The copper resistance operon copAB from Xanthomonas axonopodis pathovar citri: gene inactivation results in copper sensitivity

Xanthomonas axonopodis pv. citri (Xac) causes citrus canker and the completion of the Xac genome sequence has opened up the possibility of investigating basic cellular mechanisms at the genomic level. Copper compounds have been extensively used in agriculture to control plant diseases. The copA and copB genes, identified by annotation of the Xac genome, encode homologues of proteins involved in copper resistance. A gene expression assay by Northern blotting revealed that copA and copB are expressed as a unique transcript specifically induced by copper. Synthesis of the gene products was also induced by copper, reaching a maximum level at 4 h after addition of copper to the culture medium. CopA was a cytosolic protein and CopB was detected in the cytoplasmic membrane. The gene encoding CopA was disrupted by the insertion of a transposon, leading to mutant strains that were unable to grow in culture medium containing copper, even at the lowest CUSO4 concentration tested (0.25 mM), whereas the wild-type strain was able to grow in the presence of 1 mM copper. Cell suspensions of the wild-type and mutant strains in different copper concentrations were inoculated in lemon leaves to analyse their ability to induce citrus canker symptoms. Cells of mutant strains showed higher sensitivity than the wild-type strain in the presence of copper, i.e. they were not able to induce citrus canker symptoms at high copper concentrations and exhibited a more retarded growth in planta.

Variations in the sensitivity of different primers for detecting Wolbachia in Anastrepha (diptera: tephritidae)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Spatial distribution of canine Visceral Leishmaniasis in Ilha Solteira, São Paulo, Brazil

A Leishmaniose Visceral (LV) é causada por protozoários do gênero Leishmania e transmitida por flebotomíneos do gênero Lutzomyia, os quais vêm adaptando-se ao ambiente peridomiciliar, onde o cão é sua principal fonte de alimento, aumentando assim o risco de casos em humanos. Neste trabalho, foram utilizadas técnicas de geoprocessamento e de estastística espacial como contribuição à compreensão da dinâmica epidemiológica da LV na área urbana de Ilha Solteira-SP.

Aplicação da técnica de imunofluorescência direta para o diagnóstico da leishmaniose visceral canina em aspirado de linfonodo

Recentemente, foco de leishmaniose visceral canina (CVL) foi descrito na região noroeste do Estado de São Paulo - Brasil. O Hospital Veterinário - UNESP - Araçatuba, no ano de 2.000, desenvolveu 60 testes citopatológicos de casos suspeitos de leishmaniose usando aspirado por agulha fina (FNA). Os esfregaços de linfonodo foram corados pelo método de Romanowsky (Diff-Quik®) e observados em microscopia de luz. Os casos positivos mostraram formas amastigotas típicas de Leishmania livres ou em vacúolos de macrófagos. Sinais citopatológicos de reatividade do sistema linfo-histiocitário com ausência de parasitos foram também observados. Com o objetivo de implementar o diagnóstico da CVL, detectando parasitos e material antigênico nos esfregaços, aplicou-se a reação de imunofluorescência direta (IFD) usando anticorpo policlonal anti-Leishmania produzido em camundongo. Comparamos o método de IFD com a pesquisa direta do parasito em esfregaços corados pelo método de Romanowsky. Dos 60 cães com sinais clínicos da doença, o exame direto foi positivo em 50% (n=30), duvidoso em 36,7% (n=22) e negativo com reatividade do linfonodo em 13,3% (n=8). Quando os linfonodos foram submetidos a reação de IFD observamos reação positiva em 93,3% (n=56) e reação negativa em 6,7% (n=4). Nossos resultados mostraram que a reação de IFD apresentou alta sensibilidade quando comparada a pesquisa direta do parasito pela coloração de Romanowsky. A reação de IFD pode ser um método útil para confirmar os casos duvidosos da doença, onde as formas amastigotas não são identificadas com facilidade.

Bleomycin sensitivity in patients with familial and sporadic polyposis: a pilot study

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Experimental visceral leishmaniasis in high and low antibody - producer mice (selection IV-A)

A leishmaniose é uma infecção parasitária cuja imunidade protetora envolve a ativação de macrófagos. Neste trabalho avaliamos a susceptibilidade de camundongos H e L (bons e maus produtores de anticorpos, respectivamente) da seleção IV-A, à infecção com o protozoário L. donovani. Camundongos H infectados com 10(7) amastigotas por via intravenosa foram mais suscetíveis, apresentando maior carga parasitária tanto no fígado quanto no baço. Após 60 dias de infecção ambas as linhagens apresentaram um aumento no índice esplênico. Esta esplenomegalia foi conseqüência, pelo menos parcialmente, de um aumento no número de células esplênicas. Os resultados indicam que a seleção IV-A é susceptível à infecção com L. donovani e que dentro desta seleção a linhagem H apresenta maior suscetibilidade do que a linhagem L.

Reposição de cães em área endêmica para leishmaniose visceral

Esse trabalho objetivou estimar a reposição de cães em área endêmica para leishmaniose visceral, onde a eutanásia de animais soropositivos é indicada como medida de controle, e avaliar os motivos que levaram a aquisição ou não de novos animais. Houve a reposição em 44,5% dos casos, principalmente devido à necessidade de companhia ou guarda. O principal motivo para a não-reposição foi o temor da leishmaniose visceral.

