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1.
Public Health Pract (Oxf) ; 4: 100293, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36570402

RESUMO

Objectives: The aim of this mixed-method study was to explore maintenance of physical activity and health effects one year after completion of exercise interventions in transport and leisure-time domains of everyday life. We hypothesised that routinisation of active commuting would lead to better maintenance of physical activity and health effects compared with leisure-time exercise. Study design: Mixed-methods follow-up study. Methods: Individuals with overweight/obesity, who completed a 6-month exercise intervention (active commuting by bike (BIKE), moderate (MOD) or vigorous intensity leisure-time exercise (VIG)), were after one year invited to participate in a follow-up visit which included measurements of cardiorespiratory fitness during an incremental bicycle test and body composition using dual-energy X-ray absorptiometry. Variability in maintenance practices was assessed in a sub-sample of participants who experienced the greatest improvements ('VO2peak improvers') and reductions ('VO2peak reducers'), respectively, in cardiorespiratory fitness. Semi-structured interviews were conducted (15-30 min) and analysed using systematic text condensation to identify barriers and facilitators associated with maintenance of physical activity. Results: Out of the 74 participants completing an exercise intervention, 46 (62%) completed follow-up (BIKE: n = 14; MOD: n = 14; VIG: n = 18). Improvements in VO2peak and reductions in fat mass were maintained in BIKE and VIG. Body weight decreased in BIKE and fat free mass increased in VIG. Changes in VO2peak and anthropometry at follow-up did not differ between BIKE and MOD + VIG. Fat mass decreased and recreational physical activity increased in 'VO2peak improvers'. Findings from the interviews suggested that self-monitoring, collective exercising, and new personal exercise challenges facilitate maintenance of a physically active lifestyle. Conclusion: Completion of a structured exercise intervention consisting of 6 months of active commuting or vigorous intensity leisure-time exercise was associated with long-term maintenance of improvements in VO2peak and body composition, whereas moderate intensity leisure-time exercise was not. In contrast to our hypothesis, active commuting was not associated with better maintenance of physical activity and health effects after the intervention compared with leisure-time exercise.

2.
Eur Neuropsychopharmacol ; 59: 82-92, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35561540

RESUMO

The ongoing Coronavirus Disease (COVID-19) pandemic has so far affected more than 500 million people. Lingering fatigue and cognitive difficulties are key concerns because they impede productivity and quality of life. However, the prevalence and duration of neurocognitive sequelae and association with functional outcomes after COVID-19 are unclear. This longitudinal study explored the frequency, severity and pattern of cognitive impairment and functional implications 1 year after hospitalisation with COVID-19 and its trajectory from 3 months after hospitalisation. Patients who had been hospitalised with COVID-19 from our previously published 3-months study at the Copenhagen University Hospital were re-invited for a 1-year follow-up assessment of cognitive function, functioning and depression symptoms. Twenty-five of the 29 previously assessed patients (86%) were re-assessed after 1 year (11±2 months). Clinically significant cognitive impairments were identified in 48-56 % of patients depending on the cut-off, with verbal learning and executive function being most severely affected. This was comparable to the frequency of impairments observed after 3 months. Objectively measured cognitive impairments scaled with subjective cognitive difficulties, reduced work capacity and poorer quality of life. Further, cognitive impairments after 3 months were associated with the severity of subsequent depressive symptoms after 1 year. In conclusion, the stable cognitive impairments in approximately half of patients hospitalized with COVID-19 and negative implications for work functioning, quality of life and mood symptoms underline the importance of screening for and addressing cognitive sequelae after severe COVID-19.


Assuntos
COVID-19 , Disfunção Cognitiva , COVID-19/complicações , Disfunção Cognitiva/etiologia , Hospitalização , Humanos , Estudos Longitudinais , Qualidade de Vida
3.
J Affect Disord ; 289: 125-134, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-33979722

