Notes: The relationship between Helicobacter pylori infection and gastric carcinoma remains controversial, especially in the African setting where infection is common, while gastric cancer is perceived to be uncommon, the basis of the so called ‘African enigma’. This discrepancy between infection and the development of disease is commonly attributed to differences in host, environment and bacterial factors. Interest in the bacterial factors has focused on heterogeneity in the so-called ‘virulence genes’.〈section xml:id="abs1-3"〉〈title type="main"〉Aim.The aim of this prospective, case-controlled study was to establish whether H. pylori infection is significantly associated with gastric cancer and to investigate whether gastric cancer is associated with genotypically distinct (as it relates to the candidate virulence genes) organisms in this population.〈section xml:id="abs1-4"〉〈title type="main"〉Methods.Patients with histologically confirmed gastric cancer were matched with nonulcer dyspeptic controls for age (within 5 years), gender and ethnicity. Helicobacter pylori status was determined by RUT, histology, culture and serology (locally validated and used as default determinant of H. pylori status). Tumors were classified according to the Lauren classification. The ‘virulence genotype’ of 17 paired culture samples was determined by previously described and validated molecular techniques (cagA presence, vacA alleles, structure of the cag pathogenicity island and analysis of the iceA alleles). Categorical variables were analysed by the χ2 test.〈section xml:id="abs1-5"〉〈title type="main"〉Results.Forty-eight patients (median age 59 years) could be adequately matched to controls. 39/48 (81%) cases and 43/48 (90%) controls were H. pylori positive (NS). Significant differences in the virulence genotypes of infecting strains were noted: vacAs2-controls 24%, cases 0%, p 〈 .00001; vacAs1 present – cases 100%, controls 76%, p 〈 .05; cagA-3′-length 〉 650 bp – cases 47%, controls 0%, p 〈 .002; cag pathogenicity island intact – cases 82%, controls 43%, p 〈 .04; iceA1 – cases 53%, controls 6%, p 〈 .005. cagA was found in all subjects.〈section xml:id="abs1-6"〉〈title type="main"〉Conclusion.This study indicates that, in this African population at least, there is no difference in the prevalence of H. pylori infection when comparing gastric cancer cases with matched controls. However, the findings suggest that gastric cancer may be associated with infection by organisms that are genotypically different from those not associated with disease.

Notes: Objective To determine whether routine testing for serum Chlamydia trachomatis antibodies, considered in combination with a woman's clinical features, may avoid the need for diagnostic laparoscopy in routine investigation for infertility.Design Retrospective case notes analysis.Setting Secondary level care infertility clinic.Population Eighty women who had undergone both laparoscopy and serum Chlamydia trachomatis antibody testing.Methods Ascertainment of any history of suspected pelvic inflammatory disease, pelvic pain, cervical intraepithelial neoplasia, pelvic surgery or appendicectomy; any abnormality on clinical pelvic examination; the findings at laparoscopy; the result of serum Chlamydia trachomatis antibody testing by enzyme-linked immunosorbent assay (ELISA) screening with microimmunofluorescence (MIF) confirmatory diagnostic testing. The usefulness of clinical features, the serum Chlamydia trachomatis antibody test and these two variables combined in the detection of tubal disease and pelvic pathology of relevance to infertility were measured statistically.Main outcome measures Specificity, sensitivity, positive predictive value, negative predictive value and likelihood ratio for each of the tests.Results The combination of any positive clinical feature with a positive test for serum Chlamydia trachomatis antibodies detects tubal disease with sensitivity 92%, specificity 70%, positive predictive value 72%, negative predictive value 91% and likelihood ratio 3.1; it detects bilateral tubal obstruction with sensitivity 84%, specificity 51%, positive predictive value 35%, negative predictive value 91% and likelihood ratio 1.7; it detects pelvic pathology relevant to infertility with sensitivity 76%, specificity 71%, positive predictive value 80%, negative predictive value 65% and likelihood ratio 2.6. The negative predictive value for pelvic pathology from the use of clinical features in addition to the chlamydia antibody test is not significantly higher than that from the chlamydia antibody test alone (53%).Conclusions A policy of selective laparoscopy in routine investigation for infertility, based on the result of the test for serum Chlamydia trachomatis antibodies and a woman's clinical features, is not supported.

Notes: A high performance liquid chromatography (HPLC) method was developed by using gradient elution with acetonitrile as a mobile phase to reduce the time required for determination of ATP, ADP, AMP, IMP, HxR and Hx. The method was then applied to investigate nucleotide degradation in herring kept in ice and MAP (60% CO2/40% N2).

Notes: A rapid high-performance liquid chromatographic (HPLC) method for the determination of nine biogenic amines and trimethylamine (TMA) was developed. A derivatization procedure is reported. It involves dissolving benzoyl chloride in acetonitrile to enhance its reaction with biogenic amines. This was compared with benzoyl chloride dissolved in methanol and with only benzoyl chloride to find the optimal condition for benzoylation of biogenic amines in terms of time and derivatization conditions. A gradient elution system was used for analysis with a mixture of acetonitrile and HPLC grade water and took less than 7 min to complete the analysis. The application of this method to detect biogenic amines in herring stored at 2 ± 2 °C and in modified atmosphere packing (MAP) was investigated. The concentrations of amines in herring held at 2 ± 2 °C increased more rapidly than herring stored in MAP. The level of TMA in herring held at 2 ± 2 °C was higher than herring stored in MAP. No significant differences were found in histamine concentrations between herring stored at 2 ± 2 °C and in MAP during the early stages of storage period but there was a significant difference (P 〈 0.05) after 6 days of storage. Significant differences were found (P 〈 0.05) in concentrations of putrescine (after 6 days) and cadaverine (after 4 days) between herring held at 2 ± 2 °C and in MAP.

Notes: Major quality parameters, such as muscle composition, fat deposition, muscle fatty acid composition and external appearance were studied in wild and cultured gilthead sea bream. Muscle fat content and total depot fat (peritoneal and perivisceral fat) indicated a seasonal variation with minimum values observed in late spring and maximum in late summer. Gonadosomatic indices of cultured fish were lower than those found in wild specimens. Lipid content of cultured sea bream was much higher than that of wild fish. Differences were also observed in fatty acid profiles. Cultured fish were characterized by higher levels of monoenes, n-9 and 18:2n-6 fatty acids and wild fish by higher levels of saturates, 20:4n-6, n-3 fatty acids and n-3/n-6 ratios. Differences were also noted in the external appearance of fish.