Iatrogenic epithelial change caused by endotracheal intubation of neonates

Tracheae of 20 neonates were obtained at postmortem examination. All neonates had been intubated for between 4 h and 105 days. The tracheal epithelial lining was examined by both light and scanning electron microscopy. Five tracheae which had never been intubated served as controls. All of these showed ciliation throughout their length. Those neonates who had been intubated showed epithelial change which ranged from a simple deciliation to a full stratified squamous epithelium. The degree of change was broadly related to the duration of intubation.     

Emergency free flaps to the type IIIC tibial fracture

Type IIIC tibial fractures are complex injuries involving extensive bone and soft-tissue devascularization that result in a high percentage of complications and ultimate amputation. An emergency free flap transfer not only may salvage the limb but also may improve the aesthetic and functional results of reconstruction by placing the injured structures in a well-vascularized bed. Two cases of type IIIC tibial fracture were treated in this manner, and we present our experience with a 30-month follow-up of one patient and a 6-month follow-up of another patient.     

Nucleotide changes around the splicing acceptor of intron 24 in the factor VIII gene and its impact on splicing.

Nucleotide 6724 of the factor VIII gene harbors a polymorphism of low frequency. A report from Taiwan claimed that 97.9% of the 83 alleles examined were of the A nucleotide at this position, which is quite different to the data from Western populations. Furthermore, this nucleotide is the start of exon 25, located in juxtaposition to the splicing acceptor of intron 24. We wonder if the nucleotide change at this location might have any effect on the splicing process of pre-mRNA. Using genomic DNA with direct sequencing of the polymerase chain reaction-amplified intron 24/exon 25 junction site, we found that 59 of the 60 patient samples were of the GTG sequence at nucleotides 6724-6726. The polymorphism is similar between populations in Taiwan and Western countries. The sequence of intron 24 around the splicing acceptor was always TCCAACTCTATTGCCCTCAG (-20 to -1), except for one hemophiliac patient who had a mutation in which the absolute consensus AG doublet of the intron 24 splicing acceptor changed to the AA dinucleotide. Owing to the mutation, exon 24 was erroneously spliced to exon 26, and exon 25 was skipped. This finding further testifies to the importance of the invariant AG dinucleotide in the example of the factor VIII gene.     

The growth of meta-analytic literature from 1980 to 1993

A search of the literature was undertaken to estimate the number of meta-analytic studies that have been published in the social and health sciences to date. Altogether, 1,874 published quantitative reviews were located by the end of 1994: 892 in the health sciences, 982 in the social sciences. Trends from 1980 to 1993 indicate that, while the social sciences embraced the technique earlier, health researchers are now publishing almost twice as many meta-analyses as their social science colleagues.     

云南山楂叶化学成分的研究

目的：研究云南山楂叶化学成分。方法：云南山楂叶分别经乙醇和水提取，聚酰胺柱和硅胶柱层析，光谱分析鉴定。结果：分离鉴定了６个化合物，为芦丁，金丝桃甙，牡荆素，熊果酸，胡萝卜甙及二十九烷醇。结论：均为首次从云南山楂叶中分得。     

Human papillomavirus 16 DNA in NIH3T3 cells transformed by colonic cancer cellular DNA.

Human papillomavirus (HPV) 16 DNA is closely associated with human cancers. It has been identified as an aetiological agent in cervical cancers and, recently, in colonic neoplasms. To further understand the role of HPV 16 DNA in colorectal carcinogenesis, NIH3T3 cells were transformed with high molecular weight DNA from colonic cancer cells and the expression of HPV 16 DNA detected. Both human Alu and HPV 16 DNA sequences were found in the type II foci of CC-M2T cells by Southern blot hybridisation. Additionally, 100% tumorigenicity in nude mice was seen. This study shows the transfection of HPV DNA from colonic cancers into NIH3T3 mouse cells and suggests that HPV type 16 might be associated with the malignant transformation of colonic cells.     

Effects of beta-blocker therapy on ventilatory responses to exercise in patients with heart failure

BACKGROUND: Ventilatory efficiency is the increase in ventilation relative to carbon dioxide production during exercise. Congestive heart failure (CHF) is associated with decreased ventilatory efficiency. beta-blockers improve hemodynamics, prolong survival, and improve functional class in patients with CHF, though peak exercise performance may not improve. We hypothesized beta-blockers increase ventilatory efficiency in patients with CHF. METHODS AND RESULTS: The study group comprised 614 subjects with left ventricular ejection fraction < or = 40% referred for cardiopulmonary exercise testing. Clinical and exercise data were reviewed and recorded. For comparison, subjects were divided into those treated with beta-blockers (n = 195) and those not treated (n = 419). Subjects on beta-blockers had lower minute ventilation (12 +/- 4 versus 14 +/- 4 L/min, P < .001) at rest, which remained lower during submaximal and maximal exercise, by 4 and 6 L/min, respectively (P = .001). Ventilatory efficiency was increased in subjects treated with beta-blockers at submaximal (32 +/- 6 versus 34 +/- 7, P = .002) and maximal (34 +/- 7 versus 37 +/- 10, P = .005) exercise. Differences between treatment subgroups remained significant by covariate analysis; beta-blockers were also independently associated with decreased minute ventilation by multiple regression. CONCLUSION: Beta-blockers may be associated with increased ventilatory efficiency in CHF patients, which may contribute to improved functional class and quality of life.