Tumor vascular signals in renal masses: detection with Doppler US

The vascularity of 49 renal masses (26 malignant and 23 benign lesions) was investigated with duplex Doppler ultrasound. Doppler signals obtained at the margins of renal masses were defined as "tumor signals" when the Doppler-shifted frequency of the lesion exceeded the frequency shift in the ipsilateral main renal artery. These exceeded 2.5 kHz with a 3-MHz insonating frequency. Among the 26 renal masses that subsequently proved to be malignant, tumor signals were obtained in 15 of 18 (83%) untreated renal cell carcinomas, in three of four Wilms tumors, and in two patients with metastases to the kidney, but not in the one patient with lymphoma. None of the 23 benign renal masses demonstrated tumor signals. Tumor vascularity in malignant lesions gives rise to abnormal, high-velocity, Doppler-shifted signals that can help in the differential diagnosis of renal masses.     

Detection of reactive oxygen species (ROS) and apoptosis in human fragmented embryos

In human in-vitro fertilization (IVF)-embryo transfer, the in-vitro culture environment differs from in-vivo conditions in that the oxygen concentration is higher, and in such conditions the mouse embryos show a higher concentration of reactive oxygen species (ROS) in simple culture media. ROS are believed to cause damage to cell membranes and DNA fragmentation in somatic cells. This study was conducted to ascertain the level of H2O2 concentration within embryos and the morphological features of cell damage induced by H2O2. A total of 62 human oocytes and embryos (31 fragmented, 15 non-fragmented embryos, 16 unfertilized oocytes) was obtained from the IVF-embryo transfer programme. The relative intensity of H2O2 concentrations within embryos was measured using 2',7'-dichlorodihydrofluorescein diacetate by Quanti cell 500 fluorescence imaging and DNA fragmentation was observed with transmission electron microscopy and an in-situ apoptosis detection kit. The H2O2 concentrations were significantly higher in fragmented embryos (72.21 +/- 9.62, mean +/- SEM) compared to non-fragmented embryos (31.30 +/- 3.50, P < 0.05) and unfertilized oocytes (30.75 +/- 2.67, P < 0.05). Apoptosis was observed only in fragmented embryos, and was absent in non-fragmented embryos. Electron microscopic findings confirmed apoptotic bodies and cytoplasmic condensation in the fragmented blastomeres. We conclude that there is a direct relationship between increased H2O2 concentration and apoptosis, and that further studies should be undertaken to confirm these findings.      

Biological actions of nerve growth factor in the peripheral nervous system

Since the discovery of nerve growth factor (NGF), its role in the physiology/pathophysiology of nerve function has been under intense investigation. More recently, the potential of recombinant human NGF (rhNGF) as a putative treatment for peripheral neuropathies, in particular diabetic polyneuropathy and HIV-associated sensory neuropathy, is being explored. In animal models of diabetes, depletion of endogenous NGF levels has been demonstrated in foot skin and skeletal muscle; these levels reduce further with increasing disease duration. Preclinical studies in animal models of diabetes have shown that administration of NGF can reverse or alleviate impairment in nerve function.     

Symptoms as the main problem in primary care: A cross-sectional study of frequency and characteristics

Objective. The aim was to study symptoms managed as the main problem by the general practitioner (GP) and to describe the frequencies and characteristics of presented symptoms when no specific diagnosis could be made. Design. Cross- sectional study. Setting. General practices in the Central Denmark Region. Subjects. In total, 397 GPs included patients with face-to-face contacts during one randomly assigned day in 2008–2009; 7008 patients were included and 5232 presented with a health problem. Main outcome measures. GPs answered a questionnaire after each patient contact. Symptoms and specific diagnoses were subsequently classified using the International Classification of Primary Care (ICPC). Symptom frequency, comorbidity, consultation length, and GP-assessed final outcome and burden of consultations were analysed. Results. The GPs could not establish a specific diagnosis in 36% of patients with health problems. GPs expected that presented symptoms would not result in a future specific diagnosis for half of these patients. Musculoskeletal (lower limb and back) and respiratory (cough) symptoms were most frequent. More GPs had demanding consultations when no specific diagnosis could be made. Higher burden was associated with age, comorbidity, and GP expectancy of persistent symptoms when no diagnosis could be made. Conclusion. Interpretation and management of symptoms is a key task in primary care. As symptoms are highly frequent in general practice, symptoms without a specific diagnosis constitute a challenge to GPs. Nevertheless, symptoms have been given little priority in research. More attention should be directed to evidence-based management of symptoms as a generic phenomenon to ensure improved outcomes in the future.