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1.
Atherosclerosis ; : 117518, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38627162

RESUMO

BACKGROUND AND AIMS: There are a limited number of pharmacologic therapies for coronary artery disease, and few rodent models of occlusive coronary atherosclerosis and consequent myocardial infarction with which one can rapidly test new therapeutic approaches. Here, we characterize a novel, fertile, and easy-to-use HDL receptor (SR-B1)-based model of atherogenic diet-inducible, fatal coronary atherosclerosis, the SR-B1ΔCT/LDLR KO mouse. Additionally, we test intramyocardial injection of Stromal Cell-Derived Factor-1 alpha (SDF-1α), a potent angiogenic cytokine, as a possible therapy to rescue cardiac function in this mouse. METHODS: SR-B1ΔCT/LDLR KO mice were fed the Paigen diet or standard chow diet, and we determined the effects of the diets on cardiac function, histology, and survival. After two weeks of feeding either the Paigen diet (n = 24) or standard chow diet (n = 20), the mice received an intramyocardial injection of either SDF-1α or phosphate buffered saline (PBS). Cardiac function and angiogenesis were assessed two weeks later. RESULTS: When six-week-old mice were fed the Paigen diet, they began to die as early as 19 days later and 50% had died by 38 days. None of the mice maintained on the standard chow diet died by day 72. Hearts from mice on the Paigen diet showed evidence of cardiomegaly, myocardial infarction, and occlusive coronary artery disease. For the five mice that survived until day 28 that underwent an intramyocardial injection of PBS on day 15, the average ejection fraction (EF) decreased significantly from day 14 (the day before injection, 52.1 ± 4.3%) to day 28 (13 days after the injection, 30.6 ± 6.8%) (paired t-test, n = 5, p = 0.0008). Of the 11 mice fed the Paigen diet and injected with SDF-1α on day 15, 8 (72.7%) survived to day 28. The average EF for these 8 mice increased significantly from 48.2 ± 7.2% on day 14 to63.6 ± 6.9% on day 28 (Paired t-test, n = 8, p = 0.003). CONCLUSIONS: This new mouse model and treatment with the promising angiogenic cytokine SDF-1α may lead to new therapeutic approaches for ischemic heart disease.

3.
Nutrients ; 16(3)2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38337692

RESUMO

We previously demonstrated a beneficial effect of high-dose vitamin D in pregnancy on offspring bone and dental health. Here, we investigated the effect of maternal dietary patterns during pregnancy on the risk of bone fractures, bone mineralization and enamel defects until age 6 years in the offspring. Further, the influence of diet on the effect of high-dose vitamin D was analyzed in the COPSAC2010 mother-child cohort including 623 mother-child pairs. A weighted network analysis on FFQs revealed three specific maternal dietary patterns that associated (Bonferroni p < 0.05) with both offspring bone and dental health. The effect of prenatal high-dose (2800 IU/day) vs. standard-dose (400 IU/day) vitamin D on offspring bone mineral content (adjusted mean difference (aMD): 33.29 g, 95% CI: 14.48-52.09, p < 0.001), bone mineral density (aMD: 0.02 g/cm2 (0.01-0.04), p < 0.001), fracture risk (adjusted incidence rate ratio: 0.36 (0.16-0.84), p = 0.02), and enamel defects in primary (adjusted odds ratio (aOR): 0.13 (0.03-0.58), p < 0.01) and permanent molars (aOR: 0.25; (0.10-0.63), p < 0.01) was most pronounced when mothers had lower intake of fruit, vegetables, meat, eggs, sweets, whole grain, offal and fish. This study suggests that prenatal dietary patterns influence offspring bone and dental development, and should be considered in order to obtain the full benefits of vitamin D to enhance personalized supplementation strategy.


