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1.
J Cell Physiol ; 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38770789

RESUMO

The sorting and assembly machinery (SAM) Complex is responsible for assembling ß-barrel proteins in the mitochondrial membrane. Comprising three subunits, Sam35, Sam37, and Sam50, the SAM complex connects the inner and outer mitochondrial membranes by interacting with the mitochondrial contact site and cristae organizing system complex. Sam50, in particular, stabilizes the mitochondrial intermembrane space bridging (MIB) complex, which is crucial for protein transport, respiratory chain complex assembly, and regulation of cristae integrity. While the role of Sam50 in mitochondrial structure and metabolism in skeletal muscle remains unclear, this study aims to investigate its impact. Serial block-face-scanning electron microscopy and computer-assisted 3D renderings were employed to compare mitochondrial structure and networking in Sam50-deficient myotubes from mice and humans with wild-type (WT) myotubes. Furthermore, autophagosome 3D structure was assessed in human myotubes. Mitochondrial metabolic phenotypes were assessed using Gas Chromatography-Mass Spectrometry-based metabolomics to explore differential changes in WT and Sam50-deficient myotubes. The results revealed increased mitochondrial fragmentation and autophagosome formation in Sam50-deficient myotubes compared to controls. Metabolomic analysis indicated elevated metabolism of propanoate and several amino acids, including ß-Alanine, phenylalanine, and tyrosine, along with increased amino acid and fatty acid metabolism in Sam50-deficient myotubes. Furthermore, impairment of oxidative capacity was observed upon Sam50 ablation in both murine and human myotubes, as measured with the XF24 Seahorse Analyzer. Collectively, these findings support the critical role of Sam50 in establishing and maintaining mitochondrial integrity, cristae structure, and mitochondrial metabolism. By elucidating the impact of Sam50-deficiency, this study enhances our understanding of mitochondrial function in skeletal muscle.

2.
Proc Biol Sci ; 288(1950): 20203020, 2021 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-33947235

RESUMO

Global change is altering ecosystems at an unprecedented rate. The resulting shifts in species ranges and reproductive timing are opening the potential for hybridization between closely related species which could dramatically alter the genetic diversity, adaptive capacity and evolutionary trajectory of interbreeding taxa. Here, we used behavioural breeding experiments, in vitro fertilization experiments, and whole-transcriptome gene expression data to assess the potential for and consequences of hybridization between Chinook and Coho salmon. We show that behavioural and gametic prezygotic barriers between socio-economically valuable Chinook and Coho salmon are incomplete. Postzygotically, we demonstrate a clear transcriptomic response to hybridization among F1 Chinook-Coho offspring. Genes transgressively expressed within hybrids were significantly enriched with genes encoded in the nucleus but localized to the mitochondrion, suggesting a potential role for mito-nuclear incompatibilities as a postzygotic mechanism of hybrid breakdown. Chinook and Coho salmon are expected to continue to respond to climate change with shifts in migration timing and habitat use, potentiating hybridization between these species. The downstream consequences of hybridization on the future of these threatened salmon, and the ecosystems they inhabit, is unknown.


Assuntos
Isolamento Reprodutivo , Salmão , Animais , Ecossistema , Hibridização Genética , Salmão/genética , Transcriptoma
3.
Sex Transm Dis ; 48(1): 37-41, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32932385

RESUMO

BACKGROUND: There is a paucity of population-based data on chlamydia in pregnancy despite rising rates in US women. Our objectives were to assess chlamydia prevalence by age group and to identify factors associated with infection in pregnant women to inform screening guidelines. METHODS: This cross-sectional study included pregnant women tested for chlamydia who delivered at the University of Alabama at Birmingham between November 1, 2012, and December 31, 2017. The primary outcome was chlamydia prevalence, defined as a positive urogenital chlamydia nucleic acid amplification test result documented in the electronic medical record. Multivariable logistic regression was used to identify factors associated with infection. RESULTS: Among 17,796 women who delivered during the study period, 13,657 (77%) had chlamydia testing performed at the University of Alabama at Birmingham. Chlamydia prevalence (95% confidence interval) was 7.4% (7.0%-7.9%). Age-stratified prevalence rates were 14.6%, 4.3%, and 1.7% for women younger than 25 years, 25 to 29 years, and 30 years or older, respectively. Chlamydia in pregnancy remained strongly associated with age (adjusted odds ratio [95% confidence interval], 7.2 [5.6-9.2] for age <25 years, and 2.3 [1.7-3.0] for ages 25-29 years, when compared with >30 years) after adjustment for race, urban residence, and insurance status. CONCLUSIONS: Among pregnant women living in the southeastern United States, chlamydia was detected in 1 of 14 women who were tested. Chlamydia positivity was highest among women younger than 30 years. Study findings support broad screening for chlamydia in pregnancy.


