Comparison of nasal prong pressure and thermistor measurements for detecting respiratory events during sleep

INTRODUCTION AND OBJECTIVES: Thermistor (TH) measurements have been traditionally used to determine airflow during polysomnographic studies (PSG). However, low accuracy in detecting hypopneas is a major drawback. Nasal prong pressure (NPP) measurements are becoming increasingly popular for quantifying respiratory events during sleep. We prospectively compared NPP and TH measurements with respect to their ability to detect respiratory events during routine PSG. METHODS: Forty consecutive patients (26 male, 14 female) with clinically suspected sleep-disordered breathing (SDB) underwent routine diagnostic PSG. Airflow was measured using NPP and TH devices simultaneously. PSG was scored manually according to R and K criteria. Respiratory events were scored in two passes. During the first pass, the TH signal was disabled and the NPP signal was scored. During the second pass, the NPP signal was disabled and the TH signal was scored. Scorers for one method were blinded from the results of the other method. To assess respiratory events, we used the respiratory arousal index (RAI), which was defined as the number of apneas and/or hypopneas followed by an arousal per hour of sleep, as detected by TH (RAI-TH) or NPP (RAI- NPP). Agreement analysis of the results obtained using the two different techniques was performed using the methodology of Bland-Altman. RESULTS: Twenty-six patients had obstructive sleep apnea, 10 had respiratory effort-related arousals and 4 had habitual snoring. The failure time of the flow signal on the raw data was not different between the two methods (NPP: 6 +/- 13 min, TH: 4 +/- 7 min). The Bland-Altman analysis of RAIs demonstrated that more events were nearly always detected using NPP compared to TH devices (44.4 +/- 37 vs. 35.4 +/- 31, p < 0.001). No difference in the index of central apneas between the two methods could be detected. Sleep position had no effect on either measurement method. CONCLUSIONS: NPP measurements are superior to TH measurements for detecting obstructive respiratory events during sleep. Measurement of NPP is a simple, practical, sensitive and reliable method for detecting the whole spectrum of SDB. We recommend incorporating nasal prongs in routine polysomnographic monitoring.     

A multicenter trial of the use of the proteolytic enzyme inhibitor aprotinin in colorectal surgery

Animal studies have demonstrated the value of the proteolytic enzyme inhibitor, aprotinin, in reducing collagen breakdown and improving the healing of experimental colonic anastomoses. A double-blind, multicenter, prospective trial has evaluated the use of aprotinin in the prevention of anastomic leakage in patients. Two hundred sixteen patients undergoing colonic resection and anastomosis were studied. Patients were randomized to receive either aprotinin or placebo intravenously, peroperatively, and for the first three postoperative days. Anastomotic integrity was assessed clinically and by Hypaque^® enema on the tenth postoperative day. Although the use of aprotinin was not associated with a significant overall decrease in anastomotic leakage rates, in 95 patients undergoing anterior resection, leakage rates in those receiving aprotinin (clinical 10.8 percent; radiologic 32.4 percent) were lower than in those receiving placebo (17.2 percent and 43.1 percent, respectively). An apparent adverse association was noted, however, in patients undergoing left hemicolectomy or sigmoid colectomy who received aprotinin.     

Increased plasma adhesion molecule levels in patients with heart failure who have ischemic heart disease and dilated cardiomyopathy

