[Markers of endothelial dysfunction in patients with arterial hypertension exposed to occupational irradiation of low intensity].

Aim To study the association between concentrations of endothelial dysfunction (ED) markers and arterial hypertension (AH) in people who were exposed to long-term action of "low-dose" ionizing radiation.Material and methods The study subjects were men of middle age (45-55 years) who were workers of the Siberian Integrated Chemical Plant with the length of service on the shop floor of at least 5 years. The subjects were divided into the main group (n=96) consisting of workers with grade 1-2 AH and the control group (n=48) consisting of arbitrarily healthy workers. Both groups contained workers who had been exposed to long-term occupational low-intensity irradiation (γ-radiation) and those not exposed to this irradiation. The study evaluated risk factors for cardiovascular diseases, presence of concomitant diseases, blood biochemistry (concentrations of glucose, high-sensitivity C-reactive protein (hsCRP), total cholesterol, low-density lipoproteins, high-density lipoproteins, triglycerides, creatinine, and ED markers, including endothelin, angiotensin II, von Willebrand factor, C-type natriuretic peptide, tissue plasminogen activator, tumor necrosis factor α (TNF-α), and homocysteine, major clinical data, total dose of external irradiation, and the content of 239Pu in the body.Results AH was associated primarily with excessive body weight and severity of atherogenic dyslipidemia and homocysteinemia. Higher plasma concentrations of TNF-α and a tendency to increasing hsCRP in the AH group, as distinct from the control group of arbitrarily healthy men, indicated a proinflammatory shift. The ED markers were related with clinical data of AH patients and associated with the lipid profile and increased blood concentrations of inflammatory mediators. The radiation exposure did not change the ED marker array in AH patients, which did not allow recommendation of the studied plasma indexes for detection of vascular endothelial injury in workers with AH of the Siberian Integrated Chemical Plant.Conclusion The study results evidenced the absence of adverse effects of long-term occupational exposure to low-intensity radiation on the vascular endothelium as evaluated by ED markers. In men aged 45-55 years, AH was associated primarily with excessive body weight, homocysteinemia, and atherogenic dyslipidemia.

Combination of a continuous-wave optical parametric oscillator and a femtosecond frequency comb for optical frequency metrology.

We combined a tunable continuous-wave optical parametric oscillator and a femtosecond Ti:sapphire laser frequency comb to provide a phase-coherent bridge between the visible and the mid-infrared spectral ranges. As a first demonstration of this new technique we performed a direct frequency comparison between an iodine-stabilized Nd:YAG laser at 1064 nm and an infrared methane optical frequency standard at 3.39 microm.

High-resolution Doppler-free molecular spectroscopy with a continuous-wave optical parametric oscillator.

We present a reliable, narrow-linewidth (100-kHz) continous-wave optical parametric oscillator (OPO) suitable for high-resolution spectroscopy applications. The singly resonant OPO with a resonated pump is based on periodically poled lithium niobate crystal and features a specially designed intracavity etalon, which permits precise tuning to any desired wavelength in a wide range. We demonstrate Doppler-free spectroscopy of a rovibrational transition of methane at 3.39 mum.