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2.
J Endocrinol ; 138(3): 451-8, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7506290

RESUMO

Recent observations indicate that the rat ovary receives not only adrenergic but also peptidergic innervation. In ruminants, there are few data available on the extent of a possible direct regulation of the peptidergic innervation of the ovary including the corpus luteum (CL). The direct effects of neuropeptide Y (NPY), substance P (SP) and vasoactive intestinal polypeptide (VIP) on the release of progesterone and oxytocin from midluteal phase CL (days 8-12) were examined in vitro. A possible direct neural influence might provide a sensitive short-term control. Long-term as well as short-term effects were assessed using both a serum-reduced luteal cell culture and a microdialysis system (MDS) of luteal tissue. In the long-term experiments, luteal cells were preincubated from the start of the culture for 48 h with NPY, SP and VIP (10 pmol/1-100 nmol/l). During the following 4 h the neuropeptides showed a dose-dependent stimulation of progesterone release, but there was no effect on oxytocin release. LH showed a synergistic effect with NPY, SP and VIP on progesterone release. In the short-term experiments, the neuropeptides were added 48 h after the start of the culture. All three peptides were most stimulatory to LH-supported progesterone release 30 min after addition, and the effect decreased greatly thereafter to the control level from 60 to 120 min. In contrast, LH alone induced the maximal progesterone stimulation at 120 min. In the MDS, a 30-min perfusion with NPY, SP or VIP (10 nmol/l, 100 nmol/l and 1 mumol/l) induced significant acute effects on progesterone and oxytocin release.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Bovinos/metabolismo , Corpo Lúteo/efeitos dos fármacos , Neuropeptídeos/farmacologia , Ocitocina/metabolismo , Progesterona/metabolismo , Animais , Células Cultivadas , Corpo Lúteo/metabolismo , Relação Dose-Resposta a Droga , Feminino , Neuropeptídeo Y/farmacologia , Substância P/farmacologia , Fatores de Tempo , Peptídeo Intestinal Vasoativo/farmacologia
3.
Domest Anim Endocrinol ; 18(2): 187-97, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10764975

RESUMO

The aim of the study was to investigate the influence of diarrheic infections during the early postnatal phase of calves on the concentrations of hormones controlling reproduction and metabolism. Blood samples were collected from 20 male and female calves via jugular vein catheters every 15 min for 6 hr at Days 3, 9, and 21 of life. The animals were classified into three groups. Group 1 (controls): healthy calves (n = 9). Group 2: calves affected with diarrhea at Day 9 (n = 7). Group 3: calves with diarrhea at Days 3 and 9 (n = 4). Infections occurred spontaneously and were mainly due to E. coli infections. All affected calves had recovered at Day 21. Mean GH concentrations in the calves in Groups 2 and 3 compared to control calves had increased by Day 3 (P<0.01; P<0.001). Cortisol levels of calves in all groups were highest at Day 3 and decreased thereafter (P<0.001). Cortisol concentrations were lower at Day 3 in animals in Groups 2 (P<0.001) and 3 (P<0.05) than in controls. Pulsatile LH release was detectable at Days 9 and 21 only in healthy calves. Insulin increased at Day 9 during diarrhea. The results indicate that cortisol concentrations decreased whereas GH concentrations were increased before diarrhea was observed. The onset of pulsatile LH release was delayed in diarrheic calves. It is concluded that diarrhea exerts effects upon the release of reproductive and metabolic hormones in early postnatal calves.


Assuntos
Doenças dos Bovinos/sangue , Diarreia/veterinária , Hormônio do Crescimento/sangue , Insulina/sangue , Hormônio Luteinizante/sangue , Fatores Etários , Ração Animal , Animais , Bovinos , Diarreia/sangue , Feminino , Masculino , Radioimunoensaio/veterinária
4.
Comput Biol Med ; 30(3): 153-69, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10758230

RESUMO

Selective Image Compression (SeLIC) is a compression technique where explicitly defined regions of interest (RoI) are compressed in a lossless way whereas image regions containing unimportant information are compressed in a lossy manner. Such techniques are of great interest in telemedicine or medical imaging applications with large storage requirements. In this paper we introduce and compare techniques with different functionalities. Moreover, we investigate the impact of using wavelet transforms and JPEG as underlying lossy compression algorithm.


