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1.
Environ Monit Assess ; 193(8): 491, 2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34259956

RESUMO

Coral reefs are fragile and endangered ecosystems in the tropical marine and coastal environment. Thermal stress due to marine heat waves (MHW) could cause significantly negative impacts on the health conditions, i.e., bleaching of the coral ecosystem. The current study is an attempt to quantify the intensity of coral bleaching in the Andaman region in recent decades using the intensity of marine heat wave (IMHW) estimated from satellite measured sea surface temperature (SST). A linear regression model was developed between IMHW and in situ observations of percent coral bleaching (PCB) which has the slope 7.767 (of IMHW unit) and intercept (- 141.7). Further, an attempt was also made to establish the relationship between PCB and the ratio between the remote sensing reflectance (Rrs) at 443 and 531 nm to upscale the percentage of coral bleaching at synoptic scales. A significant positive correlation between the PCB and band ratio index was found (R2 = 0.72). This approach can be used for the operational monitoring of coral reef beaching in this region.


Assuntos
Antozoários , Recifes de Corais , Animais , Ecossistema , Monitoramento Ambiental , Temperatura Alta
2.
PLoS One ; 16(10): e0258166, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34606515

RESUMO

Understanding the spatial spreading patterns of plant-available sulphur (S) (AS) and plant-available micronutrients (available zinc (AZn), available iron (AFe), available copper (ACu), available manganese (AMn) and available boron (AB)) in soils, especially in coastal agricultural soils subjected to various natural and anthropogenic activities, is vital for sustainable crop production by adopting site-specific nutrient management (SSNM) strategies. We studied the spatial distribution patterns of AS, AZn, AFe, ACu, AMn, and AB in cultivated soils of coastal districts of India using geostatistical approaches. Altogether 39,097 soil samples from surface (0 to 15 cm depth) layers were gathered from farm lands of 68 coastal districts. The analysis of soil samples was carried out for soil pH, electrical conductivity (EC), soil organic carbon (SOC) and AS, AZn, AFe, ACu, AMn, and AB. Soil pH, EC and SOC varied from 3.70 to 9.90, 0.01 to 7.45 dS m-1 and 0.02 to 3.74%, respectively. The concentrations of AS, AZn, AFe, ACu, AMn, and AB varied widely in the study area with their corresponding mean values were 37.4±29.4, 1.50±1.53, 27.9±35.1, 2.14±1.74, 16.9±18.4 and 1.34±1.52 mg kg-1, respectively. The coefficient of variation values of analyzed soil parameters varied from 14.6 to 126%. The concentrations of AS, AZn, AFe, ACu, AMn, and AB were negatively and significantly correlated with soil pH and positively and significantly correlated with SOC. The geostatistical analysis indicated stable, Gaussian and exponential best-fit semivariogram models with moderate to strong spatial dependence for available nutrients. The generated spatial spreading maps revealed different distribution patterns for AS, AZn, AFe, ACu, AMn, and AB. There were variations in spatial spreading patterns of AS, AZn, AFe, ACu, AMn, and AB in east- and west-coastal area. About 62, 35, 12, 0.4, 23 and 45% of the study area had deficiency of AS, AZn, AFe, ACu, AMn, and AB, respectively. The spatial spreading maps will be highly useful for SSNM in the cultivated coastal soils of the country. This study could also be used as a base for assessing spatial spreading patterns of soil parameters in cultivated coastal areas of other parts of the world.


Assuntos
Micronutrientes/análise , Solo/química , Enxofre/análise , Agricultura , Geografia , Índia , Estatística como Assunto
3.
Clin Pharmacol Ther ; 27(3): 395-401, 1980 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7357796

RESUMO

Kinetics of zomepirac, an oral, nonnarcotic analgesic, were studied in healthy males in 3 clinical experiments. In study A, zomepirac 100 mg was taken as tablet, capsule, and solution. Bioavailability of zomepirac from the 3 dosage forms was much the same. Zomepirac absorption was rapid, peak plasma concentrations being reached within 1 to 1 hr. Plasma concentration profile could be described by the 2-compartmentoral absorption model with an absorption rate constant (Ka) of 7.66 hr-1 t 1/2 = 0.09 hr), a rapid disposition rate constant (alpha) of 0.75 hr-1 (t 1/2 = 0.94 hr), and a slow disposition rate constant (beta) of 0.16 hr-1 (t 1/2 = 4.3 hr). In study B, safety and acceptability were established with 100 mg 4 times a day for 14 days followed by 150 mg 4 times a day for 14 days. Zomepirac plasma levels indicated attainment of steady state within less than 3 days of treatment. There was little drug accumulation on the regimens studied. There was no change in plasma kinetics after 14 days on either regimen. In study C, dose/bioavailability response was followed at 50-, 100-, and 200-mg dose levels. There were linear correlations between dose and peak plasma concentration, area under the plasma concentration-time curve, and urinary excretion of intact and total (intact + glucuronide conjugate) zomepirac during the 12 hr following drug administration.


