In vitro evaluation of the antimicrobial effects of different intracanal medications in necrotic immature teeth.

AIM: This was to assess the antimicrobial effectiveness of pastes used as intracanal medicaments against Enterococcus faecalis in necrotic immature teeth. METHOD: An agar-disc diffusion method over a period of 30 days was used. The following medications were analysed: triple antibiotic paste (TAP) I; double antibiotic paste (DAP) I; DAP I with calcium hydroxide; calcium hydroxide paste with saline solution 0.9 %; calcium hydroxide paste with chlorhexidine 2 % gel; DAP II; DAP II with zinc oxide; DAP II with calcium hydroxide; and saline solution 0.9 % as control. The diameters of the halos of inhibition (in mm) of tested medicaments were determined and analysed with one-way analysis of variance and Tukey's post hoc tests. RESULTS: TAP I (G1) was significantly more effective against E. faecalis, and showed the largest halo of inhibition during all the experiments. DAP groups (G2 and G6) also showed inhibiting bacterial growth with said inhibition remaining stable throughout the 30-day period. In contrast, G4 and G5 groups, in which Ca(OH)2 was added to saline and chlorhexidine, had no antibacterial effect. CONCLUSIONS: TAP and DAP showed better antibacterial efficacy and remained active for 30 days. Combination of Ca(OH)2 with antibiotics should be avoided, due to the possibility of antibiotic hydrolysis.

Influence of catalase and pre-freezing equilibration on post-thaw semen quality and conception rate in ewes laparoscopically inseminated

The aim of this study was to investigate the effects of catalase and pre-freezing equilibration during ram sperm cryopreservation on motility and membrane and acrosomal integrity of frozen-thawed semen, as well as conception rate following laparoscopic timedinsemination. Semen was collected from four mature Dorper rams, pooled and diluted in Tris egg-yolk extender basic solution (CON), or this solution supplemented with catalase (CAT; 20 U/100 × 106 sperm). Extended semen was packaged in 0.25 ml mini straws (25 × 106 sperm/straw), chilled (to 5°C), and then either frozen immediately (CON and CAT) or maintained at 5°C for 12 h of pre-freezing equilibration (CON12 and CAT12). Immediately after thawing and at 1 h after incubation at 37°C, kinematic parameters (CASA), plasma membrane integrity (PI-FITC), and acrosomal status (FITC-PNA) of sperm were assessed. There were no significant differences among the four groups on sperm traits evaluated immediately postthaw. However, after 1 h of incubation, total motility (46.7 and 25.0%) and plasma membrane integrity (38.7 and 25.7%) were higher (P < 0.05) in CAT12 than CON. When these two treatments were used for laparoscopic timed artificial insemination of ewes (with synchronized ovulation), conception rate was similar for CAT12 and CON (32.8%, n = 61 vs. 27.3%, n = 55). In conclusion, the combination of catalase and pre-freezing equilibration resulted in significantly improved quality of post-thawed ram semen without affecting conception rate in fixed-time laparoscopically intrauterine inseminated ewes.(AU)

Influence of catalase and pre-freezing equilibration on post-thaw semen quality and conception rate in ewes laparoscopically inseminated

The aim of this study was to investigate the effects of catalase and pre-freezing equilibration during ram sperm cryopreservation on motility and membrane and acrosomal integrity of frozen-thawed semen, as well as conception rate following laparoscopic timedinsemination. Semen was collected from four mature Dorper rams, pooled and diluted in Tris egg-yolk extender basic solution (CON), or this solution supplemented with catalase (CAT; 20 U/100 × 106 sperm). Extended semen was packaged in 0.25 ml mini straws (25 × 106 sperm/straw), chilled (to 5°C), and then either frozen immediately (CON and CAT) or maintained at 5°C for 12 h of pre-freezing equilibration (CON12 and CAT12). Immediately after thawing and at 1 h after incubation at 37°C, kinematic parameters (CASA), plasma membrane integrity (PI-FITC), and acrosomal status (FITC-PNA) of sperm were assessed. There were no significant differences among the four groups on sperm traits evaluated immediately postthaw. However, after 1 h of incubation, total motility (46.7 and 25.0%) and plasma membrane integrity (38.7 and 25.7%) were higher (P < 0.05) in CAT12 than CON. When these two treatments were used for laparoscopic timed artificial insemination of ewes (with synchronized ovulation), conception rate was similar for CAT12 and CON (32.8%, n = 61 vs. 27.3%, n = 55). In conclusion, the combination of catalase and pre-freezing equilibration resulted in significantly improved quality of post-thawed ram semen without affecting conception rate in fixed-time laparoscopically intrauterine inseminated ewes.

