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1.
Domest Anim Endocrinol ; 84-85: 106806, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37392553

RESUMO

Recent research has suggested that different cattle breed types may respond differently to anabolic implant protocols of varying intensity. Therefore, the purpose of this research was to compare anabolic implant protocols in feedlot steers of 2 different breed types. Sixty steers were stratified by weight and breed in a 2 × 3 factorial design examining 2 different breeds: Angus (AN; n=38) or Santa Gertrudis influenced (SG; n=22), and 3 implant strategies: no implant (CON; n=20), a moderate intensity implant protocol (d0 implant: Revalor-G, d56 implant: Revalor-IS, d112 implant: Revalor-S; MI; n=20), or a high intensity implant protocol (d0 implant: Revalor-IS, d56 implant: Revalor-S, d112 implant: Revalor-200; HI; n=20). Steers were randomly placed into pens equipped with GrowSafe bunks to collect dry matter intake and feeding behavior. All animals were fed the same diet. Weight, chute score, exit velocity, serum, rectal temperature, hip height and 12th rib fat thickness were collected approximately every 28 d over a 196 d period. Serum urea nitrogen (SUN) was evaluated as well. Total average daily gain was increased (P < 0.0001) in both the HI and MI steers compared to the CON steers by 29.4% and 26%, respectively. A treatment × breed interaction was observed (P < 0.0001) for hip height, with AN-CON steers being shorter (P < 0.0007) than AN-HI, SG-CON, SG-MI, and SG-HI steers. A breed × treatment interaction was observed (P < 0.004) for chute score and rectal temperature, with SG-HI and SG-MI steers having increased chute scores (P < 0.001) when compared to AN-HI, AN-MI, AN-CON, and SG-CON throughout the course of the trial. Additionally, SG-HI and SG-MI steers had an increased rectal temperature (P < 0.004) compared to AN-HI, AN-MI, AN-CON, and SG-CON steers. A breed effect was observed (P = 0.002) for SUN with AN steers having increased (P = 0.002) SUN concentration compared to SG sired steers, in addition to a treatment effect (P < 0.0001), with CON steers having a higher (P < 0.0001) SUN concentration than MI and HI steers, regardless of breed. The MI implant protocol increased net return per head, on average, by $97.28, regardless of breed, while the HI implant protocol increased net return by only $80.84. Taken together, despite the cattle breed types responding differently to the different anabolic implant protocols at times, a moderate intensity anabolic implant protocol was optimal in this experiment for steers raised in a temperate climate.


Assuntos
Dieta , Temperamento , Animais , Bovinos/genética , Ração Animal/análise , Nitrogênio da Ureia Sanguínea , Composição Corporal , Dieta/veterinária , Comportamento Alimentar
2.
medRxiv ; 2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36778369

RESUMO

Background: South Africa has homicide rates six times the global average, predominantly among men, but little is known about male victims. As part of the country's first ever study of male homicide we compared 2017 male and female victim profiles for selected covariates, against global averages and previous estimates for 2009. Methods: We conducted a retrospective descriptive study of routine data collected through postmortem investigations, calculating age-standardised mortality rates for manner of death by age, sex and province and male-to-female incidence rate ratios with 95% confidence intervals. We then used generalised linear models and linear regression models to assess the association between sex and victim characteristics including age and mechanism of injury (guns, stabs and blunt force) within and between years. Findings: 87% of 19,477 homicides in 2017 were males, equating to seven male deaths for every female, with sharp force and firearm discharge the most common external causes. Rates were higher among males than females at all ages, and up to eight times higher among males aged 15-44 years. Provincial rates varied overall and by sex, with the highest comparative risk for men vs. women in the Western Cape Province (11.4 males for every 1 female). Male homicides peaked during December and were highest on weekends, underscoring the prominent role of alcohol as a risk factor. Significantly more males tested positive for alcohol than females. Interpretation: The massive, disproportionate and enduring homicide risk borne by adult South African men highlights the negligible prevention response. Only through challenging the normative perception of male invulnerability can we begin to address the enormous burden of violence impacting men. There is an urgent need to address the insidious effect of such societal norms alongside implementing structural interventions to overcome the root causes of poverty and inequality and better control alcohol and firearms. Funding: South African Medical Research Council and Ford Foundation.

