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1.
J Surg Case Rep ; 2017(3): rjx052, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28458858

RESUMO

Gallbladder perforation with subsequent gallstone spillage can occur with higher frequency in laparoscopic cholecystectomy than in traditional open approach. Gallstone abscess formation from stone spillage post-cholecystectomy is extremely rare. We present a case of para-spinal abscess formation 5 years after spilled gallstones following laparoscopic cholecystectomy.

2.
Scott Med J ; 59(2): e21-2, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24700107

RESUMO

Minimal inflammation of tissues can occur following skin closure with a foreign material. This foreign body reaction can lead to granuloma formation. We report the case of a middle-aged man who, having undergone laparoscopic surgery and had the port site wounds closed with skin glue, was detected to have a non-healing wound. A crystal mass protruding from the incision site was confirmed histologically as a chronic granulomatous reaction to skin glue. A foreign body granulomatous reaction to skin glue has not been described in the literature.


Assuntos
Fundoplicatura/métodos , Granuloma/etiologia , Herniorrafia/efeitos adversos , Inflamação/etiologia , Laparoscopia/efeitos adversos , Complicações Pós-Operatórias/patologia , Adesivos Teciduais/efeitos adversos , Granuloma/imunologia , Humanos , Inflamação/imunologia , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/imunologia , Resultado do Tratamento , Cicatrização
3.
Int J Breast Cancer ; 2011: 413949, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22295221

RESUMO

Breast cancer is the most frequent malignancy in women accounting for approximately 32% of all cancers, with a lifetime risk of 1 in 10. It causes considerable morbidity and mortality. Recently, the survival rate has dramatically increased due to early detection of the disease and improvement in the treatment measures. However, more than 30% of the patients develop metastatic diseases following surgical treatment, radiotherapy, hormonal therapy, or chemotherapy. Distant spread is usually found in bones, lungs, liver, brain and skin. Rarely, it spreads to bowel, spleen, gallbladder, pancreas, urinary bladder, and eyes. Breast cancer is the second commonest primary tumour responsible for gastrointestinal metastases after malignant melanoma. We report a case of a Caucasian female who developed an intestinal obstruction secondary to metastatic deposits to the small bowel and later to the rectum from breast lobular carcinoma 2 years after mastectomy, axillary clearance, radiotherapy, hormonal therapy, and transverse rectus abdominis myocutaneous (TRAM) flap for reconstruction.

4.
Int J Toxicol ; 27(4): 303-12, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18821393

RESUMO

Robust assessments of the nonclinical safety profile of biopharmaceuticals are best developed on a scientifically justified, case-by-case basis, with consideration of the therapeutic molecule, molecular target, and differences/similarities between nonclinical species and humans (ICH S6). Significant experience has been gained in the 10 years ensuing since publication of the ICH S6 guidance. In a PhRMA-FDA-sponsored workshop, "Nonclinical Aspects of Biopharmaceutical Development," industry and US regulatory representatives engaged in exploration of current scientific and regulatory issues relating to the nonclinical development of biopharmaceuticals in order to share scientific learning and experience and to work towards establishing consistency in application of general principles and approaches. The proceedings and discussions of this workshop confirm general alignment of strategy and tactics in development of biopharmaceuticals with regard to such areas as species selection, selection of high doses in toxicology studies, selection of clinical doses, the conduct of developmental and reproductive toxicity (DART) studies, and assessment of carcinogenic potential. However, several important aspects, including, for example, appropriate use of homologues, nonhuman primates, and/or in vitro models in the assessment of risk for potential developmental and carcinogenic effects, were identified as requiring further scientific exploration and discussion.


