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1.
Int J Tuberc Lung Dis ; 18(9): 1074-83, 2014 Sep.
Article in English | MEDLINE | ID: mdl-25189555

ABSTRACT

SETTING: Pediatric multidrug-resistant tuberculosis (MDR-TB) is complicated by difficult diagnosis, complex treatment, and high mortality. In South Africa, these challenges are amplified by human immunodeficiency virus (HIV) co-infection; however, evidence on treatment outcomes among co-infected children is limited. OBJECTIVE: Using conventional and new pediatric definitions, to describe treatment outcomes and identify risk factors for unfavorable outcome and mortality in children aged <15 years with MDR-TB or extensively drug-resistant TB (XDR-TB) in KwaZulu-Natal, South Africa. DESIGN: Retrospective cohort study in a regional TB referral hospital. RESULTS: From January 2009 to June 2010, 84 children (median age 8 years, IQR 4-12) with MDR-TB (n = 78) or XDR-TB (n = 6) initiated treatment. Sixty-four (77%) were HIV-positive and 62 (97%) received antiretroviral therapy. Sixty-six (79%) achieved favorable treatment outcomes. Overall mortality was 11% (n = 9) at 18 months after initiation of treatment. Malnutrition (aOR 27.4, 95%CI 2.7-278.7) and severe radiographic findings (aOR 4.68, 95%CI 1.01-21.9) were associated with unfavorable outcome. New pediatric outcome definitions increased the proportion classified as cured. CONCLUSION: It is possible to successfully treat pediatric MDR-TB-HIV even in resource-poor settings. Malnutrition is a marker for severe TB-HIV disease, and is a potential target for future interventions in these patients.


Subject(s)
Child Nutrition Disorders/mortality , Coinfection , HIV Infections/mortality , Malnutrition/mortality , Tuberculosis, Multidrug-Resistant/mortality , Age Factors , Anti-HIV Agents/therapeutic use , Antitubercular Agents/therapeutic use , Child , Child Nutrition Disorders/diagnosis , Child Nutrition Disorders/physiopathology , Child Nutritional Physiological Phenomena , Child, Preschool , Developing Countries , Extensively Drug-Resistant Tuberculosis/diagnosis , Extensively Drug-Resistant Tuberculosis/drug therapy , Extensively Drug-Resistant Tuberculosis/mortality , Female , HIV Infections/diagnosis , HIV Infections/drug therapy , Humans , Male , Malnutrition/diagnosis , Malnutrition/physiopathology , Nutritional Status , Referral and Consultation , Retrospective Studies , Risk Factors , South Africa/epidemiology , Time Factors , Treatment Outcome , Tuberculosis, Multidrug-Resistant/diagnosis , Tuberculosis, Multidrug-Resistant/drug therapy
2.
Int J Exp Pathol ; 73(5): 551-63, 1992 Oct.
Article in English | MEDLINE | ID: mdl-1419774

ABSTRACT

he comparative teratogenicity of nine retinoids in Wistar rats was investigated. The compounds studied and dose levels tested (mg/kg) were: all-trans-retinoic acid (TRA), 6.25, 12.5, 25, 50, 100; etretinate (ETR), 25, 50; acitretin (ACIT), 25, 50; 13-cis-retinoic acid (13CRA), 100, 200; and five retinamides, each at 300 and 600 mg/kg, N-(4-hydroxyphenyl)-retinamide (4HPR); N-tetrazol-5-ylretinamide (TZR); N-butylretinamide (NBR); N-ethylretinamide (NER); 13-cis-N-ethylretinamide (13CNER). Retinoids were administered by oral intubation on days 10 and 11 post coitum (p.c.). Dams were killed on day 22 p.c. and examinations carried out to assess teratogenic potential. TRA, ETR, ACIT, 13CRA and 4HPR increased the incidence of resorptions. The incidence of abnormal fetuses, irrespective of the specific abnormalities induced, was markedly increased (50-100%) by TRA, ETR, ACIT, 13CRA and 4HPR, whereas TZR and NBR caused moderate increases (20-50%), and NER and 13CNER induced mild increases (10-20%). The incidences of CNS, craniofacial and urinogenital defects were generally high with TRA, ETR, ACIT and 13CRA. Cardiac vessel defects were markedly increased by 4HPR. Using a number of criteria, a generalized ranking order of the toxicity of the compounds was drawn up: TRA > ETR > ACIT > 13CRA > 4HPR > TZR identical to NBR > NER identical to 13CNER. The ranked order of relative in-vivo teratogenicity for the nine retinoids is compared with a previously reported in-vitro assessment of the compounds using a rat whole embryo culture technique.


