Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 16 de 16
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Aust Dent J ; 55(1): 79-85, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20415916

RESUMO

BACKGROUND: The biological examination of pulp injury, repair events and response of dental pulp stem cells to dental restorative materials is important to accomplish restorative treatment, especially to commonly used dental materials in paediatric dentistry, such as glass ionomer cement (GIC) and calcium hydroxide (Ca(OH)(2)) lining cement. METHODS: Healthy patients aged between 9 to 11 years with carious primary molars without pulp exposure were selected and divided into two groups: Group 1 (teeth restored with GIC) and Group 2 (teeth lined using Ca(OH)(2) and restored with GIC). The proliferative activity of stem cells of teeth between these two groups was compared using colourimetric cell proliferation reagent, alamarBlue. Immunocytochemistry and flow cytometry confirmation were performed using mesenchymal stem cell markers, CD105 and CD166. RESULTS: The proliferative activity using alamarBlue assay showed that cells derived from the remaining dental pulp of exfoliated deciduous teeth were positive for CD105 and CD166 and exhibited no difference between the two groups. CONCLUSIONS: It can be concluded that the use of Ca(OH)(2) or GIC as a lining material in indirect pulp capping procedures has the same effect on cells derived from the remaining dental pulp of exfoliated deciduous teeth which have responded favourably to the restorative treatments.


Assuntos
Hidróxido de Cálcio/uso terapêutico , Forramento da Cavidade Dentária , Polpa Dentária/efeitos dos fármacos , Restauração Dentária Permanente/métodos , Cimentos de Ionômeros de Vidro , Células-Tronco/efeitos dos fármacos , Antígenos CD/análise , Biomarcadores/análise , Moléculas de Adesão Celular Neuronais/análise , Proliferação de Células/efeitos dos fármacos , Criança , Colorimetria , Cárie Dentária/terapia , Polpa Dentária/citologia , Endoglina , Proteínas Fetais/análise , Citometria de Fluxo , Seguimentos , Humanos , Imuno-Histoquímica , Indicadores e Reagentes , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/patologia , Dente Molar/patologia , Oxazinas , Receptores de Superfície Celular/análise , Dente Decíduo/patologia , Xantenos
2.
Neurourol Urodyn ; 19(2): 195-206; discussion 206-8, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10679836

RESUMO

Partial obstruction of the rat bladder outlet initiates a multi-step process during which the bladder progressively loses its functional ability. The first step in this progression is bladder hypertrophy; the organ dramatically increases in size and weight to compensate for the effects of obstruction. Unoperated female rats, age-matched, sham-obstructed rats, and rats that received a partial bladder outlet obstruction were studied. During the first 24 hours after partial bladder outlet obstruction, relative bladder blood flow was measured using a fluorescent microsphere infusion technique and laser Doppler imaging. Nitric oxide synthase (NOS) activities of control and obstructed rat bladder tissues were determined using an enzymatic assay that measures the conversion of (3)H-L-arginine to (3)H-L-citrulline. Using the microsphere infusion technique, a significant increase in blood flow to the obstructed rat bladder was observed during the first 24 hours after partial bladder outlet obstruction. Relative bladder blood flow increased approximately sixfold at 4 and 6 hours post-obstruction and remained elevated through 24 hours of obstruction. Sham operations (evaluated after 6 hours after surgery) resulted in a minor increase in blood flow that did not reach statistical significance. Relative blood flow to the spleen, measured in the same rats, was not significantly changed. Laser Doppler measurements also identified a significant increase in rat bladder blood flow after outlet obstruction and showed that increased blood flow could be detected as early as 1 hour post-obstruction. Interestingly, despite the significant differences in bladder blood flow between control and early post-obstructed rat bladders, NOS activities of control and obstructed rat bladders were comparable. The increase in bladder blood flow precedes the urothelial, fibroblast and smooth muscle cell hyperplasia, and the smooth muscle hypertrophy that occurs after obstruction. We propose that, in response to surgical induction of partial outlet obstruction, acute up-regulation of bladder blood flow may be an initiating factor for subsequent bladder cell proliferation and smooth muscle hypertrophy. Neurourol. Urodynam. 19:195-208, 2000.