Assuntos
Analgésicos/metabolismo , Pirróis/metabolismo , Tolmetino/metabolismo , Adulto , Analgésicos/sangue , Analgésicos/urina , Relação Dose-Resposta a Droga , Humanos , Absorção Intestinal , Rim/metabolismo , Cinética , Masculino , Taxa de Depuração Metabólica , Tolmetino/análogos & derivados , Tolmetino/sangue , Tolmetino/urina
4.
Clin Pharmacol Ther ; 32(3): 371-7, 1982 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7105628

RESUMO

Tolmetin kinetics were determined in the plasma and synovial fluid of five rheumatoid arthritis patients after they had ingested tolmetin (400 mg every 6 hr) for 7 days. Tolmetin was rapidly absorbed, with average peak levels in plasma and synovial fluid occurring at 45 min and 2 hr. The drug concentration in synovial fluid was higher than that in plasma for prolonged periods, while the rates of elimination from both plasma and synovial fluid were similar. The average half-lives of tolmetin in plasma and synovial fluid were 6.77 +/- 1.47 hr and 6.90 +/- 2.3 hr. Total prostaglandin E levels in synovial fluid of these patients were suppressed for at least 24 hr after the last dose of tolmetin, suggesting that PGE synthesis continues to be suppressed even by the very low concentrations of tolmetin remaining after 24 hr.


Assuntos
Artrite Reumatoide/metabolismo , Prostaglandinas E/análise , Pirróis/metabolismo , Líquido Sinovial/análise , Tolmetino/metabolismo , Adulto , Artrite Reumatoide/tratamento farmacológico , Feminino , Meia-Vida , Humanos , Cinética , Masculino , Pessoa de Meia-Idade , Líquido Sinovial/efeitos dos fármacos , Tolmetino/análise , Tolmetino/uso terapêutico
5.
J Clin Pharmacol ; 32(12): 1089-95, 1992 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1487546

RESUMO

The effects of meals and meal composition on the bioavailability of fenretinide, N-(4-hydroxyphenyl) retinamide, a synthetic retinoid undergoing clinical trials, were examined in two separate studies using an open, randomized, crossover design. In the first study, 13 healthy male volunteers received 300-mg doses of fenretinide (1) while fasting and (2) after a high-fat breakfast. In a subsequent study, 15 subjects received 300 mg fenretinide after each of three different test meals (high-fat, high-protein, and high-carbohydrate) separated by a 1-week washout period. Plasma specimens obtained over a 72-hour period after each treatment were assayed by high-pressure liquid chromatography to characterize the effects of a meal and meal composition on the bioavailability of fenretinide. Results from the initial study demonstrated a significant increase in the bioavailability of fenretinide after a high-fat meal. In the follow-up study, the bioavailability of fenretinide, as assessed by total area under the plasma concentration curve, was three times greater after the high-fat meal than after the high-carbohydrate meal. This supported the findings of the first study. Although to a lesser extent, the high-protein meal also produced a greater area under the curve than the high-carbohydrate meal. These combined findings demonstrate that the bioavailability of fenretinide is markedly influenced not only by administration with meals but also by the specific composition of such meals.


Assuntos
Ingestão de Alimentos/fisiologia , Fenretinida/farmacocinética , Alimentos , Adulto , Disponibilidade Biológica , Carboidratos da Dieta/administração & dosagem , Gorduras na Dieta/administração & dosagem , Proteínas Alimentares/administração & dosagem , Jejum/metabolismo , Fenretinida/sangue , Humanos , Masculino , Pessoa de Meia-Idade
6.
J Clin Pharmacol ; 36(11): 1072-7, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8973996

RESUMO

Some fluoroquinolone drug-drug interactions involving inhibition of the hepatic metabolism of agents such as theophylline and caffeine have been identified. This study was designed to investigate the potential interaction of the fluoroquinolone levofloxacin in a standard multiple-dose regimen with the oral anticoagulant warfarin. Sixteen healthy male volunteers were given a single oral dose of 30 mg warfarin sodium during a multiple-dose regimen of placebo or levofloxacin 500 mg twice daily, in a placebo-controlled, randomized, double-blind, two-way crossover design. Plasma R(+) and S(-) warfarin concentrations and prothrombin times were measured for 6 days after administration of each warfarin dose. The pharmacokinetic parameters of both enantiomers of warfarin were comparable in the absence and presence of levofloxacin, with no significant differences noted in warfarin peak plasma concentration, time to peak plasma concentration, apparent total body clearance, and terminal disposition half-life. Levofloxacin also had no significant effect on warfarin pharmacodynamics, as assessed by baseline-corrected maximum prothrombin time, time to maximum prothrombin time, and area under the prothrombin time-versus-time curve. The lack of pharmacokinetic or pharmacodynamic interaction observed in this study suggests that a clinically important effect of levofloxacin on warfarin is unlikely to occur during concurrent therapy.


