Patellar instability following experimental medial patellar desmotomy in horses.

A controlled study was designed in order to evaluate the effects of medial patellar desmotomy (MPD), combined with exercise restriction, on clinically and radiographically normal femoropatellar joints, and to identify the patellar instability by radiographic examination. MPD was performed on the right hind limb and the horses were rested for 120 days. Both hind limbs were radiographed before surgery and at 15, 30, 60, 90, and 120 days after MPD, obtaining lateromedial, flexed lateromedial, caudocranial and cranioproximal-craniodistal (skyline) views. The femorotibial and femoropatellar angles were assessed on the lateromedial views, and the distance between the medial and lateral cortex of the femur, and the distance between the medial cortex of the femur and the lateral border of the patella were evaluated in the caudocranial views. An increase in the angle between the proximal articular surface of the patella and the cranial distal surface of the femur along with enthesophyte formation and lateral deviation of the patella were found on the radiographs of the right stifles after MPD. Therefore, MPD leads to patellar instability, which can be demonstrated by the radiographic changes. The 120 days rest did not prevent the lesions caused by postsurgical patellar instability.

Detection of protamine 2 in bovine spermatozoa and testicles.

BACKGROUND: Sperm DNA integrity is crucial for transmission of genetic information to future generations and DNA damage can occur during chromatin packaging. Chromatin packaging involves the replacement of somatic nucleosomal histones by nuclear proteins called protamines. Protamine 1 (PRM1) is transcribed and translated in spermatids of all mammals; however, protamine 2 (PRM2) is transcribed in low levels in spermatids and it is not yet described in bull mature spermatozoa. OBJECTIVES: The aim of this study was to assess gene and protein expression of PRM2 and corroborate gene and protein expression of PRM1 in bull spermatozoa and testis. MATERIALS AND METHODS: For this purpose, absolute q-RT-PCR was performed to calculate the number of copies of PRM1 and PRM2 mRNAs in bovine epididymal spermatozoa and testicular tissue. Western blot and mass spectrometry were performed to identify PRM1 and PRM2 in samples of bovine epididymal spermatozoa. Samples of bovine testicular tissue were collected to identify PRM1 and PRM2 by immunohistochemistry. RESULTS: We evaluated that the number of PRM1 mRNA copies was about hundred times higher than PRM2 mRNA copies in sperm and testicular samples (p < 0.0001). In addition, we estimated the PRM1: PRM2 ratio based on mRNA number of copies. In spermatozoa, the ratio was 1: 0.014, and in testicle, the ratio was 1: 0.009. We also evaluated the immunolocalization for PRM1 and PRM2 in bovine testis, and both proteins were detected in spermatids. Western blot and mass spectrometry in bovine epididymal spermatozoa confirmed these results. CONCLUSION: Our work identifies, for the first time, PRM2 in bovine epididymal spermatozoa and in testis. Further studies are still needed to understand the role of PRM2 on the chromatin of the spermatozoa and to verify how possible changes in PRM2 levels may influence the bull fertility.

Effect of quinine administration on Purkinje cells in the cerebellar cortex of adult Wistar rats.

OBJECTIVE: The effect of quinine commonly used for the treatment of Chloroquine resistant malaria and cerebral malaria on the population and transverse diameters of Purkinje cells in the cerebellar cortex was investigated. METHODS: Twenty-seven adult male wistar rats weighing between 150 g and 190 g were separated into three groups, each containing nine rats. The rats in group I were injected intramuscularly with equivalent volume of physiological saline, while group II rats were injected intramuscularly with an initial 20 mg/kg body weight dose of quinine followed by a 10 mg/kg body weight dose given 8 hourly for 7 days. The group III rats received the same treatment as group II, but were subjected to a withdrawal period of one week. The cerebellum of each rat was removed and fixed in 10% formol saline for routine histological procedures. RESULTS: The Purkinje cell population reduced significantly (P < 0.05) from the mean value of 363 +/- 5.2 cells/mm2 in group I to a mean value of 239 +/- 9.5 cells/mm2 in group II and 220 +/- 6.6 cells/mm2 in group III rats. The transverse diameters of the Purkinje cells also reduced significantly (p < 0.05) from the mean value of 1.20 +/- 0.02 microm in the group I to a mean value of 1.09 +/- 0.1 microm in group II and 0.75 +/- 0.03 microm in group III. CONCLUSION: The observed decrease in population and diameters of Purkinje cells in the treatment groups may impair cerebellar functions since they are the principal neurons of the cerebellum.

