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1.
Ann Oncol ; 24(9): 2329-35, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23661294

RESUMO

BACKGROUND: We measured breast density (BD) on MRI and correlated with endogenous hormonal levels. PATIENTS AND METHODS: Twenty-four premenopausal women received four weekly breast MRI. A blood sample was collected on the same day of MRI. BD was measured using a computer-based algorithm. The generalized estimation equation method was applied to model mean fibroglandular tissue volume (FV) and mean percent density (PD) from predictor variables including estradiol, progesterone, and week during a cycle. RESULTS: In week 3, a borderline significant correlation between estradiol and PD (r = 0.43, P = 0.04), estradiol and FV (r = 0.40, P = 0.05) and between progesterone and FV (r = 0.42, P = 0.04) was noted. The FV and PD measured in weeks 4 and 1 were higher than in weeks 2 and 3, adjusted for variation in endogenous estradiol and progesterone, indicating that the hormone change could not account for the changes in density. No lag effect of endogenous hormone on the change of FV or PD was noted (all P-values > 0.05). CONCLUSIONS: Our results showed that BD is not strongly associated with the endogenous hormone. Their association with breast cancer risk was likely coming from different mechanisms, and they should be considered as independent risk factors.


Assuntos
Neoplasias da Mama/epidemiologia , Mama/citologia , Mama/fisiologia , Estradiol/sangue , Ciclo Menstrual , Progesterona/sangue , Adulto , Feminino , Humanos , Imageamento Tridimensional , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Risco , Adulto Jovem
2.
Br J Cancer ; 108(3): 512-8, 2013 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-23340449

RESUMO

BACKGROUND: The polyamine-inhibitory regimen difluoromethylornithine (DFMO)+sulindac has marked efficacy in preventing metachronous colorectal adenomas. Polyamines are synthesised endogenously and obtained from dietary sources. Here we investigate dietary polyamine intake and outcomes in the DFMO+sulindac colorectal adenoma prevention trial. METHODS: Dietary polyamine data were available for 188 of 267 patients completing the study. Total dietary polyamine content was derived by the sum of dietary putrescine, spermine and spermidine values and categorised into two groups: highest (>75-100%) vs the lower three quartiles (0-25, 25-50 and 50-75%). Baseline tissue polyamine concentration and ODC1 genotype were determined. Logistic regression models were used for risk estimation. RESULTS: A significant interaction was detected between dietary polyamine group and treatment with regard to adenoma recurrence (P=0.012). Significant metachronous adenoma risk reduction was observed after DFMO+sulindac treatment in dietary polyamine quartiles 1-3 (risk ratio (RR) 0.19; 95% confidence interval (CI) 0.08-0.42; P<0.0001) but not in quartile 4 (RR 1.51; 95% CI 0.53-4.29; P=0.44). However, a lower number of events in the placebo group within dietary quartile 4 confound the aforementioned risk estimates. CONCLUSION: These preliminary findings reveal complex relationships between diet and therapeutic prevention, and they support further clinical trial-based investigations where the dietary intervention itself is controlled.


Assuntos
Adenoma/prevenção & controle , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Colorretais/prevenção & controle , Dieta , Recidiva Local de Neoplasia/prevenção & controle , Poliaminas/administração & dosagem , Adenoma/mortalidade , Adenoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Ensaios Clínicos Fase II como Assunto , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Eflornitina/administração & dosagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/patologia , Prognóstico , Sulindaco/administração & dosagem , Taxa de Sobrevida
3.
Int J Lab Hematol ; 30(4): 300-5, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18665827