BACKGROUND: Inflammatory mechanisms, including leukocyte activation, appear to play a pathogenetic role in the development of heart failure. Vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) are important mediators of leukocyte adhesion to vascular endothelium. The plasma levels of the soluble form of these molecules may be elevated in chronic inflammation. METHODS AND RESULTS: We measured plasma VCAM-1 and ICAM-1 levels (in nanograms per milliliter) with the commercially available enzyme-linked immunosorbent assay method in 12 patients (9 male, 3 female, aged 64 +/- 8 years) with dilated cardiomyopathy and heart failure, in 23 patients (23 male, aged 65 +/- 9 years) with ischemic cardiomyopathy and heart failure, and in 11 healthy control subjects (8 male, 3 female, aged 49 +/- 14 years). Plasma ICAM-1 levels were higher both in patients with dilated cardiomyopathy (363 +/- 77 ng/mL, P <.05) (mean +/- SEM) and in those with ischemic heart disease (320 +/- 32 ng/mL, P <.05) than in control subjects (225 +/- 29 ng/mL). VCAM-1 levels were also higher in both groups with heart failure (664 +/- 73 ng/mL) than in control subjects (551 +/- 60 ng/mL). VCAM-1 levels were higher in patients with class IV compared with those with class II and III heart failure. CONCLUSIONS: Plasma adhesion molecule levels are increased in patients with heart failure and are unrelated to the presence or absence of angiographically demonstrable atherosclerotic coronary artery disease. The plasma level of VCAM-1 correlates with the severity of heart failure.     

Luteal cell 3-hydroxy-3-methylglutaryl coenzyme-A reductase activity and cholesterol metabolism throughout pregnancy in the rat

The objective of this study was to investigate changes in luteal cell cholesterol biosynthetic capacity, cholesterol accumulation, lipoprotein receptor activity, and in vivo steroidogenesis during pregnancy. Cholesterol biosynthetic capacity was assessed by measuring both the activity and the content of the rate-limiting enzyme 3-hydroxy-3-methylglutaryl coenzyme-A (HMG-CoA) reductase and by monitoring [14C]acetate incorporation into luteal sterols. The results showed that HMG-CoA reductase activity increased steadily during the first few days of pregnancy and reached a peak value on day 10. Subsequently, enzyme activity dropped precipitously and remained low until parturition. A parallel decline in the rate of conversion of 14C-labeled sterols was observed. Such changes in HMG-CoA reductase activity were not related to the phosphorylation/dephosphorylation state of the enzyme, but were due to a reduction in the amount of enzyme protein, as determined by the immunoblotting technique. Despite the highly active HMG-CoA reductase in the first half of pregnancy, very little cholesterol ester was stored, and serum progesterone concentrations were only about 50-75 ng/ml. However, from midpregnancy, the corpus luteum became capable of storing more cholesterol ester and producing more progesterone at a time when its ability to synthesize cholesterol declined. At this stage, luteal cells appear to shut off de novo synthesis and use principally exogenous cholesterol. To find out whether this is due to an increase in the number of high density lipoprotein (HDL) receptors, HDL-binding activity was determined in luteal cells throughout pregnancy. Whereas the Kd and the number of binding sites per mg protein were similar between days 6-18, the total content of HDL receptor increased markedly with the size of the corpus luteum. In summary, the present investigation indicates that pregnancy profoundly influences the ability of the corpus luteum to acquire, synthesize, and process the cholesterol substrate needed for steroidogenesis.     

Histological progression during short-term follow-up of patients with chronic hepatitis C virus infection

Assessment of prognosis from hepatitis requires liver histology. When the fibrosis stage is known, and if the fibrosis progression rate can be established, time to development of cirrhosis can be calculated. The fibrosis progression rate can be calculated from a single biopsy when duration of infection prior to biopsy is known. Sequential biopsies can also be examined. In this work, we studied histological activity and fibrosis stage in liver biopsies of 157 hepatitis C virus (HCV)-infected patients, including 92 for whom the approximate duration of infection was known. The mean fibrosis progression rate was 0.09 units per year, and was not influenced by mode of infection or viral genotype. Forty-six patients who had very mild histological changes in the initial biopsy underwent repeat biopsy 2 years later (with no intervening anti-viral treatment). Comparison of paired biopsies confirmed a tendency to histological progression and increasing hepatic fibrosis (mean, 0.15 fibrosis units per year). A normal baseline alanine aminotransferase (ALT) value was associated with slow fibrosis progression before baseline biopsy and between biopsies. These data do not differ from published cross-sectional and longitudinal studies, and suggest that histological progression will be observed during follow-up of most patients, including those with mild histological changes at time of initial assessment.     

