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1.
PLoS Comput Biol ; 17(4): e1008820, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33830995

RESUMO

Variation in the acoustic structure of vocal signals is important to communicate social information. However, relatively little is known about the features that receivers extract to decipher relevant social information. Here, we took an expansive, bottom-up approach to delineate the feature space that could be important for processing social information in zebra finch song. Using operant techniques, we discovered that female zebra finches can consistently discriminate brief song phrases ("motifs") from different social contexts. We then applied machine learning algorithms to classify motifs based on thousands of time-series features and to uncover acoustic features for motif discrimination. In addition to highlighting classic acoustic features, the resulting algorithm revealed novel features for song discrimination, for example, measures of time irreversibility (i.e., the degree to which the statistical properties of the actual and time-reversed signal differ). Moreover, the algorithm accurately predicted female performance on individual motif exemplars. These data underscore and expand the promise of broad time-series phenotyping to acoustic analyses and social decision-making.


Assuntos
Tentilhões , Discriminação Social , Vocalização Animal , Algoritmos , Animais , Percepção Auditiva , Feminino , Aprendizado de Máquina , Masculino , Fenótipo
2.
Biol Res ; 54(1): 9, 2021 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-33712084

RESUMO

BACKGROUND: PGF2α is essential for the induction of the corpus luteum regression which in turn reduces progesterone production. Early growth response (EGR) proteins are Cys2-His2-type zinc-finger transcription factor that are strongly linked to cellular proliferation, survival and apoptosis. Rapid elevation of EGR1 was observed after luteolytic dose of PGF2α. EGR1 is involved in the transactivation of many genes, including TGFß1, which plays an important role during luteal regression. METHODS: The current study was conducted in buffalo luteal cells with the aim to better understand the role of EGR1 in transactivation of TGFß1 during PGF2α induced luteal regression. Luteal cells from mid stage corpus luteum of buffalo were cultured and treated with different doses of PGF2α for different time durations. Relative expression of mRNAs encoding for enzymes within the progesterone biosynthetic pathway (3ßHSD, CYP11A1 and StAR); Caspase 3; AKT were analyzed to confirm the occurrence of luteolytic event. To determine if EGR1 is involved in the PGF2α induced luteal regression via induction of TGFß1 expression, we knocked out the EGR1 gene by using CRISPR/Cas9. RESULT: The present experiment determined whether EGR1 protein expression in luteal cells was responsive to PGF2α treatment. Quantification of EGR1 and TGFß1 mRNA showed significant up regulation in luteal cells of buffalo at 12 h post PGF2α induction. In order to validate the role of PGF2α on stimulating the expression of TGFß1 by an EGR1 dependent mechanism we knocked out EGR1. The EGR1 ablated luteal cells were stimulated with PGF2α and it was observed that EGR1 KO did not modulate the PGF2α induced expression of TGFß1. In PGF2α treated EGR1 KO luteal cell, the mRNA expression of Caspase 3 was significantly increased compared to PGF2α treated wild type luteal cells maintained for 12 h. We also studied the influence of EGR1 on steroidogenesis. The EGR1 KO luteal cells with PGF2α treatment showed no substantial difference either in the progesterone concentration or in StAR mRNA expression with PGF2α-treated wild type luteal cells. CONCLUSION: These results suggest that EGR1 signaling is not the only factor which plays a role in the regulation of PGF2α induced TGFß1 signaling for luteolysis.


Assuntos
Búfalos , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Corpo Lúteo/fisiologia , Dinoprosta , Proteína 1 de Resposta de Crescimento Precoce/fisiologia , Luteólise , Animais , Células Cultivadas , Corpo Lúteo/citologia , Dinoprosta/farmacologia , Feminino , Regulação da Expressão Gênica , Transdução de Sinais , Fator de Crescimento Transformador beta1/fisiologia
3.
Inorg Chem ; 59(9): 6351-6358, 2020 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-32283022