Assuntos
Fluxo Sanguíneo Regional , Obstrução do Colo da Bexiga Urinária/fisiopatologia , Bexiga Urinária/parasitologia , Animais , Feminino , Fibroblastos/patologia , Fluorometria , Hiperplasia , Hipertrofia , Fluxometria por Laser-Doppler , Microesferas , Músculo Liso/patologia , Óxido Nítrico Sintase/análise , Ratos , Ratos Sprague-Dawley , Bexiga Urinária/enzimologia , Bexiga Urinária/patologia , Obstrução do Colo da Bexiga Urinária/patologia , Urotélio/patologia
3.
Urology ; 53(2): 440-5, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9933075

RESUMO

OBJECTIVES: Recent studies have shown that Exisulind, a sulfone metabolite of the nonsteroidal anti-inflammatory drug (NSAID) sulindac, has inhibitory activity in vitro with cultured human prostate cancer cells. To determine whether this effect might be pharmacologically relevant in vivo, we tested whether Exisulind therapy could suppress the growth of human prostate cancer cells in a nude mouse xenograft model. METHODS: Thirty athymic nude mice were injected subcutaneously in the flank with 1 x 10(7) LNCaP human prostate tumor cells. All mice received a control diet for 21 days. One group of mice was continued on this control diet for an additional 4 weeks, a second group was switched to a diet supplemented with 0.05% Exisulind (40% of maximal tolerated dose [MTD]), and a third group was switched to a diet supplemented with 0.1% Exisulind (80% MTD) for the additional 4 weeks. Tumor growth was measured through the 4-week test period, and subsequently tissue sections from the various groups were tested for apoptotic and dividing cells by quantified use of the TUNEL assay and a bromodeoxyuridine (BrdU) incorporation immunoassay. RESULTS: Tumors grew by 158%, 24%, and 18% for the control and 0.05% and 0.1% Exisulind groups, respectively (P = 0.02) during the 4-week test period. Immunohistochemical studies on excised tumors showed an increased number of apoptotic bodies in the treated groups versus the control group (P<0.0001) but no change in the number of BrdU positive cells. CONCLUSIONS: This is the first study to show a direct in vivo effect of an NSAID-derived drug, lacking cyclooxygenase inhibitory activity, in a xenograft model of prostate cancer. Clinical studies to evaluate the effects of Exisulind against prostate cancer in humans are warranted.


Assuntos
Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Neoplasias da Próstata/tratamento farmacológico , Sulindaco/análogos & derivados , Animais , Divisão Celular , Humanos , Masculino , Camundongos , Camundongos Nus , Transplante de Neoplasias , Neoplasias da Próstata/patologia , Sulindaco/uso terapêutico
4.
J Urol ; 161(2): 460-2, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9915426

RESUMO

PURPOSE: Recent reports suggest declining sperm counts in the United States. These reports did not include all available data and did not account for geographic variations noted in prior studies. We examined all available data on U.S. sperm counts and evaluated whether geographic variations account for the decline suggested. MATERIALS AND METHODS: We reviewed all 29 U.S. studies from 1938 to 1996 reporting manually counted semen analyses of 9,612 fertile or presumably fertile men. We determined mean sperm concentrations by geographic location with weighted analysis of variance, and assessed any changes with time by linear regression analysis. RESULTS: Mean sperm concentrations from New York were significantly higher than from all other U.S. cities (98.6 versus 71.6 x 10(6) sperm per cc, respectively, p = 0.006). There has been no statistically significant change with time for mean sperm concentrations reported from New York (p = 0.49) or from U.S. cities other than New York (p = 0.62). Analysis without separating by location revealed a decline (p = 0.047). CONCLUSIONS: Sperm concentrations are highest in New York compared to other U.S. cities. When accounting for this geographic difference and examining all available data, there appears to be no significant change in sperm counts in the U.S. during the last 60 years. Further studies addressing the causes of geographic variations are needed.