Medicinal chemistry of oxazines as promising agents in drug discovery

Oxazines have brought much synthetic interest due to their extensive biological activities. These are the important category of heterocycles, which may be formally derived from benzene and its reduction products by convenient substitution of carbon (and hydrogen) atoms by nitrogen and oxygen. In the last few decades, oxazine derivatives have documented as worthy synthetic intermediates and also blessed with notable sedative, analgesic, anticonvulsant, antipyretic, antimicrobial, antitubercular, antimalarial, antioxidant, and anticancer activities. Nowadays, it is important to develop new classes of compounds with more effective mechanisms due to drug resistance activity in which the ability of drug to effectively treat disease can be reduced. The aim of the article is to collect and make a more generalized review on the synthesis of oxazine derivatives and their pharmaceutical and biological activities. We hope this review will provide ample references for the researchers concerned with azines in generally and oxazines in particular.     

VE1 immunohistochemistry is an adjunct tool for detection of BRAF V600E mutation: Validation in thyroid cancer patients

Papillary thyroid carcinoma (PTC) is the most common endocrine malignancy among other endocrine tumors, and BRAF ^V600E is a frequent genetic mutation occurring in the disease. Although different molecular techniques, most importantly sequencing has been widely recognized as a gold standard but molecular diagnosis remains an expensive, laborious, and time‐intensive process. Recently, immunohistochemistry (IHC) with anti‐BRAF V600E (VE1) antibody has increased practical utility and implemented clinically for the detection of BRAF ^V600E mutation. Therefore, the study aimed to evaluate diagnostic accuracy of VE1 IHC for detecting the BRAF ^V600E mutation frequency and clinical implementation in diagnostic laboratories. In this study, 72 formalin fixed paraffin‐embedded tissues (FFPE) were used to determine the BRAF ^V600E mutation status using IHC and Sanger sequencing. The mutation was found in 29% and 28% cases using IHC and Sanger sequencing, respectively. Furthermore, the results showed 100% sensitivity, 98.07% specificity, 95.2% positive predictive value, and 100% negative predictive value. Notably, significant associations were found between BRAF ^V600E status and tumor stage, tumor focality, and extrathyroidal extensions, respectively. VE1 IHC was found to be a highly sensitive, specific, and diagnostically accurate method in this cohort. Therefore, BRAF ^V600E detection through IHC has been considered as the best tailored technique for routine pathology laboratories.     

Efficacy of multi-wave locked system laser therapy on nerve regeneration after crushing in Wister rats

[Purpose] To investigate the efficacy of the multi-wave locked system laser therapy on the regeneration of peripheral nerve injuries by evaluating the functional, electrophysiological, and morphological changes of the crushed sciatic nerve in Wistar rats. [Materials and Methods] Sixty male Wistar rats (200–250 g) were randomly assigned to control negative, control positive, or laser groups and subjected to no laser therapy or crushing, to crushing without laser therapy, or crushing followed by multi-wave locked system laser therapy five times/week for four weeks (power=1 W, energy density=10 J/cm², total energy=100 J), respectively. Functional, electrophysiological, and morphometric analyses were performed before and 7, 15, 21, and 28 days after crushing. The sciatic functional index, compound motor action potential amplitude, motor nerve conduction velocity, and nerve and myelin sheath diameters were measured. [Results] The sciatic functional index value decreased significantly, while the compound motor action potential amplitude, motor nerve conduction velocity, nerve diameter, and myelin sheath diameter increased significantly in the laser group post-treatment compared to the values in the control groups. [Conclusion] Multi-wave locked system laser therapy was effective in accelerating the regeneration of crushed sciatic nerves in Wistar rats.