Validation of genetic case-control studies in AIDS and application to the CX3CR1 polymorphism

New polymorphisms have been recently identified in CX3CR1, a coreceptor for some HIV-1 strains, one of which was associated with a strong acceleration of HIV disease progression. This effect was observed both by a case-control study involving 63 nonprogressors (NP) from the asymptomatic long-term (ALT) cohort and Kaplan-Meier analysis of 426 French seroconverters (SEROCO cohort). These results prompted us to analyze these polymorphisms in 244 nonprogressors (NPs) and 80 rapid progressors (RPs) from the largest case-control cohort known to date, the GRIV cohort. Surprisingly, the genetic frequencies found were identical for both groups under all genetic models (p >.8). The discrepancy with the previous work stemmed only from the difference between GRIV NPs versus ALT NPs. We hypothesized this might be due to the limited number of NPs in ALT (n = 63) and in this line we reanalyzed the data previously collected on GRIV for over 100 different genetic polymorphisms: we effectively observed that the genetic frequencies of some polymorphisms could vary by as much as 10% (absolute percentage) when computing them on the first 50 NP subjects enrolled, on the first 100, or on all the NPs tested (240 study subjects). This observation emphasizes the need for caution in case-control studies involving small numbers of subjects: p values should be low or other control groups should be used.However, the association of the CX3CR1 polymorphism with progression seems quite significant in the Kaplan-Meier analysis of the SEROCO cohort (426 individuals), and the difference observed with GRIV might be explained by a delayed effect of the polymorphism on disease. Further studies on other seroconverter cohorts are needed to confirm the reported association with disease progression.

Genetic heterogeneity and molecular epidemiology of GB virus C/hepatitis G virus in China

OBJECTIVE

The inter- and intrapatient genetic variation of GB virus C (GBV-C)/hepatitis G virus (HGV) was investigated to characterize the molecular epidemiologic profile of GBV-C/ HGV infection in China, an area endemic for viral hepatitis. The intrapatient variation of hepatitis C virus (HCV) from the same patients was compared to that of GBV-C/HGV.

STUDY DESIGN/METHODS

GB virus C/HGV RNA was amplified by polymerase chain reaction in 88 patients with hepatitis C, hepatitis B or presumed non-A-E hepatitis from three cities in China. Five clones of the GBV-C/HGV NS3 region were sequenced from each GBV-C/HGV RNA-positive patient. The corresponding region of HCV was also sequenced from patients co-infected with HCV. Representative sequences of the GBV-C/HGV NS3 region from each patient and those of isolates from other continents were subjected to phylogenetic analyses.

RESULTS

GB virus C/HGV was detected in 22 (25.25%) of 88 patients: 9 (21.4%) of 42 patients with presumed non-A-E hepatitis, 10 (27.7%) of 36 patients with hepatitis C, 3 (30.0%) in 10 patients with hepatitis B and C, and in none of 60 volunteer blood donors. The extent of nucleotide variation was less between Chinese isolates (2.4-17%; median, 10.4%) than between Chinese isolates and seven isolates from outside China (10.5-19.5%; median, 15.3%). Intrapatient sequence variation ranged from 0 to 1.75%, with a mean of 0.57 +/- 0.51%. Phylogenetic analysis grouped most Chinese isolates into four geographically specific clusters with a divergence of 10% to 16% from each other. The ratio of nonsynonymous to synonymous substitutions of GBV-C/HGV (Ka/Ks 0.019) was much lower than for HCV (0.071) in the same patients.

CONCLUSION

Chinese isolates of GBV-C/HGV are genetically distinct. There are local strains as well as shared strains between different locales. The extent of amino acid sequence conservation suggests strong selection against nonsynonymous substitutions in the GBV-C/HGV genome.

Familial aggregation of stroke volume and cardiac output during submaximal exercise: the HERITAGE Family Study

