Development of voltage-dependent ionic currents in rat cerebellar granule cells grown in primary culture

In this work we studied the excitable properties of cerebellar granule cells grown in primary culture in the presence of "high" KCl (25 mM). Whole cell patch-clamp records of currents were obtained from cells at 1-33 days in culture (DIC). Sodium currents, blocked by TTX, were present from the first DIC and did show slow developmental changes. Two types of potassium currents were detected at all DIC: a delayed rectifier current (IK) and an inactivating current (IA). Both IK and IA increased until 7 to 9 DIC (four and two times respectively). Most of the IA increase, however, correlated with an increase in cell size, monitored by measurements of cell membrane capacitance (Cm) and the current density thus did not change. Conversely, delayed rectifier potassium current density did increase in the initial DIC (3-6) and did not change significantly after this time. Calcium currents were not detectable at any DIC under our experimental conditions.     

Laparoscopic cholecystectomy: incidents and complications. Analysis of 8002 consecutive cholecystectomies performed at the Surgical Clinic III Cluj-Napoca

Incidents and postoperative complications of laparoscopic cholecystectomy (LC) are analyzed based on a series of 8002 patients who underwent the procedure during a period of seven years. Conversion rate was 2.02% (161 cases) and 6 (0.07%) death were encountered. Intraoperative hemorrhage (2.43%) could be controlled by intraoperative haemostasis in all but 8 patients (bleeding from the hepatic bed and from the cystic artery) which required conversion. Lesions of the bile ducts occurred in 16 patients (0.2%), 13 of them being identified during the operation and solved by conversion or laparoscopic choledochorraphy (for a tangential lesion). Postoperative complications required re-intervention in 45 patients: 11 for bile leak, 19 for choleperitoneum, 6 for hemorrhage, 4 for subhepatic abscesses and 5 for remnant CBD lithiasis. There was 1 puncture of the Douglas pouch in a case of choleperitoneum, 7 laparoscopic re-interventions and 25 open surgery re-interventions. EST solved postoperative bile leaks (from the gallbladder bed) successfully in 7 cases and remnant CBD lithiasis (5 cases). So, 44% of the cases were treated by minimally invasive means (laparoscopic re-interventions or endoscopic procedures). The majority of the incidents and postoperative complications were linked to the presence of an acute cholecystitis and were partially due to some technical limits of the laparoscopic technique of the gallbladder bed peritonisation. The minimally invasive treatment of postoperative complications, was very efficient and offered optimum healing conditions.     

Chronic low dose exposure of hospital workers to ionizing radiation leads to increased micronuclei frequency and reduced antioxidants in their peripheral blood lymphocytes

Abstract

Purpose: The regular low dose occupational exposure to ionizing radiation may induce deleterious health effects, which may be of particular interest to medical radiation workers who daily handle X-ray machines. Human peripheral blood lymphocytes are able to retain the signature of radiation-induced DNA damage, therefore, the present study was undertaken to investigate the DNA damage and antioxidants status in hospital workers occupationally exposed to low doses of X-rays.

Materials and methods: The peripheral blood lymphocytes of the occupationally exposed and control groups matched for age, gender, tobacco usage, and alcohol consumption were cultured and micronuclei frequency was determined. Activities of antioxidant enzymes and lipid peroxidation were also estimated in their plasma.

Results: The micronuclei frequency in the occupationally exposed group (n?=?33), increased significantly (p?<?.0001) followed by reduced glutathione-s-transferase (p?<?.01) and catalase (p?<?.001) activities, and increased lipid peroxidation (p?<?.05) when compared to the control group (n?=?33). Occupational exposure resulted in an effective dose ranging between 3.14 to 144.5 mSv (40.88?±?39.86mSv) depending on the employment duration of 3–29 years (10.33?±?7.05 years). A correlation between the micronuclei frequency (p?<?.05) and catalase activity (p?<?.05) existed in the occupationally exposed individuals depending on the smoking habit, age, duration of employment, cumulative exposure dose and number of patients handled per day.

Conclusions: We have observed that protracted low dose exposure to ionizing radiation is an inevitable occupational hazard leading to persistence of oxidative stress and increased genomic instability in the radiological technicians depending on the time spent with X-rays, cumulative dose received and the number of patients handled daily raising the risk of cancer development.     

Procedures for preventing postoperative nausea and vomiting after laparoscopic cholecystectomy: dexamethasone and ondansetron

This randomized double-blind study was undertaken to evaluate the efficacy of ondasetron and dexamathesone in reducing the incidence of postoperative nausea and vomiting after laparoscopic cholecystectomy. The study covered 60 patients (ASA I/II) who had undergone laparoscopic cholecystectomy under general anesthesia. The patients were divided into two groups: 1) 30 patients who received dexamethasone, 4 mg i.v.; and 2) 30 patients who took ondansetron, 4 mg i.v., prior to general anesthesia. Postoperatively, nausea, vomiting, and severe pain (VAS) were observed every 6 hours within the first 24 hours. Postoperative nausea and vomiting occurred in 6 (20) patients in Group I and in 13 (43.33) patients in Group 2 (p < 0.05), while vomiting did only in 5 (16.66%) patients in Group I and 4 (13.33%) in Group 2 (p > 0.05). The least intensity of postoperative pain was observed in Group 1, but the difference between the study groups was insignificant. It is concluded that dexamethasone is more effective in preventing postoperative nausea and vomiting after laparoscopic cholecystectomy than ondansetron. This is mainly determined by a significant reduction in the incidence of postoperative nausea.     

Effect of bismuth subgallate (a hemostatic agent) on bone repair; a histologic,radiographic and histomorphometric study in rats

Bismuth subgallate (BS) is a hemostatic agent used for soft tissue surgery in otorhinolaryngology and dermatology. Its effect on bone repair has not been studied. The present study undertook a quantitative and qualitative evaluation of post-extraction bone healing in the presence of BS. Under intraperitoneal anesthesia, forty male Wistar rats, 80 ± 5 g body weight, underwent the extraction of both lower first molars. BS was placed in the right post-extraction socket (group E) and the contralateral socket served as control (group C). The animals were killed in groups immediately, 7, 14 and 30 days post-extraction. The mandibles were resected, radiographed and processed for embedding in paraffin. The mesial socket was sectioned along the bucco-lingual axis and stained with hematoxylin-eosin. Total tissue volume and trabecular bone volume of the apical third of the sockets were determined histomorphometrically. At 14 and 30 days post-extraction, group E exhibited bone tissue that resembled that of group C. Histomorphometric analyses showed no statistically significant differences between groups C and E. Bismuth subgallate did not interfere with post-extraction bone healing. Further studies will analyze the effect of this hemostatic agent on bone repair in aniticoagulated rats.     

Pharmacological profile of apigenin, a flavonoid isolated from Matricaria chamomilla

Dried flowers of Matricaria chamomilla L. are largely used to provide sedative as well as spasmolytic effects. In the present study, we examined in particular the pharmacological property of a fraction isolated from a methanolic extract of M. chamomilla, which was identified by HPLC-MS-MS analysis as apigenin. By radioreceptor binding assays, we demonstrated the ability of the flavone to displace a specific radioligand, [(3)H]Ro 15-1788, from the central benzodiazepine binding site. Electrophysiological studies performed on cultured cerebellar granule cells showed that apigenin reduced GABA (gamma-aminobutyric acid)-activated Cl(-) currents in a dose-dependent fashion. The effect was blocked by co-application of Ro 15-1788, a specific benzodiazepine receptor antagonist. Accordingly, apigenin reduced the latency in the onset of picrotoxin-induced convulsions. Moreover, apigenin injected i.p. in rats reduced locomotor activity, but did not demonstrate anxiolytic, myorelaxant, or anticonvulsant activities. The present results seem to suggest that the inhibitory activity of apigenin on locomotor behaviour in rats cannot be ascribed to an interaction with GABA(A)-benzodiazepine receptor but to other neurotransmission systems, since it is not blocked by Ro 15-1788.     

2-Aryl-3-indoleacetamides (FGIN-1): a new class of potent and specific ligands for the mitochondrial DBI receptor (MDR).

The 2 aryl-3-indoleacetamides (FGIN-1) are a new class of compounds that potently (nM) and selectively bind to glial mitochondrial diazepam binding inhibitor (DBI) receptors (MDR), previously called peripheral benzodiazepine receptors, and increase mitochondrial steroidogenesis. The high-affinity binding of FGIN-1 to MDR derivatives depends on the following chemical characteristics: 1) the dialkylation of the amide; 2) the chain length of this alkyl substitution; and 3) the halogenation of aryl groups appended to the indole nucleus. FGIN-1 derivatives do not bind to gamma-aminobutyric acid (GABAA), GABAB, glycine, glutamate, dopamine, serotonin, opiate, cholecystokinin, beta adrenergic, cannabinoid or sigma receptors. FGIN-1-27 [N, N-di-n-hexyl 2-(4-fluorophenyl)indole-3-acetamide] enters the brain, and for this reason, this FGIN-1 compound is potent and efficacious behaviorally. Like the neurosteroid 3 alpha-5 alpha tetrahydrodeoxycorticosterone (THDOC), FGIN-1-27 delays the onset of isoniazid-induced convulsions, but fails to delay the onset of bicuculline-induced convulsions. However, differently from THDOC, the FGIN-1-27 anticonvulsant action is blocked by the isoquinoline carboxamide PK 11195. In the elevated plus maze test, FGIN-1-27 inhibits neophobia manner that is antagonized by PK 11195 but not by flumazenil. Because FGIN-1-27 binds to MDR and does not bind to the GABAA receptors, it is inferred that FGIN-1-27 may act on GABAA receptors indirectly, presumably via a stimulation of neurosteroid synthesis and release from glial cells.