Subject(s)
Abnormalities, Drug-Induced , Retinoids/toxicity , Animals , Dose-Response Relationship, Drug , Embryo Loss/chemically induced , Female , Pregnancy , Rats , Rats, Wistar
4.
Lab Anim ; 23(4): 295-301, 1989 Oct.
Article in English | MEDLINE | ID: mdl-2811267

ABSTRACT

As little comprehensive baseline data are available on age-related haematological changes in genetically-defined rat strains, the haematology of female F344 rats is described in animals sampled at 2, 4, 8, 20, 66 and 121 weeks of age. Values for Hb, RBC and PCV increased from 2 weeks of age to reach adult levels at 8 weeks, whereas MCV, MCH and reticulocyte counts were high initially but decreased to reach the adult range at 8 weeks. Between 66 and 121 weeks, reticulocyte counts were significantly increased and values for MCHC significantly decreased. Lymphocytes were the predominant white cell type in each age group. The absolute numbers of neutrophils and lymphocytes showed slight variations between 2 and 66 weeks and both cell types increased significantly between 66 and 121 weeks. Platelet counts showed no overall age-related trends. Fibrinogen values increased from 2 weeks of age to reach the adult level at 8 weeks. One animal of the 14 sampled at 121 weeks showed changes in the blood, liver and spleen consistent with a diagnosis of lymphoid leukaemia.


Subject(s)
Aging/blood , Blood Cell Count/veterinary , Hematologic Tests/veterinary , Rats, Inbred F344/blood , Rats, Inbred Strains/blood , Animals , Blood Sedimentation , Body Weight , Erythrocyte Count/veterinary , Erythrocyte Indices , Female , Hematocrit/veterinary , Leukemia, Lymphoid/blood , Leukemia, Lymphoid/veterinary , Leukocyte Count/veterinary , Male , Platelet Count/veterinary , Rats , Reference Values , Rodent Diseases/blood
5.
Br J Exp Pathol ; 69(4): 525-36, 1988 Aug.
Article in English | MEDLINE | ID: mdl-3179200

ABSTRACT

Three nephrectomy specimens with transitional cell carcinoma (TCC) of the renal pelvis were thoroughly examined by both light and scanning electron microscopy. The tumours as well as the urothelium of the upper urinary tract were studied. In all three cases, extensive areas of the urothelium, even in places remote from the tumours, were found by scanning electron microscopy (SEM) to be covered by pleomorphic microvilli. This suggests that there is a widespread failure of differentiation of the urothelium to a much greater extent than can be appreciated by conventional light microscopy.


Subject(s)
Carcinoma, Transitional Cell/ultrastructure , Kidney Neoplasms/ultrastructure , Urinary Tract/ultrastructure , Adult , Aged , Epithelium/ultrastructure , Humans , Kidney Calices/ultrastructure , Kidney Pelvis/ultrastructure , Male , Microscopy, Electron, Scanning , Middle Aged , Ureter/ultrastructure , Urinary Bladder/ultrastructure
6.
Br J Exp Pathol ; 68(3): 343-50, 1987 Jun.
Article in English | MEDLINE | ID: mdl-3620329