Assuntos
Anti-Infecciosos/farmacologia , Anticoagulantes/farmacocinética , Levofloxacino , Ofloxacino/farmacologia , Varfarina/farmacocinética , Administração Oral , Adulto , Anti-Infecciosos/farmacocinética , Anticoagulantes/farmacologia , Coagulação Sanguínea/efeitos dos fármacos , Estudos Cross-Over , Método Duplo-Cego , Esquema de Medicação , Interações Medicamentosas , Humanos , Fígado/metabolismo , Masculino , Varfarina/farmacologia
7.
J Clin Pharmacol ; 27(2): 144-50, 1987 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3680566

RESUMO

In a four-segment long-term (greater than or equal to 6 mo) study, patients with schizophrenia received oral haloperidol in single daily doses and subsequently depot intramuscular (IM) haloperidol decanoate q28d. For each route of administration, a period of stabilization was followed by a maintenance period. Dosages for both oral haloperidol and IM haloperidol decanoate were determined on the basis of the patient's past psychiatric history and clinical response during the stabilization period. To characterize the concentration-time profile of the two routes of administration, blood samples were obtained on two separate occasions at steady state during maintenance dosing for each route of administration. Examination of values for cumulative area under the plasma concentration-time curves (AUC) to each sampling time indicated a sustained release of haloperidol from the intramuscularly administered haloperidol decanoate. Dose ranges during maintenance periods were 5-35 mg/d for oral haloperidol (mean, 17 mg/d), and 75-500 mg/28 d for IM haloperidol decanoate (mean, haloperidol decanoate was 243 mg equivalents of haloperidol/28 d). The ratio of long-acting to daily oral doses during maintenance therapy ranged from 9.4:1.0 to 15.0:1.0 (mean, 14.1:1.0). At these ratios, plasma concentration data showed that haloperidol decanoate gave lower values than did oral haloperidol for peak plasma, minimum plasma, and mean steady-state plasma concentrations. The absolute concentration swing was significantly less for decanoate than for the oral drug. Dose-normalized AUC values were compared determine the IM dose of haloperidol decanoate that would have yielded haloperidol plasma concentrations equivalent to those resulting from daily oral administration of haloperidol for 28 days.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Haloperidol/farmacocinética , Esquizofrenia/metabolismo , Adulto , Idoso , Disponibilidade Biológica , Cromatografia Líquida de Alta Pressão , Haloperidol/administração & dosagem , Humanos , Injeções Intramusculares , Pessoa de Meia-Idade , Esquizofrenia/tratamento farmacológico
8.
J Clin Pharmacol ; 24(8-9): 371-80, 1984.
Artigo em Inglês | MEDLINE | ID: mdl-6480878

RESUMO

The pharmacokinetic interaction between zomepirac and aspirin was studied in 12 healthy males who received a single dose of 100 mg zomepirac sodium on days 1 and 5 and 975 mg aspirin every 6 hours on days 2 to 5. The results indicated that in the presence of salicylate, the peak concentration of zomepirac was depressed; peak time, AUC(0-24 hr), and clearance of total drug remained unchanged. Percentage unbound zomepirac was increased twofold. In the presence of zomepirac, the peak concentration and AUC of salicylate were increased and clearance decreased. The data suggest that zomepirac and salicylate compete with each other for the enzymes and/or cofactors involved in glucuronidation. This competition for metabolic clearance offsets the consequences of the zomepirac-salicylate interactions at the plasma protein binding sites. However, in light of increased unbound zomepirac as well as decreased clearance of unbound drug, concomitant therapy of zomepirac and aspirin is not advised.


Assuntos
Aspirina/farmacologia , Pirróis/farmacologia , Tolmetino/farmacologia , Adulto , Aspirina/sangue , Proteínas Sanguíneas/metabolismo , Interações Medicamentosas , Hipuratos/sangue , Humanos , Cinética , Masculino , Ligação Proteica , Salicilatos/sangue , Ácido Salicílico , Tolmetino/análogos & derivados , Tolmetino/sangue
9.
J Clin Pharmacol ; 35(2): 137-41, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7751422

RESUMO

The effects of end-stage renal disease (ESRD) and hemodialysis on the in vitro plasma protein binding of bepridil hydrochloride were investigated. The possible influence of bepridil metabolites on bepridil-protein binding in ESRD patients was also examined. Plasma samples were obtained from six patients with ESRD. Bepridil-plasma protein binding was measured by microequilibrium dialysis after addition of freshly prepared bepridil-14C (239 microCi/mg) at a final concentration of 2 micrograms/mL. The percentage of free bepridil in peripheral venous samples drawn on a nondialysis day was lower (i.e., binding was greater) in the patients with ESRD relative to previous observations in healthy subjects (0.15% +/- 0.04% versus 0.31% +/- 0.05% (mean +/- SD). The plasma concentrations of alpha-1-acid glycoprotein (AAG), the principal bepridil binding protein, were also higher in ESRD patients (110 +/- 32 mg/dL) than previously reported in healthy subjects. Although hemodialysis resulted in significant increases in AAG, total protein, and albumin concentrations, no significant difference in bepridil-plasma protein binding was detected between predialysis and postdialysis peripheral venous samples in the presence (0.16 versus 0.18) or absence (0.20 versus 0.17) of bepridil metabolites. The percentage of free bepridil in plasma from both the arterial and venous limbs of the dialyzer during hemodialysis (means of free bepridil ranged from 0.24-0.28%) was higher than in samples drawn from a peripheral vein. This displacement of bepridil from its binding sites as blood passes through the dialyzer may have been owing to the presence of high local concentrations of plasticizers. Confirmation of this hypothesis will require further investigation.


