inhibition of enzymatic activity of purified ARFGAP1 protein and cellular activation of the Wnt/ß-catenin pathway. The results confirm the direct inhibition of ARFGAP1 by QS11, and also suggest the presence of other potential cellular targets of QS11.


Asunto(s)
Proteínas Activadoras de GTPasa/antagonistas & inhibidores , Purinas/química , Purinas/farmacología , Proteínas Wnt/agonistas , Vía de Señalización Wnt/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Proteínas Activadoras de GTPasa/metabolismo , Humanos , Estructura Molecular , Purinas/síntesis química , Relación Estructura-Actividad , beta Catenina/metabolismo
17.
Indian J Clin Biochem ; 29(1): 29-37, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24478546

RESUMEN

Arsenic a metalloid and environmental contaminated has been found to be associated with public health problems in the affected areas. It is naturally occurred in groundwater and its accumulation in plant and animals leads to toxicity in several tissues most notably hepatic organ. Arsenic exposures (3 mg/kg body weight/day for 30 days) in mice exhibited increased arsenic and Zn levels in hepatocytes associated with enhanced oxidative stress in hepatocytes while there were no significantly changes were observed in Cu level. An increase in the lipid peroxidation and decrease in the levels of reduced glutathione and activity of superoxide dismutase, catalase, and glutathione peroxidase were observed in arsenic treated mice as compared to controls. Arsenic exposure in mice also caused a significant change in serum biomarkers in the SGOT, SGPT and creatinine as compared to the controls. There were no significant changes in the serum levels of total protein in these mice. Co-administration of arsenic and fruit extract of amla (500 mg/kg body weight/day for 30 days) caused a significant reduction of arsenic transference associated with significantly decreases hepatic arsenic levels and balanced the antioxidant enzyme and levels of serum hepatic enzymes like SGOT and SGPT. The results of the present study clearly demonstrate the antioxidant property of amla that could be responsible for its protective efficacy in arsenic induced hepatic toxicity.

18.
Beilstein J Org Chem ; 10: 1919-32, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25246951

RESUMEN

(1H-Benzo[d][1,2,3]triazol-1-yloxy)tris(dimethylamino)phosphonium hexafluorophosphate (BOP), 1H-benzo[d][1,2,3]triazol-1-yl 4-methylbenzenesulfonate (Bt-OTs), and 3H-[1,2,3]triazolo[4,5-b]pyridine-3-yl 4-methylbenzenesulfonate (At-OTs) are classically utilized in peptide synthesis for amide-bond formation. However, a previously undescribed reaction of these compounds with alcohols in the presence of a base, leads to 1-alkoxy-1H-benzo- (Bt-OR) and 7-azabenzotriazoles (At-OR). Although BOP undergoes reactions with alcohols to furnish 1-alkoxy-1H-benzotriazoles, Bt-OTs proved to be superior. Both, primary and secondary alcohols undergo reaction under generally mild reaction conditions. Correspondingly, 1-alkoxy-1H-7-azabenzotriazoles were synthesized from At-OTs. Mechanistically, there are three pathways by which these peptide-coupling agents can react with alcohols. From (31)P{(1)H}, [(18)O]-labeling, and other chemical experiments, phosphonium and tosylate derivatives of alcohols seem to be intermediates. These then react with BtO(-) and AtO(-) produced in situ. In order to demonstrate broader utility, this novel reaction has been used to prepare a series of acyclic nucleoside-like compounds. Because BtO(-) is a nucleofuge, several Bt-OCH2Ar substrates have been evaluated in nucleophilic substitution reactions. Finally, the possible formation of Pd π-allyl complexes by departure of BtO(-) has been queried. Thus, alpha-allylation of three cyclic ketones was evaluated with 1-(cinnamyloxy)-1H-benzo[d][1,2,3]triazole, via in situ formation of pyrrolidine enamines and Pd catalysis.

