Corrigendum: Antimicrobial susceptibility profiles and tentative epidemiological cutoff values of Legionella pneumophila from environmental water and soil sources in China.

[This corrects the article DOI: 10.3389/fmicb.2022.924709.].

Antimicrobial susceptibility profiles and tentative epidemiological cutoff values of Legionella pneumophila from environmental water and soil sources in China.

Legionnaires' disease (LD), caused by Legionella, including the most prevalent Legionella pneumophila, has been treated primarily with antibiotics. Environmental water and soil are the reservoirs for L. pneumophila. Studying antimicrobial susceptibility using a large number of isolates from various environmental sources and regions could provide an unbiased result. In the present study, antimicrobial susceptibility of 1464 environmental L. pneumophila isolates that were derived from various environmental water and soil sources of 12 cities in China to rifampin (RIF), erythromycin (ERY), clarithromycin (CLA), azithromycin (AZI), ciprofloxacin (CIP), moxifloxacin (MOX), levofloxacin (LEV), and doxycycline (DOX) was investigated, and minimum inhibitory concentration (MIC) data were obtained. We show that regarding macrolides, ERY was least active (MIC90 = 0.5 mg/L), while CLA was most active (MIC90 = 0.063 mg/L). A total of three fluoroquinolones have similar MICs on L. pneumophila. Among these antimicrobials, RIF was the most active agent, while DOX was the most inactive one. We observed different susceptibility profiles between serogroup 1 (sg1) and sg2-15 or between water and soil isolates from different regions. The ECOFFs were ERY and AZI (0.5 mg/L), RIF (0.002 mg/L), CIP, CLA and MOX (0.125 mg/L), LEV (0.063 mg/), and DOX (32 mg/L). Overall, two fluoroquinolone-resistant environmental isolates (0.14%) were first documented based on the wild-type MIC distribution. Not all azithromycin-resistant isolates (44/46, 95.65%) harbored the lpeAB efflux pump. The MICs of the ERY and CLA on the lpeAB + isolates were not elevated. These results suggested that the lpeAB efflux pump might be only responsible for AZI resistance, and undiscovered AZI-specific resistant mechanisms exist in L. pneumophila. Based on the big MIC data obtained in the present study, the same defense strategies, particularly against both CLA and RIF, may exist in L. pneumophila. The results determined in our study will guide further research on antimicrobial resistance mechanisms of L. pneumophila and could be used as a reference for setting clinical breakpoints and discovering antimicrobial-resistant isolates in the clinic, contributing to the antibiotic choice in the treatment of LD.

Effect of radio frequency, ultrasound, microwave-assisted papain, and alcalase hydrolysis on the structure, antioxidant activity, and peptidomic profile of Rosa roxburghii Tratt. seed protein.

Traditional enzymatic hydrolysis methods have defects such as low efficiency and poor bioactivity in the production of active peptides. In this study, radio frequency (RF) technology was innovatively used to assist the hydrolysis of Rosa roxburghii Tratt. seed protein (RTSP) by papain and alcalase. RF-assisted hydrolysis was compared with ultrasound-(US) and microwave (MW)-assisted techniques in terms of the degree of hydrolysis, structure, antioxidant properties, and changes in the peptidome of the hydrolysates to clarify the mechanism of functional change of physically-assisted hydrolysate. All three methods improved hydrolysis efficiency. The degree of hydrolysis (DH) of papain group increased from 6.38% to 7.97%, 9.97% and 8.37% after US-, MW- and RF-assisted hydrolysis, respectively, while the DH of alcalase-treated group increased from 21.13% to 25.66%, 26.03%, and 23.01%, respectively. The in vitro antioxidant capacity and intracellular antioxidant capacity of RTSP and its hydrolysates were measured and evaluated by fuzzy statistical evaluation, and MW-assisted alcalase hydrolysis had the highest in vitro and intracellular antioxidant activity scores of 0.713 and 0.820, respectively. Fourier transform infrared and amino acid composition analysis explained the enhanced antioxidant properties of the hydrolysates. Further peptide profiling showed the physical assistance led to an increase in the species and contents of small molecule antioxidant peptides compared to enzyme treatment alone. Pearson's linear correlation analysis showed that AY, LY, IY, PHW, SVL, LHL, YYV, VYY, and NHAV were significantly correlated with the antioxidant properties of hydrolysates. Our data suggested that physical assistance such as US, MW, and RF were effective to improve the efficiency of enzymatic hydrolysis and produce novel antioxidant peptides. PRACTICAL APPLICATION: In this study, it was found that electromagnetic wave-assisted enzymatic hydrolysis could improve the efficiency of hydrolysis and enhance the antioxidant activity of hydrolysates compared to unassisted means. Compared with MW treatment, RF has the comparable hydrolysis effect, but has the advantages of high penetration ability, good uniformity, and low energy consumption and has greater potential for the production of bioactive peptides.

