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1.
Scand J Rheumatol ; 53(2): 104-111, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37905707

RESUMO

OBJECTIVES: To translate the Assessment of SpondyloArthritis international Society (ASAS) Health Index (HI) Environmental Factors Item Set (EFIS) into Swedish and culturally adapt it for a Swedish context, and to assess the construct validity of the Swedish version of the ASAS HI and test-retest reliability in ASAS HI and EFIS in Swedish patients with ankylosing spondylitis (AS). METHOD: Translation and cross-cultural adaptation of the EFIS were carried out according to a forward-backward procedure consisting of five steps. The construct validity of the ASAS HI was tested using Spearman correlation with standard health outcomes for axial spondyloarthritis (axSpA). Reliability was analysed by internal consistency with the Cronbach's alpha coefficient for ASAS HI, and test-retest reliability with intraclass correlation coefficients (ICCs) for ASAS HI and kappa agreement for the individual items of EFIS. RESULTS: The translation of EFIS showed acceptable face and content validity. ASAS HI showed an acceptable internal consistency (Cronbach's alpha 0.79), and excellent test-retest reliability (ICC 0.87). Test-retest reliability for EFIS showed varied results, with kappa agreement for the individual items ranging from poor (-0.027) to good (0.80). CONCLUSIONS: The Swedish version of ASAS HI proved to be valid and reliable and is recommended for assessing the impact of AS on global functioning and health. A Swedish version of EFIS has been produced and uploaded on the ASAS website. The EFIS proved to have acceptable face and content validity, and may contribute to the contextual interpretation of the ASAS HI.


Assuntos
Espondilartrite , Espondilite Anquilosante , Humanos , Reprodutibilidade dos Testes , Suécia , Inquéritos e Questionários , Psicometria
2.
Eur J Cancer ; 50(3): 656-62, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24300455

RESUMO

AIM: To evaluate the expression and prognostic value of the epidermal growth factor receptor HER3 in patients with primary colorectal cancer (CRC) and corresponding lymph node metastases. PATIENT AND METHODS: HER3 expression was analysed immunohistochemically (IHC) in primary tumours and in corresponding lymph node metastases from 236 patients with stage II and III CRC. In 58 primary tumours, fluorescence in situ hybridisation (FISH) detection was performed. RESULTS: HER3 was detected at high frequency in the cell membrane. Seventy percent of the primary tumours had a high HER3 expression compared to 75% in the lymph node metastases. HER3 expression in the primary tumour was an independent prognostic factor for overall survival in the entire group of patients (p=0.026) and in the subgroup of patients with colon cancer stage II (p=0.030). A high HER3 expression in the primary tumour was associated with worse clinical outcome. The expression of HER3 was homogenous within the primary tumour (r=0.9, p<0.0001) and correlated with the HER3 expression in corresponding lymph node metastases (r=0.6, p<0.0001). No gene amplification with respect to HER3 was seen in primary tumours using FISH analysis. CONCLUSION: A high HER3 expression was found in 70% of the primary CRC tumours and in 75% of the corresponding lymph node metastases. HER3 expression in the tumour was an independent prognostic factor, where a high HER3 expression was associated with worse clinical outcome. There was a correlation in HER3 expression between primary tumour and corresponding lymph node metastases.


Assuntos
Neoplasias Colorretais/enzimologia , Neoplasias Colorretais/patologia , Receptor ErbB-3/biossíntese , Idoso , Biomarcadores Tumorais/biossíntese , Biomarcadores Tumorais/genética , Neoplasias Colorretais/genética , Intervalo Livre de Doença , Feminino , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Linfonodos/enzimologia , Linfonodos/patologia , Metástase Linfática , Masculino , Prognóstico , Receptor ErbB-3/genética , Análise de Sobrevida
3.
Anticancer Res ; 30(2): 645-51, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20332484

RESUMO

AIM: To investigate thymidylate synthase (TS) expression in primary colorectal cancer (CRC) as a prognostic and predictive marker of benefit for adjuvant chemotherapy. PATIENTS AND METHODS: TS expression was immuno0-histochemically (IHC) assessed on tumors from 1,389 patients with stage II and III CRC randomly assigned to either surgery alone or surgery plus 5-fluorouracil (5-FU)-based adjuvant chemotherapy. RESULTS: In the subgroup treated with surgery alone (n=708), TS expression was prognostic using the classification of TS 0-1 versus 2-3 (p=0.045) as well as TS classified as 0-2 versus 3 (p=0.002). A high TS expression was associated with a shorter overall survival. Among patients with TS grade 3 (n=460), the subgroup treated with adjuvant chemotherapy had a significant longer OS (p=0.005). CONCLUSION: In this study TS, immunohistochemically assessed, is a prognostic factor in CRC patients treated with surgery alone. Patients with the highest level of TS expression (grade 3) had an improved clinical outcome following adjuvant 5-FU-based chemotherapy.


