Synchrotron microtomography applied to the volumetric analysis of internal structures of Thoropa miliaris tadpoles.

Amphibians are models for studying applied ecological issues such as habitat loss, pollution, disease, and global climate change due to their sensitivity and vulnerability to changes in the environment. Developmental series of amphibians are informative about their biology, and X-ray based 3D reconstruction holds promise for quantifying morphological changes during growth-some with a direct impact on the possibility of an experimental investigation on several of the ecological topics listed above. However, 3D resolution and discrimination of their soft tissues have been difficult with traditional X-ray computed tomography, without time-consuming contrast staining. Tomographic data were initially performed (pre-processing and reconstruction) using the open-source software tool SYRMEP Tomo Project. Data processing and analysis of the reconstructed tomography volumes were conducted using the segmentation semi-automatic settings of the software Avizo Fire 8, which provide information about each investigated tissues, organs or bone elements. Hence, volumetric analyses were carried out to quantify the development of structures in different tadpole developmental stages. Our work shows that synchrotron X-ray microtomography using phase-contrast mode resolves the edges of the internal tissues (as well as overall tadpole morphology), facilitating the segmentation of the investigated tissues. Reconstruction algorithms and segmentation software played an important role in the qualitative and quantitative analysis of each target structure of the Thoropa miliaris tadpole at different stages of development, providing information on volume, shape and length. The use of the synchrotron X-ray microtomography setup of the SYRMEP beamline of Elettra Synchrotron, in phase-contrast mode, allows access to volumetric data for bone formation, eye development, nervous system and notochordal changes during the development (ontogeny) of tadpoles of a cycloramphid frog Thoropa miliaris. As key elements in the normal development of these and any other frog tadpole, the application of such a comparative ontogenetic study, may hold interest to researchers in experimental and environmental disciplines.

Parâmetros hemodinâmicos e ventilatórios em coelhos anestesiados com isoflurano, submetidos à ventilação controlada à pressão com ou sem PEEP / Hemodynamic and ventilatory parameters in rabbits anesthetized with isoflurane submitted to pressure controlled ventilation with or without PEEP

Foi comparada a ventilação controlada à pressão com ou sem pressão positiva expiratória final (PEEP), em coelhos, distribuídos em três grupos, denominados GP (grupo ventilação ciclada à pressão), GPP (grupo ventilação ciclada à pressão com PEEP) e GE (grupo ventilação espontânea - grupo controle). Os animais foram anestesiados com isoflurano, em circuito com reinalação de gases, durante duas horas. As médias de pressão arterial média (PAM) e pressão arterial sistólica (PAS) permaneceram discretamente abaixo dos valores normais em todos os grupos. Houve diminuição significativa da PAM e da PAS no grupo submetido à PEEP (GPP) ao longo do tempo. A pressão parcial de dióxido de carbono arterial (PaCO2) foi maior no GPP quando comparado aos outros grupos no último momento, gerando acidemia respiratória após uma hora de procedimento. A concentração de dióxido de carbono ao final da expiração (ETCO2) apresentou médias discretamente elevadas no grupo não tratado com PEEP (GP) e no grupo controle, enquanto o GPP apresentou maiores médias, possivelmente, relacionadas à diminuição do volume corrente neste grupo. Com base nesses resultados, foi possível concluir que a utilização da PEEP levou à acidemia, que se agravou ao longo do tempo anestésico. Ademais, a anestesia prolongada com isoflurano promove depressão cardiorrespiratória, independentemente do modo ventilatório empregado.(AU)

