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1.
Sci Total Environ ; 901: 165933, 2023 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-37536603

RESUMO

An essential prerequisite to safeguard pollinator species is characterisation of the multifaceted diversity of crop pollinators and identification of the drivers of pollinator community changes across biogeographical gradients. The extent to which intensive agriculture is associated with the homogenisation of biological communities at large spatial scales remains poorly understood. In this study, we investigated diversity drivers for 644 bee species/morphospecies in 177 commercial apple orchards across 33 countries and four global biogeographical biomes. Our findings reveal significant taxonomic dissimilarity among biogeographical zones. Interestingly, despite this dissimilarity, species from different zones share similar higher-level phylogenetic groups and similar ecological and behavioural traits (i.e. functional traits), likely due to habitat filtering caused by perennial monoculture systems managed intensively for crop production. Honey bee species dominated orchard communities, while other managed/manageable and wild species were collected in lower numbers. Moreover, the presence of herbaceous, uncultivated open areas and organic management practices were associated with increased wild bee diversity. Overall, our study sheds light on the importance of large-scale analyses contributing to the emerging fields of functional and phylogenetic diversity, which can be related to ecosystem function to promote biodiversity as a key asset in agroecosystems in the face of global change pressures.

2.
Mol Ecol ; 20(22): 4808-21, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21980996

RESUMO

Legume plants can obtain combined nitrogen for their growth in an efficient way through symbiosis with specific bacteria. The symbiosis between Rhizobium galegae and its host plant Galega is an interesting case where the plant species G. orientalis and G. officinalis form effective, nitrogen-fixing, symbioses only with the appropriate rhizobial counterpart, R. galegae bv. orientalis and R. galegae bv. officinalis, respectively. The symbiotic properties of nitrogen-fixing rhizobia are well studied, but more information is needed on the properties of the host plants. The Caucasus region in Eurasia has been identified as the gene centre (centre of origin) of G. orientalis, although both G. orientalis and G. officinalis can be found in this region. In this study, the diversity of these two Galega species in Caucasus was investigated to test the hypothesis that in this region G. orientalis is more diverse than G. officinalis. The amplified fragment length polymorphism fingerprinting performed here showed that the populations of G. orientalis and R. galegae bv. orientalis are more diverse than those of G. officinalis and R. galegae bv. officinalis, respectively. These results support the centre of origin status of Caucasus for G. orientalis at a genetic level. Analysis of the symbiosis-related plant genes NORK and Nfr5 reveals remarkable diversity within the Nfr5 sequence, although no evidence of adaptive evolution could be found.


Assuntos
Galega/genética , Variação Genética , Genoma de Planta , Filogenia , Simbiose/genética , Sequência de Aminoácidos , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , DNA de Plantas/genética , Galega/microbiologia , Dados de Sequência Molecular , Rhizobium/fisiologia , Federação Russa , Análise de Sequência de DNA
3.
Waste Manag ; 119: 11-21, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33032154

RESUMO

This study investigated the possibility to use thermophilic anaerobic high solid digestion of dewatered digested sewage sludge (DDS) at a wastewater treatment plant (WWTP) as a measure to increase total methane yield, achieve pasteurization and reduce risk for methane emissions during storage of the digestate. A pilot-scale plug-flow reactor was used to mimic thermophilic post-treatment of DDS from a WWTP in Linköping, Sweden. Process operation was evaluated with respect to biogas process performance, using both chemical and microbiological parameters. Initially, the process showed disturbance, with low methane yields and high volatile fatty acid (VFA) accumulation. However, after initiation of digestate recirculation performance improved and the specific methane production reached 46 mL CH4/g VS. Plug flow conditions were assessed with lithium chloride and the hydraulic retention time (HRT) was determined to be 19-29 days, sufficient to reach successful pasteurization. Degradation rate of raw protein was high and resulted in ammonia-nitrogen levels of up to 2.0 g/L and a 30% lower protein content in the digestate as compared to DDS. Microbial analysis suggested a shift in the methane producing pathway, with dominance of syntrophic acetate oxidation and the candidate methanogen family WSA2 by the end of the experiment. Energy balance calculations based on annual DDS production of 10000 ton/year showed that introduction of high-solid digestion as a post-treatment and pasteurization method would result in a positive energy output of 340 MWh/year. Post-digestion of DDS also decreased residual methane potential (RMP) by>96% compared with fresh DDS.


