Dynamics of experimental vasogenic brain oedema in the rat: changes induced by adrenergic drugs

The effects of adrenergic drugs on the formation and resolution of cerebral oedema in a rat model of cold-induced vasogenic brain oedema were studied. Evans blue dye extravasation, water content and ultrastructural alterations (pinocytotic vesicle formation in capillary endothelial cells and apparent water accumulation in the brain parenchyma) were evaluated in parietal cortex. Previous administration of the alpha-adrenoceptor antagonist phenoxybenzamine produced a reduction of Evans blue extravasation and water content, diminished vesicle formation and reduced water accumulation. Previous administration of the beta2-adrenoceptor agonist clenbuterol reduced Evans blue extravasation and water content, but did not change vesicle frequency. The effects of clenbuterol on Evans blue passage to the brain were blocked by timolol (beta-adrenoceptor antagonist) but not by metoprolol (selective beta1-adrenoceptor antagonist). When given after the application of cold, clenbuterol was also able to reduce Evans blue and water content in the brain. Isoprenaline (beta-adrenoceptor agonist that does not cross the blood-brain barrier) showed a reduction in Evans blue extravasation only when given intracerebroventricularly. Vinblastine (a drug that prevents vesicle formation) produced a reduction of the amount of pinocytotic vesicles. We conclude that there is an influence of the central adrenergic nervous system on the formation and/or resolution of vasogenic brain oedema and that the alterations on water movement and Evans blue transport mediated by adrenergic drugs seem to be due, at least in part, to alterations of pinocytotic activity in capillary endothelial cells.     

Saphenous vein graft bypass in the treatment of giant cavernous sinus aneurysms: report of two cases

Two cases of giant intracavernous aneurysms treated by high flow bypass with saphenous vein graft between the external carotid artery (ECA) and branches of the middle cerebral artery (MCA) are presented. Very often these aneurysms are unclippable because they are fusiform or have a large neck. Occlusion of the internal carotid artery (ICA) is the treatment of choice in many cases. This procedure has however a high risk of brain infarction. Revascularization of the brain by extra-intracranial anastomosis between the superficial temporal artery (STA) and branches of the MCA is frequently performed. This procedure provides however a low flow bypass and brain infarction may occur. We report two cases of giant cavernous sinus aneurysms treated by high flow bypass and endovascular balloon occlusion of the ICA. Immediate high flow revascularization of MCA branches was achieved and the patients showed no ischemic events. Follow-up of 8 and 14 months after operation shows patency of the venous graft and no neurological deficits. Angiographic control examination showed complete aneurysm occlusion in both cases.     

Associations of substance use, abuse, and dependence with subsequent suicidal behavior

General population survey data are used to disaggregate the associations of substance use disorders with suicide attempts in order to evaluate a number of hypotheses about the processes leading to these associations. Data are from the US National Comorbidity Survey (1990-1992). Discrete-time survival analysis is used to study the effects of retrospectively reported temporally prior substance use, abuse, and dependence in predicting first onset of suicidal behavior. Alcohol and drug use predict subsequent suicide attempts after controlling for sociodemographics and comorbid mental disorders. Previous use is not a significant predictor among current nonusers. Abuse and dependence are significant predictors among users for three of the 10 substances considered (alcohol, inhalants, and heroin). The number of substances used is more important than the types of substances used in predicting suicidal behavior. Disaggregation shows that the effects of use are largely on suicidal ideation and nonplanned attempts among ideators. In comparison, the effects of use on suicide plans and planned attempts among ideators are not significant. Clinicians need to be aware that current substance use, even in the absence of abuse or dependence, is a significant risk factor for unplanned suicide attempts among ideators.     

