Action of 2-hydroxy-4,6-dimethoxyacetophenone isolated from Sebastiania schottiana

The inhibitory action of the major constituent of Sebastiania schottiana (Euphorbiaceae), 2-hydroxy-4,6-dimethoxyacetophenone (xanthoxyline) on contractions induced by agonists and electrical stimulation of smooth and cardiac muscle preparations was analysed. Xanthoxyline (30 to 300 microM) inhibited contractions of the rat uterus, guinea-pig ileum, and urinary bladder induced by several agonists in a non-competitive, non-selective, concentration-related manner, with the IC50's ranging between 47 and 190 microM. Twitches evoked by electrical-stimulation of strips of guinea-pig longitudinal ileum, urinary bladder, dog ureter, and rat left atrium were also inhibited dose-dependently by cumulative additions of xanthoxyline (IC50's between 50 and 480 microM). Xanthoxyline was found to be a potent inhibitor of spontaneous contractions of the circular smooth muscle layer of the dog ureter, yielding an IC50 of 54 microM. Repeated washing of all preparations completely reversed the inhibitory effects of xanthoxyline. Therefore, it appears that xanthoxyline induces a direct and non-selective inhibition of contractions triggered by agonists or electrical stimulation of smooth and cardiac muscle preparations. The elucidation of the mechanism(s) by which xanthoxyline induced muscle relaxation requires further investigations.     

Lipoid Proteinosis: Case Report

A 20-month-old Kuwaiti girl had manifestations of lipoid proteinosis, a rare autosomal recessive disorder seen more commonly in Caucasians. This condition is diagnosed based on clinical, histopathologic, and ultrastructural criteria. Its biochemical and genetic aspects are still poorly understood.     

Porphyria cutanea tarda associated with autoimmune hypothyroidism, vitiligo and alopecia universalis.

The aetiology of porphyria cutanea tarda (PCT) has not been elucidated, but the possibility of an autoimmune mechanism has been proposed. We report a case of an unknown clinical combination of PCT with autoimmune hypothyroidism, alopecia universalis and vitiligo with thyroid and parietal cell circulating antibodies. This is highly suggestive of underlying autoimmune damage in this patient.     

Age- and Sex-Related Variation in Sensitivity to the Pyrethroid Cypermethrin in the Marine Copepod Acartia tonsa Dana

Acute effects of cypermethrin, a pesticide used to treat ectoparasite infestations of salmon, were assessed using the calanoid copepod Acartia tonsa. A. tonsa has been widely used for hazard assessment of chemicals in the marine environment using acute toxicity tests, but only with randomly selected adults, assuming a sex ratio of 1:1. The present study assesses the environmental hazard of cypermethrin by exposing nauplii and adult males and females, separately. Our results showed that the naupliar stages were 28 times more sensitive to cypermethrin than adults after 96 h of exposure, with LC₅₀s of 0.005 μg L⁻¹ and 0.142 μg L⁻¹, respectively. Significant differences in sensitivity between sexes were only found during the first 24 h of exposure, with males being approximately twice as sensitive as females. The results of age-related variation in sensitivity are supported by studies with other species of copepods and toxicants, where the increased capacity of the adults for detoxification, the allometric differences in weight and size, and the molting process are given as explanations. Variation in sensitivity between sexes is discussed in terms of faster depuration rates in females through egg production and implications of feeding rate changes after 24 h of exposure. Our results suggested that standard toxicity test methods using A. tonsa are unsatisfactory because the most sensitive life stage is not included and sex-related differences in tolerance are not taken into account. We also found that cypermethrin caused significant mortality in Acartia at exposures concentrations from one to three orders of magnitudes lower than the recommended field treatment concentration for copepodic infestations. Received: 27 April 2001/Accepted: 1 July 2001     

Coronary permeability and left ventricular function following thrombolytic therapy

