Deoxyribonucleic acid amplification and hybridisation in Crohn''s disease using a chlamydial plasmid probe.

The possibility that Crohn's disease is caused by infection with Chlamydia trachomatis was examined by probing for chlamydial plasmid deoxyribonucleic acid (DNA) in DNA extracts from Crohn's disease tissue and by means of a serological study. Gut DNA extracts were obtained from 10 patients with Crohn's disease and four control subjects and were probed with a chlamydial plasmid probe after Southern blotting. The polymerase chain reaction was also used to amplify any chlamydial plasmid DNA present in tissue DNA extracts, before Southern blotting and probing. Chlamydial proctitis control specimens were not available: gut DNA extracts mixed with traces of chlamydia plasmid served as positive controls. Using these techniques, no chlamydial plasmid DNA sequences were found in Crohn's disease tissue. An enzyme linked immunosorbent assay for C trachomatis LI was performed on 48 patients with Crohn's disease and 48 control subjects. Seropositivity was present in 14.6% of patients and 29% of control subjects and was not statistically significant (p greater than 0.05). The failure to show chlamydial DNA and the lack of serological response to chlamydia make C trachomatis infection a very unlikely factor in the pathogenesis of Crohn's disease.     

The effects of cardiopulmonary bypass and cold cardioplegia on coronary flow velocity and the reactive hyperemic response in patients and dogs

In normal coronary arteries, reactive hyperemic responses to a 20-second occlusion, an index of coronary reserve, usually demonstrate a peak-to-resting flow velocity ratio of 4:1 or more. Most intraoperative studies that have assessed reactive hyperemic responses in bypassed vessels have reported peak-to-resting flow velocity ratios of 2:1 or less following a 20-second occlusion. These decreased reactive hyperemic responses could be due to coronary vasodilatation after cardiopulmonary bypass or to an inadequate physiological result of the surgical procedure. In 14 patients with angiographically normal coronary arteries, the peak-to-resting flow velocity ratio following a 20-second coronary occlusion decreased significantly (p less than 0.05) from 4.4 +/- 0.2 (mean +/- standard error) before bypass to 3.0 +/- 0.3 after bypass. In a similar dog model, the peak-to-resting flow velocity ratio decreased by 36 to 52% during the first hour following one hour of cardiopulmonary bypass and cardioplegia. During the same period, left ventricular perfusion increased 21 to 30%, mean arterial pressure and coronary vascular resistance decreased, and myocardial oxygen consumption was unchanged. In a second group of dogs studied for the effects of duration (200 to 240 minutes) of anesthesia and thoracotomy alone, peak-to-resting flow velocity ratio was significantly lower. These clinical and experimental studies suggest that major coronary vasodilatation occurs early following cardiopulmonary bypass and cold cardioplegia, and may contribute to the blunted coronary reactive hyperemic responses reported during this time. Consequently, an intraoperative peak-to-resting flow velocity ratio of 3:1 for bypassed coronary arteries may represent an excellent physiological result.     

A review of intra-articular knee injuries in racquet sports diagnosed by arthroscopy

Because of the recent rapid increase in the number of knee injuries related to racquet sports, the authors undertook a retrospective study of such injuries seen over a 5-year period at the Toronto Western Hospital Sports Medicine Institute. The 121 patients who presented over the study period with a racquet-sports-related knee injury requiring arthroscopy represented 30% of all racquet-sports related injuries seen during that period. The mean age at presentation was 32.8 years and two-thirds of the patients were men. All the major racquet sports were represented. In all, 213 lesions (7 bilateral) were seen at 128 arthroscopies, and 165 arthroscopic procedures were performed. The most common lesion was meniscal followed by chondromalacia patellae, anterior cruciate ligament tears, chondral lesions and pathologic plicae. Over 90% of the patients returned to their chosen racquet sport within 3 months of the arthroscopy and most were playing at a similar performance level to that before the initial injury.     

Infants thinner at birth exhibit smaller kidneys for their size in late gestation in a sample of fetuses with appropriate growth

Fetal ultrasound measurements were employed to investigate the relationship between weight and ponderal index at birth and kidney size during the second (23 weeks) and third (32 weeks) trimesters of pregnancy in a sample of 25 normally growing fetuses. Kidney volume and kidney volume / fetal weight ratio at 32 weeks are significantly and positively related to both weight and ponderal index at birth, controlling for sex, gestational age at birth, and day of ultrasound measurement. A second‐degree polynomial relationship approximates the predictability of kidney volume fetal weight ratio at 23 weeks to that at 32 weeks, demonstrating shifting growth rates in fetal organ and body growth relationships during midgestation. Sex and parental size are suggested as contributing to these patterns. Females have a surge in renal growth between 23 and 32 weeks to catch up to earlier growing males, and maternal weight significantly predicts incremental growth in kidney volume and the kidney volume / fetal weight ratio at 32 weeks of gestation. The observation that fetuses relatively thin at birth have relatively smaller kidneys for their size in late gestation suggests that the influence of maternal weight on birth outcome may act through organ growth. Am. J. Hum. Biol. 14:398–406, 2002. © 2002 Wiley‐Liss, Inc.     

Pituitary volume in pediatric obsessive-compulsive disorder.

BACKGROUND: Abnormalities in the limbic-hypothalamic-pituitary-adrenal (LHPA) axis have been implicated in the pathogenesis of obsessive-compulsive disorder (OCD). To our knowledge, however, no prior study has measured pituitary gland volume in OCD. METHODS: Volumetric magnetic resonance imaging studies were conducted in 31 psychotropic drug-na?ve children (10 boys, 21 girls) aged 8-17 years and 31 case-matched healthy comparison subjects. RESULTS: Pituitary volume was significantly smaller in patients with OCD as compared with healthy control subjects (11% smaller). Smaller pituitary volume in patients with OCD was associated with increased compulsive but not obsessive symptom severity. Boys with OCD had smaller pituitary gland volumes compared with control boys (20% smaller). No significant differences in pituitary volume were observed between girls with OCD and control girls. Boys with OCD had significantly smaller pituitary volumes than girls with OCD (31% smaller), whereas control boys also had smaller pituitary gland volumes compared with control girls (21% smaller). CONCLUSIONS: These findings provide new evidence of reduced pituitary volume in pediatric OCD that seems to be more prominent in male patients. The observed alterations in pituitary volume are consistent with neuroendocrine studies that have reported abnormalities in the LHPA axis in OCD.     

Healthy choices: motivational enhancement therapy for health risk behaviors in HIV-positive youth.

This study piloted a brief individual motivational intervention targeting multiple health risk behaviors in HIV-positive youth aged 16-25. Interviews about sexual behavior and substance use and viral load testing were obtained from 51 HIV-positive youth at baseline and post intervention. Youth were randomized to receive a four-session motivational enhancement intervention (N = 25) or to a wait-list control (N = 26). Of the eligible youth approached, 88% agreed to participate, and 80% percent of participants completed at least three of four sessions. The treatment group showed significantly greater reductions in unprotected sex acts and in viral load compared with controls. Although change scores for substance use were not significantly different between the two groups, paired t tests demonstrated that reductions in alcohol use and marijuana use were significant for the treatment group at the trend level. There were no significant differences in substance use from baseline to posttest for the control group. Findings demonstrate the potential of a brief motivational enhancement intervention to improve health risk behaviors in HIV-positive youth. Larger randomized clinical trials are warranted. Resources required for retention should not be underestimated.