RESUMO

In this report, the synthesis and characterization of two bis-cyclometalated iridium(III) complexes are presented. Single-crystal X-ray diffraction shows that [Ir(ppy)2(4,4'-bis(diethylphosphonomethyl)-2,2'-bipyridine)]PF6 adopts a pseudooctahedral geometry. The complexes have an absorption feature in the near-visible-UV region and emit green light with excited-state lifetimes in hundreds of nanoseconds. The redox properties of these complexes show reversible behavior for both oxidative and reductive events. [Ir(ppy)2(4,4'-bis(phosphonomethyl)-2,2'-bipyridine)]PF6 readily binds to metal oxide supports, like nanostructured SnIV-doped In2O3 and TiO2, while still retaining reversible redox chemistry. When incorporated as the photoanode in dye-sensitized solar cells, the devices exhibit open-circuit voltages of >1 V, which is a testament to their strength of these iridium(III) complexes as photochemical oxidants.

4.
Angew Chem Int Ed Engl ; 59(46): 20328-20332, 2020 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-32352201

RESUMO

Current bacterial RNA switches suffer from lack of versatile inputs and are difficult to engineer. We present versatile and modular RNA switches that are trans-encoded and based on tRNA-mimicking structures (TMSs). These switches provide a high degree of freedom for reengineering and can thus be designed to accept a wide range of inputs, including RNA, small molecules, and proteins. This powerful approach enables control of the translation of protein expression from plasmid and genome DNA.


Assuntos
RNA Bacteriano/genética , Expressão Gênica , Proteínas de Fluorescência Verde/genética , Biologia Sintética
5.
Cell Physiol Biochem ; 52(3): 532-552, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30897320

RESUMO

BACKGROUND/AIMS: Thrombospondins (TSPs) are large multi-modular proteins, identified as natural angiogenesis inhibitors that exert their activity by binding to CD36 and CD47 receptors. The anti-angiogenic effect of TSPs in luteal regression of water buffalo has not been addressed. The present study characterized the expression pattern and localization of TSPs and their receptors in ovarian corpus luteum during different stages of development in buffalo. This study also elucidated the effect of exogenous Thrombospondin1 (TSP1) or the knocking out of the endogenous protein on luteal cell viability and function. Further, the in vitro transcriptional interaction of TSP1 with hormones, LH, PGF2α and angiogenic growth factors, VEGF and FGF2 were also evaluated. METHODS: First, the CLs were classified into four groups based on macroscopic observation and progesterone concentration. mRNA expression of examined factors was measured by qPCR, localization by immunoblotting and immunohistochemistry. TSP1 was knocked out (KO) in cultured luteal cells isolated from late luteal stage CLs (day 1116) by CRISPR/Cas9 mediated gene editing technology in order to functionally validate the TSP1 gene. Isolated cells from late stage CLs were also stimulated with different doses of TSP1, LH, PGF2α, VEGF and FGF2 for various time intervals to determine transcriptional regulation of thrombospondins. RESULTS: mRNA expression of TSPs and their receptors were found to be significantly higher in late and regressed stage of CL as compared to other groups which was consistent with the findings of immunoblotting and immunolocalization experiments. It was observed that TSP1 induced apoptosis, down regulated angiogenic growth factors, VEGF and FGF2 and attenuated progesterone production in cultured luteal cells. However, knocking out of endogenous TSP1 with CRISPR/Cas9 system improved the viability of luteal cells, progesterone synthesis and upregulated the expression of VEGF and FGF2 in the KO luteal cells. PGF2α induced the upregulation of TSPs and Caspase 3 transcripts, whereas treatment with LH and angiogenic growth factors (VEGF and FGF2) down regulated the TSP system in luteal cells. CONCLUSION: Collectively, these data provide evidence that thrombospondins along with their receptors are expressed at varying levels in different stages of CL progression with maximum expression during the late and regressing stages. These results are consistent with the hypothesis that thrombospondins stimulated by PGF2α plays an essential modulatory role in bringing about structural and functional luteolysis in buffalo.