ABSTRACT

This study examines the effects of in-vivo immune regulation by vitamin A acetate (VAA) and 13-cis-retinoic acid (13-CRA) on in-vitro accessory cell function. Mice were fed a control diet, or diet containing VAA or 13-CRA, and monitored by body weight gains and diet consumptions at weekly intervals. At 4, 7 and 12 weeks mice were killed, differential blood counts performed and accessory cells isolated from lymphomedullary tissues. Histology confirmed that the chief feature of the lymphomedullary organs of the VAA-fed animals was an expansion of the splenic marginal zone and the paracortical region of the lymph nodes. There was an increase in the number of accessory cells present, and this included both dendritic cells and macrophages. The accessory cell function of these cells was also increased, as evidenced by both alloproliferative and allocytotoxic responses in vitro. In 13-CRA-fed animals the effects were similar to those seen with VAA, but were less pronounced. We suggest that the primary effects of these compounds on in-vivo immunoregulation could be due to their promotion of accessory cell function.


Subject(s)
Antigen-Presenting Cells/drug effects , Tretinoin/pharmacology , Vitamin A/analogs & derivatives , Animals , Cell Count , Cytotoxicity, Immunologic/drug effects , Dendritic Cells/drug effects , Diterpenes , Female , Leukocyte Count/drug effects , Lymph Nodes/drug effects , Lymph Nodes/immunology , Macrophages/drug effects , Mice , Mice, Inbred Strains , Retinyl Esters , Spleen/drug effects , Spleen/immunology , Vitamin A/pharmacology
7.
Br J Exp Pathol ; 68(2): 215-23, 1987 Apr.
Article in English | MEDLINE | ID: mdl-3580281

ABSTRACT

Mid-gestation rat conceptuses were cultured for 48 h in serum containing the retinoids all-trans-retinoic acid (TRA), 13-cis-retinoic acid (13-CRA), etretinate (ETR), etretin or one of six retinamides at concentrations ranging from 0.5 to 400 micrograms/ml. TRA was toxic at a concentration of 0.5 microgram/ml. 13-CRA and etretin caused abnormal development at 1.0 microgram/ml. However, the six retinamides were less toxic and adverse developmental effects were only evident at concentrations of 50 or 100 micrograms/ml. ETR was without effect at 100 micrograms/ml, the highest dose level of this compound tested. In vivo, TRA, 13-CRA and ETR are highly teratogenic. In this culture system, TRA and 13-CRA caused abnormal development at very low concentrations but in contrast, ETR was non-toxic at 100 micrograms/ml. Therefore these findings indicate that in vivo, maternal pharmacokinetics, and bioactivation in particular, play a major role in inducing abnormal development. Cis/trans isomerization was not a major determinant of toxicity. However, there appeared to be a relationship between abnormal development and the actual or estimated pKa values of the 10 retinoids tested.


Subject(s)
Abnormalities, Drug-Induced/etiology , Retinoids/toxicity , Teratogens , Animals , Dose-Response Relationship, Drug , Embryo, Mammalian/drug effects , In Vitro Techniques , Limb Deformities, Congenital , Neural Tube Defects/chemically induced , Protein Biosynthesis , Rats , Rats, Inbred Strains
9.
Carcinogenesis ; 7(5): 767-74, 1986 May.
Article in English | MEDLINE | ID: mdl-2421938

ABSTRACT

The direct effects of sodium saccharin and sodium cyclamate on the morphology of organ cultures of normal rat bladder have been studied by histology and scanning electron microscopy (SEM). Untreated cultures retained histologically normal urothelia up to 89 days with cell surface features characteristic of mature, fully differentiated superficial cells and maturing intermediate cells. Continuous treatment with either sodium saccharin (6 or 12 mM) or sodium cyclamate (12 or 24 mM) induced progressive abnormalities in the cultured urothelium. Acute toxicity was not seen but focal necrosis was observed with the higher dose of each compound and histological abnormalities were more severe with the higher doses. Sodium saccharin induced mild hyperplasia of the urothelium on the surface of the culture and foci of altered epithelial polarity from 14 days; abnormal nuclear staining plus changes in the basal lamina were evident from 28 days and were pronounced from 56 days onwards. Hyperplasia of the urothelium over the explants was mild but there were extensive epithelial outgrowths onto the culture support. In general, sodium cyclamate induced more severe changes than did sodium saccharin, with alterations in epithelial cell polarity plus basal cell changes from 14 days and focal nodular urothelial hyperplasia over the explant and gross hyperplasia between the explant and culture support and in the outgrowth from 28 days. The severe and rapid surface changes, evident by SEM, were similar both in saccharin-treated and in cyclamate-treated cultures. There was some early loss of superficial cells to reveal underlying immature cells which, together with the remaining mature cells, developed abnormal blebs and processes. From 14 days small immature cells were located at the culture surface between the mature cells. These were covered by a variety of membrane protrusions including long pleomorphic microvilli. Sodium cyclamate-treated cultures mostly had fewer small membrane protrusions than sodium saccharin-treated cultures but more pleomorphic microvilli. These morphological changes induced in the rat urothelium in vitro by direct treatment with sodium saccharin and sodium cyclamate are thus similar to those described previously in association with in vivo long-term feeding studies of sodium saccharin to rats and with both in vivo and in vitro treatment of the rat urothelium with the bladder carcinogen N-methyl-N-nitrosourea (MNU).


