Optical, Electrical, and Morphologic Characterization of Chromium-Impurified CdS Thin Films Elaborated by the Chemical Bath Deposition.

In this research work, a material system formed of cadmium sulfide combined with chromium atoms was developed to evaluate the influence of chromium concentration on the optical, electrical, structural, and morphological properties of a precursor layer of CdS. It is possible to observe that the transmission spectra increased for all chromium concentrations analyzed. From X-ray diffractograms, we conclude more accurately that CdS presents a mixture of phases, including orthorhombic, hexagonal, and cubic. Furthermore, the impact of adding chromium results in variations in the intensity of two major peaks in the diffractograms and an anomalous shift in the CdS pattern. The calculated resistivities show an invariable behavior of 4.5 × 106 Ω cm. In addition, the bandgap values remain practically constant, with values of approximately 2.43-2.44 eV. The addition of chromium at different concentrations leads to surface morphology changes, as observed in SEM images.

Fresh cow mastitis monitoring on day 3 postpartum and its relationship to subsequent milk production.

The purpose was to determine the association of milk California Mastitis Test (CMT), somatic cell concentration (SCC), and milk differential cell count results on day 3 postcalving with subsequent lactation production and health events. On d 3 postcalving, the CMT was performed and quarter milk samples were collected from 130 dairy cows. Quarter SCC and milk differential cell counts were determined. Microbiology on duplicate quarter milk samples was used to determine the presence of intramammary infection by major or minor pathogens. Production measures obtained using Dairy Herd Improvement Association testing were 150-d standardized and summit milks. Milk culture results on a cow basis included 82 (63.1%) samples with no growth, 31 (23.9%) with major pathogens, and 17 (13.1%) with minor pathogens. Milk culture results comparing cows with no growth to those with any growth (major or minor pathogens) were not associated with statistically significant differences in milk production. Milk culture results comparing cows with major pathogens to those with no growth and minor pathogens combined were associated with statistically significant differences in 150 d milk. Milk production did not differ for cows with CMT results above and below a cut-off of trace, and for SCC results above and below cut-offs of 200,000, 300,000, and 400,000/mL, respectively. Statistically significant differences in milk production were found for cows above and below cut-offs for percentage neutrophils in milk and for absolute neutrophil counts. Associations were found for milk production and number of quarters (0, 1, 2, or 3 and 4 combined) above respective cut-offs for SCC, percentage neutrophils in milk, and absolute numbers of neutrophils in milk, but not for CMT. Milk production differed for cows experiencing any health event versus those with no health event. The most commonly recorded health event was clinical mastitis. Statistically significant associations were detected between health events and milk culture results, SCC, neutrophil percentage, and neutrophil absolute counts. Results of the present investigation indicate that milk monitoring on d 3 of lactation using milk neutrophil percentage or neutrophil absolute counts may be useful as an indication of subsequent milk production.

Expression of genes, encoding the enzymes of cysteine metabolism in human placenta in the first and third trimesters of uncomplicated pregnancy.

The cellular cysteine is highly regulated in a narrow range of concentrations due to its cyto- and neurtoxicity when it is overwhelmed or its deficiency for protein synthesis and other vital metabolic reactions when its amount is restricted. The regulation of cysteine content and its metabolic products, glutathione, taurine and inorganic sulfur compounds, is scarcely explored in human placenta though cysteine metabolism is closely related to the maintenance of redox status and protection from free radical oxidation, elimination of homocysteine and detoxification. These processes are particularly important for placenta which meets substantial changes of oxygen supply during its development, and is the last metabolically active organ between mother and fetus. The abundance of CDO , CSAD , ADO , SUOX, GCLC and GCLM mRNAs was estimated by RT -qPCR and compared with the computationally analyzed microarray gene expression data from GEO , while the level of individual protein ­ by western-blot analysis, both in placental samples from first and third trimesters of uncomplicated pregnancies. The abundance of CDO mRNA is significantly up-regulated at term compared to the first trimester, the level of GCLM and GCLC mRNAs remains almost unchanged while the abundance of other mRNAs reduces to varying degrees. Overall, the changes of gene expression in third trimester in comparison to the first one estimated by RT-qPCR and microarray coincide while the former data are more informative for the limited group of genes. The data provide the basis for further research of these genes expression and phenotype of human placenta in health and disease

Cytokine profiles of stimulated blood lymphocytes in asthmatic and healthy adolescents across the school year.

