Purification and characterization of a mammalian toxin from venom of the Mexican scorpion,Centruroides limpidus tecomanus Hoffmann

The venom from the scorpion Centruroides limpidus tecomanus Hoffmann was obtained by homogenization of entire telsons and electrical stimulation of anaesthetized animals. Both venom preparations contain toxic proteins to mice and were separated in a Sephadex G-50 column followed by carboxymethyl-cellulose chromatography. At least two toxic fractions were resolved from the homogenized telsons and three toxic fractions from the venom obtained by electrical stimulation. Rechromatography of the latter fractions on an ion exchange column (Aminex A-5) gave a homogeneous toxin called II.9.3, which on amino acid analysis was shown to be composed of 65 residues with a calculated mol. wt of 7335. The N-terminal sequence is H-Lys-Glx-Gly-X-Leu-Val-Asx-His-X-Thr-Gly-Cys-…, homologous to other scorpion toxins. The venom obtained by electrical stimulation was further characterized; the fraction I from the Sephadex G-50 chromatography shows hyaluronidase activity, although the fraction III shows at least 15 different components positive to ninhydrin, after separation by peptide mapping techniques.     

Lateral approach to the sciatic nerve block in the popliteal fossa: correlation between evoked motor response and sensory block

BACKGROUND AND OBJECTIVES: The purpose of this study was to identify which of two motor responses of the foot (plantar flexion versus dorsiflexion) best predicts complete sensory blockade of the sciatic nerve when is used for lateral popliteal sciatic nerve block. METHODS: Thirty American Society of Anesthesiologist physical status I or II patients scheduled for foot and ankle surgery under lateral popliteal sciatic nerve block were enrolled in the study. During each block, the needle was placed to evoke one of the following motor responses of the foot: plantar flexion or dorsiflexion. Thirty milliliters of 0.75% ropivacaine was injected after the motor response was elicited at <0.5 mA. The sequence of elicited motor response was randomized. Sensory blockade of the areas of the foot innervated by the deep peroneal, superficial peroneal, posterior tibial, and sural nerves was checked in a blinded manner. Time required for onset of sensory and motor block of the foot was recorded. RESULTS: The 2 groups were similar with regard to demographic variables and type of surgery. The total of nerves blocked (deep and superficial peroneal, posterior tibial, and sural nerves) after elicited plantar flexion was greater (complete sensory block in 58 of 60 nerve distributions) than after elicited dorsiflexion (34 of 60 nerve distributions) (P <.05). Onset of complete sensory and motor blockade of the foot was faster after elicited plantar flexion (16.6 +/- 5.1 minutes, 20.1 +/- 5.1 minutes, respectively) than after elicited dorsiflexion (24.3 +/- 5.1 minutes, 28.1 +/- 5.0 min, P <.05). CONCLUSIONS: After stimulation of the sciatic nerve, plantar flexion better predicts complete sensory blockade of the foot than dorsiflexion when using the lateral approach to the popliteal fossa. The findings of the present study apply to a single injection of 30 mL of ropivacaine 0.75%.     

Effects of perinatal exposure to delta 9-tetrahydrocannabinol on operant morphine-reinforced behavior

The present study examined the effects of Delta(9)-tetrahydrocannabinol (Delta(9)-THC) when administered during the perinatal period on morphine self-administration in adulthood. To this end, pregnant Wistar rats were daily exposed to Delta(9)-THC from the fifth day of gestation up to pup weaning, when they were separated by gender and left to mature to be used for analyses of operant food- and morphine-reinforced behavior in a progressive ratio (PR) schedule. We also analyzed dopaminergic activity (DOPAC/DA) in reward-related structures during specific phases of the behavioral study. In both reinforcement paradigms, food and morphine, females always reached higher patterns of self-administration than males, but this occurred for the two treatment groups, Delta(9)-THC or vehicle. These higher patterns measured in females corresponded with a higher DOPAC/DA in the nucleus accumbens prior to the onset of morphine self-administration in comparison to males. Interestingly, DOPAC/DA was lower in Delta(9)-THC-exposed females compared to oil-exposed females and similar to oil- and Delta(9)-THC-exposed males. In addition, Delta(9)-THC-exposed females also exhibited a reduction in DOPAC/DA in the ventral tegmental area, which did not exist in males. All these changes, however, disappeared after 15 days of morphine self-administration and they did not reappear after 15 additional days of extinction of this response. Our data suggest that females are more vulnerable than males in a PR schedule for operant food and morphine self-administration; perinatal Delta(9)-THC exposure is not a factor influencing this vulnerability. The neurochemical analysis revealed that the activity of limbic dopaminergic neurons prior to morphine self-administration was higher in females than males, as well as that the perinatal Delta(9)-THC treatment reduced the activity of these neurons only in females, although this had no influence on morphine vulnerability in these animals.     