Assuntos
Reatores Biológicos , Esgotos , Anaerobiose , Digestão , Metano/análise , Pasteurização , Suécia
4.
Biochim Biophys Acta ; 627(2): 157-64, 1980 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-6243213

RESUMO

The present study was performed to evaluate the effects of calcium ionophore A23187 on adenosine 3',5'-monophosphate (cyclic AMP) and testosterone production in rat interstitial cells. Interstitial cells were incubated in Krebs-Ringer solution with varying amounts of luteinizing hormone, pregnenolone, or A23187. Cyclic AMP and testosterone were measured in the incubation medium after 4 h incubation. A23187 (0.01--10 microgram/ml) caused progressive increases of cyclic AMP formation (from 0.18 +/- 0.02 (S.E.) pmol/10(6) cells for the control of 0.42 +/- 0.02 pmol/10(6) cells, P less than 0.025), while testosterone production remained unaltered. When varying amounts of A23187 were added concomitantly with luteinizing hormone (5 IU/l), A23187 inhibited luteinizing hormone-induced steroidogenesis in a dose-dependent manner, but it had no effect on luteinizing hormone-induced cyclic AMP formation. When pregnenolone (10(-6) M) was added to the cells, testosterone formation increased from 1.50 +/- 0.22 to 8.46 +/- 1.65 ng/10(6) cells. A23187 (1 microgram/ml) had no discernable effect on the conversion of pregnenolone to testosterone. The main effect of increased cytosol calcium on steroidogenesis seems to be at the steps beyond adenylate cyclase-cyclic AMP. These results suggest that calcium is important for the conversion of cholesterol to pregnenolone, while the steps beyond pregnenolone are relatively independent of Ca2+.


Assuntos
Antibacterianos/farmacologia , Calcimicina/farmacologia , AMP Cíclico/biossíntese , Células Intersticiais do Testículo/metabolismo , Testosterona/biossíntese , Animais , Cálcio/farmacologia , Células Intersticiais do Testículo/efeitos dos fármacos , Hormônio Luteinizante/antagonistas & inibidores , Hormônio Luteinizante/farmacologia , Masculino , Pregnenolona/metabolismo , Ratos
5.
Biochim Biophys Acta ; 633(2): 228-36, 1980 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-6257309

RESUMO

The present study examined the effects of cytochalasin B on various steps in the luteinizing hormone (LH)-stimulated increase in testosterone synthesis by collagenase-dispersed interstitial cells of adult rat testis. Cytochalasin B at a concentration range of 0.1--50 microM inhibited the LH-stimulated increase in testosterone synthesis in a dose-dependent manner. Both intracellular and medium (released) testosterone levels were reduced, thus indicating that the decrease was not due to the accumulation of testosterone inside the cell as a result of cytochalasin B treatment. Cytochalasin B also inhibited the 8-bromocyclic AMP and pregnenolone-stimulated testosterone synthesis in a similar dose-dependent manner. Cytochalasin B at the two higher doses (10 and 50 microM) also inhibited the LH-stimulated generation of cyclic AMP by interstitial cells. However, this drug had no effect on basal testosterone synthesis except at the highest concentration added. Previous studies on adrenocorticotropic hormone (ACTH)- and LH-stimulated increase in glucocorticoid and testosterone synthesis in adrenal and Leydig cells, respectively, demonstrated that cytochalasin B or anti-actin inhibited the transport of cholesterol into mitochondria. The present studies suggest that cytochalasin B inhibits at least two additional steps in the LH-stimulated increase in testosterone synthesis: (1) the generation of cyclic AMP at the level of the plasma membrane, and (2) the conversion of pregnenolone to testosterone at the level of the smooth endoplasmic reticulum. It remains to be established whether these are direct effects of cytochalasin B, or whether they are mediated by disruption of microfilaments by cytochalasin B.