Subject(s)
Cyclamates/toxicity , Saccharin/toxicity , Urinary Bladder/drug effects , Animals , Epithelium/pathology , Epithelium/ultrastructure , Female , Hyperplasia , Methylnitrosourea , Microscopy, Electron, Scanning , Organ Culture Techniques , Rats , Rats, Inbred F344 , Time Factors , Urinary Bladder/pathology , Urinary Bladder/ultrastructure , Urinary Bladder Neoplasms/chemically induced
10.
Carcinogenesis ; 6(7): 1047-54, 1985 Jul.
Article in English | MEDLINE | ID: mdl-4017171

ABSTRACT

Untreated organ cultures of normal rat bladder can be maintained for long periods, up to 160 days, in a supplemented Waymouth's medium MB 752/1. During that time, the urothelium retains a similar appearance to that seen in vivo, namely a three-cell thick epithelium with specialised superficial cells whose characteristic surface features are identifiable by scanning electron microscopy. These superficial cells cover the major part of the explants, but the surface features of basal and intermediate cells can be observed on the cut edges and re-epithelialising surfaces of the explant. These are described and illustrated. When normal cultures are treated with the direct-acting carcinogen, N-methyl-N-nitrosourea (MNU), the in vitro response of the urothelium resembles to a certain extent the in vivo response to MNU instilled directly into the bladder. A histological progression is seen through mild to severe dysplasia which resembles carcinoma in situ. However, no marked changes in growth pattern, such as the development of papillary or nodular hyperplasia are seen. It is suggested that this is related to the failure of the vascular and stromal elements of the explants to respond to MNU treatment in vitro. The development of urothelial dysplasia is reflected by marked changes in cell surface differentiation, including development of pleomorphic microvilli, which closely resemble those seen following MNU treatment in vivo. These changes appeared earlier and were far more severe in vitro than in vivo. The significance of pleomorphic microvilli in bladder cultures is considered. A few were seen in control cultures but primarily on epithelial outgrowths onto the Millipore filter support, suggesting a relationship to the distance of the urothelium from viable stromal support. In the MNU-treated cultures, they were numerous and found on the surface of cells covering most of the explants. They were not solely related to the proliferative state of the urothelium in these cultures. This in vitro culture system provides a useful model with which to study the effects on the urothelium of various known and suspect carcinogens.


Subject(s)
Cell Transformation, Neoplastic , Methylnitrosourea/toxicity , Nitrosourea Compounds/toxicity , Urinary Bladder Neoplasms/chemically induced , Animals , Cell Differentiation/drug effects , Cell Membrane/ultrastructure , Epithelial Cells , Epithelium/ultrastructure , Female , Microscopy, Electron, Scanning , Microvilli/ultrastructure , Organ Culture Techniques , Rats , Rats, Inbred F344 , Time Factors , Urinary Bladder/cytology , Urinary Bladder/drug effects , Urinary Bladder/ultrastructure , Urinary Bladder Neoplasms/pathology
11.
Carcinogenesis ; 6(4): 595-604, 1985 Apr.
Article in English | MEDLINE | ID: mdl-3872740