Assuntos
Bepridil/sangue , Proteínas Sanguíneas/metabolismo , Falência Renal Crônica/sangue , Diálise Renal , Adulto , Creatinina/metabolismo , Feminino , Humanos , Falência Renal Crônica/terapia , Pessoa de Meia-Idade , Orosomucoide/metabolismo , Ligação Proteica , Albumina Sérica/metabolismo
10.
J Clin Pharmacol ; 36(10): 884-91, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8930774

RESUMO

Topiramate, a new antiepileptic drug effective in controlling partial-onset seizures, was administered to humans for the first time as single oral doses of 100 mg, 200 mg, 400 mg, 800 mg, and 1,200 mg in a phase I safety and pharmacokinetic study. Model-independent pharmacokinetic data analysis was performed on plasma concentration and renal excretion data for topiramate. Maximum plasma concentrations (Cmax) were observed between 1.4 and 4.3 hours after administration. Mean values for plasma Cmax and area under the concentration-time curve (AUC) increased linearly with dose; however, a greater-than-proportional increase in both parameters was observed, probably due to saturable binding of the drug to erythrocytes. Mean oral clearance (Cl/F) was 22.5 to 36.1 mL/min and mean volume of distribution (Vd/F) was 38.5 to 58.0 L. Approximately 50% of the dose was excreted renally and cumulative urinary excretion increased linearly and proportionally over the 200 mg to 1,200 mg dose range. Elimination half-life (t1/2) values calculated from plasma (21.5 hrs) and urinary data (18.5 hrs) were consistent and independent of dose. Intersubject variability was low for all parameters. Renal clearance was 13.9 mL/min, suggesting that renal tubular reabsorption may be prominently involved in the renal handling of topiramate. The elimination profile of topiramate indicated that longer sampling times are necessary in future studies to more accurately determine the t1/2. Food effect studies indicated a slight reduction in the rate (approximately 10% decrease in mean Cmax and mean tmax approximately 2 hours later) but not the extent of absorption when topiramate was given with food. Topiramate demonstrates a number of favorable pharmacokinetic features, including linear and predictable dose-concentration relationships, excretion mainly as unchanged drug by the kidney, a dose-independent t1/2, low intersubject variability in pharmacokinetic parameters, and lack of clinically significant effect of food on bioavailability.


Assuntos
Anticonvulsivantes/farmacocinética , Interações Alimento-Droga , Frutose/análogos & derivados , Adolescente , Adulto , Análise de Variância , Anticonvulsivantes/administração & dosagem , Anticonvulsivantes/análise , Disponibilidade Biológica , Cromatografia Gasosa , Método Duplo-Cego , Frutose/administração & dosagem , Frutose/análise , Frutose/farmacocinética , Humanos , Modelos Lineares , Masculino , Taxa de Depuração Metabólica , Topiramato
11.
J Clin Pharmacol ; 38(1): 90-3, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9597565

RESUMO

Certain fluoroquinolones have been shown to elevate the serum concentrations of the immunosuppressant cyclosporine. It is thus important to investigate the potential interaction between levofloxacin, a new fluoroquinolone antimicrobial agent, and the pharmacokinetics of cyclosporine. Twelve healthy subjects (6 men, 6 women) were enrolled in and completed a placebo-controlled, randomized, double-blind, two-phase crossover study. Subjects were given a single oral 10-mg/kg dose of cyclosporine solution during multiple-dose twice-daily oral treatment with placebo or 500 mg of levofloxacin. Blood cyclosporine concentrations were measured for 48 hours after each cyclosporine dose for pharmacokinetic evaluation. Cyclosporine pharmacokinetic parameters were comparable and not significantly different in the absence and presence of levofloxacin. Results of this study suggest that a clinically important pharmacokinetic interaction between levofloxacin and cyclosporine is unlikely to occur during concurrent therapy.