Pressure controlled ventilation with or without positive end-expiratory pressure (PEEP) was compared in rabbits, which were divided into three groups denominated GP (pressure cycled ventilation group), GPP (pressure cycled ventilation with PEEP group) and GE (spontaneous ventilation group - control group). The animals were anesthetized with isoflurane in a gas rebreathing circuit for two hours. The means of mean arterial pressure (MAP) and systolic blood pressure (SBP) remained slightly below normal values ​​in all groups. There was a significant decrease in MAP and SBP in the group submitted to PEEP (GPP) over time. The partial pressure of arterial carbon dioxide (PaCO2) was higher in GPP when compared to the other groups, inducing respiratory acidosis after one hour. The end-expired carbon dioxide concentration (ETCO2) presented slightly elevated means in the GP, while the GPP presented higher means, possibly related to the decrease in tidal volume in this group. Based on these results it was concluded that the use of PEEP led to acidemia that worsened over anesthetic time. In addition, prolonged isoflurane anesthesia promotes cardiorespiratory depression, regardless the ventilatory mode employed.(AU)

Hemodynamic variables in piglets anesthetized with isoflurane or propofol, kept under spontaneous ventilation and FIO2 of 0. 5 / Variáveis hemodinâmicas em suínos anestesiados com isoflurano ou propofol, mantidos sob ventilação espontânea e FIO2 de 0,5

This study aimed to evaluate comparatively the effects of propofol or isoflurane on hemodynamic variables in piglets that received inspired oxygen fraction (FIO2) of 0.5 under spontaneous ventilation. Therefore, sixteen piglets weighing 16±1.1kg, were randomly divided into two groups: GI (Isoflurane and FIO2 of 0.5) and GP (Propofol and FIO2 of 0.5). Heart rate (HR), systolic, diastolic and mean arterial pressure (SAP, DAP and MAP), central venous pressure (CVP), cardiac output (CO), mean pulmonary arterial pressure (mPAP) and mean capillary pulmonary pressure (mCPP) were assessed 40 minutes after anesthetic induction (T0), followed by 15 minutes intervals (from T15 to T60). The variables cardiac index (CI), stroke volume (SV), stroke index (SI), total peripheral resistance (TPR), total peripheral resistance index (TPRI), pulmonary vascular resistance (PVR), and pulmonary vascular resistance index (PVRI) were calculated. SAP and TPRI were significantly different between groups at T30 and T60 (P< 0.05) with higher GP values being recorded. There were no differences in the other variables, however, GP presented mean closer to normality on most of the analyzed variables. Therefore, we conclude that total intravenous anesthesia with propofol presented greater stability of the hemodynamic variables evaluated.(AU)

O objetivo deste estudo foi avaliar comparativamente os efeitos do propofol ou do isoflurano sobre as variáveis hemodinâmicas em leitões que receberam fração inspirada de oxigênio (FIO2) de 0,5 sob ventilação espontânea. Dezesseis leitões, pesando 16±1,1kg, foram divididos aleatoriamente em dois grupos: GI (isoflurano e FIO2 de 0,5) e GP (propofol e FIO2 de 0,5). A frequência cardíaca (FC), a pressão arterial sistólica, a diastólica e a média (PAS, PAD e PAM), a pressão venosa central (PVC), o débito cardíaco (DC),a pressão média da artéria pulmonar (PAPm) e a pressão média capilar pulmonar (PCPm) foram avaliados 40 minutos após a indução anestésica (T0), seguida por intervalos de 15 minutos (de T15 a T60). As variáveis índice cardíaco (IC), volume sistólico (VS), índice sistólico (SI), resistência periférica total (RPT), índice de resistência periférica total (IRPT), resistência vascular pulmonar (RVP) e índice de resistência vascular pulmonar (IRVP) foram calculadas. PAS e IRPT foram significativamente diferentes entre os grupos em T30 e T60 (P<0,05) com maiores valores de GP sendo registrados. Não houve diferenças nas demais variáveis, entretanto o GP apresentou médias próximas da normalidade na maioria das variáveis analisadas. Portanto, concluiu-se que a anestesia intravenosa total com propofol apresentou maior estabilidade das variáveis hemodinâmicas avaliadas.(AU)

Blood gas analysis in pigs submitted to different concentrations of nitrous oxide or oxygen, under different ventilatory modalities / Estudo hemogasométrico em suínos submetidos a diferentes concentrações de óxido nitroso ou oxigênio, sob diferentes modalidades ventilatórias