Assuntos
Fraturas Ósseas , Vitamina D , Gravidez , Feminino , Animais , Humanos , Criança , Calcificação Fisiológica , Dieta , Vitaminas/farmacologia , Fraturas Ósseas/epidemiologia , Fraturas Ósseas/etiologia , Fraturas Ósseas/prevenção & controle , Densidade Óssea , Suplementos Nutricionais , Esmalte Dentário
4.
Commun Biol ; 7(1): 111, 2024 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-38243071

RESUMO

Glutamine synthetases (GS) catalyze the ATP-dependent ammonium assimilation, the initial step of nitrogen acquisition that must be under tight control to fit cellular needs. While their catalytic mechanisms and regulations are well-characterized in bacteria and eukaryotes, only limited knowledge exists in archaea. Here, we solved two archaeal GS structures and unveiled unexpected differences in their regulatory mechanisms. GS from Methanothermococcus thermolithotrophicus is inactive in its resting state and switched on by 2-oxoglutarate, a sensor of cellular nitrogen deficiency. The enzyme activation overlays remarkably well with the reported cellular concentration for 2-oxoglutarate. Its binding to an allosteric pocket reconfigures the active site through long-range conformational changes. The homolog from Methermicoccus shengliensis does not harbor the 2-oxoglutarate binding motif and, consequently, is 2-oxoglutarate insensitive. Instead, it is directly feedback-inhibited through glutamine recognition by the catalytic Asp50'-loop, a mechanism common to bacterial homologs, but absent in M. thermolithotrophicus due to residue substitution. Analyses of residue conservation in archaeal GS suggest that both regulations are widespread and not mutually exclusive. While the effectors and their binding sites are surprisingly different, the molecular mechanisms underlying their mode of action on GS activity operate on the same molecular determinants in the active site.


Assuntos
Archaea , Glutamina , Glutamina/metabolismo , Archaea/genética , Archaea/metabolismo , Glutamato-Amônia Ligase/metabolismo , Ácidos Cetoglutáricos , Bactérias/metabolismo , Nitrogênio/metabolismo
5.
Afr J Reprod Health ; 27(12): 79-85, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-38158865

RESUMO

This study assesses the risk that rape survivors have of developing cervical cancer in the context of conflict. A cross-sectional and descriptive study conducted in Bunyakiri and Kavumu, a conflict region in the east of the Democratic Republic of the Congo during the period from September 1 to 10, 2022, including 47 women survivors of sexual violence, 41 of whom were selected on the basis of certain criteria with age ranging from 18 to 50 years. Speculum examination was performed with visual inspection with acetic acid (VIA). After collecting data, the latter were encoded in the Excel file and grouped in the form of tables then analyzed after calculating the percentage. Ages of 21-30 years was the most represented, i.e., 56%. Among them, 34.1% were married and 31.7% were abandoned. Majority was in secondary school (46.3%) and illiterates (34.1%). 36.5% complained of pelvic pain and 36.5% reported first sexual intercourse at the age range of 13-15 years, of which 25 cases, i.e., 61% were sexually active. 39% reported having had 3 sexual partners in their life. VIA was negative in 97.5% of cases. It should be mentioned in this study that the environment of conflict zone, the circumstances of rape and the risky sexual behavior of survivors are an ecosystem that predisposes them to cervical cancer.


Cette étude évalue le risque qu'ont les survivantes de viol de développer un cancer du col de l'utérus dans un contexte de conflit. Une étude transversale et descriptive menée à Bunyakiri et Kavumu, région de conflit à l'est de la République Démocratique du Congo durant la période du 1er au 10 septembre 2022, incluant 47 femmes survivantes de violences sexuelles, dont 41 ont été sélectionnées sur la base de certains critères avec un âge allant de 18 à 50 ans. L'examen au spéculum a été réalisé avec inspection visuelle à l'acide acétique (VIA). Après collecte des données, ces dernières ont été encodées dans le fichier Excel et regroupées sous forme de tableaux puis analysées après calcul du pourcentage. La tranche d'âge de 21 à 30 ans était la plus représentée, soit 56 %. Parmi eux, 34,1% étaient mariés et 31,7% étaient abandonnés. La majorité était scolarisée dans le secondaire (46,3%) et analphabète (34,1%). 36,5% se plaignaient de douleurs pelviennes et 36,5% rapportaient leurs premiers rapports sexuels entre 13 et 15 ans, dont 25 cas, soit 61% étaient sexuellement actifs. 39 % déclarent avoir eu 3 partenaires sexuels dans leur vie. VIA était négatif dans 97,5 % des cas. Il convient de mentionner dans cette étude que l'environnement de la zone de conflit, les circonstances du viol et le comportement sexuel à risque des survivantes constituent un écosystème qui les prédispose au cancer du col de l'utérus.