A dose-response curve for biodosimetry from a 6 MV electron linear accelerator.

Biological dosimetry (biodosimetry) is based on the investigation of radiation-induced biological effects (biomarkers), mainly dicentric chromosomes, in order to correlate them with radiation dose. To interpret the dicentric score in terms of absorbed dose, a calibration curve is needed. Each curve should be constructed with respect to basic physical parameters, such as the type of ionizing radiation characterized by low or high linear energy transfer (LET) and dose rate. This study was designed to obtain dose calibration curves by scoring of dicentric chromosomes in peripheral blood lymphocytes irradiated in vitro with a 6 MV electron linear accelerator (Mevatron M, Siemens, USA). Two software programs, CABAS (Chromosomal Aberration Calculation Software) and Dose Estimate, were used to generate the curve. The two software programs are discussed; the results obtained were compared with each other and with other published low LET radiation curves. Both software programs resulted in identical linear and quadratic terms for the curve presented here, which was in good agreement with published curves for similar radiation quality and dose rates.

A dose-response curve for biodosimetry from a 6 MV electron linear accelerator

Biological dosimetry (biodosimetry) is based on the investigation of radiation-induced biological effects (biomarkers), mainly dicentric chromosomes, in order to correlate them with radiation dose. To interpret the dicentric score in terms of absorbed dose, a calibration curve is needed. Each curve should be constructed with respect to basic physical parameters, such as the type of ionizing radiation characterized by low or high linear energy transfer (LET) and dose rate. This study was designed to obtain dose calibration curves by scoring of dicentric chromosomes in peripheral blood lymphocytes irradiated in vitro with a 6 MV electron linear accelerator (Mevatron M, Siemens, USA). Two software programs, CABAS (Chromosomal Aberration Calculation Software) and Dose Estimate, were used to generate the curve. The two software programs are discussed; the results obtained were compared with each other and with other published low LET radiation curves. Both software programs resulted in identical linear and quadratic terms for the curve presented here, which was in good agreement with published curves for similar radiation quality and dose rates.

Visual attention in children with migraine: a controlled comparative study.

The aim of this study was to evaluate the visual attention of children with migraine and compare it with a control group. Thirty migrainous children and 30 controls without headache were subjected to a visual attention assessment with Trail Making Tests (TMT) A/B, Letter Cancellation Test, and the Brazilian computerized test Visual Attention Test, third edition. The migraine group was evaluated after 2 days without headache. The migraine group had an inferior performance compared with the control group on TMT A (P = 0.03) and B (P = 0.001), and more errors on tasks 1 (P = 0.032) and 2 (P = 0.015) of the Visual Attention Test, presenting difficulty with selective and alternate attention. Attention is a neurological function that depends on structures such as the brainstem, cerebral cortex and the limbic system and on neurotransmitters such as dopamine and noradrenaline. The neurochemical aspects involved in the physiopathology of migraine and attention mechanisms probably predispose these children to visual attention deficits.

Ocorrência de aflatoxina m1 em leite comercializado em alguns municípios do estado de são paulo / Occurrence of m1 aflatoxin in milk commercialized in some cities of são paulo state, brazil

RESUMO A aflatoxina M1 (AFM1) tem sido detectada em leite de animais alimentados com ração contaminada por aflatoxina B1(AFB1). A ocorrência de aflatoxina M1 no leite de vacas lactantes é uma questão de saúde pública, pois o leite e seus derivados são consumidos por bebês, crianças e adultos em todo mundo. Essa toxina é classificada como possível carcinógeno para o homem (classe 2B). O objetivo deste trabalho foi verificar a qualidade do leite consumido em algumas regiões do Estado de São Paulo, quanto ao teor de aflatoxina M1. Foram analisadas 43 amostras de leite comercial, coletadas em 27 municípios do Estado de São Paulo. A determinação de AFM1 em leite foi realizada empregando-se coluna de imunoafinidade para a purificação e detecção por cromatografia líquida de alta eficiência em fase reversa. AFM1 foi detectada em 17 (39,5%) das 43 amostras analisadas, sendo que 64,7% destas amostras apresentavam concentrações acima do limite máximo permitido pela legislação (0,5 µg/L).

