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1.
Water Sci Technol ; 68(6): 1280-7, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24056424

RESUMO

One of the most effective mitigative approaches to eutrophication is the reduction of nutrient loading into water bodies. Bioremediation presents an economically viable and ecologically sustainable technology to nutrient pollution control taking advantage of the remarkable ability of plants and their associated microbial community to assimilate and remove nutrients from the environment. In this study, four emergent macrophytes (Cyperus haspan, Pandanus amaryllifolius, Pontederia cordata and Thalia geniculata) and two floating plants (Hygroryza aristata and Pistia stratiotes) were deployed in bank-side treatment beds and comparatively assessed for their remediative capabilities for nutrient control. P. stratiotes exhibited the highest removal efficiency for both nitrate and phosphate among the six plant species studied. Emergent macrophytes, P. amaryllifolius, C. haspan and P. cordata, were also found to be highly effective in nutrient uptake exhibiting removal efficiencies up to 100%. With the exception of T. geniculata, depletion of nutrients as a result of plant uptake significantly impeded the natural colonization of algae invariably leading to improvements in water quality in terms of turbidity and pH. Suppression of algae proliferation by T. geniculata was not preceded by a reduction in nutrient concentrations suggesting that T. geniculata may be directly inhibiting algal growth through allelopathy.


Assuntos
Magnoliopsida/metabolismo , Nitratos/metabolismo , Fosfatos/metabolismo , Poluentes da Água/metabolismo , Biodegradação Ambiental , Clorofila/metabolismo , Clorofila A , Eutrofização
2.
Artigo em Inglês | MEDLINE | ID: mdl-23947707

RESUMO

Laboratory batch and column experiments were carried out to examine the efficiency of algal-based treatment technique to clean-up wastewaters emanating from inductively coupled plasma-optical emission spectrometry (ICP-OES). Chemical characterization revealed the extreme complexity of the wastewater, with the presence of 14 different metals under very low pH (pH = 1.1), high conductivity (6.98 mS/cm), total dissolved solid (4.46 g/L) and salinity (3.77). Batch experiments using Sargassum biomass indicated that it was possible to attain high removal efficiencies at optimum pH of 4.0. Efforts were also made to continuously treat ICP-OES wastewater using up-flow packed column. However, swelling of Sargassum biomass leads to stoppage of column. To address the problem, Sargassum was mixed with sand at a ratio of 40: 60 on volume basis. Remarkably, the hybrid Sargassum-sand sorbent showed very high removal efficiency towards multiple metal ions with the column able to operate for 11 h at a flow rate of 10 mL/min. Metal ions such as Cu, Cd, and Pb were only under trace levels in the treated water until 11 h. The results of the treatment process were compared with trade effluent discharge standards. Further the process evaluation and cost analysis were presented.


Assuntos
Metais Pesados/metabolismo , Sargassum/metabolismo , Espectrofotometria Atômica , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Poluentes Químicos da Água/química , Adsorção , Biomassa , Dióxido de Silício/química , Eliminação de Resíduos Líquidos/economia , Eliminação de Resíduos Líquidos/instrumentação
3.
Water Res ; 46(4): 1337-45, 2012 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-22244273

RESUMO

Green (vegetated) roofs are emerging as practical strategies to improve the environmental quality of cities. However, the impact of green roofs on the storm water quality remains a topic of concern to city planners and environmental policy makers. This study investigated whether green roofs act as a source or a sink of various metals (Na, K, Ca, Mg, Al, Fe, Cu, Cd, Pb, Zn, Mn, Cr, Ni, Li and Co), inorganic anions (NO3-, NO2-, PO4(3-), SO4(2-), Cl-, F- and Br-) and cation (NH4+). A series of green roof assemblies were constructed. Four different real rain events and several artificial rain events were considered for the study. Results showed that concentrations of most of the chemical components in runoff were highest during the beginning of rain events and subsided in the subsequent rain events. Some of the important components present in the runoff include Na, K, Ca, Mg, Li, Fe, Al, Cu, NO3-, PO4(3-) and SO4(2-). However, the concentration of these chemical components in the roof runoff strongly depends on the nature of substrates used in the green roof and the volume of rain. Based on the USEPA standards for freshwater quality, we conclude that the green roof used in this study is reasonably effective except that the runoff contains significant amounts of NO3- and PO4(3-).