Assuntos
Sistemas de Informação em Radiologia , Telerradiologia , Algoritmos , Gráficos por Computador , Humanos , Software
5.
Artigo em Alemão | MEDLINE | ID: mdl-10384704

RESUMO

After reviewing the relevant literature about the relationship of negative energy balance post partum and the onset of cyclicity the aim of this study will be described. The objective of this trial was to evaluate the influence of negative energy balance on the sensitivity of the pituitary for GnRH. Two groups of Holstein Friesian cows were randomly treated either with GnRH (Fertagyl) or a placebo. Considering the weekly calculated negative energy balance, the reaction of the pituitary was determined by analyzing LH in 16 blood samples, collected every 20 minutes starting one hour before and ending four hours after treatment. All cows treated with GnRH showed an intensive LH-surge, significantly different from the controls. These data suggest, that the sensitivity of the pituitary gland is not directly influenced by negative energy balance. The hypothalamus has the inhibiting priority over the pituitary delaying post partum cyclicity.


Assuntos
Metabolismo Energético/efeitos dos fármacos , Hormônio Liberador de Gonadotropina/farmacologia , Hipófise/fisiologia , Período Pós-Parto/fisiologia , Animais , Bovinos , Feminino , Lactação , Hormônio Luteinizante/sangue , Hormônio Luteinizante/metabolismo , Leite/efeitos dos fármacos , Leite/metabolismo , Hipófise/efeitos dos fármacos , Placebos , Período Pós-Parto/efeitos dos fármacos
6.
Ophthalmologe ; 108(9): 859-62, 2011 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-21688053

RESUMO

This paper presents a case of ocular involvement during acute renal failure caused by hantavirus. A 34-year-old man suffered from sudden visual loss during acute onset fever with nausea and renal failure. The ophthalmologic examination showed myopia in both eyes and no signs of infection but virological studies revealed an infection with hantavirus. During treatment of the renal failure the myopia improved spontaneously. Transient myopia is a typical ocular involvement during infections with hantavirus which leads to renal failure.


Assuntos
Emergências , Infecções por Hantavirus/diagnóstico , Miopia/etiologia , Doença Aguda , Injúria Renal Aguda/etiologia , Adulto , Estudos Transversais , Diagnóstico Diferencial , Alemanha , Infecções por Hantavirus/epidemiologia , Humanos , Incidência , Masculino
7.
Ophthalmologe ; 107(12): 1164-8, 2010 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-20922531

RESUMO

A 69-year-old female patient presented with unilateral optic nerve atrophy and visual loss. The visual field examination showed not only a subtotal visual field loss in the affected eye but also a visual field defect in the other eye which was classified as an anterior junction syndrome. Cranial MRI revealed a tuberculum sellae meningioma which was treated surgically.


Assuntos
Neoplasias Meníngeas/diagnóstico , Meningioma/diagnóstico , Atrofia Óptica/diagnóstico , Transtornos da Visão/diagnóstico , Campos Visuais/fisiologia , Idoso , Diagnóstico Diferencial , Feminino , Humanos , Imageamento por Ressonância Magnética , Neoplasias Meníngeas/fisiopatologia , Neoplasias Meníngeas/cirurgia , Meningioma/fisiopatologia , Meningioma/cirurgia , Microcirurgia , Atrofia Óptica/fisiopatologia , Atrofia Óptica/cirurgia , Retinoscopia , Transtornos da Visão/fisiopatologia , Transtornos da Visão/cirurgia , Acuidade Visual/fisiologia , Testes de Campo Visual
8.
Yeast ; 16(10): 933-44, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10870104

RESUMO

A phosphatidylinositol (PI) 3-kinase gene (CaVPS34) of the human pathogenic yeast Candida albicans was cloned by a PCR-based homology approach. The open reading frame encodes a 1020 amino acid protein with a calculated molecular weight of 118 kDa and a relative isoelectric point of 6.9. It shares 47% sequence identity with Saccharomyces cerevisiae Vps34p. Southern pattern indicated that CaVPS34 is probably present as a single copy gene per haploid genome in C. albicans. We localized the CaVPS34 gene on chromosome 1. Under all conditions tested a major CaVPS34 transcript of approximately 3. 5 kb could be detected. CaVPS34 mRNA levels increased during exponential growth up to 12-fold followed by a decline upon entry into stationary phase. The size of a 6xHis tag-CaVps34p fusion protein purified from Escherichia coli is in agreement with the calculated molecular mass of CaVps34p. It exhibits in vitro PI 3-kinase activity and produces only phosphatidylinositol 3-phosphate. The CaVPS34 gene under the control of its own promoter were not able to complement the temperature-sensitive growth of S. cerevisiae vps34. However, overexpression of CaVPS34 was sufficient to rescue the temperature-sensitive vps34 phenotype, suggesting a functional conservation in C. albicans.