Resistance of mice to Leptospira infection and correlation with chemokine response.

Leptospirosis is globally widespread neglected disease, affecting most mammalian species. Clinical signs can be confused with other diseases which make the diagnosis and treatment difficult. Chemokines and cytokines are known for their role in the inflammatory and immune response to infections. The profile determination of chemokines' expressions in the course of infection may elucidate the defense mechanisms of the host and support the search for effective treatment strategies. We investigated the mechanisms of innate immunity through the comparison of chemokines induced during infection with L. interrogans in mice with different levels of susceptibility. We used lung and spleen tissues samples of mice from C3H/HeJ, C3H/HePas and Balb/c, respectively sensitive, intermediate susceptibility and resistant to the pathogen. The inoculation of L. interrogans in C3H/HeJ mice led a comparatively smaller change in chemokines expression in both spleen and lung tissues. In samples from spleens and lungs of C3H/HePas and Balb/c the higher increases occurred on CXCL9, CXCL16, CXCL5, CCL8 and CCL5 in Balb/c. Given the same genetic background, the differences in the responses of C3H/HePas compared to C3H/HeJ mice strongly suggest the role of chemokines for the survival of parental strain. Therefore, the greatest increase in CXC chemokines appears to be efficient to induce migration of cells to the secondary lymphoid organs and affected tissues, which is important to control infection. Overall, CXC chemokines are important for the activation and attraction of T cell and may influence the course and control of the infection in resistant Balb/c mice.

Propolis: Effect of different concentrations, extracts and intake period on seric biochemical variables.

Propolis is a resinous substance produced by honeybees that possesses many biological activities, such as antitumor, antioxidant, antimicrobial, anti-inflammatory, and immunomodulatory, among others. The purpose of the present study was to investigate the biochemical profile of propolis-treated rats to observe whether propolis might lead to side effects after administration. Three different treatments were analyzed: (1) rats were treated with different concentrations of propolis (1, 3 and 6 mg/kg/day) during 30 days; (2) rats were treated with 1 mg/kg/day of ethanolic or water extracts of propolis (EEP, WEP) during 30 days; (3) rats were treated with 1 mg/kg/day of ethanolic extract of propolis during 90 and 150 days. Our results demonstrated no alterations in the seric levels of cholesterol, HDL-cholesterol, total lipids, triglycerides and in the specific activity of aminotransferases (AST) and lactic dehydrogenase (LDH) of propolis-treated groups when compared to controls. On the basis of our findings, since propolis does not induce any significant change in seric parameters, it is claimed that long-term administration of propolis might not have any cardiac injury.

DNA damage and lethal effects of hydrogen peroxide and menadione in Chinese hamster cells: distinct mechanisms are involved.

Menadione (Md)-resistant variants of V79 Chinese hamster cells were derived by culturing cells in progressively higher concentrations of this drug. Along with Md resistance these cells acquired cross-resistance to H2O2, which was retained when cells were cultured back in the absence of Md for 18 cell passages. This indicates that some stable alteration is responsible for the modification and may suggest that the toxicity of Md is mediated by oxygen activation. In agreement with the latter a 2.8-fold increase in catalase activity and a 1.5-fold increase in glutathione content were observed in Md-resistant cells as compared to parental cells, whereas superoxide dismutase and glutathione peroxidase remained unaltered. The use of inhibitors of Fenton reaction, inhibitors of enzymatic and nonenzymatic lipid peroxidation and OH radical scavengers, indicated that both DNA damage and cytotoxic effects of H2O2 and Md are mediated by OH radical, without intervention of lipid peroxides. However whereas the catalysis by iron was required for toxicity of extracellular H2O2, it was not involved in Md-induced toxicity. Possible explanations for this difference have been considered, one of them assuming that an excess of the semiquinone form of Md in the cell might replace iron II as a H2O2 reductant, producing OH radical by an organic Fenton reaction.

