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.

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

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.

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.

Enzymatic activities in brains of diabetic rats treated with vanadyl sulphate and sodium tungstate.

The hypothesis of the present study was that diabetes mellitus might affect brain metabolism. Streptozotocin (STZ)-induced diabetic rats, treated with vanadyl sulphate (V) and sodium tungstate (T) were employed to observe the aspartate aminotransferase (AST), alanine aminotransferase (ALT) and creatine kinase (CK) activities in brain homogenates. Significant increases in AST, ALT and CK activities were found in diabetic brain homogenates against controls, suggesting increments of transamination in brain and/or increases in cell membrane permeability to these enzymes. The increase in brain CK possibly expresses alterations in energy production. The decrease in CK activity caused by V and T treatment in diabetic rats suggests that both agents tend to normalize energy consumption. It is also possible that V and T-induced hypoglycemic effects cause metabolic alterations in brain.

Decreased oxidative stress in prehepatic portal hypertensive rat livers following the induction of diabetes.

1. Oxidative stress (OS) is a biological entity indicated as being responsible for several pathologies, including diabetes. Diabetes can also be associated with human cirrhosis. Portal hypertension (PH), a major syndrome in cirrhosis, produces hyperdynamic splanchnic circulation and hyperaemia. The present study was designed to investigate the occurrence of OS in prehepatic PH rat livers following the induction of diabetes. 2. Five groups of rats were used: control, sham operated, chronic diabetes (induced with a single dose of streptozotocin at 60 mg/kg, i.p.), prehepatic PH and chronic diabetic plus prehepatic PH. The occurrence of OS was determined in liver homogenates by measuring hydroperoxide-initiated chemiluminescence and the activity of anti-oxidant enzymes (superoxide dismutase, catalase and glutathione peroxidase). 3. Prehepatic PH produced a significant increase in hydroperoxide-initiated chemiluminescence in the liver compared with control and sham-operated rats, whereas the liver in chronic diabetic rats showed no difference. However, chemiluminescence values decreased almost by 50% in the chronic diabetic plus prehepatic PH group. Concomitantly, the activities of the anti-oxidant enzymes in chronic diabetes, prehepatic PH and chronic diabetic plus prehepatic PH groups were decreased (P < 0.05 vs control and sham-operated groups). 4. Livers from the chronic diabetic group did not show any evidence of the occurrence of OS, whereas the prehepatic PH group showed the occurrence of OS. The association of PH and chronic diabetes resulted in a significant decrease in the occurrence of OS, which could be explained by an anti-oxidant response to an OS.

A type XI collagen mutation leads to increased degradation of type II collagen in articular cartilage.

OBJECTIVE: To determine in articular cartilage whether degraded type II collagen is more abundant in Col11a1 mutant cho/+ than in age-matched +/+ mice and whether collagen degradation occurs in a generalized or localized fashion. DESIGN: Knee joints from cho/+ and +/+ mice at 6, 9, 12 and 15 months of age were dissected, fixed, cryosectioned, and stained with antibody COL2-3/4m against denatured type II collagen using a FITC-conjugated secondary antibody. Sections were viewed and photographed under a fluorescence microscope and areas of staining were quantified. RESULTS: Before 12 months of age, little degraded collagen staining was detectable in +/+ or cho/+ mice. By 15 months, however, cho/+ mice showed significantly more degraded type II collagen than age-matched controls. Degraded collagen staining was localized at the articular surface, not distributed generally throughout the articular cartilage. CONCLUSIONS: The results suggest a model in which cumulative biomechanical stresses trigger increased collagen synthesis and degradation in both +/+ and cho/+ mice at around 12 months of age. Cho/+ mice, however, are less able to synthesize and assemble normal replacement collagen fibrils because of the Col11a1 mutation. Degradation is further activated, resulting in the accumulation of degraded type II collagen in the articular cartilage extracellular matrix. Similar mutations that do not overtly affect skeletal development may likewise predispose humans to increased collagen degradation and resultant osteoarthritis.

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.

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.

Growth of skeletal components in the young squirrel monkey (Saimiri sciureus boliviensis): a longitudinal experiment.

A functional skeletal criterion, as an extension of the van der Klaauw's cranial theory, was adopted in the present study. The null hypothesis tested was: "The major skeletal components of the platyrrhine body grow linearly, regardless of their functional dependence to different demands." The acceptance of the hypothesis will imply that all Saimiri skeletal growth may be satisfactorily explained by independent variables in a single equation. The rejection will suggest that such skeletal growth patterns have to be explained by variables in several different equations, and perhaps these equations may vary with the effect of sex and undernutrition. Control and undernourished squirrel monkeys were radiographed monthly for 2 years; they were also measured; and their volumetric and morphometric neurocranial, facial, and pelvic indices were calculated. The curves that best described each of the 24-point sequences were obtained. Three main growth patterns were observed: 1) Simple linear (femur length for all groups, and pelvic index for control and undernourished females), for which the simple regression equation explained more than 95% of the variation; 2) Complex linear (pelvic index for control and undernourished males, and neurocranial and facial indices for all of the groups), for which more than 95% of the variation was explained by one of the four four-function type equations; and 3) Noncorrelated with age (neurofacial index for undernourished males, and pelviofemoral index for control females and undernourished males and females), which showed nonsignificant correlations with respect to age. The food intake and the oscillations of the environmental temperature might help to explain the undulating growth trajectory observed in the complex linear components.