Assuntos
Citocalasina B/farmacologia , Células Intersticiais do Testículo/metabolismo , Testosterona/biossíntese , 8-Bromo Monofosfato de Adenosina Cíclica , Animais , AMP Cíclico/análogos & derivados , AMP Cíclico/metabolismo , AMP Cíclico/farmacologia , Relação Dose-Resposta a Droga , Células Intersticiais do Testículo/efeitos dos fármacos , Hormônio Luteinizante/farmacologia , Masculino , Pregnenolona/farmacologia , Ratos
6.
Genetics ; 83(1): 63-5, 1976 May.
Artigo em Inglês | MEDLINE | ID: mdl-17248709

RESUMO

Exposure of freshly shed maize pollen to allyl alcohol vapors allows selective fertilization by mutant alcohol-dehydrogenase-negative grains. Wild-type pollen grains are killed by the enzymatic conversion of allyl alcohol to the highly toxic acrylaldehyde.

7.
Genetics ; 99(2): 267-73, 1981 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17249117

RESUMO

A Ds-suppressed Adh mutant was isolated by the allyl alcohol pollen selection technique. The mutant produces a reduced level of an altered thermolabile enzyme suggesting that the Ds element is inserted in the Adh structural gene. The mutant protein is enzymatically active and does not differ detectably in size from the progenitor protein. A number of possible explanations for the data are presented.

8.
Genetics ; 146(3): 1131-41, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9215914

RESUMO

This article reports the cloning of the genes encoding the Arabidopsis and rice class III ADH enzymes, members of the alcohol dehydrogenase or medium chain reductase/dehydrogenase superfamily of proteins with glutathione-dependent formaldehyde dehydrogenase activity (GSH-FDH). Both genes contain eight introns in exactly the same positions, and these positions are conserved in plant ethanol-active Adh genes (class P). These data provide further evidence that plant class P genes have evolved from class III genes by gene duplication and acquisition of new substrate specificities. The position of introns and similarities in the nucleic acid and amino acid sequences of the different classes of ADH enzymes in plants and humans suggest that plant and animal class III enzymes diverged before they duplicated to give rise to plant and animal ethanol-active ADH enzymes. Plant class P ADH enzymes have gained substrate specificities and evolved promoters with different expression properties, in keeping with their metabolic function as part of the alcohol fermentation pathway.


Assuntos
Aldeído Oxirredutases/genética , Arabidopsis/enzimologia , Oryza/enzimologia , Álcool Desidrogenase/genética , Aldeído Oxirredutases/metabolismo , Aldeído Oxirredutases/fisiologia , Sequência de Aminoácidos , Animais , Arabidopsis/genética , Sequência de Bases , Clonagem Molecular , DNA de Plantas , Evolução Molecular , Humanos , Íntrons , Dados de Sequência Molecular , Oryza/genética , Filogenia
9.
Arch Intern Med ; 141(11): 1505-7, 1981 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7283562

RESUMO

A patient who had severe orthostatic hypotension secondary to ingesting Vacor, a rodenticide containing N-3 pyridilmethyl-N'-nitrophenyl urea (PNU), fully recovered from this initially disabling condition 11 months after poisoning. Initial treatments with elastic stockings, fludrocortisone acetate, and dihydroergotamine mesylate resulted in no obvious improvement of his orthostasis. Findings from a hemodynamic study performed with the patient was severely orthostatic suggested functional impairment of vascular adrenergic nerve terminals as a major lesion. A similar study after recovery from orthostasis showed that the baroreceptor reflex mechanism returned to normal. This report shows that initially severe and disabling orthostatic hypotension may not be a hopelessly permanent sequela of PNU intoxication and that a gradual, spontaneous full recovery from orthostasis is possible.


Assuntos
Hipotensão Ortostática/induzido quimicamente , Compostos de Fenilureia/intoxicação , Rodenticidas/intoxicação , Adulto , Pressão Sanguínea , Vestuário , Di-Hidroergotamina/uso terapêutico , Frequência Cardíaca , Humanos , Hipotensão Ortostática/terapia , Masculino , Tentativa de Suicídio
10.
Arch Intern Med ; 146(9): 1731-5, 1986 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-3753113

RESUMO

A 28-year-old man with the chronic syndrome of Inappropriate antidiuretic hormone secretion and hypertension was found to have an olfactory neuroblastoma. We demonstrated evidence of elevated circulating arginine vasopressin levels, significantly elevated arginine vasopressin and vasopressin neurophysin levels in the tumor extract, and immunohistochemical staining for arginine vasopressin and vasopressin neurophysin in the tumor cells. The patient's clinical syndrome, including hypertension, resolved following subtotal removal of the tumor and radiation therapy. This study identified olfactory neuroblastoma as a definite cause of ectopic arginine vasopressin secretion causing the syndrome of inappropriate antidiuretic hormone secretion.


