Metagenomic Analysis of Biliary Microbial Flora in Patients with Gallbladder Cancer or Gallstones-Associated Chronic Cholecystitis.

Biliary dysbiosis is associated with gallbladder cancer (GBC). We aimed to look for biliary bacteria specifically detected in GBC patients. We used 16S rRNA-based metagenomic analysis to elucidate biliary microbiota in 30 GBC and 30 gallstones-associated chronic cholecystitis patients. Relative abundance of five genera, Streptococcus, Enterococcus, Halomonas, Escherichia and Caulobacter was significantly associated with GBC. Of 15-species, 7 were detected significantly higher in GBC, Streptococcus anginosus, Streptococcus constellatus, Streptococcus intermedius, Actinomyces bowdenii, Actinomyces israelii, Actinomyces gerencseriae, and Escherichia fergusonii were biosafety level-2 infectious bacteria; other 8 species were biosafety level-1 bacteria. These bacterial species may be involved in pathogenesis of GBC.

Risk factors for gallbladder cancer development in northern India: A gallstones-matched, case-control study.

Background & objectives: A high incidence of gallbladder cancer (GBC) is observed in northern India. This study was aimed to identify the factors involved in developing GBC in this region. Methods: A gallstones-matched, case-control study was conducted in northern India. Ninety nine patients with GBC and gallstones (33 men and 66 women, mean age of 51.4 yr) comprised the case group, while 99 patients with cholelithiasis (40 men and 59 women, mean age of 45.7 yr) comprised the control group. All participants were interviewed to complete 183 questionnaire items that included 105 food items. Potential risk factors were identified using a multivariate analysis adjusted for age and sex. Significant risk factors were identified using a stepwise logistic-regression analysis. Results: Age (≥50 yr), education (illiterate), socioeconomic status (≤below poverty line), bowel habits (≤once a day), hypertension history, hypotensive drug use, non-vegetarian diet, use of firewood for cooking, tap water drinking, hand pump water drinking and high consumption of coffee and sweets were identified as the potential risk factors. In women, factors included menarche (<13 yr), number of pregnancies (≥3 pregnancies) and parity (≥3 babies). Of these factors, age, education, bowel habits, tap water drinking and multiple pregnancy and/or multiparity were identified as significant risk factors, whereas a high consumption of coffee and sweets or hypotensive drug use and/or hypertension history were protective factors. Interpretation & conclusions: Poor bowel habits and drinking unsafe water appear to be the main risk factors for developing GBC. These are, however, modifiable factors which are capable of decreasing the risk of GBC in the north Indian population.

Roles of Salmonella typhi and Salmonella paratyphi in Gallbladder Cancer Development.

BACKGROUND: Typhoid (Salmonella typhi and paratyphi) carriers and gall bladder cancer (GBC) are endemic in northern India. Results of previous studies about association of typhoid carriers with GBC are inconsistent. We studied antibodies against Salmonella typhi and paratyphi in serum samples of patients with GBC. METHODS: We performed modified Widal test for antibodies against Salmonella typhi (Vi and O) and Salmonella paratyphi (AO and BO) antigens in patients with GBC (n=100), xanthogranulomatous cholecystitis (XGC, n=24), chronic cholecystitis (CC, n=200) and healthy controls (HC, n=200). RESULTS: Serum antibodies against Salmonella were more frequently positive in GBC (22%) and XGC (29%), particularly in males in age ≥50 years (GBC: 47% and XGC: 50%) vs. HC (0) (p <0.01). Vi antibody was more common in GBC (13%, OR:9.8) and XGC (8%, OR:5.9) than HC (2%). O antibody was more common in GBC (8%, OR: 8.6) and XGC (8%, OR: 9.0) than HC (1%). O antibody was also more common in males with GBC (12%) than CC (1%) and HC (1%) (P=0.02 and p <0.001, respectively). AO (6%) and BO (4%) antibodies were detected in GBC, particularly in males, than HC (0), (p <0.01). Salmonella antibodies were more frequent in GBC with GS than those without GS (50% vs. 20%, OR=3.94, P=0.01). CONCLUSIONS: Salmonella carrier state was more common in GBC and XGC, particularly in elderly males than HC. The Vi antibody was more common in GBC and XGC than HC. Salmonella infection was more common in GBC with GS than those without GS.