Assuntos
Fatores Biológicos , Química Farmacêutica , Animais , Humanos , Estados Unidos , United States Food and Drug Administration
5.
Acta Paediatr ; 93(3): 350-5, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15124838

RESUMO

AIMS: To evaluate the thermal responses and weight gain in preterm infants nursed in a cot on a heated, water-filled mattress (HWM) compared with infants receiving care in an air-heated incubator and to compare mothers' stress, anxiety levels and perceptions of their infants in the two groups. METHODS: Stable preterm infants weighing 1300 to 1500 g were enrolled, being randomly allocated to either the study group (n = 41) receiving care in a cot on an HWM, or the control group (n = 33) receiving incubator care. The mean daily body temperature and episodes of cold stress and hyperthermia were recorded. Weight gain (g kg(-1) body weight d(-1)) was also calculated. The mothers completed questionnaires on their perceptions of their infants, and their anxiety and stress levels before randomization, and 2-3 wk later during the trial. RESULTS: The mean body temperature was similar for the first week of the trial (study group 36.9 degrees C vs controls 36.9 degrees C). There were no significant differences in the incidence of cold stress, while more hyperthermic episodes were seen in the study group (p = 0.03). There were no significant differences in weight gain during the first (study group 21.4 g vs controls 19.6 g) or second weeks of the trial (study group 20.5 g vs controls 19.2 g). Neonatal morbidity did not differ between the groups. There were no differences in mothers' perceptions of their babies, or feelings of stress or anxiety. CONCLUSION: There were no differences between infants cot-nursed on an HWM and those receiving incubator care, with the exception of episodes of high temperature. The results suggest that the HWM may be used safely for low-weight preterm infants.


Assuntos
Leitos , Temperatura Corporal , Incubadoras para Lactentes , Recém-Nascido Prematuro , Humanos , Recém-Nascido , Recém-Nascido Prematuro/fisiologia , Aumento de Peso
6.
J Pediatr Orthop ; 23(1): 99-101, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12499953

RESUMO

The authors present a series of seven patients who have a diagnosis fitting that of combined ipsilateral facial and somatic hemiatrophy. Diagnostic features include facial, tongue, and ear asymmetry and associated decreases in length and size of the ipsilateral limbs. The symptomatic problems related to leg length discrepancy can be addressed in the usual fashion, and this condition does not appear to progress to large leg length discrepancies. The cosmetic side of this disorder is often concerning: it is the most reliable identification of the existence of this condition and is present from birth. Facial hemiatrophy is mild and does not appear to be progressive. The hemiatrophies probably have a multifactorial pathogenesis that most likely has at its basis a genetic cause.


Assuntos
Hemiatrofia Facial/diagnóstico , Desigualdade de Membros Inferiores/diagnóstico , Anormalidades Múltiplas/diagnóstico , Adolescente , Adulto , Distribuição por Idade , Alongamento Ósseo/métodos , Criança , Pré-Escolar , Estudos de Coortes , Hemiatrofia Facial/epidemiologia , Hemiatrofia Facial/terapia , Feminino , Humanos , Incidência , Lactente , Desigualdade de Membros Inferiores/epidemiologia , Desigualdade de Membros Inferiores/cirurgia , Masculino , Prognóstico , Sistema de Registros , Medição de Risco , Distribuição por Sexo
7.
Inhal Toxicol ; 14(12): 1187-213, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12454786