What do patients think about anesthesia? Survey on postoperative satisfaction in ambulatory surgery comparing general and subarachnoid anesthesia

OBJECTIVES: To conduct a telephone survey to determine the degree of patient satisfaction with the anesthetic technique applied during outpatient arthroscopic surgery on the knee. MATERIAL AND METHODS: We recorded refusals to respond to the survey and the reasons. The patients were distributed randomly in 3 groups to receive 1) general anesthesia with propofol and remifentanil by continuous intravenous infusion at rates of 2 and 0.2-0.4 microgram/Kg/h, respectively; 2) subarachnoid anesthesia with lidocaine, and 3) subarachnoid anesthesia with 1.5% prilocaine. The second and third group received fixed doses of 3 mL of the local anesthetic. All patients were telephoned 48 hours after surgery and asked to answer 8 questions concerning prior experience of anesthesia, degree of satisfaction with the type of anesthesia used, postoperative pain, quality of information received about the anesthetic procedure, and undesirable side effects. RESULTS: We interviewed 120 patients and 32 refused to participate. All patients in the general anesthesia group would accept the same anesthetic technique again in future operations, whereas 85% and 82% in the lidocaine and prilocaine groups, respectively, would accept the same technique (p = 0.026). Satisfaction with anesthesia, postoperative pain, and quality of information about the anesthetic procedure was similar in all 3 groups. No important undesirable side affects were reported in any of the groups. CONCLUSIONS: The overall satisfaction with various types of anesthesia is similar among outpatients undergoing arthroscopic surgery on the knee; therefore, patient preferences for one technique over another should be taken into more consideration.     

Speciation of heavy metals in recent sediments of three coastal ecosystems in the Gulf of Cádiz, southwest Iberian Peninsula

A live-step sequential extraction technique was used to determine the partitioning of Cr, Mn, Fe, Cu, Zn, Cd, and Pb among the operative sedimentary phases (exchangeable ions, carbonates, manganese and iron oxides, sulfides and organic matter. and residual minerals) in coastal sediment from three locations in the southwest Iberian Peninsula. Two sites are located close to industrial areas, the salt marshes of the Odiel River and Bay of Cádiz, and one in a nonindustrial area, the Barbate River salt marshes. The Odiel River salt marshes also receive the drainage from mining activities in the Huelva region. In the sediments from the Bay of Cádiz and Barbate River salt marshes, Cr, Cu, Fe, and Zn were extracted from the residual fraction at percentages higher than 60%. In the sediments from the Odiel River salt marshes, concentrations of all the metals, except Cu. Zn, and Cd, exceeded 60% in the residual fraction as well. In the sediments from the Bay of Cádiz and Barbate River salt marshes, the main bioavailable metals were Mn and Cd; in those from the Odiel River salt marshes, the main bioavailable metals were Zn and Cd, respectively. The environmental risk was determined by employing the environmental risk factor (ERF), defined as ERF = (CSQV - Ci/CSQV), where Ci is the heavy metal concentration in the first four fractions and CSQV is concentration sediment quality value (the highest concentration with no associated biological effect). Our results showed that the sediments from the Cádiz Bay and Barbate River salt marshes do not constitute any environmental risk under the current natural conditions. In contrast, in the Odiel River salt marshes, Cu, Zn, and Pb yielded ERFs of less than zero at several sampling stations and, consequently, pose a potential threat for the organisms in the area. This is a consequence of the high levels of metals in the area derived from the mining activity (pyrite) and industrial activities and the association of these heavy metals with more labile fractions of the sediments.     