3.
S Afr Med J ; 112(7): 451-452, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-36217853

RESUMO

Letter by Matzopoulos et al. on article by Murray and Barr (Murray M, Barr GDI. The cost of harmful alcohol use in South Africa: A commentary. S Afr Med J 2022;112(3):187-188. https://doi.org/10.7196/SAMJ.2022.v112i3.16354).


Assuntos
Alcoolismo , Alcoolismo/epidemiologia , Humanos , África do Sul/epidemiologia
4.
Theriogenology ; 192: 52-61, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-36049382

RESUMO

Nocardioform placentitis (NP) has been associated with mid to late pregnancy loss in mares. To date, disease outbreaks have been described only in central Kentucky, although sporadic, isolated cases have been reported globally. This study describes a series of cases of NP that occurred in a sample population of 299 mares foaling in southeastern Pennsylvania and northeastern Maryland in 2020. These cases coincided with an outbreak of NP that occurred in Kentucky that same year. On farms that reported information on both normal and abnormal foalings, nocardioform organisms/DNA were isolated from 6.3% of placental samples based on aerobic culture and/or PCR. In cases with characteristic gross lesions of the chorion, 41% of cases were positive on aerobic culture and/or PCR. NP was confirmed in 16 mares that had not resided in Kentucky for breeding or any part of gestation. Characteristics of mares confirmed positive for NP, including age, gestation length, and problems during gestation are described. Standardbred mares bred by artificial insemination were less likely to be affected than Thoroughbred mares bred by natural cover. Affected mares had prolonged Stage III labor compared with normal mares. These findings suggest that regional increases in NP may occur outside of Kentucky, potentially in parallel with Kentucky outbreaks.


Assuntos
Doenças dos Cavalos , Doenças Placentárias , Aborto Animal/epidemiologia , Animais , Feminino , Doenças dos Cavalos/epidemiologia , Doenças dos Cavalos/patologia , Cavalos , Maryland/epidemiologia , Pennsylvania/epidemiologia , Placenta/patologia , Doenças Placentárias/veterinária , Gravidez
5.
J Musculoskelet Neuronal Interact ; 11(3): 234-42, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21885898

RESUMO

OBJECTIVES: Neonatal stress impairs postnatal bone mineralization. Evidence suggests that mechanical tactile stimulation (MTS) in early life decreases stress hormones and improves bone mineralization. Insulin-like growth factor (IGF1) is impacted by stress and essential to bone development. We hypothesized that MTS administered during neonatal stress would improve bone phenotype in later life. We also predicted an increase in bone specific mRNA expression of IGF1 related pathways. METHODS: Neonatal stress (STRESS) and MTS (STRESS+10 min of MTS) were given from D6 to D10 of rat life and tissue was harvested on D60 of life. Dual energy x-ray absorptiometry (DXA), bone morphometry, serum osteocalcin, type I procollagen N-terminal propeptide (PINP), tartrate-resistant acid phosphatase (TRAP), and bone and liver mRNA levels of IGF1, IGF1 receptor (IGF1R), and growth hormone receptor (GHR) were measured. RESULTS: Stress resulted in reduced bone area and bone mineral content (BMC) compared to naive control (CTL). MTS intervention increased BMC and tibial growth plate width compared to STRESS. MTS also resulted in higher osteocalcin, and, in males, lower TRAP (p<0.05). MTS resulted in three-fold, two-fold, and six-fold higher bone specific IGF1, IGF1R, and GHR, respectively (p ≤ 0.001) compared to STRESS. CONCLUSIONS: MTS in early postnatal life improves long-term bone mineralization. IGF1 and related pathways may explain improved BMC.