Assuntos
Materiais de Construção , Química Verde , Chuva , Eliminação de Resíduos Líquidos , Qualidade da Água , Ânions/análise , Cátions/análise , Condutividade Elétrica , Concentração de Íons de Hidrogênio , Metais/análise , Salinidade , Singapura , Estados Unidos , United States Environmental Protection Agency
4.
Chemosphere ; 80(3): 310-8, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20444492

RESUMO

The spatial and temporal distribution of various trace elements in water and suspended solids in urban runoff from residential and industrial sites was studied. 240 sequential urban runoff samples from 39 rain/storm events were collected, processed and analyzed for 13 elements (12 metals - Al, Co, Cd, Cr, Cu, Fe, Mn, Pb, Ni, Ti, V, and Zn, and one metalloid--As). The experimental protocol used in this study was validated using standard reference material (NIST 1648, urban particulate matter) and certified rain water samples. Good agreement was obtained between the certified and measured values. Al, Fe and Zn were found to be abundant in both residential and industrial runoffs. Some of the metals demonstrated first flush phenomena. Investigation of dissolved fraction, environmentally mobile fraction and total concentration for the 13 elements revealed that trace elements in industrial runoff were highly enriched as compared to those in the residential runoff. The environmentally mobile fraction was quite significant for most of the trace elements. Statistical correlations among the metals were studied, and principal component analysis (PCA) was used for identification of the major sources of the metals/metalloid in both residential and industrial runoffs. Crustal leaching, paints from building walls, and atmospheric deposition were found to be the main sources of metals/metalloid in runoff from the residential site while emissions from petrochemical and semiconductor industries, metal corrosion and vehicular emissions were the main sources of metals/metalloid in runoff from the industrial site. These results are presented and discussed in this paper.


Assuntos
Monitoramento Ambiental/métodos , Chuva , Poluentes do Solo/análise , Oligoelementos/análise , Poluentes Químicos da Água/análise , Análise de Componente Principal , Estações do Ano , Singapura , Urbanização
5.
Water Sci Technol ; 56(1): 277-85, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17711025

RESUMO

This study evaluated the potential use of brown seaweed Sargassum sp to sequester lead and copper (Pb(II) and Cu(ll)) from urban runoff based on batch as well as column experiments. The equilibrium data exhibited Langmuir isotherms. The adsorption capacity of this seaweed was found to be 196.1 mgg(-1) and 84.0 mg g(-1) for Pb(ll) and Cu(ll), respectively, which are in good agreement with those values obtained for the aqueous solution (188.6 mg g(-1) for Pb(ll) and 86.9 mg g(-1) for Cu(II)). The functional group analysis of the seaweed using FTIR demonstrated that the carboxyl functional groups are mainly responsible for biosorption. The cation exchange capacity of the biosorbent was 2.25 meq/g. This observation suggested that ion exchange mechanism is predominantly responsible for the metal ion uptake. The column study showed that the highest bed height and the lowest flow rate result in a substantial enhancement of the metals uptake with the biosorption uptake capacities being 264.3 mg Pb(ll) g(-1) and 86.0 mg Cu(ll) g(-1). In the binary system, the biosorption capacity was observed to be 208.7 mg Pb(ll) g(-1) and 61.0 mg Cu(II) g(-1). The predicted breakthrough curves by the Thomas adsorption model gave a good fit of the experimental data with r2 ranging from 0.92 to 0.99.


Assuntos
Cobre/metabolismo , Chumbo/metabolismo , Chuva/química , Sargassum/metabolismo , Cátions Bivalentes/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier
6.
Int J Fertil Menopausal Stud ; 39(4): 218-22, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7951405

RESUMO

OBJECTIVE: To assess changes in lipoprotein-lipid profile vis-a-vis putative risk of atherosclerotic diseases, among a group of hyperandrogenic women. SUBJECTS AND METHODS: Women studied were among those being screened for polycystic ovarian disease (PCOD) at the Reproductive Endocrinology Clinic of the institute. They all had oligomenorrhea/chronic anovulation as their problem and had clinical or laboratory evidence of hyperandrogenism, viz., hirsutism or elevated serum testosterone levels. Lipoprotein-lipid profiles obtained in 51 such women were compared with those of 11 controls with normal menstrual cycles and no evidence of hyperandrogenism. RESULTS: No significant changes were observed in any of the lipoprotein-lipid variables which could be attributed to hyperandrogenism per se. However, a combined effect of obesity and raised circulating androgens in causing a significant change in the lipoprotein-lipid profile (increased cholesterol, LDL-C/HDL-C, and cholesterol/HDL-C) was clearly discernible from the study. CONCLUSIONS: Hyperandrogenism by itself may not signal a risk for atherosclerotic diseases. However, the potential of such risk would be significantly enhanced if obesity is associated with high circulating levels of androgens.