Assuntos
Arginina Vasopressina/metabolismo , Hipertensão/etiologia , Síndrome de Secreção Inadequada de HAD/etiologia , Tumores Neuroectodérmicos Primitivos Periféricos/complicações , Neoplasias Nasais/complicações , Adulto , Humanos , Masculino , Tumores Neuroectodérmicos Primitivos Periféricos/metabolismo , Tumores Neuroectodérmicos Primitivos Periféricos/patologia , Neurofisinas/metabolismo , Neoplasias Nasais/metabolismo , Neoplasias Nasais/patologia , Mucosa Olfatória/patologia , Células de Schwann/patologia
11.
Endocrinology ; 101(4): 1335-8, 1977 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-561691

RESUMO

Under defined conditions in vitro FSH and LH caused a dose-dependent stimulation of ornithine decarboxylase (ODC) activity in granulosa cells isolated from porcine ovarian follicles. In cells from small follicles, FSH was at least twice as potent an inducer of the enzyme activity as LH. The cells from medium-sized follicles were more responsive to both hormones than cells from small follicles. In addition, the cells from medium-sized follicles were approximately equally responsive to maximal FSH and LH stimulation. Incubation of cells from either small follicles or medium-sized follicles with maximum effective doses of LH plus FSH caused no additive effects.


Assuntos
Carboxiliases/metabolismo , Hormônio Foliculoestimulante/farmacologia , Células da Granulosa/enzimologia , Hormônio Luteinizante/farmacologia , Ornitina Descarboxilase/metabolismo , Animais , Relação Dose-Resposta a Droga , Feminino , Técnicas In Vitro , Suínos
12.
Endocrinology ; 103(5): 1718-24, 1978 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-85547

RESUMO

The role of cAMP as a mediator of gonadotropin stimulation of ovarian ornithine decarboxylase (ODC) activity was studied in granulosa cells isolated from small (1--2 mm) porcine ovarian follicles. These cells responded to both FSH and LH with significant increases in intracellular concentration of cAMP. At concentrations of gonadotropins which were saturating for the induction of ODC activity, FSH was a more potent stimulator of both cAMP production and ODC activity than LH. N,O'-Dibutyryl cAMP (1.0--10.0 mM) caused a dose-dependent stimulation of ODC activity which equaled the maximal effect of LH but was significantly less effective than the saturating dose of FSH. 8-Bromo-cAMP was more potent than N,O'-dibutyryl cAMP and as effective as FSH as an inducer of ODC activity. Addition of theophylline, a phosphodiesterase inhibitor, to the incubation medium resulted in a dose-dependent inhibition of ODC activity in both control and gonadotropin-stimulated cells. In contrast, 1-methyl,3-isobutyl xanthine, another phosphodiesterase inhibitor, potentiated effects of both submaximal and maximal effective doses of gonadotropins while producing no effect on basal ODC activity of these cells. The results of this study are consistent with the concept that cAMP can mediate gonadotropin stimulation of ODC in porcine granulosa cells. In addition, this study shows the importance of proper selection of cAMP analogs and phosphodiesterase inhibitors, and their concentration in studying such effects.


Assuntos
Carboxiliases/metabolismo , AMP Cíclico/fisiologia , Hormônio Foliculoestimulante/farmacologia , Hormônio Luteinizante/farmacologia , Ornitina Descarboxilase/metabolismo , Ovário/enzimologia , 1-Metil-3-Isobutilxantina/farmacologia , Animais , AMP Cíclico/análogos & derivados , AMP Cíclico/farmacologia , Feminino , Células da Granulosa/metabolismo , Inibidores de Fosfodiesterase/farmacologia , Suínos
13.
Endocrinology ; 111(4): 1391-3, 1982 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-6288360

RESUMO

Using a 0-32% continuous metrizamide density gradient, interstitial cells could be separated into five distinct bands. Cells localized in bands 1 (B1), 2 (B2), and 3 (B3) were isolated and incubated for 1h with or without human chorionic gonadotropin (hCG). Both B2 and B3 cells responded to hCG with increased cyclic AMP formation, but only B3 cells produced significantly more testosterone. Protein kinase activity of B2 cells was found to be extremely low compared with B1 and B3 cells. Additional treatment of B3 cells with collagenase did not cause any change in protein kinase activity. These results indicate that decreased protein kinase activity may be responsible for impaired testosterone synthesis in B2 cells.


