Melipona mandacaia is a stingless bee endemic to northeast Brasil. We describe the M. mandacaia karyotype using C-banding technique. fluorochrome staining and treatment with restriction enzymes and discuss the position of this species in the context of the phylogeny of the genus. Melipona mandacaia has 2n = 18 (14 SM + 2 M + 2 A). Heterochromatin was detected in the pericentromeric region of pa...

The Escherichia coli fadR gene product, FadR, is a multifunctional regulator of fatty acid metabolism. In this work we have purified FadR by a two-step procedure employing two ion-exchange columns. The amino-terminal sequence of the purified protein confirms the sequence of the protein derived from analysis of the DNA sequence (DiRusso, C. C. (1988) Nucleic Acids Res. 16, 7995-8009) and indicat...

Mastitis is a costly disease of dairy cattle as it causes a loss in milk yield and milk quality in affected cows. Toll-like receptor (TLR) genes play a role in the host response to a variety of organisms including those inducing mastitis. In the present study, we investigated the polymorphism of TLR2, 4, 6 and 9 genes in Holstein cattle and ...

Length variation in D-loop mitochondrial DNA was observed after amplification with the polymerase chain reaction (PCR) in 28% of 195 evening bats, Nycticeius humeralis, from seven colonies. Nucleotide sequences of PCR products show that this heteroplasmy is characterized by an 81-bp region which is tandemly repeated five to eight times. Southern blots using PCR products as probes on HaeIII geno...

To study double-strand break (DSB)-induced mutations in mammalian chromosomes, we stably transfected thymidine kinase (tk)-deficient mouse fibroblasts with a DNA substrate containing a recognition site for yeast endonuclease I-SceI embedded within a functional tk gene. Cells were then electroporated with a plasmid expressing endonuclease I-SceI to induce a DSB, and clones that had lost tk funct...

An outbreak of infections affecting 311 patients who had undergone different invasive procedures occurred in 2004 and 2005 in the city of Belém, in the northern region of Brazil. Sixty-seven isolates were studied; 58 were from patients who had undergone laparoscopic surgeries, 1 was from a patient with a postinjection abscess, and 8 were from patients who had undergone mesotherapy. All isolates...

Background: Direct identification of Leishmania species in Giemsa-stained slides without parasite culturing in the areas where multiple species exist, is very helpful. This study was designed to isolate Leishmani spp. from Giemsa-stained smears and to characterize them by PCR technique. Methods: A total of 48 Giemsa-Stained slides from confirmed cases of leishmaniasis were examined under a ligh...

The strongest evidence for host specificity of mammalian trypanosomes comes from parasites of the subgenus Trypanosoma (Herpetosoma). Laboratory studies have shown that T. (Herpetosoma) species will not infect an alternative host. However, this has not been demonstrated in wild populations. We screened 560 bank voles (Clethrionomys glareolus) and 148 wood mice (Apodemus sylvaticus) for trypanos...