RESUMO

Hemochromatosis has often been associated with progressive iron overload, but the natural history of iron accumulation in untreated C282Y homozygotes has been reported infrequently. The Hemochromatosis and Iron Overload Screening (HEIRS) Study screened 101 168 primary care participants for iron overload using transferrin saturation, unbound iron-binding capacity, Serum ferritin (SF), and HFE C282Y and H63D genotyping. SF was measured at initial screening (IS) and again when selected participants returned for a clinical examination (CE). The change in SF over the observation period (defined as ferritin rate of change) was analyzed according to age, gender, initial SF, initial SF/age, transferrin saturation, and iron removed by phlebotomy in C282Y homozygotes. Seventy-four male and 133 female untreated C282Y homozygotes were observed over a median of 112 days (34-924 days) between IS and CE. In men, SF increased in 54% and decreased in 46%. In women, SF increased in 50% and decreased in 50%. The significant variables affecting the SF rate were initial log SF (P = 0.0027) and transferrin saturation (P < 0.0001). Male C282Y homozygotes with higher SF rates (n = 27, upper 50th percentile) had significantly greater iron removed by phlebotomy (mean 4.93 g, range 1.0-17 g) than those with lower SF rates (n = 26, lower 50th percentile) (mean 2.6 g, 0.42-7.1, P < 0.05). SF was as likely to decrease as increase in untreated C282Y homozygotes over this relatively brief observation period. Incremental increases in SF are not inevitable in untreated C282Y homozygotes.


Assuntos
Ferritinas/sangue , Hemocromatose/sangue , Hemocromatose/genética , Antígenos de Histocompatibilidade Classe I/genética , Proteínas de Membrana/genética , Polimorfismo de Nucleotídeo Único/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Proteína da Hemocromatose , Homozigoto , Humanos , Ferro/metabolismo , Masculino , Pessoa de Meia-Idade
4.
Clin Genet ; 71(6): 518-29, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17539901

RESUMO

Iron overload phenotypes in persons with and without hemochromatosis are variable. To investigate this further, probands with hemochromatosis or evidence of elevated iron stores and their family members were recruited for a genome-wide linkage scan to identify potential quantitative trait loci (QTL) that contribute to variation in transferrin saturation (TS), unsaturated iron-binding capacity (UIBC), and serum ferritin (SF). Genotyping utilized 402 microsatellite markers with average spacing of 9 cM. A total of 943 individuals, 64% Caucasian, were evaluated from 174 families. After adjusting for age, gender, and race/ethnicity, there was evidence for linkage of UIBC to chromosome 4q logarithm of the odds (LOD) = 2.08, p = 0.001) and of UIBC (LOD = 9.52), TS (LOD = 4.78), and SF (LOD = 2.75) to the chromosome 6p region containing HFE (each p < 0.0001). After adjustments for HFE genotype and other covariates, there was evidence of linkage of SF to chromosome 16p (LOD = 2.63, p = 0.0007) and of UIBC to chromosome 5q (LOD = 2.12, p = 0.002) and to chromosome 17q (LOD = 2.19, p = 0.002). We conclude that these regions should be considered for fine mapping studies to identify QTL that contribute to variation in SF and UIBC.


Assuntos
Testes Genéticos/métodos , Genoma Humano , Hemocromatose/genética , Ferro/metabolismo , Locos de Características Quantitativas , Adulto , Negro ou Afro-Americano/genética , Idoso , Povo Asiático/genética , Feminino , Frequência do Gene , Genótipo , Hemocromatose/etnologia , Hemocromatose/prevenção & controle , Proteína da Hemocromatose , Hispânico ou Latino/genética , Antígenos de Histocompatibilidade Classe I/genética , Humanos , Indígenas Norte-Americanos/genética , Ferro/sangue , Escore Lod , Masculino , Proteínas de Membrana/genética , Pessoa de Meia-Idade , Fenótipo , População Branca/genética
5.
Clin Genet ; 69(1): 48-57, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16451136

RESUMO

We compared initial screening transferrin saturation (TfSat) and serum ferritin (SF) phenotypes and HFE C282Y and H63D genotypes of 645 Native American and 43,453 white Hemochromatosis and Iron Overload Screening Study participants who did not report a previous diagnosis of hemochromatosis or iron overload. Elevated measurements were defined as TfSat >50% in men and >45% in women and SF >300 ng/ml in men and >200 ng/ml in women. Mean TfSat was 31% in Native American men and 32% in white men (p = 0.0337) and 25% in Native American women and 27% in white women (p < 0.0001). Mean SF was 153 microg/l in Native American and 151 microg/l in white men (p = 0.8256); mean SF was 55 microg/l in Native American women and 63 microg/l in white women (p = 0.0015). The C282Y allele frequency was 0.0340 in Native Americans and 0.0683 in whites (p < 0.0001). The H63D allele frequency was 0.1150 in Native Americans and 0.1532 in whites (p = 0.0001). We conclude that the screening TfSat and SF phenotypes of Native Americans are similar to those of whites. The allele frequencies of HFE C282Y and H63D are significantly lower in Native Americans than in whites.


