A study examining intravenous ethanol-conditioned place preference in C57BL/6J mice

The reinforcing effects of intravenous (I.V.) ethanol were examined in C57BL/6J (C57) mice with a conditioned-place-preference (CPP) paradigm. Before CPP testing, adult mice underwent jugular catheterization. On the following day, subjects were acclimated to a two-compartment CPP chamber. A 15-min nondrug pretest was conducted to determine compartment preference. For the treatment group, I.V. ethanol [30% (v/v), 3.4 microl/min, 25 min] was paired with the nonpreferred compartment, whereas I.V. saline was paired with the preferred compartment. The control group received I.V. saline in both compartments. Two conditioning sessions were conducted per day (0900 and 1500), and the order of the infusions was counterbalanced across subjects. The drug-free posttest was identical to the pretest, except that it occurred on the day after the final drug/compartment pairing. The entire procedure required 6 days. After just two pairings with ethanol, with a cumulative ethanol dose of only 0.82 g/kg/day, significant CPP was noted in the treatment group, whereas no change in compartment preference was noted for the control group. A separate group of C57 mice were trained to discriminate intraperitoneal ethanol (1.5 g/kg) from saline using a two-lever drug discrimination paradigm. After training was complete, these mice also underwent jugular catheterization. Substitution testing was conducted with I.V. ethanol [30% (v/v), 6.4 microl/min, 12 min] and saline. The results indicate that the subjective effects of ethanol did not differ according to the route of administration. Together, these experiments provide evidence that ethanol is rewarding for C57 mice, as indexed by ethanol CPP, and that the subjective effects of intravenously and intraperitoneally administered ethanol are similar.     

Estimation of genetic parameters for growth, feed consumption, and conformation traits for double-muscled Belgian blue bulls performance-tested in Belgium

For 1,442 Belgian Blue bulls performance-tested at the Centre de Sélection de la Race Blanc-Bleue Belge, nine traits were observed: height at withers at 7 mo, height at withers at 13 mo, weight at 7 mo, weight at 13 mo, average feed consumption of concentrates, average daily gain, average feed consumption of concentrates per average daily gain, average feed consumption of concentrates per mean metabolic weight, and price per kilogram of live weight. This price is based on muscle conformation and is therefore used as muscle conformation score. Restricted maximum likelihood with a derivative-free algorithm was used to estimate (co)variance components because there were different models and missing values per trait. Estimates of heritabilities were above .50 except for average feed consumption per average daily gain (.16) and average feed consumption per mean metabolic weight (.33). Estimates of genetic and phenotypic correlations between height at withers and weight traits were positive and moderate to high. Average daily gain showed a negative genetic correlation with weight at 7 mo (-.68) but had positive correlations with height at withers at 13 mo and weight at 13 mo (.22 and .43). Muscle conformation expressed as price per kilogram of live weight was related to low average feed consumption per average daily gain. Average feed consumption showed high correlations with weight at 7 mo and weight at 13 mo. Average feed consumption per average daily gain had a high negative genetic correlation with average daily gain (-.89).     

Pharmacologic atrial natriuretic peptide reduces human leg capillary filtration

Atrial natriuretic peptide (ANP) is produced and secreted by atrial cells. We measured calf capillary filtration rate with prolonged venous-occlusion plethysmography of supine healthy male subjects during pharmacologic infusion of ANP (48 pmol/kg/min for 15 min; n = 6) and during placebo infusion (n = 7). Results during infusions were compared to prior control measurements. ANP infusion increased plasma [ANP] from 30 +/- 4 to 2,568 +/- 595 pmol/l. Systemic hemoconcentration occurred during ANP infusion: mean hematocrit and plasma colloid osmotic pressure increased 4.6 and 11.3%, respectively, relative to preinfusion baseline values (p < 0.05). Mean calf filtration, however, was significantly reduced from 0.15 to 0.08 ml/100 ml/min with ANP. Heart rate increased 20% with ANP infusion, whereas blood pressure was unchanged. Calf conductance (blood flow/arterial pressure) and venous compliance were unaffected by ANP infusion. Placebo infusion had no effect relative to prior baseline control measurements. Although ANP induced systemic capillary filtration, in the calf, filtration was reduced with ANP. Therefore, pharmacologic ANP infusion enhances capillary filtration from the systemic circulation, perhaps at upper body or splanchnic sites or both, while having the opposite effect in the leg.     