Assuntos
Sistemas CRISPR-Cas/genética , Corpo Lúteo/metabolismo , Edição de Genes , Trombospondina 1/genética , Animais , Apoptose , Búfalos/metabolismo , Antígenos CD36/genética , Antígenos CD36/metabolismo , Antígeno CD47/genética , Antígeno CD47/metabolismo , Caspase 3/genética , Caspase 3/metabolismo , Sobrevivência Celular , Corpo Lúteo/citologia , Corpo Lúteo/patologia , Dinoprosta/metabolismo , Regulação para Baixo , Feminino , Fator 2 de Crescimento de Fibroblastos/genética , Fator 2 de Crescimento de Fibroblastos/metabolismo , Trombospondina 1/metabolismo , Trombospondinas/genética , Trombospondinas/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
6.
Reprod Fertil Dev ; 31(4): 751-759, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30509339

RESUMO

The present study examined the effect of exogenous thrombospondin 1 (TSP1) on the steroidogenic function of luteal cells cultured invitro. Furthermore, the transcriptional interaction of insulin with TSP1 and its receptor, cluster of differentiation 36 (CD36) were also investigated. At the highest dose (500ngmL-1) TSP1 significantly downregulated the expression of the angiogenic marker von Willebrand factor (vWF) and progesterone production in cultured luteal cells. Moreover, the simultaneous upregulation in the expression of caspase 3 by exogenous TSP1 was consistent with a reduction in the number of viable luteal cells as determined by 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltertrazolium bromide (MTT) assay after 72h of culture. However, the expression of critical enzymes in the progesterone synthetic pathway was not significantly modulated by treatment with TSP1 in cultured luteal cells. Knocking out of endogenous TSP1 with the clustered regularly interspaced short palindromic repeats (CRISPR)/ CRISPRassociated protein9 (Cas9) system improved the viability of luteal cells as well as increasing progesterone production and decreasing caspase 3 activation. Insulin treatment suppressed the expression of TSP1 and CD36 in cultured luteal cells in a dose- and time-dependent manner. To conclude, TSP1 acts as a negative endogenous regulator of angiogenesis that attenuates progesterone production, possibly by reducing the number of luteal cells via apoptosis during luteal regression, whereas insulin as a luteinising signal may have inhibited the thrombospondin system for the efficient development of luteal function.


Assuntos
Insulina/farmacologia , Células Lúteas/efeitos dos fármacos , Trombospondinas/farmacologia , Animais , Búfalos , Antígenos CD36/metabolismo , Caspase 3/metabolismo , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Relação Dose-Resposta a Droga , Feminino , Células Lúteas/metabolismo , Progesterona/metabolismo , Receptor de Insulina/metabolismo , Trombospondinas/genética , Fatores de Tempo , Regulação para Cima/efeitos dos fármacos
7.
Cytokine ; 110: 333-343, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29655568

RESUMO

The present investigation was undertaken to assess the result of pretreatment of luteolin in sepsis-induced acute lung injury in mice and its mechanism of action. Luteolin was administered intraperitoneally one hour before caecal ligation and puncture (CLP) surgery in mice. Acute lung injury was assessed by estimation of different parameters like lung edema, protein content, cytokines level, oxidative stress, inducible nitric oxide synthase (iNOS), intercellular adhesion molecule (ICAM)-1 expression and histopathology. Pretreatment of mice with luteolin showed decrease lung edema and protein content in tissue and bronchoalveolar lavage fluid (BALF). However, mice pretreated with luteolin showed reduction (p = 0.92) in blood and lung tissue bacterial counts however it was non significant. Further, luteolin showed significant reduction in interleukin (IL)-6 and IL-1ß in lung tissue which are the proinflammatory cytokines. However, plasma IL-1ß and tissue tumor necrosis factor (TNF)-α level decrease (p = 0.24; p = 0.19) with this pretreatment. Further, ICAM-1 mRNA expression and nuclear factor (NF)-kappa B protein expression were significantly (p < 0.01) decreased in luteolin pretreated septic mice. The lung iNOS level, iNOS mRNA and protein expressions were markedly (p = 0.25; p = 0.50; p = 0.06) altered with luteolin pretreatment, respectively. Also, significant reduction in lipid peroxidation and increase in the activity of antioxidant enzymes like superoxide dismutase (SOD) and catalase was noted with luteolin pretreatment. However, luteolin did not alter (p = 0.36) the non enzymatic antioxidant GSH activity in septic mice. Histopathology of lung tissue showed reduction in lung injury with the luteolin pretreatment in septic mice. The study suggests that luteolin showed attenuation in sepsis-induced acute lung injury in mice through suppression in ICAM-1, NF-kappa B, oxidative stress and partially iNOS pathways.