Assuntos
Desenvolvimento Ósseo/fisiologia , Reabsorção Óssea/fisiopatologia , Reabsorção Óssea/terapia , Estresse Psicológico/fisiopatologia , Estresse Psicológico/terapia , Tato/fisiologia , Animais , Animais Recém-Nascidos , Reabsorção Óssea/etiologia , Modelos Animais de Doenças , Feminino , Masculino , Estimulação Física/métodos , Gravidez , Ratos , Ratos Sprague-Dawley , Estresse Psicológico/complicações
6.
Plant Dis ; 94(11): 1361-1365, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30743626

RESUMO

Black shank is an important disease of tobacco (Nicotiana tabacum) caused by the fungus-like organism, Phytophthora nicotianae. Three physiological races (0, 1, and 3) have been documented in the United States. Shifts in the pathogen population structure have become a concern due to the widespread use of cultivars possessing resistance to race 0 arising from a single gene (Php or Phl). A comprehensive statewide survey conducted throughout major tobacco-growing areas during summer 2006 and supplemented by additional isolates in 2007 and 2008 yielded 217 isolates from flue-cured, burley, and dark fire-cured tobacco fields. After determining species identity using a single-strand conformational polymorphism fingerprinting technique, the race identity of isolates was assessed via greenhouse tests using three differential cultivars (Hicks, L8, and NC1071). Approximately 76% of the isolates belonged to race 1, 21% to race 0, and the remaining 3% were race 3. This race structure was comparable with those in the other tobacco-producing states in the United States. Approximately 94% of isolates belonged to A2 mating type and merely 6% were A1. These data suggest that it is unlikely that sexual recombination serves as a major mechanism enhancing the genetic diversity of the pathogen in Virginia. All isolates were also evaluated against mefenoxam at 5 µg/ml. None were insensitive; 98% of isolates were either highly sensitive or sensitive and the remaining 2% were intermediately sensitive. These results indicate that mefenoxam remains effective for control of black shank in Virginia. The results of this study can assist breeders to develop cultivars possessing the most appropriate set of disease resistance traits, as well as extension specialists, county agents, and tobacco growers in their decision-making process to manage tobacco black shank in Virginia.

7.
Science ; 164(3877): 325-6, 1969 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-5776644

RESUMO

Ciliary inhibition in oysters serves as an assay in identifying a serum factor in cystic fibrosis patients and heterozygotes. Seriums from 47 patients With cystic fibrosis antd 19 heterozygotes caused ciliary cessation within 35 minutes, whereas serums from only 2 of 64 individuals without cystic fibrosis inhibited ciliary activity within this time.


Assuntos
Cílios/efeitos dos fármacos , Fibrose Cística/sangue , Brânquias/fisiologia , Moluscos , Animais , Asma/sangue , Depressão Química , Heterozigoto , Humanos , Rinite Alérgica Sazonal/sangue , Água do Mar
8.
Science ; 167(3919): 871-3, 1970 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-5410849

RESUMO

The inhibitor to oyster ciliary activity was isolated from serumof cystic fibrosis patients and heterozygotes. The inhibitinig protein fraction wast a cation as judged by electrophoresis; it had a molecuer weight of 125,000 to 200,000 as judged by gel filtration; antd oil diethylaminoethyl-cellulose chromatography it eluted with the immunoglobulin G fraction. The analogous fraction in normal individuals did not inhibit oyster cillary activity.


Assuntos
Cílios/efeitos dos fármacos , Fibrose Cística/sangue , Brânquias/efeitos dos fármacos , Extratos de Tecidos/farmacologia , Animais , Eletroforese das Proteínas Sanguíneas , Cromatografia em Gel , Heterozigoto , Humanos , Imunoglobulina G , Peso Molecular , Moluscos
9.
S Afr Med J ; 109(6): 382-386, 2019 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-31266555

RESUMO

The Sustainable Development Goals (SDGs) have highlighted interpersonal violence and violence against women and girls as impediments to development globally. South Africa is adversely affected by violence and injury. The annual Victims of Crime Survey (VoCS) provides a potentially useful source of complementary data to bolster vital registration and police crime statistics, but it may not provide data that are sufficiently accurate and reliable to inform prevention efforts. We conducted a critical assessment of the VoCS's methodological robustness and strength as a data source for high-level analyses, adopting a public health and SDGs monitoring perspective that was based on expert opinion and comparison with other data sources. We concluded that either the survey methods should be improved to provide findings that are better aligned with the SDGs agenda and are robust enough to inform high-quality research and prevention, or the funds used to conduct the VoCS should be redirected to other more suitable instruments.