Assuntos
Ciclosporina/farmacocinética , Imunossupressores/farmacocinética , Levofloxacino , Ofloxacino/farmacologia , Adulto , Estudos Cross-Over , Método Duplo-Cego , Interações Medicamentosas , Feminino , Humanos , Masculino
12.
J Clin Pharmacol ; 35(4): 379-83, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7650227

RESUMO

The pharmacokinetics of bepridil and 2 of its major metabolites (McN-A-2600 and McN-6303) were studied in 6 patients with end-stage renal disease (ESRD) before and after hemodialysis. Patients underwent dialysis 1 day after a single oral 200-mg dose of bepridil hydrochloride; blood was sampled for up to 7 days. The mean (+/- SD) peak plasma concentration, time of peak concentration, and area under the plasma concentration-time curve (0-168 hours) for each agent were as follows: bepridil, 806 +/- 321 ng/mL, 2.6 +/- 1.6 hours, 4.87 +/- 1.21 micrograms.h/mL; McN-A-2600, 57 +/- 16 ng/mL, 4.2 +/- 2.0 hours, 0.53 +/- 0.29 microgram.h/mL; McN-6303, 284 +/- 120 ng/mL, 4.7 +/- 1.5 hours, 4.06 +/- 1.11 micrograms.h/mL. The bepridil area under the curve corrected for dose was similar to that in healthy volunteers, suggesting that plasma clearance was unaffected by severe renal impairment. None of the compounds were removed by dialysis, and no rebound in plasma concentrations was observed after the end of dialysis. The disposition of bepridil appears to be unchanged in patients with ESRD; and is unaffected by hemodialysis. Thus, no dosage adjustment will be required for ESRD patients and those receiving hemodialysis with cuprophane filters.


Assuntos
Bepridil/farmacocinética , Falência Renal Crônica/metabolismo , Administração Oral , Adulto , Bepridil/administração & dosagem , Bepridil/análogos & derivados , Bepridil/sangue , Feminino , Humanos , Falência Renal Crônica/terapia , Pessoa de Meia-Idade , Diálise Renal
13.
J Pharm Sci ; 72(9): 991-4, 1983 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-6631711

RESUMO

Twenty-three normal male subjects received 900 mg of acetaminophen and 750 mg of chlorzoxazone as an oral suspension. Analysis of plasma samples indicated a rapid absorption and rapid elimination of chlorzoxazone. Average values of the elimination half-life and plasma clearance were 1.12 +/- 0.48 hr and 148.0 +/- 39.9 ml/min, respectively. Analysis of urine samples showed that chlorzoxazone was eliminated from the body as the glucuronide conjugate of the intermediate metabolite 6-hydroxychlorzoxazone, to the extent of 74% of the dose. The plasma and the urinary excretion data were fitted to theoretical equations, and excellent fits were obtained using a five-parameter pharmacokinetic model.


Assuntos
Benzoxazóis/metabolismo , Clorzoxazona/metabolismo , Acetaminofen/metabolismo , Adulto , Biotransformação , Clorzoxazona/análogos & derivados , Clorzoxazona/urina , Combinação de Medicamentos , Meia-Vida , Humanos , Cinética , Masculino , Modelos Biológicos
14.
Am J Vet Res ; 36(11): 1623-30, 1975 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1238042

RESUMO

Tissue from the infundibulum region of the uterine tube (oviduct) of guinea pigs, cattle, sheep, and swine was examined by electron microscopy. In all specimens, cilia and ciliary rootlets were present in variable numbers in the ciliated cells during both the follicular and the luteal phases of the estrous cycle. True degeneration of cilia was not evident during luteal phase or pregnancy. The ciliary rootlets in ruminant and nonruminant species had structural similarities to those described in people and rhesus monkeys. These organelles measured approximately 1 mum long in most species studied, but in the cow, the rootlets, extending downward into the cytoplasm from the proximal end of the basal body, reached a length of 2 mum. The rootlets had a cross-striation of thick and thin bands, the period measuring 40 to 60 nm. Mitochondria were closely associated with the rootlets. The rootlets usually formed a small angle to the axis of the cilium. These organelles probably function as anchoring or stabilizing structures for the motile cilia. Results indicated that the rootlets are more widely distributed in mammalian uterine tube cilia than previously postulated. Polyribosomes, microfilaments, microtubules, and electron-opaque fibrous granules were frequently seen in the cytoplasm of the ciliated cells. The presence of fibrous granules in close association with the basal bodies indicate that these granules have a role in the development of cilia and rootlets. Cilia and precursor fibrous granules were also seen in porcine fetal uterine tube epithelial cells.


Assuntos
Tubas Uterinas/ultraestrutura , Animais , Bovinos/fisiologia , Cílios/ultraestrutura , Grânulos Citoplasmáticos/ultraestrutura , Células Epiteliais , Epitélio/ultraestrutura , Estro , Tubas Uterinas/fisiologia , Feminino , Cobaias/fisiologia , Gravidez , Ovinos/fisiologia , Suínos/fisiologia
15.
Am J Vet Res ; 38(2): 157-68, 1977 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-139117