Role of antioxidants in protecting cellular DNA from damage by oxidative stress.

We have previously derived 2 V79 clones resistant to menadione (Md1 cells) and cadmium (Cd1 cells), respectively. They both were shown to be cross-resistant to hydrogen peroxide. There was a modification in the antioxidant repertoire in these cells as compared to the parental cells. Md1 presented an increase in catalase and glutathione peroxidase activities whereas Cd1 cells exhibited an increase in metallothionein and glutathione contents. The susceptibility of the DNA of these cells to the damaging effect of H2O2 was tested using the DNA precipitation assay. Both Md1 and Cd1 DNAs were more resistant to the peroxide action. In the case of Md1 cells it seems clear that the extra resistance is provided by the increase in the two H2O2 scavenger enzymes, catalase and glutathione peroxidase. In the case of Cd1 cells the activities of these enzymes as well as of superoxide dismutases (Cu/Zn and Mn) are unaltered as compared to the parental cells. The facts that parental cells exposed to 100 microM Zn2+ in the medium exhibit an increase in metallothionein but not in glutathione and that these cells become more resistant to the DNA-damaging effect of H2O2 suggest that this protein might play a protective role in vivo against the OH radical attack on DNA.

Iron-mediated induction of sister-chromatid exchanges by hydrogen peroxide and superoxide anion.

When Chinese hamster fibroblasts were exposed to hydrogen peroxide or to a system consisting of xanthine oxidase and hypoxanthine, which generates superoxide anion plus hydrogen peroxide, sister-chromatid exchanges (SCEs) were formed in a dose-dependent manner. When the iron-complexing agent o-phenanthroline was present in the medium, however, the production of these SCEs was completely inhibited. This fact indicates that the Fenton reaction: Fe2+ + H2O2----OH0 + OH- + Fe3+ is responsible for the production of SCEs. When O2- and H2O2 were generated inside the cell by incubation with menadione, the production of SCE was prevented by co-incubation with copper diisopropylsalicylate, a superoxide dismutase mimetic agent. The most likely role of O2- is as a reducing agent of Fe3+: O2- + Fe3+----Fe2+ + O2, so that the sum of this and the Fenton reaction, i.e., the iron-catalyzed Haber-Weiss reaction, provides an explanation for the active oxygen species-induced SCE: H2O2 + O2(-)----OH- + OH0 + O2. According to this view, the OH radical thus produced is the agent which ultimately causes SCE. These results are discussed in comparison with other mechanisms previously proposed for induction of SCE by active oxygen species.

Genome features of Leptospira interrogans serovar Copenhageni.

We report novel features of the genome sequence of Leptospira interrogans serovar Copenhageni, a highly invasive spirochete. Leptospira species colonize a significant proportion of rodent populations worldwide and produce life-threatening infections in mammals. Genomic sequence analysis reveals the presence of a competent transport system with 13 families of genes encoding for major transporters including a three-member component efflux system compatible with the long-term survival of this organism. The leptospiral genome contains a broad array of genes encoding regulatory system, signal transduction and methyl-accepting chemotaxis proteins, reflecting the organism's ability to respond to diverse environmental stimuli. The identification of a complete set of genes encoding the enzymes for the cobalamin biosynthetic pathway and the novel coding genes related to lipopolysaccharide biosynthesis should bring new light to the study of Leptospira physiology. Genes related to toxins, lipoproteins and several surface-exposed proteins may facilitate a better understanding of the Leptospira pathogenesis and may serve as potential candidates for vaccine.

Efficacy of the nocturnal bite plate in the control of bruxism for 3 to 5 year old children.

Bruxism occurs in nearly 60% of children between 3 and 5 years, with important repercussions to the different components of the stomatognathic system. Nevertheless, there is little information in the literature about this topic. The aim of this study was to compare two groups of children with bruxism. One group was not submitted to treatment, serving as a control. To the other group, nocturnal bite plate was made. Cast models were made for both groups, to evaluate the progression of wear facets, during 8 months. The results are as follows: The 4 children of the control group displayed increased wear facets during the study period. On the other hand, of the 5 children that used nocturnal bite plate, showed no increase of wear facets, even after the removal of the device. From this study, we can conclude that the use of nocturnal bite plate is efficient against bruxism in 3- to 5-year-old children.