Assuntos
Ferritinas/metabolismo , Hemocromatose/genética , Antígenos de Histocompatibilidade Classe I/genética , Indígenas Norte-Americanos/genética , Sobrecarga de Ferro/genética , Proteínas de Membrana/genética , Transferrina/metabolismo , População Branca/genética , Adulto , Idoso , Feminino , Ferritinas/genética , Frequência do Gene , Genótipo , Hemocromatose/diagnóstico , Hemocromatose/metabolismo , Proteína da Hemocromatose , Humanos , Sobrecarga de Ferro/sangue , Sobrecarga de Ferro/diagnóstico , Masculino , Pessoa de Meia-Idade , Fenótipo , Transferrina/genética
6.
Blood ; 98(8): 2345-51, 2001 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-11588029

RESUMO

In previous analyses of transferrin saturation data in African Americans and Caucasians from the second National Health and Nutrition Examination Survey (NHANES II), subpopulations were found consistent with population genetics for common loci that influence iron metabolism. The goal of this new study was to determine if these transferrin saturation subpopulations have different levels of iron stores. Statistical mixture modeling was applied to transferrin saturation data for African Americans and Caucasians from the third National Health and Nutrition Examination Survey (NHANES III), and then the mean serum ferritin concentrations were determined for the transferrin saturation subpopulations that were identified. After adjustment for diurnal variation, 3 subpopulations of transferrin saturation were identified in each racial group. Satisfying Hardy-Weinberg conditions for major locus effects, in both racial groups the sum of the square roots of the proportion with the lowest mean transferrin saturation and the proportion with the highest mean transferrin saturation was approximately 1. When weighted to reflect the US adult population as a whole, these subpopulations of increasing transferrin saturations had progressively increasing mean age-adjusted serum ferritin concentration values in each ethnic grouping as stratified by sex (trend test, P <.002 for all). These results are consistent with the concept that population transferrin saturation subpopulations reflect different levels of storage iron.


Assuntos
Ferritinas/sangue , Inquéritos Epidemiológicos , Ferro/sangue , Transferrina/metabolismo , Adulto , População Negra , Ritmo Circadiano , Feminino , Ferritinas/genética , Frequência do Gene , Antígenos de Superfície da Hepatite B/sangue , Anticorpos Anti-Hepatite C/sangue , Humanos , Testes de Função Hepática , Masculino , Seleção de Pacientes , Fatores Sexuais , Transferrina/genética , Estados Unidos , População Branca
7.
Breast Cancer Res Treat ; 66(3): 225-37, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11510694

RESUMO

PURPOSE: To determine whether in vitro extreme drug resistance (EDR) assay results for patients with breast carcinoma were associated with clinical outcome after chemotherapy. PATIENTS AND METHODS: EDR assays were performed on tumor tissue obtained from 103 newly diagnosed breast cancer cases. EDR scores of 2 for low, 1 for intermediate, or 0 for extreme drug resistance were determined for each agent tested. In vitro EDR scores for 4-hydroxycyclophosphamide (4HC) and doxorubicin were summed for patients treated with AC, or for 4HC and 5-FU for patients treated with CMF. Treatment selection was blinded to assay results. RESULTS: Median time to progression was significantly shorter for patients with extreme or intermediate in vitro resistance (n = 55, 48 months), compared to patients with low in vitro resistance, (n = 41, 100 months, p = 0.022). Patients demonstrating extreme to intermediate drug resistance also showed poorer survival than the low resistance group (49.5 months vs. not reached, median follow-up 48 months, p =0.011). Summed EDR scores, stage, and number of lymph nodes were significantly associated with survival in univariate and multivariate analysis. Compared to EDR scores of 4, summed EDR scores of 0-1 and summed EDR scores of 2-3 were associated with a relative risk of death of 3.09 (95%, CI 1.05-9.06, Cox proportional hazards model, p = 0.040) and 2.35 (95%, CI 1.07-5.15, Cox proportional hazards model, p = 0.033), respectively. CONCLUSION: Extreme drug resistance testing identified patients with individual patterns of drug resistance prior to therapy. In this cohort of breast cancer patients treated with chemotherapy, summed EDR scores were significantly associated with time to tumor progression and overall survival. EDR results may offer a method for optimizing treatment selection.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Ciclofosfamida/análogos & derivados , Resistencia a Medicamentos Antineoplásicos , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Bioensaio , Estudos de Coortes , Ciclofosfamida/administração & dosagem , Progressão da Doença , Doxorrubicina/administração & dosagem , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Fluoruracila/administração & dosagem , Humanos , Metotrexato/administração & dosagem , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Análise de Sobrevida
8.
Arch Otolaryngol Head Neck Surg ; 127(5): 553-8, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11346432