RESUMO

Episodic elevation of air pollutants may exacerbate respiratory distress associated with chronic obstructive pulmonary disease (COPD), yet few experiments have been performed to determine how continuously polluted atmospheres may contribute to the etiology of COPD, in general and pulmonary emphysema in particular. This study describes the effects of concurrent exposure to ozone (O(3)) in the pathogenesis of cigarette smoke (CS)-induced emphysema in the mouse. Female B6C3F1 mice were whole-body exposed either to filtered air (FA) or to mainstream CS at a concentration of 250 mg total particulate material/m(3) for 6 h/day, 5 days/wk for 15 or 32 wk. Concurrently, mice were exposed either to FA or to O(3) at 0.3 ppm for 8 h/night, 5 nights/wk for the same time periods. At necropsy, mouse lungs were lavaged, and bronchoalveolar lavage fluid (BALF) was analyzed for inflammatory cell numbers, total protein, lactate dehydrogenase (LDH) and alkaline phosphatase (AP) activities, superoxide production by isolated alveolar macrophages, glutathione content, inflammatory cytokines, and proteolytic activity. Other lungs were inflated at constant pressure for 6 h with formalin for fixation, routine histopathology, and stereology. After 32 wk of exposure, CS with or without concurrent O(3) exposure produced stereologic evidence of emphysema as previously described. Concurrent O(3) exposure did not worsen any of these parameters, nor did O(3) by itself cause stereologic changes that were consistent with emphysema. The O(3) exposure caused only slight elevations of BALF macrophages, while CS exposure caused marked increases in the numbers of both BALF macrophages and neutrophils. Neutrophils in the BALF in response to CS exposure were also more numerous at 32 wk than at 15 wk. Exposure to CS caused an increase in BALF total protein, LDH, AP, and interleukin (IL)-1beta. After 32 wk, CS exposure was associated with decreased superoxide production from isolated alveolar macrophages. The CS exposure elevated BALF total glutathione primarily at 15 wk. Overall, O(3) had little effect on endpoints that were significantly affected by CS exposure. We conclude that concurrent O(3) exposure has no effect on the induction of emphysema by CS in this animal model.


Assuntos
Ozônio/toxicidade , Enfisema Pulmonar/induzido quimicamente , Poluição por Fumaça de Tabaco/efeitos adversos , Animais , Peso Corporal , Líquido da Lavagem Broncoalveolar/química , Líquido da Lavagem Broncoalveolar/citologia , Citocinas/análise , Endopeptidases/metabolismo , Feminino , Glutationa/metabolismo , Exposição por Inalação/efeitos adversos , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Pulmão/patologia , Macrófagos Alveolares/efeitos dos fármacos , Macrófagos Alveolares/metabolismo , Camundongos , Enfisema Pulmonar/metabolismo , Enfisema Pulmonar/patologia , Superóxidos/metabolismo , Fatores de Tempo
8.
Inhal Toxicol ; 14(10): 1017-48, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12396409

RESUMO

There is increasing interest in diesel fuels derived from plant oils or animal fats ("biodiesel"), but little information on the toxicity of biodiesel emissions other than bacterial mutagenicity. F344 rats were exposed by inhalation 6 h/day, 5 days/wk for 13 wk to 1 of 3 dilutions of emissions from a diesel engine burning 100% soybean oil-derived fuel, or to clean air as controls. Whole emissions were diluted to nominal NO(x) concentrations of 5, 25, or 50 ppm, corresponding to approximately 0.04, 0.2, and 0.5 mg particles/m(3), respectively. Biologically significant, exposure-related effects were limited to the lung, were greater in females than in males, and were observed primarily at the highest exposure level. There was a dose-related increase in the numbers of alveolar macrophages and the numbers of particles in the macrophages, as expected from repeated exposure, but no neutrophil response even at the highest exposure level. The macrophage response was reduced 28 days after cessation of the exposure. Among the high-level females, the group mean lung weight/body weight ratio was increased, and minimal, multifocal bronchiolar metaplasia of alveolar ducts was observed in 4 of 30 rats. Lung weights were not significantly increased, and metaplasia of the alveolar ducts was not observed in males. An increase in particle-laden macrophages was the only exposure-related finding in lungs at the intermediate and low levels, with fewer macrophages and fewer particles per macrophage at the low level. Alveolar histiocytosis was observed in a few rats in both exposed and control groups. There were statistically significant, but minor and not consistently exposure-related, differences in body weight, nonpulmonary organ weights, serum chemistry, and glial fibrillary acidic protein in the brain. There were no significant exposure-related effects on survival, clinical signs, feed consumption, ocular toxicity, hematology, neurohistology, micronuclei in bone marrow, sister chromatid exchanges in peripheral blood lymphocytes, fertility, reproductive toxicity, or teratology. This study demonstrated modest adverse effects at the highest exposure level, and none other than the expected physiological macrophage response to repeated particle exposure at the intermediate level.


