Gastroesophageal reflux in very low birth weight infants: association with chronic lung disease and outcomes through 1 year of age.

OBJECTIVE: To analyze the association between chronic lung disease (CLD) and clinically diagnosed gastroesophageal reflux (GER) in very low birth weight (VLBW) infants, and between GER and outcomes at 1 year adjusted age. METHODS: A total of 375 consecutively born VLBW infants with CLD and 345 gestational age-matched controls were studied. Records were reviewed to ascertain which infants were diagnosed with GER (based on clinical suspicion or confirmatory tests) and which infants had delayed growth or development at 1 year adjusted age. RESULTS: Infants with CLD were treated for GER more frequently than controls (CLD: 27% versus controls: 9%; p < 0.0001). Among infants with CLD, those with and without GER were comparable in terms of the days on supplemental oxygen [124 (64 to 93) vs 121 (47 to 394)] and the proportion with cystic changes on chest radiograph (44% vs 47%). Comparing outcomes at 1 year for infants with and without GER, no differences were found in the rates of Bayley Mental Developmental and Psychomotor Developmental Indices of < 70, cerebral palsy, and measurements below the 10th percentile. CONCLUSION: Among VLBW infants, an association exists between CLD and GER, although this association might be due to greater diagnostic suspicion in infants with CLD. In VLBW infants, GER does not appear to increase the risk of delayed growth or development.     

Pneumothorax and other lung diseases: effect of altered resolution and edge enhancement on diagnosis with digitized radiographs

Prior studies have shown that pneumothorax is one of the more difficult entities to diagnose with digitized radiography. This study was designed to test whether increasing resolution from 1.25 to 2.5 line pairs per millimeter (lp/mm) and image processing (edge enhancement from unsharp masking) would increase accuracy and confidence in the diagnosis of pneumothorax, as well as normal cases and other forms of lung disease. Conventional radiographs were digitized with use of a laser reader and then reformatted as film hard copy. Eleven observers read 35 cases reformatted in three different ways (1.25 lp/mm, 2.5 lp/mm, 1.25 lp/mm unsharp mask). The images with finer resolution (2.5 lp/mm) and unsharp mask images were superior to those with coarser resolution (1.25 lp/mm) for the diagnosis of pneumothorax. There was no difference in diagnostic accuracy for normal patients. For abnormalities other than pneumothorax, the unsharp mask images were significantly worse. Confidence in the diagnosis of pneumothorax and other abnormalities was highest with the finest resolution (2.5 lp/mm).     

Bile duct stones: percutaneous transhepatic removal

Percutaneous transhepatic intervention for transduodenal removal of biliary stones was performed 38 times in 34 patients with obstructive jaundice, biliary colic, and cholangitis. The technique entailed the percutaneous transhepatic placement of a modified Dormia basket in the common duct with the flexible tip in the duodenum. The stones were passed into the duodenum and were crushed, or were crushed in the common duct and passed as fragments into the duodenum. In addition to the snare procedure, monooctanoin was used 18 times to dissolve remaining fragments of stone and sludge that could not be snared and passed into the duodenum. The average time for completion of the procedure was 10 days. There were no deaths from the procedure. The complication rate was 21%--probably no greater than would occur with surgery in a similar patient population. The procedure can be performed when endoscopic retrograde cholangiopancreatography and sphincterotomy with stone removal is technically impossible or refused, and in patients who have previously undergone choledochojejunostomy.     

赛拉嗪对麻醉大鼠海马CA1区乙酰胆碱含量的影响

应用乙酰胆碱选择性微电极技术,观察到小剂量赛拉嗪(2.0和6.0mg·kg^-1)可显著增加大鼠海马CA1区ACh的含量,而大剂量赛拉嗪(10.0mg·kg^-1)及咪唑克生(0.6mg·kg^-1)则作用相反。咪唑克生虽可明显拮抗赛拉嗪的作用,但海马CA₁区ACh的含量仍显著低于正常水平。在去兰斑核的大鼠上,赛拉嗪(2.0和6.0mg·kg^-1)及咪唑克生(0.6mg·kg^-1)分别对海马CA₁区ACh的含量具有减少和增加作用,且咪唑克生拮抗赛拉嗪的作用后,海马CA₁区ACh的含量基本恢复至正常水平。结果提示,赛拉嗪对麻醉大鼠海马CA₁区ACh含量呈双相性影响,咪唑可生虽能显著拮抗赛拉嗪的作用,但海马CA₁区ACh的含量仍明显低于正常水平,可能分别与赛拉嗪和咪唑克生降低或提高中枢NE能系统的功能有关。     

A PIL for every ill? Patient information leaflets (PILs): a review of past, present and future use

This article reviews the usefulness and importance of written information, specifically leaflets, being given to patients. Evidence suggesting how both patient and doctor may benefit from the giving of written information is reviewed. Identification of good practice relating to the content and readability of leaflets is discussed. An argument is put forward that the giving of written information is an under-utilized resource in contributing to improving patient outcomes but that this may be changing with the increasing use of patient leaflet databases. The advantages and disadvantages of computer- generated patient leaflets are discussed and desirable further areas of research on computer-generated leaflets are proposed.      

