Biomedical subjects

Tomoko Sonoda

Publications and source records attributed to Tomoko Sonoda.

At least 19 recordsLinked to original sources

PubMed2007

Identification of DFNA5 as a target of epigenetic inactivation in gastric cancer.

Epigenetic gene inactivation plays a key role in the development of various types of cancer. Using methylated CpG island amplification coupled with representational difference analysis to identify genes inactivated by DNA methylation in gastric cancer, we identified seven DNA fragments corresponding to the 5' CpG islands of the affected genes. One of the clones recovered was identical to the 5' flanking region of DFNA5, a gene previously shown to be associated with deafness and induced by DNA damage. Further analysis revealed that DFNA5 is expressed in normal tissues but is down-regulated in gastric cancer cell lines due to methylation of the region around its transcription start site. Treating gastric cancer cells that lacked DFNA5 expression with a methyltransferase inhibitor, 5-aza-2'-deoxycytidine, restored the gene's expression. Methylation of DFNA5 was detected in 50% of primary gastric tumors, and was correlated with positivity for Epstein-Barr virus and the absence of metastasis. Moreover, introduction of exogenous DFNA5 into silenced cells suppressed colony formation. Taken together, these data suggest that the silencing of DFNA5 occurs frequently in gastric cancer and may play a key role in development and progression of the disease.

Aged↗

PubMed2006

Binding of glutamate receptor delta2 to its scaffold protein, Delphilin, is regulated by PKA.

The glutamate receptor delta2 (GluRdelta2) is selectively expressed in cerebellar Purkinje cells and plays an important role in motor learning, motor coordination, and long-term depression. Delphilin is identified as a GluRdelta2-interacting protein, selectively expressed in Purkinje cell-parallel fiber synapses, and specifically interacts with the GluRdelta2 C-terminus via its PDZ domain. Here, surface plasmon resonance analyses showed that Delphilin PDZ bound to GluRdelta2 C-terminal peptide (DPDRGTSI), but not to its phosphopeptides (DPDRGphosphoTSI and DPDRGTphosphoSI). We showed the incorporation of phosphate into threonine at -2 (-2T) and serine at -1 (-1S) of GluRdelta2 C-terminus by cAMP-dependent protein kinase (PKA) in vitro. In the experiments using heterologous expression system, Delphilin coimmunoprecipitated with GluRdelta2 was dramatically decreased under the condition with forskolin and isobutylmethylxanthine, which led to cAMP-dependent phosphorylation by PKA. Thus, phosphorylation of -2T and/or -1S of GluRdelta2 C-terminus by PKA may regulate the binding of GluRdelta2 to its scaffolding protein, Delphilin.

Binding Sites↗

PubMed2006

Abnormal spermatogenesis in mice unable to synthesize ascorbic acid.

Although exposure to environmental toxicants, including endocrine-disrupting chemicals, is thought to be a possible cause of male infertility, the pathogenesis of male reproductive disorders remains unclear. In the present study, we used Gulo-/- mutant mice, which are unable to synthesize ascorbic acid, to study the importance of dietary vitamin C (VC) on spermatogenesis. Regular chow containing approximately 110 mg/kg VC is unable to support the growth of these mutant mice, but a VC supplement in their drinking water (330 mg/L) is able to ameliorate the VC deficiency. Testes of Gulo-/- mutants born from heterozygous mothers without VC supplement (VC-deficient mice) and those born from mothers given a VC supplement (VC-sufficient mice) were examined by morphological and biochemical analyses. Morphological analysis revealed that apoptosis of spermatocytes occurred frequently in VC-deficient mice at 20 days of age. Two-dimensional electrophoresis analysis revealed the specific disappearance of heat-shock protein (Hsp) 70 in the testes of 20-day-old VC-deficient mice. In the present study, the relationship between the apoptosis of spermatocytes and Hsp70 in VC-deficient mice is discussed.

Animals↗

PubMed2005

Identification and characterization of a novel Delphilin variant with an alternative N-terminus.

