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1.
Clin Pharmacol Ther ; 101(3): 373-381, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-27564568

RESUMEN

We performed a genomewide association study (GWAS) of primary erythrocyte thiopurine S-methyltransferase (TPMT) activity in children with leukemia (n = 1,026). Adjusting for age and ancestry, TPMT was the only gene that reached genomewide significance (top hit rs1142345 or 719A>G; P = 8.6 × 10-61 ). Additional genetic variants (in addition to the three single-nucleotide polymorphisms [SNPs], rs1800462, rs1800460, and rs1142345, defining TPMT clinical genotype) did not significantly improve classification accuracy for TPMT phenotype. Clinical mercaptopurine tolerability in 839 patients was related to TPMT clinical genotype (P = 2.4 × 10-11 ). Using 177 lymphoblastoid cell lines (LCLs), there were 251 SNPs ranked higher than the top TPMT SNP (rs1142345; P = 6.8 × 10-5 ), revealing a limitation of LCLs for pharmacogenomic discovery. In a GWAS, TPMT activity in patients behaves as a monogenic trait, further bolstering the utility of TPMT genetic testing in the clinic.


Asunto(s)
Antimetabolitos Antineoplásicos/farmacocinética , Leucemia/tratamiento farmacológico , Mercaptopurina/farmacocinética , Metiltransferasas/genética , Antimetabolitos Antineoplásicos/administración & dosificación , Niño , Relación Dosis-Respuesta a Droga , Femenino , Estudio de Asociación del Genoma Completo , Genotipo , Humanos , Masculino , Mercaptopurina/administración & dosificación , Farmacogenética , Polimorfismo de Nucleótido Simple
2.
Heredity (Edinb) ; 117(2): 84-93, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27118154

RESUMEN

Biological nitrogen fixation (BNF) in soybeans is a complex process involving the interplay between the plant host and the symbiotic rhizobia. As nitrogen supply has a crucial role in growth and development, higher nitrogen fixation capacity would be important to achieve bigger plants and larger seeds, which were important selection criteria during plant domestication by humans. To test this hypothesis, we monitored the nitrogen fixation-related performance in 31 cultivated and 17 wild soybeans after inoculation with the slow-growing Bradyrhizobium diazoefficiens sp. nov. USDA110 and the fast-growing Sinorhizobium (Ensifer) fredii CCBAU45436. Our results showed that, in general, cultivated soybeans gave better performance in BNF. Electron microscopic studies indicated that there was an exceptionally high accumulation of poly-ß-hydroxybutyrate bodies in bacteroids in the nodules of all wild soybeans tested, suggesting that the C/N balance in wild soybeans may not be optimized for nitrogen fixation. Furthermore, we identified new quantitative trait loci (QTLs) for total ureides and total nodule fresh weight by employing a recombinant inbred population composed of descendants from a cross between a cultivated and a wild parent. Using nucleotide diversity (θπ), divergence index (Fst) and distribution of fixed single-nucleotide polymorphisms as parameters, we found that some regions in the total ureides QTL on chromosome 17 and the total nodule fresh weight QTL on chromosome 12 exhibited very low diversity among cultivated soybeans, suggesting that these were traits specially selected during the domestication and breeding process.


Asunto(s)
Domesticación , Glycine max/genética , Fijación del Nitrógeno , Bradyrhizobium/metabolismo , Mapeo Cromosómico , Hidroxibutiratos/metabolismo , Nitrógeno/metabolismo , Fitomejoramiento , Poliésteres/metabolismo , Polimorfismo de Nucleótido Simple , Sitios de Carácter Cuantitativo , Nódulos de las Raíces de las Plantas/microbiología , Sinorhizobium/metabolismo , Glycine max/microbiología , Simbiosis
3.
Phys Chem Chem Phys ; 16(42): 23320-8, 2014 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-25259763

RESUMEN

In this work, three novel pyrene cored small conjugated molecules, namely 1,3,6,8-tetrakis(6-(octyloxy)naphthalene-2-yl)pyrene (PY-1), 1,3,6,8-tetrakis((E)-2-(6-(n-octyloxy)naphthalene-2-yl)vinyl)pyrene (PY-2) and 1,3,6,8-tetrakis((6-(n-octyloxy)naphthalene-2-yl)ethynyl)pyrene (PY-3) have been synthesized by Suzuki, heck and Sonogashira organometallic coupling reactions, respectively. The effects of single, double and triple bonds on their optical, electrochemical, and thermal properties are studied in detail. These are all materials fluorescent and they have been used in organic light-emitting diodes (OLEDs) and their electroluminescent properties have been studied.

