Genotyping of Chlamydia trachomatis in Urine Specimens Will Facilitate Large Epidemiological Studies

The serovars of Chlamydia trachomatis-positive urine specimens (n = 81; as detected by PCR and ligase chain reaction) were successfully analyzed in 94% of cases by omp1 PCR-based RFLP analysis. The use of urine specimens and this simple and sensitive typing method will greatly facilitate epidemiological studies of C. trachomatis serovar distribution in asymptomatic C. trachomatis infections in both females and males.     

Postinjection transmission scanning in myocardial 18F-FDG PET studies using both filtered backprojection and iterative reconstruction.

The aim of the present study was to evaluate the effect of postinjection transmission scanning (Post-Tx) on both the qualitative interpretation and the quantitative analysis of cardiac (18)F-FDG PET images. Furthermore, the accuracy of 2 different methods to correct for emission contamination was studied. An additional aim of this study was to compare images reconstructed with both standard filtered backprojection (FBP) and an iterative reconstruction algorithm (ordered-subset maximization expectation [OSEM]). METHODS: Sixteen patients underwent dynamic (18)F-FDG imaging. Both before injection of (18)F-FDG and after completing the emission scan, a 10-min transmission scan was performed (Pre-Tx and Post-Tx, respectively). Images were reconstructed using both FBP and OSEM. The emission study reconstructed with Pre-Tx was considered to be the gold standard. Emission studies were also reconstructed with Post-Tx, with and without correction for emission contamination. Correction for emission contamination was performed with either transmission image segmentation (TIS) or by estimating the emission bias from the last emission frame (dwell profile [DP] method). All images were then compared by calculating ratios of (18)F-FDG activity between corresponding myocardial segments in each patient. Furthermore, qualitative grading of (18)F-FDG uptake was compared between the studies. RESULTS: The mean ratio of (18)F-FDG activity between segments from FBP-Post and FBP-Pre was 0.78 +/- 0.08. When TIS and DP were used, the mean ratios were 0.80 +/- 0.07 and 0.94 +/- 0.06, respectively. The use of OSEM resulted in, on average, 2% lower values for (18)F-FDG activity as compared with FBP. The mean normalized (18)F-FDG uptake was higher in FBP-Post, especially in segments with decreased (18)F-FDG activity. Only in the case of DP were no significant differences observed as compared with FBP-Pre. In general, qualitative analysis of the images showed that the agreement between the reconstruction methods was comparable with the reproducibility of FBP-Pre. CONCLUSION: Post-Tx for attenuation correction in cardiac (18)F-FDG PET scans resulted in substantial underestimation of (18)F-FDG activity. More accurate results were obtained with correction for emission contamination using DP. Differences in visual assessment of (18)F-FDG images were small. Finally, iterative reconstruction could be used as an alternative to FBP in static (18)F-FDG imaging of the heart.     

低脉压与晚期慢性心衰患者利钠肽和死亡率升高独立相关

目的:脉压(PP)升高一贯用来预测有心血管疾病危险患者和轻度慢性心衰(CH F)患者的心血管疾病发生率和死亡率增高。相反,PP降低与急性失代偿性心衰患者死亡率升高相关。然而,尚不清楚PP对于晚期CH F患者的预测价值。方法和结果:采用Cox比例风险回归分析研究了1901例N YH A III或IV级CH F患者(平均年龄65岁,平均射血分数26%)的资料,经校正其他危险因素后,分析PP对死亡率的影响。检测了1个亚组患者的利钠肽水平。多元Cox回归分析表明,PP降低与死亡率增高相关(每增加10m m H g的H R为0.91,95%CI0.93～0.99),这一相关性独立于平均…     

Microvascular function in viable myocardium after chronic infarction does not influence fractional flow reserve measurements.

Fractional flow reserve (FFR) is an index of coronary stenosis severity. FFR is the ratio of hyperemic myocardial flow in the stenotic area to maximal flow in that same territory without stenosis and can be measured with a pressure wire. In patients with prior infarction, measuring FFR in infarct-related arteries may be different for 2 reasons: a smaller mass of viable myocardium depending on the stenotic infarct-related artery and greater microvascular resistance in the infarcted area than in the reference area. When microvascular resistance does not differ between the infarcted and the reference areas, FFR should equal relative flow reserve (RFR). RFR is the ratio of myocardial blood flow in the stenotic area to blood flow in a normally perfused reference area, at maximal hyperemia. H(2)(15)O PET measures myocardial flow within only the viable areas of an infarct and can be used to measure RFR. The present study assessed in patients with chronic myocardial infarction whether microvascular resistance in the infarct is different from that in the reference area. Therefore, the correlation between FFR and RFR using H(2)(15)O PET was studied. METHODS: In the catheterization laboratory, FFR was measured in the infarct-related artery and a reference coronary artery. The H(2)(15)O PET study and FFR measurements were performed on the same day in 22 patients. RESULTS: In 27 patients, the mean interval between the PET study and infarction was 3.3 y. Most patients had an anterior infarction, and the mean ejection fraction was 44%. The mean FFR and RFR values were 0.75 +/- 0.16 and 0.74 +/- 0.18, respectively. A significant correlation (r = 0.81; P < 0.0001) was found between FFR and RFR. The linear regression line was close to the line of identity. CONCLUSION: In patients with chronic myocardial infarction and a reduced ejection fraction, a good correlation was found between FFR measurements in the infarct-related artery and RFR. Because the linear regression line between FFR and RFR was close to the line of identity, one can conclude that microvascular resistance in the viable myocardium does not differ from that in the reference area.     

