Characterization of the cholesterol crystallization-promoting low- density particle isolated from human bile

BACKGROUND & AIMS: Biliary concanavalin A-binding glycoprotein (CABG) contains cholesterol crystallization-promoting activity that is not accounted for by the pronucleators that have been characterized in this fraction. The aim of this study was to isolate and characterize the missing activity. METHODS: Biliary glycoprotein was isolated using concanavalin A-Sepharose. Promoting activity in CABG was purified using density gradient ultracentrifugation. RESULTS: Activity in CABG separated into two fractions at low (1.08) and high (1.29) density, which showed different crystallization kinetics in a model bile. The high-density fraction had a late onset time (49.2 +/- 17.8 hours) but a high crystal growth rate (13.4 +/- 5.2 micrograms. mL-1.h-1). The low- density fraction had a rapid onset time (33.9 +/- 20.9 hours) but a slower growth rate (6.5 +/- 3.8 micrograms.mL-1 .h-1). The high-density fraction was not further characterized in this study. The low-density fraction contained solid particles consisting of lipid and very little protein, and the activity was fully pronase resistant. Delipidation of the low-density fraction removed all activity. CONCLUSIONS: A potent pronase-resistant nucleation-promoting activity was activated from human bile and characterized. The low-density fraction may be responsible for the rapid nucleation in bile from typical patients with fast-nucleating gallstones. (Gastroenterology 1996 Jun;110(6):1936-44)     

功能磁共振成像与弥散张量成像联合监测视觉通路异常在高压氧治疗前后的结构及功能变化

目的:联合应用血氧依赖功能磁共振成像(BOLD-fMRI)和弥散张量成像技术评价视觉通路异常高压氧患者在康复过程中脑功能和解剖结构的重组特点。方法:①临床资料:选择2006-01/2007-05解放军南京军区福州总医院收治的因视觉通路病变致单侧或双侧视觉障碍的16例患者为病变组,均接受2个标准大气压高压氧治疗3个疗程。以性别、年龄与病变组大致匹配的正常视力者12例作为正常对照组。②磁共振扫描及分析:两组以相同条件,采用黑白棋盘格变化刺激双眼,应用Signa xcite HD 1.5T双梯度16通道磁共振成像系统进行测试。BOLD-fMRI数据处理采用AFNI软件包进行,弥散张量成像应用日本东京大学影像计算和分析实验室开发的Volume-one 1.64下的dTV.II.R1软件进行数据处理。③观察指标:病变组高压氧干预前后BOLD-fMRI激活体数和弥散张量成像表现,并与正常对照组比较。结果:28例受试者均进入结果分析。①BOLD-fMRI激活体数值:病变组高压氧治疗前视皮质激活体数低于正常对照组(P<0.01),高压氧治疗后视皮质激活体数与正常对照组比较差异不显著(P>0.05),但高于高压氧治疗前(P<0.05)。②弥散张量成像示视放射部分各向异性值:病变组高压氧治疗前部分各向异性值低于正常对照组(P<0.05),高压氧治疗后与正常对照组比较差异不显著(P>0.05),且显著高于高压氧治疗前(P<0.05)。病变组中的6例视神经病变患者视放射显示完整,康复前后的视放射部分各向异性值与正常对照组比较无显著性差异(P>0.05),10例枕叶视中枢病变患者视放射纤维部分中断,视放射各向异性值低于视神经病变患者(P<0.05)。结论:BOLD-fMRI联合弥散张量成像能从功能和结构方面探讨视觉通路病变的发生、发展及康复过程,为脑功能的康复提供较为可靠的治疗依据。     

A simple monthly means chart system for monitoring sperm concentration

A simple, robust monthly means chart system for monitoring sperm concentration was developed and used in our andrology laboratory. The system relied on the central limit theorem to allow estimation of chart limits without resorting to data transformation procedures. Once the chart was drawn up, the arithmetic mean of sperm concentration was determined monthly and plotted. Monthly means which fell outside 2 SE from the baseline mean were investigated. Initial experience with this chart system suggests that it provides a simple and useful quality assurance method which should be applicable to other semen variables such as motility and sperm morphology.      

