The rabbit alpha-like globin gene cluster is polymorphic both in the sizes of BamHI fragments and in the numbers of duplicated sets of genes

The alpha-like globin gene cluster in rabbits contains embryonic zeta- globin genes, an adult alpha-globin gene, and theta-globin genes of undetermined function. The basic arrangement of genes, deduced from analysis of cloned DNA fragments, is 5'-zeta 0-zeta 1-alpha 1-theta 1- zeta 2-zeta 3-theta 2-3'. However, the pattern of restriction fragments containing zeta- and theta-globin genes varies among individual rabbits. Analysis of BamHI fragments of genomic DNA from 24 New Zealand white rabbits revealed eight different patterns of fragments containing zeta-globin genes. The large BamHI fragments containing genes zeta 0 and zeta 1 are polymorphic in length, whereas a 1.9-kb fragment containing the zeta 2 gene and the 3.5-kb fragment containing the zeta 3 gene do not vary in size. In contrast to this constancy in the size of the restriction fragments, the copy number of the zeta 2 and zeta 3 genes does vary among different rabbits. No length polymorphism was detected in the BamHI fragments containing the theta-globin genes, but again the copy number varies for restriction fragments containing the theta 2 gene. The alpha 1- and theta 1-globin genes are located in a nonpolymorphic 7.2-kb BamHI fragment. The combined data from hybridization with both zeta and theta probes shows that the BamHI cleavage pattern does not vary within the region 5'-alpha 1-theta 1- zeta 2-zeta 3-theta 2-3', but the pattern genomic blot-hybridization patterns for the progeny of parental rabbits with different zeta-globin gene patterns shows that the polymorphic patterns are inherited in a Mendelian fashion. Two different haplotypes have been mapped based on the genomic blot-hybridization data. The variation in the alpha-like globin gene cluster in the rabbit population results both from differences in the copy number of the duplication block containing the zeta-zeta-theta gene set and from the presence or absence of polymorphic BamHI sites.      

Misidentification of two Brazilian triatomes, Triatoma arthurneivai and Triatoma wygodzinskyi, revealed by geometric morphometrics

Triatoma arthurneivai Lent & Martins and Triatoma wygodzinskyi Lent (Hemiptera: Reduviidae) are two Brazilian species found in the sylvatic environment. Several authors may have misidentified T. arthurneivai and consequently published erroneous information. This work reports the use of geometric morphometric analysis on wings in order to differentiate T. arthurneivai and T. wygodzinskyi, and thus to detect possible misidentifications. Triatomines collected from the field in the states of Minas Gerais and São Paulo, and from laboratory colonies, were used. Analyses show a clear differentiation between specimens of T. arthurneivai and T. wygodzinskyi. This indicates that T. arthurneivai populations from São Paulo state were misidentified and should be considered as T. wygodzinskyi. This study also suggests that T. arthurneivai is an endemic species from Serra do Cipó, Minas Gerais state.     

D-003, a potential antithrombotic compound isolated from sugar cane wax with effects on arachidonic acid metabolites

D-003 is a natural mixture of higher primary saturated aliphatic acids purified from sugar cane wax, whose main component is octacosanoic acid followed by triacontanoic, dotriacontanoic, and tetratriacontanoic acids. D-003 inhibits platelet aggregation and arterial thrombosis experimentally induced in a dose-dependent fashion. This study was undertaken to investigate the effects of D-003 (25 and 200 mg/kg) in experimental models of venous thrombosis and on plasma levels of two metabolites from arachidonic acid (AA) : thromboxane A(2) (TxA(2)) and prostacyclin (PgI(2)). D-003 orally administered as single doses of 200 mg/kg, but not at 25 mg/kg, significantly increased plasma levels of 6 keto PgF1alpha levels, a stable metabolite of PgI(2) in PPP obtained from collagen-stimulated blood (4 microg/ml) compared with control group. Nevertheless, levels of 6 keto PgF1alpha levels determined after 10 days of oral treatment with both doses of D-003 were significantly larger than those of the controls. Likewise, single and repeated oral doses of D-003 (25 and 200 g/kg) significantly reduced the TxB(2) and MDA plasma levels obtained from whole blood stimulated by collagen. Hence, TxB(2)/6 keto PgF1alpha ratio significantly decreased in animals treated with D-003. Single and repeated oral doses of D-003 (25 and 200 mg/kg) significantly reduced the weight of venous thrombus experimentally induced in rats. D-003 at single doses (400 mg/kg but not 200 mg/kg) significantly protected from death induced by endovenous infusion of collagen plus epinephrine in mice. The present results support that these effects of D-003 on AA metabolites could explain, at least partially, its antiplatelet and antithrombotic effects.     