Assuntos
Lesão Pulmonar Aguda/tratamento farmacológico , Pulmão/efeitos dos fármacos , Luteolina/farmacologia , Sepse/tratamento farmacológico , Lesão Pulmonar Aguda/metabolismo , Animais , Antioxidantes/metabolismo , Líquido da Lavagem Broncoalveolar , Catalase/metabolismo , Modelos Animais de Doenças , Molécula 1 de Adesão Intercelular/metabolismo , Interleucina-6/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Pulmão/metabolismo , Masculino , Camundongos , NF-kappa B/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Estresse Oxidativo/efeitos dos fármacos , RNA Mensageiro/metabolismo , Sepse/metabolismo , Superóxido Dismutase/metabolismo
8.
Exp Lung Res ; 44(2): 63-78, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29393707

RESUMO

AIM OF THE STUDY: Kaempferol is a flavonoid and important part of the diet. Kaempferol has shown antioxidant, antiinflammatory and antidiabetic activities in various studies. However, protective potential of kaempferol in acute lung injury induced by sepsis and its mechanism remains unclear. The present study was undertaken to evaluate the effect of kaempferol in sepsis-induced acute lung injury in mice and its possible mechanism of action. MATERIALS AND METHODS: Acute lung injury was induced by CLP surgery in mice. Kaempferol (100 mg/kg bw) was administered orally one hour before caecal ligation and puncture surgery in mice. Mice were divided into four groups sham, KEM+sham, sepsis (CLP), and KEM+sepsis. Assessment of lung injury was done by estimation of protein content in lung tissue, lung edema, proinflammatory cytokines in plasma and lung tissue, oxidative stress, antioxidant enzymes, nitrite production, and histopathology. RESULTS: Kaempferol pretreated mice showed significant (P < 0.001) decrease in water content in lungs. Kaempferol pretreatment showed reduction in cytokines IL-6, IL-1ß, and TNF-α in plasma as well as in lung tissue in comparison with septic mice without pretreatment. Pretreatment with kaempferol did not show any reduction in MDA level in comparison with septic mice. Antioxidant enzymes SOD and catalase and nonenzymatic antioxidant GSH activities were also increased with kaempferol pretreatment in septic mice. Further, kaempferol pretreatment reduced the lung tissue nitrite level (P < 0.01) and iNOS (P < 0.05) level in septic mice. A significant (P < 0.01) downregulation of mRNA expression of ICAM-1 and iNOS was observed with this pretreatment. Kaempferol pretreatment did not decrease bacterial load in septic mice. Mice pretreated with kaempferol followed by sepsis showed lesser infiltration of cells and more arranged alveolar structure in histopathological analysis. CONCLUSIONS: The study suggests that kaempferol showed attenuation in sepsis-induced acute lung injury in mice through suppression of oxidative stress, iNOS, and ICAM-1 pathways.


Assuntos
Lesão Pulmonar Aguda/tratamento farmacológico , Quempferóis/uso terapêutico , Sepse/complicações , Lesão Pulmonar Aguda/etiologia , Animais , Citocinas/metabolismo , Modelos Animais de Doenças , Molécula 1 de Adesão Intercelular/efeitos dos fármacos , Molécula 1 de Adesão Intercelular/metabolismo , Camundongos , Óxido Nítrico Sintase Tipo II/efeitos dos fármacos , Óxido Nítrico Sintase Tipo II/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Oxirredutases/efeitos dos fármacos , Oxirredutases/metabolismo , Substâncias Protetoras/uso terapêutico , Punções/efeitos adversos
9.
Chemistry ; 23(22): 5330-5337, 2017 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-28195373

RESUMO

The synthesis, photophysical properties and photocatalytic efficiency of a range of novel supramolecular assemblies of the type [Ru(dceb)2 (µ-bisbpy)MCl2 ][PF6 ]2 and [Ru(bpy)2 (µ-bisbpy)MCl2 ][PF6 ]2 (M=Pd or Pt, dceb=diethyl 2,2'-bipyridine-4,4'-dicarboxylate, bpy=2,2'-bipyridine and bisbpy=2,2':5',3'':6'',2'''-quaterpyridine) are reported. Photocatalytic hydrogen generation was dependent on the nature of the peripheral ligand, on the catalytic centre and on the amount of water present in the photocatalytic mixture. The best catalytic conditions were obtained with the dceb peripheral ligand (turnover numbers up to 513 after 18 h). The experimental data and DFT calculations on both the bpy- and dceb-based compounds indicated that the peripheral dceb ligands participated in the photocatalytic process.