Assuntos
Neoplasias Colorretais/enzimologia , Timidilato Sintase/metabolismo , Adulto , Idoso , Neoplasias Colorretais/patologia , Neoplasias Colorretais/terapia , Feminino , Humanos , Técnicas Imunoenzimáticas , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida
4.
Eur J Clin Microbiol Infect Dis ; 23(6): 463-70, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15168141

RESUMO

To investigate the effects of mode of delivery and of necrotising enterocolitis on the faecal microflora, 140 infants born before 33 weeks of gestation were followed up for symptoms of necrotising enterocolitis. Stool samples for gas-liquid chromatography and culture were collected twice weekly, and, when necrotising enterocolitis was suspected, for 2 months. For each infant with necrotising enterocolitis (n=21), two control infants matched for birth weight and gestational age were selected from the remaining study population. In gas-liquid chromatography analysis, the faecal bacterial microflora of infants born via caesarean section differed significantly from the gut microflora of those born via the vaginal route. The intestinal microflora showed a significant alteration in the necrotising enterocolitis group at time of diagnosis. At the onset of necrotising enterocolitis, faecal colonisation with Enterococcus species and Candida albicans was significantly more frequent in symptomatic infants than in controls. In infants with positive blood cultures and positive intestinal biopsy cultures, concomitant stool samples revealed the same microbial pathogens. In conclusion, the intestinal microbial colonisation in preterm infants born by caesarean section differs from that in preterm infants born via the vaginal route. A significant change in faecal microbial colonisation seems to occur at the onset of necrotising enterocolitis. Pathogens detected in the stools at that time might have a causative role in the development of the disease.


Assuntos
Parto Obstétrico/métodos , Enterocolite Necrosante/microbiologia , Bactérias Gram-Negativas/isolamento & purificação , Bactérias Gram-Positivas/isolamento & purificação , Recém-Nascido Prematuro , Intestinos/microbiologia , Análise de Variância , Estudos de Casos e Controles , Cesárea , Contagem de Colônia Microbiana , Enterocolite Necrosante/epidemiologia , Enterocolite Necrosante/fisiopatologia , Fezes/microbiologia , Feminino , Seguimentos , Idade Gestacional , Humanos , Recém-Nascido , Masculino , Gravidez , Probabilidade , Valores de Referência , Estudos de Amostragem , Estatísticas não Paramétricas
5.
Acta Paediatr ; 92(1): 111-3, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12650310

RESUMO

AIM: To investigate the frequency of and risk factors for necrotizing enterocolitis (NEC) among infants of <33 wk of gestation. METHODS: Prospective follow-up of 140 inpatients. RESULTS: 26 (18.6%) subjects developed NEC stage I-III and 12 (8.6%) severe NEC (stage II-III). Breast milk fortifier and duration of morphine infusion emerged as the statistically significant factors associated with NEC stage I-III, but only the latter had a significant association with severe NEC. CONCLUSION: Future studies are needed to be established whether morphine is a causative factor in NEC.


Assuntos
Enterocolite Necrosante/etiologia , Morfina/efeitos adversos , Permeabilidade do Canal Arterial/tratamento farmacológico , Permeabilidade do Canal Arterial/epidemiologia , Enterocolite Necrosante/epidemiologia , Retardo do Crescimento Fetal/epidemiologia , Seguimentos , Idade Gestacional , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Morfina/administração & dosagem , Pneumatose Cistoide Intestinal/epidemiologia , Estudos Prospectivos , Surfactantes Pulmonares/uso terapêutico , Fatores de Risco , Índice de Gravidade de Doença
6.
Acta Paediatr ; 90(10): 1196-8, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11697435