Evidence that genetic variants of metabolic detoxication and cell cycle control are not related to gallbladder cancer risk in Chilean women.

BACKGROUND AND AIMS: High consumption of red chili pepper has been shown to be a risk factor for gallbladder cancer (GBC) in Chilean women. However, genetic factors in addition to this and other environmental factors may also be associated with an increased risk of GBC. We aimed to examine the associations of cytochrome P450 1A1 (CYP1A1), glutathione S-transferase class mu (GSTM1), and tumor protein p53 (TP53) polymorphisms with the risk of GBC in Chilean women. METHODS: A hospital-based case-control study of 57 patients with GBC, 119 patients with gallstones, and 70 controls was conducted. The statuses of the polymorphisms CYP1A1 rs4646903, CYP1A1 rs1048943, and TP53 rs1042522 were assayed using Custom Taqman SNP Genotyping Assays and TaqMan SNP Genotyping Assay. GSTM1 deletion polymorphism was detected by allele-specific PCR analysis. RESULTS: No significant differences in the genotypic or allelic frequencies in the CYP1A1, GSTM1, and TP53 polymorphisms were found between the three groups. CONCLUSION: These genetic variants were not related to an increased risk of GBC in Chilean women. Other polymorphisms, such as red-chili-pepper-related polymorphisms, may contribute to the development of GBC in Chilean women.

Long-term suicide mortality rates decrease in men and increase in women after the Niigata-Chuetsu earthquake in Japan.

A devastating earthquake causes psychological distress, and may increase suicide mortality thereafter, yet previous studies have made inconsistent conclusions regarding this issue. The purpose of the present study was to determine whether the 2004 Niigata-Chuetsu earthquake in Japan affected long-term mortality from suicide. We conducted a comparative study of suicide mortality rates during the 5-year period preceding and the 3-year period following the earthquake in the disaster area and a control area in Niigata Prefecture, by analyzing death certificate data from October 1, 1999, to September 30, 2007. In men, baseline suicide mortality rates (5 years preceding the earthquake) were 48.4 per 100,000 person-years in the disaster area and 46.1 in the control area, and suicide mortality rates during the 3-year period following the earthquake were 46.0 and 45.1, respectively. In women, baseline suicide mortality rates were 22.3 in the disaster area and 18.7 in the control area, and post-earthquake suicide mortality rates were 20.2 and 15.3, respectively. In consequence, the decrease in suicide mortality rate during the 3 years post-earthquake was significantly higher in the disaster area (2.5) than in the control area (1.0) (p = 0.0013) in men, whereas the decrease in suicide mortality rate was 2.1 in the disaster area and 3.0 in the control area (p = 0.1246) in women. We have concluded that the long-term mortality from suicide after the earthquake decreases in men and increases in women, suggesting that post-earthquake suicide mortality is sex-dependent. Post-earthquake suicide prevention strategies should more aggressively target women.

Bone fracture in physically disabled children attending schools for handicapped children in Japan.

OBJECTIVE: Very few epidemiologic studies on bone fracture have been conducted in schools for handicapped children (Yogo schools). The aim of this study was to clarify the frequency and risk factors of bone fracture in physically disabled children in Japan. METHODS: We used a cross-sectional design to examine 525 physically disabled children in 38 Yogo schools in the Hokuriku-Koshinetsu District of Japan. The questionnaire surveyed information on participant sex, age, level of physical disability, and bone fracture history. Information on fractures was obtained, including number of fractures over participant lifetime, age when fractures occurred, location, and cause. One-year-period prevalence and lifetime prevalence were defined as the proportion of subjects with incident fractures in the previous year and with a history of fracture, respectively. RESULTS: Participant ages ranged from 6 to 15 years, and 66.3% had cerebral palsy (CP). The 1-year-period prevalence was 3.6% and lifetime fracture prevalence was 9.7%. The 1-year-period prevalence in the age groups of 6-9, 10-12, and 13-15 years was 2/184 (1.1%), 5/171 (2.9%), and 12/164 (7.3%), respectively (P for trend = 0.0031). There were no differences in period prevalence between sexes, and this was not associated with presence of CP. Multiple logistic regression analysis showed that age and presence of one joint contracture in the lower limbs or hip were independently associated with occurrence of bone fracture over participant lifetime. CONCLUSIONS: Physically disabled children are at high risk of bone fracture, and further risk factors should be determined.

