Enteric viruses and bacteriological parameters in molluscs

Eighty-seven samples of shellfish were collected considering: type of mollusc, origin, growing area, monitoring or for human purpose. The bacteriological parameters were: Fecal Coliforms, Escherichia coli, and Salmonella; whereas the virological parameters included: Hepatitis A and E virus, Rotavirus, Astrovirus and Enterovirus. In total, 63.2% of samples had normal bacteria values, only one sample was Salmonella positive. The percentage of positive samples for Hepatitis A virus was 5.7%, Rotavirus 29.9%, Astrovirus 27.6%, Enterovirus 10.3%. The recovery of hepatitis E virus was always negative, whereas 13 samples (14.9%) were positive for two viruses.     

Condom effectiveness for reducing transmission of gonorrhea and chlamydia: the importance of assessing partner infection status

This analysis examined the importance of differential exposure to infected partners in epidemiologic studies of latex condom effectiveness for prevention of sexually transmitted infections. Cross-sectional, enrollment visit data were analyzed from Project RESPECT, a trial of counseling interventions conducted at five publicly funded US sexually transmitted disease clinics between 1993 and 1997. The association between consistent condom use in the previous 3 months and prevalent gonorrhea and chlamydia (Gc/Ct) was compared between participants known to have infected partners and participants whose partner infection status was unknown. Among 429 participants with known Gc/Ct exposure, consistent condom use was associated with a significant reduction in prevalent gonorrhea and chlamydia (30% vs. 43%; adjusted prevalence odds ratio = 0.42, 95% confidence interval: 0.18, 0.99). Among 4,314 participants with unknown Gc/Ct exposure, consistent condom use was associated with a lower reduction in prevalent gonorrhea and chlamydia (24% vs. 25%; adjusted prevalence odds ratio = 0.82, 95% confidence interval: 0.66, 1.01). The number of unprotected sex acts was significantly associated with infection when exposure was known (p for trend < 0.01) but not when exposure was unknown (p for trend = 0.73). Restricting analyses to participants with known exposure to infected partners provides a feasible and efficient mechanism for reducing confounding from differential exposure to infected partners in condom effectiveness studies.     

Folate is associated with the natural history of high-risk human papillomaviruses

Several micronutrients have been implicated in cervical carcinogenesis. However, their mode of action is still a matter of speculation. In particular, it is unclear whether certain nutrients reduce the probability of acquiring high-risk human papillomavirus (HPV) or whether they facilitate the clearance of high-risk HPV. We conducted a 24-month prospective follow-up study to test the hypothesis that systemic concentrations of folate are associated with the occurrence and duration of high-risk HPV infections after controlling for other micronutrients (vitamins B(12), A, E, and C, total carotene) and known risk factors for high-risk HPV infections and cervical cancer. Circulating concentrations of these micronutrients and risk factors for cervical cancer were determined in a cohort of 345 women who were at risk of developing cervical intraepithelial neoplasia. Using the hybrid capture 2 (HC-2) assay, high-risk HPV status was evaluated at 6-month intervals up to 24 months. All women had at least three consecutive visit high-risk HPV test results. Higher folate status was inversely associated with becoming HC-2 test-positive [odds ratio (OR): 0.27; 95% confidence interval (CI), 0.08-0.91; P = 0.04]. Women with higher folate status were significantly less likely to be repeatedly HC-2 test-positive (OR: 0.33; 95% CI, 0.13-0.86; P = 0.02) and more likely to become test-negative during the study (OR: 2.50; 95% CI, 1.18-5.30; P = 0.02). To our knowledge, this is the first long-term prospective follow-up study reporting an independent protective role of higher folate status on several aspects of the natural history of high-risk HPV after controlling for known risk factors and other micronutrients. Improving folate status in subjects at risk of getting infected or already infected with high-risk HPV may have a beneficial impact in the prevention of cervical cancer.     