Assuntos
Infecções por Chlamydia , Adulto , Infecções por Chlamydia/diagnóstico , Infecções por Chlamydia/epidemiologia , Chlamydia trachomatis , Estudos Transversais , Feminino , Humanos , Programas de Rastreamento , Gravidez , Gestantes , Prevalência , Fatores de Risco , Sudeste dos Estados Unidos
4.
Transfus Apher Sci ; 59(6): 102922, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32883593

RESUMO

SARS-CoV-2 has infected millions worldwide. The virus is novel, and currently there is no approved treatment. Convalescent plasma may offer a treatment option. We evaluated trends of IgM/IgG antibodies/plasma viral load in donors and recipients of convalescent plasma. 114/139 (82 %) donors had positive IgG antibodies. 46/114 donors tested positive a second time by NP swab. Among those retested, the median IgG declined (p < 0.01) between tests. 25/139 donors with confirmed SARS-CoV-2 were negative for IgG antibodies. This suggests that having had the infection does not necessarily convey immunity, or there is a short duration of immunity associated with a decline in antibodies. Plasma viral load obtained on 35/39 plasma recipients showed 22 (62.9 %) had non-detectable levels on average 14.5 days from positive test versus 6.2 days in those with detectable levels (p < 0.01). There was a relationship between IgG and viral load. IgG was higher in those with non-detectable viral loads. There was no relationship between viral load and blood type (p = 0.87) or death (0.80). Recipients with detectable viral load had lower IgG levels; there was no relationship between viral load, blood type or death.


Assuntos
Anticorpos Antivirais/administração & dosagem , COVID-19/sangue , COVID-19/terapia , SARS-CoV-2 , Adulto , Idoso , Feminino , Humanos , Imunização Passiva , Imunoglobulina G/administração & dosagem , Imunoglobulina M/administração & dosagem , Masculino , Pessoa de Meia-Idade , Soroterapia para COVID-19
5.
J Res Adolesc ; 30(4): 856-874, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32608182

RESUMO

This study investigates how adolescents growing up in a rapidly globalizing Thai city psychologically manage local and global values when considering their envisioned futures. Qualitative analysis of interviews conducted with 20 (16-18 years old) adolescents reveals four distinct patterns of local-global value negotiation. Findings indicate that adolescents at times dynamically reshape local values in order to encompass global values; at other times, adolescents conceive of themselves as sitting at the crossroads of value systems that cannot be readily integrated. By revealing how global youth negotiate local and global values, this study pushes forward the scientific understanding of biculturalism in contexts of rapid cultural change.


Assuntos
Comportamento do Adolescente , Negociação , Adolescente , Humanos , Tailândia
6.
Child Dev ; 90(6): 2035-2052, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-29676442

RESUMO

Around the world, adolescents increasingly grow up as members of local and global cultures. Little is known, however, about how precisely adolescents in rapidly globalizing societies blend local and global cultures. Interviews with 40 (16- to 19-year old) Thai adolescents, evenly divided between rural and urban communities, were analyzed alongside participant observation data for the interplay between local and global linguistic and dietary practices. Results revealed that urban adolescents inhabited differentiated selves, alternating between local and global practices based on interactional partner. The activation of each assisted them in navigating-and in some cases, reshaping-hierarchies encountered in everyday relationships. Findings contribute to the developmental science of globalization and point to the utility of interrogating cultural practices as sites of self-negotiation in rapidly changing cultural contexts.