4.
Leukemia ; 27(5): 1139-45, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23183426

RESUMEN

The probability of survival is conventionally calculated from autologous hematopoietic cell transplantation (aHCT). Conditional survival takes into account the changing probability of survival with time survived, but this is not known for aHCT populations. We determined disease- and cause-specific conditional survival for 2388 patients treated with aHCT over a period of 20 years at a single institution. A total of 1054 deaths (44% of the cohort) were observed: 78% attributed to recurrent disease; 9% to subsequent malignancies and 6% to cardiopulmonary disease. Estimated probability of relative survival was 62% at 5 years and 50% at 10 years from aHCT. On the other hand, the 5-year relative survival was 70, 75, 81 and 88% after having survived 1, 2, 5 and 10 years after aHCT, respectively. The cohort was at a 13.9-fold increased risk of death compared with the general population (95% confidence interval (CI)=13.1-14.8). The risk of death approached that of the general population for 10-year survivors (standardized mortality ratio (SMR)=1.4, 95% CI=0.9-1.9), with the exception of female Hodgkin's lymphoma patients transplanted before 1995 at age 40 years (SMR=6.0, 95% CI=1.9-14.0). Among those who had survived 10 years, nonrelapse-related mortality rates exceeded relapse-related mortality rates. This study provides clinically relevant survival estimates after aHCT, and helps inform interventional strategies.


Asunto(s)
Neoplasias Hematológicas/terapia , Trasplante de Células Madre Hematopoyéticas , Adolescente , Adulto , Anciano , Niño , Femenino , Neoplasias Hematológicas/mortalidad , Humanos , Masculino , Persona de Mediana Edad , Trasplante Autólogo
5.
Clin Ter ; 163(2): 109-13, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22555824

RESUMEN

BACKGROUND AND AIMS: Chronic myeloproliferative diseases (MPDs) are heterogenous group of haematological malignant disorders. It is now a well recognized fact that the JAK2 (V617F) mutation occurs in majority of the patients with polycythaemia vera (PV) and half of those with myelofibrosis and essential thrombocythaemia. The presence of JAK2 (V617F) mutation is considered an important criterion for the exclusion of secondary-reactive from clonal disorders. In the present uni-institutional study, we analyzed the JAK2 (V617F) mutation status in the ethnic Malay and Chinese patients who were diagnosed as MPDs. MATERIALS AND METHODS: The study was performed on known cases of chronic MPDs either at diagnosis or during the follow-up. A total of 45 cases were studied with informed consent. The allele specific PCR, ARMS-PCR and RQ-PCR methods were used. RESULTS: The frequency of the JAK2 (V617F) mutation varied between the MPD subtypes, with the mutation being most frequent in PV (95.8%) and 39% showed homozygous mutant allele. The mutation was detected in 52.9% cases of ET, of which 36.4% were homozygous for the mutant allele and 1 case of MF was homozygous for the mutant allele. CONCLUSION: Screening for the mutation in all cases suspected of chronic MPD could be beneficial in differentiating patients with reactive erthrocytosis or thrombocytosis from the true clonal MPDs especially polycythaemia vera.


Asunto(s)
Janus Quinasa 2/genética , Mutación , Trastornos Mieloproliferativos/genética , Enfermedad Crónica , Femenino , Humanos , Masculino , Persona de Mediana Edad
6.
Malays J Pathol ; 33(2): 95-100, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22299209

RESUMEN

A number of genetic risk factors have been implicated in the development of neonatal severe hyperbilirubinaemia. This includes mutations in the uridine glucoronosyl transferase 1A1 (UGT1A1) gene which is responsible for unconjugated hyperbilirubinemia in Gilbert's Syndrome. We studied the prevalence of UGT1A1 gene mutations in a group of Malay neonates to determine whether they are risk factors to severe neonatal jaundice. One hundred and twenty-five Malay neonates with severe hyperbilirubinemia were studied. Ninety-eight infants without severe hyperbilirubinaemia were randomly selected from healthy Malay term infants (controls). DNA from EDTA cord blood samples were examined for UGT1A1 mutations nt211G > A and nt247T > C using established Taqman SNP genotyping assays and the UGT1A1*28 variant was detected by the Agilent 2100 bioanalyzer. All samples were also screened for common Malay G6PD variants using established techniques. The frequency of UGT1A1 211G > A mutation is significantly higher in the severely hyperbilirubinemic group (13%) than the control group (4%; p = 0.015) and all the positive cases were heterozygous for the mutation. There was no significant difference in the frequency of UGT1A1*28 mutation between the severely hyperbilirubinemic (3.5%) and the control group (0.01%; p = 0.09). None of the neonates in both groups carried the nt247 T > C mutation. The prevalence of G6PD mutation was significantly higher in the severely jaundiced group than control (9% vs 4%; p = 0.04). In conclusion, nt 211 G > A alleles constitute at least 12% of UGT1A1 mutations underlying unconjugated hyperbilirubinemia and appears to be a significant independent risk factor associated with severe neonatal hyperbilirubinemia in the Malay newborns.