Familial aggregation of stroke volume (SV) and cardiac output (Qc by CO2 rebreathing) at 50 Watts (W) and 60 % of maximal oxygen uptake (VO2max) as well as their changes in response to a 20-week endurance exercise training program was assessed in 99 Caucasian families who participated in the HERITAGE Family Study. In order to interpret familial influences independent of effects of age, sex, and body size (indexed by body surface area here), SV and Qc levels were adjusted for these primary parameters prior to genetic analysis within four sex-by-generation groups (the responses to training were additionally adjusted for their baseline values). Maximal heritabilities for baseline SV, Qc, and their changes in response to training during the two stages of submaximal exercise were estimated using a familial correlation model. At 50W, maximal heritabilities reached 41% and 42% for baseline SV and Qc, respectively, and were 29% and 38% for the respective responses to training. At 60% of VO2max, maximal heritabilities reached 46 % for baseline SV and Qc, and were 24% and 30% for the respective responses to training. Generally there were no meaningful differences between the maximal heritabilities at 50 W and 60% of VO2max. However, the maximal heritabilities for the baseline were slightly higher than the estimates for the changes in response to training. Based upon results arising from these non-obese, non-hypertensive, and sedentary families, we found that SV and Qc at 50 W and 60% of VO2max as well as their changes in response to the 20-week endurance exercise training were moderately heritable. Not only genetic determinants but also familial non-genetic factors might attribute to the observed patterns of familial aggregation of SV and Qc during submaximal exercise in the present study.

[Study on hepatitis C virus infection of peripheral blood mononuclear cells in chronic hepatitis C patients]

OBJECTIVE

To demonstrate HCV infection and replication in the peripheral blood mononuclear cells (PBMCs) of hepatitis patients by the methods of molecular biology, immunology and electron microscopy.

METHODS

HCV RNA and antigens were detected in the PBMCs of 28 patients with chronic hepatitis C by RT-PCR, Immunohistochemistry and electron microscopy, respectively.

RESULTS

The positive rate of HCV RNA and HCV antigens were 77.27% (17/22) and 75.00% (21/28), respectively. Two types of spherical HCV-like particles with diameter of approximately 65 nm and 110 nm were observed in cytoplasmic vesicles by electron microscopy in the PBMCs with high titer of HCV RNA and antigens in 10 patients. The budding and shedding of these particles could also be found in the cytoplasmic vesicles. Immunoelectron microscopy using antibodies against HCV core and NS(3) demonstrated that the particles contained HCV antigens.

CONCLUSION

HCV can infect and replicate in the PBMCs of patients with chronic hepatitis C.

[Expression of thymidylate synthase gene and recurrence of colorectal carcinoma: their relation and clinical significance]

OBJECTIVE

To study the relationship between expression of thymidylate synthase (TS) gene and recurrence of colorectal carcinoma and its effect on clinical treatment.

METHODS

RT-PCR was used to detect the expression of TS gene in primary foci, para-tumoral intestine mucosa, local recurrence, abdominal-pelvic dissemination and hepatic metastasis in 68 cases of colorectal carcinoma, and TS protein was examined with western blot.

RESULTS

In 68 cases of colorectal carcinoma, the expression of TS gene in primary foci was 22.1% (15/68); and the positive rates of TS gene expression in local recurrence, abdominal-pelvic dissemination and hepatic metastasis were 88.5% (23/26), 85.0% (17/20), 40.9% (9/20) respectively. The rates of TS protein expression in primary foci, local recurrence, abdominal-pelvic dissemination and hepatic metastasis were 22.1% (15/68), 84.6% (22/26), 80.0% (16/20), 36.4% (8/22) respectively. The negative expression of TS gene and TS protein was detected in paratumoral intestinal mucosa. The results of TS gene and TS protein expression were identical with those the two methods. The positive rates of TS gene and TS protein expression in diversified recurrence foci and metastasis were higher than those in primary foci (P < 0.01). The differences of TS gene and TS protein expression rates between recurrence and hepatic metastasis were significant (P < 0.01). The expression rates of TS gene and TS protein in local recurrence and abdominal-pelvic dissemination tissues were higher than those in hepatic metastasis.

CONCLUSION

Overexpression of TS gene plays an important role in the process of local recurrence and abdominal-pelvic dissemination of colorectal carcinoma.

Influence of CCR5 promoter haplotypes on AIDS progression in African-Americans

OBJECTIVES

To test the hypothesis that the CCR5 promoter variants in HIV-1-infected African-Americans affect the rate of progression to AIDS and to determine the extent of linkage disequilibrium between the CCR5P1 allele and the CCR5 59029A variant (referred to here as CCR5-2459A), both of which have been shown independently to accelerate AIDS progression in Caucasians.

DESIGN

We used survival analysis to assess the effects of CCR5 promoter variants in HIV-1 seroincident Caucasians and African-Americans.