Low calcium intake is associated with increased bone resorption in postmenopausal Japanese women: Yokogoshi Study.

OBJECTIVE: Low Ca intake is common among Japanese women, but its effect on bone metabolism has not been fully elucidated. The aim of the present study was to determine the relationship between Ca intake and serum markers of bone turnover in postmenopausal Japanese women. DESIGN: A cross-sectional study. SETTING: A community setting. SUBJECTS: Subjects were 595 home-dwelling postmenopausal Japanese women. Ca intake was assessed by a validated FFQ. Serum type I collagen cross-linked N-telopeptides (NTX) and osteocalcin were measured as markers of bone turnover. The relationships between demographic characteristics, lifestyles, serum Ca, vitamin D and intact serum parathyroid hormone and bone turnover were also assessed. RESULTS: The average age of the subjects was 64.5 (sd 5.8) years and the mean Ca intake was 527 (sd 160) mg/d. Ca intake was significantly associated with serum NTX (P = 0.0104), but not with serum osteocalcin. Mean serum NTX concentration in the lowest quartile of Ca intake (<417 mg/d) was significantly higher than in the fourth, referent quartile. Among these Japanese postmenopausal women, very low Ca intake (less than approximately 400 mg/d) was associated with increased bone resorption but not bone formation. CONCLUSIONS: Increased bone resorption may be one mechanism by which this Ca-depleted population normalizes bone metabolism and prevents osteoporosis.

Unhealthy maternal lifestyle leads to rapid infant weight gain: prevention of future chronic diseases.

Infants' rapid (catch-up) weight gain is associated with later obesity and chronic adult diseases. The aim of this study was to determine maternal and environmental factors related to rapid weight gain at one month and 18 months after full-term birth in Japan. Subjects were 1,524 infants and their mothers who visited the 18-month check-up in Niigata City between October 1, 2007 and September 30, 2008. An anonymous questionnaire elicited information on the infant's weight (at birth, 1 month, and 18 months), sex, feeding method, presence of food allergy, gestational age, and caregiver. Mother's information was height, pre-pregnancy weight, pregnancy weight gain, age at delivery, pregnancy toxicosis, number of daily meals during pregnancy, smoking and drinking habits. Some questionnaire items were obtained from a maternal and child health handbook. Independence of predictors for rapid weight gain (vs. slow or average weight gain), i.e. a score gain of 0.67 SD, during the first month and first 18 months was tested by multiple logistic regression analysis. In the first month, having a meal once or twice daily during pregnancy (P = 0.0016) and daily smoking in pre-pregnancy (P = 0.0175) were associated with rapid weight gain. In the first 18 months, use of daycare (P = 0.0083) and daily drinking in pre-pregnancy (P = 0.0130) were associated with rapid weight gain. We conclude that mother's pre-pregnancy smoking and drinking, dieting during pregnancy, and infant daycare attendance lead to rapid infant weight gain. Controlling these factors may prevent future chronic adult lifestyle-related diseases.

Carcinogen Metabolism Pathway and Tumor Suppressor Gene Polymorphisms and Gallbladder Cancer Risk in North Indians: A Hospital-Based Case-Control Study.

