Quantitation of HBsAg predicts response to entecavir therapy in HBV genotype C patients

AIM:To analysis the factors that predict the response to entecavir therapy in chronic hepatitis patients with hepatitis B virus (HBV) genotype C. METHODS:Fifty patients [hepatitis B e antigen (HBeAg)-negative:HBeAg-positive = 26:24] with HBV genotype C, who received nave entecavir therapy for 2 years, were analyzed. Patients who showed HBV DNA levels ≥ 3.0 log viral copies/mL after 2 years of entecavir therapy were designated as slow-responders, while those that showed 3.0 log copies/mL were termed rapid- responders. Quantitative hepatitis B surface antigen (HBsAg) levels (qHBsAg) were determined by the Architect HBsAg QT immunoassay. Hepatitis B core-related antigen was detected by enzyme immunoassay. Pre-C and Core promoter mutations were determined using by polymerase chain reaction (PCR). Drug-resistance mutations were detected by the PCR-Invader method. RESULTS:At year 2, HBV DNA levels in all patients in the HBeAg-negative group were 3.0 log copies/mL. In contrast, in the HBeAg-positive group, 41.7% were slow-responders, while 58.3% were rapid-responders. No entecavir-resistant mutants were detected in the slow-responders. When the pretreatment factors were compared between the slow-and rapid-responders; the median qHBsAg in the slow-responders was 4.57 log IU/mL, compared with 3.63 log IU/mL in the rapid-responders (P 0.01). When the pretreatment factors predictive of HBV DNA-negative status at year 2 in all 50 patients were analyzed, HBeAg-negative status, low HBV DNA levels, and low qHBsAg levels were significant (P 0.01). Multivariate analysis revealed that the low qHBsAg level was the most significant predictive factor (P = 0.03). CONCLUSION:Quantitation of HBsAg could be a useful indicator to predict response to entecavir therapy.     

电针对产后轻中度压力性尿失禁合并盆腔器官脱垂疗效观察

目的观察电针治疗产后轻中度压力性尿失禁合并盆腔器官脱垂的临床疗效。方法采用随机数字表法将68例产后轻中度压力性尿失禁合并盆腔器官脱垂的患者分为观察组和对照组,每组34例。观察组取百会、中脘、气海、中极、水道、子宫、足三里、三阴交,子宫、水道连接电针仪;肾俞、次髎、会阳,次髎、会阳连接电针仪;两组穴位隔日交替使用。对照组采用生物反馈电刺激治疗。每周3次,连续治疗6周,并于治疗前、治疗后采用盆底肌力检测、1 h尿垫试验、盆腔器官脱垂定量(pelvic organ prolapse quantitation,POP-Q)分度法进行疗效评价。结果观察组治疗后盆底肌持续收缩力、快速收缩力均高于对照组(P<0.05),且观察组治疗后与治疗前肌力差值大于对照组(P<0.01);观察组治疗后1 h尿垫试验漏尿量小于对照组(P<0.05),且观察组治疗前后漏尿量差值大于对照组(P<0.01);两组治疗后POP-Q分度均较治疗前降低(P<0.01),且两组间比较差异有统计学意义(P<0.05)。结论电针治疗产后轻中度压力性尿失禁合并盆腔器官脱垂,有助于提高盆底肌收缩力,在改善漏尿量及盆腔器官脱垂程度方面存在优势。     