Assuntos
Estupro , Delitos Sexuais , Neoplasias do Colo do Útero , Humanos , Feminino , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/epidemiologia , República Democrática do Congo/epidemiologia , Estudos Transversais , Ecossistema , Guerra , Detecção Precoce de Câncer , Ácido Acético , Sobreviventes , Fatores de Risco
6.
Angew Chem Int Ed Engl ; 62(45): e202311981, 2023 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-37712590

RESUMO

Massive efforts are invested in developing innovative CO2 -sequestration strategies to counter climate change and transform CO2 into higher-value products. CO2 -capture by reduction is a chemical challenge, and attention is turned toward biological systems that selectively and efficiently catalyse this reaction under mild conditions and in aqueous solvents. While a few reports have evaluated the effectiveness of isolated bacterial formate dehydrogenases as catalysts for the reversible electrochemical reduction of CO2 , it is imperative to explore other enzymes among the natural reservoir of potential models that might exhibit higher turnover rates or preferential directionality for the reductive reaction. Here, we present electroenzymatic catalysis of formylmethanofuran dehydrogenase, a CO2 -reducing-and-fixing biomachinery isolated from a thermophilic methanogen, which was deposited on a graphite rod electrode to enable direct electron transfer for electroenzymatic CO2 reduction. The gas is reduced with a high Faradaic efficiency (109±1 %), where a low affinity for formate prevents its electrochemical reoxidation and favours formate accumulation. These properties make the enzyme an excellent tool for electroenzymatic CO2 -fixation and inspiration for protein engineering that would be beneficial for biotechnological purposes to convert the greenhouse gas into stable formate that can subsequently be safely stored, transported, and used for power generation without energy loss.


Assuntos
Dióxido de Carbono , Formiato Desidrogenases , Dióxido de Carbono/química , Oxirredução , Catálise , Formiato Desidrogenases/metabolismo , Formiatos/metabolismo
8.
Front Microbiol ; 14: 1179204, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37250035

RESUMO

Whilst widespread in the microbial world, the hybrid cluster protein (HCP) has been paradoxically a long-time riddle for microbiologists. During three decades, numerous studies on a few model organisms unravelled its structure and dissected its metal-containing catalyst, but the physiological function of the enzyme remained elusive. Recent studies on bacteria point towards a nitric oxide reductase activity involved in resistance during nitrate and nitrite reduction as well as host infection. In this study, we isolated and characterised a naturally highly produced HCP class I from a marine methanogenic archaeon grown on ammonia. The crystal structures of the enzyme in a reduced and partially oxidised state, obtained at a resolution of 1.45 and 1.36-Å, respectively, offered a precise picture of the archaeal enzyme intimacy. There are striking similarities with the well-studied enzymes from Desulfovibrio species regarding sequence, kinetic parameters, structure, catalyst conformations, and internal channelling systems. The close phylogenetic relationship between the enzymes from Methanococcales and many Bacteria corroborates this similarity. Indeed, Methanococcales HCPs are closer to these bacterial homologues than to any other archaeal enzymes. The relatively high constitutive production of HCP in M. thermolithotrophicus, in the absence of a notable nitric oxide source, questions the physiological function of the enzyme in these ancient anaerobes.

9.
Genome Biol ; 24(1): 55, 2023 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-36964601

RESUMO

BACKGROUND: Transcription bridges genetic information and phenotypes. Here, we evaluated how changes in transcriptional regulation enable maize (Zea mays), a crop originally domesticated in the tropics, to adapt to temperate environments. RESULT: We generated 572 unique RNA-seq datasets from the roots of 340 maize genotypes. Genes involved in core processes such as cell division, chromosome organization and cytoskeleton organization showed lower heritability of gene expression, while genes involved in anti-oxidation activity exhibited higher expression heritability. An expression genome-wide association study (eGWAS) identified 19,602 expression quantitative trait loci (eQTLs) associated with the expression of 11,444 genes. A GWAS for alternative splicing identified 49,897 splicing QTLs (sQTLs) for 7614 genes. Genes harboring both cis-eQTLs and cis-sQTLs in linkage disequilibrium were disproportionately likely to encode transcription factors or were annotated as responding to one or more stresses. Independent component analysis of gene expression data identified loci regulating co-expression modules involved in oxidation reduction, response to water deprivation, plastid biogenesis, protein biogenesis, and plant-pathogen interaction. Several genes involved in cell proliferation, flower development, DNA replication, and gene silencing showed lower gene expression variation explained by genetic factors between temperate and tropical maize lines. A GWAS of 27 previously published phenotypes identified several candidate genes overlapping with genomic intervals showing signatures of selection during adaptation to temperate environments. CONCLUSION: Our results illustrate how maize transcriptional regulatory networks enable changes in transcriptional regulation to adapt to temperate regions.


