Ancient conservation of trinucleotide microsatellite loci in polistine wasps

Several recent pieces of clinical evidence have demonstrated that reduction of cholesterol levels positively affects outcomes in both primary and secondary prevention of atherosclerotic vascular disease. The mechanism for the beneficial effects of cholesterol-lowering interventions has been attributed to decreased progression or actual regression of plaques as a consequence of reduced circulating LDL concentrations. Other mechanisms can be hypothesized, including a "stabilizing" effect on plaques, which would decrease chances of rupture, and an improvement of endothelial dysfunction, which would slow-down the progression of the disease. This review is aimed at offering an update on such mechanisms. The hypothesis of a direct action of cholesterol-lowering agents, in particular of statins, on endothelial functions, independently of LDL-lowering effects, will be discussed.     

Thirteen bovine microsatellite markers that are polymorphic in sheep

Macrolide resistance in disseminated Mycobacterium avium infection is of major concern in AIDS patients as these drugs represent the main component of combination therapy. Clarithromycin and azithromycin should not be used alone for the treatment and prophylaxis of the disease because of the risk of selecting resistant strains. We report the case of a clarithromycin resistant disseminated M. avium infection in an AIDS patient, acquired after long term monotherapy with clarithromycin for the treatment of cryptosporidiosis.     

Evaluation of loss of heterozygosity and microsatellite instability in human pterygium: clinical correlations

The histogenesis of carcinosarcoma of the breast is controversial. In the current case, the demarcation between the carcinomatous and sarcomatous components was distinct in all microscopic fields. Immunohistochemical analysis was negative for epithelial membrane antigen (EMA) and keratin in the sarcomatous component and was negative for desmin in the carcinomatous component, suggesting that this tumor could be derived from the two different stem cells. To determine the histogenesis of this tumor, both carcinomatous and sarcomatous lesions were microdissected from formalin-fixed tissues and DNAs were prepared by proteinase K digestion. PCR amplification of the human androgen receptor (HUMARA) short tandem repeat (STR), after Hpa II digestion of the genomic DNA, indicated that the patterns of X-chromosome inactivation were identical in both components. Moreover, both components contained the identical TGT --> TTT transversion in codon 275 of the p53 gene. These observations strongly support the hypothesis that this tumor is derived from a single totipotent stem cell.     

Pharmacokinetics and pharmacodynamics of tilmicosin in sheep and cattle

Tilmicosin is a long-acting macrolide antibiotic currently approved for treatment of bovine respiratory disease in the USA. Serum pharmacokinetics of tilmicosin were compared between cattle (major species) and sheep (minor species) after subcutaneous injection in order to evaluate a new potential application of the drug in currently nonapproved species. There were no significant differences in the elimination rates, maximum serum concentrations, half-lives (t1/2), areas under the curve (AUC), areas under the first-moment curve (AUMC), and mean residence times. Volume of distribution (Vd(area)) and clearance (Cl), when normalized by body weight, were also similar. The only significantly different parameter was time at which maximum drug concentration was reached (tmax), with sheep having the tmax of 3.9 h, compared to 0.5 h in cattle. Although macrolides are considered to be one of the safest anti-infective drugs, adverse cardiovascular effects of several macrolides have been reported. The cardiopulmonary effects of tilmicosin were monitored in healthy adult sheep after receiving a single subcutaneous (s.c.) injection of tilmicosin at the dose of 10 mg/kg, and no significant changes were found. The study indicates that tilmicosin can be used safely and effectively in sheep at the given dose, with no adverse cardiopulmonary effects.     

Loss of heterozygosity and microsatellite instability in de novo versus ex-adenoma carcinomas of the colorectum

Small adenocarcinomas of the colorectum showing no evidence of origin from an adenoma have been called de novo carcinomas, a name that implies an origin via a different molecular genetic mechanism than the usual colorectal carcinoma which develops from an adenoma. Using microsatellite analysis, 35 early (pT1) de novo and 36 pT1 ex-adenoma carcinomas were compared using 8 microsatellite loci at 6 different chromosomal loci (1p, 2p, 8p, 5q, 17p, and 18q) known or hypothesized to be important for colorectal carcinogenesis. The rate of loss of heterozygosity (LOH) at the 17p locus (near the p53 gene) was significantly higher in the de novo than in the ex-adenoma group (73 vs. 37%, P = 0.004). The rates of LOH at the other loci (including the APC and DCC genes) and the rate of MSI were not significantly different in the two groups. These results indicate that de novo carcinomas of the colorectum develop via a similar carcinogenetic pathway as conventional ex-adenoma carcinomas; however, their higher rate of LOH at 17p is evidence for a biologically more advanced lesion with more frequent p53 mutations, consistent with clinicopathological data indicating that de novo carcinomas are more aggressive than ex-adenoma carcinomas.     