Assuntos
Saúde Pública , Desenvolvimento Sustentável , Violência/prevenção & controle , Crime/prevenção & controle , Crime/estatística & dados numéricos , Vítimas de Crime , Violência de Gênero/prevenção & controle , Violência de Gênero/estatística & dados numéricos , Homicídio/prevenção & controle , Homicídio/estatística & dados numéricos , Humanos , Armazenamento e Recuperação da Informação , Delitos Sexuais/prevenção & controle , Delitos Sexuais/estatística & dados numéricos , África do Sul , Inquéritos e Questionários , Violência/estatística & dados numéricos
10.
Curr Opin Genet Dev ; 1(4): 451-6, 1991 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1822276

RESUMO

The avalanche of molecular sequence data from a wide variety of organisms and genes makes the construction and testing of evolutionary trees a widespread and demanding activity. We present the most recent advances in the interpretation of molecular data, as well as recent phylogenetic results affecting both molecular evolutionary biology and other areas of biological research.


Assuntos
Biologia Molecular/métodos , Filogenia , Grupos de População Animal/classificação , Grupos de População Animal/genética , Animais , Animais Domésticos/classificação , Animais Domésticos/genética , Bactérias/classificação , Bactérias/genética , DNA/genética , DNA Mitocondrial/genética , Etnicidade/genética , Cobaias/classificação , Cobaias/genética , Humanos , Mutação
11.
J Clin Invest ; 52(11): 2732-6, 1973 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-4201263

RESUMO

An inhibitor of ciliary activity is present in the serum of cystic fibrosis (CF) patients and heterozygotes. Fractionation of CF serum has indicated that the inhibitor is associated with the serum IgG fraction. This study compared the activity of the CF inhibitor to that of rabbit antibody preparations directed against oyster cilia. The aim of this investigation was to determine whether the ciliary inhibitory mechanism in cystic fibrosis is related to a typical immunological reaction. Results from experiments utilizing fluorescent antibody techniques demonstrated that an antiserum directed against oyster ciliated epithelium binds immunologically with both human bronchial and oyster epithelial tissue. Results from experiments utilizing immunofluorescent tracing, passive hemagglutination, double immunodiffusion, and papain digestion, however, indicated that the interaction between the oyster cilia and the CF serum inhibitor was not a typical antigen-antibody reaction.


Assuntos
Anticorpos , Cílios/imunologia , Fibrose Cística/imunologia , Animais , Formação de Anticorpos , Brônquios/imunologia , Cromatografia DEAE-Celulose , Eritrócitos/imunologia , Imunofluorescência , Brânquias/imunologia , Hemaglutinação , Humanos , Soros Imunes , Imunodifusão , Fragmentos Fab das Imunoglobulinas/isolamento & purificação , Fragmentos Fc das Imunoglobulinas/isolamento & purificação , Imunoglobulina G/isolamento & purificação , Ostreidae , Papaína/farmacologia , Coelhos/imunologia , Ovinos/imunologia
12.
J Clin Invest ; 77(3): 841-9, 1986 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3005367

RESUMO

Transferrin (Tf) is a growth factor that transports iron in plasma. It is essential for proliferation of activated T lymphocytes. Previous studies have suggested that peripheral blood cells are capable of synthesizing Tf. Using in situ hybridization techniques and human Tf complementary DNAs as probes, peripheral blood cells have been examined for sites of Tf messenger RNA (mRNA) transcription. The studies described here demonstrate that Tf is synthesized by a specific subset of T lymphocytes, the T4+ inducer subset. T lymphocyte proliferation is dependent upon the presence of both interleukin 2 (IL-2) and Tf, even though resting cells do not possess receptors for either. The present studies indicate that during T cell activation, induction of IL-2 mRNA transcription and IL-2 receptor expression precede the transcription of Tf mRNA and expression of Tf receptors, respectively. These events in turn precede the initiation of DNA synthesis. Transferrin and its receptor appear to be involved in an autocrine pathway which is functionally linked to the IL-2/IL-2 receptor autocrine loop.