[Evaluation of an instrument for the classification of patients in four levels of dependency on nursing care]. / Validação de um instrumento que classifica os pacientes em quatro graus de dependência do cuidado de enfermagem.

This study presents the process of validation of a tool that classifies patients in four levels of dependence to the nursing care delivered at a University Hospital. The research gave to participants an opportunity to analyse patients' needs, showing the instrument as an efficient tool for nursing practice.

[The effect of sugar on the process of cicatrization of infected surgical incisions]. / Influência do açúcar no processo de cicatrização de incisões cirúrgicas infectadas.

This is an experimental research based on microbiological analysis. Our aim was to evaluate the influence of sugar on the healing process of infected surgical wounds in 25 patients. On the dehiscences, there have been identified gram positive and gram negative bacteria, and fungi as well. Every patient was administered systemic antibiotics and had the wounds treated locally with crystal sugar three times a day. Statistics showed, by Person's correlation, that sugar did not influence on the healing process of infected surgical wounds in undernourished, overweight and elderly individuals.

[Teacher-student communication across the Tizadora pedagogical problem]. / Communicaçäo professor-aluno através da pedagogia problematizadora.

Report of experience in the use of a social-cultural approach during the development of a work done by graduate students of Ribeiräo Preto School of Nursing-USP. As a form of reference for the didactic strategy, it was used the scheme of arch proposed by Charles Maguerez and presented by BORDENAVE, in an attempt to systematize the communication teacher-student talking about "Aspects related to the Undergraduate Teaching Problems".

Concentração sérica de progesterona, pH da vagina e morfometria corpórea de cervas gestantes (Cervus unicolor) em cativeiro / Serum concentration of progesterone, pH of the vagina and body morphometryof pregnant deer (Cervus unicolor)in captivity

The aim was to study pregnant cervus in captivity, to obtain body morphometric data, serum progesterone concentrations, and pH of the vagina. Females of cervus (Cervus unicolor), (n=8) between 2 and 3 years old were used in November during breeding season. After sedation, in one collection, the following was measured: body weight 54.50 ± 18.70kg, body length 1.21 ± 0.16m, height at withers 0.75 ± 0.08m, thoracic perimeter 0.84 ± 0.12m, and body mass index 97.32 ± 10.50kg / m2. After sedation, blood samples were collected to measure progesterone concentration by radioimmunoassay and the use of an indicator tape to obtain the pH of the vagina was performed eight times at four day intervals in the eight females, in a total of 64 samples for each exam. Data were analyzed, and significance was at 5%. There were no differences (P> 0.05) between measurements for serum progesterone concentrations and pH of the vagina. The correlations between body weight, progesterone, pH, and body mass index were not significant (P> 0.05). There was no significant oscillation of progesterone concentration and pH of the vagina in the pregnancy period studied.

Concentração sérica de progesterona, pH da vagina e morfometria corpórea de cervas gestantes (Cervus unicolor) em cativeiro / Serum concentration of progesterone, pH of the vagina and body morphometryof pregnant deer (Cervus unicolor)in captivity

The aim was to study pregnant cervus in captivity, to obtain body morphometric data, serum progesterone concentrations, and pH of the vagina. Females of cervus (Cervus unicolor), (n=8) between 2 and 3 years old were used in November during breeding season. After sedation, in one collection, the following was measured: body weight 54.50 ± 18.70kg, body length 1.21 ± 0.16m, height at withers 0.75 ± 0.08m, thoracic perimeter 0.84 ± 0.12m, and body mass index 97.32 ± 10.50kg / m2. After sedation, blood samples were collected to measure progesterone concentration by radioimmunoassay and the use of an indicator tape to obtain the pH of the vagina was performed eight times at four day intervals in the eight females, in a total of 64 samples for each exam. Data were analyzed, and significance was at 5%. There were no differences (P> 0.05) between measurements for serum progesterone concentrations and pH of the vagina. The correlations between body weight, progesterone, pH, and body mass index were not significant (P> 0.05). There was no significant oscillation of progesterone concentration and pH of the vagina in the pregnancy period studied.(AU)

