Influence of aging on thromboxane A2 and prostacyclin levels in rat hippocampal brain slices

We have investigated the influence of age (3, 18, 24 months) on Thromboxane A₂ (TXA₂) and Prostacyclin (PGI₂) levels in hippocampal slices from F344/NHSD rats. A significant increase in TXA₂ and PGI₂ levels was observed in 18 and 24 months old compared to 3 months old animals. A significant reduction in the ratio TXA₂/PGI₂ produced by a higher increase in PGI₂ was observed in 24 month old animals. The reduction in the TXA₂/PGI₂ ratio has been related to vasodilatory and antiaggregating effects that may contribute to protect the brain against neuronal damage.     

Selective inhibitors of glial GABA uptake: synthesis, absolute stereochemistry, and pharmacology of the enantiomers of 3-hydroxy-4-amino-4,5,6,7-tetrahydro-1,2-benzisoxazole (exo-THPO) and analogues

3-Methoxy-4,5,6,7-tetrahydro-1,2-benzisoxazol-4-one (20a), or the corresponding 3-ethoxy analogue (20b), and 3-chloro-4,5,6, 7-tetrahydro-1,2-benzisothiazol-4-one (51) were synthesized by regioselective chromic acid oxidation of the respective bicyclic tetrahydrobenzenes 19a,b and 50, and they were used as key intermediates for the syntheses of the target zwitterionic 3-isoxazolols 8-15 and 3-isothiazolols 16 and 17, respectively. These reaction sequences involved different reductive processes. Whereas (RS)-4-amino-3-hydroxy-4,5,6,7-tetrahydro-1,2-benzisoxazole (8, exo-THPO) was synthesized via aluminum amalgam reduction of oxime 22a or 22b, compounds 9, 11-13, and 15-17 were obtained via reductive aminations. Compound 10 was synthesized via N-ethylation of the N-Boc-protected primary amine 25. The enantiomers of 8 were obtained in high enantiomeric purities (ee >/= 99.1%) via the diastereomeric amides 32 and 33, synthesized from the primary amine 23b and (R)-alpha-methoxyphenylacetyl chloride and subsequent separation by preparative HPLC. The enantiomers of 9 were prepared analogously from the secondary amine 27. On the basis of X-ray crystallographic analyses, the configuration of oxime 22a was shown to be E and the absolute configurations of (-)-8 x HCl and (+)-9 x HBr were established to be R. The effects of the target compounds on GABA uptake mechanisms in vitro were measured using a rat brain synaptosomal preparation and primary cultures of mouse cortical neurons and glia cells (astrocytes). Whereas the classical GABA uptake inhibitor, (R)-nipecotic acid (2), nonselectively inhibits neuronal (IC(50) = 12 microM) and glial (IC(50) = 16 microM) GABA uptake and 4,5,6,7-tetrahydroisoxazolo?4,5-cpyridin-3-ol (1, THPO) shows some selectivity for glial (IC(50) = 268 microM) versus neuronal (IC(50) = 530 microM) GABA uptake, exo-THPO (8) was shown to be more potent as an inhibitor of glial (IC(50) = 200 microM) rather than neuronal (IC(50) = 900 microM) GABA uptake. This selectivity was more pronounced for 9, which showed IC(50) values of 40 and 500 microM as an inhibitor of glial and neuronal GABA uptake, respectively. These effects of 8 and 9 proved to be enantioselective, (R)-(-)-8 and (R)-(+)-9 being the active inhibitors of both uptake systems. The selectivity of 9 as a glial GABA uptake inhibitor was largely lost by replacing the N-methyl group of 9 by an ethyl group, compound 10 being an almost equipotent inhibitor of glial (IC(50) = 280 microM) and neuronal (IC(50) = 400 microM) GABA uptake. The remaining target compounds, 11-17, were very weak or inactive as inhibitors of both uptake systems. Compounds 9-13 and 15 were shown to be essentially inactive against isoniazide-induced convulsions in mice after subcutaneous administration. The isomeric pivaloyloxymethyl derivatives of 9, compounds 43 and 44, were synthesized and tested as potential prodrugs in the isoniazide animal model. Both 43 (ED(50) = 150 micromol/kg) and 44 (ED(50) = 220 micromol/kg) showed anticonvulsant effects, and this effect of 43 was shown to reside in the (R)-(+)-enantiomer, 45 (ED(50) = 44 micromol/kg). Compound 9 also showed anticonvulsant activity when administered intracerebroventricularly (ED(50) = 59 nmol).     