Radiologic evaluation of mass casualty victims: lessons from the Gander, Newfoundland, accident

This study describes the use of radiologic methods in the identification of 256 bodies after the crash of an airliner in Gander, Newfoundland. Two hundred thirty-one (90%) of the victims were identified positively with dental and/or fingerprint comparisons. Radiologic data confirmed identification in 29 of these victims. Seventeen bodies without dental or fingerprint identification were presumptively identified with a variety of data, which included radiologic characteristics in four cases. Eight bodies were identified with an exclusion matrix. Radiologic input was critical in two of these. The procedures described provide practical information for radiologists in a mass casualty disaster investigation.     

Which AO/OTA 31-A2 pertrochanteric fractures can be treated with a dynamic hip screw without developing a lateral wall fracture? A CT-based study

Purpose

To determine whether radiographic measurements derived from standard computed tomography (CT) evaluation can be used to predict likelihood of a peri-operative lateral femoral wall fracture in AO/OTA 31-A2 pertrochanteric fractures treated with a dynamic hip screw (DHS).

Methods

Fifty-one patients with AO/OTA 31-A2 classified pertrochanteric fractures were evaluated using a pre-operative CT scan of the pelvis with both hips. Dimensions of the lateral wall were calculated for each patient using four parameters: (1) height of the lateral wall above the vastus ridge; (2) circumference of the lateral wall 2 cm below the vastus ridge at an angle of 135°; this circumference was further divided into an anterior, lateral and posterior component; (3) cortical thickness at the centre of the lateral component of the lateral wall; and (4) cortical index. All patients were treated with a 135° DHS. Postoperative radiographs were assessed for lateral femoral wall fracture.

Results

Patients with a lateral wall fracture (17/51) had a smaller circumference (4.47 cm vs 5.44 cm p value?<0.001) as well as a lower height of the lateral femoral wall (1.37 cm vs 2.21 p value?<?0.001). Analysis of the three components of the circumference revealed a significant difference for the anterior component only and not for the lateral and posterior components. There was no statistical difference in the cortical thickness or cortical index in the two groups. The cutoff values for height of the lateral wall and anterior component were calculated using ROC curves and found to be 1.68 cm (AUC 0.918) and 2.10 cm (AUC 0.851) respectively.

Conclusion

AO/OTA 31-A2 pertrochanteric fractures with a lateral wall height of > 1.68 cm and an anterior component of > 2.10 cm in circumference are not likely to sustain a lateral wall fracture when treated with a DHS.

     

Science review: Searching for gene candidates in acute lung injury

Acute lung injury (ALI) is a complex and devastating illness, often occurring within the setting of sepsis, and carries an annual mortality rate of 30–50%. Although the genetic basis of ALI has not been fully established, an increasing body of evidence suggests that genetic predisposition contributes to disease susceptibility and severity. Significant difficulty exists, however, in defining the exact nature of these genetic factors, including large phenotypic variance, incomplete penetrance, complex gene–environment interactions, and strong potential for locus heterogeneity. We utilized the candidate gene approach and an ortholog gene database to provide relevant gene ontologies and insights into the genetic basis of ALI. We employed a Medline search of selected basic and clinical studies in the English literature and studies sponsored by the HopGene National Institutes of Health sponsored Program in Genomic Applications. Extensive gene expression profiling studies in animal models of ALI (rat, murine, canine), as well as in humans, were performed to identify potential candidate genes . We identified a number of candidate genes for ALI, with blood coagulation and inflammation gene ontologies being the most highly represented. The candidate gene approach coupled with extensive gene profiling and novel bioinformatics approaches is a valuable way to identify genes that are involved in ALI.     

Reduction of human immunodeficiency virus-infected cells from donor blood by leukocyte filtration

Several filters for leukocyte removal were evaluated in terms of their ability to reduce the cell-associated human immunodeficiency virus (HIV) load in units of blood either inoculated in vitro with lymphocytes from a chronically infected cell line or collected directly from seropositive donors. Filtration of the experimentally inoculated units of blood resulted in a 5.9 log 10 mean reduction (95% confidence interval:7.4-4.5) of tissue culture infectious units (TCIU) as assayed by end-point titration using the coculture assay. Filtration of the units of blood from anti-HIV positive donors lowered the infectivity by over 2 logs, as detected by the coculture and polymerase chain reaction (PCR) techniques. However, residual cell-associated virus was detected in the majority of experiments. Clinical studies are warranted to determine if leukocyte filtration of blood will reduce the risk of transfusion transmitted viral infections.