The effects of different concentrations of oxygen and nitrous oxide on blood gas parameters in pigs maintained under spontaneous or pressure-controlled ventilation, with or without positive end-expiratory pressure (PEEP), were compared. Forty-eight pigs were randomly divided into six groups, submitted to different concentrations of compressed air or N2O, associated with different fractions of inspired oxygen (FiO2). The group subject to 30% of compressed air (GA30) showed the closest proximity to the physiological range of partial pressure (PaO2) expected for the species. For oxygen saturation (SaO2), the values obtained were below the lower physiological limit in the group administered 30% N2O (GN30). Use of PEEP positively interfered in PaCO2 independent of FiO2, however, its effectiveness can be compromised when complemented by N2O-based anesthesia. For SaO2, only GN30 showed values lower than adequate for maintaining tissue oxygenation. The pH, base deficit and bicarbonate in arterial blood were influenced by FiO2 and N2O. In conclusion, the use of compressed air maintains blood gas parameters at their most stable, especially GA30 and PEEP, which seemed to positively influence the experimental groups, with some interference from FiO2 and N2O.(AU)

Compararam-se os efeitos de diferentes concentrações do óxido nitroso ou oxigênio sobre variáveis hemogasométricas, em suínos mantidos em ventilação espontânea ou controlada à pressão, associada ou não à pressão expiratória final positiva (PEEP). Foram utilizados 48 porcos, distribuídos em seis grupos. Administraram-se diferentes concentrações de ar comprimido ou N2O, associadas a diversas frações de oxigênio inspirado (FiO2). O grupo sujeito a 30% de ar comprimido (GA30) mostrou maior proximidade do intervalo fisiológico da pressão parcial de oxigênio (PaO2). Para a saturação de oxigênio (SaO2), observaram-se valores aquém do limite inferior fisiológico no grupo administrado com 30% de N2O (GN30). A utilização da PEEP é capaz de interferir positivamente na PaCO2, independentemente da FiO2, porém tem a efetividade comprometida quando há complemento da anestesia com o N2O. Para a SaO2, apenas o GN30 esboçou valores inferiores aos adequados para manutenção da oxigenação tecidual. O pH, o déficit base e o bicarbonato no sangue arterial foram influenciados pela FiO2 e pelo N2O. Concluiu-se que o uso do ar comprimido mantém os parâmetros hemogasométricos mais estáveis, com destaque para o GA30 e a PEEP, o que parece influenciar positivamente os grupos experimentais, mas com interferência da FiO2 e do N2O.(AU)

Acute effects of resistance training with local vibration.

The aim of this study was to verify the acute effects of the application of local vibration on upper limbs during resistance training on the number of maximum repetitions, metabolic and hormonal responses. 32 volunteers performed a maximum voluntary contraction test during a lat pulldown exercise. After the test, all volunteers underwent one conventional resistance training session and one resistance training session with local vibration. In both interventions, volunteers performed 4 sets with the highest possible number of repetitions of the lat pulldown exercise at 55% of maximum voluntary contraction. During the vibratory resistance training intervention, vibration was locally applied (20-Hz and 12-mm). During the conventional resistance training, volunteers performed the same procedures without vibration. Blood samples were taken at each experimental session before and 5 min after the end of each intervention. No significant differences were observed in number of maximum repetitions between the series of vibratory and conventional training. Serum testosterone, cortisol and lactate were significantly increased after 2 interventions. Vibratory resistance training induced greater increases in testosterone and lactate concentrations. No significant changes were found in creatine kinase, creatinine or urea concentration. These data indicate that local vibration increases the metabolic and anabolic response to the resistance training, without changing the training volume.

Chronic effects of different frequencies of local vibrations.

