Further observations on enterovirus infection in specific-pathogen-free turkey poults

To evaluate sites of enterovirus replication and to characterize the resulting lesions, twenty 4-day-old specific-pathogen-free (SPF) turkey poults were orally inoculated with an enterovirus. Twenty uninoculated SPF poults served as controls. Inoculated poults were depressed, had ruffled feathers, watery droppings, and pasted vents. Gross lesions were dilated thin-walled ceca with foamy yellow fluid. Immune electron microscopy of the gastrointestinal tract contents revealed an enterovirus with an average diameter of 23.5 nm. Immunoperoxidase and indirect immunofluorescent antibody assays revealed intracytoplasmic staining in enterocytes of the duodenum, jejunum, and ileum. This correlated with the scanning electron microscopy findings, which showed the most lesions in the jejunum and ileum. The ileum had prominent cell outlines because of rounded, distinct, bulging epithelial cells. Histopathology revealed slight shortening of villi and increased crypt depth in the intestines of inoculated poults. Our findings indicate that the small intestine is the site of turkey enterovirus replication, and the gross and microscopic changes observed are determined to result from viral damage to the enterocytes.     

Cemented versus cementless total hip arthroplasty. A comparative study of equivalent patient populations

Seventy-one cemented total hip arthroplasties (THAs) in 66 patients were compared with 70 cementless THAs in 61 patients. The cemented and cementless components were identical except for the presence of a porous proximal surface on the cementless component. The mean follow-up time was 4.3 years in the cemented group and 4.1 years in the cementless group, with a minimum follow-up of two years. Postoperative Charnley pain scores were identical for both groups, as was the incidence of limp. The final Charnley function score, however was significantly higher in the cementless group (5.6) than in the cemented group (5.1). One revision was performed in the cemented group, none in the cementless group. Complete demarcation of the bone-cement interface was presented in two cemented components and was associated with subsidence. Three cementless components had early subsidence, and two of these had complete radiopaque lines around the porous surface. None of these three patients, however, had unsatisfactory pain or function scores. The most important finding of this study is the equivalence of clinical results noted in both cemented and cementless THA as late as six years after operation.     

Incidence of acute symptomatic toxoplasma retinochoroiditis in south London according to country of birth

OBJECTIVE: To determine the incidence of acute symptomatic toxoplasma retinochoroiditis presenting to ophthalmologists for patients born in Britain and elsewhere. DESIGN: Population based, cross sectional study. SETTING: 11 districts in south Greater London. SUBJECTS: All patients presenting to NHS ophthalmologists with symptoms due to acute toxoplasma retinochoroiditis in 1992-3. MAIN OUTCOME MEASURE: Intraocular inflammation in association with a retinochoroidal scar, active adjoining retinitis, and IgG serum antibodies to toxoplasma. RESULTS: The estimated incidence of acute symptomatic retinochoroiditis for all people born in Britain was 0.4/100,000/year. If a mean of two symptomatic episodes per lifetime is assumed, 100 people born in Britain may be affected each year, about a fifth of the estimated 500-600 congenitally infected people born each year. CONCLUSIONS: A substantial proportion of people with acute symptomatic toxoplasma retinochoroiditis were born outside the country, and the number born in Britain was smaller than the number previously estimated to develop retinochoroidal lesions due to congenital toxoplasmosis. These findings suggest that prenatal screening for toxoplasmosis in Britain may be of limited benefit.     

Effect of acute ethanol ingestion on prolactin in menopausal women using estradiol replacement

The current study was to answer the question: Is enough mercury absorbed from dental amalgam fillings to produce renal damage? One hundred healthy adults (18-44 years old) filled out health questionnaires and voided urine samples. Urine mercury concentration and N-acetyl-beta-glucosaminidase (NAG) were measured. Subjects were grouped into those having amalgam fillings (N = 66) and those without (N = 34). Median (95% Confidence Interval) urine mercury was 1 (1-2) and 0 (0-0.6) ng/ml (P < 0.01) and median urine NAG was 23 (18-27) and 16 (11-18) units (P < 0.05) in the two groups respectively. People with mercury amalgam fillings excreted slightly more mercury than people without them, and have a very small increase in urinary NAG excretion that is probably of no clinical significance. This dose of mercury absorbed from amalgam appears to be too little to be a public health hazard for renal injury.     

