Use of the Implantable Loop Recorder in Evaluation of Patients with Unexplained Syncope

Syncope is a complex symptom with multiple potential etiologies that can be difficult to establish. The major obstacles to diagnosis are the periodic and unpredictable nature of events and the high spontaneous remission rate. Short-term ECG monitoring often is unproductive when initial noninvasive testing is negative due to the low probability of recurrence during the brief monitoring period. Implantable loop recorders extend the ability to monitor cardiac patients, enhancing the diagnostic yield to as high as 85% in difficult to diagnose syncope. Several recent studies suggest that prolonged monitoring with an implantable loop recorder has a role in patients with syncope and conduction disturbances, negative tilt testing, and unexplained seizures, and may be superior to conventional testing with tilt and electrophysiologic studies. (J Cardiovasc Electrophysiol, Vol. 14, pp. S70-S73, September 2003, Suppl.)     

HIV-1 gp120 AND IMMUNE NETWORK

It has been demonstrated that the immunodominant V3 loop of HIV-1 gp120 and its flanking regions bear sequence and structural homology to the framework and complementarity-determining regions of human immunoglobulins. It has been proposed that the Ig-like domain of gp120 might encode idiotypes and in this way permit HIV-1 entry into the immune regulatory network. This notion is strongly supported by results demonstrating that the anti-V3 loop and anti-Ig antibodies of healthy individuals share complementary structure and that V3 reactive antibodies are present in HIV-negative sera. This might be the mechanism by which HIV induces immunological abnormalities, and it should be taken into consideration in AIDS vaccine development.     

Closed loop obstruction: Pictorial essay

Closed loop obstruction occurs when a segment of bowel is incarcerated at two contiguous points. The diagnosis is based on multiple transitional zones. The incarcerated loops appear in U or C form or present a radial layout around the location of the obstruction. It's very important to specify the type of obstruction because, in patients with simple bowel obstruction, a conservative approach is often advised. On the other hand, a closed loop obstruction immediately requires a surgical approach because of its high morbidity and the risk of death in case of a late diagnosis.     

Molecular fixative enables expression microarray analysis of microdissected clinical cervical specimens

Formalin-fixed tissue has been a mainstay of clinical pathology laboratories, but formalin alters many biomolecules, including nucleic acids and proteins. Meanwhile, frozen tissues contain better-preserved biomolecules, but tissue morphology is affected, limiting their diagnostic utility. Molecular fixatives promise to bridge this gap by simultaneously preserving morphology and biomolecules, enabling clinical diagnosis and molecular analyses on the same specimen. While previous reports have broadly evaluated the use of molecular fixative in various human tissues, we present here the first detailed assessment of the applicability of molecular fixative to both routine histopathological diagnosis and molecular analysis of cervical tissues. Ten specimens excised via the loop electrosurgical excision procedure, which removes conical tissue samples from the cervix, were cut into alternating pieces preserved in either formalin or molecular fixative. Cervical specimens preserved in molecular fixative were easily interpretable, despite featuring more eosinophilic cytoplasm and more recognizable chromatin texture than formalin-fixed specimens. Immunohistochemical staining patterns of p16 and Ki-67 were similar between fixatives, although Ki-67 staining was stronger in the molecular fixative specimens. The RNA of molecular fixative specimens from seven cases representing various dysplasia grades was assessed for utility in expression microarray analysis. Cluster analysis and scatter plots of duplicate samples suggest that data of sufficient quality can be obtained from as little as 50 ng of RNA from molecular fixative samples. Taken together, our results show that molecular fixative may be a more versatile substitute for formalin, simultaneously preserving tissue morphology for clinical diagnosis and biomolecules for immunohistochemistry and gene expression analysis.     

DETERMINATION OF VIRAL TROPISM BY GENOTYPING AND PHENOTYPING ASSAYS IN BRAZILIAN HIV-1-INFECTED PATIENTS

The clinical application of CCR5 antagonists involves first determining the coreceptor usage by the infecting viral strain. Bioinformatics programs that predict coreceptor usage could provide an alternative method to screen candidates for treatment with CCR5 antagonists, particularly in countries with limited financial resources. Thus, the present study aims to identify the best approach using bioinformatics tools for determining HIV-1 coreceptor usage in clinical practice. Proviral DNA sequences and Trofile results from 99 HIV-1-infected subjects under clinical monitoring were analyzed in this study. Based on the Trofile results, the viral variants present were 81.1% R5, 21.4% R5X4 and 1.8% X4. Determination of tropism using a Geno2pheno_[coreceptor] analysis with a false positive rate of 10% gave the most suitable performance in this sampling: the R5 and X4 strains were found at frequencies of 78.5% and 28.4%, respectively, and there was 78.6% concordance between the phenotypic and genotypic results. Further studies are needed to clarify how genetic diversity amongst virus strains affects bioinformatics-driven approaches for determining tropism. Although this strategy could be useful for screening patients in developing countries, some limitations remain that restrict the wider application of coreceptor usage tests in clinical practice.     

The Clearance of High-Risk Human Papillomavirus is Sooner After Thin Loop Electrosurgical Excision Procedure (t-LEEP)

Abstract

Purpose/aim of the study: To investigate high-risk human papillomavirus (HPV) infection clearance following thin loop electrosurgical excision procedure (t-LEEP) among patients with cervical benign lesion. Materials and Methods: This retrospective study analyzed clinical data from patients with cervical benign lesion and HPV infection, who had undergone t-LEEP (T-Group), compared with patients with HPV infection undergone no treatment (NT-Group). Both groups attended regular follow-up between January 2008 and January 2012. Kaplan–Meier analysis was used to compare the HPV clearance time. Results: The average clearance time was 7.7?months (M) (95% confidence interval [CI]: 6.5–8.9 M) in T-Group, and 10.4?M (95%CI: 9.4–11.3 M) in NT-Group, with significant difference between groups (p?=?0.003). Among patients with low viral load, the HPV clearance times were 7.6?M (95%CI: 6.3–9.0 M) in T-Group and 9.7?M (95%CI: 8.6–10.8 M) in NT-Group (p?=?0.042). Among patients with high viral load, the HPV clearance times were 8.0?M (95%CI: 5.3–10.6 M) in T-Group and 11.4?M (95%CI: 9.7–13.1 M) in NT-Group (p?=?0.041). The average time of HPV clearance in T-Group was shorter than NT-Group in all age groups, with significant differences in ≤29Y-group (p?=?0.008) and 30–39Y-group (p?=?0.005). The accumulated clearance rate of HPV infection at sixth month and 12th month were 24.5% and 67.9% in T-Group, 7.8% and 43.1% in NT-Group, with significant differences (p?=?0.001 at 6th month, p?=?0.032 at 12th month). Conclusions: T-LEEP accelerates the clearance of high-risk HPV infection and make the HPV infection rates dropped rapidly in the first year.