Assuntos
Contagem de Espermatozoides , Humanos , Masculino , Estados Unidos
5.
Urology ; 52(6): 1000-3, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9836544

RESUMO

OBJECTIVES: To determine the pattern of disease recurrence after radical nephrectomy in patients with node-positive renal cell carcinoma (RCC) in order to design a schedule for subsequent radiologic evaluation. METHODS: We reviewed the postoperative radiologic studies of 45 patients with T1-3a,b,c or T4N+M0 RCC enrolled in a prospective trial of adjuvant autolymphocyte therapy (ALT) after radical nephrectomy for node-positive disease. Chest radiograph and abdominal computed tomography (CT) were performed quarterly, and bone scan and head CT were performed every 6 months until disease recurrence, or earlier if clinically indicated. Time from surgery to recurrence and sites of recurrence were analyzed. RESULTS: Twenty-nine patients (64%) had disease progression, with a mean time to progression of 14.9 months. Mean follow-up of patients without progression was 39 months. The sites of recurrence were retroperitoneal lymph nodes (n=14), lung (n=11), liver (n=5), bone (n=5), mediastinal lymph nodes (n=4), renal fossa (n=3), pelvis (n=2), brain (n=2), contralateral kidney (n=1), retrocecum (n=1), and skin (n=1). Fourteen patients had recurrence at more than one site. Of the patients whose disease progressed, 59% did so by 12 months, 83% by 24 months, and 93% by 36 months. Mean time to progression in the ALT group was delayed compared with the observation group, but the sites of disease recurrence were not different between the two groups. Abdominal CT alone detected recurrent lesions in 79% of patients with progression, and the combination of abdominal CT and chest radiograph detected lesions in 100% of patients with progression. CONCLUSIONS: Abdominal CT with chest radiograph detects recurrence in all patients with T1-3a,b,c or T4N+M0 RCC whose disease progresses, and more than 90% of recurrences occur within the first 3 years after surgery. We recommend abdominal CT and chest radiograph every 6 months for at least 3 years and yearly thereafter in this high-risk group of patients.


Assuntos
Carcinoma de Células Renais/diagnóstico por imagem , Carcinoma de Células Renais/cirurgia , Neoplasias Renais/diagnóstico por imagem , Neoplasias Renais/cirurgia , Recidiva Local de Neoplasia/diagnóstico por imagem , Nefrectomia , Carcinoma de Células Renais/patologia , Progressão da Doença , Feminino , Seguimentos , Humanos , Neoplasias Renais/patologia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/epidemiologia , Estadiamento de Neoplasias , Estudos Prospectivos , Radiografia
6.
Obstet Gynecol ; 92(4 Pt 1): 619-21, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9764639

RESUMO

OBJECTIVE: To compare duration of surgery, length of hospital stay, complications, and short-term cure rate of extraperitoneal laparoscopic colposuspension with that of Burch colposuspension. METHODS: We retrospectively reviewed 157 consecutive cases of extraperitoneal laparoscopic (n=70) or Burch colposuspension (n=87) performed between January 1, 1995, and June 30, 1997. Cure rate was assessed by history, physical examination, and questionnaire. Patients not requiring the use of pads were considered continent. Cure rates were compared in the entire group, whereas complications, duration of surgery, and length of stay were compared only in subgroups undergoing colposuspension alone. Results were analyzed statistically. RESULTS: The mean times to follow-up were 12.9 months (laparoscopic group) and 16.3 months (Burch group). At last follow-up, 64 of 70 (91.4%) of the laparoscopic and 80 of 87 (92%) of the Burch colposuspension group were continent. In patients who underwent colposuspension alone, results were as follows for those who underwent laparoscopic (19) and Burch (21) procedures, respectively: average duration of surgery, 49.2 compared with 62.6 minutes (P < .03); average hospital stay, 14 hours compared with 2.7 days (P < .001); average postoperative disability period, 1.6 weeks compared with 4.7 weeks (P < .001); incidence of complications, 15.8% compared with 33.3% (P=.170). CONCLUSION: Extraperitoneal laparoscopic colposuspension, compared with Burch colposuspension, resulted in similar short-term cure rates and complications, shorter duration of surgery, hospital stay, and convalescence. It is a feasible option in treatment of stress urinary incontinence when laparotomy is not required.


Assuntos
Laparoscopia , Tempo de Internação , Incontinência Urinária por Estresse/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Tempo , Vagina
7.
J Am Assoc Gynecol Laparosc ; 5(3): 247-52, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9668145