Resolution of a left ureteral stone using electrohydraulic lithotripsy in a thoroughbred colt

A 3-year-old Thoroughbred colt was presented for evaluation of azotemia and anorexia. Physical examination revealed a ureterolith in the left ureter, approximately 10 cm from the bladder, which was thought to obstruct urine flow by approximately 90% when viewed cystoscopically. Ultrasonographic examination of both kidneys revealed indistinct corticomedullary junctions, and the right kidney was more hyperechoic. A percutaneous biopsy of the right kidney revealed chronic interstitial nephritis with marked interstitial medullary fibrosis. Medical therapy consisting of IV fluids, sodium chloride PO, and ammonium chloride PO was initiated. Ureteroscopic electrohydraulic lithotripsy via a perineal urethrostomy was used to successfully remove the stone. Klebsiella oxytoca, which responded to oral enrofloxacin therapy, was cultured from the urine after surgery. Azotemia resolved and the horse resumed training.     

Postmortem analysis of bone growth into porous-coated acetabular components

Microradiography, backscattered electron microscopy, and histological analysis were used to conduct a quantitative postmortem study of seven consecutively retrieved anatomical porous replacement acetabular components that had been inserted during total hip arthroplasties. Screws had been used for the initial fixation of six components. The microradiographic analysis of all seven components showed that an average (and standard deviation) of 84 +/- 9 per cent (range, 72 to 93 per cent) of the porous coating was in direct apposition to the periprosthetic bone. The backscattered electron images demonstrated that an average of 12 +/- 6 per cent (range, 4 to 21 per cent) of the space available in the porous coating was occupied by ingrown bone. The amount of bone ingrowth was not significantly different among the three zones delineated by DeLee and Charnley. Uniformity of bone growth into the porous coating suggests that the preferential loading that occurs in the superior region did not differentially affect the bone ingrowth. The present study showed that consistent bone growth into anatomical porous replacement acetabular components can be achieved.     

Trends in rates of occupational fatal injuries in the United States (1983-92)

Recent advancements in laparoscopic surgery have made laparoscopic splenectomy possible. We retrospectively compared the outcomes of laparoscopic versus open splenectomy in patients with idiopathic thrombocytopenic purpura (ITP) or beta-thalassemia. From July 1993 to July 1997, 52 patients (ITP, 43 cases; beta-thalassemia, 9 cases) underwent either laparoscopic (30 patients, 9 men, 21 women; average age, 36.9 years) or conventional open splenectomy (22 patients, 5 men, 17 women; average age, 34.3 years). The two groups were similar in terms of sex, age, diagnosis, duration of disease, preoperative platelet count, and spleen size. The mean surgical time, estimated amount of blood loss, duration of postoperative recovery, analgesic usage, and complications were compared between the two groups. Laparoscopic splenectomy was successful in 29 (97%) of the 30 patients. The mean surgical time in the laparoscopy group was longer than in the open splenectomy group (190.6 vs 113.9 minutes, p < 0.01). The laparoscopy group had earlier postoperative oral intake (15.2 vs 52.6 hours, p < 0.01), less usage of analgesics (meperidine 50 mg/unit, 1.1 vs 2.8 units, p < 0.01) and a shorter postoperative hospital stay (4.1 vs 6.8 days, p < 0.01). The estimated blood loss, incidence of accessory spleen, surgical complication rate, and recurrence rate of thrombocytopenia were similar in the two groups. Our findings show that laparoscopic splenectomy in patients with ITP or beta-thalassemia is as safe as the open approach. While laparoscopy required a longer surgical time, the recovery period was shorter, analgesic use was less, and physical discomfort was less severe.     