Assuntos
Linfócitos T/metabolismo , Transferrina/biossíntese , Ciclo Celular , Meios de Cultura , Regulação da Expressão Gênica , Humanos , Técnicas In Vitro , Interleucina-2/fisiologia , Ativação Linfocitária , RNA Mensageiro/genética , Receptores de Superfície Celular/metabolismo , Receptores Imunológicos/fisiologia , Receptores de Interleucina-2 , Receptores da Transferrina , Linfócitos T Auxiliares-Indutores/metabolismo , Fatores de Tempo , Transferrina/genética
13.
Br J Sports Med ; 41(10): 639-43; discussion 643, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17502333

RESUMO

There is increasing concern in Australia about safety in the thoroughbred racing industry, but there has been no reported analysis of injury data. This review analyses injury and workers' compensation data recorded in Victoria. On the basis of the results, it is recommended that the injury and incident data collection systems are improved such that they are not only more complete but also accumulate more detailed information about the location of an incident or injury event, the activity at the time of the incident or injury event, and factors that may have influenced the occurrence.


Assuntos
Traumatismos em Atletas/epidemiologia , Cavalos , Doenças Profissionais/epidemiologia , Esportes , Acidentes de Trabalho/estatística & dados numéricos , Animais , Humanos , Incidência , Fatores de Risco , Vitória/epidemiologia , Indenização aos Trabalhadores
14.
Mucosal Immunol ; 9(6): 1584-1595, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-26883728

RESUMO

Although the development of a fully protective HIV vaccine is the ultimate goal of HIV research, to date only one HIV vaccine trial, the RV144, has successfully induced a weakly protective response. The 31% protection from infection achieved in the RV144 trial was linked to the induction of nonneutralizing antibodies, able to mediate antibody-dependent cell-mediated cytotoxicity (ADCC), suggestive of an important role of Fc-mediated functions in protection. Similarly, Fc-mediated antiviral activity was recently shown to play a critical role in actively suppressing the viral reservoir, but the Fc effector mechanisms within tissues that provide protection from or after infection are largely unknown. Here we aimed to define the landscape of effector cells and Fc receptors present within vulnerable tissues. We found negligible Fc receptor-expressing natural killer cells in the female reproductive and gastrointestinal mucosa. Conversely, Fc receptor-expressing macrophages were highly enriched in most tissues, but neutrophils mediated superior antibody-mediated phagocytosis. Modifications in Fc domain of VRC01 antibody increased phagocytic responses in both phagocytes. These data suggest that non-ADCC-mediated mechanisms, such as phagocytosis and neutrophil activation, are more likely to play a role in preventative vaccine or reservoir-eliminating therapeutic approaches.


Assuntos
Vacinas contra a AIDS/imunologia , Infecções por HIV/imunologia , Infecções por HIV/metabolismo , HIV-1/imunologia , Fagocitose/imunologia , Receptores Fc/metabolismo , Adulto , Anticorpos Monoclonais/imunologia , Biomarcadores , Anticorpos Amplamente Neutralizantes , Citocinas/metabolismo , Feminino , Expressão Gênica , Anticorpos Anti-HIV/imunologia , Infecções por HIV/prevenção & controle , Infecções por HIV/virologia , Humanos , Imunidade Inata , Mediadores da Inflamação/metabolismo , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Macrófagos/imunologia , Macrófagos/metabolismo , Pessoa de Meia-Idade , Mucosa/imunologia , Mucosa/metabolismo , Mucosa/virologia , Neutrófilos/imunologia , Neutrófilos/metabolismo , Receptores Fc/genética , Adulto Jovem
15.
Biochim Biophys Acta ; 667(1): 23-34, 1981 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-6163473