SUBJECTS AND METHODS

Genotypes were determined for 806 Caucasians and 1067 African-Americans, which included 700 seroconverters, enrolled in four HIV/AIDS natural history cohort studies. These genotypes were used to determine linkage and haplotypes for CCR2 and CCR5 alleles. Survival analysis was used to assess the effect of CCR2, CCR5, and CCR5 promoter haplotypes on progression to AIDS in seroincident African-Americans.

RESULTS

A survey of Caucasians and African-Americans demonstrated complete linkage disequilibrium between CCR5P1 and CCR5-2459A sites. The composite CCR5P1 haplotype (including the CCR5-2459A allele) is shown to be associated with rapid progression to AIDS endpoints in both African-American and Caucasian cohorts, but the effect is recessive in Caucasians and dominant in African-Americans. This is probably due to the presence of modulating genes or as yet unidentified polymorphisms that may differ between racial groups.

A genetic study of sex hormone--binding globulin measured before and after a 20-week endurance exercise training program: the HERITAGE Family Study

Familial aggregation and a major gene effect were assessed for baseline serum sex hormone-binding globulin (SHBG) levels and the response (post-training minus baseline) to a 20-week endurance training program in a selected sample of 428 non-obese nonhypertensive individuals from 99 white families who were sedentary at baseline in the HERITAGE Family Study. Baseline SHBG levels were not normally distributed, and were therefore logarithmically transformed prior to genetic analyses. In a sample without postmenopausal mothers, maximal (genetic and familial environmental) heritabilities were 50% averaged across sexes, 73% in men, 50% in women, and 31% in men versus women for the age-body mass index (BMI)-adjusted baseline. The estimate reached 64% when the baseline was further adjusted for the effects of estradiol, fasting insulin, and testosterone levels. For the response to training, no sex difference was found and the heritability reached about 25% to 32%. Segregation analysis was separately performed in the whole sample and in the sample without postmenopausal mothers. In addition to a multifactorial effect for both the baseline and the response to training, a major effect for the baseline appeared to be familial environmental in origin, whereas a major effect for the response to training was Mendelian in nature. The major gene effect for the response to training in the whole sample was undetectable in the sample without postmenopausal mothers, and it is therefore possible that the postmenopausal mothers, characterized by decreased sex hormones with or without estrogen replacement therapy for menopause, produced some confounding effects. In addition, the reduced sample size might also be a plausible candidate explanation. The novel finding in this study is that baseline SHBG levels and the response to training were influenced by a multifactorial effect with sex difference for the baseline. The response to training appeared to be additionally influenced by a single recessive locus that is independent of baseline SHBG levels.

Complex segregation analysis of blood pressure and heart rate measured before and after a 20-week endurance exercise training program: the HERITAGE Family Study

Complex segregation analysis of baseline resting blood pressure (BP) and heart rate (HR) and their responses to training (post-training minus baseline) were performed in a sample of 482 individuals from 99 white families who participated in the HERITAGE Family Study. Resting BP and HR were measured at baseline and after a 20-week training program. Baseline resting BP and HR were age-adjusted and age-BMI-adjusted, and the responses to training were age-adjusted and age-baseline-adjusted, within four gender-by-generation groups. This study also analyzed the responses to training in two subsets of families: (1) the so-called "high" subsample, 45 families (216 individuals) with at least one member whose baseline resting BP is in the high end of the normal BP range (the upper 95th percentile: systolic BP [SBP] > or = 135 or diastolic BP [DBP] > or = 80 mm Hg); and (2) the so-called "nonhigh" subsample, the 54 remaining families (266 individuals). Baseline resting SBP was influenced by a multifactorial component (23%), which was independent of body mass index (BMI). Baseline resting DBP was influenced by a putative recessive locus, which accounted for 31% of the variance. In addition to the major gene effect, which may impact BMI as well, baseline resting DBP was also influenced by a multifactorial component (29%). Baseline resting HR was influenced by a putative dominant locus independent of BMI, which accounted for 31% of the variance. For the responses to training, no familiality was found in the whole sample or in the nonhigh subsample. However, in the high subsample, resting SBP response to training was influenced by a putative recessive locus, which accounted for 44% of the variance. No familiality was found for resting DBP response to training. Resting HR response to training was influenced by a major effect (accounting for 35% of the variance), with an ambiguous transmission from parents to offspring.