Asunto(s)
Predisposición Genética a la Enfermedad/genética , Glucuronosiltransferasa/genética , Hiperbilirrubinemia Neonatal/genética , Ictericia Neonatal/genética , Mutación Puntual , Genotipo , Humanos , Recién Nacido , Malasia , Polimorfismo de Nucleótido Simple , Prevalencia , Reacción en Cadena en Tiempo Real de la Polimerasa
7.
Malays J Pathol ; 33(2): 107-12, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22299211

RESUMEN

Molecular pathogenesis of chronic myeloid leukemia (CML) is well established and molecular monitoring for patients with CML has become an important practice in the management of patients on imatinib therapy. In the present study, we report the use of RQ-PCR method for detection of BCR-ABL fusion gene for our CML cases. We performed a two-step RQ-PCR on bone marrow aspirates or peripheral blood of 37 CML patients. Quantitative expression of BCR-ABL fusion gene was carried out relative to the expression of a housekeeping gene as endogenous control to compensate for uneven cell numbers, RNA quality, or variations in reverse transcription efficiencies. Twenty-four of these patients were pre-treated with hydroxyurea or alpha interferon prior to the imatinib therapy. Their BCR-ABL fusion gene levels were monitored for 18 months. All samples processed were evaluable. The PCR amplification efficiency of the ABL gene is 90.5% (0.2158) and the BCR-ABL gene, 93.4% (0.1573).


Asunto(s)
Proteínas de Fusión bcr-abl/análisis , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Proteínas de Fusión bcr-abl/genética , Humanos , Malasia
8.
East Asian Arch Psychiatry ; 20(4): 163-8, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22348924

RESUMEN

OBJECTIVES: To report the lived experience of caregivers of persons with dementia in Hong Kong, and to explore their service needs. METHODS: This was a qualitative study of caregivers of persons with dementia. Four focus group interviews, each group comprising 6 to 7 informal caregivers, were conducted. A total of 27 participants were recruited. With the participants' consent, interviews were audiotaped and transcribed verbatim. Colaizzi's methods for phenomenological analysis were used. RESULTS: Caregiving in dementia in Hong Kong is as demanding and challenging as reported in other developed communities. 'Confusion regarding diagnosis', 'Emotional impact', 'Difficulty in coping with the care recipient behaviours', 'Provision of care recipient's daily care needs is demanding', and 'Conflicts among social roles' were themes pervasive across every focus group. In addition, the needs of carers changed as the disease of their care recipients progressed. CONCLUSIONS: As the local population continues to age, family caregivers are faced with increasing demands. Understanding their experience is pivotal in the design of effective carer support services. Our findings highlight the sources of strain and unmet needs of Hong Kong Chinese caregivers, which may serve as a guide for future service development.

9.
Ann Acad Med Singap ; 34(8): 499-504, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16205828

RESUMEN

Trauma-Teach is an interactive software for tutoring surgical trainees on medical trauma management procedures. Users of the system interact with a virtual patient suffering from trauma injuries. The task of the user is to stabilise the virtual patient, discover the underlying injuries and decide on an appropriate management plan. Artificial intelligence techniques are used to simulate the patient's pulmonary and cardiovascular systems in real time, determine the responses and results of treatments and diagnostics accordingly, model the patient deterioration if wrong actions are taken, and give a measure of reality to the system by selecting actual trauma cases from the hospital's database.