RESUMO

OBJECTIVES: To determine the effects of long-term, low-dose difluoromethylornithine (DFMO) on audiometric thresholds and distortion product otoacoustic emission (DPOAE) levels in humans. DESIGN: A prospective, randomized, placebo-controlled phase 2 clinical trial of DFMO in participants with a prior adenomatous colonic polyp. SETTING: Academic tertiary care referral center. PARTICIPANTS: One hundred twenty-three volunteer subjects with colorectal polyps and normal hearing for the frequencies 250 through 2000 Hz. INTERVENTIONS: Subjects were randomized to receive placebo or oral DFMO at daily dosages between 0.075 and 0.4 g/m(2) of body surface area for 12 months. OUTCOME MEASURES: Pure-tone audiometric thresholds for the frequencies 250, 500, 1000, 2000, 3000, 4000, 6000, and 8000 Hz and DPOAE levels were measured at baseline and 1, 3, 6, 9, and 12 months after starting treatment with DFMO or placebo and 3 months after cessation of treatment if there was a suggestion of possible changes at the 12-month measurement. RESULTS: At these low dosages, there was little evidence for shifts in auditory pure-tone thresholds, and there were no statistically significant shifts in DPOAE levels. For auditory pure-tone thresholds, there was a subtle, approximately 2- to 3-dB hearing level decrease in hearing sensitivity for the 2 higher DFMO dosages, but only at the 2 lowest frequencies, 250 and 500 Hz. CONCLUSIONS: Administration of low-dose DFMO for 12 months did not produce hearing loss, in contrast to prior studies that used higher dosages.


Assuntos
Antineoplásicos/administração & dosagem , Audiometria de Tons Puros , Limiar Auditivo/efeitos dos fármacos , Surdez/prevenção & controle , Eflornitina/administração & dosagem , Inibidores da Ornitina Descarboxilase , Emissões Otoacústicas Espontâneas/efeitos dos fármacos , Pólipos do Colo/tratamento farmacológico , Neoplasias Colorretais/dietoterapia , Inibidores Enzimáticos/administração & dosagem , Humanos , Estudos Prospectivos
9.
Gastroenterology ; 120(4): 848-56, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11231939

RESUMO

BACKGROUND & AIMS: Colorectal cancer screening beginning at age 50 is recommended for all Americans considered at "average" risk for the development of colorectal cancer. METHODS: We used 1988-1995 California Cancer Registry data to compare the cost-effectiveness of two 35-year colorectal cancer screening interventions among Asians, blacks, Latinos, and Whites. RESULTS: Average annual age-specific colorectal cancer incidence rates were highest in blacks and lowest in Latinos. Screening beginning at age 50 was most cost-effective in blacks and least cost-effective in Latinos (measured as dollars spent per year of life saved), using annual fecal occult blood testing (FOBT) combined with flexible sigmoidoscopy every 5 years and using colonoscopy every 10 years. A 35-year screening program beginning in blacks at age 42, whites at age 44, or Asians at age 46 was more cost-effective than screening Latinos beginning at age 50. CONCLUSIONS: Colorectal cancer screening programs beginning at age 50, using either FOBT and flexible sigmoidoscopy or colonoscopy in each racial or ethnic group, are within the $40,000-$60,000 per year of life saved upper cost limit considered acceptable for preventive strategies. Screening is most cost-effective in blacks because of high age-specific colorectal cancer incidence rates.