BACKGROUND: Carcinogen metabolism pathway and tumor suppressor gene polymorphisms have been reported to be associated with increased gallbladder cancer risk. However, the association of genetic variants and gallbladder cancer risk in Indians are not well studied. We examined whether genetic polymorphisms of metabolic enzymes cytochrome P450 1A1 and glutathione S-transferase and tumor suppressor gene p53 (TP53) are associated with an increased risk of gallbladder cancer in North Indians. METHODS: This hospital-based case-control study was conducted in 96 gallbladder cancer patients with gallstones (cases) and 93 cholelithiasis patients (controls) at the Sanjay Gandhi Postgraduate Institute of Medical Sciences in Lucknow, India from July 2014 through May 2017. Genomic DNA was extracted from white blood cells of each patient using a simple salting-out procedure. The genotypic frequencies of CYP1A1 rs4646903, CYP1A1 rs1048943, and TP53 rs1042522 polymorphisms were investigated using TaqMan SNP Genotyping Assay and GSTM1 and GSTT1 polymorphisms were analyzed using the multiplex PCR assay. RESULTS: The frequency of CC genotype of TP53 rs1042522 polymorphism was 27.1% (26/96) in cases and 12.9% (12/93) in controls. The CC genotype was associated with an increased risk of gallbladder cancer in North Indians (age- and sex-adjusted odds ratio, 2.81; 95% confidence interval, 1.19-6.61; P = 0.02). No significant differences in genotypic and allelic frequencies of the metabolic pathway gene polymorphisms were found between cases and controls. CONCLUSIONS: Our data provide preliminary evidence that the CC genotype of the TP53 rs1042522 polymorphism may be associated with an increased risk of gallbladder cancer in North Indians.

Tumor Protein p53 and K-ras Gene Mutations in Peruvian Patients with Gallbladder Cancer

Background: Recent studies have shown that genetic alterations are associated with the effect of patient geographic location on gallbladder cancer development. Peru has a high incidence of gallbladder cancer, but causative factors have not yet been identified. We examined the frequency of mutations in TP53 and K-ras genes in Peruvian patients with gallbladder cancer, and compared this with data from Bolivia, Hungary, Chile, and Japan, which have a high gallbladder cancer incidence. Methods: DNA was extracted from formalin-fixed paraffin-embedded gallbladder tissue sections of 30 gallbladder cancer patients (9 men and 21 women) obtained using microdissection. Mutations in exons 5 to 8 of TP53 and codons 12, 13, and 61 of K-ras were examined using direct sequencing. Results: TP53 mutations were observed in 10 (33.3%) of patients, but K-ras mutations were absent. Nine (90%) TP53 mutations were point mutations (7 missense and 2 silent mutations), and the most frequent substitution was a G:C to A:T transition. G:C to A:T transitions at the CpG site or G:C to T:A transversions were found in one patient each. No significant differences were found in the frequency of TP53 and K-ras mutations among patients in the 5 countries. Conclusions: Our findings suggest that endogenous mechanisms and exogenous carcinogens may affect the carcinogenic process in Peruvian gallbladder cancer patients, similar to that in Bolivian patients. Further studies with a larger sample size are needed to clarify these findings.

Vitamin D status, bone mass, and bone metabolism in home-dwelling postmenopausal Japanese women: Yokogoshi Study.

Little has been understood about vitamin D status in relation to bone health in Asian women. The purpose of this study was to identify how the serum 25-hydroxyvitamin D (25[OH]D) concentration is associated with bone mass and bone metabolism. This cross-sectional, community-based epidemiologic study was conducted among 600 ambulatory postmenopausal women. The serum 25(OH)D concentration was measured with radioimmunoassay. Other blood biochemical measurements were intact parathyroid hormone and markers of bone turnover, including osteocalcin and type I collagen cross-linked N-telopeptides. Bone mineral density (BMD) of the lumbar spine and right femoral neck were measured with the dual-energy X-ray absorptiometry method using a QDR4500a. The mean serum 25(OH)D concentration was 55.6 nmol/L (SD 14.6). Serum 25(OH)D concentration was linearly associated with BMD of the femoral neck (R(2)=0.020, P=0.003), but not with BMD of the lumbar spine. Odds ratios (ORs) for low BMD (defined as t score < or =-2.5 SD) were calculated for strata defined by 25(OH)D concentration. The prevalence of low BMD of the lumbar spine was significantly higher in the 40- to 50-nmol/L 25(OH)D group (adjusted OR=3.0, 95% CI: 1.3-7.0) compared to the reference group (> or =70 nmol/L). Prevalence of low BMD for the femoral neck was significantly higher in the 30- to 40-nmol/L (adjusted OR=3.6, 95% CI: 1.1-12.1) and the 40- to 50-nmol/L (adjusted OR=7.6, 95% CI: 2.5-23.2) groups compared to the reference group (> or =70 nmol/L). The mean serum concentration of intact PTH was significantly higher in subjects with serum 25(OH)D <50 nmol/L compared to those with serum 25(OH)D > or =50 nmol/L. The present study suggests that higher serum 25(OH)D concentrations are associated with increased BMD of the femoral neck, and that a serum 25(OH)D concentration of at least 70 nmol/L is needed to obtain high BMD of the femoral neck, and that of at least 50 nmol/L is needed to achieve normal PTH levels and prevent low BMD in home-dwelling postmenopausal Japanese women.