Assuntos
Transcriptoma , Zea mays , Estudo de Associação Genômica Ampla , Locos de Características Quantitativas , Fenótipo , Polimorfismo de Nucleotídeo Único
10.
Cancers (Basel) ; 15(4)2023 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-36831393

RESUMO

Prostate cancer is the most common malignant tumour in men. Improved testing for diagnosis, risk prediction, and response to treatment would improve care. Here, we identified a proteomic signature of prostate cancer in peripheral blood using data-independent acquisition mass spectrometry combined with machine learning. A highly predictive signature was derived, which was associated with relevant pathways, including the coagulation, complement, and clotting cascades, as well as plasma lipoprotein particle remodeling. We further validated the identified biomarkers against a second cohort, identifying a panel of five key markers (GP5, SERPINA5, ECM1, IGHG1, and THBS1) which retained most of the diagnostic power of the overall dataset, achieving an AUC of 0.91. Taken together, this study provides a proteomic signature complementary to PSA for the diagnosis of patients with localised prostate cancer, with the further potential for assessing risk of future development of prostate cancer. Data are available via ProteomeXchange with identifier PXD025484.

11.
Rev Neurol (Paris) ; 178(10): 1079-1089, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36336491

RESUMO

BACKGROUND: Intravenous thrombolysis (IVT) use for acute ischemic stroke (AIS) varies among countries, partly due to guidelines and product labeling changes. The study aim was to identify the characteristics of patients with AIS treated with off-label IVT and to determine its safety when performed in a primary stroke center (PSC). METHODS: This observational, single-center study included all consecutive patients admitted to Perpignan PSC for AIS and treated with IVT and patients transferred for EVT, between January 1, 2015 and December 31, 2019. Data of patients treated with IVT according to ("in-label group") or outside ("off-label") the initial guidelines and manufacturer's product specification were compared. Safety was assessed using symptomatic intracerebral hemorrhage (SIH) as the main adverse event. RESULTS: Among the 892 patients in the database (834 screened by MRI, 93.5%), 746 were treated by IVT: 185 (24.8%) "in-label" and 561 (75.2%) "off-label". In the "off-label" group, 316 (42.4% of the cohort) had a single criterion for "off-label" use, 197 (26.4%) had two, and 48 (6.4%) had three or more criteria, without any difference in IVT safety pattern among them. SIH rates were comparable between the "off-label" and "in-label" groups (2.7% vs. 1.1%, P=0.21); early neurological deterioration and systematic adverse event due to IVT treatment were similar in the 2 groups. "Off-label" patients had higher in-hospital (8.7% vs. 3.8%, P=0.05) and 3-month mortality rates (12.1% vs 5.4%, P<0.01), but this is explained by confounding factors as they were older (76 vs 67 years, P<0.0001) and more dependent (median modified Rankin scale score 0.4 vs 0.1, P<0.0001) at admission. CONCLUSIONS: "Off-label" thrombolysis for AIS seems to be safe and effective in the routine setting of a primary stroke center.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Terapia Trombolítica/efeitos adversos , Fibrinolíticos/efeitos adversos , Isquemia Encefálica/tratamento farmacológico , Estudos Retrospectivos , AVC Isquêmico/etiologia , Acidente Vascular Cerebral/terapia , Hemorragia Cerebral/induzido quimicamente , Hemorragia Cerebral/epidemiologia , Hemorragia Cerebral/tratamento farmacológico , Resultado do Tratamento
12.
Mar Pollut Bull ; 184: 114180, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36183511