Suicide attempts in a sample of patients from a general hospital

BACKGROUND: Suicide in Mexico has risen steadily in recent years, increasing by 156% in the last two decades. The study of suicide precursors, such as suicide attempts, has also become an important public health topic. The aim of this study is to establish the prevalence of suicide attempts in a general hospital setting and its association with alcohol, depression, and other factors. METHODS: A cross-sectional survey of a sample of patients was carried out in all three service units (inpatient, outpatient, and the emergency room) of a general hospital in Mexico City. All patients were randomly selected to participate regardless of the reason for initial hospital admission. Each patient was administered a series of psychological and demographic scales including the Beck Depression Inventory, the Beck Hopelessness Inventory, the General Health Questionnaire, a suicide assessment scale, a scale for alcohol consumption, and several measurements of alcohol-related problems. RESULTS: The final sample was made up of 1,094 patients of both genders (68% women), aged 18-65 years. A lifetime prevalence of suicide attempts of 6.1% (95% confidence interval [CI] of 4.7-7.7%) was found. Multiple logistic regression was used to obtain estimations of the association between lifetime suicide attempt and other factors. Marital status, age, depressed mood, hopelessness, Goldberg's 30-item version of the General Health Questionnaire, and high levels of alcohol consumption were all associated with the suicide attempt. CONCLUSIONS: Prevalence of lifetime suicide attempts was mainly related to being young, divorced, or widowed, and to feeling depressed, hopeless, and under undesirable psychological distress.     

Postnatal development of pups from nursing rats treated with Gingko biloba

The Gingko biloba extract is contraindicated during pregnancy and lactation due to the lack of information about its effects on these reproductive phases. Previous studies have shown that G. biloba extract contains components with estrogenic and antiestrogenic activities, thus nursing dams treated with the extract of this plant could show reduction in milk production, resulting in malnutrition and poor development of pups. This work analyzes the postnatal development of pups, whose mothers were treated with G. biloba extract during the lactation period. Nursing Wistar rats received 3.5 mg/kg/day of G. biloba aqueous extract, corresponding to the highest human dose. Clinical signs of maternal toxicity were evaluated. The growth rate, viability, survival during treatment and lactation indices of the pups were calculated. The physical, motor and sensorial development of the pups was also evaluated. No maternal signs of toxicity were observed. As there were no biological differences between control and G. biloba treated pups, it is possible to assume that, in this experimental design, the administration of G. biloba aqueous extract to nursing rats during the lactation period seems to be devoid of toxic effect to mothers and to the physical, motor and sensory development of the pups.     

The opposing effects of the flavonoids isoquercitrin and sissotrin, isolated from Pterospartum tridentatum, on oral glucose tolerance in rats

The effect of an aqueous extract of Pterospartum tridentatum on the blood glucose levels of normal Wistar rats was investigated in a situation of oral glucose challenge. The extract at 300 mg/kg showed an antihyperglycaemic effect in the first 30 min after glucose challenge but then the blood glucose levels rose above those of the control group, indicating the presence of compounds with different effects on glucose tolerance. Nine compounds of isoflavone and flavonol skeletons were identified in the extract by HPLC-ESI-MS(n), four of them being identified for the first time in this species. The isoflavone sissotrin and the flavonol derivative, isoquercitrin, were selected for the oral glucose tolerance test. Isoquercitrin (100 mg/kg) showed time-dependent antihyperglycaemic activity by delaying the post-oral glucose load glycaemic peak at 30 min, as did the sodium-dependent glucose transporter inhibitor phloridzin (100 mg/kg). In contrast, sissotrin (100 mg/kg) showed an opposite effect, impairing glucose tolerance. In conclusion, these preliminary results indicate that the effect of the extract on blood glucose may be either antihyperglycaemic or hyperglycaemic. Additionally, as far as is known, these are the first in vivo results on the acute antihyperglycaemic potential of isoquercitrin.     

Casuística del carcinoma intraductal de mama en el Hospital Universitario Son Dureta

Objective

To determine the incidence rates and clinical presentation of ductal carcinoma in situ of the breast, as well as its pathologic characteristics, the forms of treatment used, and outcomes.

Subjects and method

We performed a retrospective study with review of 83 consecutive patients with a histopathological diagnosis of ductal carcinoma in situ (DCIS) of the breast from January 1st, 1990 to December 31st, 2004 in the Son Dureta University Hospital in Palma, Majorca.

Results

Breast DCIS accounted for 3.5% of all breast carcinomas identified in our hospital in the previous 15 years. The most frequent age at diagnosis ranged from 50 to 64 years. Seventy-two percent of the lesions were detected by mammography. Total mastectomy was performed in 57% of the patients, and treatment with breast preservation was carried out in 37%. The recurrence rate was 4%, with an overall survival rate of 100%.

Conclusions

Screening mammography identifies very small cancers. Involvement of the surgical margins is a determining factor for local treatment of breast cancer and is an accurate predictor of risk of recurrence. Disease-free survival is almost 100% in patients undergoing mastectomy, although the preferred therapy in cases of DCIS is local treatment with breast conservation.