Relative roles of ICAM-1 and VCAM-1 in the pathogenesis of experimental radiation-induced intestinal inflammation

PURPOSE: Cell adhesion molecules mediate leukocyte recruitment into the irradiated organs; modulation of this process may protect from radiation damage. Our objective was to characterize the requirement for intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1) in intestinal inflammatory response after abdominal irradiation. METHODS AND MATERIALS: Endothelial ICAM-1 and VCAM-1 expression was determined using radiolabeled antibodies in mice 24 h and 14 days after irradiation with 10 Gy, or sham radiation. Leukocyte-endothelial cell interactions in intestinal venules were assessed using intravital microscopy, and the function of ICAM-1 and VCAM-1 in this process by using blocking antibodies and ICAM-1(-/-) mice. RESULTS: The number of adherent leukocytes significantly increased 24 h after irradiation and remained elevated at 14 days. Treatment with anti-ICAM-1 antibodies and ICAM-1 genetic deficiency significantly reduced leukocyte adhesion 24 h after irradiation. At 14 days after irradiation, both wild-type and ICAM-1(-/-) mice had an upregulation of VCAM-1, expression, and VCAM-1 immunoneutralization, but not ICAM-1 immunoneutralization, significantly reduced leukocyte adhesion. In ICAM-1(-/-) mice, regeneration of the intestinal epithelium was enhanced relative to wild-type mice. CONCLUSIONS: ICAM-1 plays a key role in leukocyte recruitment at early time points after abdominal irradiation, whereas VCAM-1 is the main molecular determinant of leukocyte recruitment at late time points.     

VR1-positive primary afferents contact NK1-positive spinoparabrachial neurons

Neurons in rat superficial dorsal horn that express neurokinin receptor 1 (NK1), a receptor for substance P, play a critical role in the development of hyperalgesia. Thermal hyperalgesia is dramatically reduced after ablation of these neurons, but, paradoxically, not in mice that lack the NK1 receptor (Mantyh et al. [1997] Science 278:275-279). Because primary afferents that express vanilloid receptor 1 (VR1), a receptor for noxious heat, are essential for thermal nociception and hyperalgesia, we reasoned that VR1-positive fibers may terminate onto NK1-expressing dorsal horn neurons. We therefore combined immunofluorescent staining for VR1 and NK1 to show that NK1-positive neurons in lamina I are contacted by VR1-positive fibers. That these contacts represent synapses was verified by staining for the presynaptic marker synaptophysin and by electron microscopy. By combining retrograde tracing with immunocytochemistry, we also found that most NK1-positive cells contacted by VR1-positive fibers project to the lateral parabrachial nucleus. Because quantitative evaluation suggests a preferential targeting of NK1-positive lamina I neurons by fibers containing VR1, these results demonstrate a significant monosynaptic innervation of spinoparabrachial neurons by VR1-positive afferents.     

Afferent and efferent connections of the cerebellum of the chondrostean Acipenser baeri: a carbocyanine dye (DiI) tracing study

The afferent and efferent connections of the cerebellum of the primitive bony fish Acipenser baeri were studied in fixed brains with a fluorescent lipophylic carbocyanine (DiI). The three regions of the cerebellum (the auricles, valvula, and corpus) showed similar afferents, mostly originated from extensive precerebellar populations of the midbrain tegmentum and from the inferior olive. A pretectal nucleus was also labeled after DiI application to the three regions of the cerebellum. However, DiI application to the pretectal region revealed that the pretectocerebellar projection mainly targeted to the caudal region of the corpus cerebelli. Some precerebellar cells were observed in the torus semicircularis, isthmic central gray, and rhombencephalic reticular formation. Primary fibers of the anterior lateral line nerve and neurons of the octavolateral area also project to the auricle. After DiI application to the auricles, most ascending efferents coursed to the region of the nucleus of the medial longitudinal fascicle and thalamus, mostly contralaterally. Ipsilateral descending fibers were also labeled in the medullary octavolateral area. Application of DiI to the nucleus of the medial longitudinal fascicle revealed three clusters of cerebellar projection neurons located in the granular layers of the auricles, valvula, and corpus cerebelli, mostly contralateral to the application site. These cerebellar projection neurons did not exhibit a number of characteristics of teleost eurydendroid cells (i.e., the cerebellar efferent cells of teleosts), such as the presence of spiny dendrites ascending to the molecular layer. Comparison of the afferent and efferent projections of the sturgeon cerebellum with those reported in teleosts supports the hypothesis that some traits observed in the teleost cerebellar system represent recent evolutionary developments.     

Carcinoma epidermoide primario de mama

Primary squamous cell carcinoma of the breast is an infrequent tumour, that requires to rule out a tumor from other location to be diagnosed. Several characteristics as big size, and necrosis or cyst presence, have been associated rather than adenocarcinoma, although clinic and radiological squamous cell carcinoma non-specific characteristics are difficult to distinguish from adenocarcinomas. We present a woman with a 4-cm primary squamus cell carcinoma of the breast. Pathogenic, diagnostic, and therapeutic aspects in accordance with medical literature, are discussed.