Asunto(s)
Instrucción por Computador , Programas Informáticos , Traumatología/educación , Inteligencia Artificial , Simulación por Computador
10.
Am J Alzheimers Dis Other Demen ; 16(6): 361-8, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11765861

RESUMEN

Training workshops have been considered a useful intervention in helping family caregivers of people with dementia to cope with the stress of caregiving. However, there are no reports in the literature with regard to training and support of families specifically looking after individuals who are in the late stage of dementia. This paper reports the experience and evaluation of a training workshop aimed at preparing family caregivers for late-stage dementia care. Eighty-eight percent of the participants completed the client satisfaction questionnaire. The results from the questionnaire gave a very positive response, showing 90.9 percent of respondents were satisfied with the workshop, and 77.3 percent of respondents indicated that their caregiving needs were met. Eleven participants who attended this workshop joined a focus group feedback session. The Kruskal-Wallis test found no significant differences between the overall profile of the participants and that of the focus group in terms of age, gender, educational background, whether they were primary caregivers, for whom they cared (e.g., parents or spouse), or whether the care recipient stayed at home or in a nursing home. Findings from the focus group session provide a somewhat different picture from that of the questionnaire. Three focus group participants provided more critical comments of the workshop. Although the majority of the focus group agreed that the workshop had been useful, they disagreed on whether it is necessary to discuss psychosocial issues in this workshop. Findings from the focus group have enabled the project team to reflect on their design and operation of the workshop and provided valuable insight for future development as well as for further study.


Asunto(s)
Enfermedad de Alzheimer/psicología , Cuidadores/psicología , Educación , Enseñanza , Femenino , Humanos , Masculino , Índice de Severidad de la Enfermedad
11.
Cancer ; 86(8): 1528-36, 1999 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-10526282

RESUMEN

BACKGROUND: It is unclear whether blood transfusion can overcome the negative impact of anemia before or during radiotherapy (RT) in patients with carcinoma of the cervix. The objective of this retrospective study was to examine the impact of anemia and blood transfusion on 605 patients with carcinoma of the cervix treated with radical RT at 7 centers across Canada in 1989, 1990, and 1992. METHODS: The data collected included hemoglobin (Hgb) levels from the time of diagnosis to the end of therapy; blood transfusions administered; and identifiable patient-, tumor-, and treatment-related factors. Survival, disease free survival, and pelvic control analyses were evaluated by univariate and multivariate analysis. RESULTS: The median follow-up was 41 months (range, 0-92 months). Presenting Hgb level, average weekly nadir Hgb (AWNH) during RT, and blood transfusion were correlated significantly with local control, disease free survival, and overall survival on univariate analysis. However, the AWNH remained significant on multivariate analysis, whereas Hgb at presentation and blood transfusion did not. The 5-year survival was 74% for patients with an AWNH >/= 120 g/L, 52% for patients with AWNH levels 110-119 g/L inclusive, and 45% for patients with AWNH levels < 110 g/L (P < 0.0001). At each Hgb level, patients who were transfused and maintained a specific Hgb level had a survival rate that was not significantly different from patients who were at that level spontaneously. There was a significant reduction in both pelvic and distant recurrence (P < 0.0001 and P < 0.0006, respectively) in patients whose AWNH level during RT was >/= 120 g/L compared with < 120 g/L. A reduction in the rate of distant recurrence was observed in patients with and without pelvic recurrence. CONCLUSIONS: AWNH is highly predictive of outcome for patients treated with RT for carcinoma of the cervix. Blood transfusion appears to overcome the negative prognostic effects of low presenting Hgb levels and AWNH levels.


Asunto(s)
Adenocarcinoma/radioterapia , Carcinoma de Células Escamosas/radioterapia , Hemoglobinas/metabolismo , Neoplasias del Cuello Uterino/radioterapia , Adenocarcinoma/sangre , Adenocarcinoma/terapia , Adulto , Anciano , Anciano de 80 o más Años , Antineoplásicos/uso terapéutico , Transfusión Sanguínea , Carcinoma de Células Escamosas/sangre , Carcinoma de Células Escamosas/terapia , Cisplatino/uso terapéutico , Terapia Combinada , Femenino , Fluorouracilo/uso terapéutico , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Análisis Multivariante , Recurrencia Local de Neoplasia , Estadificación de Neoplasias , Estudios Retrospectivos , Análisis de Supervivencia , Neoplasias del Cuello Uterino/sangre , Neoplasias del Cuello Uterino/terapia
12.
Radiother Oncol ; 51(2): 123-8, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10435802