Morfometria corpórea, características do sêmen, proteínas seminais e testosterona em cervos Cervus unicolor, em cativeiro / Body morphometry, semen characteristics, seminal proteins and testosterone in sambar deer (Cervus unicolor) in captivity

Objetivou-se estudar a morfometria corpórea, as características do sêmen, o perfil proteico do plasma seminal em SDS-PAGE e a concentração sérica de testosterona em cervos-sambar (Cervus unicolor), criados em cativeiro, na estação reprodutiva da primavera. Quatro machos com idades entre 12 e 36 meses foram avaliados em quatro momentos, com intervalos de sete dias, com peso corpóreo (60,5 a 89,0kg), índice de massa corporal (93,07kg/m2 a 126,56kg/m2), volume do ejaculado (0,50±0,35mL a 0,75±0,28mL), motilidade espermática (87,75±4,78% a 90,00±7,07%), defeitos totais (17,25±5,81% a 47,72±17,55%), testosterona sérica (6,43±4,33ng/dL a 166,00±64,48ng/dL) e proteínas do plasma seminal com bandas entre 7,6 e 142kDa. As características dos ejaculados não diferiram (P>0,05) entre as três primeiras colheitas. Houve diferença (P<0,05) para os defeitos espermáticos com elevação na quarta colheita. No plasma seminal de cada cervo, foram identificadas de 16 a 27 bandas de proteínas entre 7,6 e 142kDa. Conclui-se que a qualidade espermática foi satisfatória na primavera. O estresse das contenções sucessivas causou queda da qualidade espermática. A idade influi na concentração sérica de testosterona, a qual foi maior nos cervos aos 36 meses...

The aim of this work was to study the body morphometry, semen characteristics, seminal plasma protein profile in SDS-PAGE and serum testosterone concentration in Sambar Deer (Cervus unicolor), in captivity in the breeding season (spring). Four males aged between 12 and 36 months were assessed in four moments with intervals of seven days with body weight (60.5 to 89.0kg), body mass index (93.07 to 126.56kg/m2), ejaculate volume (0.50±0.35mL to 0.75±0.28mL), sperm motility (87.75±4.78% to 90.00±7.07% ), total defects (17.25±5.81% to 47.72±17.55%), serum testosterone (6.43±4.33 ng/dL to 166.00±64.48ng/dL) and seminal plasma proteins with bands between 7.6 and 142 kDa. The characteristics of ejaculates did not differ (P>0.05) among ejaculates (1st, 2nd and 3rd). There were differences (P<0.05) for sperm defects elevation on the fourth ejaculate. In seminal plasma 16 to 27 protein bands between 7.6 and 142 kDa were identified. In conclusion, sperm quality was satisfactory in the spring and the stress of successive contentions decreased sperm quality. Also, there is influence of age upon serum testosterone concentration which was higher in deer at 36 months...

Cellular DNA damage by hydrogen peroxide is attenuated by hypotonicity.

Chinese hamster fibroblasts (line V79) withstand well exposure for 30 min to hypotonic medium, corresponding to 25% physiological phosphate-buffered saline (PBS). Under these conditions, the cells become resistant to two effects of H2O2: DNA damage and inhibition of cell clone formation. The normal sensitivity to the DNA-damaging action of H2O2 is restored if, after exposure to hypotonic PBS, the cells are incubated in isotonic cell-culture medium. However, restoration of sensitivity is not observed on incubation in isotonic PBS. The normal sensitivity to H2O2 is also restored if one of the following reducing agents is added to hypotonic PBS: ascorbate, NADH and NADPH, in this order of decreasing efficiency. The recovery of sensitivity to H2O2 by ascorbate is completely inhibited by 1,10-phenanthroline, indicating that ascorbate is mediating the reduction of Fe(III). The decrease in the sensitivity to the DNA-damaging action of H2O2 is not a peculiarity of hypotonic PBS, since it appears to be caused by hypo-osmolarity in general: it is also observed in culture medium of 25% the isotonic concentration, and in 0.07 M sucrose. One explanation for this phenomenon is that hypotonic stress leads to a depletion of reducing species, in particular ascorbate. Under these conditions Fe(II) tends to be oxidized to Fe(III) and the Fenton chemistry is mitigated. However, other possibilities are that hypotonicity brings about structural modifications in the chromatin, rendering it less accessible to H2O2, or that it attenuates the Ca(2+)-activation of endonuclease, induced by oxidative stress.