RESUMO

Ultrastructural and ultracytochemical features of the uterine tube (oviduct) infundibulum were studied in 8 Hereford cows, which were slaughtered in pairs on days 1 (estrus), 3, 9 or 10, and 18 of the estrous cycle. Fibrous granules (60 to 80 nm), which are supposedly related to basal body replication, were observed in the apical cytoplasm of ciliated cells. Close association between basal bodies and fibrous granules was apparent, especially during the follicular phase. Cilia were observed throughout of estrous cycle, although degeneration of cilia was not observed at any phase of the cycle. Prominent, striated rootlets were observed during both the follicular and luteal phases of the cycle. Maximum secretory cell differentiation was apparent during the follicular phase, at which time these cells were characterized by having a well-developed, rough endoplasmic reticulum with dilated cisternae, numerous ribosomes, and secretory granules of varied size and density. A prominent feature of the secretory granules was their membranous structure, consisting of concentric lamellae of equal dimensions. During the luteal phase, cytoplasmic protrusions were prominent, and extruded nuclei along with other cytoplasmic organelles were present in the tubal lumen. The presence of a well-developed, rough endoplasmic reticulum and numerous secretory granules during the follicular phase indicates that secretory activity of the uterine tube infundibulum may be stimulated by estrogen. During estrus, the cytoplasm of the stromal cells displayed abundant, rough endoplasmic reticulum with dilated cisternae. The increased and extensively dilated rough endoplasmic reticulum at the time of estrus probably indicates increased protein synthesis by the stromal cells. The presence of adenosine triphosphatase activity on the membrane of cilia suggests that this enzyme is involved in energy-forming reactions related to the vigorous action of cilia. The presence of acid phosphatase activity on the cell membrane of the epithelium, microvilli, and secretory granules may indicate involvement in the secretory mechanism of the cell.


Assuntos
Bovinos/anatomia & histologia , Tubas Uterinas/ultraestrutura , Adenosina Trifosfatases/metabolismo , Fosfatase Alcalina/metabolismo , Animais , Bovinos/metabolismo , Cílios/ultraestrutura , Grânulos Citoplasmáticos/ultraestrutura , Retículo Endoplasmático/ultraestrutura , Células Epiteliais , Epitélio/ultraestrutura , Estro , Tubas Uterinas/enzimologia , Feminino , Gravidez
16.
Am J Vet Res ; 36(11): 1631-41, 1975 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1238043

RESUMO

The effect of exogenous contraceptive steroids on the ultrstructural features of the endometrial stromal cells was studied in 64 guinea pigs allotted to 4 treatment groups. Four guinea pigs from each group were killed 14, 28, 56, and 84 days after treatment with mestranol (0.01 mg/day in 1 ml of oil) or with norethindrone (0.2 mg/day in 1 ml of oil) or with a combination of both (0.001 mg of mestranol/day and 0.02 mg of norethindrone/day in 1 ml of oil) or with 1 ml of vegetable oil (oil-treated controls). An additional 12 normal guinea pigs (nontreated controls) were killed during the follicular and luteal phases of the estrous cycle, and uterine specimens were immediately collected to determine base line characteristics. During estrus, the stromal cells of these 12 guinea pigs had abundant dilated rough endoplasmic reticulum. The interstitium was filled with collagen. During the luteal phase. the cytoplasm of the stromal cells of the 12 guinea pigs contained a prominent nucleus and rough endoplasmic reticulum with undilated cisterns. The interstitium contained sparse amounts of collagen. The stromal cells of the oil-treated control guinea pigs seemed similar in ultrastructure to the stromal cells of the 12 nontreated control guinea pigs at the luteal phase. Mestranol-fed guinea pigs had dilated rough endoplasmic reticulum and well-developed Golgi apparatus within 2 weeks of initial treatment. The interstitium of mestranol-treated guinea pigs had more collagen than that of the oil-treated controls and nontreated controls during the luteal phase. Prolonged treatment with mestranol caused extensive dilation of the cisternae of the endoplasmic reticulum. The interstitium was filled with abundant collagen. Pronounced alterations in the cytoplasmic organelles or extracellular connective tissue were not ovserved in guinea pigs given norethindrone alone or norethindrone in combination with mestranol for 14 days. The stromal cells closely resembled the cells of the mature animal at luteal phase. However, the dilated rough endoplasmic reticulum that occurred in cells after mestranol treatment was not seen in stromal cells after 84 days of treatment with norethindrone. Dilation of rough endoplasmic reticulum was also observed when both the contraceptive steroids were given simultaneously for 84 days. The increased and extensively dilated rough endoplasmic reticulum seen during the follicular phase and after mestranol administration or after 84 days of treatment with mestranol and norethindrone probably indicates increased protein synthesis by the endometrial stromal cells.