Ischemia of the anterior vestibular artery (Lindsay-Hemenway syndrome). Review and comments

INTRODUCTION: The Lindsay and Hemenway syndrome is produced by ischemia in the territory of the anterior vestibular artery and is characterized by an initial episode of acute vertigo followed by benign paroxysmal positional vertigo and decreased or abolished caloric response. OBJECTIVE: To determine the incidence of anterior vestibular artery syndrome in patients with benign paroxysmal positional vertigo. DESIGN: A 3-year retrospective study (January 1994 to December 1996). SETTING: Patients with benign paroxysmal positional vertigo of the Zamora and Salamanca (Spain) health districts seen in two outpatients clinics. STUDY SUBJECTS: Ninety-eight patients with benign paroxysmal positional vertigo. RESULTS: Sixteen patients diagnosed as anterior vestibular artery syndrome were revised (16.3%). CONCLUSIONS: Although the literature is scarce, the incidence of Lindsay-Hemenway syndrome seems to be underestimated.     

Malignant meningioma in Gorlin's syndrome: cytogenetic and p53 gene analysis. Case report

Gorlin's syndrome, also known as multiple basal cell carcinoma syndrome, is a familial tumor condition with autosomal-dominant inheritance. Patients develop multiple basal cell carcinomas beginning in childhood. They also have a typical dysmorphic facies, skeletal malformations, and a particular type of epithelial cyst of the jaws. Recent evidence localizes a Gorlin's syndrome locus on chromosome 9 at band q31. Both tumors and malformations of the central nervous system occur with Gorlin's syndrome. Medulloblastoma is the primary brain tumor most frequently associated with this syndrome; over 40 such cases have been reported. However, only seven cases of meningioma associated with Gorlin's syndrome have been described. The authors report the case of a woman with Gorlin's syndrome whose mother and maternal grandfather also had the condition. The patient was found to have a medulloblastoma at 4 years of age and presented with a large bifrontal meningioma at 19 years of age. The meningioma was histologically malignant and had a complex karyotype with multiple translocations including a t(5;9) with the breakpoint on chromosome 9 located at 9q32. The constitutional karyotype of the mother was normal. No mutations of exons 5 to 9 of the p53 gene were detected using single-stranded conformational polymorphism analysis.     

Iodide suppression of major histocompatibility class I gene expression in thyroid cells involves enhancer A and the transcription factor NF-kappa B

A sexual dimorphism more marked than in living humans has been claimed for European Middle Pleistocene humans, Neandertals and prehistoric modern humans. In this paper, body size and cranial capacity variation are studied in the Sima de los Huesos Middle Pleistocene sample. This is the largest sample of non-modern humans found to date from one single site, and with all skeletal elements represented. Since the techniques available to estimate the degree of sexual dimorphism in small palaeontological samples are all unsatisfactory, we have used the bootstraping method to asses the magnitude of the variation in the Sima de los Huesos sample compared to modern human intrapopulational variation. We analyze size variation without attempting to sex the specimens a priori. Anatomical regions investigated are scapular glenoid fossa; acetabulum; humeral proximal and distal epiphyses; ulnar proximal epiphysis; radial neck; proximal femur; humeral, femoral, ulnar and tibial shaft; lumbosacral joint; patella; calcaneum; and talar trochlea. In the Sima de los Huesos sample only the humeral midshaft perimeter shows an unusual high variation (only when it is expressed by the maximum ratio, not by the coefficient of variation). In spite of that the cranial capacity range at Sima de los Huesos almost spans the rest of the European and African Middle Pleistocene range. The maximum ratio is in the central part of the distribution of modern human samples. Thus, the hypothesis of a greater sexual dimorphism in Middle Pleistocene populations than in modern populations is not supported by either cranial or postcranial evidence from Sima de los Huesos.