RESUMO

Low molecular weight proteins co-purified with IgG constitute 0.22% of the total protein purified from human plasma by ion-exchange chromatography on DEAE-cellulose. We have found that these low molecular weight proteins were obtained free of immunoglobulin by ultrafiltration in 5 M guanidinium chloride. Electrophoresis and isoelectric focusing in polyacrylamide gels demonstrated that this fraction of low molecular weight proteins is remarkably heterogeneous. Chromatography of an Mr 6000 to 12 000 fraction on hydroxyapatite resolved fourteen discrete protein peaks. Three of the peaks contained proteins which appeared to be homogeneous on acid-urea polyacrylamide gels. Two of these proteins were similar in composition to B2 globulin and may represent degradation products of some larger protein. The third protein was found to have an amino-terminal sequence identical to C3a. This population of low molecular weight plasma proteins has previously been shown to contain the cystic fibrosis mucociliary inhibitor and is here shown to contain two proteins similar to B2 globulin, C3a and many proteins remaining to be characterized. The presence of these low molecular weight proteins in measurable concentrations may be insufficiently appreciated in studies using 'purified' immunoglobulins as biological or chemical probes.


Assuntos
Proteínas Sanguíneas/isolamento & purificação , Imunoglobulina G/isolamento & purificação , Sequência de Aminoácidos , Anafilatoxinas/isolamento & purificação , beta-Globulinas , Cromatografia , Complemento C3/isolamento & purificação , Complemento C3a , Eletroforese em Gel de Poliacrilamida , Humanos , Imunoglobulina G/normas , Focalização Isoelétrica , Peso Molecular , Ultrafiltração
16.
Biochim Biophys Acta ; 1273(2): 77-83, 1996 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-8611592

RESUMO

The vma-6 gene, encoding a membrane-associated subunit of the vacuolar H+-ATPase from Neurospora crassa, was cloned and sequenced. The gene contains three small introns and encodes a protein of 41 005 Da. When compared with homologous polypeptides from other species, the N. crassa protein contains a unique glycine-rich region. Three conserved cysteine residues, previously unrecognized, have been identified. An unrelated gene encoding a protein of 31 701 Da was found 2.1 kb downstream of vma-6. The second appears to encode the N. crassa homolog of a ribosome-associated protein identified previously in several plant and mammalian cells, and was named rap-1.


Assuntos
Adenosina Trifosfatases/genética , Neurospora crassa/genética , Proteínas Ribossômicas/genética , Sequência de Aminoácidos , Sequência de Bases , Clonagem Molecular , Dados de Sequência Molecular , Neurospora crassa/metabolismo , Alinhamento de Sequência , Vacúolos/enzimologia
17.
Biochim Biophys Acta ; 434(2): 452-61, 1976 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-952897

RESUMO

Ceruloplasmin from nephrotic urine, ascites fluid and plasma has been partially characterized. All ceruloplasmin preparations were found to be comprised of two light and two heavy polypeptide subunits. Characterization of the purified subunits indicated that the alpha chain had a mol. wt. of 16000 and had N-terminal valine while the beta chain had a mol. wt. of 59000 and had N-terminal lysine. All carbohydrate resided in the beta subunit. Incomplete cleavage of the 5-methionine residues of the alpha chain enabled a preliminary ordering of the CNBr fragments. Automated sequence analysis of the alpha chain was carried out and the sequence determined was Val-Phe-Asx-Pro-Arg-Arg-Lys-Leu-Glx-Phe-Ala-Leu-Leu-Phe-Leu-Val-Phe-Asx-Glx-Asx-Glx.


Assuntos
Ceruloplasmina , Sequência de Aminoácidos , Aminoácidos/análise , Ceruloplasmina/isolamento & purificação , Ceruloplasmina/metabolismo , Brometo de Cianogênio , Humanos , Substâncias Macromoleculares , Peso Molecular , Nefrose/metabolismo , Fragmentos de Peptídeos/análise
18.
Biochim Biophys Acta ; 1237(1): 95-8, 1995 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-7619848

RESUMO

We have isolated the vma-4 gene, which encodes a 25,746 Dalton subunit of the vacuolar ATPase, from Neurospora crassa. The gene contains two introns and was mapped to the left arm of linkage group I. Comparison of the predicted amino acid sequence with homologous proteins from Saccharomyces cerevisiae, Manduca sexta, and Bos taurus showed only 25% sequence identity. However, computer-assisted predictions of secondary structures gave similar results for all four proteins. Analysis of the sequence and the available biochemical data indicated that the vma-4 gene product may play the same structural role in the vacuolar ATPase as does the gamma-subunit in F-type ATPases.


