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S Kaba

Publications and source records attributed to S Kaba.

16 recordsLinked to original sources
PubMed2001

Association between polymorphisms of folate- and methionine-metabolizing enzymes and susceptibility to malignant lymphoma.

Genetic alteration is considered a probable cause of malignant lymphoma. Folate and methionine metabolism play essential roles in DNA synthesis and DNA methylation, and their metabolic pathways might thus affect disease susceptibility. In the present study, 2 polymorphisms were evaluated for a folate metabolic enzyme, methylenetetrahydrofolate reductase (MTHFR), and one was evaluated for methionine synthase (MS). The 2 polymorphisms, MTHFR677 C-->T and MTHFR1298 A-->C, are reported to reduce the enzyme activity, which causes intracellular accumulation of 5,10-methylenetetrahydrofolate and results in a reduced incidence of DNA double-strand breakage. The MS2756 A-->G polymorphism also reduces the enzyme activity and results in the hypomethylation of DNA. To evaluate the association between malignant lymphoma susceptibility and these polymorphisms, hospital-based case-control study was conducted in Aichi Cancer Center. Ninety-eight patients with histologically confirmed lymphoma and 243 control subjects without cancer were evaluated. Unconditional logistic regression analyses revealed a higher susceptibility with the MTHFR677 CC and the MTHFR1298 AA genotypes (odds ratio, 2.26; 95% confidence interval, 1.26-4.02) when those harboring at least one variant allele in either polymorphism of MTHFR were defined as the reference. For the MS polymorphism, the MS2756 GG genotype also showed a higher susceptibility (odds ratio, 3.83; 95% CI, 1.21-12.1) than those with MS2756 AA or AG types. The significance was not altered when these 3 polymorphisms were evaluated in combination, and the results suggest that folate and methionine metabolism play important roles in the occurrence of malignant lymphomas. Further studies to confirm the association and detailed biologic mechanisms are now required.

5-Methyltetrahydrofolate-Homocysteine S-Methyltran↗
PubMed2000

Which patients with hepatitis C develop liver complications?

To identify variables that are independent predictors of adverse outcomes in chronic hepatitis C, we analyzed a cohort of 455 patients followed for a median of 4.7 years. Associations were sought between demographic and behavioral factors, hepatitis C virus (HCV) genotype, liver histology and liver tests at entry, and development of liver complications, hepatocellular carcinoma (HCC), hepatic transplantation and liver-related death. Independent predictors were identified by multivariate analysis. The following were associated with a significantly higher rate of liver complications: age; birth in Asia, Europe, Mediterranean region, or Egypt; transmission by blood transfusion or sporadic cases; HCV genotypes 1b and 4 (compared with 1/1a); fibrosis stage 3 or 4 (cirrhosis); serum albumin; bilirubin; prothrombin time; and alpha-fetoprotein. However, the only independent predictors of liver-related complications were sporadic transmission (P <.001), advanced fibrosis (P =.004), and low albumin (P <.001). The corresponding independent risk factors for HCC were male gender (P =. 07), sporadic transmission (P <.001), and albumin (P <.001); bilirubin (P =.02) was an additional predictor of transplantation or liver-related death. It is concluded that only patients with advanced hepatic fibrosis or cirrhosis, are at risk of developing hepatic complications of chronic hepatitis C during 5-year follow-up. Among such patients, abnormalities in serum albumin, bilirubin, or prothrombin time indicate a high probability of complications. Patients without definite risk factors for HCV (sporadic cases) are at higher risk of complications, possibly because of interaction between older age, duration of infection, country of birth, and HCV genotypes 1b and 4.

Adult↗
PubMed1998

Endometrial cytology in postmenopausal hormone replacement therapy.

Endometrial changes is postmenopausal hormone replacement therapy (HRT) were studied by comparing cytological and histological findings. Cytological and histological examinations were conducted on 138 benign cases and 26 abnormal cases, including 24 cases with disordered proliferative phase (DOP) and 2 cases with simple endometrial hyperplasia (SEH), for a total of 164 cases. Hormones were administered as follows: 1) single cyclic administration of estrogen only (Single-HRT) for 31 cases, 2) cyclic administration of estrogen and progestin (Cyclic-HRT) for 105 cases, and 3) continuous administration of estrogen and progestin (Continuous-HRT) for 28 cases. All of the 164 cases were studied cytologically as to shape, appearance, nuclear number on maximum diameter, and so on. The benign cases in each mode of administration as described above revealed the following: 1) Single-HRT, atrophy or the proliferative phase was noted histologically, and the copresence of the endometrial epithelium and the ciliated cell metaplasia was observed cytologically; 2) Cyclic-HRT, the first half of the administration term was of the proliferative phase histologically, and the linear and long glands were seen cytologically. In the latter half of the administration term the secretory phase was noted histologically and the curved/linear glands with subnuclear vacuolization were observed cytologically; and 3) Continuous-HRT, atrophy was noted histologically, and fewer glands and atrophic cells on the endometrial epithelium with wrinkles mixed therein were seen cytologically. On the other hand, cytological examinations of the abnormal cases revealed a mean average of 35 nuclei on the maximum diameter of the gland, protrusion and/or ramification of the glands, densely clustered glands, and back-to-back glands without fusion, as well as irregularly dilated tortuous glands in SEH. These abnormal findings were considered useful for early detection of endometrial disorders in the hormone replacement therapy by cytodiagnosis.