Performance of a completely automated system for monitoring CMV DNA in plasma

BackgroundCompletely automated systems for monitoring CMV-DNA in plasma samples are now available.ObjectivesEvaluate analytical and clinical performances of the VERIS™/MDx System CMV Assay^®.Study designAnalytical performance was assessed using quantified quality controls. Clinical performance was assessed by comparison with the COBAS^® Ampliprep™/COBAS^® Taqman CMV test using 169 plasma samples that had tested positive with the in-house technique in whole blood.ResultsThe specificity of the VERIS™/MDx System CMV Assay^® was 99% [CI 95%: 97.7–100]. Intra-assay reproducibilities were 0.03, 0.04, 0.05 and 0.04 log₁₀ IU/ml (means 2.78, 3.70, 4.64 and 5.60 log₁₀ IU/ml) for expected values of 2.70, 3.70, 4.70 and 5.70 log₁₀ IU/ml. The inter-assay reproducibilities were 0.12 and 0.08 (means 6.30 and 2.85 log₁₀ IU/ml) for expected values of 6.28 and 2.80 log₁₀ IU/ml. The lower limit of detection was 14.6 IU/ml, and the assay was linear from 2.34 to 5.58 log₁₀ IU/ml. The results for the positive samples were concordant (r = 0.71, p < 0.0001; slope of Deming regression 0.79 [CI 95%: 0.56–1.57] and y-intercept 0.79 [CI 95%: 0.63–0.95]). The VERIS™/MDx System CMV Assay^® detected 18 more positive samples than did the COBAS^® Ampliprep™/COBAS^® Taqman CMV test and the mean virus load were higher (0.41 log₁₀ IU/ml). Patient monitoring on 68 samples collected from 17 immunosuppressed patients showed similar trends between the two assays. As secondary question, virus loads detected by the VERIS™/MDx System CMV Assay^® were compared to those of the in-house procedure on whole blood. The results were similar between the two assays (−0.09 log₁₀ IU/ml) as were the patient monitoring trends.ConclusionThe performances of the VERIS™/MDx System CMV Assay^® facilitated its routine use in monitoring CMV-DNA loads in plasma samples.     

Low power method for estimating the magnetization transfer bound-pool macromolecular fraction

We present a practical method to estimate the magnetization transfer (MT) bound-pool fraction (M^b₀). The method is based on a first-order approximation of the saturation equation and allows an in vivo estimate of M^b₀, previously estimated only in vitro and requiring multiple (on the order of 10²) measurements. This method requires one saturation measurement, a T1 estimate, an accurate value for input power, and uses to advantage the low power limitations of clinical scanners. The approximation is shown to be feasible in expected tissue parameter ranges using simulations. Unlike the phenomenologic magnetization transfer ratio (MTR), M^b₀ is a true tissue parameter representing the semisolid proton concentration involved in saturation transfer, allowing comparability of MT effect independent of input power, off-resonance frequency, or equipment.     

应用Digoxigenin标记探针定量检测血清HBV DNA

本文报道采用非同位素Ｄｉｇｏｘｉｇｅｎｉｎ标记探针定量检测血清ＨＢＶ ＤＮＡ。显色膜经空气干燥，液体石蜡透明处理后，即可置酶联免疫检测仪上测定各斑点的光密度值，液长６３０ｎｍ。结果发现已各含量的ＨＢＶ ＤＮＡ在２－５００ｐｇ／样点范围内与其相应的ＯＤ值有着良好的线性关系。标本测得ＯＤ值后，便可知其含量，该法重复性试验试验结果良好，１１份ＨＢＶ ＤＮＡ阳性的血清经定量测定，其ＨＢＶ ＤＮＡ含量在２０     

Gastroesophageal reflux scintigraphy with radioactive capsules — a new technique for detection and quantitation of reflux

A new technique for performing quantitative gastroesophageal scintigraphy has been described. The method involves administration of radioactivity in capsule form into the stomach; the isotope is released after dissolution of the capsule. The mean time of onset of capsule breakage was 3.3 min (range 2–5 min) and complete dissolution occurred by 6.0 min (range 5–8 min). The appearance of isotope activity in the oesophagus by means of cine scintigraphy was quantified by PDP 11/34 computer (Gamma-11) in terms of percentage of gastroesophageal reflux (GER). In 15 healthy subjects, the percentage of reflux (mean ±S.D.) in the lower, middle and upper oesophagus was found to be 1.25±0.67, 0.26±0.23 and 0.02±0.04 respectively. We have studied 52 patients using this technique, and results are encouraging.     