ABSTRACT

Transforming growth factors alpha and beta (TGF-alpha and TGF-beta) isolated from normal mouse kidney induced gross morphological changes in rat urothelial cells maintained in organ culture. These morphological effects are similar to those observed after long-term treatment of rat bladder organ cultures with the carcinogen N-methyl-N-nitrosourea (MNU) or the promoting agents sodium saccharin and sodium cyclamate. Cultures were treated continuously with 5-25 micrograms/ml of Bio-Gel P-30-purified TGF containing both TGF-alpha and TGF-beta between days 1 and 14 in culture, or with 5 micrograms/ml from days 28 to 42. Controls received 1-10 ng/ml epidermal growth factor (EGF) or control medium. Untreated controls retained a normal urothelium throughout the period of study. Mature superficial-type cells covered most of the surface and less mature forms appeared on the cut sides and damaged areas where cells followed the normal pattern of urothelial differentiation. EGF at 5 and 10 ng/ml caused necrosis of the entire urothelium but at 1 and 2 ng/ml had minimal effects on histology and scanning electron microscopical appearance up to 14 days in culture. Crude P-30-purified TGFs induced a series of dose-related changes from 4 days, which were maximal at 8 days and persisted or decreased between 8 and 14 days. These included hyperplasia, loss of epithelial polarity, hyperchromasia and elongation of basal cells between the overlying cell layers to reach the culture surface. Scanning electron microscopy showed the appearance at the culture surface of immature cells with gross surface abnormalities including large numbers of blebs, stubby microvilli and long pleomorphic microvilli. Immature cells on the sides of the culture and in damaged areas developed similar features. At crude TGF doses of 10 micrograms/ml many superficial cells were rounded, some became cystic and epithelial necrosis was observed. Cultures treated with h.p.l.c.-purified TGF-beta at 80 ng/ml in the presence of 2 ng/ml EGF showed similar effects to those treated with 5 micrograms/ml P-30-purified TGF. Fully differentiated cultures treated from 28 to 42 days with crude TGF, showed changes similar to those seen in early cultures. However, histological changes, particularly basal cell elongation were more widespread and there was an abnormal development of globular processes between the membrane ridges of mature superficial cells. Neither crude TGF nor EGF stimulated growth in soft agar of isolated epithelial cells from freshly killed rats or organ cultures pretreated for 7 days with EGF or TGF.(ABSTRACT TRUNCATED AT 400 WORDS)


Subject(s)
Cell Transformation, Neoplastic/ultrastructure , Peptides/pharmacology , Urinary Bladder/ultrastructure , Animals , Cell Transformation, Neoplastic/chemically induced , Epidermal Growth Factor/pharmacology , Male , Methylnitrosourea/pharmacology , Mice , Microscopy, Electron, Scanning , Organ Culture Techniques , Peptides/isolation & purification , Rats , Rats, Inbred F344 , Transforming Growth Factors , Urinary Bladder/drug effects
12.
Ciba Found Symp ; 113: 168-90, 1985.
Article in English | MEDLINE | ID: mdl-3849405

ABSTRACT

Bladder cancer has a 70% recurrence rate within five years and a high associated mortality. It commonly occurs in one or both of two predominant growth/behaviour patterns: either well-differentiated, relatively benign exophytic papillary lesions, or flat, poorly differentiated invasive carcinoma usually arising from carcinoma-in-situ. We have used the F344 rat treated with N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) as a model for the papillary disease, and the BBN-treated B6D2F1 mouse for flat, invasive bladder carcinoma. In the rat, carcinogenesis is a multistage process and several retinoids will delay or even halt the development of bladder cancer. Inhibition of carcinogenesis is not complete, but there is a consistent reduction in the time-related incidence of papillomas and carcinomas and a concomitant improvement in the overall differentiation of the urothelium. In the BBN/mouse model, retinoids also have anticarcinogenic activity but interpretation of the results is more complicated. Unlike the F344 rat, the B6D2F1 mouse has a non-uniform response to BBN; not all mice develop bladder cancer even after treatment with very high doses of BBN and in those that do, more than one mechanism of carcinogenesis may be involved. Individual retinoids differ markedly in their ability to modulate bladder carcinogenesis in rodents; the behaviour of one analogue cannot be predicted automatically from data obtained with another. Combined data from rodent trials in this and other laboratories have identified N-(4-hydroxyphenyl)retinamide (HPR) as the most anticarcinogenic retinoid tested so far for the rodent bladder. It is also less toxic in rodents and better tolerated in humans than either 13-cis-retinoic acid or etretinate, two retinoids currently used in dermatological practice. A prophylactic chemopreventive trial of HPR in bladder cancer patients starting in 1985 will be centered on the Middlesex Hospital, London.