T cell cytokines play an important role in mediating airway inflammation in asthma. The predominance of a Th2 cytokine profile, particularly interleukin (IL)-4 and IL-5, is associated with the pathogenesis and course of asthma. The aim of this study was to test the hypothesis that a stressful life event alters the pattern of cytokine release in asthmatic individuals. Thirteen healthy controls and 21 asthmatic adolescents gave blood samples three times over a semester: midsemester, during the week of final examinations, and 2-3 weeks after examinations. Interferon-gamma (IFN-gamma), IL-2, IL-4, and IL-5 were measured from supernatants of cells stimulated with PHA/PMA for 24 h. Cells from asthmatic subjects released significantly more IL-5 during the examination and postexamination periods, whereas cells from healthy controls released significantly more IL-2 during the midsemester and examination periods, thereby indicating a bias for a Th2-like pattern in asthmatics and a Th1-like pattern in healthy controls. IL-4 and IL-5 production showed a marked decrease during and after examinations in healthy controls, whereas this decline was absent in asthmatics. The ratios of IFN-gamma:IL-4 and IFN-gamma:IL-5 also revealed significant changes in the profile of cytokine release across the semester. These results indicate differential cytokine responses in asthmatics that may become pronounced during periods of cellular activation.

High dose rate transperineal interstitial brachytherapy for cervical cancer: high pelvic control and low complication rates.

PURPOSE: To report the clinical outcome for cervical carcinoma treated with external beam pelvic radiotherapy and interstitial high dose rate (IS-HDR) brachytherapy. METHODS AND MATERIALS: Between July 1991 and June 1996, 62 patients with locally advanced stage cervical carcinoma or early stage carcinoma that precluded satisfactory tandem and ovoid insertion were treated. Most patients received 36 Gy (range: 25 Gy-45 Gy) external beam radiotherapy (EBRT) to the pelvis prior to brachytherapy implant. EBRT was continued, with central shielding, to a dose of 50 Gy to the pelvic sidewalls. HDR Iridium-192 brachytherapy was given in 6 fractions of 5.5 to 6.0 Gy. The mean follow-up was 40 months. RESULTS: Stage distribution was: Stage IB (12), Stage IIA (1), Stage IIB (26), Stage IIIA (6), Stage IIIB (13), and Stage IVA (4). The overall local tumor control was 94%. Local control rates by FIGO stage were Stage I (12/12) 100%, Stage II (25/27) 93%, Stage III (18/19) 95%, and Stage IV (3/4) 75%. The regional pelvic control rates were overall 81%, Stage I (12/12) 100%, Stage II (22/27) 81%, Stage III (15/19) 79%, and Stage IV (1/4) 25%. Distant metastasis developed in 20 patients (32%). The actuarial 5-year disease-free survival was for all patients 48%, Stage I 81%, Stage II 47%, Stage III 39%, and Stage IV O%. Grade 3-4 delayed morbidity resulting from treatment, occurred in 6.5% (4/62) of patients. A fistula without local recurrence occurred in 1.6% (1/62) patients. CONCLUSIONS: We report excellent local and regional pelvic control results using a 6 fraction IS-HDR brachytherapy protocol for cervical carcinoma. The incidence of severe complications is low and suggests that a consistent brachytherapy technique and multiple HDR fractions are therapeutically advantageous to patients treated for cervical carcinoma.

High dose rate prostate brachytherapy: the California Endocurietherapy (CET) method.

