Dexamethasone potentiates in vitro blood-brain barrier recovery after primary blast injury by glucocorticoid receptor-mediated upregulation of ZO-1 tight junction protein

Owing to the frequent incidence of blast-induced traumatic brain injury (bTBI) in recent military conflicts, there is an urgent need to develop effective therapies for bTBI-related pathologies. Blood-brain barrier (BBB) breakdown has been reported to occur after primary blast exposure, making restoration of BBB function and integrity a promising therapeutic target. We tested the hypothesis that treatment with dexamethasone (DEX) after primary blast injury potentiates recovery of an in vitro BBB model consisting of mouse brain endothelial cells (bEnd.3). DEX treatment resulted in complete recovery of transendothelial electrical resistance and hydraulic conductivity 1 day after injury, compared with 3 days for vehicle-treated injured cultures. Administration of RU486 (mifepristone) inhibited effects of DEX, confirming that barrier restoration was mediated by glucocorticoid receptor signaling. Potentiated recovery with DEX treatment was accompanied by stronger zonula occludens (ZO)-1 tight junction immunostaining and expression, suggesting that increased ZO-1 expression was a structural correlate to BBB recovery after blast. Interestingly, augmented ZO-1 protein expression was associated with specific upregulation of the α⁺ isoform but not the α⁻ isoform. This is the first study to provide a mechanistic basis for potentiated functional recovery of an in vitro BBB model because of glucocorticoid treatment after primary blast injury.     

An intron in the thymidylate synthase gene of Bacillus bacteriophage beta 22: evidence for independent evolution of a gene, its group I intron, and the intron open reading frame.

The thymidylate synthase gene (thy) (EC 2.1.1.45) of Bacillus subtilis bacteriophage beta 22 has a self-splicing, group I intron inserted into a highly conserved region of the coding sequence. The intron is very similar to one that is inserted 21 bp further downstream in the homologous thymidylate synthase gene (td) of Escherichia coli bacteriophage T4. In contrast, the amino acid sequences of the bacteriophage thymidylate synthases are highly divergent. The beta 22 intron has a fragmentary open reading frame (ORF) that encodes a putative helix-turn-helix DNA-binding motif, similar to one at the carboxyl terminus of the homing endonuclease (I-TevI) encoded by the T4 td intron. The td ORF and the thy ORF fragments are inserted into different regions of their respective intron structures. These results suggest that the thymidylate synthase genes, their introns, and their respective intron-ORFs all have separate evolutionary histories and that the acquisition of the intron could not have occurred by a simple homing event.     

Results of the tension-free vaginal tape procedure for stress incontinence: Patient''s perspective

BACKGROUND: To evaluate the results of the tension-free vaginal tape procedure (TVT) from a patient's perspective. METHODS: Between May 1999 and January 2002, 90 patients underwent a TVT for genuine stress incontinence (GSI) and mixed incontinence. Prior to the procedure, GSI was confirmed by clinical examination and urodynamic studies. Results were then audited from patient notes and the same patients were sent questionnaires to examine results from a patient perspective. RESULTS: Overall response rate to the questionnaire was 70 (77%). The mean age of the patients was 50.4 years (range 31-83 years). Sixty-one patients had spinal anesthesia, seven had general anesthesia and two had local anesthesia. Mean hospital stay was 3.36 days (range 2-14 days) and mean period from the operation to the time of the survey and audit was 16.34 months (range 3-28; SD 6.92). Thirty-nine (56%) of the 70 patients who answered said that the operation had cured their incontinence, 16 (23%) had an improvement in their symptoms, 7 (10%) had worsening of their symptoms and 8 (11%) felt that the operation did not make any difference. The overall success rate according to the patients' perspective was 79%, whereas our audit showed an overall success rate of 86% (77% and 82%, respectively, when we compared only the 66 patients who had both notes and replies available for analysis). CONCLUSION: Although a patient's perception regarding the success of TVT tends to differ from that of a clinician, it was not found to be statistically significant (P = 0.22, McNemar test). The TVT is a very successful operation, but realistic cure rates should be offered to patients.     