Quark Cheese Processed by Dense-Phase Carbon Dioxide: Shelf-Life Evaluation and Physiochemical, Rheological, Microstructural and Volatile Properties Assessment.

Dense-phase carbon dioxide (DPCD), a novel non-thermal processing technology, has attracted extensive attention due to its excellent performance in food sterilization and enzyme inactivation without quality deterioration. In this work, we aimed to extend the shelf life of quark cheese with DPCD and explore the effect of DPCD treatment as well as storage time on the quality of quark cheese. The sterilization parameters were optimized by means of orthogonal experiments, and the physiochemical, rheological, microstructural and volatile properties of cheese were investigated. The optimal DPCD treatment (20 MPa, 45 min, 55 °C) successfully extended the shelf life of quark cheese due to its inhibition effect on yeast and was able to slow down the proteolysis and alterations in pH and color of cheese. Cheese processed using DPCD after 14-day storage even displayed similar rheological properties to the control at day 0, from which bound water significantly migrated during storage. Moreover, DPCD contributed to the retention of the volatile profile of cheese during storage. This study demonstrated that DPCD is a promising pasteurization technology for quark cheese to improve its quality stability during storage.

Presence of Viable, Clinically Relevant Legionella Bacteria in Environmental Water and Soil Sources of China.

The distribution of pathogenic Legionella in the environmental soil and water of China has not been documented yet. In this study, Legionella was detected in 129 of 575 water (22.43%) and 41 of 442 soil samples (9.28%) by culture. Twelve Legionella species were identified, of which 11 were disease-associated. Of the Legionella-positive samples, 109 of 129 (84.50%) water and 29 of 41 (70.73%) soil were positive for L. pneumophila, which accounted for about 75% of Legionella isolates in both water and soil, suggesting L. pneumophila was the most frequent species. Soil showed a higher diversity of Legionella spp. as compared with water (0.6279 versus 0.4493). In contrast, serogroup (sg) 1 was more prevalent among L. pneumophila isolates from water than from soil (26.66% versus 12.21%). Moreover, many disease-associated sequence types (STs) of L. pneumophila were found in China. Intragenic recombination was acting on L. pneumophila from both water and soil. Phylogeny, population structure, and molecular evolution analyses revealed a probable existence of L. pneumophila isolates with a special genetic background that is more adaptable to soil or water sources and a small proportion of genetic difference between water and soil isolates. The detection of viable, clinically relevant Legionella demonstrates soil as another source for harboring and dissemination of pathogenic Legionella bacteria in China. Future research should assess the implication in public health with the presence of Legionella in the soil and illustrate the genetic and pathogenicity difference of Legionella between water and soil, particularly the most prevalent L. pneumophila. IMPORTANCE Pathogenic Legionella spp. is the causative agent of Legionnaires' disease (LD), and L. pneumophila is the most common one. Most studies have focused on L. pneumophila from water and clinical samples. However, the soil is another important reservoir for this bacterium, and the distribution of Legionella spp. in water and soil sources has not been compared and documented in China yet. Discovering the distribution of Legionella spp. and L. pneumophila in the two environments may help a deep understanding of the pathogenesis and molecular evolution of the bacterium. Our research systematically uncovered the distributions of Legionella spp. in different regions and sources (e.g., water and soil) of China. Moreover, phylogeny, population structure, and molecular evolution study revealed the possible existence of L. pneumophila with a special genetic background that is more adaptable to soil or water sources, and genetic difference may exist.

Casein-hempseed protein complex via cross-link catalyzed by transglutaminase for improving structural, rheological, emulsifying and gelation properties.