Assuntos
Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/etnologia , Programas de Rastreamento/economia , Adulto , Negro ou Afro-Americano , Idoso , Idoso de 80 Anos ou mais , Análise Custo-Benefício , Etnicidade , Humanos , Pessoa de Meia-Idade , Sistema de Registros , Estados Unidos , População Branca
10.
Obstet Gynecol ; 97(4): 555-60, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11275027

RESUMO

OBJECTIVE: To determine if estrogen replacement therapy, in women with a history of endometrial cancer, increases the risk of recurrence or death from that disease. METHODS: Two hundred forty-nine women with surgical stage I, II, and III endometrial cancer were treated between 1984 and 1998; 130 received estrogen replacement after their primary cancer treatments and 49% received progesterone in addition to estrogen. Among this cohort, 75 matched treatment-control pairs were identified. The two groups were matched by using decade of age at diagnosis and stage of disease. Both groups were comparable in terms of parity, grade of tumor, depth of invasion, histology, surgical treatment, lymph node status, postoperative radiation, and concurrent diseases. The outcome events included the number of recurrences and deaths from disease. RESULTS: The hormone users were followed for a mean interval of 83 months (95% confidence interval [CI] 71.0, 91.4) and the nonhormone users were followed for a comparable mean interval of 69 months (CI 59.1, 78.7). There were two recurrences (1%) among the 75 estrogen users compared with 11 (14%) recurrences in the 75 nonhormone users. Hormone users had a statistically significant longer disease-free interval than nonestrogen users (P =.006). CONCLUSION: Estrogen replacement therapy with or without progestins does not appear to increase the rate of recurrence and death among endometrial cancer survivors.


Assuntos
Adenocarcinoma/mortalidade , Neoplasias do Endométrio/mortalidade , Terapia de Reposição de Estrogênios , Estrogênios Conjugados (USP) , Recidiva Local de Neoplasia/mortalidade , Adenocarcinoma/cirurgia , California/epidemiologia , Estudos de Casos e Controles , Estudos de Coortes , Intervalo Livre de Doença , Neoplasias do Endométrio/cirurgia , Feminino , Humanos , Prontuários Médicos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/cirurgia , Estudos Retrospectivos
11.
Clin Cancer Res ; 7(1): 81-8, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11205922

RESUMO

New molecular factors have been characterized that are associated with the prognosis of prostate carcinoma patients, including p53 status and angiogenesis. We reported recently that mutant p53 (mp53) was associated with decreased expression of an endogenous inhibitor of angiogenesis, thrombospondin-1 (TSP-1), and increased microvessel density in melanoma and breast cancer. In this study, we performed a similar analysis on primary prostate carcinoma to determine whether these factors were associated with each other or patient outcomes. Paraffin-embedded specimens of 98 cases of primary prostate carcinoma were obtained and examined to confirm tissue diagnosis and Gleason scores. Carcinoma-specific levels of p53, TSP-1, and tumor angiogenesis were determined using semiquantitative immunohistochemistry (IHC) methods. Acquisition of mp53 was significantly associated with decreased TSP-1 (P = 0.002) and increased angiogenesis (P < 0.0001). An angiogenesis index integrating mp53, TSP-1, and angiogenesis (CD31) scores was found to be an independent predictor of survival in univariate and multivariate analyses that included Gleason score, clinical stage, and patient age. Further validation of the angiogenesis index in prostate carcinoma may provide a new tool to stratify patient risk.