Assuntos
Comportamento do Adolescente/etnologia , Cultura , Internacionalidade , Relações Interpessoais , Autoimagem , Adolescente , Adulto , Feminino , Humanos , População Rural , Tailândia/etnologia , População Urbana , Adulto Jovem
7.
New Dir Child Adolesc Dev ; 2019(164): 49-66, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30865351

RESUMO

This article explores how globalization reshapes moral development in northern Thailand. Employing a cultural-developmental approach to examine interview data gathered over the course of one year, the article discusses variations in Divinity-based moral reasoning among adolescents residing in variously globalized Thai communities. Quantitative analysis shows that moral reasoning diverges across contexts of globalization, with rural adolescents reasoning more in terms of the Ethic of Divinity than urban adolescents. Qualitative analysis shows how the meaning of Divinity diverges, with the Ethic of Divinity co-occurring alongside the Ethic of Community among rural adolescents, and the Ethic of Divinity co-occurring alongside the Ethic of Autonomy among urban adolescents. Analyses further indicate that rural and urban adolescents invoke distinct Divinity principles altogether. Findings suggest that in urban settings, Divinity is decontextualized from traditional community-driven Thai Buddhism and recontextualized to align with values that are adaptive in a globalized society. This article contributes to, and offers suggestions for, the empirical study of the moral psychology of globalization.


Assuntos
Comportamento do Adolescente/etnologia , Desenvolvimento do Adolescente , Budismo , Internacionalidade , Desenvolvimento Moral , Princípios Morais , Religião e Psicologia , Adolescente , Budismo/psicologia , Feminino , Humanos , Masculino , População Rural , Tailândia/etnologia , População Urbana
8.
PLoS Pathog ; 12(11): e1006008, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27855219

RESUMO

Subversion of host immune surveillance is a crucial step in viral pathogenesis. Epstein-Barr virus (EBV) encodes two immune evasion gene products, BCRF1 (viral IL-10) and BPLF1 (deubiquitinase/deneddylase); both proteins suppress antiviral immune responses during primary infection. The BCRF1 and BPLF1 genes are expressed during the late phase of the lytic cycle, an essential but poorly understood phase of viral gene expression. Several late gene regulators recently identified in beta and gamma herpesviruses form a viral pre-initiation complex for transcription. Whether each of these late gene regulators is necessary for transcription of all late genes is not known. Here, studying viral gene expression in the absence and presence of siRNAs to individual components of the viral pre-initiation complex, we identified two distinct groups of late genes. One group includes late genes encoding the two immunoevasins, BCRF1 and BPLF1, and is transcribed independently of the viral pre-initiation complex. The second group primarily encodes viral structural proteins and is dependent on the viral pre-initiation complex. The protein kinase BGLF4 is the only known late gene regulator necessary for expression of both groups of late genes. ChIP-seq analysis showed that the transcription activator Rta associates with the promoters of eight late genes including genes encoding the viral immunoevasins. Our results demonstrate that late genes encoding immunomodulatory proteins are transcribed by a mechanism distinct from late genes encoding viral structural proteins. Understanding the mechanisms that specifically regulate expression of the late immunomodulatory proteins could aid the development of antiviral drugs that impair immune evasion by the oncogenic EB virus.


Assuntos
Infecções por Vírus Epstein-Barr/genética , Regulação Viral da Expressão Gênica/fisiologia , Herpesvirus Humano 4/genética , Evasão da Resposta Imune/genética , Proteínas Virais/biossíntese , Proteínas Virais Reguladoras e Acessórias/biossíntese , Western Blotting , Imunoprecipitação da Cromatina , Infecções por Vírus Epstein-Barr/imunologia , Técnicas de Silenciamento de Genes , Células HEK293 , Herpesvirus Humano 4/imunologia , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Evasão da Resposta Imune/imunologia , Reação em Cadeia da Polimerase em Tempo Real , Proteínas Virais/genética , Proteínas Virais Reguladoras e Acessórias/genética , Proteínas Estruturais Virais/biossíntese
9.
PLoS Pathog ; 10(8): e1004307, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25166506