RESUMO

BACKGROUND: The International Society for Bipolar Disorders Targeting Cognition Task Force recommends the Screen for Cognitive Impairment in Psychiatry (SCIP) to screen for cognitive impairment in bipolar disorder. However, SCIP must be administered by a healthcare professional, which is often impossible due to time and resource constraints. Web-based, self-administered cognition screening tools may enable assessment and monitoring of patients' cognition at a much larger scale to a reduced cost. For this purpose, we developed the Internet-Based Cognitive Assessment Tool (ICAT) as a modified web-based version of SCIP. This study aimed to investigate the sensitivity and validity of ICAT for cognition assessment in bipolar disorder. METHOD: Thirty-five patients with bipolar disorder in full or partial remission and 35 healthy controls completed ICAT on a computer, the standard paper-and-pencil SCIP and a subjective cognition questionnaire and were rated for mood symptoms and functioning at the Copenhagen Affective Disorders Research Centre. RESULTS: Patients displayed cognitive impairments compared to controls on the ICAT (t (61)=3.67, p<.001, d=0.93). There was a strong correlation between ICAT and SCIP Total Scores (r(61)=.72, p<.000) and moderate to strong correlations on subtest scores (r=.48-.63, ps<.001). Across all participants, lower ICAT scores correlated with more subjective cognitive complaints (r(59)=-.43, p<.001) and poorer psychosocial functioning (r(62)=-.47, p<.001). CONCLUSION: ICAT is a sensitive and valid web-based tool for cognition assessment in patients with bipolar disorder. This highlights ICAT as a novel web-based cognition screening tool that is feasible for largescale assessment and monitoring of cognition in the clinical management of bipolar disorder.


Assuntos
Transtorno Bipolar , Transtornos Cognitivos , Transtorno Bipolar/diagnóstico , Cognição , Humanos , Internet , Testes Neuropsicológicos
4.
BMC Vet Res ; 13(1): 135, 2017 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-28532438

RESUMO

BACKGROUND: Individual differences of mink, including color type, are speculated to affect the course of wound healing, thereby impacting wound assessment and management on the farms, as well as the assessment of wounds in forensic cases. In this study, we examined the effect of color type on early wound healing in farmed mink. Full thickness excisional wounds (2 × 2 cm) were made on the back in 18 mink of the color types Brown, Silverblue and Blue Iris. Gross and microscopic pathology of the wounds was evaluated 2 days post-wounding together with degree of wound size reduction, presence of bacteria and blood analyses. RESULTS: Pathological examination on day 2 showed the greatest mean wound size reduction in Brown mink (11.0%) followed by Blue Iris (7.9%) and Silverblue (1.6%). Bacteria were cultured from all wounds, and predominantly Staphylococcus species were recovered in mixed or pure culture. Histopathology from day 2 wounds showed a scab overlying necrotic wound edges, which were separated from underlying vital tissue by a demarcation zone rich in polymorphonuclear leukocytes. Fibroblasts and plump endothelial cells were more numerous in the deeper tissues. Complete blood count parameters were within normal ranges in most cases, however, the mink showed mildly to markedly decreased hematocrit and six mink of the color types Silverblue and Blue Iris showed moderately elevated numbers of circulating segmented neutrophils on day 2. There was a marked increase in concentration of serum amyloid A from day 0 to day 2 in all color types. CONCLUSIONS: We have described differences in early wound healing between mink of the color types Brown, Silverblue and Blue Iris by use of an experimental wound model in farmed mink. The most pronounced difference pertained to the degree of wound size reduction which was greatest in Brown mink, followed by Blue Iris and Silverblue, respectively.


Assuntos
Cor de Cabelo , Vison , Cicatrização , Ferimentos e Lesões/veterinária , Animais , Masculino , Ferimentos e Lesões/microbiologia , Ferimentos e Lesões/patologia
5.
Vet Pathol ; 53(3): 666-73, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26333293

RESUMO

The aim of this study was to evaluate gross and histologic lesions and epidemiologic factors of foot lesions in farmed mink. The feet of 1159 mink from 4 Danish farms were examined and lesions described. Swabs from the lesions were taken from 27 mink for microbiology, and tissue samples from a representative spectrum of feet with and without lesions (n= 22) were examined histologically. Feet were grouped according to gross inspection: no lesions (55.1%), hair loss (7.1%), hyperkeratosis (35.8%), and crusting (5.3%). Lesions were predominantly located in plantar metatarsal skin (98.1%). Staphylococci were the most prevalent microorganisms cultured from the lesions. There was a significant association between presence of lesions and sex (P< .0001), age (P< .0001), and color type (P= .023). Lesion size was significantly different between hair loss and crusts and between hyperkeratosis and crusts (P< .0001). Histologically, lesions included varying degrees of orthokeratotic to parakeratotic hyperkeratosis and granulomatous to pyogranulomatous dermatitis with trichogranulomas as a dominant feature in all mink. The gross and microscopic lesions were comparable to physically induced changes in other species that develop as a response to repetitive friction or pressure. The condition may have an impact on animal welfare in mink production.