Delphilin is identified as a Glutamate receptor delta2 (GluRdelta2) subunit interacting protein, consisting of a PDZ domain and formin homology (FH) domains 1 and 2, in addition to a C-terminal coiled-coil structure. Delphilin has been shown to be selectively expressed in cerebellar Purkinje cells where it co-localizes with the GluRdelta2 subunit at the Purkinje cell-parallel fiber synapses. Although Delphilin specifically interacts with the GluRdelta2 C-terminus via its PDZ domain, the physiological role of the interaction is not yet understood. Here, we report that the Delphilin protein exhibits diversity at its N-terminus by variable usage of the first several exons. Interestingly, the two Delphilin mRNAs which correspond to the first one initially identified (now designated as Delphilin alpha) and the second that contains a newly identified first exon (designated as Delphilin beta), show different chronological expression profiles. Delphilin beta mRNA was not decreased throughout the cerebellar development in vivo and in vitro, while in vivo Delphilin alpha mRNA gradually decreases following the first postnatal week. Delphilins alpha and beta also revealed different subcellular distribution with some overlap. Specifically, the cerebellar synaptosomal membrane fraction contained the Delphilin beta protein. Both Delphilin alpha and beta localized at the dendritic spines with GluRdelta2; however, dendritic shafts in cultured Purkinje cells also included Delphilin beta. In MDCK cells upon becoming confluent, Delphilin alpha moved to the cell-cell junction area, whereas Delphilin beta maintained a diffuse distribution pattern throughout the cytoplasm. Taken as a whole, these two different Delphilins seemed to play functionally different roles in developing and matured cerebellar Purkinje cells.

Alternative Splicing↗

PubMed2005

[Depressive symptomatology and some relevant factors. Investigations at a junior college in Hokkaido, Japan].

PURPOSES: Recently in Japan, major depression, a depressive state, and suicide are increasingly becoming social problems requiring preventive intervention. However, only few investigations have been performed of actual conditions of mental health. The present study was therefore planned and carried out to examine relations between stress and relevant factors in adolescents and to search for clues for preventive intervention. METHODS: A total of 184 students in a junior college in Hokkaido were the subjects of this cross-sectional survey. In October 2003, age, sex, health-related factors, social supports, stressors, loci of control, coping styles, and depressive status were investigated. After excluding data from incomplete responses, we ultimately analyzed 153 students (mean age = 19.9, 141 females). RESULTS: Regardless of the CES-D categorization, after conducting univariate logistic regression analysis, we found that cognitive style and consciousness of stress were significantly associated with depressive symptomatology. The association remained significant even after multivariate logistic regression analysis. CONCLUSIONS: Cognitive style may influence depression in adolescents. We now need to consider preventive interventions applying the theory of cognitive-behavioral therapy.

Adolescent↗

PubMed2004

Genome-wide linkage analysis of type 2 diabetes mellitus reconfirms the susceptibility locus on 11p13-p12 in Japanese.

Type 2 diabetes mellitus is a heterogeneous disorder, and the development of type 2 diabetes mellitus is associated with both insulin secretion defect and insulin resistance. The primary metabolic defect leading to type 2 diabetes mellitus has been thought to be varied among populations, especially in Japanese and Caucasians. Here, we have done the genome-wide scan for type 2 diabetes mellitus using 102 affected Japanese sib-pairs to identify the genetic factors predisposing to type 2 diabetes mellitus. Nonparametric linkage analysis showed one suggestive evidence for linkage to 11p13-p12 [D11S905: two-point maximum LOD score (MLS) of 2.89 and multipoint MLS of 2.32] and one nominally significant evidence for linkage to 6q15-q16 (D6S462: two-point MLS of 2.02). Interestingly, the 11p13-p12 region was reported to be a susceptibility locus for Japanese type 2 diabetes mellitus with suggestive evidence of linkage, and D11S905 was within 5 cM to D11S935 with the highest MLS in the previous linkage analysis reported. The only overlapped susceptibility region with suggestive evidence of linkage for Japanese type 2 diabetes mellitus was D11S935-D11S905 among the three reports including this study. These results taken together suggest that a susceptibility gene for type 2 diabetes mellitus in Japanese will reside in 11p13-p12.

Chromosomes, Human, Pair 11↗

PubMed2004

Impact of health education and screening over all-cause mortality in Japan: evidence from a cohort study during 1984-2002.