RESUMO

UNLABELLED: Rotavirus and adenovirus infections in 308 infants hospitalized for longer than 1 wk, and cases with necrotizing enterocolitis, were screened in a neonatal unit during a 15 mo period, covering two rotavirus epidemics in the community. Altogether, 1020 stool samples were collected weekly until hospital discharge, and in necrotizing enterocolitis cases at the onset of symptoms, and tested for rotavirus and adenovirus by means of enzyme-linked immunosorbent assay. The positive samples were further analysed by polymerase chain reaction. Enzyme-linked immunosorbent assay revealed five adenovirus-positive cases, which were tested negative by polymerase chain reaction. Out of 16 necrotizing enterocolitis cases, one was adenovirus- and another rotavirus positive when tested by polymerase chain reaction, the latter having a concomitant Candida albicans septicaemia. CONCLUSION: Routine rotavirus and adenovirus screening in hospitalized neonates seems to be unnecessary. Viral diagnostic examinations should be considered in patients with necrotizing enterocolitis.


Assuntos
Infecções por Adenoviridae/diagnóstico , Infecções por Adenoviridae/epidemiologia , Infecção Hospitalar/diagnóstico , Infecção Hospitalar/epidemiologia , Hospitalização/estatística & dados numéricos , Triagem Neonatal , Infecções por Rotavirus/diagnóstico , Infecções por Rotavirus/epidemiologia , Humanos , Lactente , Recém-Nascido , Fatores de Tempo
7.
Clin Cancer Res ; 6(4): 1378-84, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10778966

RESUMO

Several studies have suggested that the intratumoral level of thymidylate synthase (TS) in colorectal tumors correlates with survival. We have studied the correlation between TS expression in primary rectal cancer and locoregional recurrence, distant metastases, and survival. TS enzyme levels were evaluated immunohistochemically using the specific monoclonal antibody TS 106 in paraffin-embedded tumors from 243 patients who had undergone primary surgery for rectal cancer during the years 1980-1993. All patients were included in prospective randomized trials aimed at determining the clinical value of a short preoperative course of local radiation therapy (five doses of 5 Gy each). With a median follow-up of 94 months (range, 43-202 months), it was observed by multivariate analysis that Dukes' stage and TS expression were independent prognostic markers of locoregional recurrence (P < 0.001 and P = 0.038, respectively) distant metastasis (P < 0.001 and P = 0.011, respectively) disease-free survival (P < 0.001 and 0.014, respectively), and overall survival (P < 0.001 and 0.020, respectively). By multivariate analysis, preoperative irradiation therapy showed a borderline improvement in locoregional recurrence (P = 0.051). No other factors, such as age, sex, differentiation of the tumor, or p53 expression, were noted to be independent prognostic factors for clinical outcome in these patients. We concluded that the intratumoral expression of TS in primary rectal cancer is an independent prognostic factor for locoregional recurrence, distant metastases, disease-free survival, and overall survival. Patients with low intratumoral TS expression had a significantly better outcome than those with high TS expression.


Assuntos
Adenocarcinoma/enzimologia , Neoplasias Retais/enzimologia , Timidilato Sintase/biossíntese , Adenocarcinoma/radioterapia , Adenocarcinoma/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Metástase Neoplásica , Recidiva Local de Neoplasia , Prognóstico , Estudos Prospectivos , Neoplasias Retais/radioterapia , Neoplasias Retais/cirurgia , Análise de Sobrevida , Taxa de Sobrevida , Resultado do Tratamento , Proteína Supressora de Tumor p53/biossíntese
10.
Anticancer Res ; 16(5A): 2713-7, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8917376

RESUMO

Folinic acid (leucovorin) is frequently used to augment and modulate the clinical activity of 5-fluorouracil (5-FU) in patients with advanced gastrointestinal (Gl) cancer. However, there are conflicting opinions concerning the optimal doses for these patients, and whether folinic acid modulates the clinical activity of 5-FU in patients with non-Gl cancer. To elucidate these questions, model experiments have been performed on human tumor cell lines in vitro to determine the modulatory activity of various concentrations of folinic acid on 5-FU mediated cytotoxicity using a clonogenic assay. Three cell lines of colon cancer and 3 of glioblastoma origin were exposed to 5-FU alone or with folinic acid for 24 hours. It was observed that relatively low concentrations of folinic acid enhanced the cytotoxicity of 5-FU against the colon cancer lines whereas higher concentrations were less effective. Folinic acid did not enhance the 5-FU mediated killing of the glioma cell lines at any concentration (0.01-100 micrograms/ml). On the contrary, folinic acid seemed to counteract the cytotoxic effect of 5-FU in a reasonably dose-dependent fashion. These results may suggest that the value of folinic acid in the treatment of non-Gl cancer with 5-FU should be evaluated within the framework of controlled clinical trials, and that high doses of folinic acid may not necessarily be more effective than low.