Adult↗
PubMed1998

Effects of hepatitis G virus coinfection on severity of hepatitis C: relationship to risk factors and response to interferon treatment.

The aims of the present study were to identify characteristics that are more often associated with hepatitis G virus (HGV) coinfection in Australian patients infected with the hepatitis C virus (HCV) and to investigate the effects of HGV on the histological and functional severity of chronic hepatitis C. Serum samples from 209 patients with chronic hepatitis C were tested for HGV-RNA using single-round reverse transcriptase-polymerase chain reaction to primers directed at the NS5 region of the HGV genome. Hepatitis G virus RNA was detected in 40 cases (19%). Hepatitis G virus-coinfected patients tended to be younger and parenteral risks could be identified in all but six. Although country of birth did not differ significantly between the coinfected and HCV-alone groups, HGV-positive patients appeared to be less likely to have originated from Asia. On logistic regression analysis, HCV genotype 3a was found in a significantly higher proportion of patients with HGV coinfection than other genotypes (P < 0.01). Liver histology and response to interferon were similar in the HGV-coinfected and HCV-alone groups and liver-related complications appeared to occur less frequently in patients with both HGV and HCV. On univariate analysis, antipyrine clearance was found to be higher in the coinfected group (P < 0.05), implying better preservation of hepatic metabolic function, but this difference was lost when adjusted for HCV genotype. In conclusion, coinfection with HGV was more commonly associated with HCV genotype 3a, a genotype associated with injection drug use in younger patients. However, the presence of HGV coinfection did not adversely affect liver disease or the response to interferon treatment in patients with chronic hepatitis C.

Adult↗
PubMed1998

Molecular epidemiology of hepatitis C in Australia.

The aim of this study was to determine the distribution of hepatitis C virus (HCV) genotypes in Australian patients with hepatitis C and to identify factors associated with particular genotypes. Serum isolates of HCV-RNA were genotyped using a commercial oligonucleotide hybridization (line probe) assay. Relationships between demographic factors, mode of HCV transmission and HCV genotype were assessed by logistic regression analysis. Among 463 patients with hepatitis C, 425 tested positive for HCV-RNA and a single HCV genotype was identified in 420 cases. The patients' places of birth were Australia or New Zealand (62%), Asia (13%), Europe (12%), Mediterranean (6%), Middle East (6%) and other countries (< 1%). The most common genotypes were type 1 (52%) or type 3 (32%); type 2 (9.3%), type 4 (5.5%) and type 6 (1.7%) were less common. Patients with genotype 1b were older (48 +/- 13 years, P< 0.001) and patients with genotype 3 were younger than the remaining patients (37 +/- 11 years vs 42 +/- 12 years, P< 0.001). Among type 1 isolates, 1b was more common for patients born outside Australia compared with those born in Australia (50% vs 13%, P< 0.001) whereas non-1b subtypes were more common among Australian-born patients. Likewise, 21 of 23 (91%) patients with type 4 were from Egypt and six of seven (86%) with type 6 were from Vietnam. The relative importance of parenteral risk factors for HCV also varied according to geographic origin. Thus, a definite risk factor for HCV acquisition was identified in > 95% of Australian-born patients, but in only 33% of Asian or Mediterranean-born patients. Logistic regression analysis indicated that region of birth and risk factor (intravenous drug use or not) would allow 98% of type 4 cases and 76% of type 1b cases to be identified correctly. In summary, region of birth, patterns of migration over time and risk factors for transmission of HCV interact to determine the distribution of HCV genotypes in a multi-racial community like Australia.

Adult↗
PubMed1994

The lesion causing continuous facial myokymia in multiple sclerosis.

