Sperm nitric oxide and motility: the effects of nitric oxide synthase stimulation and inhibition

Nitric oxide (NO) is synthesized from L-arginine by a family of enzymes known as the nitric oxide synthases (NOS). We have recently shown a NOS similar to constitutive brain NOS (bNOS) and endothelial NOS (ecNOS) to be present in spermatozoa. The aim of this study is to investigate NO production by human spermatozoa and the effects of stimulation and inhibition of NOS. This was carried out using the Iso-NO, an isolated NO meter and sensor, which provides rapid, accurate and direct measurements of NO. Semen samples with normozoospermic and asthenozoospermic profiles were prepared using a direct swim-up technique. Basal concentrations of NO and stimulated NO production were measured after exposure to the calcium ionophore (A23187; 0.01-10 microM) a potent activator of constitutive NOS. NO production in human spermatozoa was significantly increased by the addition of A23187 30 seconds after stimulation. Furthermore, this response was greatly diminished by pre-incubating the samples with competitive inhibitors of L-arginine, the substrate for NOS, before treatment with calcium ionophore. In the presence of N(G)-nitro-L-arginine methyl ester (L- NAME), N(G)-nitro-L-arginine (L-NA) or N(G)-methyl-L-arginine (L-NMMA; all at 10 microM), NO production was inhibited with a rank order of potency L-NAME > L-NMMA > L-NA which is in accordance with the inhibition of an endothelial type of constitutive NOS.      

Peripheral ameloblastoma: case report

Ameloblastoma is a benign tumour of the odontogenic tissues which may be aggressive in the involved area with a high rate of recurrence if not adequately removed, and represents 1% of all tumours of the mouth, generally appearing in the bones of the jaw. Although it is fairly rare, tumours with such histopathology have been described in the soft tissue and are named peripheral or extraosseus ameloblastoma. Potential cells of origin are ondontogenic residue of the dental lamina, pluripotent cells in the basal layer of the epithelial mucosa, and pluripotent cells of the minor salivary glands. Seven cases of extraosseus ameloblastoma in the extragengival area, unrelated to dental germs, have been described, six of which in the buccal mucosa and one in the mouth floor. We report a case of extraossous, extragengival ameloblastoma which originated in the subzygomatic area.     

Prospective comparative evaluation of quantitative-elastosonography (Q-elastography) and contrast-enhanced ultrasound for the evaluation of thyroid nodules: Preliminary experience

Purpose

To assess the effectiveness of semiquantitative elastosonography (Q-elastography) compared with contrast-enhanced ultrasound (CEUS) in differentiating the nature of thyroid nodules.

Methods and materials

Forty-eight consecutive patients (35 males, 13 females, range: 34–69 years, mean: 49.4 years), candidate to surgery, previously detected at color-Doppler ultrasound (CDUS), were prospectively examined with elastosonography with dedicated semiquantitative software (Q-Elastography, Toshiba XG) and CEUS (Technos Mylab 70 Gold X, and Toshiba XG) before surgery. CEUS and elastosonography were evaluated by two investigators in consensus. Comparison between the CEUS pattern and elastonographic strain ratio observed and expected frequencies for the diagnoses was evaluated with χ² test or with Fisher exact test.

Results

Fifty-three nodules (19 papillary carcinoma, 32 hyperplasia, and 2 follicular adenoma) in 48 patients were available for analysis. Regarding echogenicity score, sensitivity, specificity, PPV and NPV of conventional US were 81%, 50%, 56%, 77%; according to Q-elastography, sensitivity, specificity, PPV and NPV were 95%, 88%, 97% and 91% respectively; whereas concerning CEUS, sensitivity specificity PPV and NPV were 79%, 91%, 83% and 89% respectively. Both CEUS and Q-elastography were more specific than US (p < 0.01), with not statistical significant difference with regard to sensitivity.

Conclusions

The results of the present study suggest that Q-elastography is a valuable tool in the characterization of thyroid nodules and it seems to be more sensitive than CEUS.     

Yoga lifestyle intervention reduces blood pressure in HIV‐infected adults with cardiovascular disease risk factors*

Objective

People living with HIV infection are at increased risk for developing cardiovascular disease (CVD). Safe and effective interventions for lowering CVD risk in HIV infection are high priorities. We conducted a prospective, randomized, controlled study to evaluate whether a yoga lifestyle intervention improves CVD risk factors, virological or immunological status, or quality of life (QOL) in HIV‐infected adults relative to standard of care treatment in a matched control group.

Methods

Sixty HIV‐infected adults with mild–moderate CVD risk were assigned to 20 weeks of supervised yoga practice or standard of care treatment. Baseline and week 20 measures were: 2‐h oral glucose tolerance test with insulin monitoring, body composition, fasting serum lipid/lipoprotein profile, resting blood pressures, CD4 T‐cell count and plasma HIV RNA, and the Medical Outcomes Study Short Form (SF)‐36 health‐related QOL inventory.

Results

Resting systolic and diastolic blood pressures improved more (P=0.04) in the yoga group (−5 ± 2 and −3 ± 1 mmHg, respectively) than in the standard of care group (+1 ± 2 and+2 ± 2 mmHg, respectively). However, there was no greater reduction in body weight, fat mass or proatherogenic lipids, or improvements in glucose tolerance or overall QOL after yoga. Immune and virological status was not adversely affected.

Conclusion

Among traditional lifestyle modifications, yoga is a low‐cost, simple to administer, nonpharmacological, popular behavioural intervention that can lower blood pressure in pre‐hypertensive HIV‐infected adults with mild–moderate CVD risk factors.

     

Compressive properties of commercially available polyurethane foams as mechanical models for osteoporotic human cancellous bone

Background  

Polyurethane (PU) foam is widely used as a model for cancellous bone. The higher density foams are used as standard biomechanical test materials, but none of the low density PU foams are universally accepted as models for osteoporotic (OP) bone. The aim of this study was to determine whether low density PU foam might be suitable for mimicking human OP cancellous bone.     

Primary care anticoagulant clinic management using computerized decision support and near patient International Normalized Ratio (INR) testing: routine data from a practice nurse-led clinic

BACKGROUND: Increasing indications for warfarin therapy has led to increased pressure on primary care to undertake therapeutic monitoring. OBJECTIVE: This study evaluates a primary care model of oral anticoagulation monitoring which utilises computerized decision support (CDSS) and near patient testing (NPT) within a practice nurse-led clinic. Whilst this has been shown to be a successful model under trial conditions, this paper reports the first data from a long-standing clinic, outside a formal study. METHOD: A prospective evaluation of therapeutic and clinical control of all patients taking warfarin within one inner city general practice. Data were collected via CDSS. RESULTS: 29 patients were seen in 208 appointments. The mean percentage of patients within therapeutic range was 72%. The costs to the practice were pound sterling 1751. The costs the practice would have incurred had these patients been seen at the hospital with the same frequency would have been pound sterling 2290. CONCLUSIONS: The use of CDSS and NPT for nurse-delivered oral anticoagulation monitoring could enable the safe transfer of the majority of patients from secondary to primary care. Funding mechanisms to support the transfer of costs will be essential for most practices, as will be the maintenance of adequate staff training and quality assurance.