Dexmedetomidine induces conditioned place preference in rats: Involvement of opioid receptors.

Dexmedetomidine (DEX) is an alpha-2 adrenergic agonist drug recently introduced to anesthesia practice. Certain agents used in anesthesia practice have been associated with abuse and addiction problems; however, few studies have investigated the role of DEX on addictive processes. Here, the effects and possible mechanisms of action of DEX on conditioned place preference (CPP), a model used for measuring the rewarding effects of drug abuse in rats, was investigated. The CPP apparatus was considered "biased" as the animals preferred the grid side to the mesh side. Male Wistar albino rats weighing 250-300 g were divided into several groups, including control (saline), morphine (10mg/kg), DEX (2.5-20 µg/kg), naloxone alone (0.5mg/kg) and a combination (0.5mg/kg naloxone plus 20 µg/kg DEX) (n=7-8 for each group). The CPP effects of morphine, DEX, saline and the combination were evaluated. All the drug and saline administrations except naloxone were performed by intraperitoneal (ip) injections. Naloxone was injected subcutaneously (sc) when given alone or in combination with DEX. Morphine (10mg/kg) and DEX (5-20 µg/kg) produced CPP that were statistically significant relative to saline-injected rats. DEX-induced CPP was significantly reversed by pretreatment with naloxone, an opioid antagonist. Naloxone alone treatment did not cause any significant effect on CPP. Our results suggest that DEX produces CPP effects similar to morphine in rats and that opioidergic mechanism may be responsible for DEX-induced CPP. Thus, DEX might have the potential to be addictive, and this possibility should be considered during clinical application of this drug.

Reduction of surgery-induced peritoneal adhesions by continuous release of streptokinase from a drug delivery system.

Postoperative abdominal adhesions may lead to intestinal obstruction and infertility. The effect of continuous release of streptokinase to the peritoneal cavity on postoperative adhesions was examined under experimental conditions. Peritoneal adhesions were induced in rats and the animals were further treated by intraperitoneal administration of streptokinase solution, polyhydroxybutyrate-co-hydroxyvalerate (PHBV) membrane alone and streptokinase loaded PHBV membrane and compared to sham operated and untreated groups. Formation of adhesions was evaluated by quantitative macroscopic grading, histopathologically with light microscopy, on the following week. Streptokinase loaded PHBV prevented postoperative adhesion formation in 90% of the cases. PHBV membrane alone also reduced the severity of adhesions due to its anti-adhesive properties. Histopathological examination revealed limited foreign body reaction due to PHBV. Continuous streptokinase activity in the peritoneal cavity during early post-surgical period prevents postoperative adhesion.

Correlation between clinical stages and EEG findings of subacute sclerosing panencephalitis.

In this retrospective study 67 patients with SSPE seen between the years 1980 and 1998 were reviewed. Using the criteria of SSPE diagnosis (clinical signs, characteristic EEG patterns, high titres of measles antibodies in the serum and CSF), the patients were divided into two groups. Group A fulfilled all criteria, however, due to the inability of measuring measles antibody before 1987, it was not possible to observe the third criterion in Group B. Among 67 patients, groups A and B consisted of 51 boys and 16 girls ranging in age between 1 to 23 years, mean age 13.1. The male/female ratio was 3.1. The periodic EEG complexes (PCs) were usually bilateral, synchronous and symmetrical. PC amplitude asymmetry was seen in 12 patients and 2 patients had no PC synchronization between the hemispheres. Six patients had more than one form of PC. Delta activity in anterior hemispheres after PC was seen in 40 patients, mostly in stage 2A. Thirty-two patients had focal epileptiform abnormalities in multiple locations at every stage but most frequently in frontal, central and temporal regions. One patient had PC over both hemispheres and periodic lateralized epileptiform discharges (PLEDs) over the right hemisphere. The EEG findings described and observed in our study do not seem to be specific to SSPE but these findings were not atypical or unusual.

Antimicrobial Effects of Propolis Extracts on Escherichia coli and Staphylococcus aureus Strains Resistant to Various Antibiotics and Some Microorganisms.

ABSTRACT Propolis is collected by worker honey bees from the trees. The bees pack propolis on their hind legs, carry it to their colony, and use it as a sterilant in the hive. Propolis has also been used by humans since early times for various purposes and, especially, as a medicine because of its antimicrobial properties. In this study, antimicrobial effects of propolis samples on three Escherichia coli and two Staphylococcus aureus strains that are multiresistant to antibiotics and on Salmonella typhimurium, Bruceila abortus, Proteus mirabilis, Streptococcus pyogenes, Bacillus cereus, Candida tropicalis, and Aspergillus niger were studied. Propolis extracts were prepared with acetone and dimethyl sulfoxide (DMSO). At concentrations of 10 and 25 ml, propolis extracts affected all of the microorganisms in acetone and DMSO in concentrations of 10.0, 50.0, and 100.0 ppm. The results detected in this in vitro study provided evidence that propolis may be used as an antimicrobial agent against many microorganisms.