BACKGROUND: Health education and screening are two components of preventive health services in Japan since 1983. This study investigated their relationships with all-cause mortality as they are studied insufficiently in Hokkaido, Japan. METHODS: This study enrolled 1,532 men and 1,653 women aged 40-97 years from 1,702 randomly selected households of 60 areas during 1984-1985 and followed them until 2002. At baseline survey, staffs of 45 health centers collected sociodemographic, medical, behavioral, and dietary information including health education and screening from study subjects with informed consent. RESULTS: For men, age-adjusted Cox proportional hazard model indicated lower mortality for those who received health education (RR = 0.76, P < 0.01) and screening (RR = 0.83, P < 0.05) than those who did not. Health education showed lower mortality even after adjusting for many variables. Similarly for women, health education (RR = 0.66, P < 0.01) and screening (RR = 0.64, P < 0.001) revealed lower age-adjusted mortality. Almost similar results were found for both services when models were adjusted for many variables and when the deaths including lost to follow-up cases of the first 4 years of baseline survey are excluded. CONCLUSIONS: This study shows protective effects of health education and screening over all-cause mortality for both sexes. However, further studies are needed to confirm the results.

Adult↗

PubMed2004

A case-control study of diet and prostate cancer in Japan: possible protective effect of traditional Japanese diet.

The age-adjusted incidence of prostate cancer is low in Japan, and it has been suggested that the traditional Japanese diet, which includes many soy products, plays a preventive role against prostate cancer. We performed a case-control study on dietary factors and prostate cancer in order to assess the hypothesis that the traditional Japanese diet reduces the risk of prostate cancer. Four geographical areas (Ibaraki, Fukuoka, Nara, and Hokkaido) of Japan were selected for the survey. Average daily intake of food from 5 years before the diagnosis was measured by means of a semi-quantitative food frequency questionnaire. We studied 140 cases and 140 individually age ( +/- 5 years)-matched hospital controls for analysis. Estimates of age-adjusted odds ratios (ORs) and linear trends were calculated by conditional logistic regression models with adjustment for cigarette smoking and total energy intake as confounding factors. Consumption of fish, all soybean products, tofu (bean curds), and natto (fermented soybeans) was associated with decreased risk. ORs of the fourth vs. first quartile and 95% confidence intervals (95%CIs) were 0.45 (0.20-1.02) for fish, 0.53 (0.24-1.14) for all soybean products, 0.47 (0.20-1.08) for tofu, and 0.25 (0.05-1.24) for natto. Consumption of fish and natto showed significantly decreasing linear trends for risk (P < 0.05). Consumption of meat was significantly associated with increased risk (the OR of the second vs. first quartile was 2.19, 95%CI 1.00-4.81). Consumption of milk, fruits, all vegetables, green-yellow vegetables, and tomatoes showed no association. Our results provide support to the hypothesis that the traditional Japanese diet, which is rich in soybean products and fish, might be protective against prostate cancer.

Adenocarcinoma↗

PubMed2004

Analysis of the prevalence of bacterial vaginosis and Chlamydia trachomatis infection in 6083 pregnant women at a hospital in Otaru, Japan.

AIM: Our aims were to evaluate the prevalence of bacterial vaginosis (BV), Chlamydia trachomatis (C. trachomatis) infection and Mobiluncus spp. infection among pregnant women in Otaru, Hokkaido, Japan according to the month and year of the first prenatal visit, and to evaluate their risk factors. METHODS: Six thousand and eighty-three pregnant women who were seen consecutively at our hospital between 1993 and 2000, were enrolled in the study. Vaginal and endocervical swabs were subjected to Gram stain and detection of C. trachomatis. Univariate and multivariate methods were used to investigate the association between each infection and potential risk factors including age, gravidity, parity, history of dilatation and curettage (D & C), and history of natural abortion. RESULTS: The annual rate of BV increased from 13.6% in 1993 to 21.4% in 2000. The annual rate of C. trachomatis infection was relatively constant. The prevalence of bacterial vaginosis, C. trachomatis infection and Mobiluncus spp. infection over the 8-year period was 18.2%, 4.2%, and 4.1%, respectively. The prevalence of the three infections was significantly higher among teenagers and among women with a history of D & C. The prevalence of C. trachomatis and Mobiluncus spp. infections was significantly higher among women with no history of delivery. BV was not associated with parity on multivariate analysis. The monthly prevalence of BV was significantly higher in May than in December, and the monthly prevalence of C. trachomatis infection was high in August. CONCLUSION: The differences in the annual and monthly infection patterns between BV and C. trachomatis infection suggest that the etiologies of the two infections differ.

Adolescent↗

PubMed2003

Validation of Urdu Interaction with Disabled Persons scale.