Assuntos
Doenças do Pé/veterinária , Vison , Animais , Estudos Transversais , Dinamarca/epidemiologia , Fazendas , Feminino , Pé/patologia , Doenças do Pé/epidemiologia , Doenças do Pé/patologia , Masculino
6.
J Dairy Sci ; 98(4): 2389-400, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25648820

RESUMO

The right brain hemisphere, connected to the left eye, coordinates fight and flight behaviors in a wide variety of vertebrate species. We investigated whether left eye vision predominates in dairy cows' interactions with other cows and humans, and whether dominance status affects the extent of visual lateralization. Although we found no overall lateralization of eye use to view other cows during interactions, cows that were submissive in an interaction were more likely to use their left eye to view a dominant animal. Both subordinate and older cows were more likely to use their left eye to view other cattle during interactions. Cows that predominantly used their left eye during aggressive interactions were more likely to use their left eye to view a person in unfamiliar clothing in the middle of a track by passing them on the right side. However, a person in familiar clothing was viewed predominantly with the right eye when they passed mainly on the left side. Cows predominantly using their left eyes in cow-to-cow interactions showed more overt responses to restraint in a crush compared with cows who predominantly used their right eyes during interactions (crush scores: left eye users 7.9, right eye users 6.4, standard error of the difference=0.72). Thus, interactions between 2 cows and between cows and people were visually lateralized, with losing and subordinate cows being more likely to use their left eyes to view winning and dominant cattle and unfamiliar humans.


Assuntos
Comportamento Animal/fisiologia , Bovinos/fisiologia , Lateralidade Funcional/fisiologia , Visão Ocular/fisiologia , Agressão , Animais , Reação de Fuga , Feminino , Humanos , Relações Interpessoais
8.
Hum Reprod ; 26(8): 2129-39, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21572085

RESUMO

BACKGROUND: Conflicting results of studies on mouse and human have either verified or refuted the presence of oogonia/primordial germ cells in the post-natal ovary. The aim of this study was to trace whether oogonia recognized by immunohistochemical methods in the first trimester human ovary were present also in peri- and post-natal ovaries. METHODS: For this study, 82 human ovaries were collected: 25 from embryos from 5 to 10 weeks post conception (wpc), 2 at 18 wpc, 32 from 32 wpc to 2 years and 23 from 2 to 32 years. Of these, 80 ovaries were fixed and paraffin-embedded and 2 (8 year-old) ovaries were processed for plastic sections. Serial sections were prepared for immunohistochemical detection of markers for oogonia: tyrosine kinase receptor for stem cell factor (SCF)(C-KIT), stage-specific embryonic antigen-4 (SSEA4), homeobox gene transcription factor (NANOG), octamer binding transcription factor 4 (OCT4) and melanoma antigen-4 (Mage-A4), while noting that C-KIT also stains diplotene oocytes. RESULTS: Almost all oogonia exclusively stained for SSEA4, NANOG, OCT4 and C-KIT, whereas MAGE-A4 only stained a small fraction. At birth only a few oogonia were stained. These disappeared before 2 years, leaving only diplotene oocytes stained for C-KIT. From 18 wpc to 2 years, the medulla contained conglomerates of healthy and degenerating oogonia and small follicles, waste baskets (WBs) and oogonia enclosed in growing follicles (FWB). Medulla of older ovaries contained groups of primordial, healthy follicles. CONCLUSIONS: We found no evidence for the presence of oogonia in the human ovary after their final clearing during the first 2 years. We suggest that perinatal medullary WB and FWB give rise to the groups of small, healthy follicles in the medulla.