Degradation and elimination of the anthelminitic 131I-rafoxanid in cattle and sheep

Rafoxanide, labelled by 131J, was applied orally in oily solution to cattle and sheep, 12 and 17 mg/kg bodymass, resp. The half time of 131J in blood in 12,5 and 10,5 d for sheep and cattle, resp., the compound is adsorbed to proteins in blood. In the milk a maximal level of 3-3,5 ppm (calculated as total 131J) after 4-6 d was measured. More detailed results regarding the metabolism of rafoxanide are hitherto not possible.     

Testicular acid phosphatases in cattle, sheep, guinea pig, and rabbit

Acid phosphatase activities were measured with five different substrates in the total homogenates as well as after gel filtration on Sepharose 6B and cellulose chromatography of bull, guinea pig, rabbit, and ram testes. The response of the hydrolysis rate to NaF (5 mmol/l), Co2+ (5 mmol/l) and Zn2+ (5 mmol/l) was also tested. In the total homogenate the hydrolysis of p-nitrophenyl phosphate was markedly activated by Co2+, while in the presence of Zn2+ an activation was recorded in guinea pig and some inhibition in the bull, rabbit, and ram testes. NaF caused a decline in the total acid phosphatase activity, particularly in guinea pig and ram. The gel filtration resulted in three separate activity peaks with p-NPP and beta-NP as substrates. N-ASBI-P, alpha-NP, and Tym-P gave only two peaks. After subsequent cellulose chromatography of the activities only peak II gave rise to two further activities. Peak I of gel filtration (enzyme I) was able to hydrolyze all substrates tested and was highly sensitive to NaF. Peak I of cellulose chromatography (enzyme II) also hydrolyzed p-NPP and beta-NP. It was rather resistant to NaF but sensitive to Zn2+. It was slightly activated by Co2+. Peak II of cellulose chromatography (enzyme IV) hydrolyzed only p-NPP and was markedly activated by Co2+ and Zn2+. The adult testes of bull, guinea pig, rabbit, and ram have a closely similar testicular acid phosphatase pattern. Due to relative differences in the concentrations of the four enzymes in the tissue, varying activity levels are recorded in the presence of different substrate and modifier combinations.     

Inactivation of Clostridium botulinum toxin by ruminal microbes from cattle and sheep

Toxin from Clostridium botulinum type C was rapidly inactivated during incubation in vitro with ruminal contents from either a cow or a sheep. Fractions of ruminal contents from which cells had been removed by high-speed centrifugation did not inactivate toxin. Inactivation was associated with fractions containing bacteria, whereas fractions containing protozoa and relatively few bacteria were much less active. This activity may help explain the relatively greater tolerance by ruminants to oral doses of botulinum toxin than to toxin administered by other routes. The results are also pertinent to assays for botulinum toxin from gastrointestinal samples obtained postmortem.     

"Woolly everlasting daisy" (Helichrysum blandoskianum) toxicity in cattle and sheep

Investigations into cattle mortalities suspected of being caused by the Woolly Everlasting Daisy (Helichrysum blandowskianum) revealed lesions of marked periacinar liver necrosis, vascular degeneration, widespread haemorrhages and oedema. Brains showed status spongiosus. These lesions were reproduced in cattle and sheep fed Helichrysum and in cattle given an intravenous injection of an extract of the plant.     

Morphological study of the surface structure of the omasal laminae in cattle, sheep and goats

The mucosal relief of the omasum in cattle, sheep and goats was examined by the naked eye, stereoscopic microscope and scanning electron microscope. The mucosal relief of the omasum showed wide variations both between and within these species. Omasal papillae on the laminae varied highly in shape, i.e. conical, rounded, claw-like, wart-like, finger-like etc. They decreased gradually in size from the oral to the aboral region of the omasal lamina. Ridge-like structures and linear arrangements of the papillae were also seen on the omasal laminae of cattle and sheep. Many grooves and folds were found on the lateral surface of the omasal papillae in adult cattle and on the inter-papillar surface of the laminae of all three species. The mucosal relief of the omasum in cattle seemed to be more well-developed than those of sheep and goats. Dietary effects on the omasal mucosa were also discussed.     