Assuntos
Adenocarcinoma/irrigação sanguínea , Neovascularização Patológica/patologia , Neoplasias da Próstata/irrigação sanguínea , Adenocarcinoma/metabolismo , Adenocarcinoma/cirurgia , Idoso , Biomarcadores Tumorais/metabolismo , Biópsia por Agulha , Progressão da Doença , Humanos , Processamento de Imagem Assistida por Computador , Técnicas Imunoenzimáticas , Masculino , Mutação , Neovascularização Patológica/metabolismo , Neovascularização Patológica/cirurgia , Inclusão em Parafina , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Prostatectomia , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/cirurgia , Estudos Retrospectivos , Análise de Sobrevida , Trombospondina 1/metabolismo , Proteína Supressora de Tumor p53/metabolismo
13.
Can J Urol ; 7(4): 1066-9, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11109076

RESUMO

OBJECTIVE: This retrospective analysis is to determine rates of clinical infection after prostate needle biopsy with four versus six doses of ciprofloxacin to previous literature. MATERIALS AND METHODS: Two groups were treated with pre and post biopsy 500 mg of ciprofloxacin twice daily by either six doses (n=337) or four doses (n=288) with the first dose given 24 or 12 hours prior to the procedure respectively. RESULTS: Six (0.96%) of the 625 patients had symptomatic urinary tract infections with a positive urinalysis and/or culture. One (0.3%) infection occurred among patients receiving six doses of ciprofloxacin, and five infections (1.7%), were identified among four dose patients. Two febrile episodes occurred in the four dose group, one requiring hospitalization. CONCLUSION: A low infection rate associated with prophylactic regimens. Six doses of ciprofloxacin appears more effective than four doses in reducing the clinical and febrile infection rate following ultrasound guided biopsy of the prostate. No obvious financial benefit was observed.


Assuntos
Biópsia por Agulha/efeitos adversos , Ciprofloxacina/administração & dosagem , Próstata/patologia , Infecções Urinárias/tratamento farmacológico , Infecções Urinárias/prevenção & controle , Humanos , Masculino , Razão de Chances , Estudos Retrospectivos
14.
N Engl J Med ; 343(5): 327-31, 2000 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-10922422

RESUMO

BACKGROUND AND METHODS: We tested the usefulness of measuring the hepatic iron concentration to evaluate total body iron stores in patients who had been cured of thalassemia major by bone marrow transplantation and who were undergoing phlebotomy treatment to remove excess iron. RESULTS: We began treatment with phlebotomy a mean (+/-SD) of 4.3+/-2.7 years after transplantation in 48 patients without hepatic cirrhosis. In the group of 25 patients with liver-biopsy samples that were at least 1.0 mg in dry weight, there was a significant correlation between the decrease in the hepatic iron concentration and total body iron stores (r=0.98, P<0.001). Assuming that the hepatic iron concentration is reduced to zero with complete removal of body iron stores during phlebotomy, the amount of total body iron stores (in milligrams per kilogram of body weight) is equivalent to 10.6 times the hepatic iron concentration (in milligrams per gram of liver, dry weight). With the use of this equation, we could reliably estimate total body iron stores as high as 250 mg per kilogram of body weight, with a standard error of less than 7.9. CONCLUSIONS: The hepatic iron concentration is a reliable indicator of total body iron stores in patients with thalassemia major. In patients with transfusion-related iron overload, repeated determinations of the hepatic iron concentration can provide a quantitative means of measuring the long-term iron balance.


Assuntos
Ferro/análise , Fígado/química , Talassemia beta/patologia , Adolescente , Adulto , Biópsia , Transplante de Medula Óssea , Criança , Feminino , Humanos , Modelos Lineares , Masculino , Flebotomia , Talassemia beta/terapia
15.
Hepatology ; 31(5): 1160-4, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10796893

RESUMO

Early diagnosis and treatment of hemochromatosis is essential to prevent organ damage. Screening strategies to detect early hemochromatosis include testing for iron overload and/or genetic testing. Voluntary blood donors numbering 5,211 were screened with unbound iron-binding capacity (UIBC), transferrin saturation (TS), and genetic testing for the C282Y mutation of the HFE gene. The study found 16 C282Y homozygotes (1 in 327), 69 compound heterozygotes, 371 simple heterozygotes, and 4,755 normals. There were 5 men and 11 women homozygotes with a mean age of 42, range 28 to 57. Mean UIBC (24 +/- 7 microL) and TS (48% +/- 17%) in homozygotes were significantly different from compound heterozygotes, simple heterozygotes, and normals (ANOVA). Only 3 homozygotes had an elevated serum ferritin. Family studies found an additional 4 iron-loaded homozygotes. Optimal thresholds were < or =28 micromol/L for UIBC and > or =46% for TS. Receiver operating characteristic (ROC) curve analysis showed an area under the curve for UIBC of 0.93 (0. 85-1.0, 95% confidence interval), and for TS of 0.83 (0.7-0.95). Screening with UIBC to preselect those for genotyping is a cost-efficient strategy for population screening for hemochromatosis.