RESUMO

STUDY OBJECTIVE: To evaluate endoscopic colposuspension with extraperitoneal and direct entry into the space of Retzius. DESIGN: Prospective case series (Canadian Task Force classification II-1). SETTING: University of Texas Health Science Center and unaffiliated private practice, San Antonio, Texas. PATIENTS: Seventy women with genuine urinary stress incontinence. INTERVENTION: The space of Retzius was entered directly through a 1.5-cm incision about 2 inches above the symphysis pubis. Three cannulas were inserted at the suprapubic area to access extraperitoneum. Permanent sutures were introduced into the space of Retzius, and with a 5-mm needle holder a double bite was taken into paravaginal fascia on either side. Cooper's ligaments were identified and the needle was passed through the ligaments medial to obturator vessels. To secure sutures, we used a simple surgical knot followed by square knots with either extracorporeal or intracorporeal method. Paravaginal fascia was pulled toward Cooper's ligaments to produce a zero-degree Q-Tip angle in the urethra. MEASUREMENTS AND MAIN RESULTS: Of 70 women, 64 (91.4%) were clinically continent after surgery. Average duration of follow-up so far is 15.9 months. Twenty-nine patients were managed as short-stay admissions, and average length of hospital stay for women who had only colposuspension was 14 hours. Two cases were converted to laparotomy, and two patients had endoscopic repair of bladder perforation. CONCLUSION: Extraperitoneal laparoscopic Burch colposuspension produced direct access to the space of Retzius with satisfactory visualization and acceptable outcome. It may be performed as a short-stay procedure in selected patients.


Assuntos
Laparoscopia/métodos , Bexiga Urinária/cirurgia , Incontinência Urinária por Estresse/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Técnicas de Sutura , Resultado do Tratamento
9.
J Urol ; 159(4): 1276-80, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9507852

RESUMO

PURPOSE: We determine the incidence of urinary incontinence after radical prostatectomy and the factors that may influence this incidence. MATERIALS AND METHODS: A total of 615 men who underwent radical retropubic prostatectomy performed by 1 of us (C. A. O. or M. C. B.) at our center between 1988 and 1996 were mailed a questionnaire regarding preoperative and postoperative voiding habits. Data collected included preoperative and postoperative continence status, interval to postoperative continence status, associated urinary symptoms, willingness to undergo radical prostatectomy again if given the chance and additional postoperative procedures. Patient age, date of surgery and duration of followup were also noted. RESULTS: Of the 615 patients 480 (78.2%), a mean of 62.6 years old, responded to the questionnaire. Mean followup was 3.3 years (range 1 to 8.8). Continence was defined as no regular use of pads. Of the respondents 91.8% were considered continent, 92% had achieved final continence status by 6 months postoperatively, 10.6% required 1 or more additional procedures related to urinary control and 90% would undergo surgery again if given the chance. Of the patients considered incontinent postoperatively 44% had associated urgency. Age, year of surgery and preoperative urinary leakage or post-void dribbling had no significant impact on postoperative continence status. CONCLUSIONS: Using an anonymous self-administered questionnaire we found an 8.2% incontinence rate after radical prostatectomy. This rate was similar to that in large, single institutional studies in which physician interview was used to elicit responses but significantly less than that in a national sample of Medicare patients also given a self-administered questionnaire. With minimal potential for adverse consequences in the hands of experienced surgeons, radical prostatectomy remains well tolerated with excellent patient satisfaction.


Assuntos
Prostatectomia/efeitos adversos , Incontinência Urinária/epidemiologia , Idoso , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/cirurgia , Inquéritos e Questionários , Incontinência Urinária/etiologia
10.
Urology ; 50(5): 789-91, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9372896

RESUMO

Sweat gland carcinomas are rare tumors which have not previously been reported as arising from the scrotum. We present the first known case of primary eccrine sweat gland carcinoma of the scrotum in association with extramammary Paget's disease (EPD) and review the presentation and management of these tumors. Sweat gland carcinomas frequently coexist with EPD and this association provides insight into the histogenesis of EPD, which is presently unknown. Sweat gland carcinoma should be included in the differential diagnosis of cutaneous scrotal tumors and carefully ruled out pathologically if the diagnosis of EPD alone is made.