RESUMO

Deep-sea ecosystems play a key role in the cycling and vertical transfer of matter and energy in oceans. Although the contamination of deep-sea demersal and benthic organisms by persistent organic pollutants has been proven, deep pelagic species have been far less studied. To fill these gaps, we studied the occurrence of a large variety of hydrophobic organic contaminants including polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), legacy and alternative brominated flame retardants (BFRs) and per- and polyfluoroalkyl substances (PFASs) in crustaceans and fish species collected in the Bay of Biscay, northeast Atlantic. The results highlighted the global predominance of PCBs in fish, followed by OCPs, PFASs and PBDEs, with highly variable concentrations among species. Most of the chlorinated or brominated contaminants showed increasing concentrations with increasing δ15N values, while most PFASs showed inverse trends. The contaminant profiles and diagnostic ratios revealed species-specific metabolic capacities and peculiar contribution of highly-brominated BFRs.


Assuntos
Retardadores de Chama , Fluorocarbonos , Hidrocarbonetos Clorados , Praguicidas , Bifenilos Policlorados , Animais , Bifenilos Policlorados/análise , Retardadores de Chama/análise , Éteres Difenil Halogenados/metabolismo , Ecossistema , Poluentes Orgânicos Persistentes , Baías , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Peixes/metabolismo , Monitoramento Ambiental
14.
J Neurol ; 269(9): 4972-4984, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35752990

RESUMO

OBJECTIVE: Cerebral amyloid angiopathy-related inflammation (CAA-ri) is a rare manifestation related to CAA, thought to be more severe. We aimed to compare the clinical and radiological outcomes of CAA-ri and non-inflammatory CAA. MATERIALS AND METHODS: We retrospectively included all patients with CAA-ri from 13 French centers. We constituted a sex- and age-matched control cohort with non-inflammatory CAA and similar disease duration. Survival, autonomy and cognitive evolution were compared after logistic regression. Cerebral microbleeds (CMB), intracerebral hemorrhage, cortical superficial siderosis and hippocampal atrophy were analyzed as well as CSF biomarker profile and APOE genotype when available. Outcomes were compared using Kaplan-Meier curves and log-rank tests. RESULTS: Data from 48 CAA-ri patients including 28 already reported and 20 new patients were analyzed. Over a mean of 3.1 years, 11 patients died (22.9%) and 18 (37.5%) relapsed. CAA-ri patients were more frequently institutionalized than non-inflammatory CAA patients (30% vs 8.3%, p < 0.001); mortality rates remained similar. MMSE and modified Rankin scale scores showed greater severity in CAA-ri at last follow-up. MRI showed a higher number of CMB at baseline and last follow-up in CAA-ri (p < 0.001 and p = 0.004, respectively). CSF showed lower baseline levels of Aß42 in CAA-ri than non-inflammatory CAA (373.3 pg/ml vs 490.8 pg/ml, p = 0.05). CAA-ri patients more likely carried at least one APOE ε4 allele (76% vs 37.5%, adjusted p = 0.05) particularly as homozygous status (56% vs 6.2%, p < 0.001). INTERPRETATION: CAA-ri appears to be more severe than non-inflammatory CAA with a significant loss of autonomy and global higher amyloid burden, shown by more CMB and a distinct CSF profile. This burden may be partially promoted by ε4 allele.


Assuntos
Angiopatia Amiloide Cerebral , Angiopatia Amiloide Cerebral/complicações , Angiopatia Amiloide Cerebral/diagnóstico por imagem , Hemorragia Cerebral/diagnóstico por imagem , Hemorragia Cerebral/etiologia , Humanos , Inflamação , Imageamento por Ressonância Magnética , Estudos Retrospectivos
15.
Biochemistry ; 61(10): 805-821, 2022 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-35500274