This study developed a valid and reliable Urdu language measure that can be used for assessing attitudes toward persons with physical disability in Pakistan. The Interaction with Disabled Persons scale (IDP), which measures attitudes of discomfort with interaction with disabled people, is a scale with established validity and reliability in English and other languages. An Urdu translation was back-translated to English and then reviewed by a committee to develop cultural validity. Data were collected from 591 Urdu-speaking Pakistani people. Factor analysis extracted four factors that accounted for 55% of the variance and reflected factors found in 12 previous studies. Cronbach's alpha described moderate internal consistency for the IDP.

Adolescent↗

PubMed2003

[Path-analysis model of lifestyle factors and subjective health: the Healthy Japan 21 questionnaire survey in Obihiro].

PURPOSE: The purpose of this study was to determine health problems of citizens of the city of Obihiro with reference to the Healthy Japan 21 plan. METHOD: The subjects were a total of 2,000 men and women (6-74 years old) who were selected at random from the resident ledger of Obihiro. The questionnaire included the 6 fields (nutrient intake/dietary habits, physical activity/exercise, rest/mental health, tobacco, alcohol, dental health) of Healthy Japan 21. The path-analysis model was used by sex, in order to examine the relationship between lifestyle factors (dietary habits, restful sleep, stress, smoking habits, alcohol intake) and subjective health. RESULTS: A total of 979 subjects (49.0%) responded. The items that showed a higher proportion than for all Japan were as follows: the proportions of persons who felt stress, required a drug or alcohol to sleep, drank heavily, and were female smokers. In questions about the harm caused to health by smoking, the following items showed lower awareness than deserved: bronchitis, gastric ulcer, problems with regard to pregnancy, and periodontitis. The following characteristics were found in the path-analysis: 1) If sleep rest is sufficient, subjective health is unaffected by stress in men and women; 2) Smoking affects dietary habits in men and women, especially in the latter; 3) Heavy smoking affects subjective health in men and women independent of whether dietary habits are good; 4) There is a positive relation between drinking and subjective health in women. CONCLUSION: This study showed that stress and smoking are problems for the health of citizens of the city of Obihiro, and suggested that the best measure to counter stress is sufficient sleep, while to counter smoking spread of knowledge about the harm to health caused by smoking is best.

Adolescent↗

PubMed2002

Delphilin: a novel PDZ and formin homology domain-containing protein that synaptically colocalizes and interacts with glutamate receptor delta 2 subunit.

The glutamate receptor delta2 (GluRdelta2) subunit is selectively expressed in cerebellar Purkinje cells and plays an important role in cerebellar long-term depression, motor learning, motor coordination, and synapse development. We identified a novel GluRdelta2-interacting protein, named Delphilin, that contains a single PDZ domain and formin homology (FH) domains FH1 and FH2 plus coiled-coil structure. As far as we know, this is the first reported protein that contains both PDZ and FH domains. Yeast two-hybrid and surface plasmon resonance (SPR) analyses indicated that Delphilin interacts with the GluRdelta2 C terminus via its PDZ domain. This was also supported by coimmunoprecipitation experiments using a heterologous expression system in mammalian cells. Yeast cell and SPR analyses also demonstrated the possibility that the FH1 proline-rich region of Delphilin interacts with profilin, an actin-binding protein, and with the Src homology 3 domain of neuronal Src protein tyrosine kinase. In situ hybridization demonstrated the highest expression of Delphilin mRNA in Purkinje cells. Delphilin polypeptide was highly enriched in the synaptosomal membrane fraction of the cerebellum and coimmunoprecipitated with the GluRdelta2 subunit. The post-embedding immunogold technique demonstrated that Delphilin is selectively localized at the postsynaptic junction site of the parallel fiber-Purkinje cell synapse and colocalized with GluRdelta2. Thus, Delphilin is a postsynaptic scaffolding protein at the parallel fiber-Purkinje cell synapse, where it may serve to link GluRdelta2 with actin cytoskeleton and various signaling molecules.

Animals↗

PubMed2002

Aberrant methylation of multiple genes and clinicopathological features in oral squamous cell carcinoma.