Segregation analysis of apolipoproteins A-1 and B-100 measured before and after an exercise training program: the HERITAGE Family Study

Complex segregation analyses of apolipoproteins (apo) A-1 and B-100 were performed in a sample of 520 individuals from 99 white families who participated in the HERITAGE Family Study. In these sedentary families, plasma apo A-1 and B-100 concentrations were measured before and after a 20-week endurance exercise training program. Baseline apo A-1 and B-100 were adjusted for the effects of age (age-adjusted baseline apo A-1 and B-100) and for the effects of age and BMI (age-BMI-adjusted baseline apo A-1 and B-100). The change in response to training was computed as a simple Delta (posttraining minus baseline) and was adjusted for age and the baseline (age-baseline-adjusted apo A-1 and B-100 responses to training). In the present study, a major gene could not be inferred for baseline apo A-1. Rather, we found a major effect along with a multifactorial effect accounting for 8% to 9% and 51% to 56% of the variance, respectively. In addition, no clear evidence supported a major-gene effect for its response to training, whereas the transmission of a major effect from parents to offspring was ambiguous, ie, genetic in nature or familial environmental in origin. The major effect accounted for 15% of the variance, with an additional 21% and 58% of the variance being accounted for by a multifactorial effect in parents and offspring, respectively. It is interesting to have obtained evidence of a putative recessive major locus for baseline apo B-100, which accounted for 50% to 56% of the variance, with an additional 25% to 29% of the variance due to a multifactorial effect. In contrast, no major effect for its response to training was identified, although a multifactorial effect was found that accounted for 27% of the variance. The novel findings arising from the present study are summarized as follows. Baseline apo A-1 and its response to training were influenced by a major effect and a multifactorial effect. Baseline apo B-100 was influenced by a putative major recessive gene with a multifactorial component, but its response to training was influenced solely by a multifactorial component in these sedentary families.

A genetic study of dehydroepiandrosterone sulfate measured before and after a 20-week endurance exercise training program: the HERITAGE Family Study

Familial aggregation and possible major gene effects were evaluated for the baseline serum dehydroepiandrosterone sulfate (DHEAS) level and the change in DHEAS in response to a 20-week exercise training program in a sample of 481 individuals from 99 Caucasian families who were sedentary at baseline and who participated in the HERITAGE Family Study. Baseline DHEAS levels were not normally distributed, and were therefore logarithmically transformed and adjusted for the effects of age and sex prior to genetic analysis. The DHEAS response to training was computed as the simple difference, post-training minus baseline, and was adjusted for the baseline DHEAS level, age, and sex. Maximal (genetic and familial environmental) heritabilities (using a familial correlation model) reached 58% and 30% for the baseline and the response to training, respectively. Our estimate for the baseline is generally in agreement with previous reports, suggesting that the magnitude of the familial effect underlying this phenotype in these sedentary families is similar to that in the general population. However, segregation analysis showed no evidence for a multifactorial familial component in data for either the baseline or the response to training. Rather, a major additive gene controlling the baseline was found. For the response to training in the complete sample, transmission of the major effect from parents to offspring was ambiguous, but in a subset of 56 "responsive" families (with at least 1 family member whose response to training was greater than 1 standard deviation) this major effect was Mendelian in nature. The putative major genes accounted for 50% and 33% of the variance for the baseline and the response to training, respectively. The novel finding in this study is that the baseline DHEAS level and the change in DHEAS in response to training may be influenced by major gene effects.

Genomic scan for maximal oxygen uptake and its response to training in the HERITAGE Family Study

This study aimed to identify human genomic regions that are linked to maximal oxygen uptake (VO(2 max)) in sedentary individuals or to the responsiveness of VO(2 max) to a standardized endurance training program. The results of a genomic scan based on 289 polymorphic markers covering all 22 pairs of autosomes performed on the Caucasian families of the HERITAGE Family Study are presented. The mean spacing of the markers was 11 cM, and a total of 99 families and 415 pairs of siblings were available for the study. VO(2 max) in the sedentary state was adjusted for the effects of age, sex, body mass, fat mass, and fat-free mass, whereas the VO(2 max) response was adjusted for age and baseline level of the phenotype. Two analytic strategies were used: a single-point linkage procedure using all available pairs of siblings (SIBPAL) and a multipoint variance components approach using all the family data (SEGPATH). Results indicate that linkages at P values of 0.01 and better are observed with markers on 4q, 8q, 11p, and 14q for VO(2 max) before training and with markers on 1p, 2p, 4q, 6p, and 11p for the change in VO(2 max) in response to a 20-wk standardized endurance training program. These chromosomal regions harbor many genes that may qualify as candidate genes for these quantitative traits. They should be investigated in this and other cohorts.