RESUMO

The mechanism regulating expression of late genes, encoding viral structural components, is an unresolved problem in the biology of DNA tumor viruses. Here we show that BGLF4, the only protein kinase encoded by Epstein-Barr virus (EBV), controls expression of late genes independent of its effect on viral DNA replication. Ectopic expression of BGLF4 in cells lacking the kinase gene stimulated the transcript levels of six late genes by 8- to 10-fold. Introduction of a BGLF4 mutant that eliminated its kinase activity did not stimulate late gene expression. In cells infected with wild-type EBV, siRNA to BGLF4 (siG4) markedly reduced late gene expression without compromising viral DNA replication. Synthesis of late products was restored upon expression of a form of BGLF4 resistant to the siRNA. Studying the EBV transcriptome using mRNA-seq during the late phase of the lytic cycle in the absence and presence of siG4 showed that BGLF4 controlled expression of 31 late genes. Analysis of the EBV transcriptome identified BGLF3 as a gene whose expression was reduced as a result of silencing BGLF4. Knockdown of BGLF3 markedly reduced late gene expression but had no effect on viral DNA replication or expression of BGLF4. Our findings reveal the presence of a late control locus encompassing BGLF3 and BGLF4 in the EBV genome, and provide evidence for the importance of both proteins in post-replication events that are necessary for expression of late genes.


Assuntos
Regulação Viral da Expressão Gênica/genética , Proteínas Serina-Treonina Quinases/biossíntese , Proteínas Serina-Treonina Quinases/genética , Proteínas Virais/biossíntese , Proteínas Virais/genética , Proteínas Estruturais Virais/biossíntese , Proteínas Estruturais Virais/genética , Northern Blotting , Loci Gênicos , Células HEK293 , Humanos , Reação em Cadeia da Polimerase em Tempo Real , Transfecção , Replicação Viral/genética
10.
Curr Top Microbiol Immunol ; 391: 237-61, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26428377

RESUMO

Epstein-Barr virus, which mainly infects B cells and epithelial cells, has two modes of infection: latent and lytic. Epstein-Barr virus infection is predominantly latent; however, lytic infection is detected in healthy seropositive individuals and becomes more prominent in certain pathological conditions. Lytic infection is divided into several stages: early gene expression, DNA replication, late gene expression, assembly, and egress. This chapter summarizes the most recent progress made toward understanding the molecular mechanisms that regulate the different lytic stages leading to production of viral progeny. In addition, the chapter highlights the potential role of lytic infection in disease development and current attempts to purposely induce lytic infection as a therapeutic approach.


Assuntos
Infecções por Vírus Epstein-Barr/virologia , Herpesvirus Humano 4/fisiologia , Ativação Viral , Animais , Linfócitos B/virologia , Regulação Viral da Expressão Gênica , Herpesvirus Humano 4/genética , Humanos , Latência Viral
11.
Child Dev ; 87(2): 446-64, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26659260

RESUMO

This cultural-developmental interview study examined moral reasoning in relation to religious culture (evangelical, mainline Protestants), age (children, adolescents, adults), and moral issue (public, private; N = 120). Compared to adolescents and adults, children used more Ethic of Autonomy and less Ethic of Community reasoning. With age, differences between religious cultures became pronounced. Mainline adults invoked an Ethic of Divinity for private issues. Evangelical adolescents and adults used this ethic frequently, but more for public than private issues. These and other findings indicate that evangelical and mainline Protestants diverge on what should be society's moral lingua franca, and cast new and nuanced light on America's "culture wars." Results furthermore highlight comodulation of development and culture that requires life course research on moral reasoning.


Assuntos
Desenvolvimento Humano , Princípios Morais , Protestantismo/psicologia , Religião e Psicologia , Pensamento , Adolescente , Adulto , Fatores Etários , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estados Unidos/etnologia
13.
bioRxiv ; 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38826465

