Reactive oxygen species and human spermatozoa: physiology and pathology

The role of reactive oxygen species (ROS) in the pathophysiology of human sperm function has been emphasized in recent years. ROS production in semen has been associated with loss of sperm motility, decreased capacity for sperm–oocyte fusion and loss of fertility. There is a current presumption that the most prolific source of ROS in sperm suspensions is an NADPH oxidase located in leukocytes or in spermatozoa which produces superoxide which is further converted to peroxide by the action of superoxide dismutase. Hydrogen peroxide has been recognized as the most toxic oxidizing species for human spermatozoa, which are very sensitive to lipid peroxidation owing to the high content of polyunsaturated fatty acids in their plasma membrane, though this is not the sole mechanism by which sperm function might be impaired by ROS. Although the excessive production of ROS is detrimental to human spermatozoa, there is a growing body of evidence which suggests that ROS are also involved in the physiological control of some sperm functions. This review focuses on the nature and source of the ROS generated by human spermataozoa as well as their operational mechanisms and their effects, which may be detrimental or beneficial.     

Just-in-Time Evidence-Based E-mail “Reminders” in Home Health Care: Impact on Patient Outcomes

OBJECTIVE: To assess the impact and cost-effectiveness of two information-based provider reminder interventions designed to improve self-care management and outcomes of heart failure (HF) patients. DATA SOURCES/STUDY SETTING: Interview and agency administrative data on 628 home care patients with a primary diagnosis of HF. STUDY DESIGN: Patients were treated by nurses randomly assigned to usual care or one of two intervention groups. The basic intervention was an e-mail to the patient's nurse highlighting six HF-specific clinical recommendations. The augmented intervention supplemented the initial nurse reminder with additional clinician and patient resources. DATA COLLECTION: Patient interviews were conducted 45 days post admission to measure self-management behaviors, HF-specific outcomes (Kansas City Cardiomyopathy Questionnaire-KCCQ), health-related quality of life (EuroQoL), and service use. PRINCIPAL FINDINGS: Both interventions improved the mean KCCQ summary score (15.3 and 12.9 percent, respectively) relative to usual care (p< or =.05). The basic intervention also yielded a higher EuroQoL score relative to usual care (p< or =.05). In addition, the interventions had a positive impact on medication knowledge, diet, and weight monitoring. The basic intervention was more cost-effective than the augmented intervention in improving clinical outcomes. CONCLUSIONS: This study demonstrates the positive impact of targeting evidence-based computer reminders to home health nurses to improve patient self-care behaviors, knowledge, and clinical outcomes. It also advances the field's limited understanding of the cost-effectiveness of selected strategies for translating research into practice.     

Synthesis and characterization of some poly[nitrilo-bis(phenylamino)phosphoranetriyl]s

Poly[nitrilo-bis(phenylamino)phosphoranetriyl]s ( 3a–d ) were synthesized and characterized in dilute solution and in the solid state. The synthesis was accomplished by thermal polymerization of of 2,2,4,4,6,6-hexachloro--triazatriphosphorane ( 1 ) at 240°C, followed by the reaction of the soluble product, poly(nitrilodichlorophosphoranetriyl) ( 2 ), with aniline or its derivatives. Elemental analyses show the presence of some residual chlorine, which, according to the IR spectra, does not seem to be ascribed to an incomplete substitution. All the polymers have intrinsic viscosities in tetrahydrofuran higher than 100ml g^?1, and high weight average molecular weights (M _w ≥ 7 · 10⁵). The molecular weight distribution is very broad (M _w/M _n ≥ 13,4) which could suggest either a branched structure or a complex mechanism of polymerization. From DSC measurements the glass transition temperatures are found to be between 70 and 98°C and the related values of specific heat increments, ΔC_,p, are between 0,13 J g^?1 K^?1 and 0,27 J g^?1 K^?1; the densities are in the order of 1,3 g ml^?1.     

Effect of defective connective tissue on the formation of aneurysmal-like structures in the rat testicular artery

Microscopic aneurysmal-like structures (ALS) develop spontaneously in the convoluted rat testicular artery and have been previously proposed as a model relevant to cerebral aneurysms. The effect of defects in connective tissue fibres on ALS formation was investigated by microscopy using two approaches: (i) the study of the effect of β-aminopropionitrile (BAPN), an inhibitor of the cross-linking of elastic and collagen fibres, on the incidence, size and morphology of ALS in spontaneously hypertensive rats (SHR) and their normotensive controls (WKY). The straight spermatic artery was studied for comparison. (ii) The determination of the incidence of spontaneous ALS in Brown Norway (BN) and Long Evans (LE) rats which are highly susceptible (BN) or resistant (LE) to the spontaneous rupture of the arterial internal elastic lamina. (i) BAPN increased the number and size of ALS in SHR and WKY rats and had no effect on the straight spermatic artery and (ii) ALS were more numerous and of greater size in BN than in LE rats. Taken together, these results show that defective connective tissue fibres may favour the formation and induce the enlargement of aneurysmal-like structures. By analogy, these data suggest that a lack of connective tissue fibre integrity may be of importance in cerebral aneurysm formation and development.     

A COMPARATIVE STUDY OF TENIDAP, A CYTOKINE-MODULATING ANTI-RHEUMATIC DRUG, AND DICLOFENAC IN RHEUMATOID ARTHRITIS: A 24-WEEK ANALYSIS OF A 1-YEAR CLINICAL TRIAL

Tenidap is a novel anti-rheumatic drug that combines cytokinemodulation with cyclo-oxygenase inhibition. This 24-week, multicentre,double-blind, randomized study compared the clinical efficacy,biochemical effects and safety of tenidap 120 mg/day (once daily)with diclofenac 150 mg/day (50 mg t.i.d.) in the treatment of384 patients with active rheumatoid arthritis. After 24 weeks,improvement with tenidap was significantly greater than withdiclofenac for all five primary efficacy parameters, two ofthe four secondary efficacy parameters and 11 of the 13 ArthritisImpact Measurement Scales assessments. The superior efficacyof tenidap was apparent after 4 weeks of treatment with furtherimprovements observed by 24 weeks. The probability of discontinuationdue to lack of efficacy was significantly greater in the diclofenacgroup. Tenidap but not diclofenac was associated with significant,rapid and sustained reductions in C-reactive protein and serumamyloid A levels and with a significant reduction in plasmainterleukin-6. The nature and frequency of side-effects weresimilar in the two groups as was the discontinuation rate fortreatment-related safety reasons. Tenidap was associated withan equal incidence of elevated transaminases, but a higher incidenceof mild (