BACKGROUND AND PURPOSE: To describe the rationale, protocol and procedure for the treatment of prostate cancer using high dose rate brachytherapy (HDR-BT) and a non-fixed template technique. MATERIALS AND METHODS: Between July 1991 and December 1998, 491 patients with carcinoma of the prostate were treated using HDR-BT and a non-fixed template technique. AJC stages T(1C)-T(3B), patients with prior transurethral resections of the prostate (TURP) and gland volumes >60 cm(3), were included. Flexible cystoscopy, fluoroscopy and transrectal ultrasound (TRUS) were used and 17 flexiguides were inserted through the perineum. Dosimetry was carried out using localization films. Treatment volume was defined at 4-6 mm outside the peripheral catheters. BT consisted of two implants, separated by 1 week, with two fractions given per implant for a total of four HDR fractions. Dose prescription to the treatment volume was 6 Gy (HDR) per fraction, with an additional dose of 0.5 to 0.75 Gy given where required. RESULTS: Patients with glands >60 cm(3), narrow pubic arches and TURP defects were treated satisfactorily. Symptoms of urinary irritation occurred with variable intensity and abated rapidly 2 weeks after the procedures. There was no high-grade chronic rectal morbidity and most patients reported no rectal symptoms or treatment-related chronic urinary incontinence. CONCLUSIONS: The non-fixed template technique allowed flexibility in flexiguide placement to encompass large glands (>60 cm(3)), extracapsular extension and seminal vesicle involvement without the need for additional flexiguides. Also, small pubic arches and TURP defects posed little problem in positioning the flexiguides. This versatility resulted in complete treatment volume coverage of the prostate.

High dose rate brachytherapy in the treatment of prostate cancer.

Because the HDR brachytherapy treatments are delivered within minutes and on an outpatient basis, HDR brachytherapy is very well tolerated by patients and offers complete radiation safety. Published studies2, 11, 12, 13, 16, 17, 18, 22, 24, 25 have shown high local clinical and biochemical control rates. Chronic complications have been acceptably low. Very low rates of urinary incontinence and high sexual potency rates have been reported. Gastrointestinal morbidity has been minimal. The development of Ir-192 HDR afterloading brachytherapy and refinements in the dosimetry have ushered in a new era in prostate brachytherapy. The control of the radiation dose and the ability to shape the radiation treatment envelope using a stepping source have allowed a giant step forward in radiation oncology technology. It is now possible to deliver tumoricidal doses of radiation conformally to the prostate while minimizing the dose to the bladder, urethra, and rectum. At present, HDR afterloaded brachytherapy is the optimal whole-organ and tumor-specific conformal radiation therapy for prostate cancer.

Offspring of streptozotocin diabetic rats: size changes in Langerhans islets with time after birth.

It has been demonstrated that, in the diabetic rat, pregnancy and lactation are severely altered: in this study, we have measured the size of Langerhans islets of rat pups, the offspring of experimental diabetic mothers and nondiabetic controls. Diabetes was induced through streptozotocin administration (dose, 60 mg/kg body wt.). This drug was injected in every animal; their blood sugar was measured 1 week later (Haemo-Glukotest, Boehringer Mannheim), and they were then separated into three groups according to their fasting blood sugar levels: (a) severe diabetics (above 16.5 mM/l); (b) mild diabetics (6.5-16.5 mM/l); and (c) nondiabetic normals. They received insulin therapy (2-4 I.U./day) as the mild diabetics exhibited a slightly higher than normal fasting blood sugar, and the diabetic ones, above 15 mM/l. The areas of Langerhans islets of pups were measured 1 and 5 days after parturition; pancreas sections were dyed (haematoxylin-eosin) and morphometry was then performed using a digitalized magnetic tabloid connected to a Zeiss Morphomat 30 (Kontron). On the first day after parturition, the pancreas section areas in pups from mildly and severely diabetic mothers were smaller than those in neonates from nondiabetic controls (P < 0.001). The areas in neonates from severely diabetic mothers showed a more intense decrease than those from mildly diabetic animals (P < 0.01). On day 5 after delivery, the areas of Langerhans islets in offspring from normal mothers decreased and those in pups from diabetic mothers tended to normalize (P < 0.01), particularly those from the severely sick group (P < 0.01). We conclude that after parturition the offspring is no longer exposed to the high blood sugar levels found in both diabetic groups of mothers, thereby no hyperinsulinemia is needed; as time elapses, then, the area of their Langerhans islets tends to normalization.

Effect of ovarian hormones upon liver mitochondrial function in diabetic rats.