Assuntos
Óleos Combustíveis/efeitos adversos , Óleo de Soja , Testes de Toxicidade , Emissões de Veículos/toxicidade , Administração por Inalação , Animais , Relação Dose-Resposta a Droga , Feminino , Exposição por Inalação , Pulmão/efeitos dos fármacos , Pulmão/patologia , Macrófagos Alveolares/efeitos dos fármacos , Macrófagos Alveolares/patologia , Masculino , Tamanho do Órgão/efeitos dos fármacos , Tamanho da Partícula , Ratos , Ratos Endogâmicos
9.
Br J Surg ; 89(5): 579-85, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-11972547

RESUMO

BACKGROUND: Combined liver resection and local ablation may offer the only chance of cure to patients with liver metastases who are presently deemed unresectable because of a single awkwardly placed metastasis. By definition, such a metastasis is often close to a major vein. An ablative technique is needed that is both predictable and safe in such a circumstance. METHODS: Electrolytic liver lesions were created in 21 pigs using platinum electrodes, connected to a direct current generator. Both electrolytic 'dose' and electrode separation were varied to produce different sized lesions. The 'dose' was correlated with the volume of necrosis and any vascular damage was determined histologically. RESULTS: There was a significant (P < 0.001) correlation between the electrolytic 'dose' and the volume of liver necrosis. For a given 'dose' the volume of necrosis was less when the electrodes were together, rather than separated. Liver enzymes were only transiently deranged. There were no significant vascular injuries. CONCLUSION: Predictable and reproducible necrosis is produced by electrolysis in the pig liver. The treatment appears to cause little or no damage to immediately adjacent liver or major vascular structures and, when combined with resection, may offer the chance of a cure to many patients who are currently unresectable.


Assuntos
Eletrodos , Eletrólitos/uso terapêutico , Neoplasias Hepáticas/secundário , Alanina Transaminase/metabolismo , Animais , Aspartato Aminotransferases/metabolismo , Feminino , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/cirurgia , Necrose , Valor Preditivo dos Testes , Suínos , gama-Glutamiltransferase/metabolismo
10.
Water Res ; 35(6): 1387-98, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11317885

RESUMO

The effect of ultraviolet radiation from low- and medium-pressure mercury arc lamps on Cryptosporidium parvum oocysts was studied using a collimated beam apparatus. Experiments were conducted using parasites suspended in both filtered surface water and phosphate buffered laboratory water. Inactivation of oocysts was measured as reduction in infectivity using a CD-1 neonatal mouse model and was found to be a non-linear function of UV dose over the range of germicidal doses tested (0.8-119 mJ/cm2). Oocyst inactivation increased rapidly with UV dose at doses less than 25 mJ/cm2 with two and three log-units inactivation at approximately 10 and 25 mJ/cm2, respectively. The cause of significant leveling-off and tailing in the UV inactivation curve at higher doses was not determined. Maximum measured oocyst inactivation ranged from 3.4 to greater than 4.9 log-units and was dependent on different batches of parasites. Water type and temperature, the concentration of oocysts in the suspension, and the UV irradiance did not have significant impacts on oocyst inactivation. When compared on the basis of germicidal UV dose, the oocysts were equally sensitive to low- and medium-pressure UV radiation. With respect to Cryptosporidium, both low- and medium-pressure ultraviolet radiation are attractive alternatives to conventional chemical disinfection methods in drinking water treatment.


