Cutaneous cryptococcosis among HIV infected patients

Five patients with HIV associated cutaneous cryptococcal infection are reported.     

Nucleotide sequence analysis of the L1 loop variable region of hexon gene of fowl adenovirus 4 isolates from India

Three fowl adenovirus 4 (FAV4) isolates from chicken and one from quail, all from Tamil Nadu, India were analyzed. The L1 loop variable region of hexon gene of these isolates was amplified by PCR and sequenced. The nucleotide sequences (442 bp) and deduced amino acid sequences of the four isolates were compared with those of other isolates of FAV4. The nucleotide sequences of the four isolates had a 98% homology with other Indian isolates and a 96% homology with Belgian and Russian isolates. The amino acid sequences of the four Indian isolates had a more than 98% homology with other Indian isolates and a more than 92% homology with Belgian and Russian isolates. Hence, the variable of L1 loop region of hexon gene was found to be highly homologous in all the FAV4 isolates tested both at nucleotide and amino acid level.     

Healthy monozygous twins do not recognize identical T cell epitopes on the myelin basic protein autoantigen

The T cell response against myelin basic protein (MBP) has been extensively studied in humans because of its putative role in the pathophysiology of multiple sclerosis (MS). Higher concordance rates in monozygous twins as well as an increased risk in relatives suggest the role of genetic factors in MS susceptibility. Very little is known about the shaping of T cell repertoire towards self antigens in humans and their contribution to disease susceptibility in autoimmune disorders. Here we report the comparative T cell epitope recognition patterns towards the MBP auto-antigen in healthy identical twins. We have established MBP-specific T cell lines from eight sets of twins and characterized their fine epitope specificity. Intra-pair comparison showed the co-existence of shared as well as distinct epitopes in six of eight pairs and a complete absence of concordant epitope recognition within two other pairs. These findings indicate that important differences in T cell repertoires against a self antigen may be observed between genetically identical healthy individuals, rendering difficult the interpretation of the differences which may be observed between identical twins discordant for an autoimmune disease.     

Adenosine nucleotides in rat bone measured by ion-pair reversed-phase high-performance liquid chromatography: effect of hemorrhagic shock, with and without retransfusion of blood

The measurement of bone adenosine nucleotides (ATP. ADP. AMP) using a simple HPLC procedure is described for rat tibia; the response to hemorrhagic shock with and without blood retransfusion is also described. With respect to the measurement of nucleotides, a number of validation criteria are met. In the anesthetized intact rat (Normal) there was a declining gradient of the three nucleotides, expressed as nmol per g dry matter, from proximal over middle to distal diaphysis, with the mean ratio ATP/ADP (0.21, 0.20, 0.20) and the mean energy charge (0.34, 0.31, 0.30) being low. Irrespective of the anatomic site, hemorrhagic shock of 30-min duration evoked a further decrease versus Normal of ATP, ATP/ADP and energy charge. Blood retransfusion after shock kept nucleotides and other variables in the proximal and distal, but not the middle, diaphysis within normal limits. It was concluded that: (i) bone nucleotides are reliably measurable by HPLC, allowing the described method to be recommended for wider use in bone research and related areas; (ii) in contrast to more parenchymatous tissues, low ATP, ATP/ADP and energy charge may be characteristic for long bones, pointing towards different energy metabolism; and (iii) bone is a "shock organ", reflecting blood hypoperfusion, O2 deficiency and decreased ATP in this situation.     

PCR-Enzyme Immunoassay for Detection of Streptococcus pneumoniae DNA in Cerebrospinal Fluid Samples from Patients With Culture-Negative Meningitis

A PCR-based assay was developed to amplify a conserved region of the pneumococcal autolysin gene. The amplified product was labelled with digoxigenin-labelled dUTP and was detected with a biotin-labelled probe in an enzyme immunoassay (EIA). The assay was initially tested with suspensions of various serotypes of Streptococcus pneumoniae and other gram-positive and gram-negative bacteria and was then applied to cerebrospinal fluid (CSF) specimens from patients with meningitis and those with other neurological disorders. The assay detected all the serotypes of S. pneumoniae tested, whereas all the other bacterial strains tested were negative. Seven of the 8 CSF specimens positive for pneumococcus by culture or latex agglutination (LA) were positive by PCR-EIA, whereas all 10 specimens positive for other organisms were negative. Among 11 patients with clinically diagnosed meningitis but with negative culture and LA results, 5 were positive by PCR-EIA. The assay was negative for all but one patient without meningitis; it was positive with the CSF from a child with immunodeficiency and pneumococcal abscesses on the scalp. PCR-EIA is a useful tool for the diagnosis of meningitis, especially when culture and LA are negative because of prior antibiotic treatment.     

pH-adjusted periocular anaesthesia for primary vitreoretinal surgery

PURPOSE: To evaluate the efficacy of pH-adjusted bupivacaine in conjunction with medial orbital periconal block (periocular anaesthesia). METHODS: Sixty consecutive patients undergoing primary vitreoretinal surgery were enrolled prospectively. RESULTS: Adequate anaesthesia and akinesia with no intraoperative supplementation was achieved in 53 eyes (88.3%). Factors influencing intraoperative supplementation were combined vitrectomy with scleral buckling (p = 0.005) and duration of surgery of more than 2 hours (p = 0.001). No ocular or systemic complication resulted. CONCLUSION: pH-adjusted periocular anaesthesia is safe and effective in patients undergoing primary vitreoretinal surgery.