In the present study it is shown that streptozotocin (SZ)-induced chronic diabetes of female albino rats produced significant alterations in liver mitochondrial function after 30-35 days of diabetes. The disturbances were as follows: (1) a significant fall of the mean values of the respiratory control ratio and of state 3 of respiration using three substrates, 3-hydroxybutyrate, malate-glutamate and succinate, and (2) a significant increase of the mean damping factor of the oscillatory osmotic variations (with valinomycin as K+ ionophore and succinate as substrate). The same mitochondrial function parameters were analyzed for comparison in control non-diabetic rats (group N) and in the following groups of female rats with chronic diabetes: intact (group I), oophorectomized (6 days after the injection of SZ) (group O), and oophorectomized with restitution therapy of 17 beta-estradiol (from the operation until the day before killing) (group O + Eol). The O group showed significantly higher values of the respiratory control ratio and of state 3 of respiration and significantly lower damping factors than group I. The restitution treatment in the O + Eol group restored the mitochondrial functions assayed to values similar to those of group I. These data provide strong evidence that estrogens exert a negative effect at the molecular level upon impaired liver mitochondrial functions in SZ-induced diabetes.

Favourable, significant effect of the dose-dependent treatment with RU 38486 (RU) on the alterations of the hepatic mitochondrial function of diabetic rats.

In the present work, the effect "in vivo' of increasing doses of RU 38486 upon the hepatic mitochondrial function of diabetic rats has been studied. At the same time, the action of adrenalectomy and corticosterone restitution on this function were comparatively demonstrated. The parameters measured were oxygen consumption with the substrates: 3-hydroxybutyrate (HB), succinate (Suc) and malate-glutamate (Mal-glut) in intact liver mitochondria and the activities of 3-hydroxybutyrate dehydrogenase (HBD) and cytochrome c oxidase (Cyt.c oxid.) enzymes in broken liver mitochondria. The groups of animals studied were normal controls (N) and the following groups of diabetic rats: rats without any treatment (D), adrenalectomized rats (D+ADX), rats that were adrenalectomized and treated with corticosterone (D+ADX+C) and four groups treated with increasing oral doses of RU (in mg/kg body wt.), that is, 12.5 (D+RU1), 25.0 (D+RU2), 37.5 (D+RU3) and 50.0 (D+RU4). The results showed a tendency of increasing values of mitochondrial oxygen consumption in diabetic animals treated with RU. The favourable effect of increasing doses of RU on O2 consumption of diabetic rat liver mitochondria with each of the substrates showed a significant association as indicated by the values obtained for the correlation coefficients r (0.95, 0.97 and 0.99 according to the substrate HB, Succ or Mal-glut, respectively). Likewise, the correlation between the treatment with increasing doses of RU and the recovery of enzyme activities showed a significant dose-effect association with r 0.94 for HBD and r = 0.95 for Cyt.c oxid. Adrenalectomy showed a similar effect to treatment with the maximum dose of RU while corticosterone restitution gave measured values similar to those of the D group. In conclusion, the favourable, significant variation of the hepatic mitochondrial function of diabetic rats was demonstrated by the dose-dependent treatment with RU as seen by the correlation statistical study performed. At the same time, the pernicious effect that glucocorticoids exert upon such function in experimental diabetes was confirmed.

Effects of diet composition on the metabolic and heart rate responses to cold water exposure in men.

The reaction to immersion in cold water (22 degrees C) was studied in ten healthy male volunteers successively receiving balanced (C), hypercarbohydrate (HC), hyperprotein (HP), and hyperlipid (HL) normocaloric diets with a three week equilibration period on each diet. Oxygen consumption (ml min-1 m-2) increased from 149 to 224 during C, from 160 to 196 during HL, from 154 to 178 during HP, and from 166 to 187 during HL. Only the first two differences were significant. Pulmonary ventilation (ml min-1 m-2) increased from 4.08 to 6.24 during C, from 4.01 to 5.48 during HC, from 3.41 to 3.83 during HP, and from 3.77 to 5.48 during HL. The difference was statistically significant only for C. Heart rate (beats/min) decreased from 73 to 64 during C, from 74 to 61 during HC, from 73 to 60 during HP and from 72 to 64 during HL. The differences were statistically significant for all diets except HL. Oral temperature decreased in all groups (range 0.4 to 1.6 degrees C). Respiratory rate changes were not statistically significant. The calorigenic reaction to cold water immersion was demonstrable for all groups but more efficient in subjects receiving either balanced or HC diets, suggesting that HP and HL diets reduce cold adaptation.

Chemical extraction methods to assess bioavailable arsenic in soil and solid media.