10.
J Org Chem ; 82(4): 1996-2003, 2017 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-28112920

RESUMO

Here, we describe a photoredox-assisted catalytic system for the direct reductive coupling of two carbon electrophiles. Recent advances have shown that nickel catalysts are active toward the coupling of sp3-carbon electrophiles and that well-controlled, light-driven coupling systems are possible. Our system, composed of a nickel catalyst, an iridium photosensitizer, and an amine electron donor, is capable of coupling halocarbons with high yields. Spectroscopic studies support a mechanism where under visible light irradiation the Ir photosensitizer in conjunction with triethanolamine are capable of reducing a nickel catalyst and activating the catalyst toward cross-coupling of carbon electrophiles. The synthetic methodology developed here operates at low 1 mol % catalyst and photosensitizer loadings. The catalytic system also operates without reaction additives such as inorganic salts or bases. A general and effective sp2-sp3 cross-coupling scheme has been achieved that exhibits tolerance to a wide array of functional groups.

11.
Gen Comp Endocrinol ; 240: 198-213, 2017 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-27815159

RESUMO

The role of growth factors in the modulation of ovarian function is an interesting area of research in reproductive biology. Recently, we have shown the expression and role of IGF, EGF, VEGF and FGF in the follicle and CL. Here, we report the presence of Bone Morphogenetic Proteins (BMPs) and their functional receptors in the corpus luteum (CL) of buffalo. The bubaline CL was classified into four stages according to the morphology and progesterone (P4) concentration. The qPCR, immunoblot and immunohistochemistry studies revealed that BMP2 and BMP Receptors (BMPR1A, BMPR1B and BMPR2) were significantly upregulated during the mid stage whereas BMP4 and BMP7 were upregulated during the early stage of CL (P<0.05). Studies on primary luteal cell culture (LCC) using mid CL showed a significant time and concentration dependent effect of BMP4 and BMP7 (P<0.05). At 100ngml-1, the BMPs maximally stimulated the transcripts of StAR, CYP11A1 and 3ßHSD that paralleled with P4 accretion in the media (P<0.05). Further, the BMP4 as well as BMP7 upregulated the transcripts of PCNA and downregulated CASPASE3 in the LCC at the same concentration (P<0.05). Though the combined effect of BMP4 and 7 was significantly higher (P<0.05) than that of individual one, it was not additive. In conclusion, the expression of BMPs and their receptors were dependent on the stages of CL in the buffalo. Treatment of LCC with BMPs in vitro confirmed the presence of functional receptors that stimulated the P4 production and luteal cell survival. Moreover, the results support the concept that the upregulation of P4 and its biosynthetic pathway enzymes such as CYP11A1, StAR and 3ßHSD in the CL is likely due to the autocrine and /or paracrine effects of BMP4 and BMP7 under physiological milieu.


Assuntos
Proteínas Morfogenéticas Ósseas/genética , Búfalos/genética , Corpo Lúteo/metabolismo , Regulação da Expressão Gênica , Animais , Apoptose , Receptores de Proteínas Morfogenéticas Ósseas/metabolismo , Proteínas Morfogenéticas Ósseas/metabolismo , Caspase 3/genética , Caspase 3/metabolismo , Células Cultivadas , Feminino , Perfilação da Expressão Gênica , Immunoblotting , Imuno-Histoquímica , Progesterona/genética , Progesterona/metabolismo , Antígeno Nuclear de Célula em Proliferação/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fatores de Tempo
12.
Zygote ; 25(3): 313-320, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28592334