Subject(s)
Retinoids/therapeutic use , Urinary Bladder Neoplasms/drug therapy , Animals , Butylhydroxybutylnitrosamine , Cell Transformation, Neoplastic/chemically induced , Cell Transformation, Neoplastic/drug effects , Cell Transformation, Neoplastic/pathology , Disease Models, Animal , Epithelium/drug effects , Epithelium/pathology , Mice , Mice, Inbred Strains , Rats , Rats, Inbred F344 , Retinoids/administration & dosage , Time Factors , Urinary Bladder Neoplasms/chemically induced , Urinary Bladder Neoplasms/diet therapy
14.
Ciba Found Symp ; 113: 220-51, 1985.
Article in English | MEDLINE | ID: mdl-3875458

ABSTRACT

The long-term effects of N-ethylretinamide (NER) on the haematology of the rat, and the dose-related effects of retinoids on lymphoid organs of the mouse and rat were investigated. Retinoid-induced long-bone changes were used to develop a method for quantifying skeletal effects. This technique was used to investigate the activity of five retinamides in inducing long-bone changes in the rat. The ability of non-steroidal anti-inflammatory compounds (NSAICs) to prevent retinoid-induced skeletal effects was examined, and preliminary investigations made into the mechanisms of retinoid-induced long-bone remodelling. NER-fed rats had reduced red blood cell counts and fibrinogen values. Retinoids caused dose-related proliferation of the spleen and lymph nodes in the mouse and to a lesser extent in the rat. They induced dose-related reductions in femoral diaphysis and medullary cavity diameters in both rats and mice. Aspirin prevented NER-induced changes of rat long bones, but subsequent studies indicated this effect may be closely dependent on the dose level of both the retinoid and NSAIC administered. Retinoids induce rapid long-bone remodelling in the rat which tends to revert on feeding a control diet, but remodelling processes are different in the young growing rat and the mature animal.


Subject(s)
Blood/drug effects , Bone and Bones/drug effects , Lymphoid Tissue/drug effects , Retinoids/toxicity , Animals , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Body Weight/drug effects , Dose-Response Relationship, Drug , Female , Femur/drug effects , Femur/ultrastructure , Mice , Mice, Inbred Strains , Organ Size/drug effects , Rats , Rats, Inbred F344 , Retinoids/administration & dosage , Species Specificity , Tretinoin/administration & dosage , Tretinoin/analogs & derivatives
15.
Vet Rec ; 115(22): 571-4, 1984 Dec 01.
Article in English | MEDLINE | ID: mdl-6523682

ABSTRACT

The use of cystoscopy is advocated as an aid to the early differential diagnosis of disease of the canine bladder. Techniques are described for carrying out urethroscopy and cystoscopy in both male and female dogs using modern medical diagnostic instruments. Males were examined with flexible paediatric bronchofibrescopes, which permitted urethroscopy and cystoscopy, but to obtain extensive biopsies or undertake cauterisation of the bladder surface with rigid endoscopes, a simple perineal urethrostomy was necessary. The bladder of females, on the other hand, was examined by cystoscopy and biopsied using standard rigid cystoscopes and resectoscopes.