In present study, microbial transglutaminase (MTGase) was applied to strengthen the interaction between casein and hempseed protein (HPI) through crosslinking. The structural and functional characteristics of this heteropolymers were investigated. Both homologous and heterologous crosslinking were achieved by adding MTGase in casein-HPI system, and thus enhanced zeta potential, surface hydrophobicity, viscosity, emulsifying and gelation properties of the complex. However, HPI hindered the crosslinking due to unbalanced Lys/Gln ratios. Emulsifying and gelling properties were significantly correlated with the secondary structures. When MTGase activity was < 30 U/g or treatment time was < 2 h, the α-helix content decreased by 9% while the ß-sheet content increased by 12%, respectively, with MTGase activity and treatment time increase. The structural alterations resulted in the better emulsifying activity, gel networks and water holding capacity of the complex. This work represents a novel interaction mode between casein and HPI via MTGase to elevate functional properties of complex.

Virulence effector SidJ evolution in Legionella pneumophila is driven by positive selection and intragenic recombination.

Effector proteins translocated by the Dot/Icm type IV secretion system determine the virulence of Legionella pneumophila (L. pneumophila). Among these effectors, members of the SidE family (SidEs) regulate several cellular processes through a unique phosphoribosyl ubiquitination mechanism mediated by another effector, SidJ. Host-cell calmodulin (CaM) activates SidJ to glutamylate the SidEs of ubiquitin (Ub) ligases and to make a balanced Ub ligase activity. Given the central role of SidJ in this regulatory process, studying the nature of evolution of sidJ is important to understand the virulence of L. pneumophila and the interaction between the bacteria and its hosts. By studying sidJ from a large number of L. pneumophila strains and using various molecular evolution algorithms, we demonstrated that intragenic recombination drove the evolution of sidJ and contributed to sidJ diversification. Additionally, we showed that four codons of sidJ which are located in the N-terminal (NTD) (codons 58 and 200) and C-terminal (CTD) (codons 868 and 869) domains, but not in the kinase domain (KD) had been subjected to strong positive selection pressure, and variable mutation profiles of these codons were identified. Protein structural modeling of SidJ provided possible explanations for these mutations. Codons 868 and 869 mutations might engage in regulating the interactions of SidJ with CaM through hydrogen bonds and affect the CaM docking to SidJ. Mutation in codon 58 of SidJ might affect the distribution of main-chain atoms that are associated with the interaction with CaM. In contrast, mutations in codon 200 might influence the α-helix stability in the NTD. These mutations might be important to balance Ub ligase activity for different L. pneumophila hosts. This study first reported that intragenic recombination and positive Darwinian selection both shaped the genetic plasticity of sidJ, contributing to a deeper understanding of the adaptive mechanisms of this intracellular bacterium to different hosts.

Antimicrobial, antioxidant and physical properties of chitosan film containing Akebia trifoliata (Thunb.) Koidz. peel extract/montmorillonite and its application.

A novel active packaging film was prepared in this study that incorporated Akebia trifoliata (Thunb.) Koidz. peel extracts (APE) and montmorillonite (MMT) into chitosan (CH) films. Compared with the pure CH film, the CH/APE film showed significantly higher tensile strength, elongation at break, UV light resistance, and antibacterial activity; the CH/MMT film displayed significant increases in contact angle, antioxidant activity, oxygen permeability, and thermal stability. SEM and AFM analyses showed that the additions were well-distributed into the CH matrix, but MMT induced a more compact and rougher structure. The CH-based film formula was optimized using the single-factor test and Box-Behnken design and was 0.15% MMT, 0.15% APE, and 1.50% CH. Besides, the optimized coating was applied in the postharvest preservation of A. trifoliata fruits, which yielded a significant effect on the delaying crack and mature of the fruits during 35 days of storage at 5 °C.

Phosvitin-wheat gluten complex catalyzed by transglutaminase in the presence of Na2SO3: Formation, cross-link behavior and emulsifying properties.