[The significance of detection of hepatitis C virus RNA in peripheral blood mononuclear cells of patients with chronic hepatitis C]

OBJECTIVE

To determine the role of peripheral blood mononuclear cells (PBMCs) in hepatitis C virus (HCV) infection.

METHODS

HCV RNA, HCV antigen and Fas antigen were detected in PBMCs of 22 patients with chronic hepatitis C, 21 renal dialysis patients with anti-HCV positive and 12 health blood donors as normal controls. All specimens were studied by electronic microscope (EM).

RESULTS

(1) The positive rate of HCV RNA in PBMCs of 22 patients with hepatitis C was 77.3% (17/22). (2) EM showed that HCV particles replicated in PBMCs of the patients with HCV infection, but not in the serum of patients with negative HCV RNA and healthy controls. (3) HCV RNA were positive both in the serum and PBMCs of 8 patients with HCV particles positive and had a close relationship with HCV antigen and Fas antigen. The expression of HCV and apoptosis were found in the cytoplasm of PBMCs in these 8 patients.

CONCLUSION

(1) Hepatitis C virus could replicate in PBMCs and produce infectious HCV particles. (2) HCV in PBMCs may act as the source of reinfection for HCV and lead to persistent infection and recurrence.

Familial aggregation of VO(2max) response to exercise training: results from the HERITAGE Family Study

The aim of this study was to test the hypothesis that individual differences in the response of maximal O(2) uptake (VO(2max)) to a standardized training program are characterized by familial aggregation. A total of 481 sedentary adult Caucasians from 98 two-generation families was exercise trained for 20 wk and was tested for VO(2max) on a cycle ergometer twice before and twice after the training program. The mean increase in VO(2max) reached approximately 400 ml/min, but there was considerable heterogeneity in responsiveness, with some individuals experiencing little or no gain, whereas others gained >1.0 l/min. An ANOVA revealed that there was 2.5 times more variance between families than within families in the VO(2max) response variance. With the use of a model-fitting procedure, the most parsimonious models yielded a maximal heritability estimate of 47% for the VO(2max) response, which was adjusted for age and sex with a maternal transmission of 28% in one of the models. We conclude that the trainability of VO(2max) is highly familial and includes a significant genetic component.

Familial aggregation of resting blood pressure and heart rate in a sedentary population: the HERITAGE Family Study. Health, Risk Factors, Exercise Training, and Genetics

The familial aggregation of resting systolic blood pressure (SBP), diastolic blood pressure (DBP), and heart rate (HR) was assessed in 98 white families, who participated in the HERITAGE Family Study, and were selected to be sedentary, and primarily nonobese and normotensive. In the present study, 522 family members were sedentary at baseline examination, and resting SBP, DBP, and HR measured during this examination were investigated. If physical activity level is a potent environmental factor, then we expected that the relative contribution of environmental factors to the familial aggregation of blood pressure (BP) would be somewhat reduced, because activity was controlled for in this study. Using a familial correlation model, maximal heritabilities were estimated to be 54%, 41%, and 32% for resting SBP, DBP, and HR, respectively, in these families; and they were 51%, 42%, and 34% for resting SBP, DBP, and HR, respectively, when the data were adjusted for body mass index. The estimates are somewhat higher for BP but similar for HR to those reported in previous family studies, suggesting that the distribution of the underlying etiologic factors in these sedentary families may be similar to those in the general population. There was substantial spouse resemblance in this study, which may be explained by a higher concordance for correlated lifestyle factors including diet, similar activity levels, or by assortative mating for relative weight or dietary preferences.

[Study of the relation between mutant gene in bile and hepatic metastasis of large intestinal carcinoma]

OBJECTIVE

To study the value of point mutant genes in the diagnosis of hepatic metastasis of large intestinal carcinoma.

METHODS

Techniques of PCR-SSCP and DNA sequencing were used to detect point mutations of p53 and k-ras genes in primary focus, hepatic metastatic focus, and bile.

RESULTS

50 cases of large intestinal cancer were detected. 38 cases (76.0%) had p53 and k-ras gene mutations. p53 gene mutations were detected in 28 cases (56.0%) and k-ras gene mutations in 16 cases (32.0%). The same point mutant genes in bile with primary focus were detected in 10 out of 12 patients with hepatic metastasis (83.3%).