RESUMO

Microbial anaerobic oxidation of alkanes intrigues the scientific community by way of its impact on the global carbon cycle, and its biotechnological applications. Archaea are proposed to degrade short- and long-chain alkanes to CO2 by reversing methanogenesis, a theoretically reversible process. The pathway would start with alkane activation, an endergonic step catalyzed by methyl-coenzyme M reductase (MCR) homologues that would generate alkyl-thiols carried by coenzyme M. While the methane-generating MCR found in methanogens has been well characterized, the enzymatic activity of the putative alkane-fixing counterparts has not been validated so far. Such an absence of biochemical investigations contrasts with the current explosion of metagenomics data, which draws new potential alkane-oxidizing pathways in various archaeal phyla. Therefore, validating the physiological function of these putative alkane-fixing machines and investigating how their structures, catalytic mechanisms, and cofactors vary depending on the targeted alkane have become urgent needs. The first structural insights into the methane- and ethane-capturing MCRs highlighted unsuspected differences and proposed some explanations for their substrate specificity. This Perspective reviews the current physiological, biochemical, and structural knowledge of alkyl-CoM reductases and offers fresh ideas about the expected mechanistic and chemical differences among members of this broad family. We conclude with the challenges of the investigation of these particular enzymes, which might one day generate biofuels for our modern society.


Assuntos
Alcanos , Archaea , Alcanos/metabolismo , Anaerobiose , Archaea/química , Catálise , Mesna/metabolismo , Metano/metabolismo , Oxirredução , Oxirredutases/metabolismo , Filogenia
16.
Rev Neurol (Paris) ; 178(4): 377-384, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34556344

RESUMO

INTRODUCTION: Converting a high-volume primary stroke center (PSC) into a stroke center that can perform emergency endovascular treatment (EVT) could reduce the time to thrombectomy. We report the first results of a newly established EVT facility at the Perpignan PSC and their comparison with the targets defined by the established guidelines. PATIENTS AND METHOD: For this comprehensive observational study, data of patients with acute ischemic stroke (AIS) due to proximal large vessel occlusion (LVO) and treated by EVT at the Perpignan PSC from December 5, 2019 to September 15, 2020 were extracted from an ongoing prospective database. RESULTS: During the study period, 37 patients underwent EVT at the Perpignan PSC. The median (range) symptom-onset to recanalization time was 262min (100-485min). The median (range) intra-hospital times were: 20min (2-58min) for door-to-imaging, 57min (30-155min) for imaging-to-puncture, 55min (15-180min) for puncture-to-recanalization, and 137min (59-319min) for door-to-recanalization. At 3 months post-AIS, the favorable outcome (modified Ranking Score: 0-2) rate was 50% and the mortality rate was 19.4%. These results are comparable to those of previous clinical trials, and meet the targets defined by the current consensus statements for EVT. DISCUSSION AND CONCLUSION: Our results show the feasibility and safety of EVT in a PSC for patients with AIS due to LVO. The implementation of this strategy may be important for shortening the time to thrombectomy.


Assuntos
Isquemia Encefálica , Procedimentos Endovasculares , AVC Isquêmico , Acidente Vascular Cerebral , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/cirurgia , Procedimentos Endovasculares/métodos , Humanos , Estudos Retrospectivos , Acidente Vascular Cerebral/cirurgia , Trombectomia/métodos , Tempo para o Tratamento , Resultado do Tratamento
17.
Sci Adv ; 7(51): eabj6565, 2021 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-34910518

RESUMO

Stretchable optoelectronics made of elastomeric semiconductors could enable the integration of intelligent systems with soft materials, such as those of the biological world. Organic semiconductors and photodiodes have been engineered to be elastomeric; however, for photodetector applications, it remains a challenge to identify an elastomeric bulk heterojunction (e-BHJ) photoactive layer that combines a low Young's modulus and a high strain at break that yields organic photodiodes with low electronic noise values and high photodetector performance. Here, a blend of an elastomer, a donor-like polymer, and an acceptor-like molecule yields a skin-like e-BHJ with a Young's modulus of a few megapascals, comparable to values of human tissues, and a high strain at break of 189%. Elastomeric organic photodiodes based on e-BHJ photoactive layers maintain low electronic noise current values in the tens of femtoamperes range and noise equivalent power values in the tens of picowatts range under at least 60% strain.