Neonatal treatment with 192 IgG-saporin produces long-term forebrain cholinergic deficits and reduces dendritic branching and spine density of neocortical pyramidal neurons

The role of basal forebrain-derived cholinergic afferents in the development of neocortex was studied in postnatal rats. Newborn rat pups received intraventricular injections of 192 IgG-saporin. Following survival periods ranging from 2 days to 6 months, the brains were processed to document the cholinergic lesion and to examine morphological consequences. Immunocytochemistry for choline acetyltransferase (ChAT) and in situ hybridization for ChAT mRNA demonstrate a loss of approximately 75% of the cholinergic neurons in the medial septum and nucleus of the diagonal band of Broca in the basal forebrain. In situ hybridization for glutamic acid decarboxylase mRNA reveals no loss of basal forebrain GABAergic neurons. Acetylcholinesterase histochemistry demonstrates a marked reduction of the cholinergic axons in neocortex. Cholinergic axons are reduced throughout the cortical layers; this reduction is more marked in medial than in lateral cortical areas. The thickness of neocortex is reduced by approximately 10%. Retrograde labeling of layer V cortico-collicular pyramidal cells reveals a reduction in cell body size and also a reduction in numbers of branches of apical dendrites. Spine densities on apical dendrites are reduced by approximately 20-25% in 192 IgG- saporin-treated cases; no change was detected in number of spines on basal dendrites. These results indicate a developmental or maintenance role for cholinergic afferents to cerebral cortical neurons.      

Oxygen supplementation during air travel in patients with chronic obstructive lung disease.

The objective of this study was to quantitate the effects of O2 supplementation by nasal cannula (NC) and Venturi mask (VM) on PaO2 in patients with chronic obstructive pulmonary disease (COPD) during acute hypobaric exposure, simulating a commercial jet aircraft cabin. We conducted a crossover intervention trial in which subjects served as their own controls in an ambulatory outpatient pulmonary disease service of a tertiary care military medical center and a hypobaric research facility. The subjects were a volunteer sample of 18 men with stable severe COPD, not requiring long-term O2 therapy, and uncomplicated by hypercapnea or cardiac disease. Mean age was 68 years, and mean FEV1 was 0.97 L (31.3 percent predicted). We exposed patients to conditions equivalent to 8,000 feet in a hypobaric chamber. Radial artery catheters provided blood samples at ground level and 8,000 feet. O2 was sequentially administered at 8,000 feet by NC at 4 L/min and 24 percent or 28 percent VM. We describe changes in blood gas data from baseline values and between interventions. O2 at 4 L/min NC flow at 8,000 feet caused PaO2 to increase from 47.4 +/- 6.3 mm Hg to 82.3 +/- 14 mm Hg (n = 18), an increase of 34.9 +/- 14.8 mm Hg. Supplementation of O2 by 24 percent VM caused PaO2 at 8,000 feet to increase by 12.7 +/- 3.8 mm Hg. Twenty-eight percent VM caused PaO2 at 8,000 feet to increase by 19.7 +/- 8.2 mm Hg. Changes in PaO2 with 4 L/min NC were greater than those with either VM. The increase with 28 percent VM was greater than that caused by 24 percent VM (p less than 0.05). Compared with ground level, 4 L/min NC increased mean PaO2 by 9.9 +/- 12.6 mm Hg; 24 percent and 28 percent VM did not cause mean PaO2 to increase above ground level values. We describe a range of capability of familiar O2 therapy devices to increase PaO2 to levels that will maintain tissue oxygenation of patients during acute altitude exposure.     

共轭方向法在HPLC流动相条件优化中的应用——麻黄碱、伪麻黄碱的分离

麻黄碱与伪麻黄碱是中药麻黄的主要有效成分,也是一对化学物理性质很相似的差向异构体。二者的结构只是构象不同,用色谱方法进行分离有一定的难度。目前已有在苯基和腈基键合固定相上进行HPLC分离的报道^(1,2)。本文成功地引入共轭方向法在μBondapak C₁₈色谱柱上对流动相组成进行了条件优化,优化后的色谱条件下麻黄碱与伪麻黄碱的分离情况令人满意。