Assuntos
Endométrio/ultraestrutura , Mestranol/farmacologia , Noretindrona/farmacologia , Animais , Endométrio/efeitos dos fármacos , Retículo Endoplasmático/efeitos dos fármacos , Retículo Endoplasmático/ultraestrutura , Estro , Feminino , Cobaias , Gravidez
17.
Am J Vet Res ; 37(2): 189-97, 1976 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1259215

RESUMO

The time required for occurrence of estrogen-induced uterine tubal (oviductal) ciliogenesis and for differentiation of secretory cells was studied, utilizing electron microscopy procedures. Sixteen cycling gilts were ovariectomized; 3 to 4 months later, 12 principal gilts were each given subcutaneous injections of 17 beta-estradiol in 0.5 ml of corn oil at the rate of 200 mug/day, and 4 control gilts were given injections of corn oil only at the rate of 0.5 ml/day. Two principals each were killed on days 1, 2, 3, 4, 5, and 7 after start of treatment. The epithelial heights were low and completely atrophied 3 to 4 months after ovariectomy. Uterine tubal cilia were absent in all the control gilts. Cytologic changes were not seen in the atrophied epithelium of ovariectomized gilts 1 day after estradiol treatment, but definite proliferative elements consisting of an extensive fibrillar meshwork encrusted with granules (60 to 80 nm) were observed in close association with the nuclear envelope and in the apical cytoplasm after 2 days of estradiol treatment. By day 3, enlarged electron-opaque granules referred to as condensation forms, undergoing various stages of depletion, were closely associated with radially arranged procentrioles. These associations have been referred to as generative complexes. The presence of many generative complexes indicates that maximal production of basal bodies can be expected after 3 days of treatment with estradiol. The depletion of the condensation forms produced hollow spheres with thin walls as the procentrioles grew in length and assembled their microtubules. Enlarged mature-appearing basal bodies were abundant in the cytoplasm after 3 days of estradiol treatment. These bodies aligned themselves linearly along the luminal surface of the cell. Small ciliary buds were then formed above the cell surface, and ciliary filamentogenesis occurred in the bud. Motile cilia were observed on day 3, but cilia numbers increased markedly between day 4 and days 5 and 7. Procentrioles were generated from the diplosomal centriole after 2 days of estradiol treatment. These observations have provided evidence for both ancentriolar and centriolar basal body replication in the ciliated cells of uterine tube of the gilt. Maximal secretory cell differentiation occurred after 3 days of estradiol treatment. Hypertrophy of cytoplasmic organelles was evident on day 3, but the number of secretory granules and amount of rough endoplasmic reticulum increased markedly on days 5 and 7. Close association of secretory granules, Golgi apparatus, and endoplasmic reticulum was evident after estadiol treatment. These data indicate that both ciliated and secretory cells are sensitive to estrogen.


Assuntos
Estradiol/farmacologia , Tubas Uterinas/ultraestrutura , Suínos/anatomia & histologia , Animais , Diferenciação Celular , Cílios/efeitos dos fármacos , Cílios/ultraestrutura , Grânulos Citoplasmáticos/ultraestrutura , Células Epiteliais , Epitélio/efeitos dos fármacos , Epitélio/ultraestrutura , Tubas Uterinas/efeitos dos fármacos , Tubas Uterinas/metabolismo , Feminino , Organoides/ultraestrutura
18.
Am J Vet Res ; 37(12): 1421-33, 1976 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-999069

RESUMO

Ultrastructural changes in the uterine tube (oviduct) of pregnant gilts have been investigated with special reference to the ciliated, secretory, and stromal cells. Tissue from the uterine tube ampulla and infundibulum was taken from 18 gilts at different stages of gestation (days 31, 36, 101, 102, 107, 110, and 112). Cilia were present throughout pregnancy, and deciliation was not apparent at any stage of gestation. The low epithelium of the uterine tube appeared similar to that of the luteal phase of the estrous cycle when corpora lutea were full grown. Prominent features at end of the gestation were numerous fibrous granules and basal bodies, indicating active formation of ciliary precursor organelles. Fibrogranular aggregates were also present in association with the basal bodies. In addition, numerous polyribosomes, mitochondria, and microtubules were encountered in the cytoplasm of ciliated cells at end of the gestation. The appearance of electron-opaque, fibrous granules during late pregnancy probably could be correlated with increasing endogenous levels of plasma estrogen. Intimate morphologic association between fibrous granules and basal bodies indicate that fibrous granules might provide precursor material for the development of cilia or rootlets. Characteristics ultrastructural changes observed in secretory cells during the estrous cycle were not discernible in secretory cells during pregnancy. The secretory cells appeared similar to those of the luteal phase of the estrous cycle. The apocrine secretory cells contained prominent, apical, cytoplasmic projections; pinching-off process of these protrusions was frequently observed during early and term gestation. Extruded nuclei along with other cytoplasmic organelles were also present, lying free in the tubal lumen. The endoplasmic reticulum was predominantly tubular in form. Synthesis, storage, and release of secretory granules were not apparent at early or late pregnancy. It is suggested that progesterone might have an inhibitory effect on the synthesis, storage, and release of secretory granules. Ultrastructural changes in stromal cells were not apparent at any stage of gestation. The stromal cells appeared similar to that of the luteal phase of the estrous cycle.