Assuntos
Ovário/embriologia , Ovário/crescimento & desenvolvimento , Adulto , Antígenos de Neoplasias/análise , Criança , Pré-Escolar , Feminino , Proteínas de Homeodomínio/análise , Humanos , Lactente , Proteína Homeobox Nanog , Proteínas de Neoplasias/análise , Fator 3 de Transcrição de Octâmero/análise , Oogônios , Ovário/metabolismo , Gravidez , Primeiro Trimestre da Gravidez , Proteínas Proto-Oncogênicas c-kit/análise , Antígenos Embrionários Estágio-Específicos/análise
9.
Curr Med Res Opin ; 26(8): 2041-5, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20597596

RESUMO

UNLABELLED: In all, 19-22% of the adult Danish population suffer from chronic pain - most frequently in the musculoskeletal system. Different pain management strategies depending on pain mechanism (neuropathic/nociceptive) make diagnosing the pain condition especially important. OBJECTIVES: To investigate whether a validated, self-administered questionnaire (PainDETECT) helps specialists and general practitioners in Denmark identify patients with neuropathic pain components (NeP). RESEARCH DESIGN AND METHODS: In a non-interventional study a sample of Danish specialists (rheumatologists and anaesthesiologists) and general practitioners used the PainDETECT questionnaire on 1322 chronic pain patients. PainDETECT was filled in by patients and scored by the physician. A PainDETECT score above 18 indicates the presence of NeP. RESULTS: A total of 87-95% of the included chronic pain patients (702 by specialists (mean age: 56 years) and 620 by general practitioners (mean age: 55 years)) had musculoskeletal pain. In 39-43% of these patients NeP components were present as assessed by PainDETECT (score 21.1-21.7). One-third of the 540 NeP patients (31-36%) had their pain diagnosis reclassified from a non-NeP to a predominant/mixed NeP diagnosis after use of PainDETECT. CONCLUSIONS: Neuropathic pain seems to be underdiagnosed in musculoskeletal pain conditions. Use of the PainDETECT instrument may be of help to general practitioners and specialists when diagnosing NeP in chronic pain patients. However, the fact that no neurologists were included, together with the limited sample size, with large variations in the number of patients each physician included, as well as the lack of a strict consecutive recruitment process are study limitations.


Assuntos
Doenças Musculoesqueléticas/diagnóstico , Doenças Musculoesqueléticas/epidemiologia , Neuralgia/diagnóstico , Neuralgia/epidemiologia , Inquéritos e Questionários , Doença Crônica , Estudos Transversais , Dinamarca/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nociceptores , Reprodutibilidade dos Testes , Inquéritos e Questionários/normas
10.
Mol Hum Reprod ; 16(9): 621-31, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20566702

RESUMO

The aim of this study was to investigate the spatiotemporal development of autonomic nerve fibers and primordial germ cells (PGCs) along their migratory route from the dorsal mesentery to the gonadal ridges in human embryos using immunohistochemical markers and electron microscopy. Autonomic nerve fibers in the dorsal mesentery, the pre-aortic and para-aortic plexuses and in the gonadal ridge were stained for beta III tubulin, neuron specific enolase and the glia fibrillary acidic protein. Electron microscopy demonstrated the presence of neurofilaments and neurotubules in these nerve fibers and their intimate contact with PGCs. PGCs expressed GAGE, MAGE-A4, OCT4 and c-Kit. Serial paraffin sections showed that most PGCs were located inside bundles of autonomic nerve fibers with the majority adjacent to the most peripheral fibers (close to Schwann cells). We also show that both nerve fibers and PGCs arrive at the gonadal ridge between 29 and 33 days pc. In conclusion, our data suggest that PGCs in human embryos preferentially migrate along autonomic nerve fibers from the dorsal mesentery to the developing gonad where they are delivered via a fine nerve plexus.


Assuntos
Sistema Nervoso Autônomo/embriologia , Movimento Celular , Células Germinativas/fisiologia , Gônadas/embriologia , Mesentério/embriologia , Fibras Nervosas/fisiologia , Células de Schwann/fisiologia , Sistema Nervoso Autônomo/química , Sistema Nervoso Autônomo/ultraestrutura , Biomarcadores/análise , Feminino , Células Germinativas/química , Células Germinativas/ultraestrutura , Idade Gestacional , Gônadas/química , Gônadas/ultraestrutura , Humanos , Imuno-Histoquímica , Mesentério/química , Mesentério/ultraestrutura , Microscopia Eletrônica , Fibras Nervosas/química , Fibras Nervosas/ultraestrutura , Ovário/embriologia , Células de Schwann/química , Células de Schwann/ultraestrutura
11.
J Morphol ; 262(2): 583-607, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15376276