Assuntos
Candida albicans/enzimologia , Clonagem Molecular , Regulação Fúngica da Expressão Gênica , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Sequência de Aminoácidos , Northern Blotting , Southern Blotting , Candida albicans/genética , Candida albicans/crescimento & desenvolvimento , Candidíase/microbiologia , Teste de Complementação Genética , Humanos , Dados de Sequência Molecular , Fosfatidilinositol 3-Quinases/química , Fosfatidilinositol 3-Quinases/isolamento & purificação , RNA Fúngico/isolamento & purificação , Análise de Sequência de DNA
9.
Med Microbiol Immunol ; 186(1): 63-73, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9255768

RESUMO

We report the cloning, sequencing, and analysis of a novel chromosomal gene of Streptococcus equisimilis strain H46A that codes for a membrane lipoprotein, designated LppC. The lppC gene is located 3' adjacent to, and co-oriented with, the unrelated gapC gene that encodes the previously characterized glyceraldehyde-3-phosphate dehydrogenase. Sequencing of lppC revealed an 855-bp open reading frame that predicted a 32.4-kDa polypeptide possessing a potential lipoprotein signal sequence and modification site (VTGC). Signal sequence processing of LppC synthesized in the homologous host or expressed from plasmid pLPP2 in Escherichia coli was sensitive to globomycin, a selective inhibitor of lipoprotein-specific signal peptidase II. Subcellular localization of LppC using polyclonal antibodies raised to the hexahistidyl-tagged protein proved LppC to be tightly associated with the cytoplasmic membrane of S. equisimilis and with the outer membrane of E. coli JM109 (pLPP2). Southern, Northern and Western analyses indicated that lpp was conserved in S. pyogenes, and transcribed independently of gap as monocistronic 0.9-kb mRNA from a sigma 70-like consensus promoter. Database searches found homology of LppC to the hel gene-encoded outer membrane protein e (P4) from Haemophilus influenzae to which it exhibits 58% sequence similarity. However, unlike the hel gene, lppC was unable to complement hemA mutants of E. coli for growth on hemin as sole porphyrin source in aerobic conditions. Furthermore, neither the wild type nor an lppC insertion mutant of S. equisimilis could grow on hemin in iron-limited medium. These results, together with findings indicating that S. equisimilis H46A had no absolute requirement for iron, led us to conclude that lppC, in contrast to hel, is not involved in hemin utilization and has yet to be assigned a function.


Assuntos
Proteínas da Membrana Bacteriana Externa/genética , Genes Bacterianos , Haemophilus influenzae/química , Lipoproteínas/genética , Streptococcus/genética , Sequência de Aminoácidos , Proteínas da Membrana Bacteriana Externa/química , Sequência de Bases , Hemina/farmacologia , Lipoproteínas/química , Dados de Sequência Molecular , Transcrição Gênica
10.
Yeast ; 18(4): 343-53, 2001 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-11223944

RESUMO

A Candida albicans null mutant of the phosphatidylinositol (PI) 3-kinase gene (CaVPS34) involved in virulence was examined by different microscopical techniques. We observed that vacuoles of the Cavps34 null mutant were considerably enlarged and electron-transparent. An interesting result obtained by transmission electron microscopy analysis of Cavps34 mutant cells was the aberrant patch-like accumulation of vesicles, which were localized in the periplasm close to the plasma membrane. We assume that the vesicles result from missorted prevacuolar compartments. In contrast to the accumulations of the specific endocytic dye FM4-64 in the vacuole membrane in C. albicans wild-type strains (ring staining pattern), the Cavps34 mutant strain showed a staining of punctuate structures, possibly multivesicular bodies (MVB), that are scattered all over the cell. This defect indicates a late block in endocytic vesicle transport. Measurement of the total activity of carboxypeptidase Y revealed significantly lower activity in Cavps34 mutant cells. This may indicate that carboxypeptidase Y is not properly activated as a result of mislocalization due to the lack of Vps34p. The deletion of the CaVPS34 gene caused disturbance of normal nuclear migration, which suggests that in the Cavps34 mutant the cell-size mediated control process of cell division is affected.


Assuntos
Candida albicans/genética , Núcleo Celular/genética , Fosfatidilinositol 3-Quinases/genética , Transporte Proteico/genética , Ácidos/metabolismo , Candida albicans/metabolismo , Candida albicans/patogenicidade , Núcleo Celular/patologia , Deleção de Genes , Genes Fúngicos , Hidrolases/metabolismo , Periplasma/metabolismo , Periplasma/patologia , Sinais Direcionadores de Proteínas , Vacúolos/metabolismo , Vacúolos/patologia
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