We study 40 patients, 55 +/- 7 years old with acute myocardial infarction treated early by thrombolytic therapy (20 STK and 20 rt-PA). All patients were angiographically studied in the following conditions: 1) baseline, before initiating therapy. 2) Three hours after treatment. 3) Twenty four hours later. 4) Before discharge. The infarct related artery was patent 24 hours after treatment in 31 patients (78%); five of them were patent before treatment, and we observed an early reperfusion in 20 patients (57%) and late reperfusion in 6 patients (17%). The number of patients with angiographic evidence of intraluminal thrombus decreased progressively through conditions while the grade TIMI of coronary perfusion increased in the absence of reocclusion. Final regional wall motion of infarct related myocardial zones and their degree of recovery were significantly higher in recanalized patients, as compared with non-reperfused patients. Similarly, left ventricular functional recovery was higher in patients with antegrade of collateral flow to the infarct area, as compared with totally occluded patients.     

Pulmonary embolism.

Pulmonary embolism (PE) is an important health problem and often a major clinical challenge, not only because of the low specificity of its clinical manifestations but also because of the increasing number of medical circumstances that are risk factors for this illness and the importance of early identification, since prompt and appropriate treatment can decrease mortality from this disease by about 25%. In recent years research on PE has been extensive, directed mainly at trying to determine and characterize its risk factors, establish new clinical probability algorithms, develop new diagnostic methods and put existing ones into perspective, seek new therapeutic approaches (pharmacological and non-pharmacological), and above all establish protocols that can guide the clinician from the stage of clinical suspicion to measures to prevent recurrence. It was the authors' aim to review the most significant literature on this subject, in order to produce a text that reflects the state of the art concerning PE and that can be used as a guide in the clinical approach to this pathology.     

Relationship between resting alpha activity and the ERPs obtained during a highly demanding selective attention task.

In spite of previous reports on the relationship between ongoing EEG and ERPs, there remains a lack of agreement on the nature of their nexuses. The aim of the present study was to evaluate the relationship between resting EEG and the ERP components in two groups of healthy subjects with different levels of performance in a highly demanding selective visual attention task. Young adults were classified according to the amount of their correct responses in the task, into high (HP; averaged hits (AH): 86%) and low performance groups (LP; AH: 59%). EEG was recorded during rest, prior to task performance and absolute (AP) and relative power (RP), as well as inter- (rTER) and intrahemispheric (rTRA) correlation were calculated. ERPs during task performance were also obtained and their amplitude and latency measures were assessed. Results showed that individuals with better behavioral performance had a higher synchronization between both hemispheres during rest as well as higher amplitude and shorter latencies of N2 and P3. Principal Component Analysis revealed that alpha2 AP and RP were inversely related to P2 and N2 latency. Higher values of alpha1 and alpha2 rTER were clustered with higher P3 amplitude and shorter reaction time. In conclusion, the differences in the cortical organization of HP and LP at rest (EEG) seem to be associated to the way the brain reacts during information processing (ERPs).     

Biochemical changes after a qigong program: lipids, serum enzymes, urea, and creatinine in healthy subjects.

BACKGROUND: The aim of the present study was to analyze the effects of a qigong training program on blood biochemical parameters. MATERIAL/METHODS: Twenty-nine healthy subjects participated in the study of whom 16 were randomly assigned to the experimental group and 13 to the control. The experimental subjects underwent daily qigong training for one month. Blood samples for the quantification of biochemical parameters (total cholesterol, HDL, LDL, triglycerides, phospholipids, GOT, GPT, GGT, urea, creatinine) were taken before and after the training program. As statistical analysis, ANCOVA was performed. RESULTS: Statistically significant differences were found showing that the experimental group had lower serum levels of GOT (glutamic-oxaloacetic transaminase), GPT (glutamic-pyruvic transaminase), and urea and that there was a trend towards significance in GGT (gamma-glutamyltransferase). CONCLUSIONS: This study demonstrates that after practicing qigong for the short period of one month, noteworthy changes in several blood biochemical parameters were induced. While it is tempting to speculate on the relevance and implications of these biochemical variations, further investigation is needed to elucidate the scope of these findings.