RESUMO

The physical characteristics of brown adipose tissue (BAT) are defined by the presence of multilocular lipid droplets (LD) within the brown adipocytes and a high abundance of iron-containing mitochondria, which give it its characteristic color. Normal mitochondrial function is, in part, regulated by organelle-to-organelle contacts. Particularly, the contact sites that mediate mitochondria-LD interactions are thought to have various physiological roles, such as the synthesis and metabolism of lipids. Aging is associated with mitochondrial dysfunction, and previous studies show that there are changes in mitochondrial structure and proteins that modulate organelle contact sites. However, how mitochondria-LD interactions change with aging has yet to be fully clarified. Therefore, we sought to define age-related changes in LD morphology and mitochondria-lipid interactions in BAT. We examined the three-dimensional morphology of mitochondria and LDs in young (3-month) and aged (2-year) murine BAT using serial block face-scanning electron microscopy and the Amira program for segmentation, analysis, and quantification. Analysis showed reductions in LD volume, area, and perimeter in aged samples compared to young samples. Additionally, we observed changes in LD appearance and type in aged samples compared to young samples. Notably, we found differences in mitochondrial interactions with LDs, which could implicate that these contacts may be important for energetics in aging. Upon further investigation, we also found changes in mitochondrial and cristae structure for mitochondria interacting with LD lipids. Overall, these data define the nature of LD morphology and organelle-organelle contacts during aging and provide insight into LD contact site changes that interconnect biogerontology and mitochondrial functionality, metabolism, and bioactivity in aged BAT.

14.
bioRxiv ; 2023 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-37292887

RESUMO

The Sorting and Assembly Machinery (SAM) Complex is responsible for assembling ß-barrel proteins in the mitochondrial membrane. Comprising three subunits, Sam35, Sam37, and Sam50, the SAM complex connects the inner and outer mitochondrial membranes by interacting with the mitochondrial contact site and cristae organizing system (MICOS) complex. Sam50, in particular, stabilizes the mitochondrial intermembrane space bridging (MIB) complex, which is crucial for protein transport, respiratory chain complex assembly, and regulation of cristae integrity. While the role of Sam50 in mitochondrial structure and metabolism in skeletal muscle remains unclear, this study aims to investigate its impact. Serial block-face-scanning electron microscopy (SBF-SEM) and computer-assisted 3D renderings were employed to compare mitochondrial structure and networking in Sam50-deficient myotubes from mice and humans with wild-type (WT) myotubes. Furthermore, autophagosome 3D structure was assessed in human myotubes. Mitochondrial metabolic phenotypes were assessed using Gas Chromatography-Mass Spectrometry-based metabolomics to explore differential changes in WT and Sam50-deficient myotubes. The results revealed increased mitochondrial fragmentation and autophagosome formation in Sam50-deficient myotubes compared to controls. Metabolomic analysis indicated elevated metabolism of propanoate and several amino acids, including ß-Alanine, phenylalanine, and tyrosine, along with increased amino acid and fatty acid metabolism in Sam50-deficient myotubes. Furthermore, impairment of oxidative capacity was observed upon Sam50 ablation in both murine and human myotubes, as measured with the XF24 Seahorse Analyzer. Collectively, these findings support the critical role of Sam50 in establishing and maintaining mitochondrial integrity, cristae structure, and mitochondrial metabolism. By elucidating the impact of Sam50-deficiency, this study enhances our understanding of mitochondrial function in skeletal muscle.

15.
J Matern Fetal Neonatal Med ; 35(25): 8975-8981, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34823422

RESUMO

OBJECTIVE: To determine the obstetrical outcomes of women delivered for the diagnosis of intrahepatic cholestasis of pregnancy (ICP). METHODS: Retrospective study of singleton pregnancies diagnosed with ICP between 1 May 2014 and 31 December 2017. Population was analyzed based on bile acids: normal (<10 µmol/L), mild (10 to 40 µmol/L), moderate-severe (>40 µmol/L), and not obtained. Receiver operating characteristic curves established critical values for aspartate aminotransferase (AST) and alanine aminotransferase (ALT) to predict elevated bile acids. Statistical analyses included χ2 for categorical variables and ANOVA for continuous variables. All tests used a 2-sided α level of significance of .05. RESULTS: Bile acids were normal in 39 (45.9%) women, 30 (35.3%) had mild cholestasis, 10 (11.8%) had moderate-severe cholestasis and not obtained for six (7%) women. Gestational diabetes was more common in mild cholestasis (p = .03). There were no differences in demographics, clinical presentation, obstetric interventions and neonatal outcomes. Bile acids took 5-6 days to result. Rate of labor inductions was high in all groups. Postpartum complications occurred in four women in the normal group and in one woman in the mild cholestasis group. Five (12.8%) neonates in the normal group, six (20%) in the mild group, and one (10%) in the severe group were admitted to the NICU. There was no fetal asphyxia, no 5-minute Apgar score <7, and no perinatal deaths. An AST of 27.5 IU/L (p = .002) with sensitivity of 81% and specificity of 76%, and an ALT of 26.7 IU/L (p = .004) with sensitivity of 78% and specificity of 68% predicted elevated bile acids. Improving the sensitivity of AST and ALT to 95%, the ROC curve identified an AST of 62 IU/L with a specificity, positive and negative predictive values of 32, 58 and 86%, respectively; and an ALT of 106 IU/L with a specificity, positive and negative predictive values of 27, 57 and 83%, respectively. CONCLUSIONS: ICP should not be presumed in patients with pruritus. This practice may lead to early term delivery and associated complications.