RESUMEN

BACKGROUND AND PURPOSE: The use of ipsilateral irradiation techniques to treat patients with carcinoma of the tonsil reduces the acute radiation reaction in the contralateral pharynx and late damage to the contralateral salivary tissue. However, this may also spare microscopic disease in apparently uninvolved contralateral lymph nodes. The purpose of this study was to analyse the survival and recurrence rates and sites of recurrance in a group of patients with carcinoma of the tonsil treated with ipsilateral techniques. MATERIALS AND METHODS: Between 1975 and 1993, 271 patients with invasive squamous cell cancer of the tonsil were referred to the Vancouver Cancer Centre (VCC). One hundred and seventy-eight received ipsilateral radiation treatment. Three received surgery only, six post-operative radiation, 12 supportive treatment only and 72 bilateral radiation treatment. In the absence of bilateral neck nodes and extensive lymphodenopathy, field sizes were generally kept small to include the primary tumour and the first echelon of nodes. The most common dose was 60 Gy in 25 daily fractions in 5 weeks (2.4 Gy per day). RESULTS AND DISCUSSION: The disease specific survival for all patients treated by radical radiation treatment was 61% at 5 years. For the 178 patients who received ipsilateral radiation treatment the overall primary tumour control rate by ipsilateral radiation treatment alone was 75% and for T1 and T2 tumours 84%. Eight (7.5%) of 101 of these patients with N0 nodes at presentation and without prior failure at the primary site, developed nodal recurrence (four within the initially radiated high dose volume). Two developed contralateral nodes, and two developed field edge nodal recurrence, one cured by surgery. In 54 patients with N1 disease, five developed nodal recurrence, two within field, two contralateral, one of whom was cured by surgery, and one at field edge. In 23 patients with N2a, N2b or N3 disease node control was achieved from radiation treatment in 11 and two more were cured by surgery. All nodal failures were within the radiated volume. Overall, 10 of the 25 patients with nodal failure were cured by subsequent surgery. CONCLUSIONS: Ipsilateral treatment of patients with carcinoma of the tonsil gives survival results that are at least as good as those reported with bilateral treatment with fewer side effects and a very low risk of failure in the contralateral neck.


Asunto(s)
Carcinoma de Células Escamosas/radioterapia , Neoplasias Tonsilares/radioterapia , Carcinoma de Células Escamosas/mortalidad , Carcinoma de Células Escamosas/cirugía , Terapia Combinada , Fraccionamiento de la Dosis de Radiación , Humanos , Estadificación de Neoplasias , Dosis de Radiación , Traumatismos por Radiación , Radioterapia/efectos adversos , Radioterapia/métodos , Análisis de Supervivencia , Neoplasias Tonsilares/mortalidad , Neoplasias Tonsilares/cirugía
13.
Radiat Res ; 151(6): 736-46, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10360794

RESUMEN

The effects of radiation on the long-term trends of the total serum cholesterol levels of the Hiroshima and Nagasaki atomic bomb survivors were examined using data collected in the Adult Health Study over a 28-year period (1958-1986). The growth-curve method was used to model the longitudinal age-dependent changes in cholesterol levels. For each sex, temporal trends of cholesterol levels were characterized with respect to age, body mass index, city and birth year. We then examined whether the temporal trends differed by radiation dose. We showed that the mean growth curve of cholesterol levels for the irradiated subjects were significantly higher than that for the unirradiated subjects, and that the increase was greater for women than for men. No difference in dose response was detected between Hiroshima and Nagasaki. An increased mean level of cholesterol was evident for irradiated women in general, but a notable increase was apparent in males only for the youngest birth cohort of 1935-1945. The difference in the mean cholesterol levels between the irradiated and unirradiated subjects diminished past 70 years of age. It is not known whether this is due to natural progression or is an artifact of nonrandom variation in the rate of participation in the examinations. The maximum predicted increase at 1 Gy for women occurred at age 52 years for the 1930 cohort: 2.5 mg/dl (95% CI 1.6-3.3 mg/dl) for Hiroshima and 2.3 mg/dl (95% CI 1.5-3.1 mg/dl) for Nagasaki. The corresponding increase for men occurred at age 29 years for the 1940 cohort: 1.6 mg/dl (95% CI 0.4-2.8) for Hiroshima and 1.4 mg/dl (95% CI 0.3-2.6) for Nagasaki. Controlling for cigarette smoking did not alter the dose-response relationship. Although the difference in the mean growth curves of the irradiated and unirradiated groups was statistically significant, there was a considerable overlap in the individual growth curves of the two groups. The significant sex difference and the greater magnitude of radiation effects in women suggest that hormonal changes resulting from radiation exposure, such as accelerated menopause, is an area worth investigating to delineate the mechanisms underlying the increased cholesterol levels of the irradiated female subjects. This increase may also partially explain the increased rate of coronary heart disease seen in the atomic bomb survivors.