Características antropometricas del futbolista adolescente de elite / Anthropometric characteristics of elite adolescent soccer players

El objetivo de este trabajo consiste en estudiar antropométricamente a los futbolistas adolescentes de élite, comparar los resultados con los obtenidos en la población general de su edad y con los obtenidos de futbolistas profesionales en la bibliografía consultada, comprobar si existe un patrón antropométrico determinado para la práctica del fútbol desde la adolescencia y diferente al que presentan los adolescentes de la misma edad que no practican el fútbol a nivel competitivo. Se estudiaron 29 futbolistas, el total de los integrantes de la selección española sub-15 (nacidos en el año 1982) que participaron en diferentes competiciones internacionales durante el año 1998. A todos se les realizaron las siguientes mediciones antropométricas: talla, peso, seis pliegues cutáneos (tríceps, subescapular, suprailíaco, abdominal, muslo anterior, medial de la pierna); tres diámetros (biestiloideo, biepicondileo y bicondileo) y dos perímetros (bíceps contraído y pierna máxima), para obtener la composición corporal y el somatotipo. Se estableció un grupo de control de 100 adolescentes de la misma edad a los que se les realizaron las mismas mediciones antropométricas. El estudio estadístico se ha realizado mediante la Anova para variables cuantitativas y el test de la Chi cuadrado para variables cualitativas. Los adolescentes que practican el fútbol a nivel competitivo presentan la misma composición corporal y el mismo somatotipo que los futbolistas profesionales, sin encontrarse diferencias en los porcentajes graso, muscular y óseo. No obstante, hemos constatado diferencias significativas en la composición corporal con respecto a la población general de su edad, que no practican el fútbol a nivel competitivo. Los futbolistas adolescentes de élite presentan un menor porcentaje de grasa y un mayor porcentaje muscular que la población general de su edad. El somatotipo de los futbolistas estudiados es ectomesomorfo, mientras que el de la población general de su edad es endomesomorfo pero sin diferencias estadísticamente significativas. Los porteros a su vez presentan una altura y un peso significativamente superior al de los jugadores de campo (AU)

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 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 gonadal hormones on sexual dimorphism in malnutrition substrates]. / Efecto de las hormonas gonadales sobre el dimorfismo sexual en substrato de desnutrición.

The environmental effect on growth and sexual dimorphism is mediated by endocrinological dysfunctions. It was shown that malnutrition acts on the hypotalamus-pituitary-glandular axis. An experiment was made in Wistar rats to determine the effect of some gonadic hormones on the functional components of the skull to which sex dimorphism was alterated by a postnatal undernutrition. The effects of these hormones in restoring sexual cranial dimorphism was tested. Four treatments were applied: control, with food intake ad-libitum; undernutrition (50% of the control food intake); undernutrition plus periodic injections of testosterone and estradiol to males and females, respectively and sham-operated animals, which were injected with oil vehicle only. A radiological longitudinal study was performed between 20 and 80 days of postnatal age. The length width and height of the neural and facial components were measured on each radiograph. Data were processed by ANOVA and Mann-Whitney statistical tests were performed by means of the SYSTAT 7.0 statistical package. Results showed that gonadic hormones restored the sexual cranial dimorphism by stimulating (testosterone) or suppressing (estradiol) the growth of the cranial components.

The effect of segmental bronchoprovocation with allergen on airway lymphocyte function.

We hypothesized that allergen-induced airway eosinophilia is linked to activation or recruitment of T cells in the airway and generation of interleukin-5 (IL-5). To evaluate this hypothesis, we performed bronchoscopy with segmental antigen bronchoprovocation in 12 atopic subjects. Bronchoalveolar lavage (BAL) was done 5 min and 48 h after challenge with saline or antigen. Airway cells were isolated and then stimulated ex vivo with a T-cell mitogen, phytohemagglutinin (PHA), and cytokine release was determined. Cells retrieved from the saline-challenged segment secreted principally interferon-gamma (IFN-gamma) and IL-2. In contrast, cells obtained 48 h after allergen challenge secreted high levels of IL-5 and small but increased amounts of IL-4, IL-10, and granulocyte-macrophage colony-stimulating factor (GM-CSF). Although CD4+ T cells were a major source of IL-5, there were no significant changes in the relative proportion of CD4+ cells in response to bronchoprovocation. Additionally, ex vivo secretion of IL-5 by airway cells correlated closely with amounts of IL-5 and eosinophils present in the bronchoalveolar lavage fluid (BALF). These observations suggest that following exposure to allergen, airway T cells are functionally but not phenotypically different from resident airway T cells, and that T cells within the airway contribute to eosinophilic airway inflammation through the secretion of IL-5.

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.

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.

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.

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.