Assuntos
Células Intersticiais do Testículo/enzimologia , Proteínas Quinases/metabolismo , Testosterona/biossíntese , Animais , Separação Celular , Centrifugação com Gradiente de Concentração , Gonadotropina Coriônica/farmacologia , AMP Cíclico/metabolismo , Células Intersticiais do Testículo/efeitos dos fármacos , Masculino , Ratos , Ratos Endogâmicos
14.
J Clin Endocrinol Metab ; 48(5): 816-20, 1979 May.
Artigo em Inglês | MEDLINE | ID: mdl-429526

RESUMO

The metabolism of the synthetic progestin, [3H]medroxyprogesterone acetate (MPA), was studied in women using a single injection technique. Computer-implemented analysis was used to calculate the MCR (MCRMPA) and volume of distribution (VoMPA) from the steroid disappearance curve. The value of an objective curve-fitting technique was demonstrated. The effect of protocol design (number and frequency of samples) on these metabolic parameters was evaluated. The estimation of VoMPA was most sensitive to alterations of experimental design and biological variability, while MCR was less easily effected. The MCRMPA of 1668 +/- 146 (SEM) liters/day was lower than that for progesterone but higher than that of another synthetic steroid, dexamethasone. Treatment of women with MPA or aminoglutethimide, two drugs known to increase the rates of testosterone and dexamethasone metabolism, respectively, did not alter MCRMPA. From these observations we conclude 1) with the single injection technique it is difficult to estimate Vo of compounds such as MPA which are rapidly metabolized and 2) the MCRMPA was higher than expected and less susceptible to drug-induced changes than the clearance of other steroids.


Assuntos
Medroxiprogesterona/análogos & derivados , Aminoglutetimida/uso terapêutico , Coleta de Amostras Sanguíneas , Neoplasias da Mama/sangue , Feminino , Hirsutismo/sangue , Humanos , Medroxiprogesterona/sangue , Medroxiprogesterona/uso terapêutico , Taxa de Depuração Metabólica , Obesidade/sangue , Oligomenorreia/sangue , Projetos de Pesquisa , Fatores de Tempo
15.
Gene ; 211(2): 187-94, 1998 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-9602122

RESUMO

Rabbit eIF2C (94kDa) has been shown to play important roles in the eukaryotic peptide chain initiation process. In this study, the primary structure of rabbit eIF2C is determined by cDNA cloning. Based on the partial amino acid sequences of Endolys C cleaved fragments, degenerate oligonucleotides were synthesized and used as primers for the polymerase chain reaction to amplify the corresponding cDNA fragment from a rabbit liver cDNA library. This fragment was subsequently used to screen for larger cDNAs. Marathon cDNA amplification and 5'-rapid amplification of cDNA ends were used to confirm the translation start site. Sequences from the overlapping clones were assembled into a 3599-bp composite sequence, which contains a single open reading frame that translates into a 813-deduced amino acid sequence. Northern blot analysis of rabbit liver ploy(A)+ RNA yielded a single message species at approximately 4.6kb. Western blot analysis of rabbit reticulocyte lysate using polyclonal antibody against the 94kDa eIF2C detected a higher-molecular-weight polypeptide (140kDa). No 94kDa polypeptide was detected. The cloned cDNA was further characterized by in-vitro transcription-coupled translation in reticulocyte lysate. The translated product was precipitated with antibodies against eIF2C. Genomic Southern blot analysis indicates that the rabbit eIF2C is a single copy gene. Sequence analysis reveals that rabbit eIF2C has strong homology with a hypothetical protein in Caenorhabditis elegans.