Plasma Helicobacter pylori Antibody Titers and Helicobacter pylori Infection Positivity Rates in Patients with Gallbladder Cancer or Cholelithiasis: a Hospital-Based Case-Control Study

Objective: Gallbladder cancer is the commonest gastrointestinal cancer in northern Indian women. Some studies have examined the association between Helicobacter pylori infection and gallbladder cancer risk, but findings have been inconsistent. We aimed to examine the association between H. pylori infection and gallbladder cancer in Indian people. Materials and Methods: We conducted a hospital-based case-control study including 100 gallbladder cancer patients with gallstones who were 32 to 79 years old (cases; 72 women and 28 men), and 100 cholelithiasis patients aged 14 to 75 years (controls; 65 women and 35 men). All patients had a diagnosis of gallbladder cancer or cholelithiasis at the Sanjay Gandhi Post Graduate Institute of Medical Sciences in Lucknow having a high gallbladder cancer incidence in northern India, from May 2014 through July 2017. Plasma samples were collected from all patients before surgical treatment. Plasma H. pylori antibody titer was measured by the latex agglutination method and an autoanalyzer. H. pylori infection was defined as antibody titer ≥10 U/mL. Plasma antibody titers and H. pylori infection positivity rates were compared between cases and controls. Results: Mean plasma antibody titers (standard deviation, range) were 11.1 U/mL (11.6, 0­78) in cases and 13.6 U/mL (23.0, 1­164) in controls. H. pylori infection positivity rates were 41% and 42% in cases and controls, respectively. No significant differences in antibody titers or H. pylori infection positivity rates were found between cases and controls. Conclusions: We found no evidence of H. pylori infection as an important risk factor for gallbladder cancer in Indian people.

Metagenomics of Microbial Communities in Gallbladder Bile from Patients with Gallbladder Cancer or Cholelithiasis

Salmonella typhi and Helicobacter infections have been shown to increase risk of gallbladder cancer (GBC), but findings have been inconsistent. Other bacterial infections may also be associated with GBC. However, information on microbial pathogens in gallbladder bile of GBC patients is scarce. We aimed to investigate the microbial communities in gallbladder bile of patients with GBC and cholelithiasis (CL). Seven GBC patients and 30 CL patients were enrolled in this study. Genomic DNA was extracted from bile and the V3-V4 region of 16S rRNA was amplified. The sequencing results were compared with the 16S database, and the bacteria were identified by homology searches and phylogenetic analysis. DNA was detected in the bile of three GBC (42.9%; Bolivia, 1; Chile, 2) and four CL patients (13.3%; Bolivia, 1; Chile, 3). Of the 37 patients, 30 (81.1%) were negative and unable to analyze. Salmonella typhi and Helicobacter sp. were not detected in bile from any GBC patients. As the predominant species, Fusobacterium nucleatum, Escherichia coli, and Enetrobacter sp. were detected in bile from GBC patients. Those in bile from CL patients were Escherichia coli, Salmonella sp., and Enerococcus gallinarum. Escherichia coli was detected in bile samples from both GBC and CL patients. Whether the bacteria detected in bile from GBC patients would associated with the development of GBC warrant further investigation.