Phosvitin (PSV) is considered as a good emulsifier, although it has a low proportion of hydrophobic regions and steric hindrance. Wheat gluten (WG) possesses excellent hydrophobicity and macromolecular network structure. In this work, WG was subjected to a series of Na2SO3 solution, followed by cross-linking with PSV under transglutaminase (TGase) catalyzation. The results showed that Na2SO3 could break disulfide bonds of WG and increase its solubility from 7.33% to 42.82% with 1200 mg/L of Na2SO3. Correspondingly, the cross-linking degree was significantly enhanced. Compared to PSV, the cross-linked PSV-WG exhibited a higher surface hydrophobicity and thermal stability, with a lower zeta potential and apparent viscosity. The emulsifying activity of PSV-WG reached 17.42, 20.63 and 20.28 m2/g with Na2SO3 concentration of 300, 600 and 900 mg/L, which were all higher than that of PSV (15.19 m2/g). This work provided a novel strategy to elevate emulsifying properties of PSV by cross-link reaction.

Is ERAS effective and safe in laparoscopic gastrectomy for gastric carcinoma? A meta-analysis.

BACKGROUND: It is still unclear whether enhanced recovery after surgery is effective and safe in laparoscopic gastrectomy for gastric carcinoma. METHODS: Cochrane library databases, Medline, Embase, and Pubmed were searched from January 1, 1986, to December 31, 2016. Randomized controlled trials (RCTs) comparing fast-track recovery with conventional recovery strategies in laparoscopic radical gastrectomy for gastric carcinoma were included. The main outcomes measured were postoperative hospital stay, time to first flatus, hospital charge, and overall complication rate. RESULTS: Six RCTs with 400 patients were included in this study. Fast-track surgery has shorter postoperative hospital stays (weighted mean difference (WMD) - 2.65; 95% CI, - 4.01 to - 1.29, z = 3.82, P < 0.01) and less hospitalization expenditure (WMD - 523.43; 95% CI, - 799.79 to - 247.06, z = 3.71, P < 0.01) than conventional recovery strategies. There was no significant difference with respect to duration to first flatus (WMD - 17.72; 95% CI, - 39.46-4.02, z = 1.60, P = 0.11) and complication rate (OR 1.57; 95% CI, 0.82-2.98, z = 1.37, P = 0.17). CONCLUSIONS: Enhanced recovery after surgery is effective and safe and is thus recommended in laparoscopic radical gastrectomy for gastric carcinoma.

Pilot study analyzing automated ECG screening of hypertrophic cardiomyopathy.

BACKGROUND: Hypertrophic cardiomyopathy (HCM) is one of the leading causes of sudden cardiac death in athletes. However, preparticipation ECG screening has often been criticized for failing to meet cost-effectiveness thresholds, in part because of high false-positive rates and the cost of ECG screening itself. OBJECTIVE: The purpose of this study was to assess the testing characteristics of an automated ECG algorithm designed to screen for HCM in a multi-institutional pediatric cohort. METHODS: ECGs from patients with HCM aged 12 to 20 years from 3 pediatric institutions were screened for ECG criteria for HCM using a previously described automated computer algorithm developed specifically for HCM ECG screening. The results were compared to a known healthy pediatric cohort. The studies then were read by trained electrophysiologists using standard ECG criteria and compared to the results of automated screening. RESULTS: One hundred twenty-eight ECGs from unique patients with phenotypic HCM were obtained and compared with 256 studies from healthy control patients matched in 2:1 fashion. When presented with the ECGs, the non-voltage-based algorithm resulted in 81.2% sensitivity and 90.7% specificity. A trained electrophysiologist read the same data according to the Seattle Criteria, with 71% sensitivity with 95.7% specificity. The sensitivity of screening as well as the components of the ECG screening itself varied by institution. CONCLUSION: This pilot study demonstrates a potential for automated ECG screening algorithms to detect HCM with testing characteristics similar to that of a trained electrophysiologist. In addition, there appear to be differences in ECG characteristics between patient populations, which may account for the difficulties in universal screening.

An iOS-based Cepstral Peak Prominence Application: Feasibility for Patient Practice of Resonant Voice.