Assuntos
Cryptosporidium parvum/efeitos da radiação , Raios Ultravioleta , Água/parasitologia , Animais , Animais Recém-Nascidos , Cryptosporidium parvum/crescimento & desenvolvimento , Cryptosporidium parvum/patogenicidade , Relação Dose-Resposta à Radiação , Camundongos , Temperatura
11.
Water Res ; 35(18): 4339-48, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11763036

RESUMO

Inactivation of bovine-derived C. parvum oocysts was studied at bench-scale in oxidant demand free 0.05 M phosphate buffer using free chlorine alone or ozone followed by free chlorine at temperatures of 1 degrees C, 10 degrees C and 22 degrees C at pH 6. Animal infectivity using neonatal CD-1 mice was used for evaluation of oocyst viability after treatment. Kinetic models based on the linear Chick-Watson model were developed for free chlorine inactivation and ozone/free chlorine sequential inactivation for 0.4 or 1.6 log-units of ozone primary kill. At 22 degrees C. ozone pre-treatment increased the efficacy of free chlorine for about 4-6 times depending on the level of ozone primary kills. Gross kills of the ozone/free chlorine sequential inactivation were a function of ozone primary kills and increased linearly with the free chlorine C(avg)t (arithmetic average of the initial and final residual x contact time) product. Temperature was critical for both single and sequential inactivation, and the efficacy of free chlorine after 1.6 log-units of ozone primary inactivation decreased by a factor of 1.8 for every 10 degrees C temperature decrease. Given an ozone primary kill of 1.6 log-units, the free chlorine C(avg)t products required for a gross kill of 3.0 log-units were 1000, 2000 and 3,300 mgmin/L for 22 degrees C. 10 degrees C and 1degrees C, respectively.


Assuntos
Cloro/química , Cryptosporidium parvum/patogenicidade , Modelos Teóricos , Oxidantes Fotoquímicos/química , Ozônio/química , Purificação da Água/métodos , Animais , Bovinos , Cinética , Temperatura
12.
Chest ; 117(5 Suppl 1): 246S-7S, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10843930
13.
J Pharmacol Exp Ther ; 293(1): 166-71, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10734166

RESUMO

Chronic exposure of mice and rats to cigarette smoke affects T-cell responsiveness that may account for the decreased T-cell proliferative and T-dependent antibody responses in humans and animals exposed to cigarette smoke. However, the mechanism by which cigarette smoke affects the T cell function is not clearly understood. Our laboratory has shown that chronic exposure of rats to nicotine inhibits the antibody-forming cell response, impairs the antigen-mediated signaling in T cells, and induces T cell anergy. To determine the mechanism of cigarette smoke-induced immunosuppression and to compare it with chronic nicotine exposure, rats were exposed to diluted, mainstream cigarette smoke for up to 30 months or to nicotine (1 mg/kg b.wt./24 h) via miniosmotic pumps for 4 weeks, and evaluated for immunological function in vivo and in vitro. This article presents evidence suggesting that T cells from long-term cigarette smoke-exposed rats exhibit decreased antigen-mediated proliferation and constitutive activation of protein tyrosine kinase and phospholipase C-gamma1 activities. Moreover, spleen cells from smoke-exposed and nicotine-treated animals have depleted inositol-1, 4,5-trisphosphate-sensitive Ca(2+) stores and a decreased ability to raise intracellular Ca(2+) levels in response to T cell antigen receptor ligation. These results suggest that chronic smoking causes T cell anergy by impairing the antigen receptor-mediated signal transduction pathways and depleting the inositol-1,4, 5-trisphosphate-sensitive Ca(2+) stores. Moreover, nicotine may account for or contribute to the immunosuppressive properties of cigarette smoke.