RESUMO

This study deals with the morphology and ultrastructure of the mesonephros in adult caecilians of the species Geotrypetes seraphini. Based on serial sections in paraffin and araldite, nephrons are reconstructed and the cellular characteristics of different nephron segments described. The long and slender mesonephric kidneys of G. seraphini are broadest caudally and taper toward the front, where the organs are divided into smaller segmental divisions. Two nephron types can be distinguished on the basis of their connections to the coelom and their position within the nephric tissue: ventral nephrons connect to the coelom via a ciliated peritoneal funnel, whereas medial nephrons lack this connection. Both nephron types are composed of a filtration unit, the Malpighian corpuscle, and a renal tubule, which can be divided into six morphologically distinct segments: neck segment, proximal tubule, intermediate segment, early distal tubule, late distal tubule, and collecting tubule. Collecting tubules merge and form a branch system that opens into collecting ducts. Collecting ducts empty into the Wolffian duct. Proximal tubules of nephrons in the frontal divisions are morphologically different from the proximal tubules of more caudal kidney regions. Distal tubule subdivision is only clearly recognizable at the electron microscopic level. The length of each nephron segment is calculated from a ventral nephron with a total length of approximately 3.8 mm, and the course of the segments within the nephric tissue is reported. The number of nephrons was estimated at 1,700 units in each kidney. The segmentation and ultrastructure of the mesonephric nephrons in G. seraphini are discussed in relation to nephron descriptions from other caecilians and we further discuss the evolutionary origin of the amphibian nephron.


Assuntos
Anfíbios/anatomia & histologia , Rim/anatomia & histologia , África Ocidental , Animais , Evolução Biológica , Feminino , Rim/ultraestrutura , Glomérulos Renais/anatomia & histologia , Glomérulos Renais/ultraestrutura , Microscopia , Microscopia Eletrônica de Transmissão , Néfrons/anatomia & histologia , Néfrons/ultraestrutura , Especificidade da Espécie
12.
Biologicals ; 29(2): 97-106, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11580214

RESUMO

A preparation of somatropin (recombinant DNA-derived human growth hormone) was prepared as lyophilised ampoules according to WHO procedures for international biological standards. The candidate preparation (98/574) was evaluated in an international collaborative study (16 laboratories, nine countries), with the following aims: (i) to determine the suitability of the preparation to serve as the International Standard for somatropin by studying its performance in the current range of physico-chemical and biological assay methods employed for somatropin; (ii) to assign a content in terms of the existing (first) International Standard for somatropin, using the currently recognised assay procedure (Size Exclusion High Performance Liquid Chromatography, SE HPLC); (iii) to confirm the specific biological activity of the candidate preparation; (iv) to confirm the stability of the candidate preparation. On the basis of the collaborative study WHO agreed that: the preparation in ampoules coded 98/574 is suitable to serve as the next WHO International Standard for somatropin; the preparation in ampoules coded 98/574 should be established as the second International Standard for somatropin, with a defined ampoule content of 1.95 mg total somatropin plus somatropin-related proteins per ampoule; the specific activity of the preparation should be defined as 3.0 IU/mg somatropin.


Assuntos
Hormônio do Crescimento Humano/normas , Cromatografia Líquida de Alta Pressão , Hormônio do Crescimento Humano/análise , Hormônio do Crescimento Humano/isolamento & purificação , Humanos , Cooperação Internacional , Padrões de Referência , Organização Mundial da Saúde
13.
Artigo em Inglês | MEDLINE | ID: mdl-11913465

RESUMO

Evidence is discussed that apical CFTR Cl- channels of mitochondria-rich (MR) cells of Bufo bufo skin conduct beta-adrenergic receptor-activated Cl- currents. Ussing chambers studies revealed the following selectivity sequence of the receptor activated conductance, Cl- > Br- > NO3- > I-. With ion selective microelectrode-techniques, it was shown that receptor-coupled Cl- channels are not located in principal cells. A small conductance (7-10 pS) CFTR-like Cl- channel is located in the apical plasma membrane of MR cells. Short life times of sealed patches prevented detailed study of its selectivity to other halide ions and its molecular regulation. With monoclonal hCFTR-antibodies, selective expression in MR cells of the targeted antigens could be demonstrated. A transcript of CFTR was amplified in the skin, and a bbCFTR cDNA clone was generated from toad skin mRNA that exhibits 89% amino acid identity with the human homologue. The frequency of obtaining channels in patch clamp studies was too low for accounting quantitatively for the macroscopic conductance. Since MR cells were isolated by trypsin, and a putative extracellular loop of the deduced bbCFTR protein contains a target peptide bond for trypsin, enzyme treatment may have destroyed apical CFTR molecules.