Assuntos
Colestase Intra-Hepática , Complicações na Gravidez , Gravidez , Recém-Nascido , Humanos , Feminino , Masculino , Resultado da Gravidez/epidemiologia , Estudos Retrospectivos , Colestase Intra-Hepática/diagnóstico , Colestase Intra-Hepática/epidemiologia , Colestase Intra-Hepática/complicações , Complicações na Gravidez/diagnóstico , Complicações na Gravidez/epidemiologia , Ácidos e Sais Biliares
16.
Hum Gene Ther ; 33(23-24): 1279-1292, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36226412

RESUMO

Mucopolysaccharidosis type II (MPS II, Hunter syndrome) is an X-linked recessive lysosomal disease caused by deficiency of iduronate-2-sulfatase (IDS). The absence of IDS results in the accumulation of the glycosaminoglycans (GAGs) heparan sulfate and dermatan sulfate. Currently, the only approved treatment option for MPS II is enzyme replacement therapy (ERT), Elaprase. However, ERT is demanding for the patient and does not ameliorate neurological manifestations of the disease. Using an IDS-deficient mouse model that phenocopies the human disease, we evaluated hematopoietic stem and progenitor cells (HSPCs) transduced with a lentiviral vector (LVV) carrying a codon-optimized human IDS coding sequence regulated by a ubiquitous MNDU3 promoter (MNDU3-IDS). Mice treated with MNDU3-IDS LVV-transduced cells showed supraphysiological levels of IDS enzyme activity in plasma, peripheral blood mononuclear cells, and in most analyzed tissues. These enzyme levels were sufficient to normalize GAG storage in analyzed tissues. Importantly, IDS levels in the brains of MNDU3-IDS-engrafted animals were restored to 10-20% than that of wild-type mice, sufficient to normalize GAG content and prevent emergence of cognitive deficit as evaluated by neurobehavioral testing. These results demonstrate the potential effectiveness of ex vivo MNDU3-IDS LVV-transduced HSPCs for treatment of MPS II.


Assuntos
Iduronato Sulfatase , Mucopolissacaridose II , Animais , Camundongos , Humanos , Mucopolissacaridose II/genética , Mucopolissacaridose II/terapia , Leucócitos Mononucleares , Iduronato Sulfatase/genética , Terapia de Reposição de Enzimas , Modelos Animais de Doenças , Células-Tronco Hematopoéticas
17.
J Biol Chem ; 285(44): 34191-201, 2010 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-20685647

RESUMO

The human mitochondrial DNA polymerase (pol γ) is nuclearly encoded and is solely responsible for the replication and repair of the mitochondrial genome. The progressive accumulation of mutations within the mitochondrial genome is thought to be related to aging, and mutations in the pol γ gene are responsible for numerous heritable disorders including progressive external opthalmoplegia, Alpers syndrome, and parkinsonism. Here we investigate the kinetic effect of H932Y, a mutation associated with opthalmoplegia. Mutations H932Y and H932A reduce the specificity constant governing correct nucleotide incorporation 150- and 70-fold, respectively, without significantly affecting fidelity of incorporation or the maximum rate of incorporation. However, this leads to only a 2-fold reduction in rate of incorporation at a physiological nucleotide concentration (∼100 µm). Surprisingly, incorporation of T:T or C:T mismatches catalyzed by either H932Y or H932A mutants was followed by slow pyrophosphate release (or fast pyrophosphate rebinding). Also, H932Y readily catalyzed incorporation of multiple mismatches, which may have a profound physiological impact over time. His-932 is thought to contact the ß-phosphate of the incoming nucleotide, so it is perhaps surprising that H932Y appears to slow rather than accelerate pyrophosphate release.


