Advantages and Applications of Cryopreservation in Fisheries Science

Cryopreservation is a long-term storage technique to preserve the biological material without deterioration for extended period of time at least several thousands of years. The ability to preserve and store both maternal and paternal gametes provides a reliable source of fish genetic material for scientific and aquaculture purposes as well as for conservation of biodiversity. Successful cryopreservation of fish sperm have been achieved for more than 200 fish species and many fish species have been adequated for the purpose of cryobanking. Cryopreservation of fish embryo is not viable, mainly because of the same limitations as in fish oocytes, i.e., high chilling sensitivity and low membrane permeability. However, cryopreservation of isolated embryonic cells is another option for preserving both maternal and paternal genome. In this paper, an overview of the current state of aquatic species is followed by a discussion on the sperm, embryos, oocytes and embryonic cells - blastomeres.

Nutritional deficiency in citrus with symptoms of citrus variegated chlorosis disease / Deficiência nutricional em citros com sintomas da doença da clorose variegada dos citros

It is well known that citrus plants that have been infected by Xylella fastidiosa display nutritional deficiencies, probably caused by production of extracellular polymers by the bacteria that block normal nutrient flow through the xylem. The aim of this work was to study the mineral composition of specific foliar areas in different stages of infection in citrus. Thus, the concentrations of macro and micronutrients in leaves of citrus infected by X. fastidiosa were measured. Samples from four infected citrus orchards in the State of São Paulo, Brazil, were respectively collected from Santa Rita do Passa Quatro, Neves Paulista, Gavião Peixoto and Paraíso counties. The presence of X. fastidiosa in leaves was confirmed by polymerase chain reaction (PCR) using specific PCR primers. To understand the variation in leaf-nutrient content in citrus plants, we used foliar nutrient values from control (non-symptomatic) plants as a reference. Chemometric analysis showed that the deficiency of P and K in symptomatic trees for all orchards and high concentrations of Fe, Mn and Zn were observed in chlorotic areas, although other studies revealed deficiency of zinc in leaves. This is the first report showing that a correlation between chlorotic citrus leaf and higher concentrations of Fe, Mn and Zn are observed when infected and healthy plants were compared.

Já é bem conhecido que cultivares cítricas que foram infectadas pela bactéria Xylella fastidiosa apresentam deficiências nutricionais devido à produção de polímero extracelular por esta bactéria, o qual bloqueia o fluxo normal de nutriente pelo xilema. O objetivo deste trabalho foi o de estudar a composição mineral em áreas foliares específicas em diferentes fases de infecção na planta. Assim, as concentrações de macro e micronutrientes em folhas de citros infectados por X. fastidiosa foram quantificadas. Foram coletadas amostras de quatro pomares cítricos infectados localizados em: Santa Rita do Passa Quatro, Neves Paulista, Gavião Peixoto e Paraíso, no Estado de São Paulo. A presença de X. fastidiosa em folhas foi confirmada através de reação da polimerase em cadeia (PCR) usando iniciadores específicos. Para entender a variação no conteúdo de nutriente foliar em plantas cítricas, utilizou-se de valores de nutrientes foliares de plantas não sintomáticas (controle) como referência. A análise quimiométrica mostrou que a deficiência de P e K em plantas sintomáticas e concentrações altas de Fe, Mn e Zn foram presentes em áreas foliares cloróticas, embora outros estudos mostrem a deficiência de zinco em folhas. Este é o primeiro relato indicando que uma correlação entre folhas cítricas cloróticas e elevadas concentrações de Fe, Mn e Zn foi observada quando plantas infectadas e saudáveis foram comparadas.

An alternative method for Staphylococcus aureus DNA isolation / Metodologia alternativa para extração de DNA genômico de Staphylococcus aureus

This study describes a rapid procedure for the isolation of genomic DNA from Staphylococcus aureus that yielded a good amount of high quality DNA for the amplification of staphylococcal enterotoxins genes (A, B, C, D, and E) and the TSST-1 gene as well as enzymatic restriction (HaeIII) from environmental isolates. With this method, it was possible to detect these genes in a sample containing as little as 10(5) cells with positive PCR reactions obtained from approximately 10pg of DNA in a final reaction volume of 25µl.

Descreve-se um procedimento rápido para extração de DNA genômico de isolados de Staphylococcus aureus capaz de produzir DNA estafilocócico em qualidade e quantidade suficiente para a amplificação de genes que codificam enterotoxinas estafilocócicas (A - E) e para TSST-1 e restrição enzimática (HaeIII) de isolados ambientais. O método proposto foi capaz de detectar esses genes em um produto de extração contendo tanto quanto 10(5) células, e reações positivas de PCR foram obtidas de aproximadamente 10pg de DNA.

Influencia de las hormonas tiroideas en la regulación de la función endócrina del ovario / Influences of the htyroid hormones in the regulation of the ovary endocrine function

Los autores hacen hincapié en que las alteraciones tiroideas pueden influir sobre la vida reproductiva de la mujer. Destacan que las disfunciones tiroideas en el embarazo, no tratadas, pueden alterar el crecimiento y desarrollo fetal. En los casos de hipotiroidismo subclínico, se recomienda tratamiento sustitutivo por tres razones: 1) el hipotiroidismo subclíncio es una enfermedad crónica que evoluciona en un lato porcentaje hacia un hipotiroidismo manifiesto. 2) A pesar de ser subclínico se acompaña de trastornos metabólicos y lipídicos con mayor riesto de enfermedad coronaria. 3) La terapia sustitutiva revierte los trastornos endócrinos preexistentes

Epidemiology of swine toxoplasmosis in Taiwan.

From July 1987 to June 1988, serum samples from 3,880 pigs from eight geographic locations in Taiwan were examined for Toxoplasma gondii antibodies using the latex agglutination test (LA test) and IgM-enzyme-linked immunosorbent assay (IgM-ELISA). A total of 1,073 samples (27.65%) were positive by the LA test. The percentage of positive reactions varied by location as follows: Taoyuan 44.44% (128/288), Taichung 27.60% (183/663), Tainan 22.28% (119/534), Kaohsiung 19.60% (98/500), Pingtung 17.92% (86/480), Hualien 33.95% (163/480), Ilan 31.66% (152/480), Taitung 31.64% (144/455). In the IgM-ELISA 1,828 of 3,880 samples (47.11%) were positive and the distribution of positive reactions were: Taoyuan 59.02% (170/288), Taichung 53.69% (356/663), Tainan 52.24% (279/534), Kaohsiung 54.60% (273/500), Pingtung 18.95% (91/480), Ilan 47.50% (228/480), Hualien 42.70% (205/480), Taitung 49.67% (226/455). On one farm, 20 of 120 sows experienced abortion and stillbirths due to Toxoplasma gondii. Lesions and T. gondii were found in lungs, liver, kidneys, heart, and placenta of one of the aborted fetuses.

Indirect hemagglutination antibody titers for Entamoeba Histolytica in dried filter paper blood and sera.

Serum and elutates from dried filter paper bloods from 404 patients with and without amebic liver abscess (ALA) were tested for Entamoeba histolytica antibodies by the indirect hemagglutination test. Eighty-nine percent of the sera from patients with ALA were positive (titers greater than or equal to 1 : 128) and 94% of those without ALA negative. Fifty-five percent of the filter paper bloods from ALA patients were positive. Overall agreement was 80% for positives and negatives and the correlation coefficient between the methods showed a linear relationship (r = 0.77). Although the quantity of sera available from dried filter paper bloods is limited and some antibody activity may be lost, the method should be of value in seroepidemiologic studies where venous bloods are not easily obtained.