OBJECTIVES/HYPOTHESIS: Patients participating in voice therapy often express difficulty replicating therapy targets during their independent home practice. To assist patients, an iOS-based app was developed that calculates and displays cepstral peak prominence (CPP) values for patient self-monitoring of voice quality. The purpose of this study was to investigate the usability (ie ease of use) and utility (ie helpfulness) of this app in patient practice of resonant voice, and its effect on self-efficacy for practice. DESIGN: This study used mixed methods including repeated measures, survey, and semi-structured interview. METHODS/RESULTS: A total of 14 individuals undergoing voice therapy for a variety of voice disorders produced sustained phonation and connected speech tasks in three sequential conditions: habitual voice quality, resonant voice quality achieved without clinician assistance, and resonant voice quality achieved in interaction with the CPP app. For both tasks, CPP values were significantly and progressively higher in subsequent conditions, indicating utility of mobile CPP to differentiate habitual voice quality from resonant voice production. The participants found the app easy to use as indicated by high System Usability Scale ratings, and rated self-efficacy for practice with the app significantly higher than for unassisted practice. The interviews suggested that the participants found numeric CPP feedback helpful in self-evaluating voice quality, and thought it was "fun" to use the app. CONCLUSION: CPP information provided on a mobile app has potential to assist and motivate patients in the achievement of resonant voice production.

Electrocardiography Screening for Hypertrophic Cardiomyopathy.

BACKGROUND: Hypertrophic cardiomyopathy (HCM) is the leading cause of sudden cardiac death in athletes. However, preparticipation electrocardiogram (ECG) screening has been criticized for failing to meet cost-effectiveness thresholds, in part because of high false-positive rates. We sought to evaluate whether a highly automated software algorithm could be used for a high throughput, population-based screening program and address several of the limitations seen with population-based screening METHODS: A proprietary computed algorithm was created based on both voltage- as well as Seattle-based ECG criteria. Different cut points for Q-wave depth, Q-wave length, the degree of ST depression, the degree of T-wave inversion, and left ventricular voltage were analyzed for optimum sensitivity and specificity. After developing receiver operating characteristic curves for each criterion, different cut points were trialed together on our data set to obtain settings to optimize sensitivity and specificity. RESULTS: The automated algorithm was capable of identifying patients with HCM based on ECG with 88.6% sensitivity and 98% specificity, compared to a sensitivity of 90.2% and specificity of 96% when the ECGs were read by physicians according to the Seattle Criteria. Adding voltage criteria improved the sensitivity of the algorithm with a mild decrease in specificity. Optimum sensitivity with this automated software was 98%; optimum specificity was 96%. CONCLUSION: Computer-automated ECG screening for HCM is feasible. Evaluation of automated ECG algorithms in larger and more diverse populations is warranted.

[Cross-sectional study of characteristics and prognosis of patients with familial gastric cancer].

OBJECTIVE: To screen and collect the familial gastric cancer (FGC) kindreds for exploring its clinicopathological characteristics and prognosis. METHODS: A cross-sectional study was performed among 3640 patients with gastric cancer at 5 hospitals in Guangdong province between 2000 and 2007 and FGC kindreds were diagnosed according to the Amsterdam criteria. Their pedigree features and cancer incidence were analyzed. Clinical characteristics and prognosis were compared between FGC and sporadic gastric cancer (SGC) patients. Survival curves and overall five-year survival rates were established according to the Kaplan-Meier and Log-rank methods. Hazard ratios for death were calculated by Cox regression analysis. RESULTS: A total of 112 FGC kindreds (3.1%) were diagnosed among 3640 gastric cancer patients. In these 112 FGC families, 182 malignant tumors were diagnosed in the first- and second-degree relatives. Gastric cancer (n = 154, 84.6%), esophageal cancer (n = 8, 4.4%) and lung cancer (n = 6, 3.3%) were most common tumors. Tumor types in male proband families did not differ from those in female counterparts (P = 0.644). Most tumors occurred in the first-degree relatives and the ratio of male-to-female was 106:44. The mean age of FGC patients at 54 years was 10 years younger than that of SGC patients. No differences existed in tumor size, tumor location, Borrmann type, pT or pN between the FGC and SGC patients. The overall 5-year survival was 56.0% for FGC patients and 48.8% for SGC patients. Univariable (P = 0.287) and multivariable (HR = 1.101, P = 0.807) analyses demonstrated that FGC was not a significant prognostic factor. CONCLUSIONS: Gastric cancer is the most common cancer in FGC families. The first-degree male relatives are at a high risk of developing gastric cancer. Not particular clinical characteristics but pedigree examination facilitates the diagnosis of FGC.

[Value of spiral CT plus endoscopic ultrasonography (EUS) and spiral CT plus PET-CT in the preoperative assessment of gastric cancer invasion to the pancreas].