Medroxyprogesterone priming and response to the ram effect in Corriedale ewes during the nonbreeding season

The "ram effect" (RE) is an inexpensive technique that allows farmers to obtain out-of-season lambs. Five hundred and ninety-six Corriedale ewes were used in three experiments to determine the effectiveness of different medroxyprogesterone (MAP) treatments associated with the ram effect during the nonbreeding season. The aim of the first experiment was to evaluate the effectiveness of short-term (6-day) MAP priming. We obtained similar results in estrus incidence and fertility after using MAP sponges for 6, 9, and 13 days. In the second experiment, we compared the effect of sponges containing 20, 40, or 60 mg of MAP used in 6-day priming. Estrous behavior and fertility were not affected by dosage. In the third experiment, 2.5mg of MAP was administered in single treatments 0, 1, 3, or 5 days before the introduction of the rams. Medroxyprogesterone administration 1, 3, or 5 days before the introduction of the rams concentrated estrus in ewes 17 to 20 days later.     

Response of the 1-5 day-aged ovine corpus luteum to prostaglandin F2alpha

The hypothesis that, in the ewe, prostaglandin (PG) F2alpha administration on day 3 after ovulation is followed by luteolysis and ovulation was tested using 24 animals. The ewes were treated with a dose of a PGF2alpha analogue (delprostenate, 160 microg) on days 1 (n=8), 3 (n=8) or 5 (n=8) after ovulation, was established by transrectal ultrasonography. Daily scanning and blood sampling were performed to determine ovarian changes and progesterone serum concentrations by radioinmunoassay. The treatment induced a sharp decrease of progesterone concentrations followed by oestrus and ovulation in all ewes treated on days 3 and 5 and in one ewe treated on day 1 (8/8, 8/8, 1/8; P<0.05). Seven ewes treated on day 1 did not respond to PGF2alpha treatment and had an inter-ovulatory cycle of normal length (17.4 +/- 0.5 days). However, the profile of progesterone concentrations during the cycle of these ewes was delayed 1 day (P<0.05) compared with a control cycle. The overall interval between PGF2alpha and oestrus for the 17 responding ewes was 42.4 +/- 2.3 h. In 15 of these ewes the ovulatory follicle was originated from the first follicular wave and the ovulation occurred at 60.8 +/- 1.8 h after PGF2alpha treatment. The other two responding ewes ovulated an ovulatory follicle originated from the second follicular wave between 72 and 96 h after treatment. These results support the hypothesis and suggest that refractoriness to PGF2alpha of the recently formed corpus luteum (CL) may be restricted to the first 1-2 days post-ovulation.     

Stat3 links activated keratinocytes and immunocytes required for development of psoriasis in a novel transgenic mouse model

Here we report that epidermal keratinocytes in psoriatic lesions are characterized by activated Stat3. Transgenic mice with keratinocytes expressing a constitutively active Stat3 (K5.Stat3C mice) develop a skin phenotype either spontaneously, or in response to wounding, that closely resembles psoriasis. Keratinocytes from K5.Stat3C mice show upregulation of several molecules linked to the pathogenesis of psoriasis. In addition, the development of psoriatic lesions in K5.Stat3C mice requires cooperation between Stat3 activation in keratinocytes and activated T cells. Finally, abrogation of Stat3 function by a decoy oligonucleotide inhibits the onset and reverses established psoriatic lesions in K5.Stat3C mice. Thus, targeting Stat3 may be potentially therapeutic in the treatment of psoriasis.     

Indirect Immunofluorescence Microscopy for Direct Detection of <Emphasis Type="Italic">Xylella fastidiosa</Emphasis> in Xylem Sap

The plant pathogen Xylella fastidiosa is the causative agent of a number of diseases of economically important crops, including Pierces disease that affects grapevines. Using a commercially available antibody specific for X. fastidiosa, we have established a protocol for microscopic identification of the bacterium by indirect immunofluorescence. This antibody clearly labels an uncharacterized antigen concentrated at a single pole of X. fastidiosa cells, but does not react with a non-Xylella control. This technique was also performed successfully on xylem exudates from several different plant genera and correlated well with standard enzyme-linked immunosorbent assay tests. These results establish a novel method for in situ assessment of X. fastidiosa infection from host plants.