Assuntos
Cloretos/metabolismo , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Pele/metabolismo , Sequência de Aminoácidos , Animais , Bufo bufo , Clonagem Molecular , Regulador de Condutância Transmembrana em Fibrose Cística/química , Regulador de Condutância Transmembrana em Fibrose Cística/genética , DNA Complementar , Humanos , Transporte de Íons , Microscopia Eletrônica , Dados de Sequência Molecular , Técnicas de Patch-Clamp , Receptores Adrenérgicos beta/efeitos dos fármacos , Receptores Adrenérgicos beta/metabolismo , Homologia de Sequência de Aminoácidos , Pele/ultraestrutura
14.
J Morphol ; 245(3): 177-95, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10972968

RESUMO

This study deals primarily with the morphology and ultrastructure of the pronephros in the green toad Bufo viridis during prometamorphosis when the pronephros and the developing mesonephros function simultaneously. Furthermore, the mesonephros was studied during pro- and postmetamorphosis with emphasis on the distal segments of the nephron. The paired kidneys consist of two cranial pronephroi immediately behind the gill region and two more caudal elongated mesonephroi. Each pronephros consists of a single convoluted tubule which opens into the coelom via three nephrostomes. This tubule is divided into three ciliated tubules, three proximal tubule branches, a common proximal tubule and a distal tubule, which in turn continues into the nephric duct. No intermediate segment is present. The length of the pronephric tubule is 12 mm, including the three branches of the ciliated tubules and proximal tubules. Primary urine is formed upon filtration from an external glomerulus, which is a convoluted capillary lined by podocytes, a specialization of the coelomic epithelium. From the coelom the filtrate is swept into the ciliated tubules. In the collecting duct system of the developing mesonephric nephron epithelial cells with conspicuous, apical osmiophilic granules appear in larvae of 9-10 mm. Heterocellularity of mixed intercalated (mitochondria rich) cells and principal cells is observed in the collecting duct system and nephric duct from a larval body length of 14 mm. As the proliferation of mitochondria-rich cells proceeds, the osmiophilic granules disappear and are completely absent from the adult amphibian mesonephros.


Assuntos
Bufonidae/anatomia & histologia , Rim/anatomia & histologia , Animais , Rim/ultraestrutura , Glomérulos Renais/anatomia & histologia , Glomérulos Renais/ultraestrutura , Túbulos Renais/anatomia & histologia , Túbulos Renais/ultraestrutura , Larva/anatomia & histologia
15.
J Exp Biol ; 203(Pt 2): 171-81, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10607527

RESUMO

Nonylphenol has been found to exert estrogenic effects in fish and may influence the fertility of male fish. In the present study, the effects of nonylphenol and 17beta-estradiol on vitellogenin synthesis and testis morphology in platyfish Xiphophorus maculatus were investigated. Vitellogenin was observed in the plasma of all fish exposed to nonylphenol or 17beta-estradiol. Exposure to 17beta-estradiol resulted in a significant reduction in the gonadosomatic index. A tendency for a dose-dependent reduction in the gonadosomatic index in the nonylphenol exposed groups was observed. Histological examination revealed dose-dependent effects of nonylphenol on the testis structure. The testes of control fish contained numerous cysts with spermatogenetic cells. The testes of fish exposed to nonylphenol or 17beta-estradiol showed a decrease in the number of cysts concomitant with an increase in the amount of hypertrophied Sertoli cells present. Formation of spermatozeugmata is compulsory for this species, but free spermatozoa were observed in the efferent ducts of the treated fish. The study indicates that nonylphenol has estrogenic potency, and that both nonylphenol and 17beta-estradiol have marked effects on the testis morphology of X. maculatus. The ambient concentration of nonylphenol was measured by high pressure liquid chromatography during the experiment. The measurements revealed that the actual concentrations of nonylphenol in the water were about 30-40 % of the nominal concentrations.