Polymorphisms of cytochrome P450 1A1, glutathione S-transferase class mu, and tumour protein p53 genes and the risk of developing gallbladder cancer in Japanese.

OBJECTIVES: To examine the relationship between genetic polymorphisms of cytochrome P450 1A1 (CYP1A1), glutathione S-transferase class mu (GSTM1), and tumour protein p53 (TP53) genes, and gallbladder cancer (GBC) risk, a case-control study was conducted. DESIGN AND METHODS: Genotypes of CYP1A1 T3801C, CYP1A1 Ile462Val, GSTM1, and TP53 Arg72Pro were determined in 54 cases of GBC and 178 controls. RESULTS: The age-adjusted odds ratios (ORs) for the Ile/Val genotype of CYP1A1 Ile462Val polymorphism in women and the Arg/Pro genotype of TP53 Arg72Pro polymorphism in men were observed to be 2.70 (95% CI: 1.14-6.40) and 4.32 (95% CI: 1.08-17.2), respectively. No significant differences in the genotypic frequencies of CYP1A1 T3801C and GSTM1 polymorphisms were observed between controls and cases in both men and women. CONCLUSION: These results suggest that the Val allele of CYP1A1 Ile462Val polymorphism and the Pro allele of TP53 Arg72Pro polymorphism contribute to an increased risk of GBC among Japanese women and men, respectively.

Magnesium intake and bone mineral density in young adult women.

The purpose of this study was to determine a possible association between magnesium intake and bone mass in young adult women. Subjects consisted of 106 female university students aged 19-25 years. Calcium and magnesium intakes were evaluated using the duplicate sampling method on three weekdays. Spinal and femoral bone mineral density (BMD) was measured by dual energy X-ray absorptiometry. Mean magnesium intake was 139 mg/day (median 127, SD 54). The correlation between magnesium intake and BMD was of borderline significance (r = 0.175, p = 0.073) for the femoral neck, and was insignificant (r = 0.084, p = 0.391) for the lumbar spine. However, the partial correlation between magnesium intake and BMD of the femoral neck (r = -0.027, p = 0.788), adjusted for calcium intake, was not significant. In conclusion, we did not find an association between magnesium intake and bone mass in young women, and calcium intake needs to be included as an important, potential confounding factor when exploring such an association.

[Fracture-related medical cost of aged people in Niigata Prefecture, Japan: analysis of data from health insurance claims].

OBJECTIVES: The purpose of this study is to determine the fracture-related medical cost of aged people to reduce such cost. METHODS: Using health insurance claims, we obtained data on the number of aged people (> or =60 years of age) with fractures among members of the National Health Insurance Organization in Niigata Prefecture and their fracture-related medical cost, every May from 2003 to 2005. We analyzed these data and stratified them by sex, age (5-year age range), and hospitalization history. RESULTS: The average number of fractures per 100,000 people and the fracture-related medical cost per capita for women were 1,316+/-11 and 1,344+/-66 yen, respectively. These values were found to be more than twofold, those for men (604+/-11 and 556+/-33 yen, respectively). The number of fractures per 100,000 people and the fracture-related medical cost per capita increased with age. The fracture-related medical cost per hospitalization admission, however, did not increase with age. The amount of two-year increase in the fracture-related medical cost of hospitalization per capita was the largest in the > or =85 age group, and increased with the number of fractures. The fracture-related medical cost of people > or =60 years of age in Niigata prefecture was estimated to increase with age for women, but not for men. CONCLUSIONS: It is suggested that lowering the prevalence of fractures among very old women would lead to a decrease in the total fracture-related medical costs. Additional studies are needed to confirm the findings using nation wide data.

Free fatty acid concentrations in gallbladder bile collected from Chilean patients with gallstones.