Assuntos
Fatores de Iniciação de Peptídeos/genética , Proteínas/química , Proteínas/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Northern Blotting , Southern Blotting , Sistema Livre de Células , Clonagem Molecular , DNA/análise , DNA/genética , DNA Complementar/análise , DNA Complementar/química , DNA Complementar/genética , Genes/genética , Genoma , Fatores de Troca do Nucleotídeo Guanina , Dados de Sequência Molecular , Peso Molecular , Fatores de Iniciação de Peptídeos/análise , Fatores de Iniciação de Peptídeos/química , Biossíntese de Proteínas/genética , RNA Mensageiro/análise , Coelhos , Análise de Sequência de DNA
16.
Int J Epidemiol ; 20(1): 138-43, 1991 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2066212

RESUMO

Standardized French and English versions of the American Thoracic Society (ATS) respiratory disease questionnaire were administered to 204 English-speaking and 406 French-speaking male blue-collar aviation workers unexposed to occupational respiratory hazards. After adjusting for smoking status, age, years of education, foreign birth and maternal language other than French or English, no significant differences between the two questionnaires were found for response rates to usual cough, usual phlegm, mild or moderate dyspnoea, and chronic bronchitis. French-speaking workers reported significantly less wheeze with colds (OR = 0.60, p less than 0.02) and wheeze apart from colds (OR = 0.55, p less than 0.05) than the English-speaking group, but, the occurrence of wheeze on most days or nights was similar for both groups (OR = 1.02, NS). For 66 bilingual workers who completed both French and English questionnaires at a time interval of approximately two months, highly consistent results were found for sociodemographic data, smoking habits, cough, phlegm, breathlessness and chronic bronchitis, but not for wheeze with or apart from colds (agreement less than 90%; Kappa less than 0.50). These results reflect the difficulties in translating the concept of 'wheeze' from English to French. We conclude that most symptoms elicited by the French questionnaire may be generalized to English-speaking populations, but that questions pertaining to wheeze on most days or nights may be preferable to other questions concerning wheeze.


Assuntos
Idioma , Doenças Profissionais/epidemiologia , Doenças Respiratórias/epidemiologia , Inquéritos e Questionários , Coleta de Dados/métodos , Feminino , Humanos , Masculino , Pneumologia , Quebeque , Sons Respiratórios , Sociedades Médicas , Estados Unidos
17.
Metabolism ; 30(2): 156-9, 1981 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-6258009

RESUMO

The effects of tamoxifen on rat testicular steroidogenesis were studied using dispersed interstitial cells. Tamoxifen significantly inhibited LH-, and 8-bromo-adenosine 3',5'-monophosphate (8-bromo-cyclic AMP)-stimulated testosterone synthesis in a dose-dependent manner. Tamoxifen (10(-5)M) also reduced LH-stimulated cyclic AMP formation. The addition of equimolar concentrations of 17 beta-estradiol or tamoxifen separately to interstitial cells resulted in similar inhibition of LH-stimulated testosterone synthesis. When equimolar concentrations of 17 beta-estradiol and tamoxifen were added concomitantly to interstitial cells, the inhibition was additive. Present studies demonstrate that tamoxifen has direct inhibitory effects on testicular steroidogenesis: both at the plasma membrane resulting in decreased cyclic AMP formation and also at steps subsequent to cyclic AMP.


Assuntos
Células Intersticiais do Testículo/efeitos dos fármacos , Tamoxifeno/farmacologia , Animais , Células Cultivadas , AMP Cíclico/sangue , Relação Dose-Resposta a Droga , Hormônio Luteinizante/farmacologia , Masculino , Ratos , Testosterona/sangue
18.
Surv Ophthalmol ; 43(3): 233-44, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9862311