The purpose of this study was to examine the methylation profile of various oral squamous cell carcinomas and to correlate the methylation of particular chromosomal loci with the clinicopathological features of the tumors. A semiquantitative analysis of the methylation status of 12 loci in 96 primary tumors and 13 cell lines was carried out. Methylation frequency was calculated as the percentage of methylated alleles detected by bisulfate-PCR. Of the 12 loci examined, 9 (p16INK4A, p15INK4B, p14ARF, DCC, DAP kinase, MINT1, MINT2, MINT27, and MINT31) exhibited aberrant methylation at various frequencies, whereas 3 (hMLH1, HRK, and CACNA1G) showed no methylation. Dense methylation of the 5' CpG island of DAP kinase and MINT1 was well correlated with loss of gene expression. In addition, methylation of DCC was correlated with bone invasion by gingival tumors (P = 0.036), with aggressive invasiveness of tumors of the tongue (P = 0.046), and with reduced survival (P = 0.050). Methylation of MINT1 and MINT31 also correlated with poor prognoses (P = 0.058 and 0.041), whereas methylation of p14ARF correlated with a good prognosis (P = 0.021). Cox regression analysis showed methylation of MINT31 to be an independent predictor of outcome (hazard ratio, 3.79; 95% confidence interval, 1.58-9.10) and to be associated with the T4 disease group (hazard ratio, 5.71; 95% confidence interval, 1.25-26.07). Analysis of DNA methylation is a useful approach to evaluation of the biological characteristics of oral cancers and may be a useful diagnostic indicator of patient prognosis.

Biomarkers, Tumor↗

PubMed2000

A Review of Cohort Studies on the Association Between History of Diabetes Mellitus and Occurrence of Cancer.

We conducted a review of previous cohort studies on the association between a history of diabetes mellitus (DM) and the occurrence of cancer. We limited the papers to those concerning cohort studies on 9 cancer sites, i.e. the kidney, liver, biliary tract, pancreas, colon or rectum, prostate, breast, endometrium, and ovary, in addition to all cancers. With regard to kidney, liver, biliary tract, pancreatic, colorectal, breast, and endometrial cancers, the risk of cancer development has been consistently reported to be positively associated with DM by two or more cohort studies. In contrast, DM was shown to relate negatively to the risk of prostate cancer by two cohort studies. However, there were no cohort studies which showed an either significantly positive or negative association of DM with ovarian cancer. Elevated levels of insulin or IGFs among DM patients have been proposed as a causal mechanism of increased risk for most of the reviewed cancers. In addition, increased estrogen levels in DM patients have been suggested to explain the casual mechanism of increased risk for kidney, breast and endometrial cancers, and decreased risk for prostate cancer. On the other hand, the possibility of detection bias has been suggested in the association of DM with the risk of most of these cancers. Obesity and heavy consumption of alcohol have been indicated as confounding factors in the relationship of DM to the risk for some of them. Thus, further studies are necessary for firm conclusions regarding the association of DM with cancer risk.

Journal Article↗

PubMedDate not supplied

Magnitude of arsenic toxicity in tube-well drinking water in Bangladesh and its adverse effects on human health including cancer: evidence from a review of the literature.

Only after a decade from 1993, arsenic contamination of groundwater in Bangladesh has been reported as the biggest arsenic catastrophe in the world. It is a burning public health issue in this country. More than 50 percent of the total population is estimated at risk of contamination. Already thousands of people have been affected by the disease arsenicosis. Many more may be on the way to manifest lesions in future. We conducted a review of previous studies and published articles including MEDLINE database on this issue. We found that 59 districts out of 64 have been already affected by arsenic in underground drinking water, where this particular source of drinking water is the main source for 97 percent of the rural people. The water is unfortunately now a great threat for the human being due to high level of arsenic. Continuous arsenic exposure can lead people to develop arsenicosis, which in turn elevates the risk of cancer. Skin lesions are the most common manifestations in arsenicosis patients. Relatively poor rural people and other socio-economically disadvantaged groups are more affected by this exposure. Until now cancer patients have been relatively limited in Bangladesh. One of the reasons may be that several years are needed to show cancer manifestations from the beginning of arsenic exposure. But it is suspected that after some years a large number of patients will appear with cancer in different sites for arsenic exposure in drinking water. Various studies have been conducted in arsenic affected countries - notably in Argentina, Chile, China, Japan, and Taiwan -to find the potential of arsenic exposure to cause development of cancer. Among the arsenic related cancers, liver, lung, skin, bladder and kidney cancers are reported to be prevalent in these countries. Unfortunately no scientific study has been yet conducted in Bangladesh to find the relationship between arsenic exposure and cancers in different sites of the body. So our aim is to conduct an ecological as well as a case-control study in the country in the future.