Assuntos
Ciprinodontiformes/anatomia & histologia , Congêneres do Estradiol/toxicidade , Estradiol/toxicidade , Fenóis/toxicidade , Testículo/efeitos dos fármacos , Vitelogeninas/biossíntese , Animais , Ciprinodontiformes/metabolismo , Eletroforese em Gel de Poliacrilamida , Masculino , Microscopia Eletrônica , Células de Sertoli/efeitos dos fármacos , Células de Sertoli/metabolismo , Células de Sertoli/ultraestrutura , Testículo/anatomia & histologia , Testículo/metabolismo , Testículo/ultraestrutura , Poluentes da Água/efeitos adversos , gama-Glutamiltransferase/metabolismo
16.
J Exp Biol ; 201(Pt 2): 179-92, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9405301

RESUMO

Nonylphenol has been found to be oestrogenic in fish and may influence the reproductive system of male fish. In the present study, the effects of low (10 microg g-1 week-1) and high (100 microg g-1 week-1) doses of nonylphenol and of 17 beta-oestradiol on the synthesis of vitellogenin and on testicular structure and cytology were investigated in male eelpout Zoarces viviparus during active spermatogenesis (May) and late spermatogenesis (June). Twenty-five days after injection, a significant dose-dependent increase in the plasma vitellogenin concentration, measured by enzyme-linked immunosorbent assay, was observed in the treated groups. A highly significant reduction in the gonadosomatic index was observed concomitant with the increase in the plasma vitellogenin concentration. Macroscopically, milt was observed to be present in the control fish, but was sparse or absent in the treated fish. Histological examination using light microscopy revealed severe effects of nonylphenol as well as of oestradiol treatment on testicular structure. Control fish had seminiferous lobules containing spermatogenic cysts and only a few spermatozoa (May) or had the walls of their seminiferous lobules lined with cuboidal Sertoli cells (June). In the treated fish, the seminiferous lobules were degenerated (May) or were filled with numerous spermatozoa and the Sertoli cells appeared very squamous (June). Electron microscopy revealed greater numbers of phagocytosed spermatozoa in these Sertoli cells. In rats, -glutamyl transpeptidase (-GTP) has been used as a specific marker of Sertoli cell function. In the present study, both nonylphenol and 17 beta-oestradiol treatment resulted in a reduction in the activity of this enzyme. The study provides evidence that nonylphenol is oestrogenic, as indicated by the large increase in vitellogenin synthesis, and that both nonylphenol and oestradiol have marked effects on the testicular structure and cytology of germ cells and Sertoli cells of male Z. viviparus.


Assuntos
Estradiol/administração & dosagem , Fenóis/administração & dosagem , Testículo/efeitos dos fármacos , Vitelogeninas/biossíntese , Animais , Ativação Enzimática/efeitos dos fármacos , Peixes , Injeções Intraperitoneais , Masculino , Tamanho do Órgão/efeitos dos fármacos , Testículo/enzimologia , Testículo/ultraestrutura , Vitelogeninas/efeitos dos fármacos , gama-Glutamiltransferase/análise
17.
Eur J Biochem ; 235(1-2): 304-9, 1996 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-8631346

RESUMO

The amino acid sequence Asn-Gly has at pH 7 a tendency to induce deamidation of asparagine to aspartic acid via the formation of a cyclic imide. This imide opens up to yield Asp-Gly or the isoaspartic acid (isoAsp) form, isoAsp-Gly. Both isomers may be found in their L-form or D-form. Like Asn-Gly, the sequence Asp-Gly has a tendency for isomerization and racemization via the formation of a cyclic imide intermediate. When human growth hormone is digested with trypsin, one of the fragments is a heptapeptide (amino acid residues 128-134) containing the amino acid sequence Asp-Gly (amino acid residues 130 and 131). This heptapeptide, as well as stereoisomers and isoforms where L-Asp was replaced by D-Asp, L-isoAsp, D-isoAsp or the L-cyclic imide, respectively, has been synthesized and used as a standard to achieve separation of the five forms by capillary electrophoresis and by reverse-phase HPLC. Capillary electrophoresis analysis was performed in uncoated capillaries by the use of aspartic acid/cyclodextrin buffers at low pH. The elution order of the aspartic-acid-containing heptapeptides was D-Asp, L-Asp, L-isoAsp, D-isoAsp and L-cyclic imide. Reverse-phase HPLC analysis was performed on a C18 column by the use of a shallow acetonitrile gradient in trifluoroacetic acid/water. The elution order was D-isoasp, L-isoASp, L-Asp, D-Asp and L-cyclic imide. Human growth hormone samples were degraded by incubation at high temperature and analyzed for their potential content of isomerization and racemization products. Only L-forms of aspartic acid and isoaspartic acid of the heptapeptide fragment were found.


