Background:
Serologic screening of gastric cancer (GC) by serum pepsinogens (sPG) levels and Helicobacter pylori (Hp) sero-status, though highly informative, has provided heterogeneous results. Here, we have evaluated the modifying effects of demographic factors on the risk impact of Hp sero-status/sPG levels in gastric cancer, with particular emphasis on age.Methods:
A cross-sectional study was carried out on 1341 individuals (GC = 578, healthy = 763), who were stratified into two age groups: 35-59 years (middle-aged, n = 830) and ≥ 60 years (60 years-plus, n = 511). Demographic factors and serological states (Hp sero-staus and sPG levels) were recorded by subject interview and serum ELISAs, respectively. Covariate-specific odds ratios were calculated by multivariable logistic regression.Results:
Hp infection was consistently associated with increased sPGI and sPGII levels in the 60 year-plus, but not the middle-aged group. The joint examination of the variable states of the three serum biomarkers (Hp serology, sPGI, and sPGI/II ratio), in the 60 year-plus age group, demonstrated a stepwise escalation of risk from the single (sPGIlow; OR = 2.6), to double (sPGIlow/sPGI/IIlow; OR = 3.55, and Hppositive/sPGIlow; OR = 5.0) and ultimately triple (Hppositive/PGIlow/PGI/IIlow; OR = 10.48) positive states, in reference to the triple negatives. However, this pattern was not exhibited in the middle-aged subjects.Conclusion:
Age was clearly identified as a modifying factor on the risk projection of the combined states of Hp serology and sPG levels in gastric cancer screening, reflected by the augmented (~10.5 fold) risk of GC in the triple positive (Hppositive/sPGIlow/sPGI/IIlow) 60 year-plus subjects, which was not evident in the middle-aged group. Key Words: Biomarkers, Demography, Age Distribution 相似文献Background
Attempts for early detection of gastric cancer have recently focused on host''s genetic susceptibility factors and gene-environment interactions. We have, herein, studied the association of MTHFR C677T single nucleotide polymorphism (SNP) and its interaction with Helicobacter pylori infection, smoking, age and gender on the risk of gastric cancer among an Iranian population.Methods
Gastric cancer patients (n = 450) and cancer-free controls (n = 780) were studied for serum H. pylori-specific IgG antibodies by ELISA and MTHFR C677T polymorphism (SNP) by PCR-RFLP. Demographic and life style data were collected through patient interviews. Unconditional logistic regression model estimated odds ratio (OR) and the corresponding 95% confidence intervals (CI).Results
The interactions of MTHFR genotype with H. pylori infection (P = 0.03), age (P = 0.049) and gender (P = 0.007) were statistically significant. Accordingly, MTHFR C677T carriers who were also positive for H. pylori infection exhibited 80% (OR = 1.8, 95% CI = 1.0-2.9) significant excess risk of non-cardia gastric cancer. Furthermore, subjects over the age of 50 or female subjects carrying MTHFR C677T SNP showed 40 (OR = 1.4, 95% CI = 1.0-2.0) and 100 (OR = 2.0, 95% CI = 1.2-3.2) percent increased risk of gastric cancer, respectively.Conclusion
MTHFR C677T SNP seems to increase the risk of gastric cancer and the effect is significantly inflated by interactions with H. pylori infection, age and gender. Key Words: Helicobacter pylori, Smoking, Gender identity, Age group, Methylenetetrahydrofolate reductase 相似文献The aim of the present study was to evaluate the effects of hCG injections on reproductive efficiency by hCG treatment in both male or female brooders of domesticated pikeperch (Sander lucioperca) in the first generation. The study consisted of four treatments based on hormone injection to male or female brooders including T1: both sexes were injected, T2: only females were injected, T3: only males were injected, and T4: without hormone injection. Each treatment which included 14 males and 12 females were introduced to a single rectangular concrete tank with one spawning nest for each mate (a total of 12 nests per tank). Fish were injected by a single dose of 200 IU/kg hCG before transferring to mating tanks. After mating, nests containing fertilized eggs were transferred to circular concrete tanks for incubation and hatching of embryos. According to the results, treatments T3 and T4 did not respond to hormonal stimulation and no fish were spawned. Treatments T1 and T2 showed a positive response to hormone injection. Latency time, fertilization rate, and hatching rate showed no significant difference between T1 and T2 (P?>?0.05), but the number of responded females was significantly higher in T2 (P?<?0.05). The results of the present study demonstrated that it is possible to perform the semi-artificial propagation of domesticated pikeperch via injecting with 200 IU/kg hCG just to females, without the need for hormonal stimulation for males.
相似文献