Antibody response in cattle, sheep and rats to infection with gamma-irradiated metacercariae of Fasciola hepatica

Cattle, sheep and rats were infected orally with gamma-irradiated (4 krad) metacercariae of fasciola hepatica, or with normal metacercariae. The antibody response was monitored in each host to metacercarial tegument (T0), juvenile tegument (T1), adult tegument (T2) and gut antigens. The response was examined at weekly intervals for cattle and sheep throughout 15 weeks of infection and four weeks after infection in rats, using an indirect fluorescent antibody labelling technique. It was found that the irradiated metacercariae engendered a normal humoral response to T0, T1 and gut antigens in all three hosts although the antibody levels were somewhat reduced due to an early death or stunting of the flukes. T0 and T1 appeared to be antigenically similar. Antibodies against T2 appeared late in the animals infected with gamma-irradiated metacercariae and the titres attained were considerably lower than in the controls. the T2 antigen stimulus in the animals given gamma-irradiated metacercariae was probably provided by flukes which 'broke through' the developmental barrier imposed by irradiation and which were found alive at autopsy.     

Applicability of cultured hepatocytes derived from goat, sheep and cattle in comparative drug metabolism studies

1. Using trimethoprim (TMP), scoparone (SCOP), ethylmorphine (EtM), 1-naphthol (1-N) and phenol red (PhR) as test substrates, biotransformation activities were investigated in cultured hepatocytes from male and female rat, male and female goat, and female sheep and cattle. 2. As compared with rat hepatocytes, the total culture cytochrome P450 content was relatively well maintained in ruminant hepatocytes. In 72 h, it decreased to approximately half the initial content, whereas in rat hepatocytes only 30% was maintained. In ruminant hepatocytes, sulphation of 1-N remained fairly stable, glucuronidation of PhR decreased gradually, and glucuronidation of 1-N increased during the 72-h culture period. 3. Oxidative metabolism of TMP was rapid in goat and sheep hepatocytes, as compared with rat hepatocytes, reflecting species differences in TMP pharmacokinetics in vivo. In contrast with rat hepatocytes, 6-O-demethylation was by far the major pathway of scoparone metabolism in ruminant hepatocytes. The glucuronidation and sulphation activities were similar among the species. 4. In goat liver cells, sex differences in some oxidative biotransformations were observed, females being more active than males. In rat hepatocytes, a reverse sex difference was observed. 5. In conclusion, cultured hepatocytes from agricultural target species appear a useful in vitro model to study comparative metabolism of veterinary drugs and other xenobiotics. Comparing rat and ruminant, sex and species differences and similarities in drug metabolism can be observed that reflect the in vivo situation.     

Frequent microsatellite instability and loss of heterozygosity in the region including BRCA1 (17q21) in young patients with gastric cancer

It is known that nearly 5% of gastric carcinomas arise under the age of 40. To elucidate genetic alterations in these patients, we performed studies using microsatellite assay in 27 gastric cancers under 35 years of age, composed of 5 well and 22 poorly differentiated adenocarcinomas. We detected replication errors (RERs) in 18 (67%) of 27 tumors, but no germline mutation in DNA mismatch repair genes (hMLH1 and hMSH2), except fory 3 somatic mutations in the hMLH1 gene. Loss of heterozygosity (LOH) at D17S855, located on chromosome 17q21 (BRCA1), was detected in 8 (40%) of 20 informative cases. In 12 (44%) of 27 cases, LOH on chromosome 17q12-21 including the BRCA1 was found in several neighboring markers in this region, while no mutation was found in the BRCA1 gene. Four (40%) of 10 scirrhous type gastric cancers exhibited wide allelic deletions on chromosome 17q12-21. These results overall suggest that young gastric cancer patients display highly frequent micro-satellite instability that might be due to defect of DNA repair system rather than hMLH1 and hMSH2. In addition, chromosome 17q12-21 including BRCA1 locus may contain a candidate for tumor suppressor gene, particularly in scirrhous type gastric cancers arising in young patients.     