Asunto(s)
Colesterol/sangre , Guerra Nuclear , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Índice de Masa Corporal , Relación Dosis-Respuesta en la Radiación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores Sexuales , Fumar/sangre
14.
Manag Care Interface ; 12(2): 83-8, 90, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10346191

RESUMEN

After collaborating with the Centers for Disease Control and Prevention to develop an evidence-based mammography intervention manual, the dissemination of the manual in a managed care setting was assessed. Using qualitative methods (in-depth interviews), factors were examined that motivated use of the manual by the quality improvement units of eight Prudential HealthCare health plans. Seven of the plans implemented more intensive interventions after having received the manual than in the previous year. Factors that facilitated use of the manual and implementation of recommendations included: internal motivation, support of senior level management, adequate resources (time, personnel, and funds) to support interventions, and the organization and content of the manual itself.


Asunto(s)
Adhesión a Directriz , Servicios de Información , Mamografía/estadística & datos numéricos , Programas Controlados de Atención en Salud/normas , Manuales como Asunto , Anciano , Centers for Disease Control and Prevention, U.S. , Medicina Basada en la Evidencia , Femenino , Humanos , Mamografía/normas , Persona de Mediana Edad , Motivación , Garantía de la Calidad de Atención de Salud , Estados Unidos
15.
Oral Oncol ; 35(1): 33-9, 1999 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10211308

RESUMEN

Patients who present with nasopharyngeal carcinoma (NPC) require through oral and dental assessment prior to treatment of the malignancy. We assessed the oral status of 57 consecutive patients with a diagnosis of NPC. In this study, identified risk factors for NPC were seen to be different in Asian versus non-Asian patients. Epstein-Barr virus seropositivity was seen in all Asian patients and in 69% of non-Asian patients (P = 0.00006), and reported alcohol use was greater in the non-Asian patients. In this study it was found that 68% of dentate patients required dental extractions primarily due to periodontal disease. Even in patients who reported receiving regular dental care (28%) extractions prior to radiation therapy were suggested. Oral complications of radiation therapy were reported by 84% of patients, with the most common being xerostomia. Clinical diagnosis of candidiasis (16%), rampant caries (10% of dentate patients) and difficulties with dentures (25% of denture wearers) were noted. In addition to pretreatment assessment, continuing oral and dental management is needed for patients with NPC.


Asunto(s)
Neoplasias Nasofaríngeas/terapia , Enfermedades Dentales/terapia , Adulto , Anciano , Anciano de 80 o más Años , Asia/etnología , Colombia Británica , Candidiasis Bucal/complicaciones , Infecciones por Virus de Epstein-Barr/complicaciones , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedades de la Boca/etiología , Enfermedades de la Boca/terapia , Neoplasias Nasofaríngeas/etnología , Neoplasias Nasofaríngeas/radioterapia , Traumatismos por Radiación/etiología , Traumatismos por Radiación/terapia , Factores de Riesgo
16.
JAMA ; 280(4): 347-55, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9686552

RESUMEN

CONTEXT: High-dose iodine 131 is the treatment of choice in the United States for most adults with hyperthyroid disease. Although there is little evidence to link therapeutic (131)I to the development of cancer, its extensive medical use indicates the need for additional evaluation. OBJECTIVE: To evaluate cancer mortality among hyperthyroid patients, particularly after (131)I treatment. DESIGN: A retrospective cohort study. SETTING: Twenty-five clinics in the United States and 1 clinic in England. PATIENTS: A total of 35 593 hyperthyroid patients treated between 1946 and 1964 in the original Cooperative Thyrotoxicosis Therapy Follow-up Study; 91 % had Graves disease, 79% were female, and 65% were treated with (131)I. MAIN OUTCOME MEASURE: Standardized cancer mortality ratios (SMRs) after 3 treatment modalities for hyperthyroidism. RESULTS: Of the study cohort, 50.5% had died by the end of follow-up in December 1990. The total number of cancer deaths was close to that expected based on mortality rates in the general population (2950 vs 2857.6), but there was a small excess of mortality from cancers of the lung, breast, kidney, and thyroid, and a deficit of deaths from cancers of the uterus and the prostate gland. Patients with toxic nodular goiter had an SMR of 1.16 (95% confidence interval [CI], 1.03-1.30). More than 1 year after treatment, an increased risk of cancer mortality was seen among patients treated exclusively with antithyroid drugs (SMR, 1.31; 95% CI, 1.06-1.60). Radioactive iodine was not linked to total cancer deaths (SMR, 1.02; 95% CI, 0.98-1.07) or to any specific cancer with the exception of thyroid cancer (SMR, 3.94; 95% CI, 2.52-5.86). CONCLUSIONS: Neither hyperthyroidism nor (131)I treatment resulted in a significantly increased risk of total cancer mortality. While there was an elevated risk of thyroid cancer mortality following (131)I treatment, in absolute terms the excess number of deaths was small, and the underlying thyroid disease appeared to play a role. Overall, (131)I appears to be a safe therapy for hyperthyroidism.