Assuntos
Adenosina Trifosfatases/genética , Proteínas Fúngicas/genética , Neurospora crassa/genética , Adenosina Trifosfatases/química , Sequência de Aminoácidos , Sequência de Bases , Proteínas Fúngicas/química , Dados de Sequência Molecular , Estrutura Secundária de Proteína , ATPases Translocadoras de Prótons/química , Homologia de Sequência de Aminoácidos
19.
Biochim Biophys Acta ; 512(1): 13-28, 1978 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-151557

RESUMO

A comparative study has been made of the effects of a variety of inhibitors on the plasma membrane ATPase and mitochondrial ATPase of Neurospora crassa. The most specific inhibitors proved to be vanadate and diethylstilbestrol for the plasma membrane ATPase and azide, oligomycin, venturicidin, and leucinostatin for mitochondrial ATPase. N,N'-Dicyclohexylcarbodiimide, octylguanidine, triphenylsulfonium chloride, and quercetin and related bioflavonoids inhibited both enzymes, although with different concentration dependences. Other compounds that were tested (phaseolin, fusicoccin, deoxycorticosterone, alachlor, salicyclic acid, N-1-napthylphthalamate, triiodobenzoic acid, cyclic AMP, cyclic GMP, theobromine, theophylline, and histamine) had no significant effect on either enzyme. Overall, the results indicate that the plasma membrane and mitochondrial ATPases are distinct enzymes, in spite of the fact that they may play related roles in H+ transport across their respective membranes.


Assuntos
Adenosina Trifosfatases/antagonistas & inibidores , Membrana Celular/enzimologia , Mitocôndrias/enzimologia , Neurospora crassa/enzimologia , Neurospora/enzimologia , Antibacterianos/farmacologia , Azidas/farmacologia , Dicicloexilcarbodi-Imida/farmacologia , Dietilestilbestrol/farmacologia , Guanidinas/farmacologia , Cinética , Oligomicinas/farmacologia , Quercetina/farmacologia , Vanádio , Venturicidinas/farmacologia
20.
Biochim Biophys Acta ; 1132(2): 168-76, 1992 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-1382606

RESUMO

Transgenic mice provide a means to study human gene expression in vivo throughout the aging process. A DNA sequence containing 668 bp of the 5' regulatory region of the human transferrin gene was fused to the bacterial reporter gene chloramphenicol acetyl transferase (TF-CAT) and introduced into the mouse genome. Expression of the human chimeric transferrin gene was similar to the tissue patterns of mouse and human transferrin. In aging transgenic mice, expression of the human chimeric transferrin gene was found to diminish 40% in livers between 18 and 26 months of age. Transferrin levels and serum iron levels in aging humans also diminish, as observed from measurements of total iron binding capacity and percent iron saturation in sera from 701 individuals ranging from 0 to 99 years of age. In contrast, in transgenic mice and nontransgenic mice, the mouse endogenous plasma transferrin and endogenous Tf mRNA increase significantly during aging. Neither the decrease of human TF-CAT nor the increase of mouse transferrin during aging appears to be part of a typical inflammatory reaction. Although the 5' regions of the human transferrin and mouse transferrin genes are homologous, sequence diversities exist which could account for the different responses to inflammation and aging observed.


Assuntos
Envelhecimento/genética , Transferrina/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/metabolismo , Animais , Criança , Pré-Escolar , Cloranfenicol O-Acetiltransferase/genética , Clonagem Molecular , Feminino , Regulação da Expressão Gênica , Humanos , Imunoeletroforese , Lactente , Recém-Nascido , Ferro/sangue , Ferro/metabolismo , Fígado/metabolismo , Masculino , Camundongos , Camundongos Transgênicos , Pessoa de Meia-Idade , RNA/metabolismo , Transferrina/metabolismo
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