Evaluation of α-D-ribofuranose (D-ribose) toxicity after intravenous administration to rabbits.

Rapid intravenous administration of D-ribose may result in a significant reduction in cellular damage in patients with sudden ischemic insults. The development of an effective and clinically safe therapeutic regimen using the intravenous route in critically ill patients especially with cardiac diseases requires a comprehensive assessment of potential toxic effects of the drug in laboratory animals and in human beings. The potential clinical, behavioral, hematological, biochemical, gross pathological and histological toxic effects associated with the intravenous administration of D-ribose in rabbits for 28 days were evaluated in this study. Except for an increase in neutrophil percentage in male rabbits in the D-ribose-treated groups, there were no statistically significant toxic effects induced by daily intravenous administration of the drug in male and female rabbits. Results of this study suggest that D-ribose administered intravenously for 28 days in the rabbit exhibited no toxicity at 420 mg/kg.

Small cell lung carcinoma presenting with acute disseminated encephalomyelitis.

Acute disseminated encephalomyelitis (ADEM) is a demyelinating disease characterised by subcortical high-signal white matter lesions on T2 weighted MRI. It most commonly occurs in children following an acute viral illness. We present a case study in which ADEM was the presenting condition in an adult female with small cell lung carcinoma. We discuss the evidence in the literature suggesting that ADEM may be viewed as a paraneoplastic syndrome.

Relationship between postoperative infectious complications and glycemic control for diabetic patients in an orthopedic hospital in Kuwait.

OBJECTIVE: To study the relationship between postoperative infectious complications and glycemic control for diabetic patients in an orthopedic hospital in Kuwait. SUBJECTS AND METHODS: Patients who underwent surgical orthopedic procedures between 2006 and 2007 were identified to provide demographic and clinical informations including age, gender, type of surgery, length of operation, HbA(1c) values, nature of specimens and species of the isolated pathogens. HbA(1c) <7% was used as the breaking point for diabetic control and occurrence of postoperative complications. Primary outcomes with infectious complications, including urinary tract infection, surgical site infection (SSI), lower respiratory tract infection and sepsis with different isolated pathogens were identified at least 48 h postoperatively. RESULTS: Of 318 diabetic patients who underwent surgical operations, 90 (28.3%) developed postoperative complications; HbA(1c) <7% was significantly associated with decreased infectious complications with an adjusted odds ratio of 2.51 (95% confidence interval, 1.20-2.89). Regarding types of complications, urinary tract infectious complications were significantly higher among those patients with HbA(1c) > or =7% (p < 0.0001), while other complications (SSI, lower respiratory tract infection and sepsis) showed nonsignificant differences (p > 0.05). CONCLUSIONS: Our study confirmed a close association between preoperative glucose control indicated by HbA(1c) levels <7% and a decreased risk of postoperative infectious complications. Ideally, preoperative blood sugar should be controlled prior to elective surgery. Prophylaxis by antibiotics with preoperative patient preparation, proficient surgical technique and postoperative wound care is recommended for uncontrolled diabetics subjected to surgery.

Genes encoding homologues of three consecutive enzymes in the butyrate/butanol-producing pathway of Clostridium acetobutylicum are clustered on the Clostridium difficile chromosome.

Screening of a Clostridium difficile lambda EMBL3 gene library with antisera raised against C. difficile culture supernatant identified several clones expressing a 31-kDa protein. A 1.8-kb HindIII fragment subcloned from one of the clones was sufficient for expression of the 31-kDa polypeptide. Southern blot analysis showed a region homologous to this fragment to be present in all of 13 different C. difficile strains tested. Sequence analysis of the 1.8-kb fragment revealed three adjacent open reading frames. A database search showed that these three open reading frames appeared to encode homologues of three consecutive enzymes in the butanol/butyrate-producing pathway of Clostridium acetobutylicum (crotonase, beta-hydroxybutyryl coenzyme A dehydrogenase and thiolase).

Characterisation of Clostridium difficile strains by polymerase chain reaction with toxin A- and B-specific primers.

A total of 218 Clostridium difficile strains was examined for production of toxin A by ELISA, production of toxin B by a cytotoxin assay and the presence of toxin A and B gene-associated sequences by the polymerase chain reaction (PCR). After saturation amplification with toxin B-specific primers, the characteristic amplification product (591 bp) was detected in all 184 toxigenic strains examined. PCR with toxin A-specific primers gave positive results with all but one of the toxigenic strains. By contrast, PCR with toxin A- and toxin B-specific primers yielded negative results with all 34 non-toxigenic strains tested. This suggests that PCR detection of either the toxin A or B gene is a good indication of toxin production. PCR did not require DNA extraction or hybridisation and was convenient, sensitive and rapid. Toxigenic C. difficile could be detected in mixed cultures, suggesting a role for PCR in the identification of toxigenic C. difficile in primary culture.

Alpha thalassaemia in Saudis.

The alpha-thalassaemias are group of inherited anaemias. Their severity is known to increase with the number of alpha-globin genes deleted. Employing different types of restriction enzymes, we found that alpha-thalassaemia-2 are more common than held previously. On the basis of our results we also anticipate that the haplotype alpha alpha alpha anti3.7/ occurs at a higher frequency.

Cytogenetic effects of dacarbazine on mouse bone marrow cells in vivo.

The mutagenicity of dacarbazine was assayed in an in vivo test utilizing mouse bone marrow cells. The dose rates used in the experiments were computed according to the standard surface area of the mouse and were proportional to the human dose rate. These were 0.27, 0.44 and 0.60 mg/30 g body weight, each given twice daily at an interval of not less than 6 h. The duration of drug treatment was 24, 48 and 72 h. This alkylating agent proved to be mitodepressive and produced a 3-fold reduction in the mitotic index. The drug also induced chromosome anomalies mainly in the form of chromatid gaps and breaks. These anomalies were proportional to dose rate and duration of drug treatment.

Cytological studies of certain desert mammals of Saudi Arabia. 6. First report on chromosome number and karyotype of Acomys dimidiatus.

The diploid chromosome number is 2n = 38. The fundamental number is 70. The autosomes consist of 11 pairs of metacentric, 5 pairs of submetacentric and 2 pairs of acrocentric chromosomes. The sex chromosomes are both acrocentric, the X-chromosome is the largest.

Effects of temperature on the replication of chromosomal DNA of Xenopus laevis cells.

DNA fibre autoradiography has been used to study the effects of temperature on the replication of chromosomal DNA of Xenopus laevis cells in tissue culture at 18, 23 and 28 degrees C. Pulse/stepdown labelling shows that the DNA replicates bidirectionally. Origin-to-origin distances (initiation intervals) vary, but the range of and the mean initiation intervals at all three temperatures are much the same. The mean interval between initiation points is of the order of 60 to 66 microns. Staggering of initiation is evident at all three temperatures. Evidence against the existence of replication termini is provided. The rates of progress of DNA replication forks are 6 microns/h at 18 degrees C, 10 microns/h at 23 degrees C and 16 microns/h at 28 degrees C.