RESUMO

Oocyte-secreted factors (OSFs) play an important role in the acquisition of oocyte developmental competence through bidirectional cross-talk between oocyte and cumulus cells via gap junctions. Thus, the present study was designed to investigate the effect of two OSFs, growth differentiation factor 9 (GDF9) and bone morphogenetic protein 15 (BMP15), on the developmental competence of buffalo oocytes derived from two different follicle sizes. Cumulus-oocyte complexes (COCs) from large follicles (LF, >6 mm) or small follicles (SF, 0.05) between DOs and combination groups. Relative mRNA analysis revealed significantly higher (P > 0.05) expression of the cumulus cell marker genes EGFR, HAS2, and CD44 in LF-derived than SF-derived oocyte; the expression of these markers was significantly higher (P > 0.05) in DOs and combination groups, irrespective of the follicle size. These results suggested that LF-derived oocytes have a higher developmental competence than SF-derived oocytes and that supplementation of GDF9 and BMP15 modulates the developmental competence of buffalo oocytes by increasing the relative abundance of cumulus-enabling factors and thereby increasing cleavage and the quality of blastocyst production.


Assuntos
Proteína Morfogenética Óssea 15/farmacologia , Regulação da Expressão Gênica , Fator 9 de Diferenciação de Crescimento/farmacologia , Oócitos/crescimento & desenvolvimento , Oócitos/metabolismo , Animais , Biomarcadores , Blastocisto/fisiologia , Proteína Morfogenética Óssea 15/metabolismo , Búfalos , Receptores ErbB/genética , Feminino , Fertilização in vitro , Regulação da Expressão Gênica/efeitos dos fármacos , Marcadores Genéticos , Fator 9 de Diferenciação de Crescimento/metabolismo , Receptores de Hialuronatos/genética , Hialuronan Sintases/genética , Técnicas de Maturação in Vitro de Oócitos/métodos , Masculino , Oócitos/efeitos dos fármacos , Folículo Ovariano/citologia
13.
Asian-Australas J Anim Sci ; 30(2): 246-253, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27221251

RESUMO

OBJECTIVE: Present study explores the effect of hot summer period on the glycolytic rate of early post-mortem meat quality of Ghungroo and Large White Yorkshire (LWY) pig and comparative adaptability to high temperature between above breeds by shifting the expression of stress related genes like mono-carboxylate transporters (MCTs) and heat shock proteins (HSPs). METHODS: Healthy pigs of two different breeds, viz., LYW and Ghungroo (20 from each) were maintained during hot summer period (May to June) with a mean temperature of about 38°C. The pigs were slaughtered and meat samples from the longissimus dorsi (LD) muscles were analyzed for pH, glycogen and lactate content and mRNA expression. Following 24 h of chilling, LD muscle was also taken from the carcasses to evaluate protein solubility and different meat quality measurements. RESULTS: LWY exhibited significantly (p<0.01) higher plasma cortisol and lactate dehydrogenase concentration than Ghungroo indicating their higher sensitivity to high temperature. LD muscle from LWY pigs revealed lower initial and ultimate pH values and higher drip loss compared to Ghungroo, indicating a faster rate of pH fall. LD muscle of Ghungroo had significantly lower lactate content at 45 min postmortem indicating normal postmortem glycolysis and much slower glycolytic rate at early postmortem. LD muscle of LWY showed rapid postmortem glycolysis, higher drip loss and higher degrees of protein denaturation. Ghungroo exhibited slightly better water holding capacity, lower cooking loss and higher protein solubility. All HSPs (HSP27, HSP70, and HSP90) and MCTs (MCT1, MCT2, and MCT4) in the LD muscle of pigs inclined to increase more in Ghungroo than LWY when exposed to high temperature. CONCLUSION: Effect of high temperature on the variation of HSPs and MCTs may play a crucial role in thermal tolerance and adaptation to different climatic conditions, pH regulation, muscle acidification, drip loss, protein denaturation and also in postmortem meat quality development.

14.
Bioconjug Chem ; 27(1): 36-41, 2016 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-26619248

RESUMO

Photosynthesis is Nature's major process for converting solar into chemical energy. One of the key players in this process is the multiprotein complex photosystem I (PSI) that through absorption of incident photons enables electron transfer, which makes this protein attractive for applications in bioinspired photoactive hybrid materials. However, the efficiency of PSI is still limited by its poor absorption in the green part of the solar spectrum. Inspired by the existence of natural phycobilisome light-harvesting antennae, we have widened the absorption spectrum of PSI by covalent attachment of synthetic dyes to the protein backbone. Steady-state and time-resolved photoluminescence reveal that energy transfer occurs from these dyes to PSI. It is shown by oxygen-consumption measurements that subsequent charge generation is substantially enhanced under broad and narrow band excitation. Ultimately, surface photovoltage (SPV) experiments prove the enhanced activity of dye-modified PSI even in the solid state.