ABSTRACT The M1 aflatoxin (AFM1) has been detected in milk from animal fed with feed contaminated by aflatoxin B1 (AFB1) contaminated. This toxin is a possible carcinogenic to humans (2B class). This is a potential public health problem, because young individuals are among the greater milk consumers and more sensitive to it effects. This study was developed to determine AFM1 in pasteurized milk in same regions São Paulo state. Forty-three samples colected in several cities were analized. The method used for the M1 aflatoxins purification was the immunoafinity column, with subsequent detection by reverse phase HPLC. AFM1 was detected in 17 (39.5%) out of 43 samples, 64.7% of the contaminated samples were above 0.5 µg/L

Biflavonoids inhibit the production of aflatoxin by Aspergillus flavus

The biflavonoids 6,6"-bigenkwanin, amenthoflavone, 7,7"-dimethoxyagastisflavone and tetradimethoxybigenkwanin isolated from Ouratea species were tested for inhibitory activity on Aspergillus flavus cultures. Suspensions of Aspergillus flavus spores were inoculated into 50 ml of YES medium at different biflavonoid concentrations: 5 and 10 æg/ml for 6,6"-bigenkwanin, amenthoflavone and 7,7"-dimethoxyagastisflavone, and 5, 10, 15 and 20 æg/ml for tetradimethoxybigenkwanin. The four biflavonoids showed inhibitory activity on aflatoxin B1 and B2 production (P<0.001), but did not inhibit fungal growth at the concentration tested (P>0.05). These results show that biflavonoids can be used for the development of agents to control aflatoxin production

Biflavonoids inhibit the production of aflatoxin by Aspergillus flavus.

The biflavonoids 6,6"-bigenkwanin, amenthoflavone, 7,7"-dimethoxyagastisflavone and tetradimethoxybigenkwanin isolated from Ouratea species were tested for inhibitory activity on Aspergillus flavus cultures. Suspensions of Aspergillus flavus spores were inoculated into 50 ml of YES medium at different biflavonoid concentrations: 5 and 10 microg/ml for 6,6"-bigenkwanin, amenthoflavone and 7,7"-dimethoxyagastisflavone, and 5, 10, 15 and 20 microg/ml for tetradimethoxybigenkwanin. The four biflavonoids showed inhibitory activity on aflatoxin B1 and B2 production (P<0.001), but did not inhibit fungal growth at the concentration tested (P>0.05). These results show that biflavonoids can be used for the development of agents to control aflatoxin production.

Correçäo de falhas ósseas diafisárias dos ossos do antebraço: emprego do enxerto ósseo em bloco do ilíaco / Correction of diaphyseal defect of the forearm bones: use of bone block graft from the iliac crest

Os autores relatam sua experiência com o emprego do enxerto ósseo em bloco da crista ilíaca na correçao de falhas diafisárias dos ossos do antebraço. A técnica foi utilizada em 12 pacientes (dez homens e duas mulheres, idade média de 29 anos), para falhas resultantes principalmente de fraturas fechadas ou expostas, que apresentaram infecçao e perda de substância óssea. As dimensoes médias do enxerto necessário para corrigir o defeito foram de 3,5 x 1,8cm. A aplicaçao do enxerto foi combinada com a fixaçao rígida com uma placa AO de compressao dinâmica de 3,5mm, permitindo mobilizaçao ativa. O enxerto integrou-se sem necessidade de procedimentos adicionais de enxertia em dez casos, num prazo médio de 17,2 semanas. A complicaçao mais freqüente foi a infecçao (quatro casos), controlada por meio de desbridamentos, limpeza cirúrgica e antibióticos. A análise comparativa das radiografias iniciais e finais mostrou perdas média de 30 por cento da massa óssea do enxerto, apesar da integraçao. Os autores concluíram que a técnica do enxerto em bloco para a correçao das falhas ósseas diafisárias do rádio e da ulna é relativamente fácil de executar e apresenta alto índice de sucesso.

Use of a bone block graft from the iliac crest with rigid fixation to correct diaphyseal defects of the radius and ulna.

We report our experience with the use of a bone block graft from the iliac crest to correct diaphyseal defects of the forearm bones. The technique was used in 12 patients (ten men and two women, average age 29 years) for defects resulting mainly from either closed or compound fractures, which later developed infection and bone tissue loss. The average dimensions of the graft required to correct the defect was 3.5 x 1.8 cm. The graft application was combined with rigid fixation with an AO 3.5 mm DCP plate, permitting early active motion. The graft incorporated without any additional grafting procedure in ten cases within 17.2 weeks on average. The most frequent complication was infection (four cases), controlled by means of debridement, cleansing and antibiotics. A comparative analysis of the immediate and final radiographs of the graft showed an average 30% loss of bone mass despite integration. We conclude that the technique of bone block grafting to correct diaphyseal defects of the radius or ulna is relatively easy to carry out and has a high success rate.