18.
J Exp Clin Cancer Res ; 40(1): 355, 2021 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-34753495

RESUMO

The hopeful outcomes from 30 years of research in BH3-mimetics have indeed served a number of solid paradigms for targeting intermediates from the apoptosis pathway in a variety of diseased states. Not only have such rational approaches in drug design yielded several key therapeutics, such outputs have also offered insights into the integrated mechanistic aspects of basic and clinical research at the genetics level for the future. In no other area of medical research have the effects of such work been felt, than in cancer research, through targeting the BAX-Bcl-2 protein-protein interactions. With these promising outputs in mind, several mimetics, and their potential therapeutic applications, have also been developed for several other pathological conditions, such as cardiovascular disease and tissue fibrosis, thus highlighting the universal importance of the intrinsic arm of the apoptosis pathway and its input to general tissue homeostasis. Considering such recent developments, and in a field that has generated so much scientific interest, we take stock of how the broadening area of BH3-mimetics has developed and diversified, with a focus on their uses in single and combined cancer treatment regimens and recently explored therapeutic delivery methods that may aid the development of future therapeutics of this nature.


Assuntos
Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Neoplasias/terapia , Humanos , Modelos Moleculares
19.
Science ; 373(6550): 118-121, 2021 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-34210888

RESUMO

Ethane, the second most abundant hydrocarbon gas in the seafloor, is efficiently oxidized by anaerobic archaea in syntrophy with sulfate-reducing bacteria. Here, we report the 0.99-angstrom-resolution structure of the proposed ethane-activating enzyme and describe the specific traits that distinguish it from methane-generating and -consuming methyl-coenzyme M reductases. The widened catalytic chamber, harboring a dimethylated nickel-containing F430 cofactor, would adapt the chemistry of methyl-coenzyme M reductases for a two-carbon substrate. A sulfur from methionine replaces the oxygen from a canonical glutamine as the nickel lower-axial ligand, a feature conserved in thermophilic ethanotrophs. Specific loop extensions, a four-helix bundle dilatation, and posttranslational methylations result in the formation of a 33-angstrom-long hydrophobic tunnel, which guides the ethane to the buried active site as confirmed with xenon pressurization experiments.


Assuntos
Proteínas Arqueais/química , Etano/química , Methanosarcinales/enzimologia , Oxirredutases/química , Cristalografia por Raios X , Ativação Enzimática , Sequências Hélice-Alça-Hélice , Metilação , Processamento de Proteína Pós-Traducional
20.
J Vet Intern Med ; 35(4): 1720-1728, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34114259

RESUMO

BACKGROUND: Desoxycorticosterone pivalate (DOCP) is a commonly used mineralocorticoid replacement for dogs with primary hypoadrenocorticism (HA), but manufacturer-recommended dosing protocols can be cost-prohibitive. Recent reports also have raised concerns that label dose protocols could be excessive. OBJECTIVE: To investigate the relative efficacy and adverse effects of 2 DOCP dosages in dogs with primary glucocorticoid and mineralocorticoid deficient HA. ANIMALS: Thirty-seven dogs, including 19 test population dogs and 18 controls. METHODS: Randomized controlled double-blinded clinical trial. Dogs with newly diagnosed primary HA were assigned to standard (2.2 mg/kg q30d, control population) or low-dose (1.1 mg/kg q30d, test population) DOCP treatment. Clinical and laboratory variables were assessed 10 to 14 days and approximately 30 days after each DOCP treatment for 90 days. RESULTS: Mean serum sodium to potassium ratios at reevaluations were ≥32 in both populations throughout the study. No dog developed electrolyte abnormalities warranting medical treatment, although hypokalemia occurred on at least 1 occasion in 9 controls and 6 test population dogs. Urine specific gravities (median, interquartile range) were lower in control dogs (1.022, 1.016-1.029) as compared to test population dogs (1.033, 1.023-1.039; P = .006). Plasma renin activity was overly suppressed on 84 of 104 (80.8%) assessments in control dogs whereas increased renin activity occurred on 23 of 112 (20.5%) assessments in test population dogs. CONCLUSIONS AND CLINICAL IMPORTANCE: Low-dose DOCP protocols appear to be safe and effective for treatment of HA in most dogs. Standard-dose protocols are more likely to result in biochemical evidence of overtreatment.


Assuntos
Insuficiência Adrenal , Doenças do Cão , Insuficiência Adrenal/veterinária , Animais , Desoxicorticosterona/efeitos adversos , Desoxicorticosterona/análogos & derivados , Doenças do Cão/tratamento farmacológico , Cães , Mineralocorticoides/uso terapêutico
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