OBJECTIVES: To evaluate the association between gallstones and biliary free fatty acids (FFAs) as the first attempt to clarify whether biliary FFAs relate to developing gallbladder cancer (GBC) in Chile, which has the highest mortality rate in the world. DESIGN AND METHODS: Gallbladder bile from 21 male and 129 female patients with gallstones from Santiago was collected, and their FFAs were measured. The results were compared with those observed in a similar previous study performed in Niigata and Kochi Prefectures which showed the highest and lowest mortality rates, respectively, for GBC in Japan. RESULTS: Palmitoleic and linolenic acids compositions in Santiago patients were significantly lower than those in Niigata and Kochi patients, though these compositions in Niigata patients were significantly lower than those in Kochi patients. The levels of these FFAs compositions decreased in the order of Kochi, Niigata, and Santiago patients. CONCLUSIONS: Decreased biliary FFAs compositions may relate to developing gallstones and subsequently GBC.

Antibacterial effects of chitosan solution against Legionella pneumophila, Escherichia coli, and Staphylococcus aureus.

Chitosan has been shown to have antibacterial activities on the growth of a wide variety of bacteria. Chitosan solution has been sold commercially for use as an antibacterial agent. Chitosan solution contains not only chitosan but also organic acids as solvents and desalted Japan Sea Proper Water (dJSPW). We aimed to clarify whether chitosan solution has antibacterial activity against bacteria invading bath water, and then to explore the causative factor among these ingredients. The antibacterial activity of full-strength chitosan solution and of 10(2)- and 10(4)-fold chitosan solution diluted with purified water was studied against Legionella pneumophila serogroups 1 (L. pneumophila SG1) and 6 (L. pneumophila SG6), Escherichia coli (E. coli), and Staphylococcus aureus (S. aureus) for 7 days at 37 degrees C. To clarify the causative factor in the antibacterial activity against E. coli, the antibacterial activities of the full-strength and diluted chitosan solutions for 24 h were examined. L. pneumophila SG1 and SG6, and E. coli could not survive in the chitosan solution or in the 10(2)-fold dilute solution for over a day at 37 degrees C. The cells of S. aureus were found to have decreased more than 2.46 log cfu/ml after 1 day of incubation, not only in the chitosan solutions, but also in phosphate buffer solution as a control. No inhibitory effect of dJSPW on the growth of the bacteria was observed. The antibacterial activity of the chitosan solution was lower compared with those of the organic acids solutions, and it increased with decreasing pH value. We observed the antibacterial activity of chitosan solution against L. pneumophila SG1 and SG6, and E. coli, suggesting it may be due to the decreased pH value derived from organic acids rather than from chitosan itself or dJSPW.

CYP1A1, GSTM1, GSTT1 and TP53 Polymorphisms and Risk of Gallbladder Cancer in Bolivians.

The Plurinational State of Bolivia (Bolivia) has a high incidence rate of gallbladder cancer (GBC). However, the genetic and environmental risk factors for GBC development are not well understood. We aimed to assess whether or not cytochrome P450 (CYP1A1), glutathione S-transferase mu 1 (GSTM1), theta 1 (GSTT1) and tumor suppressor protein p53 (TP53) genetic polymorphisms modulate GBC susceptibility in Bolivians. This case-control study covered 32 patients with GBC and 86 healthy subjects. GBC was diagnosed on the basis of histological analysis of tissues at the Instituto de Gastroenterologia Boliviano-Japones (IGBJ); the healthy subjects were members of the staff at the IGBJ. Distributions of the CYP1A1 rs1048943 and TP53 rs1042522 polymorphisms were assayed using PCR-restriction fragment length polymorphism assay. GSTM1 and GSTT1 deletion polymorphisms were detected by a multiplex PCR assay. The frequency of the GSTM1 null genotype was significantly higher in GBC patients than in the healthy subjects (odds ratio [OR], 2.35; 95% confidence interval [CI], 1.03-5.37; age-adjusted OR, 3.53; 95% CI, 1.29-9.66; age- and sex-adjusted OR, 3.40; 95% CI, 1.24-9.34). No significant differences were observed in the frequencies of CYP1A1, GSTT1, or TP53 polymorphisms between the two groups. The GSTM1 null genotype was associated with increased GBC risk in Bolivians. Additional studies with larger control and case populations are warranted to confirm the association between the GSTM1 deletion polymorphism and GBC risk suggested in the present study.