Mapping oil spill environmental sensitivity in cardoso island state park and surroundings areas, São Paulo, Brazil

This study presents an environmental oil spill sensitivity map of Cardoso Island State Park, located in São Paulo state, Brazil, including some of its surrounding areas. This map was designed following the procedures determined by the Brazilian Federal Environment Organ (Ministry of the Environment), which separates coastal habitats in different littoral sensitivity indexes (LSI) to oil spills. We have also analysed some seasonal variations in morphologic and textural parameters at the local marine beaches that could affect their sensitivity, having found that they are more sensitive during summer due to a wider foreshore zone during these periods. Local most sensitive habitats are estuarine mangroves (LSI 10) and estuarine mud banks (LSI 9). Marine beaches were ranked LSI 3, and littoral rocky shores were subdivided in exposed flat rocky shores (LSI 1), boulder rocky shores (LSI 6) and sheltered rocky shores (LSI 8). Due to the elevated sensitivity of an estuarine system in the area, we considered necessary the installation of an Environmental Emergency Centre and the design of an emergency plan for the region in case of an accident resulting in oil spills within its vicinities. (C) 2007 Elsevier Ltd. All rights reserved.

Effect of tegument integrity on the light sensitivity in seeds of Cucumis anguria L

Cucumis anguria present dark germinating seeds at 25 degrees C. Seeds without the tegument are photosensitive germinating better in darkness than under continuous white light. However, pre-incubation at 40 degrees C for 48 hours allows the seeds to germinate under continuous white light and the incubation of naked seeds at -0.6MPa restored the light inhibition of seed germination. Our results suggest that the tegument interact with the phytochrome in the control of seed germination in part of the population of seed of C. anguria.

Saponins, IL12 and BCG adjuvant in the FML-vaccine formulation against murine visceral leishmaniasis

The FML antigen of Leishmania donovani, in combination with either Riedel de Haen (R), QuilA, QS21 saponins, IL12 or BCG, was used in vaccination of an outbred murine model against visceral leishmaniasis (VL). Significant and specific increases in anti-FML IgG and IgM responses were detected for all adjuvants, and in anti-FML IgG1, IgG2a and IgG2b and delayed type of hypersensitivity to L. donovani lysate (DTH), only for all saponins and IL12. The QS21-FML and QuilA-FML groups achieved the highest IgG2a response. QuilA-FML developed the strongest DTH and QS21-FML animals showed the highest serum IFN-gamma concentrations. The reduction of parasitic load in the liver in response to each FML-vaccine formulation was: 52% (P < 0.025) for BCG-FML, 73% (P < 0.005) for R-FML, 93% (P < 0.005) for QuilA-FML and 79.2% (P < 0.025) for QS21-FML treated animals, respectively. Protection was specific for R-FML and QS21-FML while the QuilA saponin treatment itself induced 69% of LDU reduction. The FML-saponin vaccines promote significant, specific and strong protective effects against murine visceral leishmaniasis. BCG-FML induced minor and non-specific protection while IL 12-FML, although enhancing the specific antibody and IDR response, failed to reduce the parasitic load of infected animals. (C) 2002 Elsevier B.V. Ltd. All rights reserved.

INVOLVEMENT OF SWIMMING-INDUCED ACUTE STRESS IN THE SENSITIVITY OF RAT VAS-DEFERENS TO NOREPINEPHRINE

1. The effects of swimming-induced stress on rat sensitivity to norepinephrine were studied.2. Through microscopic analysis of the stomach from swimming stressed rats significant ulceration was observed, confirming that the stress situation was really present.3. Sensitivity to norepinephrine either in the presence or in the absence of cocaine and propranolol in acutely swimming stressed rats was not altered significantly.4. Bilateral adrenalectomy was performed in rats 2 days before swimming and acute stress resulted in a supersensitivity to norepinephrine, indicating that adrenal glands may, at least, partially mediate the sensitivity to this drug in vasa deferentia isolated from these animals.

The pre-emptive effect of epidural ketamine on wound sensitivity in horses tested by using von Frey filaments

Objective To evaluate the pre-emptive analgesic effect of pre-incisional epidural ketamine.Study Design A blinded, randomized experimental study.Animals Sixteen mixed breed mares, 17.6 +/- 2.8 years old, weighing 352 +/- 32 kg.Methods In a pilot study, an incision was made on one lateral thigh using a lidocaine block and no further analgesics, and it was verified that the nociceptive threshold was lower on the incised side than nonincised side (p < 0.05), and that von Frey filaments evoked a pain response. The 16 animals were divided into group A (ketamine, n = 9) and B (saline, n = 7). An epidural catheter was inserted 24 hours before the trials, the thigh was shaved bilaterally, and the right side was blocked (incised side) using lidocaine. Twenty-five minutes later, ketamine (A) or saline (B) was administered epidurally. Five minutes later, a 10-cm. skin incision was made on the right side, and then sutured. Nociceptive threshold was determined with von Frey filaments at 1, 3, and 5 cm. around the incision at 15-minute intervals for 2 hours, then at 4, 6, and 8 hours. Behavioral alterations, heart and respiratory rates were recorded. Nociceptive thresholds from these points were averaged to obtain mean values at each time, converted to a logarithmic scale, and submitted to a nonparametric analysis (Mann-Whitney and one-way repeated measures anova test,p less than or equal to 0.05).Results After 8 hours, the global range score revealed reduced hyperalgesia (p < 0.01) around the incision in 92% (4.65-4.27) of evaluated intervals in group A (ketamine). There were no significant changes in behavior, heart and respiratory rates,Conclusions It was concluded that pre-emptive epidural ketamine reduced post-incisional pain in the horse, and that von Frey filaments were able to quantify cutaneous sensitivity after tissue damage.Clinical relevance Epidural ketamine injection can reduce post-incisional sensitivity in the horse.