The aim of this study was to compare the chronic effects of different frequencies of mechanical vibrations, applied in the direction of the resultant muscle forces' vector addition, on the performance of the lower extremities. After performing the maximal voluntary contraction (MVC), squat jump (SJ), countermovement jump (CMJ), multiple vertical jumps and running speed tests, 55 male volunteers were distributed into 4 groups: an Isometric group, an 8-Hz group, a 26-Hz group and a Control group. After a 4-week training period, the same tests were performed. The training groups reached a significant increase of the MVC, but the increases of the 8-Hz (23.2%) and 26-Hz (22.2%) groups were higher than the Isometric group (12.1%). A significant increase was observed between SJ and CMJ values measured at the pre-test and the post-test stages in the 8-Hz (SJ=11.1%; CMJ=8.7%) and 26-Hz groups (SJ=9.6%; CMJ=7.5%). No differences were observed between 8-Hz and 26-Hz groups. The application of vibrations of 8 Hz and 26 Hz, directed to the resulting muscle forces, was able to increase the performance of the lower extremities. This kind of local vibration did not produce positive effects on multiple vertical jumps or running speed.

Linear-circular external skeletal fixation of intra-condylar humeral fractures with supracondylar comminution in four cats.

OBJECTIVES: Intra-condylar humeral fracture with supracondylar comminution in cats is rare, and the stabilisation for such fractures is challenging. The purpose of our study was to describe the use of a hybrid external skeletal fixator, and to report the complications and outcomes of this surgical technique. METHODS: A retrospective review was performed of clinical, radiographic and surgical records of all cats with intra-condylar humeral fractures and non-reconstructable supracondylar comminution stabilized by linear- circular external skeletal fixator in two institutions between January 2005 and March 2010. RESULTS: Four cats met the inclusion criteria of the study. All cases achieved fracture union and clinical outcome was considered excellent at the time of the final assessment (11 - 24 weeks). CLINICAL SIGNIFICANCE: This study demonstrates that a linear-circular fixator system can be used successfully in the management of intra-con dylar humeral fractures with non-reconstructable supracondylar comminution in cats.

The genetics of Parkinson's disease.

The effort to map the entire human genome has led recently to the important milestone publication in late 1999 of the complete sequence of chromosome 22. This has been facilitated by increasingly sophisticated tools for genetic analysis and the ensuing wealth of detailed genetic information. The quest for genetic factors contributing to Parkinson's disease and parkinsonian disorders has revealed a progressively complex picture implicating gene mutations in the rarer, autosomally inherited forms of Parkinson's disease and the interplay of genetic and/or environmental factors in the common sporadic forms of the disorder. These findings not only reiterate the complex genetic heterogeneity of Parkinson's disease but could also point towards common pathogenic mechanisms in Parkinson's disease and related neurodegenerative disorders.

Etiology and mortality of bacterial meningitis in northeastern Brazil.

Little is known of the current incidence and mortality of meningitis in developing nations, especially in Latin America. We reviewed all cases of meningitis in an isolation-fever hospital in Salvador, Brazil, for the decade 1973-1982. Of all admissions, 6,751 (27%) were for meningitis; 4,100 (61%) of these cases were of definite or probable bacterial etiology. Children younger than 15 years accounted for 79% of cases, and 45% of cases were in children under 2 years. The overall case fatality rate was 33%, with 50% of these deaths occurring within 48 hours of hospitalization. Neisseria meningitidis was the etiologic agent in 32% of the cases, with a case fatality rate of 14%. Epidemics caused by N. meningitidis group C, then group A, in 1974-1978 accounted for 60% of the cases. Streptococcus pneumoniae caused 17% of cases, with a case fatality rate of 59%. Haemophilus influenzae type b, the most common cause of nonepidemic meningitis, caused 23% of all cases, with a case fatality rate of 38%. Enterobacteriaceae were the etiology in only 3.6% of patients, but the case fatality rate was 86%. Cultures were negative in 18% of cases with purulent cerebrospinal fluid. A total of 84% of H. influenzae, 40% of S. pneumoniae, 78% of Enterobacteriaceae, and 15% of N. meningitidis cases occurred in children less than 2 years of age. Case fatality rates were highest in this group. Vaccines protective for this age group are urgently needed.

Comparison of ceftriaxone and ampicillin plus chloramphenicol for the therapy of acute bacterial meningitis.