CONCLUSIONS

The tumor cells of hepatic metastasis show the same clonal origin with primary focal cells that had same point mutant genes. Detection of the point mutant genes in bile is of value in the diagnosis of hepatic metastasis of large intestinal carcinoma.

A pharmacoeconomic analysis of topical therapies for patients with mild-to-moderate stable plaque psoriasis: a US study

Psoriasis is a persistent skin disorder characterized by abnormal keratinocyte differentiation, keratinocyte hyperproliferation, and increased expression of inflammatory markers at the cellular level, leading to erythema, induration, and scaling of the skin. Depending on the severity of the disease, annual outpatient costs range from $1400 to $6600 per patient, totaling $3.2 billion each year in the United States. Because the disease is persistent and progressive, patients receiving a diagnosis of psoriasis early in life can expect to require lifelong care, which translates into lifelong expense. Treatments include topical formulations, systemic therapies, phototherapies, and combination therapies. Of these, topical agents are the first-line treatments, including fluocinonide and other steroids, calcipotriene, and tazarotene, a once-daily retinoid. To establish the relative cost-effectiveness of these drugs (fluocinonide, calcipotriene, and tazarotene), we conducted a pharmacoeconomic study from the perspective of a third-party payer, using a decision-analytic model validated by clinical experts. Data were drawn from a meta-analysis of the contemporary medical literature. Clinical success, clearing, and relapse rates determined the probabilities for therapeutic outcomes and the number of anticipated disease-free days for each study comparator. Costs for physician visits, drug acquisition, laboratory testing, and adverse-events management were added to each branch of the decision tree and multiplied by the appropriate probabilities to establish the expected cost of treatment, stratified by the primary treatment choice. Cost-effectiveness was expressed as the total expected cost of achieving a disease-free day. Tazarotene 0.1% was 16.74% more cost-effective than tazarotene 0.05%, 85.46% more cost-effective than fluocinonide, and 143.75% more cost-effective than calcipotriene. The expected cost of achieving a disease-free day was $49.46 for tazarotene 0.1%, $57.74 for tazarotene 0.05%, $91.73 for fluocinonide, and $120.56 for calcipotriene. Treatment with tazarotene offers an opportunity to reduce the cost of care for patients with mild-to-moderate psoriasis and enhance patient satisfaction by gaining more disease-free days.

Evolutionary analysis of the 5'-terminal region of hepatitis G virus isolated from different regions in China

We have determined the nucleotide sequence of the 5'-terminal region of the hepatitis G virus (HGV) genome in 11 hepatitis patients from three cities in China. Phylogenetic analyses revealed that the Chinese isolates were genetically distinct from previously described West African isolates (type 1) and American, European and East African isolates (type 2), with a mean sequence divergence of approximately 10%. The mean divergence between isolates from Lanzhou, in the northwest of China, and those from Shanghai and Nanjing, on the east coast of China, was 5% (range 3-7%). The isolates from Shanghai and Nanjing were closely related to a common strain in Japan, while some of those from Lanzhou were closely related to a southeast Asian type 3 isolate. Thus, the Chinese isolates belong to the type 3 variant of HGV.

[Improvement of the assay for pre-S2 Ag/Ab detection and its application in different patients]

A new ELISA inhibition test for measuring serum Pre-S2Ab was developed to avoid the "double positive" phenomenon. One hundred and twenty samples with Pre-S2Ab negative were detected for Pre-S2Ab, the critical range for Pre-S2Ab in normal population was confirmed: a positive result was decided while the inhibition ration was over 50%, a negative result was decided while the inhibition ratio was less than 34%, and a dubious result was decided while the ratio was over 34% but less then 50%. At the same time, serum samples from sixty patients with chronic hepatitis B were detected for Pre-S2Ag and Pre-S2Ab, it showed that (1) the positive ratio of HBV DNA in patients with Pre-S2Ag positive was much higher than in patients with Pre-S2Ag negative (P < 0.01); (2) to the 46 patients with HBV DNA positive, Pre-S2Ag had a better relationship with HBV DNA than the HBeAg/Ab did (P < 0.01). Furthermore, to patients with acute hepatitis B, the presence of Pre-S2Ab was closely related to the prognosis of the disease, and the Pre-S2Ab assay could also be used to evaluate the preventive effect of HB vaccine containing Pre-S2Ag.