Subject(s)
Cystoscopy/veterinary , Dog Diseases/diagnosis , Urethra/pathology , Urinary Bladder Diseases/veterinary , Urinary Bladder/pathology , Animals , Biopsy/veterinary , Cystoscopes , Cystoscopy/methods , Dogs , Female , Male , Urinary Bladder Diseases/diagnosis
16.
Food Chem Toxicol ; 22(9): 755-60, 1984 Sep.
Article in English | MEDLINE | ID: mdl-6386630

ABSTRACT

A review of various in vivo and in vitro studies indicates that saccharin has second-stage promoting activity in the rat bladder. In vitro, its effect on the human bladder is comparable to that on the rat bladder, and it produces marked hyperplasia of the urothelium. It is clear from the evidence available that the role of saccharin in carcinogenesis of the urinary bladder in vivo is complex. Given before initiation it may possibly act as a co-carcinogen and influence the response of the urothelium to initiating carcinogens. Post-initiation it can cause clonal expansion of preneoplastic cells, thus providing a large population of susceptible cells, which must still undergo some further genetic modification before they can express their full malignant potential. It is possible that saccharin, if present in sufficiently high concentration for a long enough time, may also catalyse this final malignant conversion. Nevertheless, saccharin is not a powerful co-carcinogen or promoting agent by comparison with classical skin promoters such as TPA, and it has been shown to affect tumour prevalence only if present in high concentrations over a prolonged period of time.


Subject(s)
Carcinogens , Saccharin/toxicity , Urinary Bladder Neoplasms/chemically induced , Animals , Cell Membrane/drug effects , Cocarcinogenesis , Enzyme Induction/drug effects , Epithelium/drug effects , Humans , Organ Culture Techniques , Ornithine Decarboxylase/biosynthesis
17.
Food Chem Toxicol ; 22(7): 559-72, 1984 Jul.
Article in English | MEDLINE | ID: mdl-6540231

ABSTRACT

Several multivariate statistical methods are available which can alleviate the problems of analysing the large volumes of data generated from toxicological experiments. One such technique, principal components analysis, provides a method for exploring the relationships between a number of variables (such as blood parameters) and for eliminating redundant data if strong correlations exist between the characters. It also provides a method for clustering individuals, which may reveal similarities between animals in a treatment group or highlight individual 'outliers'. The application of principal components analysis to a set of haematological data from a trial evaluating the efficacy of a synthetic retinoid against carcinogen-induced bladder cancer in the rat has clearly shown, in two bivariate plots, that while some animals in the carcinogen-treated groups were normal, others were anaemic and that animals fed the synthetic retinoid and killed at 1 year had a microcytic anaemia. A full exploration of the data using conventional univariate statistical analysis would have involved at least 28 graphic representations of the data, as well as the interpretation of more than 130 means and SDs. Principal components analysis provides a valuable additional tool for the statistical analysis and exploration of toxicological data, but it must be used in conjunction with univariate or other multivariate methods if hypothesis testing is required. The use of multivariate techniques in toxicology may best be assessed by their practical application to toxicological data, and this paper presents such an evaluation with the aim of encouraging further exploration of the usefulness of principal components analysis. The raw data on which most analyses have been carried out are given.


Subject(s)
Analysis of Variance , Antineoplastic Agents/toxicity , Blood/drug effects , Tretinoin/analogs & derivatives , Urinary Bladder Neoplasms/drug therapy , Animals , Antineoplastic Agents/therapeutic use , Blood Cell Count , Blood Cells/drug effects , Butylhydroxybutylnitrosamine/toxicity , Drug Evaluation, Preclinical , Erythrocytes/drug effects , Female , Hemoglobins/metabolism , Rats , Rats, Inbred F344 , Time Factors , Tretinoin/therapeutic use , Tretinoin/toxicity , Urinary Bladder Neoplasms/blood , Urinary Bladder Neoplasms/chemically induced
18.
Br J Cancer ; 50(1): 63-75, 1984 Jul.
Article in English | MEDLINE | ID: mdl-6743515

ABSTRACT

The carcinogenic activity of the alkylating agent methyl methanesulphonate (MMS) was investigated in the F344 rat bladder, both untreated and pretreated with a single threshold dose of N-methyl-N-nitrosourea (MNU). On its own, 6 doses of 2.5 mg MMS produced a 7% incidence of bladder cancer. After a single intravesical instillation of MNU, the same MMS treatment produced a bladder cancer incidence of 56%. This was significantly higher than the incidence (24%) observed after treatment with MNU alone, and greater than the sum of the lesions produced by either treatment alone. By reference to the mouse skin multistage carcinogenesis model, it is argued that MMS is a complete, albeit weak carcinogen with little initiating but powerful late-stage activity. Its promoting activity is most probably attributable to its potent mitogenic action and in this model it is analogous to a stage 2, rather than a stage 1 skin promoter.