Adolescent↗

PubMedDate not supplied

Higher consumption of green tea may enhance equol production.

BACKGROUND: Our previous case-control study revealed that Japanese living in Japan and Koreans living in Korea can be divided into equol producers who have an ability to metabolize daidzein to equol and non-producers, and that the incidence of prostate cancer is higher in the latter group. In the present study, we examined relationships between type of food intake and the capacity for equol production in Japanese subjects. METHODS: The subjects were the individuals analyzed for the ability to produce equol in our previous study and newly registered cases. From December 2000 to December 2002, 276 hospitalized patients were interviewed face-to-face and blood samples were collected before breakfast. These included 122 patients with prostate cancer and 154 age-matched controls. RESULTS: The frequency of equol producers (0.5 ng/ml or more) among cases and controls was 29% and 45%, respectively (p = 0.004). The consumption of soybeans and green tea were significantly higher in equol producers than in the non-producers (p<0.05). By contrast, the consumption of selenium and fiber was significantly lower in equol producers (p<0.05). CONCLUSIONS: Our results suggest that higher consumption of soybean and green tea are strongly related to the establishment of a capacity for equol production.

Aged↗

PubMedDate not supplied

Dietary habits and cancer mortality among middle aged and older Japanese living in hokkaido, Japan by cancer site and sex.

Dietary factors are thought to be closely associated with the development of human cancers and hence numerous studies in this area have already been conducted in the United States and other Western countries. Comparatively few prospective studies have been published in Japan, especially for Hokkaido people. The present investigation was therefore performed to assess links between four leading cancers and some of the Japanese common dietary factors through a cohort study (1984-2002) in Hokkaido by analyzing 1,524 men and 1,634 women separately aged 40 and over. Adjusted Cox proportional hazard regression was used to calculate the relative risk (RR) for each dietary factor. For men, two dietary factors, miso soup (RR=0.2, 95% confidence interval (95%CI)=0.1-0.8) and pickled vegetables (RR=0.2, 95%CI=0.1-0.8) were associated with lower risk for stomach and colorectal cancer respectively. For women, three factors, namely salty confectionary (RR=3.5, 95%CI=1.1-10.9), black tea (RR=3.8, 95%CI=1.1-13.6), and carbonated drink/juice (RR=3.9, 95% CI=1.4-11.1) appeared related to an elevated risk of stomach cancer. However, further analysis simultaneously with all other adjusted factors indicated only carbonated drink/juice (RR=3.1, 95%CI=1.1-8.9) to present a significant risk factor for stomach cancer. One factor, namely wild edible plants (RR=3.3, 95%CI=1.1-9.8), increased the risk for colorectal cancer in women. None of the dietary components were significantly associated with lung or pancreatic cancers. This study also indicated a wide variation in the impact of dietary factors by sex and cancer site, in line with earlier work, pointing to a necessity for careful interpretation. Further epidemiological investigations by sex with more study subjects and confounding factors will be useful for determining the contribution of individual dietary factors to development of human cancers in Hokkaido, Japan.

Adult↗

PubMedDate not supplied

A case-control study of multiple myeloma in Japan: association with occupational factors.

Recently the incidence rate of multiple myeloma (MM) has increased in Japan. Epidemiologic efforts have suggested that certain occupational and chemical exposures are likely to increase the risk for MM. We therefore performed a case-control study of MM, examining occupational factors. Data for 57 cases and 57 controls were obtained from Sapporo Medical University Hospital and its affiliated hospitals in Hokkaido. Controls were matched to each case by gender, age (+/- 5 years) and hospital. Detailed information regarding several factors possibly related to MM was obtained by interviews in hospitals. Odds ratios (ORs) and 95% confidence intervals (95%CIs) were calculated with adjustment for cigarette smoking as confounding factor. The occupational category of agriculture and fishery showed a significant association with increased risk (OR = 5.89, 95% CI = 1.24-28.04). Occupational exposure to chemical products including organic solvents or petroleum showed a significant association with increased risk (OR = 8.05, 95% CI = 1.01-64.45). Medical histories of operation for appendicitis and blood transfusion were associated with decreased risk, but not significantly. Our results suggested that occupational exposure to chemicals might play a role in the risk of MM.

Adult↗