A comparison of laparoscopically assisted vaginal hysterectomy and abdominal hysterectomy

The goal of this study was to compare laparoscopically assisted vaginal hysterectomy (LAVH) with total abdominal hysterectomy (TAH). We performed a prospective comparison of the hospital courses of 30 women, 15 undergoing LAVH and 15 undergoing TAH, in a teaching hospital setting. Analysis of variance (ANOVA) was used, with statistical evaluation of differences by Student's t-test for normally distributed data and Kruskal-Wallis for data with dissimilar variances. Fourteen of fifteen patients scheduled for LAVH had their surgery completed without need of a laparotomy. In the LAVH group, (1) mean surgical time was 50 minutes longer, (2) blood loss, complications, and hospital costs were not statistically different, (3) hospital days averaged 1 1/2 less, and (4) postoperative pain ratings and medication requirements were significantly decreased, compared with the TAH group. In many cases, LAVH may be reasonably performed instead of an indicated TAH.     

Correlation between mortality trends of ischaemic cardiopathy and some nutritional factors in Spain 1968–1986

After describing the evolution of mortality from ischaemic cardiopathy (IC) in Spain from 1951 to 1986, which is tending to stabilize in some age groups, and from cerebrovascular accidents (CVA), which is clearly declining, an attempt is made to relate these developments to the prevalence of the main risk factors (hypertension, cholesterol, tobacco) associated with IC and CVA. Certain advances, though of a limited number, have been made in recent years in the control of arterial hypertension in Spain, although campaigns on a national scale as in other countries have not been carried out. Regarding alimentary factors, there is an obvious increase in the consumption of food rich in proteins and animal fats, abandoning to a great extent the traditional Mediterranean diet, with health care action being limited to the improvement of nutrition education of the public. Furthermore, the consumption of tobacco has been increasing in Spain during the study period in spite of health legislation in force in recent years.It is therefore deduced that there is no obvious relationship between mortality due to IC and CVA and the prevalence of the main risk factors associated with these diseases, especially when taking into account that preventive actions on a public health level have been very limited.Corresponding author.     

Influence of incubation time/temperature on acrosome reaction/sperm penetration assay.

The acrosomal status of human spermatozoa was studied in relation to the score of the sperm penetration assay (SPA) at low-temperature (4 degrees C) incubation for induction and synchronization of the acrosome reaction (AR) and the incubation time of spermatozoa in conventional SPA. Spermatozoa were collected from 18 patients, selected by the "swim-up" method and treated in three different ways: (1) short-term incubation group (SIG): 3 h incubation at 37 degrees C, and (2) long-term incubation group (LIG): 20 h incubation at 37 degrees C, and (3) low temperature group (LTG): 24 h incubation at 4 degrees C followed by additional incubation at 37 degrees C for 3 h. The conventional methods of incubation, i.e. SIG (3 h) and LIG (20 h) did not show any significant differences as evaluated by the sperm penetration rate and the number of decondensing sperm heads per oocyte. In contrast, in the LTG all parameters were significantly increased, especially those of penetration rate (p less than 0.0005) and decondensing sperm heads per oocyte (p less than 0.0005). The percentage of AR significantly increased (p less than 0.0005) in the LTG (14.7%) compared with SIG (6.1%) and LIG (10.6%). A significant correlation was demonstrated between AR and the parameters used for evaluation of the SPA. The penetration rate (Spearman test, r = 0.462, n = 54, p less than 0.003) was the most significant parameter correlated with AR. It would appear that only human spermatozoa having completed AR are capable of fusing with the zona-free hamster ova.(ABSTRACT TRUNCATED AT 250 WORDS)     

A new method for evaluation of the acrosome reaction in viable human spermatozoa

The acrosome reaction of human spermatozoa was induced by changes of temperature. Spermatozoa were collected from fertile donors and a patient group, and selected by the "swim-up" method. The spermatozoa were treated in two different ways: Protocol I: 24 hours at room temperature followed by additional incubation at 37 degrees C for 3 hours (control), and protocol II: 24 hours at 4 degrees C followed by additional incubation at 37 degrees C for 3 hours. The acrosome reaction of the viable spermatozoa was evaluated by a new method utilizing indirect immunofluorescence with anti-outer acrosomal membrane antibodies and exposure to a hypo-osmotic medium. In fertile donors as well as in the patient group, significant induction of the acrosome reaction (20%) was evident after exposure to low temperature (4 degrees C). The spontaneous rate of acrosome reaction in the control group was below 7%.