Soil ingestion by children is an important pathway in assessing public health risks associated with exposure to arsenic-contaminated soils. Soil chemical methods are available to extract various pools of soil arsenic, but their ability to measure bioavailable arsenic from soil ingestion is unknown. Arsenic extracted by five commonly used soil extractants was compared with bioavailable arsenic measured in vivo by immature swine (Sus scrofa) dosing trials. Fifteen contaminated soils that contained 233 to 17 500 mg kg(-1) arsenic were studied. Soil extractants were selected to dissolve surficially adsorbed and/or readily soluble arsenic (water, 1 M sodium acetate, 0.1 M Na2HPO4/0.1 M NaH2PO4) and arsenic in Fe and Mn oxide minerals (hydroxylamine hydrochloride, ammonium oxalate). The mean percent of total arsenic extracted was: ammonium oxalate (53.6%) > or = hydroxylamine hydrochloride (51.7%) > phosphate (10.5%), acetate (7.16%) > water (0.15%). The strongest relationship between arsenic determined by soil chemical extraction and in vivo bioavailable arsenic was found for hydroxylamine hydrochloride extractant (r = 0.88, significant at the 0.01 probability level). Comparison of the amount of arsenic extracted by soil methods with bioavailable arsenic showed the following trend: ammonium oxalate, hydroxylamine hydrochloride > in vivo > phosphate, acetate > water. The amount of arsenic dissolved in the stomach (potentially bioavailable) is between surficially adsorbed (extracted by phosphate or acetate) and surficially adsorbed + nonsurficial forms in Fe and Mn oxides (extracted by hydroxylamine hydrochloride or ammonium oxalate). Soil extraction methods that dissolve some of the amorphous Fe, such as hydroxylamine hydrochloride, can be designed to provide closer estimates of bioavailable arsenic.

Skeletal stability after mandibular setback surgery.

Postsurgical stability of mandibular setback to correct class III malocclusion was studied in 14 patients who underwent sagittal split osteotomy with circummandibular wiring and elastic IMF. Lateral cephalograms were analyzed before surgery, immediately after surgery, and at least 6 months after surgery, using three linear measurements. A simple regression analysis was used to determine the relationship between skeletal relapse and the magnitude of mandibular setback. Methods for preventing relapse are discussed.

[Cardiovascular effects of ketamine anesthesia in rats treated with enalapril and propranolol]. / Efectos cardiocirculatorios de la anestesia con ketamina en ratas tratadas con enalapril y propranolol.

It is well-known that ketamine (Kt) anaesthesia produces a rise in blood pressure and heart rate in man. These cardiostimulatory effects were adscribed to several factors such as: a) increased sympathetic nervous system activity by direct stimulation of central nervous structures, b) increased catecholamine release from the peripheral sympathetic system, c) high plasmatic renin levels. However, the quantitative participation of these mechanisms in the cardiovascular effects of this anaesthetic agent is unknown. While some authors have shown a major rise in serum renin activity in experimental anaesthesia, others have been unable to confirm these results. The present study was undertaken to assess if the cardiostimulatory effects of Kt anaesthesia were due to an activation of renin-angiotensin system or to increased sympathetic activity. In consequence we used rats treated with enalapril (an angiotensin-converting enzyme inhibitor) or propranolol prior to anaesthetic procedures. Thirty male Wistar and six spontaneously hypertensive rats (SHR) weighing 240-300 g were used in all the experiments. The rats were randomly grouped into six groups. I- Non-anaesthetized rats, II- Anaesthetized rats (trained in the experimental procedures), III- Anaesthetized rats (without training), IV- Anaesthetized rats previously treated with enalapril, V- Anaesthetized rats pretreated with propranolol, VI- SHR treated with enalapril. The rats of groups IV and VI received enalapril p.o. for three weeks (25 mg/Kg body wt). The animals of group V were submitted to acute beta-adrenergic blockade. Propranolol dose: 10 mg/Kg body wt, was given i.p. 15 min before Kt anaesthesia. Blood pressure and heart rate were measured with a sphygmomanometer and photoelectric sensors and recorded.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood sugar concentrations during ketamine or pentobarbitone anesthesia in rats with or without alpha and beta adrenergic blockade.