OBJECTIVE: To attempt to identify the site of the lesion causing continuous facial myokymia (CFM) in multiple sclerosis (MS) through the use of magnetic resonance imaging (MRI). DESIGN: A case series was employed. SETTING: The Baird Multiple Sclerosis Center, Millard Fillmore Hospital, and the Neurology Department, Buffalo General Hospital, Buffalo, NY. PARTICIPANTS AND MEASURES: Twelve patients with MS and CFM were examined by MRI of the brain while the CFM was present. The MRI examinations were also performed before the CFM had developed and after it had ceased in eight of the patients. Another 57 patients with MS who never had CFM but who had similar disabilities to those who did were also examined by MRI. RESULTS: In 11 of the 12 patients with MS and CFM, the causative lesion was demonstrated to involve the postnuclear, postgenu portion of the facial nerve intraaxially in the dorsolateral pontine tegmentum ipsilateral to the CFM. In the majority of patients who were studied after the CFM had stopped clinically, the lesion was observed to resolve on MRI. Seventeen percent of the patients with MS but without CFM were found to have the typical pontine tegmental lesion. CONCLUSIONS: Continuous facial myokymia in MS is caused by a pontine tegmental lesion involving the postnuclear, postgenu portion of the facial nerve. The lesion is identified by MRI in approximately 90% of patients with MS who have CFM clinically. The typical MRI lesion may also be found in a minority of patients with MS who do not have CFM clinically.

Adult↗
PubMed1993

Imprint cytology of low-grade B-cell lymphoma of mucosa-associated lymphoid tissue arising in the thymus: a case report.

Low-grade B-cell lymphoma of mucosa-associated lymphoid tissue (MALT) arising in the thymus is a very rare tumor with characteristic morphologic features. We describe a case of thymic low-grade B-cell MALT lymphoma occurring in a 59-yr-old woman with Sjögren's syndrome, in whom the definite diagnosis was difficult at the time of surgery. An immunohistologic and genotypic study, however, was diagnostic of lymphoma. A review of cytologic material was undertaken, and it was felt that the cytologic features in Giemsa-stained preparations in imprint smears were present that initially should have enabled the correct cytodiagnosis and distinction from the other thymic lesions. The findings presented in this study were considered to contribute to the cytodiagnosis of a thymic lesion, which might, in the past, have been erroneously interpreted as another lymphoproliferative disorder.

Cytodiagnosis↗
PubMed1993

Circulating CD3+ CD4+ CD8+ T lymphocytes in multiple sclerosis.

Triple-antibody flow cytometry was used to search for distinctive populations of peripheral blood lymphocyte immunophenotypes in multiple sclerosis (MS). Using monoclonal antibodies to the cell surface markers CD3, CD4, and CD8, T cell subsets were quantified on a cohort of 31 MS patients (not treated with corticosteroids for at least 6 months), 30 healthy donors, and 14 patients with other autoimmune diseases (also corticosteroid treatment-free for at least 6 months). Untreated MS patients displayed a significantly greater population of CD3+CD4+CD8+ circulating T cells than healthy donors (P = 0.023). Patients with other autoimmune diseases displayed mean populations of CD3+CD4+CD8+ cells greater than normal donors and less than MS, but not significantly different from either. An additional 45 MS patients who had received corticosteroid therapy within the previous 6 months were phenotyped. Treatment of symptomatic MS with corticosteroids was associated with a smaller population of circulating CD3+CD4+CD8+ cells. Some MS patients have significantly greater numbers of peripheral blood T lymphocytes simultaneously expressing CD3, CD4, and CD8 surface markers than healthy donors and this population of cells may be reduced by corticosteroids treatment. This triple positive phenotype may be a manifestation of a systemic immune abnormality in MS.

Antigens, CD↗
PubMed1988

[Morphometrical study on prognosis of stage I pulmonary adenocarcinoma].

The prognostic significance of morphometry in stage I pulmonary adenocarcinoma had been examined in Papanicolaou-stained bronchial brushings, using an image analyzer. The data of long-term survivors (LTS), alive for more than 5 years, and short-term survivors (STS), who had died within 5 years, were compared. LTS were found to have a smaller nuclear area, a shorter nuclear perimeter, and a smaller nucleolar area than those of the STS. The nuclear size is considered important in any histological subtypes. The variation index of the nuclear area, the nuclear circularity, and the number of nucleoli did not differ between the two groups. These results would seem to be useful in determining the prognosis and the indication type of adjuvant therapy to be used in surgical operations.

Adenocarcinoma↗
PubMed1988

[Malaria and pregnancy. Epidemiological situation in Kinshasa (Zaïre)].

By regular blood smears to 730 women (430 pregnant women and 250 non pregnant) authors state precisely epidemiologic situation of malaria to women at Kinshasa. The prevalence of malaria of pregnant women is 22 per cent against 6.1 per cent for non pregnant adult women. Malarial infestation in gravido-puerperal period is : mother : 23.7 per cent ; umbilical cord : 3.1 per cent ; newborn : 5.4 per cent ; placenta : 10.1 per cent. Plasmodium falciparum is the principal agent of malaria at Kinshasa. Neither age, nor parity constitute risk factors of malaria. Many cases of malaria without fever exist at Kinshasa. Newborn with malaria and from pregnancies with infected placentas present at the birth a small weight. Placentas of pregnancies with malaria and infected have invariably the same weight.

Adult↗