Assuntos
Corantes Fluorescentes/química , Compostos Heterocíclicos de 4 ou mais Anéis/química , Complexo de Proteína do Fotossistema I/química , Cianobactérias/química , Transferência de Energia , Transferência Ressonante de Energia de Fluorescência , Concentração de Íons de Hidrogênio , Luminescência , Lisina/química , Microscopia Eletrônica de Transmissão , Oxigênio/química , Oxigênio/metabolismo
15.
bioRxiv ; 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38645263

RESUMO

Single nucleus RNA sequencing (snRNA-seq), an alternative to single cell RNA sequencing (scRNA-seq), encounters technical challenges in obtaining high-quality nuclei and RNA, persistently hindering its applications. Here, we present a robust technique for isolating nuclei across various tissue types, remarkably enhancing snRNA-seq data quality. Employing this approach, we comprehensively characterize the depot-dependent cellular dynamics of various cell types underlying adipose tissue remodeling during obesity. By integrating bulk nuclear RNA-seq from adipocyte nuclei of different sizes, we identify distinct adipocyte subpopulations categorized by size and functionality. These subpopulations follow two divergent trajectories, adaptive and pathological, with their prevalence varying by depot. Specifically, we identify a key molecular feature of dysfunctional hypertrophic adipocytes, a global shutdown in gene expression, along with elevated stress and inflammatory responses. Furthermore, our differential gene expression analysis reveals distinct contributions of adipocyte subpopulations to the overall pathophysiology of adipose tissue. Our study establishes a robust snRNA-seq method, providing novel insights into the mechanisms orchestrating adipose tissue remodeling during obesity, with broader applicability across diverse biological systems.

16.
Inorg Chem ; 51(4): 1977-9, 2012 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-22296290

RESUMO

The effect of the water concentration on the quantitation of formate from dimethylformamide in the presence of electron-donating bases using ion chromatography is reported. This observation has important implications in the area of the photocatalytic reduction of CO(2), where formate levels are often used to calculate catalyst turnover numbers.

17.
Artigo em Inglês | MEDLINE | ID: mdl-35144941

RESUMO

INTRODUCTION: Inadequate glycemic control among patients with type 2 diabetes mellitus (T2DM) poses an enormous challenge. Whether this uncontrolled T2DM population is a heterogenous mix of disease subtypes remains unknown. Identification of these subtypes would result in a customized T2DM management protocol thereby paving the way toward personalized therapy. RESEARCH DESIGN AND METHODS: Electronic health records of 339 patients with uncontrolled T2DM patients followed up for a median period of 14 months were analyzed using Uniform Manifold Approximation and Projection followed by density-based spatial clustering of applications with noise. Baseline clinical features and final diagnoses with drug combinations were selected in the analysis. A 30 min oral glucose tolerance test was next performed for assessing the underlying insulin resistance and ß cell dysfunction. RESULTS: Three major clusters were identified. The first cluster characterized by recent onset T2DM had moderately preserved ß cell function. The second cluster with a longer duration of T2DM and associated hypertension showed the best glycemic control with dual antidiabetic therapy. The third cluster with the longest history of T2DM and no history of hypertension had the worst glycemic control in spite of the highest percentage of patients on triple therapy (34.58%) and quadruple therapy (8.41%). CONCLUSIONS: Uncontrolled T2DM comprises a heterogeneous population with respect to disease duration, presence of co-morbidities and ß cell function without significant difference in insulin resistance. Stratifying them on the basis of pathoclinical features is the first step toward a personalized management in T2DM.