Assuntos
Antimetabólitos Antineoplásicos/farmacologia , Fluoruracila/farmacologia , Leucovorina/farmacologia , Neoplasias do Colo , Sinergismo Farmacológico , Glioblastoma , Humanos , Leucovorina/administração & dosagem , Células Tumorais Cultivadas/efeitos dos fármacos , Ensaio Tumoral de Célula-Tronco
11.
Scand J Gastroenterol ; 30(9): 876-9, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8578186

RESUMO

BACKGROUND: The purpose was to examine the epidemiology of Helicobacter pylori infection in Finnish children and adolescents. METHODS: Blood samples taken from healthy subjects (n = 461) 3-18 years old were studied cross-sectionally for the presence of H. pylori antibodies. Additionally, blood samples drawn in 1980, 1983, 1986, and 1989 from 74 children born in 1977 were tested. Serum IgG-class antibodies to H. pylori were determined by an enzyme immunoassay. RESULTS: In the cross-sectional series the mean antibody levels and the percentage of seropositive children increased with age. The overall seroprevalence was 10.2%. During the follow-up period from 3 to 12 years of age the seropositivity increased from 4.6% to 5.7%. On the basis of the seroconversions between 3 and 12 years of age the annual incidence of H. pylori infection was calculated to be only 0.3%. CONCLUSIONS: In children seropositivity for H. pylori of the IgG class is often a sign of an infection acquired in early childhood. It seems likely that the age-dependent increase in the seropositivity reflects cumulation of a chronic infection.


Assuntos
Infecções por Helicobacter/epidemiologia , Helicobacter pylori/imunologia , Adolescente , Distribuição por Idade , Anticorpos Antibacterianos/análise , Criança , Pré-Escolar , Estudos Transversais , Finlândia/epidemiologia , Seguimentos , Infecções por Helicobacter/sangue , Infecções por Helicobacter/imunologia , Helicobacter pylori/isolamento & purificação , Humanos , Técnicas Imunoenzimáticas , Imunoglobulina G/análise , Incidência , Prevalência , Estudos Soroepidemiológicos
12.
J Pediatr Gastroenterol Nutr ; 16(3): 273-7, 1993 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8492255

RESUMO

Over a 2.5-year period, 82 consecutive children complaining of recurrent abdominal pain underwent upper gastrointestinal endoscopy. Gastroscopy confirmed pathology in 48 of the children (58.5%). Four of the children, who also had undergone gastroscopy, had other diagnoses (lactose malabsorption, hydronephrosis, yersiniosis), and 30 of the children (36.6%) retained the initial diagnosis of recurrent abdominal pain syndrome. Gastritis was found in 48 of the children, 18 of whom (37.5%) had positive test results for Helicobacter pylori, based on histology and/or culture. Of 16 H. pylori-positive children tested, 12 (75%) also had an elevated concentration of IgG-class antibodies to H. pylori in their sera. Three of the children had duodenal ulcer disease, all of whom were H. pylori positive. Esophagitis was found in eight of the children with gastritis, all of whom were found to have gastroesophageal reflux. Our data suggest that among the children with recurrent abdominal pain syndrome, organic pathology is more common than was previously thought. Altogether 22% of the children with recurrent abdominal pain syndrome were infected with H. pylori.