Assuntos
Androgênios/sangue , Hiperandrogenismo/sangue , Lipoproteínas/sangue , Adulto , Análise de Variância , Análise Química do Sangue , Fatores de Confusão Epidemiológicos , Doença das Coronárias/epidemiologia , Feminino , Humanos , Hiperandrogenismo/fisiopatologia , Índia , Lipoproteínas/metabolismo , Obesidade/fisiopatologia , Fatores de Risco
7.
J Clin Lab Anal ; 7(2): 95-9, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8505702

RESUMO

Penicillinase (beta-lactamase) enzyme-linked immunosorbent assay (ELISA) for various reproductive hormones developed in the laboratory were found to have wide applicability in the fertility check clinic of the Institute. A need was thought to transform these assays into ready-to-use kit forms. Therefore, prototype ELISA kits for these hormones were developed and stability of the individual component was ascertained at various temperatures (room temperature, 37 degrees C and 2-8 degrees C). Stability studies were conducted on previously validated assay for pregnanediol-3 alpha-glucuronide (PdG). The studies showed that immunosorbents (antibody coated plates) are stable at room temperature for a period of 2 weeks, at 37 degrees C for 1 week and at 2-8 degrees C for a period of 9 months when preserved after treatment with glycerol solution. The lyophilised conjugate, standard and immunoassay buffer, colour reagent, and its substrate were stable at 37 degrees C up to 1 week and at room temperature up to 2 weeks and at 2-8 degrees C for a period of 6 months, during which the stability was studied.


Assuntos
Ensaio de Imunoadsorção Enzimática , Penicilinase/química , Kit de Reagentes para Diagnóstico , Estabilidade Enzimática
8.
Eur J Clin Chem Clin Biochem ; 30(5): 297-300, 1992 May.
Artigo em Inglês | MEDLINE | ID: mdl-1627727

RESUMO

An indirect ELISA for the estimation of urinary gonadotropins is described. Human menopausal gonadotropin is adsorbed on a microtitre plate, where it serves as an immunosorbent. The residual antigonadotropin antibody is captured by the immunosorbent after reaction with the sample or standard and detected with enzyme-labelled antispecies antibody (antirabbit gamma-globulin-horse radish peroxidase). The assay developed here is rapid and satisfies usual validatory criteria expected from an immunoassay. Moreover, it obviates the need for extraction of samples with acetone, as shown by the close agreement between the respective lutropin or follitropin concentrations in extracted and unextracted urine samples.


Assuntos
Gonadotropinas/urina , Menotropinas , Animais , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Hormônio Foliculoestimulante/urina , Humanos , Hormônio Luteinizante/urina , Coelhos
9.
Eur J Obstet Gynecol Reprod Biol ; 38(3): 213-6, 1991 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-2007447

RESUMO

Corpus luteal function was assessed by estimating pregnanediol 3-alpha-glucuronide (PdG) in three midluteal-phase urine samples collected from 85 women attending the infertility clinic. The previously established cut off limits based on PdG estimations were useful in detecting anovulation in 23 cases, corpus luteal adequacy in 42 cases and corpus luteum deficiency (CLD) in 20 cases. In 8 women CLD could be corrected with 50 mg of clomiphene citrate (CC) therapy whereas 6 women required 100 mg of CC and 3 pregnancies were achieved. This rapid screening method is thus useful in segregating a large number of women according to their ovulatory status and in the subsequent treatment of CLD.