RESUMO

Understanding the effect of serum lipid levels on risk factors for coronary heart disease and how they are influenced by medical therapy may lead to overall better care of the glaucoma patient. Elevated low-density lipoprotein and total cholesterol levels are major risk factors for heart disease. In contrast, high-density lipoprotein (HDL) is protective for heart disease. beta-adrenergic blockers, a class of medicines used to treat glaucoma, may influence serum lipid levels. Oral nonselective beta-adrenergic blockers reduce HDL cholesterol by 19% and increase triglycerides by 20-40%. Furthermore, topical nonselective beta-adrenergic blockers also decrease serum HDL and worsen the total cholesterol/HDL ratio. However, beta-blockers with intrinsic sympathomimetic activity appear to be lipid neutral. At present, there is no clear clinical evidence to indicate that changes in serum lipids with use of topical beta-adrenergic blockers significantly affect the clinical course of the patient. Little information is available for other classes of medicines used topically to treat glaucoma. However, oral preparations of prostaglandins, alpha-adrenergic agonists, angiotensin-converting enzyme inhibitors, and calcium channel blockers do not adversely affect serum lipid levels. Further study is required on newer glaucoma preparations to determine their specific actions on lipid levels. Additionally, further work is required to understand the significance of not only the adverse effect of beta-adrenergic blockers on lipid levels, but their overall effect on long-term cardiac morbidity and mortality.


Assuntos
Glaucoma de Ângulo Aberto/tratamento farmacológico , Lipídeos/sangue , Antagonistas Adrenérgicos beta/efeitos adversos , Antagonistas Adrenérgicos beta/uso terapêutico , Doença das Coronárias/sangue , Doença das Coronárias/induzido quimicamente , Glaucoma de Ângulo Aberto/sangue , Humanos , Hiperlipidemias/sangue , Hiperlipidemias/induzido quimicamente , Fatores de Risco
19.
Am J Trop Med Hyg ; 34(6): 1173-8, 1985 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2422967

RESUMO

Hybridoma antibodies (Hab) were prepared against the Karp, Gilliam and Kato strains of Rickettsia tsutsugamushi and were examined for homologous and heterologous reactivity using an indirect immunofluorescence assay. Strain-specific Hab demonstrated homologous IFA titers ranging from 1/320 to 1/1,280 and did not react (less than 1/10) with the heterologous strains. The cross-reactive Hab generally reacted equally with all three strains in the scrub typhus group; however, there were some Hab that reacted with only one of the two heterologous strains tested. The Hab also were examined in enzyme-linked immunosorbent assays with scrub typhus antigens eluted from SDS-polyacrylamide gels. Most Hab reacted with either one or several of the six eluted antigens detected with a polyclonal immune serum. It was also observed that strain-specific and cross-reactive Hab sometimes reacted with the same antigen, suggesting the existence of multiple antigenic determinants in one electrophoretic peak. The data suggest that strain-specific Hab can be used in the indirect immunofluorescence assay to identify isolates of R. tsutsugamushi without the cross-reactions usually observed with polyclonal antisera, and that they are useful probes for detection and analysis of rickettsial antigens.


Assuntos
Anticorpos Monoclonais/imunologia , Antígenos de Bactérias/imunologia , Orientia tsutsugamushi/imunologia , Anticorpos Antibacterianos/imunologia , Reações Cruzadas , Epitopos , Especificidade da Espécie
20.
Fertil Steril ; 46(2): 300-7, 1986 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-3525237

RESUMO

There have not been studies assessing the effects of chronic testosterone cypionate (TC) therapy on circulating levels of testosterone (T), estradiol (E2), free T, bioavailable T (BAT), luteinizing hormone (LH), and sexual function in impotent men with low T levels. This study was a double-blind crossover using 200 mg of TC or placebo given intramuscularly every 14 days for six injections and the other medication given for six doses. Blood was drawn before each injection. Mean concentrations of T, E2, free T, and BAT were the same on TC or on placebo, but serum LH was significantly suppressed during intramuscular TC. With TC statistically significant improvements in libido and in potency were noted. Five of the men were able to have vaginal sex while taking TC. TC injections every 14 days do not appear to maintain increased T concentrations for 2 full weeks, and other dosage/injection schedules are being evaluated, but there were improvements in libido and potency.


Assuntos
Disfunção Erétil/tratamento farmacológico , Testosterona/análogos & derivados , Idoso , Ensaios Clínicos como Assunto , Método Duplo-Cego , Estradiol/sangue , Humanos , Hormônio Luteinizante/sangue , Masculino , Pessoa de Meia-Idade , Radioimunoensaio , Distribuição Aleatória , Testosterona/sangue , Testosterona/uso terapêutico
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