Assuntos
Cálcio/metabolismo , Imunidade/efeitos dos fármacos , Inositol 1,4,5-Trifosfato/fisiologia , Nicotiana , Plantas Tóxicas , Transdução de Sinais/imunologia , Fumaça/efeitos adversos , Linfócitos T/imunologia , Animais , Células Produtoras de Anticorpos/efeitos dos fármacos , Antígenos/imunologia , Cotinina/sangue , Ativação Enzimática/efeitos dos fármacos , Feminino , Nível de Saúde , Isoenzimas/metabolismo , Nicotina/farmacologia , Agonistas Nicotínicos/farmacologia , Fosfolipase C gama , Proteínas Tirosina Quinases/metabolismo , Ratos , Ratos Endogâmicos F344 , Complexo Receptor-CD3 de Antígeno de Linfócitos T/efeitos dos fármacos , Complexo Receptor-CD3 de Antígeno de Linfócitos T/imunologia , Transdução de Sinais/efeitos dos fármacos , Baço/citologia , Baço/efeitos dos fármacos , Baço/imunologia , Linfócitos T/efeitos dos fármacos , Fosfolipases Tipo C/metabolismo
14.
FEMS Microbiol Lett ; 183(2): 331-6, 2000 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-10675606

RESUMO

In vitro excystation is often used as a measure of viability of encysted protozoan parasites. Parasites that do not excyst in vitro are assumed to be non-viable and non-infectious, whereas those that do excyst are assumed viable. To test the validity of these assumptions, Cryptosporidium parvum oocysts were excysted in vitro using two different excystation protocols, and the non-excysted intact oocysts were isolated using flow cytometry. Non-excysted sorted oocysts readily infected neonatal CD-1 mice. Increasing the duration of the excystation assays from 1 h to 3 h resulted in a higher percent of excysted oocysts, but the remaining non-excysted parasites were still capable of infecting neonatal CD-1 mice. Our results suggest that in vitro excystation is not an accurate measure of the viability or infectious potential of C. parvum oocysts.


Assuntos
Cryptosporidium parvum/patogenicidade , Animais , Animais Recém-Nascidos , Citometria de Fluxo , Masculino , Camundongos
15.
Appl Environ Microbiol ; 66(1): 406-12, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10618255

RESUMO

Cryptosporidium parvum oocysts were stained with the fluorogenic dyes SYTO-9 and SYTO-59 and sorted by flow cytometry in order to determine whether the fluorescent staining intensity correlated with the ability of oocysts to infect neonatal CD-1 mice. Oocysts that did not fluoresce or that displayed weak fluorescent intensity when stained with SYTO-9 or SYTO-59 readily established infections in mice, whereas those oocysts that fluoresced brightly did not. Although fluorescent staining profiles varied among different batches of oocysts, a relative cutoff in fluorescent staining intensity that correlated with animal infectivity was observed for all batches.


Assuntos
Criptosporidiose/parasitologia , Cryptosporidium parvum/crescimento & desenvolvimento , Cryptosporidium parvum/patogenicidade , Ácidos Nucleicos/análise , Compostos Orgânicos , Animais , Corantes/metabolismo , Cryptosporidium parvum/genética , Camundongos , Microscopia Confocal , Coloração e Rotulagem , Abastecimento de Água
16.
Commun Dis Public Health ; 2(4): 291-2, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10598389

RESUMO

A survey of 400 patients discharged from medical wards found that 161 (40%) had risk factors for severe pneumococcal infection, but that only half of these had received pneumococcal vaccine. Improved vaccine uptake in high risk patients could be achieved by universal vaccination of people aged over 65 years.


Assuntos
Vacinas Bacterianas , Infecções Pneumocócicas/prevenção & controle , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Inglaterra , Pesquisas sobre Atenção à Saúde , Hospitais Gerais , Humanos , Vacinas contra Influenza , Pessoa de Meia-Idade , Alta do Paciente , Sistema de Registros , Fatores de Risco , Inquéritos e Questionários , Vacinação/estatística & dados numéricos
17.
Toxicol Appl Pharmacol ; 161(2): 171-9, 1999 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-10581211