Asunto(s)
Hipertiroidismo/complicaciones , Hipertiroidismo/terapia , Radioisótopos de Yodo/uso terapéutico , Neoplasias/complicaciones , Neoplasias/mortalidad , Adulto , Femenino , Estudios de Seguimiento , Humanos , Radioisótopos de Yodo/efectos adversos , Funciones de Verosimilitud , Masculino , Neoplasias/etiología , Neoplasias Inducidas por Radiación/epidemiología , Distribución de Poisson , Estudios Retrospectivos , Riesgo
17.
Cancer ; 83(4): 629-34, 1998 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-9708924

RESUMEN

BACKGROUND: Because malignant transformation of dysplastic oral leukoplakia has been reported in up to 43% of cases, these lesions must be managed. METHODS: This study evaluated the use of topical 1% bleomycin in dimethylsulfoxide for the treatment of dysplastic oral lesions. Bleomycin was applied once daily for 14 consecutive days to lesions of the oral mucosa in 19 patients. Immediate posttreatment biopsies and the clinical response were evaluated and clinical follow-up was conducted for as long as possible. RESULTS: The mean age of the patients at diagnosis was 59.4 years and 74% were tobacco users. Seventy-five percent of patients had resolution of dysplasia at follow-up biopsy, with a mean improvement of two histologic grades of dysplasia after topical chemotherapy. Ninety-four percent of the patients attained at least partial responses. After a mean follow-up period of 3.4 years, 31.6% of patients had no clinically visible lesions and 47.4% of patients had clinically benign lesions of homogeneous leukoplakia or minimal visible leukoplakia. In 2 patients (11%) malignant transformation occurred a mean of 1.75 years after bleomycin treatment. CONCLUSIONS: Topical bleomycin may prevent the potential progression of leukoplakia through dysplasia to carcinoma. Close follow-up of all patients with dysplasia is required.


Asunto(s)
Antibióticos Antineoplásicos/administración & dosificación , Bleomicina/administración & dosificación , Leucoplasia Bucal/tratamiento farmacológico , Lesiones Precancerosas/tratamiento farmacológico , Administración Tópica , Adulto , Anciano , Femenino , Estudios de Seguimiento , Humanos , Leucoplasia Bucal/patología , Masculino , Persona de Mediana Edad , Estudios Prospectivos
18.
JAMA ; 278(15): 1262-7, 1997 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-9333268

RESUMEN

CONTEXT: There is a substantial risk of a second cancer for persons with hereditary retinoblastoma, which is enhanced by radiotherapy. OBJECTIVE: To examine long-term risk of new primary cancers in survivors of childhood retinoblastoma and quantify the role of radiotherapy in sarcoma development. DESIGN: Cohort incidence study of patients with retinoblastoma followed for a median of 20 years, and nested case-control study of a radiation dose-response relationship for bone and soft tissue sarcomas. SETTING/PARTICIPANTS: A total of 1604 patients with retinoblastoma who survived at least 1 year after diagnosis, identified from hospital records in Massachusetts and New York during 1914 to 1984. RESULTS: Incidence of subsequent cancers was statistically significantly elevated only in the 961 patients with hereditary retinoblastoma, in whom 190 cancers were diagnosed, vs 6.3 expected in the general population (relative risk [RR], 30 [95% confidence interval, 26-47]). Cumulative incidence (+/-SE) of a second cancer at 50 years after diagnosis was 51.0% (+/-6.2%) for hereditary retinoblastoma, and 5.0% (+/-3.0%) for nonhereditary retinoblastoma. All 114 sarcomas of diverse histologic types occurred in patients with hereditary retinoblastoma. For soft tissue sarcomas, the RRs showed a stepwise increase at all dose categories, and were statistically significant at 10 to 29.9 Gy and 30 to 59.9 Gy. A radiation risk for all sarcomas combined was evident at doses above 5 Gy, rising to 10.7-fold at doses of 60 Gy or greater (P<.05). CONCLUSIONS: Genetic predisposition has a substantial impact on risk of subsequent cancers in retinoblastoma patients, which is further increased by radiation treatment. A radiation dose-response relationship is demonstrated for all sarcomas and, for the first time in humans, for soft tissue sarcomas. Retinoblastoma patients should be examined for new cancers and followed into later life to determine whether their extraordinary cancer risk extends to common cancers of adulthood.