Is laparoscopic hysterectomy a waste of time?

Laparoscopic hysterectomy (LH) is a way to avoid laparotomy. However, there is evidence that most women treated by abdominal hysterectomy are suitable for vaginal surgery. To test this hypothesis, and to determine the relative merits of laparoscopic and vaginal hysterectomy (VH) and the best technique for LH, we prospectively studied 98 women who had relative contraindications for vaginal surgery by traditional criteria. 75 underwent LH and 23 VH. The LH group included 22 women who had been assigned to this route of surgery as part of a prospective randomised controlled comparison with VH (23 women). Surgery was completed with the intended technique in 93.9% of cases. 5 women in the LH group (6.7%) and 2 in the VH group required laparotomy or additional procedures. In the prospective randomised study LH took longer than VH (mean duration 131 vs 77 min). VH was the faster procedure, irrespective of uterine size and need for oophorectomy. With LH, the operative time increased as more of the hysterectomy was carried out with laparoscopic rather than vaginal dissection. Complication rates, blood loss, analgesia requirements, and recovery were similar for the two techniques. Our study confirms that most hysterectomies could be performed vaginally, and that LH is a much slower procedure. If LH is done, it should be converted to a vaginal procedure as early as possible to reduce the overall operating time. LH does seem to be a waste of time for most patients.     

Preterm birth in rats produced by the synergistic action of a nitric oxide inhibitor (NG-nitro-L-arginine methyl ester) and an antiprogestin (onapristone)

In these experiments we have studied the in vitro metabolism of LVV-hemorphin-7 in human plasma by using reversed-phase high-performance liquid chromatography (RP-HPLC) in combination with micro-electrospray mass spectrometry (micro-ES-MS). Tandem mass spectrometry (MS-MS) was performed in order to verify the structure of the peptide fragments found. Incubations were performed with and without different protease inhibitors. Results showed that LVV-hemorphin-7 was metabolized from the N-terminal end of the peptide, probably by an amastatin-sensitive exopeptidase.     

Mechanisms of natriuretic-peptide-induced growth inhibition of vascular smooth muscle cells

OBJECTIVE: While natriuretic peptides can inhibit growth of vascular muscle cells (VSMC), controversy exists as to whether this effect is mediated via the guanylate cyclase-coupled receptors, NPR-A and NPR-B, or the clearance receptor, NPR-C. The original aim of this study was to examine the mechanism by which the NPR-C receptor regulates growth. METHODS: Rat VSMC were characterized with regard to natriuretic peptide receptor expression by RT/PCR and radioligand binding studies. The effect on growth following addition of the peptides and the ligands for NPR-C was measured by [3H]thymidine incorporation. Cyclic guanosine monophosphate (cGMP) levels were determined by radioimmunoassay and mitogen activating protein kinase activity was based on the phosphorylation of myelin basic protein. RESULTS: In rat VSMC, passages 4-12, both atrial natriuretic peptide (ANP) and C-type natriuretic peptide (CNP) dose-dependently inhibited serum and PDGF-induced VSMC growth. In contrast, NPR-C specific ligands alone had no effect on cell growth but enhanced growth inhibition when co-administered with ANP and CNP. ANP and CNP also decreased PDGF-BB-stimulated MAP kinase activity. Once again, NPR-C specific ligands alone had no effect but enhanced the effects of ANP. Furthermore, a cGMP specific phosphodiesterase inhibitor dose-dependently inhibited VSMC growth and markedly enhanced natriuretic-peptide-induced inhibition at low peptide concentrations. To examine a potential mechanism for the controversy concerning the NPR-C, we investigated the autocrine expression of ANP and CNP by VSMC and found that mRNA encoding both peptides could be detected by RT/PCR. CONCLUSION: Our findings indicate that the guanyl-cyclase-linked receptors mediate the antiproliferative actions of the natriuretic peptides on vascular smooth muscle cell growth. Moreover, we hypothesize that the apparent inhibition of growth by NPR-C specific ligands reported by others may be due to stabilization of natriuretic peptides produced by the cultured VSMC and subsequent action of these peptides at guanyl-cyclase-linked receptors.