Assuntos
Corpo Lúteo/metabolismo , Ensaio de Imunoadsorção Enzimática , Infertilidade Feminina/terapia , Detecção da Ovulação , Pregnanodiol/análogos & derivados , Clomifeno/farmacologia , Corpo Lúteo/efeitos dos fármacos , Feminino , Humanos , Masculino , Pregnanodiol/urina
10.
J Immunoassay ; 12(1): 83-98, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1904075

RESUMO

An antiserum to follicle stimulating hormone (FSH) obtained as a gift from National Institute of Health (NIH), U.S.A. could not be adsorbed on microtitre ELISA plates, although two other FSH antisera raised in authors' laboratory could be adsorbed. A good precision profile for the FSH assay using these three antisera could be achieved with only one separation system viz. solid phase anti rabbit gamma globulin (ARGG), out of the five separation systems tried. The study suggests that a few antisera used for radio-immunoassay (RIA) purposes may not by themselves get adsorbed on plastic plates. However, they could be effectively used for ELISA purposes using solid phase second antibody.


Assuntos
Ensaio de Imunoadsorção Enzimática/métodos , Hormônio Foliculoestimulante/análise , Adsorção , Anticorpos/isolamento & purificação , Estudos de Avaliação como Assunto , Hormônio Foliculoestimulante/imunologia , Humanos , Técnicas de Imunoadsorção
11.
J Appl Toxicol ; 9(6): 367-75, 1989 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2482307

RESUMO

Our previous studies indicated the involvement of some unidentified mechanisms, apart from the bioactivation phenomenon, in chlordecone (CD)-potentiated CCl4 hepatotoxicity and lethality. Recent studies revealed that hepatocellular regeneration is suppressed in CD + CCl4 toxicity. The present work is a continuation of our earlier work employing a partial hepatectomy model for stimulating hepatocellular division, in normal (N) or CD-treated (10 ppm for 15 days) rats. Male Sprague-Dawley rats maintained on an appropriate dietary protocol and undergoing sham (SH) or partial hepatectomies (PH) were employed. Hepatocellular regeneration was assessed by measuring the percentage mitotic figures and by autoradiography of liver sections from rats given 3H-thymidine in vivo. Hepatotoxicity was assessed by examining liver sections for necrotic cells, swollen cells and cells having lipid droplets. CCl4 (100 microliters kg-1)-induced histopathological alterations in CD-pretreated rats were significantly decreased in rats 2 days post-PH (PH2) as compared to SH rats or rats 7 days post-PH (PH7), indicating that amplification of CCl4 toxicity is significantly reduced when there is a greater regenerative activity. The percentage of mitoses as well as the percentage of labelled cells were significantly elevated at 2-6 h after CCl4 administration in N rats but remained suppressed in CD rats. In CD-pretreated PH2 rats where the percentage of mitoses and the percentage of labelled cells were many-fold greater when compared to SH or PH7 rats, a portion of the stimulated hepatocellular division decreased significantly at 2-6 h after CCl4 administration, but remained significantly greater when compared to basal level of regeneration.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Intoxicação por Tetracloreto de Carbono/fisiopatologia , Doença Hepática Induzida por Substâncias e Drogas/fisiopatologia , Clordecona/toxicidade , Inseticidas/toxicidade , Animais , Autorradiografia , Doença Hepática Induzida por Substâncias e Drogas/patologia , Sinergismo Farmacológico , Hepatectomia , Metabolismo dos Lipídeos , Fígado/patologia , Fígado/fisiopatologia , Regeneração Hepática , Masculino , Ratos , Ratos Endogâmicos
12.
Biochim Biophys Acta ; 1004(3): 309-20, 1989 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-2758025

RESUMO

Lysosomal phospholipid storage disorder in lung tissue was observed during chronic treatment with amphiphilic amine drugs. The prevailing and widely accepted mechanism of phospholipidosis is that amphiphilic drugs bind to phospholipids and make the phospholipids unsuitable substrates for the action of phospholipases. We investigated hydrophobic and hydrophilic binding of fifteen drugs to the phospholipid storage organelle, lung lamellar bodies, isolated from male Sprague-Dawley rats. Hydrophobic interactions were studied using 1,6-diphenyl-1,3,5-hexatriene as a fluorescent probe and hydrophilic binding was studied using 1-anilino-8-naphthalene sulfonate as a fluorescent probe. The binding parameters were calculated using Scatchard equations. Of the fifteen drugs used, nine drugs bound to the hydrophobic moiety of lamellar bodies. The order of binding capacities was promethazine greater than chloramphenicol greater than amiodarone = desethylamiodarone greater than promazine greater than chlorpromazine greater than trimipramine greater than propranolol greater than imipramine much greater than chlorphentermine, phentermine, chloroquine, chlorimipramine, cyclizine and chlorcyclizine. Two binding affinities were calculated for all the bound drugs. Binding affinities to hydrophilic sites of lamellar bodies were calculated in terms of emission coefficients for 1-anilino-8-naphthalene sulfonate in the presence of drugs. Hydrophilic binding was in the order chlorpromazine greater than chlorimipramine greater than promazine greater than trimipramine greater than imipramine greater than chlorcyclizine greater than propranolol greater than promethazine greater than chlorphentermine greater than cyclizine greater than phentermine greater than chloroquine much greater than chloramphenicol, amiodarone and desethylamiodarone. The binding affinities of chlorinated analogs were stronger to hydrophilic sites when compared to the parent compound. Amiodarone, which is known to induce pulmonary phospholipidosis and its major non-polar metabolite, desethylamiodarone, bound strongly to lamellar bodies. These two drugs also inhibit phospholipases in vitro. The drugs with weak phospholipidosis-inducing capacity and extensive in vivo metabolism, namely, imipramine, chlorpromazine and promazine, also bound strongly to lamellar bodies with hydrophilic as well as hydrophobic interactions. On the other hand, chloroquine, which is known to induce phospholipidosis and to inhibit phospholipases, did not bind to lamellar bodies. Two major conclusions could be drawn from this study: one is that the drug interactions with isolated lamellar bodies could be studied using membrane fluorescence probes, 1,6-diphenyl-1,3,5-hexatriene and 1-anilino-8-naphthalene sulfonate; second is that the amphiphilic drugs bind to lamellar bodies, as reported for phospholipid vesicles, and the binding of drugs to lamellar bodies could be correlated with their phospholipidosis-inducing capacity only if


Assuntos
Aminas/metabolismo , Pulmão/metabolismo , Organelas/metabolismo , Naftalenossulfonato de Anilina , Animais , Difenilexatrieno , Técnicas In Vitro , Pulmão/ultraestrutura , Masculino , Microscopia Eletrônica , Fosfolipídeos , Ratos , Ratos Endogâmicos , Espectrometria de Fluorescência
13.
Indian J Med Res ; 90: 254-7, 1989 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2620950

RESUMO

A rapid, simple, two-step test for the detection of ovulation has been developed. The test is based on ELISA of pregnanediol glucuronide, a metabolite of progesterone, in urine collected specifically over a period of 3 h. The test is completed in 20 min and the results are assessed visually by naked eye.


Assuntos
Ovulação/fisiologia , Pregnanodiol/urina , Adolescente , Adulto , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos
14.
J Appl Physiol (1985) ; 66(5): 2437-45, 1989 May.
Artigo em Inglês | MEDLINE | ID: mdl-2745304

RESUMO

Chronic administration of amphiphilic drugs to rats induces pulmonary phospholipidosis (P), a disease characterized by accumulation of phospholipids and large foamy macrophages in alveolar spaces. We investigated whether P induced by chlorphentermine (CPH) causes changes in lung volumes and mechanics in this species. Groups of rats were fed CPH (50 mg.kg-1.day-1) for 1, 2, 3, 5, 9, and 14 wk. After each treatment period, lung volumes and mechanics were studied in the anesthetized, paralyzed, supine rat. Partial pressure-volume (PV) curves were developed at 3 and 6 ml above functional residual capacity (FRC; PV3, PV6), followed by maximal [up to total lung capacity (TLC)] PV curves. FRC was determined by saline displacement. Lungs were then fixed for histopathological examination. A subgroup of animals was allowed a recovery period of 6 wk, after the 9 wk of CPH administration. Pair-fed rats served as controls (CTR) at each time point. Lung weight increased in CPH-treated (CPH-T) rats from 1.5 +/- 0.2 (SD) g at week 1 to 5.8 +/- 1.4 g at week 14, reflecting the development of P. TLC, FRC, transpulmonary pressure at FRC, the shape of maximal PV curves, and static expiratory lung compliance computed from maximal PV data points did not change in CPH-T rats. However, partial PV curves of CPH-T lungs (particularly PV3) were shifted downward and to the right of those of CTR at 2, 3, 5, and 9 wk, indicating increased recoil pressure in phospholipidotic lungs at these time points.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Clorfentermina/toxicidade , Pulmão/patologia , Fentermina/análogos & derivados , Fosfolipídeos/fisiologia , Animais , Peso Corporal/efeitos dos fármacos , Pulmão/efeitos dos fármacos , Pulmão/fisiologia , Complacência Pulmonar , Medidas de Volume Pulmonar , Masculino , Tamanho do Órgão/efeitos dos fármacos , Fosfolipídeos/análise , Ratos , Ratos Endogâmicos , Valores de Referência , Testes de Função Respiratória
15.
Arch Toxicol ; 63(5): 367-75, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2479360