19.
Cureus ; 16(1): e52961, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38406148

RESUMEN

Background and aim The regional anesthesia technique is commonly used for upper extremity surgery as an alternative to general anesthesia. The study aimed to compare the efficacy of infraclavicular brachial plexus block (BPB) and a combination of infraclavicular brachial plexus block with suprascapular nerve block for postoperative analgesia in patients undergoing shoulder surgeries. Method A total of 62 patients of both sexes with the American Society of Anaesthesiologists (ASA) physical status I/II/III, aged between 18 and 65 years, and undergoing shoulder surgery, were included in this prospective, single-blinded, randomized controlled trial. Patients were equally allocated into two groups: 31 in group A and 31 in group B. After pre-anesthetic evaluation, the purpose and protocol of the study were explained to patients, and informed consent was obtained. Thirty-one patients in group A were given infraclavicular brachial plexus block using 30 ml 0.375% bupivacaine while 31 patients in group B were given a combination of infraclavicular brachial plexus block using 30 ml 0.375% bupivacaine and suprascapular nerve block using 5 ml 0.375% bupivacaine. Blocks were given using ultrasound guidance and a peripheral nerve stimulator; the suprascapular block was given in the sitting position while the infraclavicular block was provided in the supine position. General anesthesia was administered in the operation theatre in the supine position after the administration of blocks. The pain was assessed using the visual analog scale (VAS) and the satisfaction score was assessed by the numeric rating scale (NRS). The Mann-Whitney U test was applied for comparison of pain between the two groups. The chi-square test was utilized for comparing the categorical variables. Result The postoperative pain was significantly lower (p<0.001) in group B as compared to group A at all the periods of observation, i.e., 0h (2.77±0.72 vs. 5.42±0.77), 6h (3.89±0.70 vs. 5.94±0.73), 12h (5.66±0.93 vs. 6.58±0.88), and 24h (6.16±0.80 vs. 6.74±0.90). These findings illustrate that group B patients who received a combination of infraclavicular brachial plexus block and suprascapular nerve block for shoulder surgeries had better pain relief than group A patients who received only the infraclavicular approach. The mean NRS score of patient satisfaction in group B (7.26±0.58) was significantly higher (p<0.001) in comparison to group A (6.16±0.64). Diaphragmatic palsy was observed in only one case in group A and none in group B. No other complication was observed in any of the patients during the study period. Conclusion The combination of infraclavicular brachial plexus block and suprascapular nerve block displays a positive postoperative analgesic profile with less usage of rescue analgesic doses and better patient satisfaction after shoulder surgery.

20.
Indian J Anaesth ; 68(4): 329-333, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38586263

RESUMEN

Background and Aims: Apprehension of pain due to a spinal needle is often a cause of anxiety and refusal. ShotBlocker provides non-painful physical stimulation, inhibiting pain perception. The vapocoolant spray contains ethyl chloride vapours, rapidly raising the skin temperature and hampering the transmission of noxious stimuli. The present study compared the effectiveness of the ShotBlocker device and the vapocoolant spray in reducing spinal needle-associated pain in primigravida women undergoing elective lower-segment caesarean section (LSCS). Methods: We enroled 144 primigravida women undergoing elective LSCS and were randomised to Group SB (the ShotBlocker device was firmly pressed over the skin, and the spinal needle was inserted through its slit), Group V (the vapocoolant spray was applied at the puncture site before spinal needle insertion), and Group C (received local infiltration before spinal anaesthesia (SA)). The groups were compared for needle-associated pain and patient satisfaction using a 10-point visual analogue scale (VAS) and a 3-point Likert scale. Results: The mean (standard deviation) [95% confidence interval (CI)] VAS scores of Group SB 3.85 (0.74) [3.64, 4.07] and Group V 3.04 (0.74) [2.83, 3.26] were significantly lower than that of Group C 5.19 (0.92) [3.28, 3.62]). On the Likert scale, the maximum number of patients in the vapocoolant group (64.6%) responded satisfactorily, while in the control group, the majority (62.5%) of participants responded dissatisfied (P < 0.001). Conclusion: Both the ShotBlocker and vapocoolant spray reduce needle puncture-associated pain before SA in primigravida patients undergoing elective LSCS. However, the vapocoolant spray is more beneficial in reducing spinal needle-associated pain than the ShotBlocker device.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA