Studies on the relationship between transaldolase activity and testosterone synthesis in Leydig cells of pubertalmice

Objective: To study the relationship between transaldolase activity, protein expression and testosterone synthesis in Leydig cells of pubertal mice. Methods: Leydig cells were cultured for 2 hours and 8 hours, to the Stimulation Group, hCG was added and to the Controls, only the vehicle. The testosterone concentration was then determined by enzyme-linked immunoadsordent assay (ELISA) and the transaldolase activity and protein expression by Western blot. Results: (1) Both the testosterone concentration and the transaldolase activity in both Stimulation Groups were significantly higher than those in the corresponding Controls (2 h: p<0.05-0.01; 8 h: P<0.001); (2) The ratios of the A isoform, the B isoform and the total transaldolase protein to β-actin between the Stimulation and Control Groups did not differ signifi-cantly. Conclusion: hCG stimulates the transaldolase activity as well as the testosterone synthesis in the Leydig cells of pubertal mice, indicating a positive relationship between them.     

ACETALDEHYDE METABOLISM: DIFFERENCES BETWEEN UChA AND UChB RATS

In order to explore the influence of acetaldehyde (AcH) metabolismon the voluntary ethanol intake of genetically low (UChA) andhigh (UChB) ethanol consumer rats, the AcH disappearance rate(ADR) after incubation with homogenates and subcellular fractionsfrom liver and brain was determined. In addition, the effectof disulfiram pretreatment on AcH metabolism was studied. Maleadult rats of both strains were used. ADR was assayed in totalhomogenates, and in mitochondrial as well as 9000 g supernatantfractions of liver and brain. AcH was measured by gas chromatography.In some experiments, rats were pretreated with disulfiram (300mg/kg po) 24 hr before the studies. The result showed no straindifference in ADR in homogenates or subcellular fractions ofliver from untreated rats, but for disulfiram pretreated ratsa significantly lower decrease of ADR in samples from UChB comparedto UChA rats was observed. This result is consistent with alower peak AcH level in UChB compared to UChA rats after a loadof ethanol (60 mmole/kg ip). Concerning brain homogenates, ahigher ADR was observed in homogenates and crude mitochondrialfractions of UChB than of UChA rats. This difference was notobserved when the incubation was performed without adding NADor in the absence of oxygen. These results provide evidenceof strain differences in mitochondrial AcH metabolism, the natureand origin of which deserve further study.     

Scintigraphic visualization of intrathecal liposome biodistribution

Background: Liposomes containing local anaesthetics have been administered intrathecally and in the epidural space. Poor attention has been given to the pharmacokinetics of liposomes as drug carriers. Therefore, we observed the biodistribution of liposomes after intrathecal injection in rats by scintigraphic imaging during 24 h.
Methods: We administered ⁹⁹Tc-labeled multilamellar (MLV) and small unilamellar vesicles (SUV) of defined size and volume dispersities into the cerebrospinal fluid at the lumbar level. Those vesicles were free of contamination by radiolabeled colloids as visualized by light and electron microscopy and of neurotoxic products from phosphatidylcholine hydrolysis and peroxidation, both during the preparation process and after 24 h incubation in cerebrospinal fluid at 37°C in vitro.
Results: SUV immediately diffused from the lumbar site of injection to the head and were cleared between 1 and 24 h after injection. MLV were cleared more slowly from the spinal space and appeared in the head region 1 h after injection where they accumulated up to 24 h. These differences were explained in terms of vesicle sizes and volumes. SUV with 0.05 μm diameters were rapidly absorbed into the blood through the arachnoid granulations. In contrast, particles larger than the upper size limit of the arachnoid granulations permeability (±8 μm) could accumulate in the head with a slow elimination rate.
Conclusion: This difference in clearance from the intrathecal space outlines the importance of defining the size of the liposomes, the distribution of a tracer or a drug inside the liposomal preparation, the chemical stability and the absence of toxic degradation products of liposome formulations before clinical use.     

Free vascularized jejunum interposition for pharyngoesophageal reconstruction after total laryngopharyngectomy

The records of 28 patients who underwent free jejunal graft reconstruction after resection for cancer involving the pharynx were analysed. Seven patients had a T₃ carcinoma, 15 patients T₄ and six patients recurrence after laryngectomy. Ten patients had received radiotherapy in the past. Post-operatively, 15 patients (54%) had complications and two patients (7%) died. No significant difference was observed in the complication rate between the group that received radiotherapy in the past and those who did not. Nineteen patients received post-operative radiotherapy. Nine patients had no radiotherapy on the basis of complete resection or because of serious complications. For the whole group the 2-year recurrence free period and survival were 42% and 51% respectively. The postoperative radiotherapy group had a significantly better survival (73%) and recurrence free period (63%) than the group without post-operative radiotherapy (0%). Thus, post-operative radiotherapy seems indicated irrespective of resection margins.     

ETHANOL DECREASES BASAL CYTOSOLIC-FREE CALCIUM CONCENTRATION IN CULTURED SKELETAL MUSCLE CELLS

We analysed the effect of ethanol on basal cytosolic-free calciumconcentration ([Ca²⁺]₁) in cultured rat myocytes. Ethanol causeda dose-dependent decrease of the resting [Ca²⁺]₁). Removal ofethanol was followed by a transitory increase of [Ca²⁺]₁ abovethe basal level. In cells chronically exposed to ethanol, [Ca²⁺]₁normalized to the previous level.     

Mechanisms and patient compliance of dust-mite avoidance regimens in dwellings of mite-allergic rhinitic patients

We report on the mechanisms, the environmental changes and patient compliance with regard to conventional and new dust and mite avoidance measures to prevent allergic symptoms caused by mite allergens, taking into account both allergen contamination and the developmental success of pyroglyphid Acari. Twenty patients with persisting rhinitic complaints were selected and matched. Although the patients had performed some conventional dust and mite avoidance measures (patient compliance was 90%), the dwellings proved to be a stimulus for mite development. Moisture problems due to faulty construction and excessive moisture production were common. Since humidity conditions could not be changed at short notice, the 20 homes were subjected to the new variants of mite allergen avoidance based on intensive cleaning without (control) and with an acaricide incorporated (acaricidal cleaner [Acarosan]). After the carrying out of conventional avoidance measures, these patients still had allergic symptoms, and dust from only 23 to 52% of their textile objects was under the proposed guanine (mite faeces indicator) risk level. Only the acaricidal cleaner was able to decrease the allergenic mite load (and the burden of the patients) significantly in this 12 month period. With respect to mite-extermination, acaricidal cleaning was 88% better than intensive cleaning. Reduction of guanine was 38% better in the Acarosan treatment group. Clinical results have been reported elsewhere. A significant difference in favour of the acaricidal cleaning was seen in both subjective (as regards symptoms) and in objective data (total IgE). Another 50 patients were questioned. About 90% were willing to spend two weekends (70%), or at the most one weekend (20%) per year sanitizing the dwelling by cleaning it with the whole family. The authors of this report consider acaricidal cleaning to be a significant improvement in the management of mite-allergic diseases, such as rhinitis. Compared with the replacement of home textiles, this treatment is less expensive and more effective. Patient compliance is acceptable, but depends on acceptance by physicians and the initial motivation and consequent burden on the patient.     

Cardiac tamponade after intrapericardial diaphragmatic hernia

An unusual case of intrapericardial diaphragmatic hernia ispresented. Cardiac tamponade occurred in the operating roomsoon after induction of anaesthesia. Surgical removal of theherniated omentum and stomach allowed haemodynamic improvement.The pathophysiology is discussed and patients with cardiac tamponadereviewed.