Assuntos
Diabetes Mellitus Tipo 2 , Resistência à Insulina , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/epidemiologia , Humanos , Hipoglicemiantes/uso terapêutico , Índia/epidemiologia , Estudos Prospectivos
18.
Diabetes ; 71(11): 2284-2296, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-35899967

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is an independent predictor of systemic insulin resistance and type 2 diabetes mellitus (T2DM). However, converse correlates between excess liver fat content and ß-cell function remain equivocal. Specifically, how the accumulation of liver fat consequent to the enhanced de novo lipogenesis (DNL) leads to pancreatic ß-cell failure and eventually to T2DM is elusive. Here, we have identified that low-molecular-weight calcium-binding protein S100A6, or calcyclin, inhibits glucose-stimulated insulin secretion (GSIS) from ß cells through activation of the receptor for the advanced glycation end products and diminution of mitochondrial respiration. Serum S100A6 level is elevated both in human patients with NAFLD and in a high-fat diet-induced mouse model of NAFLD. Although serum S100A6 levels are negatively associated with ß-cell insulin secretory capacity in human patients, depletion of hepatic S100A6 improves GSIS and glycemia in mice, suggesting that S100A6 contributes to the pathophysiology of diabetes in NAFLD. Moreover, transcriptional induction of hepatic S100A6 is driven by the potent regulator of DNL, carbohydrate response element-binding protein (ChREBP), and ectopic expression of ChREBP in the liver suppresses GSIS in a S100A6-sensitive manner. Together, these data suggest elevated serum levels of S100A6 may serve as a biomarker in identifying patients with NAFLD with a heightened risk of developing ß-cell dysfunction. Overall, our data implicate S100A6 as, to our knowledge, a hitherto unknown hepatokine to be activated by ChREBP and that participates in the hepato-pancreatic communication to impair insulin secretion and drive the development of T2DM in NAFLD.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Proteína A6 Ligante de Cálcio S100 , Animais , Humanos , Camundongos , Glicemia/metabolismo , Proteínas de Ciclo Celular/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Produtos Finais de Glicação Avançada/metabolismo , Insulina/metabolismo , Resistência à Insulina/fisiologia , Lipogênese/fisiologia , Fígado/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Proteína A6 Ligante de Cálcio S100/metabolismo
19.
STAR Protoc ; 2(4): 101027, 2021 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-34977673

RESUMO

Here, we describe a robust protocol using mouse models to screen potential insulin-stabilizers and insulin moieties. We have generated a mouse model of amyloidoma, found in diabetic patients undergoing insulin therapy. This model can be used to screen potential insulin stabilizers and insulin moieties to prevent amyloidoma formation. This protocol can further be used for the preclinical validation of therapeutically relevant insulin stabilizers and formulations. The protocol highlights all the critical steps for generating amyloidoma in a preclinical model. For complete details on the use and execution of this profile, please refer to Mukherjee et al. (2021).


Assuntos
Amiloide , Amiloidose , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos/métodos , Amiloide/química , Amiloide/efeitos dos fármacos , Amiloide/metabolismo , Amiloidose/metabolismo , Amiloidose/patologia , Animais , Insulina/química , Insulina/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C
20.
Chem Sci ; 12(14): 5082-5090, 2021 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-34163748

RESUMO

The enhancement of reactivity inside supramolecular coordination cages has many analogies to the mode of action of enzymes, and continues to inspire the design of new catalysts for a range of reactions. However, despite being a near-ubiquitous class of reactions in organic chemistry, enhancement of the reduction of carbonyls to their corresponding alcohols remains very much underexplored in supramolecular coordination cages. Herein, we show that encapsulation of small aromatic aldehydes inside a supramolecular coordination cage allows the reduction of these aldehydes with the mild reducing agent sodium cyanoborohydride to proceed with high selectivity (ketones and esters are not reduced) and in good yields. In the absence of the cage, low pH conditions are essential for any appreciable conversion of the aldehydes to the alcohols. In contrast, the specific microenvironment inside the cage allows this reaction to proceed in bulk solution that is pH-neutral, or even basic. We propose that the cage acts to stabilise the protonated oxocarbenium ion reaction intermediates (enhancing aldehyde reactivity) whilst simultaneously favouring the encapsulation and reduction of smaller aldehydes (which fit more easily inside the cage). Such dual action (enhancement of reactivity and size-selectivity) is reminiscent of the mode of operation of natural enzymes and highlights the tremendous promise of cage architectures as selective catalysts.

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