Infection with GB virus C and hepatitis C virus in hemodialysis patients and blood donors in Beijing

RNAs of GB virus C (GBV-C) and hepatitis C virus (HCV) were sought by reverse-transcription polymerase chain reaction with nested primers deduced from the 5' untranslated region: 79 patients on maintenance hemodialysis, 205 commercial blood donors, and 205 voluntary donors in Beijing were studied. GBV-C RNA was detected in 43 (54%) patients and 17 (8%) commercial donors, and HCV RNA in 43 (54%) patients and 13 (6%) commercial donors, respectively. By contrast, GBV-C RNA was detected only in 2 (1%) and HCV RNA in none among 205 volunteer blood donors serving as controls. Thus both patients and commercial blood donors were at higher risk for infection with GBV-C (P < 0.001) than controls. HCV RNA was detected more often in patients with GBV-C RNA than without (29/43 or 67%, vs. 14/36 or 39%, P < 0.05) as well as in commercial donors with GBV-C RNA than without (5/17 or 29% vs. 8/188 or 4%, P < 0.01). A phylogenetic tree constructed on a sequence of 100 base pairs in the helicase region indicated that GBV-C isolates from Beijing are more similar to Japanese isolates than to isolates from the United States and Africa. Sequences from certain hemodialysis patients and those from some commercial donors were similar, suggesting nosocomial infection and spread among restricted groups.

Infection with GB virus C and hepatitis C virus in hemodialysis patients and blood donors in Beijing

RNAs of GB virus C (GBV-C) and hepatitis C virus (HCV) were sought by reverse-transcription polymerase chain reaction with nested primers deduced from the 5' untranslated region: 79 patients on maintenance hemodialysis, 205 commercial blood donors, and 205 voluntary donors in Beijing were studied. GBV-C RNA was detected in 43 (54%) patients and 17 (8%) commercial donors, and HCV RNA in 43 (54%) patients and 13 (6%) commercial donors, respectively. By contrast, GBV-C RNA was detected only in 2 (1%) and HCV RNA in none among 205 volunteer blood donors serving as controls. Thus both patients and commercial blood donors were at higher risk for infection with GBV-C (P < 0.001) than controls. HCV RNA was detected more often in patients with GBV-C RNA than without (29/43 or 67%, vs. 14/36 or 39%, P < 0.05) as well as in commercial donors with GBV-C RNA than without (5/17 or 29% vs. 8/188 or 4%, P < 0.01). A phylogenetic tree constructed on a sequence of 100 base pairs in the helicase region indicated that GBV-C isolates from Beijing are more similar to Japanese isolates than to isolates from the United States and Africa. Sequences from certain hemodialysis patients and those from some commercial donors were similar, suggesting nosocomial infection and spread among restricted groups.

Effect of extended parietal cell vagotomy on long-term nutrition and digestive function

OBJECTIVE

To study the effect of extended parietal cell vagotomy (EPCV) on long-term nutritional status and digestive-absorption function.

PATIENTS AND METHODS

Thirty-six patients undergoing EPCV were compared with 30 patients with subtotal gastrectomy (SG) 7-14 years after operation. The patients were evaluated in terms of nutritional status, gastric secretion, gastrointestinal motility, and intestinal digestive-absorption function.

RESULTS

The nutritional status was generally less satisfactory in 33.3% patients with anemia after SG and body weight decreased in 54%. The patients after EPCV were all in good nutritional status, and had no symptoms of anemia; 56% of them had body weight increased by more than 3 kg. The mean basal acid output (BAO), maximal acid output (MAO), and peak acid output (PAO) of the EPCV group were significantly reduced after operation (P < 0.01), and moderately reduced as compared with those of the control group (P > 0.05). But the BAO, MAO, and PAO of the SG group were more markedly reduced than those of the control group (P < 0.001) before operation. Vitamin B12, folacin, intrinsic factor and iron protein level of serum in the EPCV group were slightly decreased as compared with those of the control group (P > 0.05), but more significantly decreased in the SG group than in the control group (P < 0.001). Iron protein and intrinsic factor level was lower than the normal level. The gastric emptying time and small intestinal passthrough time of EPCV were more close to the normal physiological status, but in the SG group, they were significantly fast (P < 0.001). The results of intestinal D-xylose absorption test in EPCV and SG groups were similar (P > 0.05).

CONCLUSIONS

EPCV is capable of preserving gastric acid of physiologic level and normal digestion-absorption function. The effect of EPCV on long-term nutrition and digestion absorption function was extremely milder than that of SG. Therefore, a theoretical basis is provided for the rationality of EPCV.