Mediastinal lymph nodes: relaxation time/pathologic correlation and implications in staging of lung cancer with MR imaging

The authors measured the T1 and T2 relaxation times of freshly excised human mediastinal lymph nodes to determine whether the times are clinically useful in distinguishing benign from malignant nodes. All measurements were performed at 20 MHz and 40 degrees C, within 45 minutes of lymph node excision. Mean T1 and T2 relaxation times of 99 benign nodes were 566 msec (standard deviation [SD], 117 msec) and 92 msec (SD, 29 msec), respectively. For the 16 malignant nodes, these times were 640 msec (SD, 138 msec) and 105 msec (SD, 26 msec), respectively (P less than .05 for difference in T1 times, P greater than .05 for difference in T2 times). Histograms showed considerable overlap in the relaxation times of benign and malignant nodes such that absolute measurement of these times will likely be of limited clinical value.     

Elastolytic activity among Aeromonas spp. Using a modified bilayer plate assay.

A total of 166 isolates of Aeromonas, representing diverse geographical regions and originating from various sources, were evaluated for the ability to produce elastase by using a bilayer elastin agar medium (BEAM) plate assay. The degree of elastase activity of individual strains was roughly assessed by measuring the clear area beneath or peripheral to the colony and recorded as 1+, 2+, or 3+. Of the 166 aeromonads tested, 53 (32%) were found to produce elastase, of which 26 (49%) were 3+, 21 (40%) were 2+, and 6 (11%) were 1+. All but one A. hydrophila (n = 45) were observed to produce elastase (98%). One of three A. schubertii strains as well as one isolate of Aeromonas group 501 were elastase positive. All 3+ elastolytic activity was associated with A. hydrophila only. Elastase activity was not detected even after prolonged incubation with A. veronii biogroup sobria (n = 26), A. caviae (n = 57), A. veronii biogroup veronii (n = 4), A. media (n = 1), and A. eucrenophila (n = 1). In addition to its value as a reliable indicator of elastase production for eventual use in virulence assays, we have found that the detection of elastase using the BEAM plate serves as a very useful phenotypic marker for the major, clinically important Aeromonas spp.     

Oral contraceptive use and the incidence of cervical intraepithelial neoplasia.

OBJECTIVE: Our objective was to examine the relationship between oral contraceptive use and the incidence of cervical intraepithelial neoplasia. STUDY DESIGN: In a prospective follow-up study of 6622 women participating in the Second Troms? Study conducted in 1979 and 1980 in Troms?, Norway, women aged 20 to 49 years answered a questionnaire regarding their smoking history, dietary habits, alcohol consumption, and oral contraceptive use. They were then followed for 10 years with data from the Pathology Registry of the University Hospital. RESULTS: The age-adjusted incidence rate of cervical intraepithelial neoplasia was 897 per 100,000 person years among noncurrent and 1295 per 100,000 person years among current oral contraceptive users as of 1979. After adjusting for age, marital status, smoking, and frequency of alcohol intoxication the relative rate for current users was 1.5 (95% confidence interval 1.1 to 2.1), and the relative rate for past users was 1.4 (95% confidence interval 1.0 to 1.8), as compared with those who had never used oral contraceptives before 1979. CONCLUSION: These findings support the hypothesis that the occurrence of cervical intraepithelial neoplasia is increased by oral contraceptive use.     

Motor-evoked potentials in masseter muscle by electrical and magnetic stimulation in intact alert man

The electromyographic responses of the masseter after different types of transcranial stimulation were recorded with surface and needle electrodes. Magnetic stimulation at 4 cm lateral to the vertex on the biauricular line elicited MEPs in the contralateral masseter (latency 6.9 ms) due to activation of motor cortex or adjacent elements along the cortico-nuclear pathway. The ipsilateral responses to the same stimuli and to more lateral ones had shorter latencies and were ascribed to direct stimulation of the trigeminal nerve, probably its intracisternal portion. This was also the probable origin of the ipsilateral MEPs after both anodic and cathodic bipolar electrical stimulation at 7 and 11 cm lateral to the vertex on the biauricular line.