Assuntos
DNA Polimerase Dirigida por DNA/química , Histidina/química , Mitocôndrias/enzimologia , Nucleotídeos/química , Pareamento Incorreto de Bases , Catálise , Clonagem Molecular , DNA/química , Difosfatos/química , Genoma Mitocondrial , Humanos , Cinética , Mutagênese , Mutação , Doença de Parkinson/enzimologia
18.
Animals (Basel) ; 11(1)2021 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-33430130

RESUMO

Current evidence of how human sex-related differences in riders and handlers may influence horse behaviour is limited. The Equine Behaviour Assessment and Research Questionnaire (E-BARQ) was used to collect demographic data on riders and handlers (n = 1420) and behavioural data on their horses. It includes demographic items about the sex of the respondent and how frequently the horse has been ridden or handled by male and female humans. The questionnaire then gathers observations on the horse's behaviour on the ground and under saddle or when driven. Using E-BARQ's battery of 97 questions, the current study showed differences in ridden and non-ridden horse behaviour that were related to the sex of the rider or handler. Data were evaluated using multivariate analysis and revealed that horses handled by male humans were significantly more difficult to catch (t-value = -3.11; p = 0.002) and significantly more defensive when approached (t-value = -2.104; p = 0.035), but significantly less likely to pull on the reins/brace the neck or toss their head (t-value 1.980; p = 0.048) than horses handled more frequently by female humans. The differences found between male and female horse handlers suggest that sex is an important factor to consider when understanding equine behaviour. Our study explored reported differences in confidence, handling and working compliance and touch sensitivity among horses ridden and handled by male and female humans and suggested further research into how these differences are gendered.

19.
Ecol Evol ; 11(23): 16874-16889, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34938479

RESUMO

Between 2013 and 2019, 63 presumed Chinook salmon Oncorhynchus tshawytscha sampled primarily in the Strait of Georgia (0.63% of total sample) were identified as potential Chinook-Coho (Oncorhynchus kisutch) hybrids by the presence of anomalous microsatellite genotypes. Their hybrid origin was confirmed by single nucleotide polymorphism amplification of two species-specific amplicons. Mitochondrial DNA indicated that most of these fish resulted from the hybridization of Coho salmon females and Chinook salmon males. Although no diagnostic external features were identified, several individuals displayed an abnormal scale arrangement on the caudal peduncle. One hybrid juvenile examined for meristics exhibited a pyloric caeca count intermediate between published values for Chinook and Coho salmon. Most hybrids originated in the Cowichan River during the 2014 brood year. Their prevalence in the watershed is a naturally occurring event, likely exacerbated by prolonged low water levels which limit habitat and delay Chinook salmon spawning, in addition to the differential abundance of the parental species. This research is the first to document ongoing natural hybridization (Chinook-Coho salmon crosses) and link it to habitat and climatic changes, and includes the identification of eight F1 adults and two juvenile backcross or F2 hybrids. The potential negative impacts of hybridization, particularly in Coho salmon through potential introgression, warrant hybrid identification as an ecosystem monitoring tool within a survey program.

20.
Australas J Ageing ; 39(1): 21-30, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31250961

RESUMO

OBJECTIVE: To determine if family caregiver involvement in interventions with patients with delirium improves patient outcomes. METHODS: A search of three databases (Medline-Ovid, CINAHL and Embase) was conducted. Eligibility criteria included adult patients and involvement of family caregivers in any delirium intervention. Data were extracted from each study (determined by PEDro scale) using a customised form. A meta-analysis was undertaken which compared the length of hospital stay and duration of delirium. PROSPERO registration number is CRD42017077650. RESULTS: Five studies involving 505 participants published over a 5-year period were suitable for inclusion. Low-level evidence demonstrated family caregiver involvement may reduce caregiver's anxiety and hospital staff viewed administration of education to family caregivers as efficient. Meta-analysis suggested family interventions reduce length of hospital stay for patients with delirium. It remains unclear if it affects the duration of delirium. CONCLUSION: Family caregivers providing interventions to patients with delirium can improve patient outcomes.


Assuntos
Cuidadores , Delírio/terapia , Família , Humanos , Tempo de Internação
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