Subject(s)
Cocarcinogenesis , Methyl Methanesulfonate/toxicity , Urinary Bladder Neoplasms/chemically induced , Animals , Carcinoma, Transitional Cell/chemically induced , Carcinoma, Transitional Cell/pathology , Drug Synergism , Female , Hyperplasia/chemically induced , Hyperplasia/pathology , Methylnitrosourea/toxicity , Rats , Rats, Inbred F344 , Urinary Bladder/pathology , Urinary Bladder Neoplasms/pathology
19.
Carcinogenesis ; 5(7): 949-54, 1984 Jul.
Article in English | MEDLINE | ID: mdl-6733857

ABSTRACT

The metabolism of benzidine and 2-naphthylamine, two aromatic amines which are carcinogenic for the human, was investigated in human and rat bladder organ cultures. There was little oxidative metabolism of either carcinogen in either species. In particular, N-hydroxy-2-naphthylamine, a proximate carcinogen of 2-naphthylamine could not be detected. In contrast, large amounts of the acetylated metabolites, N-acetylbenzidine, N,N-diacetylbenzidine and N-acetyl-2-naphthylamine were formed both in rat and human bladder cultures. The results suggest that metabolism of these carcinogens in situ in the bladder is unlikely to contribute to their carcinogenic effect but instead may have a positive protective role.


Subject(s)
2-Naphthylamine/metabolism , Benzidines/metabolism , Naphthalenes/metabolism , Urinary Bladder/metabolism , Acetyltransferases/analysis , Animals , Biotransformation , Carbon Radioisotopes , Female , Humans , Hydroxylation , Male , Organ Culture Techniques , Rats , Rats, Inbred F344 , Tritium
20.
J Pathol ; 143(2): 103-16, 1984 Jun.
Article in English | MEDLINE | ID: mdl-6737117

ABSTRACT

The effects of x-irradiation on the subcellular structure of the human urinary bladder were investigated by electron microscopic examination of biopsies taken during check cystoscopies from 25 patients between 1 month and 22 years after completion of a course of therapeutic radiation. All tissues of the bladder wall were damaged to some extent by the treatment. In the urothelium this was reflected by the development of more than the usual numbers of lysosomes and autophagic vacuoles in all cell layers. In the bladder wall, large often binucleate or multinucleate fibroblasts were prominent and persistent in all specimens and were associated with the development of progressive fibrosis. The vasculature and the muscle coats of the bladder wall were also damaged. In the blood vessels many endothelial cells were oedematous or necrotic and some intravascular coagulation was also observed. Smooth muscle cells became oedematous soon after irradiation, and after longer time intervals there was focal death and loss of individual muscle cells. The observed degeneration and extensive necrosis of the bladder wall, which involved severe destruction and disorganization of the muscular layers, is sufficient to explain the clinical sequelae of bladder irradiation, namely loss of elasticity, reduced capacity and incomplete micturition with residual urine.


Subject(s)
Radiation Injuries/pathology , Radiotherapy/adverse effects , Urinary Bladder/radiation effects , Adult , Aged , Blood Vessels/radiation effects , Blood Vessels/ultrastructure , Connective Tissue/radiation effects , Epithelium/radiation effects , Epithelium/ultrastructure , Female , Humans , Male , Microscopy, Electron , Middle Aged , Muscle, Smooth/radiation effects , Muscle, Smooth/ultrastructure , Nerve Tissue/radiation effects , Urinary Bladder/blood supply , Urinary Bladder/ultrastructure
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