Plasma glucose concentrations were measured in: 1) conscious and anesthetized rats during an iv glucose tolerance test (IVGTT) and 2) conscious and anaesthetized phentolamine/propranolol blocked rats during an IVGTT. Anesthesia was induced with ketamine (120 mg.kg-1) or pentobarbitone (60 mg.kg-1) ip at -30 min of the beginning of the IVGTT, which was followed by 2 injections of the anesthetic agents at intervals of 30 min. Propranolol (2 mg.kg-1) was given ip at -25 and -5 min. An iv infusion of phentolamine (0.015 mg.min-1) was started at -20 min and continued up to the end of the experiment. During the IVGTT, the anesthetized rats showed a moderate hyperglycemic response to glucose load compared to conscious animals (ketamine: p < 0.01 at 5 min; and p < 0.05 at 10-20 min; pentobarbitone: p < 0.05 at 5-20 min). The hyperglycemic response to glucose administration in the conscious rats was not affected by adrenergic blockade (p > 0.05). While in ketamine anesthetized rats the increased glucose response was abolished by adrenergic blockade (p < 0.05 at 5-10 min), this effect was not seen in pentobarbitone anesthetized animals. These results suggest the existence of an inhibitory tone on insulin secretion and a glycogenolytic response in ketamine anesthetized rats, probably mediated by adrenergic inervation of the pancreas and liver and by circulating catecholamines secreted from the adrenal medulla.

[Effects of beta-adrenergic blocking with propranolol on the mechanisms of glucose regulation in the dog]. / Efectos del bloqueo beta-adrenérgico con propranolol sobre los mecanismos de regulación de la glucemia en el perro.

Propranolol (P) administration is known to cause hypoglycemia in insulin-dependent diabetic patients. The mechanisms whereby this response is produced remain controversial. Some authors postulate an inhibition in the beta-adrenergic action of catecholamines, responsible for hepatic glycogenolysis, while others indicate that these hormones are not so important in the regulation of blood sugar (BS) level. The present studies were undertaken to assess the mechanism whereby hypoglycemia is developed in the dog, with or without beta-adrenergic blockade. Unanesthetized male mongrel dogs were used, weighing 10-20 kg body wt., fed on dog chow pellets and water ad libitum up to 18-22 hours before the test performances. The dogs were randomly grouped into two groups, A and B in which the effect of P on several hormonal and metabolic responses basally and during insulin (I) test, were respectively studied. Group A was constituted by two subgroups of 6 animals each; the animals of one subgroup were beta-blocked, receiving P p.o. for 10 days (80 mg every 8 hours); the dogs of the remaining subgroup received only P excipient in the same way as the treated ones, for the same period. As P treatment was completed, blood samples were taken by venipuncture, in a peripheral vein, at 0 and 60 min. Some biological controls of beta-blockade, assessed at 0, 30 and 60 min, indicated that mean pulse rate (+/- SE) in the control dogs was 123 +/- 2, 128 +/- 2 and 128 +/- 3 beats/min while in the P treated ones was 106 +/- 2, 103 +/- 1 and 103 +/- 3 respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Biochemical and molecular characterization of the venom from the Cuban scorpion Rhopalurus junceus.

This communication describes the first general biochemical, molecular and functional characterization of the venom from the Cuban blue scorpion Rhopalurus junceus, which is often used as a natural product for anti-cancer therapy in Cuba. The soluble venom of this arachnid is not toxic to mice, injected intraperitoneally at doses up to 200 µg/20 g body weight, but it is deadly to insects at doses of 10 µg per animal. The venom causes typical alpha and beta-effects on Na+ channels, when assayed using patch-clamp techniques in neuroblastoma cells in vitro. It also affects K+ currents conducted by ERG (ether-a-go-go related gene) channels. The soluble venom was shown to display phospholipase, hyaluronidase and anti-microbial activities. High performance liquid chromatography of the soluble venom can separate at least 50 components, among which are peptides lethal to crickets. Four such peptides were isolated to homogeneity and their molecular masses and N-terminal amino acid sequence were determined. The major component (RjAa12f) was fully sequenced by Edman degradation. It contains 64 amino acid residues and four disulfide bridges, similar to other known scorpion toxins. A cDNA library prepared from the venomous glands of one scorpion allowed cloning 18 genes that code for peptides of the venom, including RjA12f and eleven other closely related genes. Sequence analyses and phylogenetic reconstruction of the amino acid sequences deduced from the cloned genes showed that this scorpion contains sodium channel like toxin sequences clearly segregated into two monophyletic clusters. Considering the complex set of effects on Na+ currents verified here, this venom certainly warrant further investigation.