OBJECTIVE: To evaluate the value of EUS and PET-CT in combination with spiral CT in preoperative assessment of gastric cancer invasion to the pancreas. METHODS: Sixty advanced gastric cancer patients with suspected pancreatic invasion detected by spiral CT were selected in this study. All the 60 cases were then examined by EUS and 14 of them by PET-CT. The results were compared and evaluated with the findings during surgical operation and pathological results. RESULTS: The rate of correct preoperative diagnosis of pancreatic invasion by spiral CT in advanced gastric cancer patients was 63.3%, with an overdiagnosis rate of 36.7%. The diagnostic accuracy was increased to 87.8% and overdiagnosis reduced to 7.3%, when combined with EUS. There was a significant difference in diagnostic accuracy between spiral CT alone and spiral CT combined with EUS (P<0.01), but no significant difference between spiral CT alone and spiral CT combined with PET-CT (P>0.05). Spiral CT-EUS was more valuable in assessment of tumor location and invasion than PET-CT (P<0.01). CONCLUSION: The accuracy of spiral CT alone in the preoperative assessment of advanced gastric cancer with invasion to the pancreas is not high enough yet at present. Spiral CT combined with EUS can provide more accurate information on the tumor location, invasion site and extent of gastric cancer invasion to the pancreas, and reduce the overstaging rate caused by spiral CT alone. However, spiral CT combined with PET-CT does not show such improvement significantly.

[Associations of E-cadherin gene (CDH1) and hereditary gastric cancer in China].

OBJECTIVE: To investigate the protein expression, methylation promoter, somatic and germ-line mutations of E-cadherin gene (CDH1) in hereditary gastric cancer in China and to investigate its possible roles. METHODS: Eight probands diagnosed with ICG-HGC criterion were enrolled in our database from June 1994 to October 2007. Tumor tissues were detected for CDH1 expression by using immunohistochemistry (IHC) methods. CDH1 DNA sequencing was performed for all its 16 exons both in tumor and normal tissues of the same patients to detect somatic and germ-line mutations. Methylation promoter study was performed by using specific primers and polymerase chain reaction (PCR) methods. RESULTS: IHC analysis confirmed that the CDH1 expression was negative in 7 probands and downregulated in the other on proband. Six mutations in five probands were found with DNA sequencing: two silent mutations and four missense mutations. All six mutations were absent in normal tissues, thereby excluded its presence in germ-line cells. Both DNA missense mutations and gene silencing through promoter methylation was found in 4 probands. Two probands has only promoter methylation and one proband had only silent mutation. No DNA missense mutations or promoter methylation was found in one proband. CONCLUSIONS: CDH1 gene germ-line mutations are relatively rare in hereditary gastric cancer in China, and whereas CDH1 somatic mutations and promoter methylation synergistically induce CDH1 downregulation in these patients.

Comparison of patients by family history with gastric and non-gastric cancer.

AIM: To compare the gastric cancer (GC) patients by their family history with gastric and non-GC. METHODS: Positive family histories within second-degree relatives and clinicopathological features were obtained for 256 patients. RESULTS: Of the 256 probands, 112 (76 male, 36 female) were incorporated into familial GC (FGC) group: at least two GC members; 144 (98 male, 46 female) were included in the non-FGC group (relatives only affected with non-GCs). Of 399 tumors in relatives (181 from FGC against 212 from non-FGC), GC was the most frequent, followed by esophageal, hepatocellular, and colorectal cancer. Nasopharyngeal cancer was next to lung cancer but prior to breast and urogenital cancers. Most affected members aggregated within first-degree relatives (FGC: 66 siblings, 48 fathers, 31 mothers, four offspring; non-FGC: 56 fathers, 55 siblings, 43 mothers, and 15 offspring). The ratio of males to females in affected first-degree relatives was usually higher in male probands. Paternal history of GC was a slight risk for GC in males (OR = 1.19, 95% CI: 0.53-2.69), while risk of GC by maternal history of non-GCs was increased in females (OR = 0.46, 95% CI: 0.22-0.97). Diffuse-GC was the major histological type in all subgroups. Difference in tumor sites between the two groups was derived from an excess of upper sites in non-FGC female probands. CONCLUSION: Distribution of associated non-GCs in a family history of GC may vary with geographic areas. GC may have different genetic and/or environmental etiology in different families, and a certain subtype may be inherited in a female-influenced fashion.

