Given a passage with a context and an answer, construct a question on the basis of the information present in the passage. Construct the question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) it answer uses text phrases from the passage. Avoid creating questions that (i) can't be answered correctly without actually understanding the passage and (ii) uses the same words or phrases given in the passage.

Context: Tumor necrosis factor-alpha (TNF-alpha) is a major pro-inflammatory cytokine. Recently, the G-308A polymorphism of the TNF-alpha gene has been associated with modified gene expression and increased TNF-alpha production in the -308A allele. We evaluated its influence on the incidence and clinical course of membranous glomerulonephritis.', 'We studied 53 patients with biopsy-proven primary membranous glomerulonephritis followed up for 5.7 +/- 4.9 years. 100 volunteers were analyzed as controls. According to the slope of the curve of reciprocal serum creatinine against time, group A (slow progressors, n = 35) and group B (fast progressors, n = 18) were defined. TNF-alpha G-308A polymorphism was determined by polymerase chain reaction amplification.', 'The frequency of the A-allele (associated with higher TNF-alpha levels) was significantly higher in patients than control subjects (patients: G-allele: 0.66, A-allele: 0.34; controls: G-allele 0.85, A-allele 0.15, p < 0.001). Similarly, the genotype distribution differed significantly between our study and control populations (patients: GG-genotype: 41.5%, GA: 49.1%, AA 9.4%; controls: GG: 71%, GA: 27%, AA 2%, p = 0.001). Age, renal function, proteinuria and blood pressure were similar at the time of renal biopsy between patients with different genotypes (NS). There was also a tendency towards an overpresentation of the A-allele in group B indicating a possible impact on the progression of membranous nephropathy, but a significance was not reached. Furthermore, no impact on renal survival in the Kaplan- Meier analysis was detected (NS).
Answer: Our results suggest that TNF-alpha gene G-308A polymorphism is a risk factor for the development of membranous glomerulonephritis.
Is tumor necrosis factor-alpha gene G-308A polymorphism a risk factor for the development of membranous glomerulonephritis?

Context: The clinical value of oesophageal histology in non-complicated gastro-oesophageal reflux disease (GORD) is controversial. Our aim was to explore the role of histology in preoperative diagnosis and postoperative follow-up in GORD.', 'From 40 patients 2 histopathologists graded and scored 191 oesophageal biopsies in a blinded manner to evaluate inter- and intraobserver variation pre- and postoperatively. Correlation between preoperative histology and objective clinical findings (endoscopy, esophageal 24-hour pH monitoring, and manometry) was calculated as well.', 'Pathologist I interpreted 16 (50%) preoperative biopsies as normal, 5 (16%) with mild, 4 (12.5%) moderate, and 7 (21.9%) severe reflux changes. Pathologist II interpreted 11 (35.5%) preoperative biopsies as normal, 11 (35.5%) with mild, 6 (19.4%) moderate, and 3 (9.7%) severe reflux changes. In preoperative biopsies, interobserver variation was 33.8% and intraobserver variation 9.7%. A positive correlation was detectable between preoperative endoscopic and morphologic findings; no correlation existed between either acid reflux or LES pressure and oesophageal morphology. Normal pH monitoring and fundic wrap were noted postoperatively in all cases. In postoperative histology no significant differences according to pathologist I existed when compared with preoperative changes: 22 normal (69%), 7 mild (22%), 1 moderate (3.1%), and 2 severe (6.3%). Compared to preoperative analysis, pathologist II interpreted 24 (77%, p = 0.001) of the postoperative findings as normal, 1 (3%, p = 0.003) as mild, 4 (12.9%, n.s.) as moderate, and 2 (6.5% n.s.) as severe reflux changes. In postoperative biopsies interobserver variation was 21.1% and intraobserver variation 5.6%.
Answer: The role of oesophageal histology in preoperative diagnosis and postoperative follow-up of GORD may be considered limited.
Is oesophageal histology in gastro-oesophageal reflux disease of minor pre- and postoperative diagnostic value?

Context: To summarise the present evidence for an association between circulating fibrinogen or D-dimer and presence of abdominal aortic aneurysm (AAA) presence.', 'MEDLINE database was searched to identify all case-control studies that compared plasma fibrinogen or D-dimer concentrations between patients with AAA and subjects without AAA. For each study, data regarding fibrinogen or D-dimer concentrations in both the AAA and control groups were used to generate mean differences (MDs) and 95% confidence intervals (CIs). Study-specific estimates were combined using inverse variance-weighted average of logarithmic MDs in both fixed- and random-effects models.', 'Our search identified 10 eligible studies including 834 cases with AAA and 6971 controls without AAA for fibrinogen and six studies including 264 patients with AAA and 403 subjects without AAA for D-dimer. Pooled analysis demonstrated significantly higher fibrinogen (fixed-effects MD, 0.37gl(-1); 95% CI: 0.30-0.44gl(-1)) and D-dimer (random-effects MD: 415.36ngml(-1); 95% CI: 128.97-701.76ngml(-1)) concentrations in the AAA group than those in the control group.
Answer: We found that plasma fibrinogen and D-dimer concentrations are likely to be higher in cases with AAA than control subjects. Higher plasma fibrinogen and D-dimer concentrations may be associated with the presence of AAA.

Are plasma fibrinogen and D-dimer concentrations associated with the presence of abdominal aortic aneurysm : a systematic review and meta-analysis?