Assuntos
Adenocarcinoma/patologia , Neoplasias dos Genitais Masculinos/patologia , Neoplasias Primárias Múltiplas/patologia , Doença de Paget Extramamária/patologia , Escroto , Idoso , Humanos , Masculino
12.
Cancer Res ; 51(16): 4388-94, 1991 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-1907884

RESUMO

A canal was surgically created in the lower lip of male Sprague-Dawley rats and used as a reservoir for moist snuff. A total of 230 animals were randomized into six groups, five containing 40 rats and one containing 30 rats. After 2 wk of recuperation, the animals were treated as follows. Group I was initiated with 7,12-dimethylbenz(a)anthracene 3 times/wk for 4 wk followed by cotton pellet administration. Group II was initiated with 7,12-dimethylbenz(a)anthracene for 4 wk followed by snuff twice a day, 5 days/wk. Group III received snuff twice a day, 5 days/wk. Groups IV and V were initiated with 4-nitroquinoline N-oxide 3 days/wk for 4 wk. Thereafter Group IV received a cotton pellet, and Group V rats were treated with snuff twice a day, 5 days/wk. Group VI received a cotton pellet once a day, 5 days/wk. Treatment of all groups continued for a maximum of 104 wk. Group V rats had a significantly lower mean survival time than did the other groups because of the development of lip sarcomas in 66% of the rats as compared with 23% in Group II and 26% in Group III. One rat in each of Groups IV and VI developed lip sarcomas. The incidence of sarcomas in Group V as compared with the other groups is statistically significant (P less than 0.05 to 0.001). Spindle cell proliferation, a possible precursor lesion of lip sarcoma, was found in five rats of Group II, seven of Group III, and four of Group V. These results show that snuff has strong promoting capability with regard to the development of lip sarcomas after 4-nitroquinoline N-oxide initiation, but not after 7,12-dimethylbenz(a)anthracene initiation. Snuff by itself caused three squamous carcinomas of the palate, two squamous cell papillomas of the lip, and ten lip sarcomas (in 38 rats as compared with one lip sarcoma in 30 control rats), showing snuff to be carcinogenic for the lip and oral cavity.


Assuntos
4-Nitroquinolina-1-Óxido/toxicidade , 9,10-Dimetil-1,2-benzantraceno/toxicidade , Carcinógenos , Neoplasias Gastrointestinais/induzido quimicamente , Neoplasias de Cabeça e Pescoço/induzido quimicamente , Neoplasias Labiais/induzido quimicamente , Plantas Tóxicas , Tabaco sem Fumaça/toxicidade , Animais , Peso Corporal/efeitos dos fármacos , Sinergismo Farmacológico , Neoplasias Gastrointestinais/patologia , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias Labiais/patologia , Masculino , Nitrosaminas/análise , Ratos , Ratos Endogâmicos
13.
IARC Sci Publ ; (105): 507-9, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1906838

RESUMO

In an experiment to evaluate the carcinogenicity and promoting capacity of snuff, a reservoir was created in the lower lip of male Sprague-Dawley rats. Groups of 30 rats were treated with snuff only (twice a day on five days a week), propylene glycol (solvent) three times weekly for four weeks, painting of the hard palate with 4-nitroquinoline-N-oxide (4-NQO) three times weekly for four weeks followed by snuff, 4-NQO only for four weeks, or cotton pellets only (twice a day on five days a week). The experiment was continued up to 108 weeks. High levels of tobacco-specific nitrosamines were found in the snuff (a commercial US brand). Rats treated with snuff only, 4-NQO followed by snuff and 4-NQO only had a significantly higher number of squamous-cell tumours and hyperplastic squamous lesions of the lip, oral and nasal cavity and forestomach than solvent or untreated controls. The total number of neoplasms was significantly higher in rats treated with snuff only and with 4-NQO followed by snuff in comparison to the other groups. Thus, snuff and 4-NQO by themselves can induce benign and malignant tumours. Snuff appears to have a general tumorigenic effect but lacked promoting ability after initiation with 4-NQO.


Assuntos
4-Nitroquinolina-1-Óxido/toxicidade , Neoplasias Experimentais/etiologia , Plantas Tóxicas , Tabaco sem Fumaça , Animais , Masculino , Ratos , Ratos Endogâmicos
14.
Cancer Res ; 49(11): 3063-9, 1989 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-2497972