Oxidative stress induces activation of a cytosolic protein responsible for control of iron uptake.

A cytosolic protein, named iron-responsive element-binding protein (IRE-BP), is sensitive to cellular iron concentration. At low cytosolic iron level, IRE-BP is activated and binds to stem-loop untranslated regions (IRE regions) of transferrin and ferritin mRNAs, activating and inhibiting their translations, respectively. This concerted mechanism permits a fine control of iron homeostasis in the cell. The activity of IRE-BP can be measured by its binding to IRE regions, using a protein band-shift electrophoretic assay. Damage to cells by oxidative stress is known to be mediated by iron. We observed that IRE-BP is rapidly activated by exposure of V79 Chinese hamster ovary cells to H2O2. However, if cell extracts are exposed to H2O2 IRE-BP activation is not observed. Therefore, the activation is not a direct consequence of the H2O2 attack to IRE-BP. The in vivo IRE-BP-activation by H2O2 is not prevented by hydroxyl radical scavengers or by the iron chelator 1,10-phenanthroline, indicating that Fenton reaction is not involved in the process. In fact, simultaneous exposure of cells to H2O2 and 1,10-phenanthroline produces an even stronger activation than exposure to H2O2 alone. The interpretation of the mechanism of IRE-BP activation by oxidative stress is hampered by the fact that the mechanism of IRE-BP modulation by cytosolic iron has not been established. It has been recently shown that the iron-sulfur cluster in IRE-BP must be completely disassembled in order for activation to occur and that this is triggered by low iron in the cell. It is likely that IRE-BP senses Fe(II) and that its oxidation to Fe(III) by H2O2 or chelation by 1,10-phenanthroline set up a program for increasing iron uptake. The physiological consequences of this activation still has to be assessed.

Oxidative stress by menadione affects cellular copper and iron homeostasis.

Menadione produces DNA strand breaks (DNA sb) in cultured Chinese hamster fibroblasts which are, to a great extent, mediated by OH radical. A reasonable hypothesis is that H2O2, a product of menadione metabolism, reacts with nuclear iron and produces OH radical in situ. Consistent with that, 1,10-phenanthroline (PHEN) prevents menadione-induced DNA sb at low (< 200 microM) concentrations of the chelator. However, at higher PHEN concentrations, the effect is reversed and an enhancement of DNA sb is observed. The PHEN-induced enhancement of DNA sb becomes more evident at high (> 60 microM) menadione concentrations and is strongly prevented by neocuproine (NEO), an efficient copper chelator. However, NEO offers only a slight protection against DNA sb caused by menadione alone. The results are consistent with the following events: (i) the products of menadione metabolism causes copper ion release from some cellular compartment; (ii) in the presence of PHEN, a Cu(PHEN)2 complex is formed; (iii) the Cu(PHEN)2 complex is known to be very clastogenic, inducing DNA damage in a reducing environment. Evidence is also presented that menadione metabolism causes an increase in intracellular chelatable iron: in the presence of a constant 2,2'-dipyridyl concentration, the DNA sb produced by increasing concentrations of menadione become progressively less susceptible to inhibition by the chelator. Therefore the DNA damage originated from menadione metabolism seems to be caused by two conjugated and synergistic events, viz., the production of reactive oxygen species and the release of copper and iron from a cellular storage site into a 'free' form pool, capable of catalyzing DNA damaging reactions.

Effect of insulin on the size of skeletal muscle fibers of fetal rhesus monkey.

Increased body weight of insulin-treated fetuses is largely attributed to increased muscle mass. Skeletal muscle from fetal rhesus monkeys was analyzed for differences in the sizes of muscle fibers from monkeys treated in utero with high or low doses of insulin and compared to control (non-insulin-treated) animals. The results indicate no significant difference among the various groups studied and suggest that hyperplasia, not hypertrophy, of skeletal muscle fibers is responsible for the observed increase in muscle mass.