Assuntos
Tubas Uterinas/ultraestrutura , Suínos/anatomia & histologia , Animais , Cílios/ultraestrutura , Grânulos Citoplasmáticos/ultraestrutura , Células Epiteliais , Epitélio/ultraestrutura , Feminino , Gravidez , Prenhez , Suínos/fisiologia
19.
Am J Vet Res ; 37(8): 923-33, 1976 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-986123

RESUMO

Ultrastructural features of the uterine tube (oviduct) infundibulum of ewes have been studied, with special reference to cyclic changes in the ciliated and the secretory cells. Tissue from the uterine tube infundibulum was taken from 12 Rambouillet crossbreed ewes which were killed at intervals (days 1 (or estrus), 3, 9, 10, 12, and 16) throughout the estrous cycle. The presence of cilia was demonstrated throughout the estrous cycle, and true degeneration or loss of cilia was not apparent at any phase of the cycle. Presence of fibrous granules, which are supposedly related to basal body replication, was demonstrated in the apical cytoplasm of ciliated cells on day 1 of the estrous cycle. Small ciliary buds were especially present on day 1, indicating active formation of cilia during the follicular phase of the cycle. The presence of fibrous granules, basal bodies, and ciliary buds at estrus indicates that ciliogenesis in the ewe uterine tube is stimulated by high levels of endogenous estrogen. Rootlets were observed both during the follicular and the luteal phases of the cycle. The rootlets were about 1 mum long, and their fine structure indicates that they might function as anchoring structures for the motile cilia. The most striking feature during estrus was the occurrence of glycogen granules in the cytoplasm of ciliated and secretory cells. These granules were in the apical cytoplasm and basal region of some epithelial cells. They were minimal or absent during the luteal phase of the estrous cycle. The presence of electron-dense glycogen particles was clearly demonstrated within basal bodies. Possibly the glycogen within the basal bodies functions as a source of energy for ciliary movement and the cytoplasmic glycogen as nourishment for the ovum. The secretory cells also showed characteristic cytologic changes which were correlated with the phase of the estrous cycle. Maximal secretory cell differentiation was apparent during the follicular phase, at which time these cells were characterized by well-developed rough endoplasmic reticulum, numerous ribosomes, and secretory granules of varied size, shape, and density. A most remarkable feature of the granules was their membranous structure, consisting of concentric lamellae of equal dimensions. Typical extrusion of secretory granules into the tubal lumen was apparent during the follicular and the luteal phases of the estrous cycle. Cytoplasmic projections containing nuclei protruded into the tubal lumen and some were free in the lumen, especially during the luteal phase of the estrous cycle. The presence of a well-developed endoplasmic reticulum and numerous secretory granules during estrus indicate that secretion in the ewe uterine tube is presumably under the control of circulating high plasma concentrations of estrogen.


Assuntos
Estro , Tubas Uterinas/ultraestrutura , Ovinos/fisiologia , Animais , Cílios/ultraestrutura , Grânulos Citoplasmáticos/metabolismo , Grânulos Citoplasmáticos/ultraestrutura , Células Epiteliais , Epitélio/metabolismo , Epitélio/ultraestrutura , Tubas Uterinas/metabolismo , Feminino , Glicogênio/metabolismo , Gravidez , Ovinos/anatomia & histologia , Ovinos/metabolismo
20.
Am J Vet Res ; 37(9): 1001-10, 1976 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-962202

RESUMO

Ultrastructural details of prepubertal porcine uterine tube (oviduct) were studied in normal, growing gilts and compared with observations reported in other species. Tissues from the ampulla region of uterine tube were taken from 6 prepubertal gilts (106 to 139 days old) to determine cytodifferentiation of ciliated and secretory cells. The epithelium consisted of 2 distinctive cells, the ciliated and the secretory cells. Cilia were observed in the uterine tube of prepubertal gilts; however, degeneration of cilia was not observed in the present study. Most prominent observations were the occurrence of fibrous granules in the apical cytoplasm of ciliated cells. These fibrous granules contained electron-dense material and were present near basal bodies. The most unusual feature was the occurrence of procentrioles around a condensation form. These data indicate that ciliated cells are sensitive to estrogen. Intimate morphologic association between fibrous granules and basal bodies indicate that fibrous granules might provide precursor material for the development of cilia and rootlets. The cytoplasm of the secretory cells contained rough endoplasmic reticulum of tubular form and numerous ribosomes. Evidence for synthesis, storage, and release of secretory granules was not apparent. It is suggested that the secretory cells are not sensitive to the low, circulating concentration of plasma estrogen. The ultrastructure of the stromal cells and lymphatic capillary was described for the 1st time. The uterine tube stromal cells were characterized by prominent nucleus and a few cytoplasmic organelles. The lymphatic capillaries were distinguished by the blood capillaries, their much wider lumen, endothelium with an attenuated cytoplasm, absence of basal lamina, and overlapping and interdigitating intercellular junctions. The fine structure of the porcine uterine tube lymphatic capillary generally resembled that of other mammalian species.


Assuntos
Tubas Uterinas/ultraestrutura , Suínos/anatomia & histologia , Animais , Cílios/ultraestrutura , Grânulos Citoplasmáticos/ultraestrutura , Epitélio/ultraestrutura , Feminino , Sistema Linfático/ultraestrutura
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