Alcohol dehydrogenase-2 and aldehyde dehydrogenase-2 genotypes, alcohol drinking and the risk of primary hepatocellular carcinoma in a Chinese population.

OBJECTIVE: To investigate the relationship of alcohol dehydrogenase-2 (ADH2) and aldehyde dehydrogenase-2 (ALDH2) genotypes as well as alcohol drinking to the susceptibility of primary hepatocellular carcinoma (HCC). METHODS: A case-control study including 208 cases of HCC and 208 controls matched with sex, age and residential area was carried out in Taixing city of Jiangsu province, China. Blood samples were collected and tested for ADH2 and ALDH2 genotypes by PCR-RFLP method. RESULTS: There were no significant differences in the frequency of either ADH2 or ALDH2 genotypes between cases and controls. Compared with no-drinkers possessing ALDH21*1 genotypes, drinkers with ALDH21*2 or ALDH22*2 genotypes and cumulative amount of alcohol consumption >3 (Kg * years) were at a significantly higher risk of developing HCC (OR=3.30, 95%CI: 1.24-8.83). In contrast, there was no significant difference in cancer risk between no-drinkers with ADH21*1 and drinkers with ADH2 1*2 or ADH22*2 genotypes. A dose-dependent positive result was found (P=0.044) between cumulative amount of alcohol consumption and the risk of HCC in individuals carrying ALDH21*2 or ALDH22*2 genotypes. Drinkers with cumulative amount of alcohol consumption >3 (Kg * years) who possessed both inactive ALDH2 (ALDH21*2 or ALDH22*2) and inactive ADH (ADH21*2 or ADH22*2) genotypes were not at a significantly higher risk of HCC (adjusted OR=4.26, 95%CI: 0.63-29.08) compared to no-drinkers possessing ADH21*1 and ALDH21*1 genotypes. Compared with individuals possessing ALDH21*1, with negative HBsAg and cumulative amount of alcohol consumption 3 (Kg * years) had a significantly higher risk of HCC (OR=49.71, 95%CI: 5.51-448.96). CONCLUSION: These results revealed that it was not ADH2 but ALDH2 polymorphisms that had a significant interaction with heavy alcohol consumption in the development of HCC. This result suggests that to help lower their risk for HCC , persons with ALDH21*2 or ALDH22*2 genotypes should be encouraged to reduce their consumption of alcoholic beverages.

Methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C polymorphisms and the risk of primary hepatocellular carcinoma (HCC) in a Chinese population.

OBJECTIVES: Methylenetetrahydrofolate reductase (MTHFR), which is expressed in the liver, may be involved in both DNA methylation and DNA synthesis. It is also indicated as a potential risk factor of liver cancer in patients with chronic liver disease. To date, no study has been conducted on MTHFR and hepatocellular carcinoma (HCC) using a population-based design. The objective of this study was to evaluate the effects of polymorphisms of the MTHFR gene on the risk of primary liver cancer and their possible effect modifications on various environmental risk factors. METHODS: A population-based case-control study was conducted in Taixing, China. MTHFR C677T and A1298C were assayed by PCR-RFLP techniques. RESULTS: The frequency of MTHFR 677 C/C wild homozygotes genotype was 25.8% in cases, which was lower than that in controls (34.5%). The adjusted odds ratios (ORs) for the MTHFR 677 C/T and T/T genotype were 1.66(95% CI: 1.06-2.61), 1.21(95% CI: 0.65-2.28) respectively when compared with the MTHFR 677 C/C genotype. Subjects carrying any T genotype have the increased risk of 1.55(95% CI: 1.01-2.40) for development of primary hepatocellular carcinoma. A high degree of linkage disequilibrium was observed between the C677T and A1298C polymorphisms, with the D' of 0.887 and p < 0.01. The MTHFR 677 any T genotype was suggested to have potentially more than multiplicative interactions with raw water drinking with p-value for adjusted interaction of 0.03. CONCLUSION: We observed that the MTHFR 677 C/T genotype was associated with an increased risk of primary liver cancer in a Chinese population. The polymorphism of MTHFR 677 might modify the effects of raw water drinking on the risk of primary hepatocellular carcinoma.