Neonatal hypertrophic pyloric stenosis: congenital or infantile?

Hypertrophic pyloric stenosis (HPS) is very rare during the newborn period. Here we present a fullterm male neonate with abundant hematemesis 12 hours after birth which interrupted oral feeding. Bleeding subsided within three days after conservative measures, and oral feeding was restarted but not tolerated. The vomiting was effortless and nonbilious. An upper gastrointestinal series revealed gastric dilatation and partial obstruction of the gastric outlet. HPS was found by laparotomy on the fourth day and Fredet-Ramstedt pyloromyotomy relieved the gastric emptying. This is one of the few cases of HPS present at birth, which was diagnosed and surgically treated early, and we suggest a congenital etiology in previously reported cases of HPS. Hypertrophic pyloric stenosis (HPS) is a common cause of pediatric surgery. Usually young infants are involved; HPS is extremely rare in neonates and infants older than 6 months. Vomiting typically begins between the 3rd and 6th week of life, although some infants may have mild symptoms like regurgitation from birth.

MRI in subacute sclerosing panencephalitis.

Subacute sclerosing panencephalitis (SSPE) is a progressive, slow virus infection of the brain, caused by the measles virus, attacking children and young adults. We investigated 15 patients with SSPE by MRI, with 5 normal and 10 pathological results. In the early period, lesions were in the grey matter and subcortical white matter. They were asymmetrical and had a predilection for the posterior parts of the hemispheres. Later, high-signal changes in deep white matter and severe cerebral atrophy were observed. Parenchymal lesions significantly correlated with the duration of disease. A significant relationship between MRI findings and clinical stage was observed in the 1st year of the disease.

Distal penile hypospadias repair in children, with complete mobilization of pendulous urethra and triangular glandular flap.

OBJECTIVE: To present a technique for repair of distal hypospadias. PATIENTS AND METHODS: Sixteen children (average age 6.6 years) were treated between January 1985 and January 1991. The procedure is described. RESULTS: One child developed a mild meatal stenosis and another had a small urethral fistula; both responded to treatment. Results were excellent in the remaining 14 patients. CONCLUSION: This simple operative procedure was successful in the majority of patients and there were only two minor complications.

Blood flow determination in contralateral ovary with 133 Xe in unilateral ovarian torsion (experimental study in rabbits).

Clinical and experimental studies have shown that, in unilateral testicular torsion, some structural and hormonal changes may occur in the contralateral testis. The present study was designed to determine the effect of unilateral ovarian torsion on the blood flow in the contralateral ovary using #133Xe. Basal blood flow of the bilateral ovaries was determined in 40 prepubertal, female New Zealand rabbits. Right ovaries were then torsioned 720 degrees in all groups with the exception of the control group, where only laparotomy was performed. Bilateral ovarian blood flows were measured in the first group one hour after torsion, in the second group 8 hours after torsion, in the third group 24 hours after torsion and at the same times after laparotomy in the control group. Basal and post torsional blood flow measurements were analyzed. Contralateral ovarian blood flow was reduced after unilateral torsion in all of the groups. In the control group, there were no changes in these criteria.

A bronchopleurocutaneous fistula caused by an unusual foreign body aspiration simulating acute abdomen.

A 12-year-old boy was admitted to hospital for abdominal pain, vomiting and fever. On physical examination he had râles on the lower right hemithorax without any respiratory complaints. Chest X-ray revealed a condensation in the right lower chest. Abdominal findings were secondary to lobar pneumonia. Treatment of pneumonia with antibiotics showed no improvement over 2 days. On bronchoscopy no foreign body was seen, but pus was aspirated. Two days later a mass appeared on the right hemithorax and fistulized. An organic foreign body, Hordeum murinum, with 3-5 ml of pus was observed. Chest X-ray taken at the day of fistulization showed no pneumothorax or subcutaneous emphysema. Less than 11 cases of pneumocutaneous fistulas secondary to aspiration of grasses have been reported in literature. Why an ear of Hordeum murinum can migrate only in a forward direction and why a pneumothorax had not developed is discussed.

Histologic and ultrastructural changes in the contralateral ovary in unilateral ovarian torsion: an experimental study in rabbits.

This study was planned to investigate the extent of cellular damage of the contralateral ovary in unilateral ovarian torsion and to determine possible changes histopathologically by light and ultrastructurally by electron microscopy. Unilateral ovarian torsion was performed in 21 prepubertal, female New Zealand rabbits. One, 8 and 24 hours after the torsion, contralateral ovaries were biopsied. The control group consisted of rabbits without any torsion. Contralateral cellular damage was demonstrated after unilateral torsion. Oocytic nuclei, mitochondria, lysosomes and ovarian stromal cells were also affected when evaluated ultrastructurally.

Augmentation of mucosal adaptation following small-bowel resection by electromagnetic field stimulation in rats.