Quantitative measurements with localized 1H MR spectroscopy in children with Canavan's disease

Canavan's disease is an autosomal recessive hereditary leukodystrophy resulting from deficiency of the enzyme aspartoacylase. Two children suffering from this metabolic brain disease were examined using image-guided localized proton spectroscopy. The absolute concentrations of metabolites were determined. These data demonstrate, for the first time, that the well known increase of the N-Acetylaspartic acid (NAA)/Cho ratio in this disease may be not only due to a reduction of choline-containing compounds in brain tissue but, at least in specific cases, also due to an increase of the NAA concentration, which is a result of the enzyme defect.     

Quantitative evaluation of myocardial single-photon emission tomographic imaging: application to the measurement of perfusion defect size and severity

A new method is described for precise quantitative analysis of the relative three-dimensional distribution of myocardial tracers. The system uses a 360° elliptical sampling of radial slices to create activity profiles. These are then positioned onto a common centre at the same angular coordinates as the corresponding radial slice reconstruction planes to generate a two-dimensional polar summary display. Abnormal distribution is then identified by automatic comparison of the patient polar map with the threshold of a normal database defined on a pixel by pixel basis as the normal mean –2.5 SD. Our stress and rest databases currently comprise 34 and 24 studies for sestamibi and tetrofosmin respectively. The present method differs from currently available software in two major respects. First, radial slices are used rather than short-axis slices to minimize operator intervention and to allow quantitative evaluation of the left ventricle volume independent of the heart size and without truncation, in particular near the apex and at the base. This sampling scheme also results in a more homogeneous and sampling-independent partial volume effect. Secondly, quantitative analysis is improved by calculating perfusion defect severity, extent and size in a precise manner. Severity is evaluated relative to a standardized background measurement and to the mean normal value rather than to the threshold value. This parameter was underestimated up to a defect extent of 32 cm² in our phantom studies. Calculation of defect extent takes into account the surface distortion resulting from planar projection by using pixel by pixel weighted factors but it is otherwise overestimated as a result of the limited resolution of the imaging system. Integrating defect severity and extent, our hypoperfusion index appeared to accurately estimate the true defect size in our phantom model (r=0.993). The reproducibility of analysis was 6.24% in phantom studies and 3.10% in patient studies including repeated acquisitions. Applied to a well-documented population of 80 patients, this method resulted in an 86% sensitivity and a 78% specificity for overall coronary artery disease detection with reference to the angiographic data.     

Quantitation of μ mRNA byin situ hybridization reveals a correlation between B-maturation associated antigens and IgM gene activation in acute lymphatic leukemias

Acute lymphatic leukemias, expressing the common acute leukemia antigen were investigated for expression of early T- and B-cell associated markers and the activation of the gene for the heavy chain of the immunoglobulin M. The gene activation as determined by quantification of the μ mRNA with a fluorochrome labeled gene probein situ in individual cells showed a wide spectrum of positivity which was correlated to increasing expression of B-maturation markers. There was also a correlation between the amount of cellular immunoglobulin as determined by immunofluorimetry.     

Effects of non-linear flow and spatial orientation on technetium-99m hexamethylpropylene amine oxime single-photon emission tomography

The effects of two post-acquisition corrections on the visual and quantitative analysis of technetium-99m hexamethylpropylene amine oxime (HMPAO) single-photon emission tomography (SPET) were determined. The corrections were for: (1) the improper spatial orientation of the patient data sets, and (2) the non-linear uptake of HMPAO across the blood-brain barrier. Reorienting the SPET image data sets removed observers' uncertainty in assessment caused by suspected head tilt; however, it increased their uncertainty due to perceived subtle perfusion deficits. Applying the correction to compensate for the decrease in uptake of HMPAO in high-flow regions resulted in an increase in the number of positive assessments. In a study involving 30 patient studies, intea-observer reliability increased from 62% to 83% (average of two observers) after applying both of the corrections, while inter-observer reliability improved from 62% to 81%. Quantitative methods of analysing the images are also affected by the corrections. In an ROI-based classification scheme, the quantitative assessments of more than one-half of the images are affected by the two corrections. These results need to be considered when comparing both quantitative and visual results from different studies in which the corrections may or may not have been applied.