Assuntos
Dor Abdominal/patologia , Gastrite/patologia , Dor Abdominal/etiologia , Adolescente , Criança , Pré-Escolar , Endoscopia Gastrointestinal , Feminino , Gastrite/complicações , Infecções por Helicobacter/complicações , Infecções por Helicobacter/patologia , Humanos , Masculino , Recidiva
13.
Methods Find Exp Clin Pharmacol ; 13(8): 579-82, 1991 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1956213

RESUMO

2-Mercaptoethanesulfonate (Mesna), which is used as a uroprotective agent during oxazaphosphorine treatment, was previously found to inhibit growth of several tumor cell lines in vitro. To test the possibility that this effect is due to the SH-group of mesna, other thiols have now been tested. It has been observed that L-cysteine, N-acetyl-L-cysteine and glutathione, on a molar basis, had effects similar to mesna on [3H]thymidine incorporations of several human tumor cell lines in vitro. The dose-response profiles were monophasic for some cell lines and biphasic for others. It is suggested that compounds with SH-groups, in relatively high concentrations, may be toxic for cells.


Assuntos
Mesna/farmacologia , Compostos de Sulfidrila/farmacologia , Células Tumorais Cultivadas/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Humanos , Relação Estrutura-Atividade
14.
Anticancer Res ; 11(2): 773-6, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1905905

RESUMO

2-Mercaptoethanesulfonate (mesna) is a nontoxic drug which upon intravenous and oral administration effectively prevents urothelial toxicity in cancer patients treated with oxazaphosphorines. Mesna is rapidly oxidized to dimesna in the blood. It is then taken up by kidney tubular cells in which it is reduced and excreted into the urine as mesna where it reacts with toxic metabolites. We have observed that mesna, but not dimesna, may inhibit growth of several human malignant cell lines in vitro. Some are extremely sensitive, whereas others are more or less resistant. It was found that 2/4 relatively resistant human bladder cancer cell lines turned sensitive upon repeated administrations of mesna and 5/5 cell lines appeared to be sensitive to mesna when grown in serum-free medium. The results seem to provide an explanation of the remarkable positive clinical effects of prolonged oral mesna treatment in patients with superficial bladder cancer.


Assuntos
Replicação do DNA/efeitos dos fármacos , Mesna/farmacologia , Neoplasias da Bexiga Urinária/tratamento farmacológico , Linhagem Celular , Ensaios de Seleção de Medicamentos Antitumorais , Cinética , Mesna/uso terapêutico , Proteínas de Neoplasias/biossíntese , Prolina/metabolismo , RNA Neoplásico/biossíntese , RNA Neoplásico/efeitos dos fármacos , Timidina/metabolismo , Uridina/metabolismo
15.
Artigo em Inglês | MEDLINE | ID: mdl-1908032

RESUMO

Unlike "conventional" oxazaphosphorines such as cyclophosphamide (CP) and ifosfamide, a relatively new drug termed 4-hydroperoxy-CP (4-HC) degrades spontaneously in water yielding phosphoramide mustard considered to be the activated cytotoxic metabolite. During this degradation a toxic, volatile factor termed acrolein is also formed. In order to examine the possible role of this compound in 4-HC-induced inhibition of tumor cell growth in vitro, 8 different established human tumor cell lines were cultured in the presence of 4-HC or equimolar concentrations of acrolein. It was observed that the cell lines differed widely with respect to sensitivity to these compounds. However, each individual cell line exhibited virtually identical sensitivities to both 4-HC and acrolein. The observation that 2-mercaptoethansulfonate (mesna), which is highly reactive with acrolein but not with phosphoramide mustard, could markedly reduce the cytotoxic activity of 4-HC indicates that acrolein may play an important role in 4-HC induced cell damage in vitro.


Assuntos
Acroleína/farmacologia , Ciclofosfamida/análogos & derivados , Células Tumorais Cultivadas/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Ciclofosfamida/farmacologia , Técnicas Citológicas , Humanos , Mesna/farmacologia
16.
Methods Find Exp Clin Pharmacol ; 12(10): 691-7, 1990 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2129247

RESUMO

2-Mercaptoethanesulfonate (mesna), which is used as an uroprotector during oxazaphosphorine therapy of cancer patients, was found to inhibit growth of several cultured human malignant cell lines in vitro. Dimesna, which is rapidly formed in the blood of mesna treated patients, had no effect and did not interfere with the growth inhibitory activity of mesna. For sensitive cell lines, complete growth inhibitions were usually observed at mesna concentrations of 10(-4) M. Higher concentrations were less toxic or even stimulated proliferation of some cell lines. There was no experimental evidence that the biphasic dose-response profiles were due to a more complete dimesna formation at high mesna concentrations. Since mesna, which is excreted in its monomeric form in urine, was reported to inhibit growth of superficial bladder cancer in patients, we examined the effects of repeated mesna administrations in cultures of bladder cancer cells. The results showed that this treatment caused growth inhibition of 2/4 "resistant" cell lines. The mechanisms by which mesna inhibits cell growth are unknown and it is not known if it acts selectively on malignant cells.