RESUMO

Cigarette smoking is associated with respiratory diseases that may be caused by injury to specific pulmonary cells. The injury may manifest itself as site-specific enhanced cellular replication. In this study, rats were exposed either to mainstream cigarette smoke (CS; 250 mg total particulate matter/m(3)) or to filtered air (FA) for 6 h/day, 5 days/week, for 2 weeks. In one group, cells in S-phase were labeled over 7 days by bromodeoxyuridine (BrdU) released from implanted osmotic pumps (pump labeled), while another group received BrdU by injection 2 h prior to necropsy (pulse labeled). Morphometry showed that the type II epithelial BrdU labeling index (LI) was significantly elevated in the CS-exposed animals of both labeling groups. The axial airway and terminal bronchiolar LIs were enhanced by CS only in the pump-labeled group. In a third group (pulse labeled), 2 weeks of recovery following exposure to CS allowed a normalization in the type II LI. In the pump-labeled rats, the CS-induced elevation of the type II LI was greater than the LI elevation in conducting airways, suggesting that the parenchyma may have been injured more than the conducting airways. The terminal bronchiolar LI in the pump-labeled group, regardless of exposure, was significantly greater than the axial airway LI. Pump labeling, in contrast to pulse labeling, could therefore discern differences among replication rates of conducting airway epithelium in different regions of the lung. Mucosubstance (MS) within the axial airway epithelium was quantified by morphometry. The CS exposure did not increase the total number of MS-containing cells or the total number of axial airway epithelial cells, but there was a phenotype change in the MS cells. Neutral MS cells (periodic acid-Schiff-positive) were significantly decreased, while acid MS cells (alcian blue-positive) were slightly increased by CS exposure. Either cell replication and differentiation or differentiation alone may have changed the phenotype in the MS cell population.


Assuntos
Nicotiana , Plantas Tóxicas , Mucosa Respiratória/efeitos dos fármacos , Fumaça/efeitos adversos , Administração por Inalação , Animais , Bromodesoxiuridina , Divisão Celular/efeitos dos fármacos , Feminino , Masculino , Muco/química , Fenótipo , Ratos , Ratos Endogâmicos F344 , Mucosa Respiratória/química , Mucosa Respiratória/citologia
19.
Toxicol Sci ; 51(2): 289-99, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10543031

RESUMO

Cigarette smoke (CS) causes pulmonary emphysema in humans, but results of previous studies on CS-exposed laboratory animals have been equivocal and have not clearly demonstrated progression of the disease. In this study, morphometry and histopathology were used to assess emphysema in the lungs of B6C3F1 mice and Fischer-344 rats. The animals were exposed, whole-body, to CS at a concentration of 250 mg total particulate matter/m3 for 6 h/day, 5 days/week, for either 7 or 13 months. Morphometry included measurements of parenchymal air space enlargement (alveolar septa mean linear intercept [Lm], volume density of alveolar air space [VVair]), and tissue loss (volume density of alveolar septa [VVspt]). In addition, centriacinar intra-alveolar inflammatory cells were counted to assess species differences in the type of inflammatory response associated with CS exposure. In mice, many of the morphometric parameters indicating emphysema differed significantly between CS-exposed and control animals. In CS-exposed rats, only some of the parameters differed significantly from control values. The Lm in both CS-exposed mice and rats was increased at 7 and 13 months, indicating an enlargement of parenchymal air spaces, but the VVair was increased significantly only in CS-exposed mice. The VVspt was decreased at both time points in mice, but not in rats, indicating damage to the structural integrity of parenchyma. Morphologic evidence of tissue destruction in the mice included alveoli that were irregular in size and shape and alveoli with multiple foci of septal discontinuities and isolated septal fragments. Morphometric differences in the mice at 13 months were greater than at 7 months, suggesting a progression of the disease. Inflammatory lesions within the lungs of mice contained significantly more neutrophils than those lesions in rats. These results suggest that B6C3F1 mice are more susceptible than F344-rats to the induction of emphysema by this CS exposure regimen and that in mice the emphysema may be progressive. Furthermore, the type of inflammatory response may be a determining factor for species differences in susceptibility to emphysema induction by CS exposure.