RESUMO

Previous histomorphometric studies led us to hypothesize that suppression of hepatocellular regeneration and the repair of the hepatolobular architecture was involved besides bioactivation phenomenon in the progressive and irreversible phase of toxicity resulting from CD + CCl4 interaction. We have recently observed significant protection from CD potentiated CCl4 toxicity in animals which are stimulated for active hepatocellular regeneration. The present work is an extension of our earlier histomorphometric investigation, taking 3H-thymidine (3H-T) incorporation as a biochemical parameter to assess hepatocellular regeneration followed by autoradiographic analysis of liver sections in normal (N) or chlordecone (CD) treated (10 ppm in diet for 15 days) male rats undergoing sham (SH) or partial hepatectomies (PH). Initial experiments established that in normal (N) rats, greatest 3H-T incorporation into hepatocellular nuclear DNA occurs at 2 days post-PH which returns to basal levels by 7 days. CD treatment alone did not change this phenomenon. 3H-T incorporation into nuclear DNA and the percentage of labelled cells as evidenced by autoradiography of liver sections were significantly elevated in N rats at 1-2 h after CCl4 (100 microliters/kg) administration and returned to basal level by 6 h. Serum enzymes (AST and ALT) in N rats undergoing SH and PH were not altered, but were significantly elevated in CD rats following CCl4 (100 microliters/kg) administration. CCl4-induced serum enzyme elevations were significantly lower in 2 days post-PH (PH2) rats when compared to SH rats or 7 days post-PH (PH7) rats maintained on CD diet, indicating that CD potentiated CCl4 hepatotoxicity is significantly reduced in livers stimulated for regenerative activity by PH.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Intoxicação por Tetracloreto de Carbono/fisiopatologia , Doença Hepática Induzida por Substâncias e Drogas/fisiopatologia , Clordecona/toxicidade , Regeneração Hepática/efeitos dos fármacos , Animais , Autorradiografia , Intoxicação por Tetracloreto de Carbono/enzimologia , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/enzimologia , DNA/biossíntese , Dieta , Sinergismo Farmacológico , Hepatectomia , Inseticidas , Masculino , Ratos , Ratos Endogâmicos , Timidina/metabolismo
16.
Toxicol Pathol ; 17(3): 494-505, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2814225

RESUMO

CCl4 is a hepatotoxic haloalkane, capable of producing hepatocellular fatty degeneration and centrilobular necrosis. Previous reports indicate induction of liver regeneration after 36-48 hr of CCl4 treatment, which is considered as a secondary effect. The present investigation was undertaken to evaluate the primary effects of CCl4 on hepatic DNA synthesis and to correlate liver regeneration with CCl4 toxicity. These studies were conducted in normal and actively regenerating livers using male Sprague-Dawley rats undergoing sham operation (SH), or partial (70%) hepatectomy (PH). Incorporation of 3H-thymidine (3H-T) in hepatocellular nuclear DNA and autoradiographic analyses of liver sections served as indices for hepatocellular regeneration. Initial experiments established that peak regeneration occurs at 2 days post-PH (PH2) and liver regeneration phases out by 7 days post-PH (PH7). SH and PH rats were challenged with a single ip dose of either corn oil vehicle or CCl4 at either 0.1 ml/kg (to represent subtoxic dose) or 2.5 ml/kg (to represent toxic dose). The low dose of CCl4 was not toxic and did not alter 3H-T incorporation and percentage labelled cells at 6 or 24 hours after administration to SH, PH2 or PH7 groups, indicating that there was no interference with PH-stimulated hepatocellular regeneration. The high dose of CCl4 was significantly hepatotoxic and lethal in SH rats, while in PH2 rats both hepatotoxic and lethal effects were significantly decreased. 3H-T incorporation as well as percentage labelled cells, highly stimulated by PH, were significantly decreased by high dose of CCl4. However, hepatocellular regeneration in PH2 rats treated with high dose of CCl4 was still significantly higher than SH or PH7 groups by virtue of the stronger stimulatory effect of PH. In PH7 rats, where hepatocellular regeneration had returned to the SH level, the hepatotoxic and lethal effects of the large dose of CCl4 were also restored. These findings show that the progressive phase of a single high dose of CCl4 injury which normally culminates in hepatotoxic and lethal effects is significantly mitigated by previously stimulated hepatocellular regeneration. High dose of CCl4 suppresses hepatocellular regeneration at early time points after administration in contrast to the smaller subtoxic dose of CCl4. By virtue of the much stronger stimulatory effect, PH results in the protection against the hepatotoxic and lethal effects of CCl4 despite the obtunding effects of the high dose on hepatocellular regeneration.