Assuntos
Antineoplásicos , Mesna/farmacologia , Animais , Divisão Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Humanos , Timidina/metabolismo , Trítio , Células Tumorais Cultivadas/efeitos dos fármacos
17.
Cancer Immunol Immunother ; 31(4): 221-5, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2143101

RESUMO

The aim of the present study was to analyze further the immunopotentiating effects of low doses of oxazaphosphorines. We examined 4-hydroperoxycyclophosphamide (4-HC) and mafosfamide, which degrade spontaneously in water without requiring liver enzymes to become active. Both drugs, at concentrations ranging from 0.01 microM to 1 microM, enhanced mitogenic responses of human lymphocytes. Higher concentrations were toxic. Acrolein, which is one of the degradation products of oxazaphosphorines, had similar effects. Immunopotentiation was not monocyte-dependent. Attempts to inactivate released acrolein with human serum reduced toxicity but the immunostimulating property of the drugs remained Similar effects were noted when lymphocytes were exposed to acrolein dissolved in serum. 2-Mercaptoethane-sulfonate (mesna), which is highly reactive with acrolein, reduced the toxicity of solutions of both oxazaphosphorines and acrolein. Immunopotentiation was not clearly demonstrable since mesna itself enhanced the responses. Pretreatment of lymphocytes with 4-HC or mafosfamide did not reduce the capacity of concanavalin A to induce suppressor cells. It is speculated that acrolein may play a role in oxazaphosphorine-induced enhancements of immune responses.


Assuntos
Acroleína/farmacologia , Aldeídos/farmacologia , Ciclofosfamida/análogos & derivados , Imunidade Celular/efeitos dos fármacos , Linfócitos T/efeitos dos fármacos , Antineoplásicos/farmacologia , Concanavalina A/farmacologia , Ciclofosfamida/farmacologia , Humanos , Linfócitos/efeitos dos fármacos , Linfócitos/fisiologia , Mitógenos/farmacologia , Mitose/efeitos dos fármacos , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/imunologia
18.
Methods Find Exp Clin Pharmacol ; 11(6): 391-7, 1989 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2747340

RESUMO

Oxazaphosphorines such as cyclophosphamide and ifosfamide must undergo hydroxylation at the carbon-4-atom of the oxazaphosphorine ring by liver enzymes before they spontaneously degrade to form the alkylating moiety. Some new oxazaphosphorines with different substitutions at the carbon-4-atom, however, undergo spontaneous hydrolysis when dissolved in water. Biological properties of these "activated" oxazaphosphophorines, which thus do not require biotransformation to liberate the alkylating moiety, have been studied extensively. We now demonstrate that the "activated" oxazaphosphorines, 4-(2-sulfonatoethylthio)-cyclophosphamide, 4-hydroperoxy-cyclophosphamide and 4-hydroperoxy-ifosfamide, present as aqueous solutions in wells of conventional microtest tissue culture plates release a votile factor which may penetrate into the media of neighboring cultures and strongly reduce their growth and viability. This phenomenon, which was temperature dependent, could be inhibited by cells or serum present in the drug solutions. Cyclophosphamide, ifosfamide or nitrogen mustard dissolved in water did not release detectable amounts of toxic factor. Acrolein, which is the only known votile metabolite of oxazaphosphorines, was also found to reduce cell growth in neighboring cultures, and its evaporation could be inhibited by cells and serum. It is concluded that the toxic votile factor, most likely acrolein, which is spontaneously released from certain oxazaphosphorines, may strongly affect cells in in vitro culture systems.


Assuntos
Sobrevivência Celular/efeitos dos fármacos , Ciclofosfamida/farmacologia , Ifosfamida/farmacologia , Células Tumorais Cultivadas/efeitos dos fármacos , Animais , Linhagem Celular , Fenômenos Químicos , Química , Ciclofosfamida/análogos & derivados , Humanos , Ifosfamida/análogos & derivados , Linfócitos/efeitos dos fármacos , Camundongos , Soluções , Temperatura
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