RESUMO

A canal in the lower lip to function as a reservoir for snuff was surgically created in 150 male Sprague-Dawley rats. The animals were randomized into five groups of 30 each: Group I received snuff twice a day, 5 days a wk; Group II was painted with propylene glycol (solvent control) on the hard palate 3 times a wk during 4 wk; Group III underwent painting on the hard palate with 4-nitroquinoline N-oxide (4-NQO) dissolved in propylene glycol, 3 times a wk for 4 wk; Group IV received 4-NQO as in Group III followed by snuff application as in Group I; and Group V received a cotton pellet dipped in saline twice a day, 5 days a wk. Treatment continued for up to 108 wk. There was no significant difference in mean survival time between the groups. Squamous cell tumors of the lip, oral and nasal cavities, esophagus, and forestomach were seen only in Groups I, III, and IV. Nine tumors of these organs were found in Group I (six carcinomas and three papillomas), nine in Group III (seven carcinomas and two papillomas), and ten in Group IV (eight carcinomas and two papillomas). The difference between each of these groups and the control groups (II and V) with regard to tumor incidence is statistically significant (P less than 0.05). In Group I, four oral cavity or lip carcinomas were found in 29 rats, a significant difference in relation to control rats (P less than 0.05). In addition, hyperplastic lesions of the lip, palate, and forestomach were significantly more common in Groups I and IV compared with Groups II, III, and V. The study has shown that snuff and 4-NQO by themselves have the potential to induce malignant tumors. Initiation with 4-NQO followed by snuff did not significantly enhance tumor formation.


Assuntos
Carcinoma de Células Escamosas/etiologia , Neoplasias Bucais/etiologia , Nicotiana , Neoplasias Nasais/etiologia , Plantas Tóxicas , Tabaco sem Fumaça , 4-Nitroquinolina-1-Óxido , Animais , Peso Corporal , Carcinoma de Células Escamosas/patologia , Neoplasias Esofágicas/etiologia , Neoplasias Esofágicas/patologia , Neoplasias Labiais/etiologia , Neoplasias Labiais/patologia , Masculino , Neoplasias Bucais/patologia , Neoplasias Nasais/patologia , Distribuição Aleatória , Ratos , Ratos Endogâmicos , Neoplasias Gástricas/etiologia , Neoplasias Gástricas/patologia , Neoplasias da Língua/etiologia , Neoplasias da Língua/patologia
15.
Carcinogenesis ; 10(1): 105-11, 1989 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2910518

RESUMO

Abuse of combination analgesics containing phenacetin, antipyrine (phenazone) and caffeine have been associated with urinary tract tumors. Phenacetin and antipyrine have been shown to be promoters of urinary tract carcinogenesis and antipyrine is also a weak urinary tract carcinogen. Acetaminophen, the main metabolite of phenacetin, is one of the most commonly used analgesics in the USA. In the present study, the dose-related effect on the cell proliferation of the urothelium was evaluated in male Sprague-Dawley rats by autoradiography. Nine groups of twenty, 6-week old rats were treated with 0.5%, 1.0% or 1.5% of acetaminophen, antipyrine or phenacetin in the diet. A tenth group of rats received control diet without added chemicals. Ten rats from each group were killed after each of 6 and 12 weeks of feeding. There was a dose-related increase in the labeling index in the urothelium of the bladder and kidney, particularly after 6 weeks of drug administration. In particular, the 1.0% and 1.5% dose levels of antipyrine and phenacetin showed a marked proliferative effect on the urothelium. In the bladder after 6 weeks, the labeling indices were significantly increased. After 12 weeks, although numerically increased, the indices were not statistically significant. In the renal pelvic urothelium the labeling index was significantly increased in antipyrine and phenacetin treated rats at doses of 1.0% and 1.5%. After 12 weeks the majority of rats treated with 1.5% antipyrine and phenacetin had labeling indices greater than or equal to 2-fold than the control rats both in the kidney and bladder. The increased labeling indices were associated with urothelial hyperplasia, in particular after 6 weeks. In the rats treated with antipyrine there were significant degenerative changes in the urothelial cells expressed as marked vacuolization. The vacuolization is considered to be a toxic effect and the beginning of cell death. Thus cell death with regeneration may be responsible for the increased labeling index in the antipyrine groups. High doses of antipyrine were also associated with renal papillary necrosis in 50% of the rats.


Assuntos
Acetaminofen/farmacologia , Antipirina/farmacologia , Fenacetina/farmacologia , Neoplasias Urológicas/induzido quimicamente , Animais , Divisão Celular/efeitos dos fármacos , Células Epiteliais , Epitélio/efeitos dos fármacos , Hiperplasia , Pelve Renal/patologia , Masculino , Ratos , Ratos Endogâmicos , Bexiga Urinária/efeitos dos fármacos , Bexiga Urinária/patologia , Neoplasias Urológicas/patologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...