The enhanced virulence of very virulent infectious bursal disease virus is partly determined by its B-segment

There is a remarkable difference in virulence of infectious bursal disease virus (IBDV) strains ranging from sub-clinical infections for serotype 2 and cell culture adapted serotype 1 strains, to 100% mortality for very virulent serotype 1 strains in young SPF chickens. It is known that cell culture adaptation related attenuation is determined by distinct mutations in the hypervariable region of the VP2 outer capsid protein, encoded on the A-segment. Amino acid mutations in the hypervariable VP2 region however, offer no explanation for the difference in virulence of classical and very virulent serotype 1 strains. Here we show by in vitro and in vivo analysis of rescued segment reassorted IBDVs that virulence factors are not only located on the A-segment, but on the RNA Dependent RNA Polymerase (VP1) encoding B-segment as well. Insight into the virulence factors of very virulent IBDV will contribute to the improvement of live IBDV vaccines

Structure of human chitotriosidase - Implications for specific inhibitor design and function of mammalian chitinase-like lectins

FWN – Publicaties zonder aanstelling Universiteit Leide

Effects of Cooling During Exercise on Thermoregulatory Responses of Men With Paraplegia.

BACKGROUND: People with spinal cord injury (SCI) have an altered afferent input to the thermoregulatory center, resulting in a reduced efferent response (vasomotor control and sweating capacity) below the level of the lesion. Consequently, core body temperature rises more rapidly during exercise in individuals with SCI compared with people who are able-bodied. Cooling strategies may reduce the thermophysiological strain in SCI. OBJECTIVE: The aim of this study was to examine the effects of a cooling vest on the core body temperature response of people with a thoracic SCI during submaximal exercise. METHODS: Ten men (mean age=44 years, SD=11) with a thoracic lesion (T4-T5 or below) participated in this randomized crossover study. Participants performed two 45-minute exercise bouts at 50% maximal workload (ambient temperature 25°C), with participants randomized to a group wearing a cooling vest or a group wearing no vest (separate days). Core body temperature and skin temperature were continuously measured, and thermal sensation was assessed every 3 minutes. RESULTS: Exercise resulted in an increased core body temperature, skin temperature, and thermal sensation, whereas cooling did not affect core body temperature. The cooling vest effectively decreased skin temperature, increased the core-to-trunk skin temperature gradient, and tended to lower thermal sensation compared with the control condition. LIMITATIONS: The lack of differences in core body temperature among conditions may be a result of the relative moderate ambient temperature in which the exercise was performed. CONCLUSIONS: Despite effectively lowering skin temperature and increasing the core-to-trunk skin temperature gradient, there was no impact of the cooling vest on the exercise-induced increase in core body temperature in men with low thoracic SCI

Expression, secretion and antigenic variation of bacterial S-layer proteins.

The function of the S-layer, a regularly arranged structure on the outside of numerous bacteria, appears to be different for bacteria living in different environments. Almost no similarity exists between the primary sequences of S-proteins, although their amino acid composition is comparable. S-protein production is directed by single or multiple promoters in fron of the S-protein gene, yielding stable mRNAs. Most bacteria secrete S-proteins via the general secretory pathway (GSP). Translocation of S-protein across the outer membrane of Gram-negative bacteria sometimes occurs by S-protein-specific branches of the GSP. O-polysaccharide side-chains of the lipopolysaccharide component of the cell wall of Gram-negative bacteria appear to function as receptors for attachment of the S-layer. Silent S-protein genes have been found in Campylobacter fetus and Lactobaccillus acidophilus. These silent genes are placed in the expression site in a fraction of the bacterial population via inversiion of a chromosomal segment

Avaliação funcional dos pacientes submetidos ao desbridamento artroscópico para tratamento das rupturas extensas e irreparáveis do manguito rotador Functional evaluation of patients who have undergone arthroscopic debridement to treat massive and irreparable tears of the rotator cuff

OBJETIVO: Avaliar os resultados dos pacientes submetidos ao desbridamento artroscópico das lesões extensas e irreparáveis do manguito rotador. Métodos: Foram operados 27 pacientes no período de 2003 a 2007, sendo avaliados 22 desses. O procedimento cirúrgico consistiu de desbridamento artroscópico do coto dos tendões envolvidos, bursectomia, remoção do osteófito acromial e, eventualmente, tenotomia do bíceps e tuberoplastia. RESULTADOS: No pré-operatório todos apresentavam envolvimento dos tendões do supra e infraespinal. Na avaliação pós-operatória, 14 pacientes estavam com o redondo menor íntegro e três com ruptura parcial do subescapular. Houve melhora dos critérios da UCLA de 15 no pré-operatório para 31 no pós. Não houve melhora de força muscular, porém ocorreu redução da dor. Conclusão: Desbridamento artroscópico é um procedimento indicado para pacientes idosos com ruptura irreparável do manguito rotador, que tenham boa ADM, baixa demanda funcional e com o principal objetivo de reduzir a dor.<br>OBJECTIVE: To evaluate the results in patients who have undergone arthroscopic debridement of massive and irreparable injury of the rotator cuff. METHODS: 27 patients were operated in the period from 2003 to 2007, during which 22 of them were evaluated. The procedure used consisted of arthroscopic debridement of the related tendons of the residual limb, bursectomy, acromial osteophyte removal, and eventually, biceps tenotomy and tuberoplasty. RESULTS: All patients showed involvement of the supraspinatus and infraspinatus tendons in the preoperative stage. In the postoperative evaluation, 14 patients had an teres minor muscle, and 3 had partial tears of the subscapularis tendon. There was an improvement in the UCLA criteria from 15 preoperatively to 31 postoperatively. There was no improvement in muscular strength, but there was a reduction in the pain. CONCLUSION: Arthroscopic debridement is a recommended procedure for elderly people with irreparable rotator cuff rupture, good ROM, low functional demand, and whose main objective is to diminish pain

Generation of full-length cDNA of the two genomic dsRNA segments of infectious bursal disease virus

To determine the complete nucleotide sequence of Infectious Bursal Disease virus (IBDV) isolates, an efficient method was developed to generate full-length cDNA of both the genomic A- and B-segments. Reverse transcription was carried out at the highest possible temperature (50°C) for the reverse transcriptase enzyme, and the single stranded cDNA was subsequently amplified by using an optimized PCR. The double stranded, full-length cDNA was efficiently cloned into a high copy number plasmid. Our results show that the entire cDNA of both the A- and B-segment of a classical attenuated isolate (CEF94), and a very virulent field isolate (D6948), can be cloned. The method will simplify greatly the procedure to generate full-length cDNA and determine the nucleotide sequence of the entire genome of IBDV isolates