Survival following massive resection of the small intestine is often possible due to substantial hyperplasia of the mucosal surface in the remaining small intestine. While nutrients provide the major stimulus for hyperplasia in the clinical setting, the availability of drugs to augment this process would have obvious therapeutic implications. Electromagnetic field stimulation (EMF) of connective tissue and skin increased the DNA and messenger RNA and protein synthesis in experimental studies. We evaluated the ability of electromagnetic field stimulation to augment mucosal hyperplasia following massive small bowel resection in the rat. Two groups of 10 Wistar rats, 250 gr body weight, were subjected to 70% jejunoileal resection. The first group received EMF stimulation for ten days at a dosage of 43.20 gauss, the second group did not receive any stimulation. After fourteen days, segmental evaluation of mucosal mass in the remaining small intestine was determined by measuring mucosal protein, and disaccharidase levels, as well as intestinal length and circumference. EMF stimulation appears to augment mucosal adaptation following massive small bowel resection in rat, in the proximal and distal small intestine.

The effect of electromagnetic field stimulation on corticosteroids-inhibited intestinal wound healing.

Electromagnetic field (EMF) stimulation has been used successfully in the clinical setting to promote healing of ununited fractures. In a few studies, EMF stimulation enhanced soft tissue healing. To investigate the effect of EMF stimulation on intestinal wound healing in normal rats and in those treated with corticosteroids, 80 Wistar rats received twice-daily injections of either saline dexamethasone (0.1 mg/kg/day for 2 weeks. Animals then underwent creation of single-layer, inverting small intestine anastomoses. All injections were continued postoperatively. Animals were grouped as intestinal anastomoses; intestinal anastomoses plus EMF stimulation; intestinal anastomoses plus dexamethasone; and intestinal anastomoses plus dexamethasone plus EMF. On postoperative days 7 and 14, the anastomosed intestines were removed and the tensile strength (TS) and hydroxyproline (OH-P) contents measured. EMF stimulation significantly increased intestinal wound healing in normal animals by the 7th and 14th day. Corticosteroids significantly impaired the healing of the small intestine anastomoses, with decreased TS and OH-P contents after the first and second weeks. However, EMF stimulation significantly reversed this inhibitory effect.

Influence of unilateral ovarian torsion to the contralateral ovary.

An experimental study was planned to show the suppression of contralateral ovary in unilateral ovarian torsions. In the study, 55 New Zealand female rabbits were used. Basal and stimulation 17 beta estradiol values were measured and unilateral torsion in 20 rabbits, bilateral torsion in ten rabbits and bilateral oophorectomy in five rabbits were performed. Eight, 16, 24 hours after the procedure, 17 beta estradiol levels were measured again and the second stimulation values maintained. The control group consisted of 20 rabbits. Values were analyzed statistically and the results were significant.

Human amniotic membrane as an intestinal patch for neomucosal growth in the rabbit model.

This experiment was carried out as a preliminary study, an attempt to grow new intestinal mucosa on human amniotic membrane in the terminal ileum in 37 rabbits. After ketamin sulfate anesthesia at laparatomy, 5-cm ileal defects were patched with human amniotic membrane (5 x 2 cm). These patched intestines were investigated on the first postoperative day and the 2nd, 5th, 10th, and 20th weeks corresponding to 4, 5, 5, 10, and 10 rabbits, respectively. Only three rabbits died in the early postoperative period. There was no evidence of intestinal obstruction or dilatation with barium meal. Microscopically, the neomucosa consisted of a thin layer of columnar epithelial cells at 2 weeks with more maturity of the villi and less irregularity and branching by 20 weeks. All patches were covered with neomucosa commencing at 2 weeks and covering the whole patch area by 20 weeks. This technique's advantages are the large size and the ease of the availability of the human amniotic membrane for neonates at risk without jeopardizing the neonates tissues. It is hoped that this method might be considered when neonatal material is scarce.

Treatment of biliary fistulas and cholelithiasis: is endoscopic sphincterotomy acceptable in the paediatric age group?

Two children, both girls, aged 11 and 16 with a postoperative biliary fistula and cholelithiasis, choledochal cyst and common bile duct stones have undergone endoscopic sphincterotomy (EST), leading to a rapid recovery from their pathologies, thanks to cooperative work. In reviewing the literature we have not come across any cases of EST in our patients' age group. There were no complications during or immediately after endoscopic sphincterotomies. We believe that it has become an important and valuable rival to conventional surgical means with correct indications and in experienced hands.

A regulatory mutation in yeast which affects catalase T formation and metabolism of carbohydrate reserves.

Mutations at the GLC1 locus in Saccharomyces cerevisiae result in a major deficiency in synthesis of catalase T, but do not affect catalase A. Three independent glc1 mutations were shown to have the same pleiotropic phenotype: catalase T deficiency, defective glycogen synthesis and defective trehalose accumulation. These three deficiencies appear to be determined by a single, nuclear gene. The possibility that glc1 mutations alter a protein kinase is considered.