Assuntos
Doadores de Sangue , Antígenos HLA/genética , Hemocromatose/diagnóstico , Antígenos de Histocompatibilidade Classe I/genética , Ferro/metabolismo , Proteínas de Membrana , Transferrina/metabolismo , Adulto , Análise Custo-Benefício , Feminino , Genótipo , Hemocromatose/genética , Hemocromatose/metabolismo , Proteína da Hemocromatose , Humanos , Masculino , Pessoa de Meia-Idade
16.
Cancer Epidemiol Biomarkers Prev ; 9(1): 43-7, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10667462

RESUMO

The Bowman-Birk inhibitor (BBI) is a soybean-derived serine protease inhibitor and a potential cancer chemopreventive agent for humans. In this Phase I clinical trial, BBI concentrate was administered as a single oral dose to 24 subjects with oral leukoplakia. Pharmacokinetics of BBI was analyzed, and subjects were monitored clinically for toxic effects. Subjects received between 25 and 800 chymotrypsin inhibitor units (CIU) of the compound in a dose escalation trial. BBI was taken up rapidly, and a metabolic product of BBI was excreted in the urine within 24-48 h. No clinical or laboratory evidence of toxicity was observed in the study. Protease activity was also measured in buccal cells to evaluate usefulness as a biomarker. Single-dose BBI concentrate administered up to 800 CIU was well tolerated and appeared to be nontoxic. Further investigation in Phase II clinical trials is being done.


Assuntos
Anticarcinógenos/uso terapêutico , Leucoplasia Oral/tratamento farmacológico , Inibidor da Tripsina de Soja de Bowman-Birk/uso terapêutico , Inibidores da Tripsina/uso terapêutico , Administração Oral , Idoso , Anticarcinógenos/administração & dosagem , Anticarcinógenos/efeitos adversos , Anticarcinógenos/farmacocinética , Anticarcinógenos/urina , Biomarcadores/análise , Quimioprevenção , Quimotripsina/antagonistas & inibidores , Endopeptidases/análise , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Mucosa Bucal/enzimologia , Inibidor da Tripsina de Soja de Bowman-Birk/administração & dosagem , Inibidor da Tripsina de Soja de Bowman-Birk/efeitos adversos , Inibidor da Tripsina de Soja de Bowman-Birk/farmacocinética , Inibidor da Tripsina de Soja de Bowman-Birk/urina , Inibidores da Tripsina/administração & dosagem , Inibidores da Tripsina/efeitos adversos , Inibidores da Tripsina/farmacocinética , Inibidores da Tripsina/urina
17.
Stat Med ; 19(1): 83-98, 2000 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-10623915

RESUMO

Automated storage and analysis of the results of serial haematologic studies are now technically feasible with present-day laboratory instruments and devices for data storage and processing. In current practice, physicians mentally compare a laboratory result with previous values and use their clinical judgement to determine the significance of any change. To provide a statistical basis for this process, we describe a new approach for the detection of changes in patient-specific sequential measurements of standard haematologic laboratory tests. These methods include hierarchical multiple regression modelling, with a weighted minimum risk criteria for model selection, to choose models indicating changes in mean values over time. This study is the first to analyse sequential patient-specific distributions of laboratory measurements, utilizing mixture distribution modelling with systematic selection of starting values for the EM algorithm. To evaluate these statistical methods under controlled conditions, we studied 11 healthy human volunteers who were depleted of iron by serial phlebotomy to iron-deficiency anaemia, then treated with oral iron supplements to replete iron stores and correct the anaemia. Application of sequential patient-specific analyses of haemoglobin, haematocrit, and mean cell volume showed that significant departures from past values could be identified, in many cases, even when values were still within the population reference ranges. Additionally, for all subjects sequential alterations in red blood cell volume distributions during development of iron-deficiency anaemia could be characterized and quantified. These methods promise to provide more sensitive techniques for improved diagnostic evaluation of developing anaemia and serial monitoring of response to therapy.


