Pulmonary hypertension in patients with obstructive sleep apnea syndrome

BACKGROUND: Obstructive sleep apnea syndrome (OSAS) is associated with an increased cardiovascular morbidity, including pulmonary hypertension. Little is known about factors influencing the degree of pulmonary hypertension and left ventricular dysfunction in patients with OSAS, especially in the absence of concomitant lung disease. METHODS: Right heart catheterization, arterial blood gas analysis, and pulmonary function tests were performed in 92 consecutive patients (81 men and 11 women; mean +/- SD age, 53.1 +/- 11.0 years) with polysomnographically verified OSAS, in whom clinically significant lung disease was excluded. RESULTS: Eighteen patients (20%) had mild pulmonary hypertension; 8 (44%) of them also had increased pulmonary capillary wedge pressures (Ppew). Left ventricular dysfunction was associated with arterial hypertension. Only Ppcw (r = 0.51; P < .001) and the percentage of time during sleep spent with an oxygen saturation below 90% (as an indicator of the severity of OSAS) (r = 0.34; P = .003) were significantly and independently associated with pulmonary artery pressure. CONCLUSIONS: Obstructive sleep apnea syndrome can cause mild pulmonary hypertension, even in the absence of pulmonary disease. In these patients, pulmonary hypertension is of the postcapillary type, or-in patients with normal left ventricular function-strongly related to the severity of OSAS. Our findings indicate that OSAS may constitute an important, and independent, risk factor for pulmonary hypertension.     

Philanthropic goals

Cor triatriatum is a rare cardiac anomaly which can be congenital or acquired in origin. Congenital cor triatriatum is due to an alteration of the common pulmonary vein resorption and therefore the left atrium is divided into two chambers, a proximal one, in communication with the pulmonary veins, and a distal one, in communication with the mitral valve orifice. The diagnosis is usually made at birth, but in rare cases, when the communication between the two chambers is wide and the patient is asymptomatic, the lesions may be diagnosed incidentally during a routine echocardiographic examination. We report a 32-year-old man, admitted to our hospital with a diagnosis of aortic insufficiency, in whom echocardiography revealed the presence of cor triatriatum. The patient underwent aortic valve replacement and resection of the atrial membrane. Histology of the aortic valve revealed myxoid degeneration of the spongiosa.     

Allylmercapturic acid as urinary biomarker of human exposure to allyl chloride

OBJECTIVE: To evaluate the use of urinary mercapturic acids as a biomarker of human exposure to allyl chloride (3-chloropropene) (AC). During three regular shut down periods in a production factory for AC, both types of variables were measured in 136 workers involved in maintenance operations. METHODS: Potential airborne exposure to AC was measured by personal air monitoring in the breathing zone. In total 205 workshifts were evaluated. During 99 workshifts no respiratory protection equipment was used. Mercapturic acid metabolites were measured in urinary extracts by gas chromatography-mass spectrometry (GC-MS). RESULTS: During 86 work shifts when no respiratory protection was used the air concentrations of AC were below the Dutch eight hour time weighted average (8 h-TWA) occupational exposure limit (OEL) of AC (3 mg/m3), whereas in 13 workshifts the potential exposure, as measured by personal air monitoring, exceeded the OEL (3.3 to 17 mg/m3). With the aid of GC-MS, 3-hydroxypropylmercapturic acid (HPMA) was identified as a minor and allylmercapturic acid (ALMA) as a major metabolite of AC in urine samples from the maintenance workers exposed to AC. The concentrations of ALMA excreted were in a range from < 25 micrograms/l (detection limit) to 3550 micrograms/l. The increases in urinary ALMA concentrations during the workshifts correlated well with the 8h-TWA air concentrations of AC (r = 0.816, P = 0.0001, n = 39). Based on this correlation, for AC a biological exposure index (BEI) of 352 micrograms ALMA/g creatinine during an eight hour workshift is proposed. In some urine samples unexpectedly high concentrations of ALMA were found. Some of these could definitely be attributed to dermal exposure to AC. In other cases garlic consumption was identified as a confounding factor. CONCLUSION: The mercapturic acid ALMA was identified in urine of workers occupationally exposed to airborne AC and the increase in ALMA concentrations in urine during a workshift correlated well with the 8 h-TWA exposure to AC. Garlic consumption, but not smoking, is a potential confounding factor for this biomarker of human exposure to AC.     