Ceftriaxone, a new third-generation cephalosporin, appears to be promising for the therapy of acute bacterial meningitis. The 90% MBCs of ceftriaxone against 54 recent cerebrospinal fluid isolates of Streptococcus pneumoniae, Neisseria meningitidis, and Haemophilus influenzae were less than or equal to 0.06 to 0.25 micrograms/ml. We examined the efficacy and safety of ceftriaxone therapy of meningitis in Bahia, Brazil. The study was conducted in two phases; in phase A, ceftriaxone was coadministered with ampicillin. The mean cerebrospinal fluid concentrations of ceftriaxone 24 h after an intravenous dose of 80 mg/kg were 4.2 and 2.3 micrograms/ml on days 4 to 6 and 10 to 12 of therapy, respectively. These concentrations were 8- to more than 100-fold greater than the 90% MBCs against the relevant pathogens. In phase B, ceftriaxone (administered once daily at a dose of 80 mg/kg after an initial dose of 100 mg/kg) was compared with conventional dosages of ampicillin and chloramphenicol in a prospective randomized trial of 36 children and adults with meningitis. The groups were comparable based on clinical, laboratory, and etiological parameters. Ceftriaxone given once daily produced results equivalent to those obtained with ampicillin plus chloramphenicol, as judged by cure rate, case fatality ratio, resolution with sequelae, type and severity of sequelae, time to sterility of cerebrospinal fluid, and potentially drug-related adverse effects. The cerebrospinal fluid bactericidal titers obtained 16 to 24 h after ceftriaxone dosing were usually 1:512 to greater than 1:2,048 even late in the treatment course, compared with values of 1:8 to 1:32 in patients receiving ampicillin plus chloramphenicol. Ceftriaxone clearly deserves further evaluation for the therapy of meningitis; the optimal dose, dosing frequency (every 12 h or every 24 h), and duration of therapy remain to be determined.

Eficacia do moxalactam no tratamento de meningites purulentas causadas por Haemophilus infuenzae e Neisseria meningitidis. / Efficacy of moxalactam in the treatment of purulent meningitis caused by Haemophilus influenzae and Neisseria meningitidis

Foi avaliada a eficacia do moxalactam no tratamento de meningites em criancas, causadas por H. influenzae (27 casos) e N.meningitidis (6 casos). Dos 33 doentes tratados na dose de 100mg/Kg de peso (dose de ataque) e 50mg de 12/12 horas por via venosa, 32 curaram-se. A tolerancia ao produto foi muito boa, havendo alteracoes transitorias de transaminases e fosfatase alcalina; em um caso, houve hematoma posapendectomia, provavelmente relacionado ao uso deste antibiotico. Os niveis sericos e liquoricos do produto foram elevados; as concentracoes no liquor excederam de muito a concentracao bactericida minima dos germes infectantes. O moxalactam se mostrou seguro e eficaz como terapia primaria da meningite causada por H. influenzae e N.meningitidis em criancas

Moxalactam for the treatment of bacterial meningitis in children.

Increasing resistance to antibiotics in meningeal pathogens has stimulated a search for new antimicrobial agents for the treatment of bacterial meningitis. Moxalactam penetrates well into infected cerebrospinal fluid (CSF) and is highly active against most gram-negative bacteria. The clinical efficacy and safety of moxalactam in the treatment of childhood meningitis caused by Haemophilus influenzae (25 patients) or Neisseria meningitidis (five patients) was evaluated in a random, uncontrolled study. The penetration of the antibiotic into CSF was also evaluated in these patients and in another five children with bacterial meningitis. The clinical results were excellent, with 29 of 30 cases cured. The single adverse clinical reaction noted was the development of a wound hematoma in a postoperative patient; this problem may have been related to moxalactam therapy. The levels of moxalactam achieved in CSF greatly exceeded the minimal bactericidal concentrations for the infecting organisms. Moxalactam appears to be safe and effective as primary therapy for meningitis caused by H influenzae or N meningitidis.