Adherence of Staphylococcus aureus to cultures of human peritoneal mesothelial cells

Strains of Staphylococcus aureus, isolated from the effluentof patients with peritonitis on CAPD (continuous ambulatoryperitoneal dialysis), adhered well to both cultured human mesothelialcells and to fibronectin, but not to laminin or gelatin. Mesothelialcells grown in medium M199 exhibited more surface fibronectincompared to cells grown in MEM-Dval and demonstrated higherlevels of S. aureus adherence. Soluble fibronectin concentrations up to lOµg/ml increasedthe adherence of S. aureusto cultured mesothelial cells. Thedose-response curve was consistent with the binding of fibronectinto a saturable receptor of apparent dissociation constant (K_D)= 1.7xlO^–10 M. This corresponds closely to the K_D (2xlO^–10M) of the staphylococcal fibronectin-binding protein. S. aureus adherence was increased following the preincubationof mesothelial cell monolayers with interleukin-1 and was maximalafter 6 h preincubation. Treating mesothelial cells with interferon-gammafor 48–72 h reduced the adherence of S. aureus.     

Altered angiotensin-II receptors in human hepatocellular and hepatic metastatic colon cancers.

OBJECTIVE: To characterize angiotensin-II receptor density and affinity in normal and cirrhotic livers and in hepatocellular and metastatic colorectal cancer. SUMMARY BACKGROUND DATA: Several studies have indicated a possible beneficial effect of angiotensin-II as a biologic response modifier in the treatment of hepatic or metastatic colon cancer. This is based on evidence that angiotensin-II will cause a selective increase in arterial vasoconstriction in normal liver compared with tumor. METHODS: Human hepatoma (5), metastatic colon (10), or cirrhotic (3) liver was obtained. Non-tumor-bearing regions served as normal liver. Angiotensin-II receptor binding was determined on membranes with 125I-angiotensin-II and in situ studies were performed using the biotin-avidin detection system. RESULTS: Angiotensin-II receptor density was markedly down-regulated in tumor compared with normal or cirrhotic liver. CONCLUSIONS: A loss of angiotensin-II receptors occurs on the neovasculature of hepatic tumors.     

HERPES SIMPLEX VIRUS ENCEPHALITIS: PROBLEMS IN DIAGNOSIS

Six children aged 13 days to nine years with herpes simplex encephalitis (HSE) are presented. Institution of appropriate antiviral treatment was later than six days in three cases; original diagnosis in these cases were post-traumatic epilepsy, bacterial meningitis and febrile convulsion. Initially pyrexia was absent in two cases and cranial CT was normal in two cases. Encephalitic changes were observed on the EEGs of five children. Diagnosis was confirmed by paired serological titres, brain biopsy, vesicle culture and CSF titres. The outcome for all six children was poor. HSE should always be considered in children presenting with focal seizures, even when apyrexial and with normal CT findings. In such situations, saving CSF for antibody titres or antigen identification should be routine practice. Treatment with acyclovir is justified before precise virological diagnosis has been established.     

The effects of norepinephrine transporter inactivation on locomotor activity in mice.

BACKGROUND: Acute administration of different classes of antidepressants can enhance or reduce spontaneous locomotor activity in a novel environment, but the effects of chronic antidepressant treatment on spontaneous locomotor activity in novel and familiar environments are less well characterized. Because norepinephrine is an important regulator of spontaneous locomotor activity, we speculated that norepinephrine transporter blockade contributes to the effects of some antidepressants on spontaneous locomotor activity. METHODS: Antidepressant drugs (reboxetine, desipramine, imipramine, venlafaxine, bupropion) were administered acutely (intraperitoneal) or chronically (via osmotic minipump) to control and norepinephrine transporter knockout mice, and spontaneous locomotor activity in novel or familiar environments was recorded. RESULTS: Acute treatment with most norepinephrine transporter-blocking antidepressants decreased spontaneous locomotor activity in a novel environment, whereas chronic treatment decreased spontaneous locomotor activity in both novel and familiar environments. The exception was bupropion, a dual norepinephrine transporter/dopamine transporter blocker, which tended to increase spontaneous locomotor activity. Coadministration of reboxetine and the dopamine transporter blocker GBR 12909 also increased spontaneous locomotor activity. Norepinephrine transporter knockout mice had low basal spontaneous locomotor activity, which was increased by bupropion, whereas reboxetine had no effect in norepinephrine transporter knockout mice. CONCLUSIONS: Acute or chronic inactivation of the norepinephrine transporter decreases spontaneous locomotor activity in novel and familiar environments unless coupled with dopamine transporter blockade.     