Chromosomal anomalies in stage D1 prostate adenocarcinoma primary tumors and lymph node metastases detected by fluorescence in situ hybridization

We previously reported a HPLC assay method using fluorimetric detection for the simultaneous determination of urinary N2-(3-aminopropyl)biopterin (oncopterin, a natural pteridine newly found in urine from cancer patients), biopterin and neopterin. We now have observed that an unknown substance, which may be derived from methotrexate, in urine from a patient with stomach cancer interfered with the assay of oncopterin and demonstrated that oncopterin could be completely separated from the unidentified substance by HPLC using a Nucleosil 100-5SA strong cation-exchange column. Furthermore, oncopterin was not detectable by this HPLC-fluorimetric method in urine samples from patients with stomach cancer who were not treated with methotrexate. The content of urinary oncopterin from cancer patients is supposed to be very low, with less than 1 mumol/mol creatinine. The present results indicate that the peak found with elution from the C18 column was a methotrexate-derived compound and co-eluted with the analyte oncopterin.     

'True' fasting serum insulin level, insulin resistance syndrome and coronary artery disease

BACKGROUND: Increased fasting serum insulin level not associated with hypoglycemia is considered to be a practical indicator of the insulin resistance syndrome, a frequent risk factor for atherosclerosis in industrialized countries. However, in most studies, insulin was measured by using antibodies which cross-react with proinsulin and 31/32, 32/33 split products of insulin. We re-examined the correlations between the insulin resistance syndrome and 'true' fasting serum insulin level. METHODS: We studied 242 post-menopausal women (age 63 +/- 8 years), a population in whom insulin resistance syndrome is particularly frequent. Serum insulin was measured by a recent specific microparticle immunoassay. RESULTS: There was a significant correlation between elevated 'true' fasting serum insulin level and various constituents of the insulin resistance syndrome, such as obesity, dyslipidemia (hypertriglyceridemia, increased apolipoprotein B and decreased high-density lipoprotein cholesterol and apolipoprotein A1 concentrations), increased serum glucose, uric acid levels, and plasminogen activator inhibitor type I concentration, as well as increased frequency of diabetes. There was also a correlation between insulin level and various manifestations of coronary artery disease: patients in the highest quartile of 'true' insulin level had significantly more entirely occluded coronary arteries than in the lowest one. Similarly, in the highest insulin quartile more patients had occluded arteries with lumen diameter stenoses greater than 50% (P < 0.05) and more of them had history of previous myocardial infarction approaching the level of significance (P = 0.0587) than in the lowest one. Most of these correlations were also noted in nondiabetic people. CONCLUSIONS: An increase of 'true' fasting serum insulin level is a useful practical index to identify patients with the insulin resistance syndrome exposed to increased risk of coronary artery disease.     

过期药呋塞米在醋酸溶液中对冷轧钢的缓蚀作用

通过电导率测量、pH测量、同步热分析(STA)、Tafel极化曲线法和电化学交流阻抗谱法研究了不同浓度和温度下过期药呋塞米在1 mol/L的醋酸溶液中对冷轧钢缓蚀作用。实验结果表明:过期药呋塞米在1 mol/L的醋酸溶液中对冷轧钢有较好的缓蚀效果,且缓蚀率随着缓蚀剂浓度和温度的增加而增大。该缓蚀剂在醋酸中对钢是一种抑制阴极和阳极的混合型缓蚀剂。缓蚀剂在冷轧钢表面的吸附符合Langmuir吸附等温式,其吸附是自发、物理吸附过程。同步热分析还说明了该缓蚀剂易稳定吸附在冷轧钢表面。