Asunto(s)
Neoplasias del Ojo/radioterapia , Neoplasias Inducidas por Radiación/epidemiología , Neoplasias Primarias Secundarias/epidemiología , Retinoblastoma/radioterapia , Sarcoma/epidemiología , Adolescente , Adulto , Estudios de Casos y Controles , Niño , Preescolar , Estudios de Cohortes , Relación Dosis-Respuesta en la Radiación , Neoplasias del Ojo/genética , Femenino , Humanos , Incidencia , Lactante , Masculino , Persona de Mediana Edad , Neoplasias Inducidas por Radiación/etiología , Neoplasias Primarias Secundarias/etiología , Dosificación Radioterapéutica , Retinoblastoma/genética , Riesgo , Sarcoma/etiología , Estadística como Asunto , Análisis de Supervivencia , Sobrevivientes , Factores de Tiempo
19.
J Clin Epidemiol ; 50(4): 425-34, 1997 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9179101

RESUMEN

The 28-year follow-up of a Japanese cohort, having collected vast amounts of data collected on total serum cholesterol (TC), provided an exceptional opportunity to examine TC temporal trends. The longitudinal statistical method of growth-curve analysis was used to elucidate the age-related changes in TC levels and to characterize these trends in relation to sex, birth cohort, time period, place of residence, and body mass index (BMI). Japanese TC levels at initial examination were remarkably lower than those in western countries. During the study period from 1958 to 1986, TC levels increased dramatically with age in both sexes. The slope of the cholesterol growth curve was steeper for women than for men, with the difference growing larger after age 40 years. Drastic changes in Japanese behavior and lifestyle, especially westernization of the diet, are thought to have affected the TC values as time-period effects. As a result of this temporal change, which affected different cohorts at different ages, TC values were higher in members of the younger cohort. The increase of the TC values as time-period effects were larger in earlier period than in later period. These time-period effects appeared to be almost similar in men and women. The TC growth curves also varied by city of residence. Subjects in urban areas had higher TC values than subjects in rural areas. Changes associated with BMI from 1958 to 1986 were only partially responsible for the increased steepness of the TC growth curve.


Asunto(s)
Colesterol/sangre , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Índice de Masa Corporal , Femenino , Estudios de Seguimiento , Humanos , Japón , Masculino , Persona de Mediana Edad , Caracteres Sexuales
20.
Am J Epidemiol ; 144(8): 728-33, 1996 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-8857821

RESUMEN

The authors examined risk factors for benign thyroid nodules and their influence on radiation effects among 544 subjects who were exposed to childhood radiation treatment for benign head and neck conditions at a Chicago, Illinois hospital during 1939-1962. In follow-up through 1991, benign thyroid nodules were diagnosed in 131 patients. The risk of benign nodules was elevated in women (relative risk (RR) = 2.2, 95% confidence interval (CI) 1.6-3.2), Jews (RR = 1.7, 95% CI 1.2-2.5), college graduates (RR = 1.8, 95% CI 1.2-2.8), and subjects whose mother had cancer (RR = 1.7, 95% CI 1.2-2.5). There were increasing trends for risk with increasing body mass index in women and decreasing height in men. Risk was increased for women who never married (RR = 3.7, 95% CI 1.6-7.3) or who never had a full-term pregnancy (RR = 2.0, 95% CI 1.1-3.3). A significant radiation dose-response relationship was observed that was not modified by sex, education, Jewish religion, or reproductive factors. The data suggest that there are genetic, life-style (including ascertainment), and hormonal factors associated with the development of benign thyroid nodules.


Asunto(s)
Glándula Tiroides/efectos de la radiación , Nódulo Tiroideo/etiología , Estudios de Cohortes , Relación Dosis-Respuesta en la Radiación , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Distribución de Poisson , Historia Reproductiva , Factores de Riesgo , Factores Socioeconómicos , Nódulo Tiroideo/genética
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