Assuntos
Intoxicação por Tetracloreto de Carbono/fisiopatologia , Doença Hepática Induzida por Substâncias e Drogas/fisiopatologia , Hepatectomia , Regeneração Hepática , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Doença Hepática Induzida por Substâncias e Drogas/patologia , DNA/metabolismo , Fígado/metabolismo , Fígado/patologia , Masculino , Ratos , Ratos Endogâmicos , Timidina/farmacologia
17.
J Biol Stand ; 17(1): 35-40, 1989 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2921252

RESUMO

The variation in the estimates of urinary pregnanediol glucuronide obtained by ELISA with 12 polyclonal antisera has been assessed. Of the 12 antisera, eight gave values comparable with each other and could be used interchangeably in the ELISA. Thus a large stock of polyclonal antibody which gave consistent values was generated and can now be used in diagnostic ELISA over a long period of time. This procedure is more economical than the development of monoclonal antibodies for the same purpose.


Assuntos
Anticorpos/normas , Ensaio de Imunoadsorção Enzimática , Pregnanodiol/análogos & derivados , Animais , Formação de Anticorpos , Imunização , Pregnanodiol/análise , Pregnanodiol/imunologia , Coelhos
18.
Toxicol Appl Pharmacol ; 96(2): 324-35, 1988 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-3194918

RESUMO

The purpose of the present investigation was to understand the acute effects of cigarette smoke on glutathione (GSH) metabolism and on utilization of external thiols by cigarette smoke-exposed, perfused rat and rabbit lungs. Most of the experiments were carried out using freshly drawn cigarette smoke. However, cigarette smoke condensate was used in some perfusions for the comparison of the effects between the types of exposures on utilization of external thiols. Cigarette smoke decreased GSH levels significantly (50%) without any increase in glutathione disulfide (GSSG) in both rabbit and rat lungs. In smoke-exposed rabbit lungs, protein thiol groups (protein-SH) decreased significantly (17%) without a significant change in protein-GSH mixed disulfides. However, in the rat lungs, cigarette smoke did not decrease protein-SH and protein-GSH mixed disulfides, indicating species variation in the effect of cigarette smoke. Cigarette smoke inhibited selenium-dependent and -independent GSH peroxidase activities in the rat lung (33%), but not in the rabbit lung. GSH S-transferase and GSSG reductase activities were not altered in cigarette smoke-challenged rabbit and rat lungs. gamma-Glutamylcysteine synthetase and glucose-6-phosphate dehydrogenase activities were significantly lower in smoke-exposed rat lungs as against control lungs, indicating that rat lung enzymes were more susceptible to the effects of cigarette smoke when compared to those of rabbits. N-Acetylcysteine, but not GSH, added to the perfusate significantly protected rabbit lung from smoke-induced GSH depletion. Smoke condensate added to the perfusate also caused GSH depletion in rabbit lung, and GSH or N-acetylcysteine added to the perfusion medium protected the lung indicating that GSH in the media directly interacts with condensate in the media before coming in contact with cellular GSH. These results indicate that acute smoke inhalation decreases pulmonary GSH and that the decreased GSH was not related to disulfide formation. Inhibited GSH synthesis in rat lung could account for the loss of GSH in part after exposure to cigarette smoke. The alternative pathway of GSH utilization could be conjugation with electrophilic smoke components. Thiols, like N-acetylcysteine, were protective against cigarette smoke-induced damage to the rabbit lung. The mechanism could be either by the increased GSH synthesis or by the direct delivery of sulfhydryls from N-acetylcysteine.