Assuntos
Testes Hematológicos , Modelos Lineares , Distribuições Estatísticas , Administração Oral , Algoritmos , Anemia Ferropriva/diagnóstico , Anemia Ferropriva/tratamento farmacológico , Contagem de Células Sanguíneas , Índices de Eritrócitos , Feminino , Hematócrito , Humanos , Ferro/administração & dosagem , Masculino
18.
Blood Cells Mol Dis ; 25(2): 130-8, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10389595

RESUMO

The major elements of bone pathology in Gaucher disease are a failure of osteoclast and osteoblast function, resulting in osteopenia and also osteonecrosis. T lymphocytes have recently been found to be involved in the regulation of osteoblast/osteoclast activity in vitro. In the present report the peripheral blood T major lymphocyte subsets were investigated in a group of genotyped type 1 Gaucher disease patients. A total of 31 patients were studied: 21 non-splenectomized (5 N370S homozygotes) and 10 splenectomized (of whom 1 was a N370S homozygote). The results show that non-splenectomized patients present a decrease in absolute numbers of peripheral blood T lymphocytes, specially the CD4+ T subset. However, when patients were analyzed with respect to the presence of bone disease, the number of CD8+ T lymphocytes was found to be statistically significantly lower in patients presenting bone involvement. Furthermore, lower numbers of CD8+ T lymphocytes were significantly correlated with higher levels of plasma tartrate resistant acid phosphatase (TRAP) activity, a putative marker of osteoclast cell activity. These in vivo findings are in agreement with the results reached in vitro by others. They provide an additional marker of disease severity in Gaucher disease. In the group of genotyped Gaucher disease patients, the majority of the N370S homozygous patients presented a clinically milder phenotype, including the absence of bone involvement, confirming earlier reports predicting that a number of these patients may remain undiagnosed. Collectively the homozygosity for the N370S mutation and normal T cell numbers may provide additional markers for the clinical heterogeneity of Gaucher disease.


Assuntos
Doenças Ósseas/sangue , Doença de Gaucher/sangue , Linfócitos T/citologia , Fosfatase Ácida/sangue , Fosfatase Ácida/efeitos dos fármacos , Adolescente , Adulto , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD8-Positivos/citologia , Criança , Feminino , Doença de Gaucher/tratamento farmacológico , Doença de Gaucher/genética , Genótipo , Glucosilceramidase/uso terapêutico , Humanos , Isoenzimas/sangue , Isoenzimas/efeitos dos fármacos , Contagem de Linfócitos/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes/uso terapêutico , Esplenectomia , Fosfatase Ácida Resistente a Tartarato
20.
Trans R Soc Trop Med Hyg ; 92(3): 325-31, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9861410

RESUMO

The majority of deaths from cerebral malaria occur within 48 h after admission to hospital. Because of the possibility of inadequate treatment within this period, the use of a loading dose of quinine has been proposed. We reviewed clinical and laboratory data for 113 children with cerebral malaria, who were treated with intravenous quinine, 10 mg/kg every 8 h, at Macha Mission Hospital in rural Zambia. In 1990-1991, 39 children were not given a loading dose of quinine while, in 1992-1993, 74 children received a loading dose of 20 mg/kg. Elevated serum iron levels, as reflected in transferrin saturation, were strongly associated with higher mortality. A loading dose of quinine was associated with faster recovery from coma and enhanced clearance of parasitaemia and fever. The loading dose was also associated with trends to lower mortality and higher haemoglobin levels, but these differences were not statistically significant.


Assuntos
Antimaláricos/administração & dosagem , Malária Cerebral/tratamento farmacológico , Quinina/administração & dosagem , Anemia Ferropriva/tratamento farmacológico , Animais , Pré-Escolar , Coma/tratamento farmacológico , Método Duplo-Cego , Feminino , Febre/tratamento farmacológico , Hemoglobina A/análise , Humanos , Malária Cerebral/sangue , Malária Cerebral/mortalidade , Masculino , Saúde da População Rural , Transferrina/análise , Zâmbia/epidemiologia
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