DNA fingerprinting of the lizard Lacerta dahli: isolation of a genomic polymorphism of mini- and microsatellite loci

We performed a lateral approach for the release of post-traumatic stiffness of the elbow in 22 patients using a modified technique designed to spare the lateral ligaments. They were reviewed after a mean interval of 26 months. The total humeroulnar joint movement had increased from a mean of 74 degrees to 129 degrees and forearm rotation from a mean of 135 degrees to 159 degrees. Both pain and function in the elbow had improved significantly. This modified lateral approach allows release of post-traumatic contracture without disruption of the lateral collateral ligament or the origins of the extensor tendon at the lateral epicondyle of the humerus. The advantages include a simplified surgical procedure, less operative morbidity, and unrestricted rehabilitation.     

Loss of heterozygosity in neuroblastomas--an overview

Although previous studies have demonstrated a relatively high incidence of loss of heterozygosity (LOH) on chromosomes 1p, 11q and 14q in neuroblastoma, it is unclear whether LOH occurs specifically on these chromosomes or not. It might be due to the lack of allelotyping of neuroblastoma. When we assessed all 22 autosomes and chromosome X for LOH in 81 cases of neuroblastoma using 43 polymorphic DNA markers, a high incidence of LOH (> 30%) was observed on three chromosomal arms, 2q (30%), 9p (36%) and 18q (31%). Moreover, 9p LOH in the tumours showed statistically significant association with advanced stage of the disease and poor prognosis. Therefore, tumour suppressor genes on chromosomes 2q, 9p and 18q could be involved in the genesis and/or progression of neuroblastoma. Particularly, the gene on chromosome 9p may be associated with progression of neuroblastoma.     

Isolation and characterization of verocytotoxin-producing Escherichia coli O157 strains from Dutch cattle and sheep

In the periods from July to November 1995 and 1996, fecal samples from Dutch cattle and sheep were collected at the main slaughterhouses of The Netherlands, located at different geographic sites. The samples were examined for the presence of verocytotoxin (VT)-producing Escherichia coli (VTEC) of serogroup 0157. E. coli O157 strains could be isolated from 57 (10.6%) of 540 adult cattle, 2 (0.5%) of 397 veal calves, 2 (3.8%) of 52 ewes, and 2 (4.1%) of 49 lambs. Immunomagnetic separation with O157-specific-antibody-coated beads appeared to be significantly more sensitive than conventional plating for detection of the organism in feces. With the exception of two isolates from adult cattle which appeared to be negative for VT genes, all animal isolates were positive for both VT (VT1 and/or VT2) and E. coli attaching-and-effacing gene sequences, and therefore, they were regarded as potential human pathogens. Although genomic typing by pulsed-field gel electrophoresis revealed a wide variety of distinct restriction patterns, comparison of the 63 animal isolates with 33 fecal O157 VTEC strains previously isolated from humans with the diarrhea-associated form of the hemolytic-uremic syndrome by their phage types and VT genotypes showed a marked similarity between animal and human isolates: 30 (90.9%) of the 33 human isolates appeared to be of E. coli O157 strain types also isolated from cattle and sheep. It was concluded that Dutch cattle and sheep are an important reservoir of E. coli O157 strains that are potentially pathogenic for humans.     

Comparative genomic hybridization and loss of heterozygosity analyses identify a common region of deletion at 15q11.1-15 in human malignant mesothelioma

Comparative genomic hybridization analysis was performed to identify chromosomal imbalances in 24 human malignant mesothelioma (MM) cell lines derived from untreated primary tumors. Chromosomal losses accounted for the majority of genomic imbalances. The most frequent underrepresented segments were 22q (58%) and 15q1.1-21 (54%); other recurrent sites of chromosomal loss included 1p12-22 (42%), 13q12-14 (42%), 14q24-qter (42%), 6q25-qter (38%), and 9p21 (38%). The most commonly overrepresented segment was 5p (54%). DNA sequence amplification at 3p12-13 was observed in two cases. Whereas some of the regions of copy number decreases (i.e., segments in 1p, 6q, 9p, and 22q) have previously been shown to be common sites of karyotypic and allelic loss in MM, our comparative genomic hybridization analyses identified a new recurrent site of chromosomal loss within 15q in this malignancy. To more precisely map the region of 15q deletion, loss of heterozygosity analyses were performed with a panel of polymorphic microsatellite markers distributed along 15q, which defined a minimal region of chromosomal loss at 15q11.1-15. The identification of frequent losses of a discrete segment in 15q suggests that this region harbors a putative tumor suppressor gene whose loss/inactivation may contribute to the pathogenesis of many MMs.