Assuntos
Glutationa/metabolismo , Pulmão/enzimologia , Fumar/metabolismo , Compostos de Sulfidrila/metabolismo , Acetilcisteína/farmacologia , Animais , Glucosefosfato Desidrogenase/metabolismo , Glutationa/análogos & derivados , Dissulfeto de Glutationa , Glutationa Peroxidase/metabolismo , Homeostase , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Masculino , Coelhos , Ratos , Ratos Endogâmicos
19.
Int J Gynaecol Obstet ; 27(1): 107-11, 1988 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2905284

RESUMO

Estimations of urinary estrone glucuronide, pregnanediol glucuronide and human chorionic gonadotrophin were carried out by ELISA to see their potential in predicting an abnormal outcome in cases with vaginal bleeding in early pregnancy. Reference values were set up with samples from women without bleeding in present or past pregnancies and with normal ultrasonic findings. None of the parameters were found to be sensitive enough to predict an abnormal outcome. However, predictability of an abnormal value was found to be 95% for estrone-3-glucuronide (E1G), 93% for pregnanediol glucuronide (PdG) and 87% for human chorionic gonadotrophin (hCG).


Assuntos
Ameaça de Aborto/urina , Gonadotropina Coriônica/urina , Estrona/análogos & derivados , Pregnanodiol/análogos & derivados , Aborto Retido/urina , Ensaio de Imunoadsorção Enzimática , Estrona/urina , Feminino , Humanos , Gravidez , Pregnanodiol/urina
20.
J Pharmacol Exp Ther ; 246(1): 150-7, 1988 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3392651

RESUMO

Binding characteristics of nine amphiphilic drugs, which induce pulmonary phospholipidosis, to L-alpha-dipalmitoyl phosphatidylcholine (DPPC) vesicles were studied using fluorescence probes, 1,6-diphenyl-1,3,5-hexatriene and 1-anilino-8-naphthalene sulfonate (ANS) for hydrophobic and hydrophilic interactions, respectively. Drug binding to DPPC was quantitated using Scatchard analysis. The tested drugs bound to DPPC with different capacities. The order of binding capacity to hydrophobic site of DPPC using 1,6-diphenyl-1,3,5-hexatriene as fluorescence probe was promethazine greater than amiodarone greater than chlorpromazine greater than chloramphenicol greater than imipramine greater than trimipramine greater than propranolol much greater than chloroquine and chlorphentermine. Two binding affinities were evident for amiodarone, chlorpromazine, imipramine, trimipramine and promethazine. The order of binding strength at high affinity site was amiodarone greater than trimipramine greater than chlorpromazine greater than promethazine greater than imipramine. The order of drug binding capacity using ANS as fluorescence probe was chlorphentermine greater than trimipramine greater than propranolol much greater than amiodarone, chloroquine and chloramphenicol. Each of these drugs displayed a single binding affinity. Imipramine and chlorpromazine at 1 mM and higher concentrations showed intense fluorescence with ANS (5-20 microM) in the absence of DPPC indicating an interaction of these drugs with ANS. Chloroquine did not bind to either sites on DPPC. The binding of these drugs and their interactions with hydrophobic or hydrophilic sites of DPPC were correlated with their capacity to induce pulmonary phospholipidosis. These results indicate that not all the drugs which bind to DPPC in vitro induce phospholipidosis in vivo.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Lipidoses/induzido quimicamente , Pneumopatias/induzido quimicamente , Lipídeos de Membrana/metabolismo , Fosfolipídeos/metabolismo , Tensoativos/metabolismo , Amiodarona/efeitos adversos , Amiodarona/metabolismo , Naftalenossulfonato de Anilina , Sítios de Ligação , Cloranfenicol/efeitos adversos , Cloranfenicol/metabolismo , Cloroquina/efeitos adversos , Cloroquina/metabolismo , Clorpromazina/efeitos adversos , Clorpromazina/metabolismo , Difenilexatrieno , Imipramina/efeitos adversos , Imipramina/metabolismo , Prometazina/efeitos adversos , Prometazina/metabolismo , Propranolol/efeitos adversos , Propranolol/metabolismo , Tensoativos/efeitos adversos , Trimipramina/efeitos adversos , Trimipramina/metabolismo
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