Assuntos
Hormônio do Crescimento/síntese química , Fragmentos de Peptídeos/síntese química , Sequência de Aminoácidos , Cromatografia Líquida de Alta Pressão , Eletroforese Capilar , Hormônio do Crescimento/química , Hormônio do Crescimento/genética , Humanos , Dados de Sequência Molecular , Oligopeptídeos/síntese química , Oligopeptídeos/química , Oligopeptídeos/genética , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/genética , Estereoisomerismo , Tripsina
18.
Eur J Biochem ; 219(1-2): 365-73, 1994 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-8307002

RESUMO

A novel protein derivative has been found during process development of biosynthetic human growth hormone; it has been characterised as human growth hormone with a Cys182-Cys189 trisulphide bridge. We have not been able to find a previous report in the literature about this kind of derivative. The characterisation was obtained partly on the full-length derivative and partly on a tryptic fragment of the derivative. The full-length derivative was characterised by reduction with 1,4-dithiothreitol followed by electrospray mass spectrometry, treatment with cysteine and measurement of hydrogen sulphide liberation upon cysteine treatment. The tryptic fragment from peptide mapping was characterised by amino acid analysis, amino acid sequencing and mass spectrometry. All data indicated an extra sulphur atom in the Cys182-Cys189 cystine bridge.


Assuntos
Clonagem Molecular , Cisteína/metabolismo , Escherichia coli/metabolismo , Hormônio do Crescimento/análogos & derivados , Hormônio do Crescimento/química , Sulfetos/análise , Sequência de Aminoácidos , Cromatografia Líquida de Alta Pressão , Cisteína/análise , Cistina/análise , Cistina/metabolismo , Ditiotreitol , Hormônio do Crescimento/biossíntese , Hormônio do Crescimento/isolamento & purificação , Humanos , Espectrometria de Massas , Dados de Sequência Molecular , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/isolamento & purificação , Mapeamento de Peptídeos , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação
19.
Metabolism ; 42(12): 1503-5, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8246761

RESUMO

A great deal of interest in the element vanadium has been generated recently because of its potential as a therapeutic agent for diabetes mellitus. Vanadium's insulin-mimetic properties and its requirement for proper growth and development suggest that it may be involved in insulin's mechanism of action. We have therefore examined vanadium levels in kidney, muscle, and liver tissues from normal and diabetic BB Wistar rats. Our results indicate that diabetes mellitus can decrease the tissue vanadium content of liver, suggesting that the trace element vanadium may be important in insulin action.


Assuntos
Diabetes Mellitus Tipo 1/metabolismo , Rim/química , Fígado/química , Músculos/química , Vanádio/análise , Animais , Glicemia/análise , Peso Corporal , Diabetes Mellitus Tipo 1/sangue , Insulina/sangue , Rim/metabolismo , Fígado/metabolismo , Músculos/metabolismo , Ratos , Ratos Endogâmicos BB , Valores de Referência , Vanádio/metabolismo
20.
Talanta ; 38(12): 1369-79, 1991 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18965311

RESUMO

Biosynthetic human Growth Hormone (B-hGH) is a protein comprising 191 amino acids. The molecular weight is 22,125 and the isoelectric point is close to pH 5. Due to the ready availability of closely related analogues B-hGH was used as a model protein thus allowing for the demonstration and evaluation of the high resolution capability of high performance capillary electrophoresis (HPCE). The same apparatus was used throughout the experiments and an optimum signal-to-noise ratio was found at 200 nm. Linearity was observed between peak area, retention time and the hGH concentration or sample introduction time. Baseline separation of hGH, desamido hGH and didesamido hGH was obtained. Examples showing analysis with 1 million theoretical plates per meter, high speed separation, simultaneous analysis of multiple samples, sample stacking, hGH tryptic digest, and hGH lysate are reported. The use of electrophoretic velocities instead of apparent velocities for peak identification is illustrated.

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