Assuntos
Nicotiana , Plantas Tóxicas , Enfisema Pulmonar/etiologia , Fumaça/efeitos adversos , Animais , Cruzamentos Genéticos , Modelos Animais de Doenças , Suscetibilidade a Doenças , Feminino , Pulmão/patologia , Macrófagos/patologia , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Neutrófilos/patologia , Enfisema Pulmonar/patologia , Ratos , Ratos Endogâmicos F344 , Especificidade da Espécie , Aumento de Peso
20.
Environ Res ; 80(1): 9-17, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9931222

RESUMO

BACKGROUND: Epidemiological data indicate that in females cigarette smoking exerts antiestrogenic effects that manifest clinically in an increased incidence of osteoporosis, earlier menopause, increased spot bleeding, and decreased risk of endometrial cancer for female smokers. The molecular mechanism of this effect is unclear; however, decreased serum estrogen levels in female smokers have been correlated with increased concentrations of the metabolite 2-hydroxyestrogen in females who smoke. Induction of estrogen metabolizing enzymes, CYP1A1 and 1A2, is one mechanism by which increased 2-hydroxyestrogen concentrations may occur. It has also been suggested that the estrogen receptor (ER) may contribute to this anti-estrogenic effect by binding to antagonist(s) in cigarette smoke. METHODS: Gel retardation analysis was employed to determine if diluted mainstream cigarette smoke condensates (DMCSCs) could activate the aryl hydrocarbon receptor (AhR). AhR-regulated ethoxyresorufin-O-deethylase (EROD) activity and dioxin response element (DRE)-mediated luciferase induction were assessed in Hepa1c1c7 mouse hepatoma cells. A competitive ligand binding assay was utilized to determine if DMCSCs could bind to the ER. ER-dependent luciferase activity was assessed in MCF-7 cells. RESULTS: In gel retardation assays, DMCSCs induced a protein-DNA complex when incubated with a radiolabeled wild-type DRE oligonucleotide. The complex was effectively competed by excess unlabeled DRE but not by excess unlabeled mutant DRE. In Hepa1c1c7 mouse hepatoma cells transiently transfected with a DRE-regulated luciferase reporter gene, pGudluc1.1, treatment with DMCSCs resulted in a 23- and 25-fold increase in luciferase activity (P<0.01) and an 8.5- and 10.5-fold (P<0.01) induction in EROD activity, respectively. DMCSCs completely displaced bound tritiated E2 from the ER in a dose-dependent manner and induced ER-regulated luciferase activity significantly 6-fold (P<0.01), representing 86% of the maximal induction observed with E2. CONCLUSIONS: DMCSCs can bind to and transcriptionally activate the AhR and ER nuclear receptors and cause induction of DRE- and ER-regulated genes. Further study is required to identify the specific compound(s) responsible for these activities.


Assuntos
Poluição do Ar em Ambientes Fechados/efeitos adversos , Receptores de Hidrocarboneto Arílico/agonistas , Receptores de Estrogênio/agonistas , Fumar/efeitos adversos , Poluição por Fumaça de Tabaco/efeitos adversos , Transcrição Gênica , Animais , Neoplasias da Mama/metabolismo , Carcinoma Hepatocelular/metabolismo , Citocromo P-450 CYP1A1/biossíntese , Indução Enzimática , Feminino , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Fígado/metabolismo , Neoplasias Hepáticas Experimentais/metabolismo , Luciferases/biossíntese , Luciferases/genética , Camundongos , Ratos , Ratos Sprague-Dawley , Receptores de Hidrocarboneto Arílico/fisiologia , Receptores de Estrogênio/fisiologia , Células Tumorais Cultivadas , Útero/metabolismo
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