Influence of age on the reactivity of the BANA test among Brazilian children.

Three hundred and twenty samples of subgingival plaque were obtained from 80 caucasian girls, ranging from 10 to 13 years of age. The samples were analyzed to verify the influence of age upon colonization of the gingival sulcus by microorganisms potentially pathogenic to the periodontal tissues. The gingival and plaque status were evaluated through the gingival index (GI) and plaque index (PlI) and the microflora was assessed by the enzymatic method benzoyl-arginine-naphthylamide (BANA). The results of the BANA test were positive for 62.50% of the tested individuals and 40% of the examined sites. The influence of age was statistically significant on BANA reactivity, and the number of positive sites was greater at 11 (57.5%) than at 12 years (28.8%).     

Evidence for the presence of a type III secretion system in diffusely adhering Escherichia coli (DAEC).

Diffusely adhering Escherichia coli (E. coli) strains (DAEC) represent a potential cause of diarrhoea in infants, and the detection of type three secretion system (TTSS) genes in DAEC would substantiate their pathogenic nature. In this work, four isolates of DAEC, recovered from stools of diarrhoeic children, were analysed by PCR, in order to detect the presence of TTSS genes. Primers targeted to the escC, escJ, escN and escV, some of the most conserved TTSS genes in enteropathogenic and enterohaemorrhagic Escherichia coli (EPEC and EHEC), were used in order to verify the occurrence of homologous genes in our DAEC isolates. By this approach, we were able to characterise DNA fragments corresponding to putative escJ and escN genes in all DAEC isolates. Furthermore, DNA fragments homologous to the escC and escV genes were also amplified from all isolates. Besides the similarity found among the DAEC esc homologues with EPEC and EHEC esc genes, the nucleotide sequence analysis of the flanking regions of the amplified DNA fragments suggests that the putative DAEC esc genes are organised in the same manner as observed in EPEC and in EHEC strains. The results described here provide strong evidence for the presence of a TTSS in the DAEC strains analysed, implicating a pathogenic nature of these isolates.     

亚硒酸钠对顺铂致人体淋巴细胞增殖抑制的拮抗作用

目的 检测亚硒酸钠是否能够削弱或解除顺铂对植物血球凝激素(PHA)刺激的人体外周血淋巴细胞的增殖抑制。方法 用顺铂和亚硒酸钠单独或联合处理PHA刺激的人体外周血淋巴细胞，顺铂(0．05，0．20，0．50mg／L)在细胞培养24h时加入，亚硒酸钠(0．05mg／L)在不同处理中分别在细胞培养开始时加入或与顺铂同时加入；培养72h后检测转化淋巴细胞的有丝分裂指数。结果0．05mg/L亚硒酸钠在培养开始时加入，PHA刺激转化的淋巴细胞有丝分裂指数较对照增长42．8％(P＜0．05)，与顺铂同时加入，有丝分裂指数增长13．7％(P＞0．05)。0．05与0．20mg/L顺铂处理细胞，有丝分裂指数未发生显性改变，当顺铂剂量为0．50mg/L时，细胞有丝分裂指数较对照降低54．5％(P＜0．001)。亚硒酸钠预处理细胞可以解除0．50mg/L顺铂所致的细胞增殖抑制，使有丝分裂指数恢复正常，但亚硒酸钠与顺铂同时加入时，被顺铂抑制的有丝分裂指数只能部分提高。结论0．05mg/L亚硒酸钠单独作用于淋巴细胞可直接促进细胞增殖，与顺铂联合处理细胞时，可降低顺铂毒性，拮抗顺铂的抗增殖作用。亚硒酸钠在细胞培养开始时加入培养体系效果更佳。     

Antigenuria after immunization with Haemophilus influenzae oligosaccharide CRM197 conjugate (HbOC) vaccine

We tested the urine of 30 infants 6 weeks to 7 months of age after they received standard 10-micrograms (0.5-ml) doses of HbOC (HibTITER) Haemophilus influenzae b (Hib) conjugate vaccine for the presence of Hib antigenuria using a commercially available latex particle agglutination assay (Directigen). Urines were collected within 1 hour, from 1 to 3 hours, at 24 hours and at 3, 6 and 9 days after vaccine administration and reactions were quantitated from 0 to 3+. In contrast to previous studies in older children which showed little or no antigenuria following HbOC vaccination, our study shows that in infants intense Hib antigenuria is evident within 2 to 3 hours and persists 3 days after vaccine administration and that less intense antigenuria may be detected in some infants for several days. With efficacious vaccines now being used in 2- to 6-month-old infants, invasive Hib disease may soon be limited to infants of this age just before their seroconversion. It should be recognized that antigenuria occurs for several days after vaccination with Hib conjugate vaccines and that it could be erroneously interpreted as evidence of invasive Hib infection.     

Acetabular blood flow during Bernese periacetabular osteotomy: an intraoperative study using laser Doppler flowmetry.

BACKGROUND: The blood flow to the acetabular fragment is of some concern in juxtaarticular pelvic osteotomies used for the treatment of hip dysplasia. No direct measurements have determined the effect of the Bernese periacetabular osteotomy (PAO) on acetabular perfusion. METHODS: Acetabular perfusion was measured by means of laser Doppler flowmetry in 10 patients undergoing a PAO for symptomatic acetabular dysplasia. During the surgical procedure, the intraosseous high energy laser Doppler reliably depicts dynamic changes of small vessel blood flow. Measurements were performed after defined surgical steps to obtain sequential information on the blood perfusion of the acetabular fragment. RESULTS: After complete separation of the acetabular fragment, nine out of 10 patients had pulsatile signals, but the blood flow (BF) significantly decreased by 77%. Corrective positioning of the fragment induced no further drop of the BF signal but a loss of pulsatility in six patients. After a recovery period of about 30 min following preliminary fixation of the fragment, reestablishment of the pulsatile signal and an increase of the BF signal was seen. At termination of the surgical procedure, five out of eight patients, who could be followed throughout the whole procedure, showed a clear pulsatile signal in the supraacetabular area. Bleeding of the supraacetabular cancellous surface could be observed in all acetabula. CONCLUSION: Despite careful preservation of soft tissues during the surgical procedure, a significant reduction of the blood flow in the supraacetabular region has been observed. Nevertheless, a pulsatile signal in more than 60% of the fragments after fragment correction and an increasing signal during the recovery period showed ongoing blood perfusion indicating reversible changes in the measured supraacetabular area. All osteotomies healed within eight weeks without showing signs of necrosis during a minimum follow up of 1 year.     

Acute Leukemia in an Infant with Marfan's Syndrome: A Case Report

We describe a familial case of Marfan's syndrome with associated intrathoracic stomach detected during the neonatal period. The patient developed a primitive leukemia at 3 months of age. Acute leukemia in a patient with Marfan's syndrome has not previously been reported.