Is there an association between self-reported warm-up behaviour and golf related injury in female golfers?

Golfing injuries have been shown to occur frequently, and injury countermeasures have been suggested to help reduce injury risk. Performing an appropriate warm-up is thought to reduce injury risk, however there is a lack of evidence to support this notion. Therefore this study aimed to investigate the relationships between warm-up participation and injury in a cohort of female golfers. A total of 522 golfers participating in the Victorian Women's Pennant Competition completed the study. Over one-third (35.2%) of the golfers reported having sustained a golfing injury within the previous 12 months, with the lower back the most commonly injured region. Most golfers reported not warming-up prior to play or practice. Golfers who reported not warming-up on a regular basis were more likely to have reported a golfing injury in the previous 12 months than those reporting frequent warm-up participation (OR=45.2; 95% CI: 13.5, 151.7). Less skilled golfers were also less likely to report sustaining a golfing injury than more skilled golfers (OR=0.2; 95% CI: 0.1, 0.5). This study is one of the few to establish an association between warm-up participation and injury. Further prospective studies are warranted to determine whether warm-up reduces injury risk for golf participation.     

Increased sensitivity of virus-infected cells to inhibitors of protein synthesis does not correlate with changes in plasma membrane permeability

Semliki Forest virus-infected BHK cells or herpes simplex virus-infected Vero cells were incubated with the protein synthesis inhibitors hygromycin B and gougerotin. Infected cells take up no more [3H]hygromycin or [3H]gougerotin than do mock-infected cells, at a time p.i. at which either compound is more inhibitory to protein synthesis in infected, than in mock-infected cells. The concentrations of hygromycin and gougerotin required to inhibit protein synthesis in intact cells (irrespective of whether they are infected or not) are several orders of magnitude higher than those required in either permeabilized cells or in cell-free systems. Infected cells take up 86Rb+ at the same rate as mock-infected cells, their intracellular content of K+ is the same, and the activity of the Na+ pump is the same. It is concluded that the increased efficacy of hygromycin and gougerotin in virus-infected cells is a consequence of altered intracellular compartmentation and that increases in permeability of the plasma membrane, if any, are so small as to be undetectable by direct methods.     

MR pelvimetry--a practical alternative.

Pelvimetry remains a useful technique as part of the assessment of the term breech pregnancy where vaginal delivery is planned. MR pelvimetry is accurate, well tolerated and shows soft-tissue structures as well as bone. It avoids the potentially carcinogenic effects of ionising radiation and is thought to be completely safe for mother and fetus. A technique of MR pelvimetry is described which uses gradient-echo sequences. This quick, practical method makes minimal inroads into valuable scanning time, and may therefore be considered a potentially cost-effective alternative to conventional pelvimetry.     

Gastric and duodenal obstruction in patients with cholangiocarcinoma in the porta hepatis: increased prevalence after radiation therapy.

OBJECTIVE. Our objective was to study the imaging findings in patients who had gastric and duodenal obstruction as a long-term complication of cholangiocarcinoma and to determine if the obstruction was associated with radiation therapy. MATERIALS AND METHODS. Between 1973 and 1989, 96 patients had either curative resection or palliative stenting for cholangiocarcinoma involving the hepatic duct bifurcation. Sixty-three (66%) also received adjuvant radiation therapy ranging from 4960 to 7220 rad (cGy). Gastric outlet or duodenal obstruction or both developed subsequently in seven of the 63 patients treated with radiation therapy. Radiographic studies, including upper gastrointestinal series and CT, and medical and surgical records for these seven patients were retrospectively reviewed. RESULTS. Upper gastrointestinal series in the seven patients with obstruction showed narrowing of the lumen, deformity and enlargement of gastric and duodenal mucosal folds, and delayed gastric emptying. CT performed in five of the seven patients showed thickening of the wall of the gastric antrum and small bowel and retained food and fluid within the stomach. All seven patients required gastrojejunostomy; at surgery, dense adhesions and fibrosis were found, and it was not evident whether the obstruction was due to the tumor or to radiation fibrosis. However, because this complication was seen only after radiotherapy, it was presumed to be radiation fibrosis. CONCLUSION. Our experience suggests that radiation therapy increases the risk of postoperative gastric and duodenal obstruction in patients undergoing surgery for cholangiocarcinoma.