Hodgkin disease: CT of the thymus

The computed tomography (CT) scans in two groups of patients with Hodgkin disease were reviewed to determine the frequency of thymic enlargement. In 50 CT scans from 50 patients with evidence of thoracic disease on CT scans who were examined for primary staging, the thymus was enlarged in 15 of 50 (30%). Fifty CT scans were obtained from 44 patients at the time of 50 separate episodes of known or suspected relapse. Relapse occurred in the mediastinum in 12 episodes, lung parenchyma in five, and both sites in one. Thymic enlargement thought to be due to involvement by disease was present in seven of 18 (38%). Mediastinal disease was associated with thymic enlargement in all but one patient in whom a thymic cyst developed after radiation therapy. Differentiation of thymic enlargement from enlarged superior mediastinal lymph nodes was easily made in all but two patients. Thymic enlargement in the absence of lymph node enlargement may indicate a different disease, since isolated Hodgkin disease of the thymus is uncommon. Primary thymic tumor should be considered initially, whereas after treatment, rebound hyperplasia of the thymus may be the cause of enlargement.     

Solid and papillary epithelial neoplasms of the pancreas: CT findings

Five female patients and one male patient with solid and papillary epithelial neoplasms of the pancreas were examined with computed tomography (CT). The mean age of the patients was 27 years (range, 13-46 years). All cases showed well-encapsulated, round or lobulated masses consisting of both cystic and solid areas. Cystic portions showed CT numbers that suggested hemorrhagic necrosis. There were no internal septations within the masses. In three tumors located in the head of the pancreas, dilatation of the biliary tree was absent or minimal, although the masses were large. Two tumors contained calcifications. One tumor demonstrated metastatic deposits in liver and lymph nodes. Metastatic masses appeared similar to the primary pancreatic mass. Solid and papillary neoplasm of the pancreas should be the primary diagnostic consideration when characteristic CT findings are detected in a young female patient.     

5'' flanking sequence and structure of a gene encoding rat 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase.

The synthesis and degradation of fructose 2,6-bisphosphate, a ubiquitous stimulator of glycolysis, are catalyzed by 6-phosphofructo-2-kinase (EC 2.7.1.105) and fructose-2,6-bisphosphatase (EC 3.1.3.46), respectively. In liver, these two activities belong to separate domains of the same 470-residue polypeptide. Various mRNAs have been described for this bifunctional enzyme, which is controlled by hormonal and metabolic signals. To understand the origin and regulation of these mRNAs, we have characterized rat genomic clones encoding the liver isozyme, which is regulated by cAMP-dependent protein kinase, and the muscle isozyme, which is not. We describe here a 55-kilobase gene that encodes these isozymes by alternative splicing from two promoters. Each of the putative promoters was sequenced over about 3 kilobases and found to include nucleotide motifs for binding regulatory factors. The two isozymes share the same 13 exons and differ only by the first exon that, in the liver but not in the muscle isozyme, contains the serine phosphorylated by cAMP-dependent protein kinase. The gene was assigned to the X chromosome. An analysis of the exon limits of 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase in relation to its functional domains and to its similarity with other proteins plus its G + C content at the third codon position suggests that this gene originates from several fusion events.     

Variable selection under multiple imputation using the bootstrap in a prognostic study

Background  

Missing data is a challenging problem in many prognostic studies. Multiple imputation (MI) accounts for imputation uncertainty that allows for adequate statistical testing. We developed and tested a methodology combining MI with bootstrapping techniques for studying prognostic variable selection.     

The skin,tongue, and brain as favorable organs for hog cholera diagnosis by immunofluorescence

Summary Hog cholera virus antigens were found densely distributed in skin and tongue of pigs experimentally infected with hog cholera virus. The finding described here warrants the usage of ear biopsies for hog cholera diagnosis on a herd basis.     

Fatal avian influenza A (H5N1) in a child presenting with diarrhea followed by coma

In southern Vietnam, a four-year-old boy presented with severe diarrhea, followed by seizures, coma, and death. The cerebrospinal fluid contained 1 white cell per cubic millimeter, normal glucose levels, and increased levels of protein (0.81 g per liter). The diagnosis of avian influenza A (H5N1) was established by isolation of the virus from cerebrospinal fluid, fecal, throat, and serum specimens. The patient's nine-year-old sister had died from a similar syndrome two weeks earlier. In both siblings, the clinical diagnosis was acute encephalitis. Neither patient had respiratory symptoms at presentation. These cases suggest that the spectrum of influenza H5N1 is wider than previously thought.