Quantification of dopamine transporter binding using [18F]FP-beta-CIT and positron emission tomography.

The purpose of this study was to compare different kinetic and semi-quantitative methods for analysing human [18F]FP-beta-CIT studies: plasma input models, simplified (SRTM) and full (FRTM) reference tissue models, standard uptake values (SUV) and SUV ratios (SUVr). Both simulations and clinical evaluations were performed to determine the effects of noise, scan duration and blood volume on Akaike model selection, and on precision and accuracy of estimated parameters. For typical noise levels (COV approximately 2.5%) and scan durations (<90 mins), simulations provided poor fits (Akaike criterion) in case of reversible plasma input models showing a relatively high number of outliers compared with the two-tissue irreversible model. Reference tissue models provided more reliable fits, which were nearly independent of noise and scan duration. For clinical data, two tissue irreversible and reversible plasma input models fitted striatum curves equally well (Akaike criterion). BP with plasma input models were less precise and contained more outliers than BP obtained with SRTM or FRTM. Among all methods tested, SRTM showed the highest contrast between patients and controls. When differentiating between patients and controls, SUVr performed almost equally well as SRTM, although contrast between striatum and background was lower. In conclusion, SRTM provided BP estimates with the highest precision and accuracy. Moreover, SRTM provided good contrast between patients and controls, and between striatum and background. SRTM is therefore the method of choice for quantitative [18F]FP-beta-CIT studies. SUVr might be an alternative for larger clinical trials.     

A phase I study of a new 5HT3-receptor antagonist,BRL43694A,an agent for the prevention of chemotherapy-induced nausea and vomiting

Summary In a phase I study of BRL43694A, a 5HT₃-receptor antagonist, a single dose of 40 g/kg was given to 24 patients. All patients received cytostatic treatment expected to cause nausea and vomiting. During the first 24 h, 12 patients were completely protected from nausea and vomiting, 4 experienced nausea and 8 had moderate vomiting; mild headache occurred in 10 patients. No cardiovascular (including ECG) changes took place. Apart from headache, no neurological side effects occurred.Supported by a grant from the National Cancer Association of South Africa     

Managing COPD: no more nihilism!

This special issue of Patient Education and Counseling is long overdue. During most of the last two decades asthma, and notably asthma self-management has been in the spotlight, while COPD has had to endure a nihilistic approach. The first sign that interest was shifting to the treatment of COPD came from a few large randomized trials on the use of inhaled corticosteroids (ICS) in COPD. Although these studies demonstrated a moderate effect of ICS in COPD, it has become clear that true improvements in the management of this chronic disease will have to come from behavioral interventions. This special issue of Patient Education and Counseling is dedicated solely to the non-pharmaceutical management of COPD. It addresses many issues related to behavioral therapy, such as smoking cessation, exercise training, nutritional aspects, and self-management programs, including action plans to self-treat exacerbations. With the availability of all the treatment and management options, described in this special issue, a nihilistic attitude toward the patient with COPD is no longer justified.     

Combination of PCR targeting the VD2 of omp1 and reverse line blot analysis for typing of urogenital Chlamydia trachomatis serovars in cervical scrape specimens

In this study we developed and evaluated a new PCR-based typing assay, directed to the VD2 region of the omp1 gene, for the detection and typing of urogenital Chlamydia trachomatis infections. A nested VD2 PCR-reverse line blot (RLB) assay was developed for the typing of nine different urogenital serovars of C. trachomatis. The assay developed was tested with reference strains of C. trachomatis serovars and cervical scrapes of 86 Colombian women previously found to be positive for C. trachomatis by using plasmid PCR. Two sets of primers directed to the VD2 region of the omp1 gene of C. trachomatis were designed, and fragments of 220 and 166 bp were generated in the primary and nested PCRs, respectively. In addition, an RLB assay was developed to identify nine different urogenital serovars of C. trachomatis (Ba, D, E, F, G, H, I, J, and K) and group controls, including group B (Ba, D, and E), group C (I, J, K, and H), and an intermediate group (F and G). Using this assay, we were able to type 81 of the 86 samples (94.2%). Of these samples, 91.3% were single C. trachomatis infections, and 8.7% were multiple infections. The most common serovars identified were serovars D (22.2%), F (18.5%), G (13.6%), and E (12.3%). Of the women with multiple C. trachomatis infections, >50% contained both serovars D and E. The nested VD2 PCR-RLB developed is a simple, fast, and specific method for the identification of individual urogenital C. trachomatis serovars previously detected by using plasmid PCR. Moreover, it is an appropriate method for studying multiple C. trachomatis infections and for use in large epidemiological studies.