Ultrastructure of parietal cells before and after extended parietal cell vagotomy in patients with duodenal ulcer and their complications

Since 1979 we have treated 149 patients with duodenal ulcer by extended parietal cell vagotomy (EPCV). Electron microscopy of parietal cells from gastric body mucosa and gastric acid secretory test were carried out in 22 randomly selected patients before and after EPCV. It was shown that before EPCV the ultrastructure of parietal cells presented the feature of vigorous section identical to the hyperfunctional secretion of gastric acid. The ultrastructure of parietal cells presented the feature of acute depression of secretory function, which was identical to a significant reduction of secretory function of gastric acid 0.5-6 months after EPCV. Two to 10 years after operation, however, especially over 10 years after EPCV, the ultrastructural changes of parietal cells gradually returned to normal, but gastric acid secretion remained at a low level, without preoperative secretory capacities. The results of this study provide a histological basis for the application of extended parietal cell vagotomy in the treatment of duodenal ulcer and its complications.

[Long-term effect of extended parietal cell vagotomy on patients' nutrition and digestive function]

In this study, 36 patients undergoing extended parietal cell vagotomy (EPCV) were compared with 30 patients with subtotal gastrectomy 7-14 years after surgery. The patients' nutritional status, gastric sectretion, gastrointestinal motility and intestinal absorption function were evaluated. The nutritional status was generally less satisfactory in 33. 3% patients with anaemia after gastrectomy and decrease of body weight in 54%. The patients after EPCV were all in good nutritional status, with no anemia; 56% of them had a body weight increase of more than 3kg. Therefore, the rationality of EPCV was estalished.

Viral, host and environmental risk factors for hepatocellular carcinoma: a prospective study in Haimen City, China

To identify specific environmental, viral, and genetic risk factors for hepatocellular carcinoma (HCC) and the interaction of such factors, we are conducting a prospective study in a high-incidence area of China. Questionnaires were completed and biosamples collected by 60,984 men ages 30-64 years, at study entry. Within 2.5 years, 183 deaths from HCC had occurred. Each HCC case was matched with 5 controls and compared for items on the questionnaire. In addition to chronic hepatitis B virus (HBV) infection, the significant risk factors were: occupation (peasant), corn consumption (in the 1970s), family history of HCC, and history of an episode of acute hepatitis as an adult. HBV, consumption of aflatoxins, a genetic factor, and possibly a second hepatitis virus infection contribute to the risk of HCC.

[Anti-HBs-F(ab)'2 to the seroconversion of HBsAg carriers]

The exogenous anti-HBs-F(ab)'2 was given to the HBsAg carriers for the study of its effect of seroconversion in vivo. 30 HBsAg carriers, with a duration of 2-15 years (HBeAg positive 18 and anti-HBe positive 12) were studied after intramuscular infection of anti-HBs-F(ab)'2. In the HBeAg group, the cut off value of HBeAg decreased significantly (P < 0.01) in 18 carriers, of which 6 seroconversed to anti-HBe, all the HBe-Ag carriers had a high S/N ratio of anti-HBs-anti-Id (RIA) but after 12-week treatment the ratio decreased significantly (P < 0.01). Six of 18 HBV DNA positive carriers conversed to negative (33%) and 8 of 13 DNA-P positive conversed to negative (61%). 12 anti-HBe positive carriers showed no seroconversion.

Extended parietal cell vagotomy in the treatment of perforation, hemorrhage and stenosis due to duodenal ulcer

Ninety-five patients with perforation, hemorrhage or stenosis due to duodenal ulcer were treated by extended parietal cell vagotomy. Postoperative follow-up ranged from 3.5 to 10 years (mean 6 years) in 88 patients (92%) with acute perforation (60), hemorrhage (8) and stenosis (20). There was no operative mortality. Ulcer recurrence was 2.3%. Only one patient (5%) had restenosis and required reoperation. There was no recurrent hemorrhage and there were few long-term complications. According to the Visick classification, 67 patients (76%) belonged to grade I, 13 (14.7%) grade II, 4 (4.5%) grade III, and 4 (4.5%) grade IV. Extended parietal cell vagotomy proved to be safe with excellent results, low ulcer recurrence and few complications. Moreover, recurrent ulcers healed rapidly following medical therapy. The authors believe that extended parietal cell vagotomy should be the treatment of choice for acute perforation, hemorrhage or stenosis due to duodenal ulcer.