Biophysical substantiation of photoplethysmography in reflected light

Conclusions The coefficient of effectiveness of collecting the useful signal A and, consequently, the change in the value of RF reflected from tissues of the BO substantially depend on the arrangement of the reflecting surface of these tissues relative to the PT used. An important factor in collecting the useful signal is the design of the PT itself, i.e., the dimensions of its components and their arrangement relative to one another. However, since the same PT, as a rule, is used in experimental investigations, the value of the RF reflected from the investigated tissues will depend practically only on the change in the position of the reflecting surface relative to the working surface of the PT, which the cardiovascular system introduces into the PPM (with consideration of the assumptions made). Depending on whether this system is normal or various pathologies are present in it, the value of the reflected RF will change.As for the optimal selection of the real design of a PT, the results obtained in calculations by formula (16) make it possible to find the value of the coefficient of effectiveness of collecting useful information practically for all types of radiators and photodetectors, including fiber light pipes, being used in instruments (of the photoplethysmograph type).Institute of Radio Engineering and Electronics, Academy of Sciences of the USSR, Moscow. Central Scientific-Research Institute of Stomatology, USSR Ministry of Health, Moscow. Translated from Meditsinskaya Tekhnika, No. 2, pp. 4–7, March–April, 1990.     

Prevalence of osteoporosis and incidence of hip fracture in women - secular trends over 30 years

Background  

The number of hip fractures during recent decades has been reported to be increasing, partly because of an increasing proportion of elderly women in the society. However, whether changes in hip fracture annual incidence in women are attributable to secular changes in the prevalence of osteoporosis is unclear.     

Anthropometric and Dietary Evaluations in a Sample of “Healthy” Mexican Older Adults

The purpose of this study was to describe anthropometric, metabolic, and nutritional characteristics in healthy elderly adults in a primary health care setting. It was conducted through a cross-sectional study of 80 subjects 60 years of age and older. After confirming healthy status, clinical, biochemical, dietetic, and anthropometric evaluations were performed. The findings indicated 22% had anemia, 22% had impaired glucose tolerance, 46% had hypertriglyceridemia, and 51% had hypercholesterolemia. More than 50% had obesity, and almost 80% had a high risk waist circumference measure. Mean energy intake was normal; however, more than 50% of participants did not have adequate intakes of potassium, calcium, magnesium, zinc, folic acid, and vitamins B₁₂ and A. Inadequate food intakes were common. Specific examples are that 16% of the subjects ate no meat/egg, 31% ate no dairy products, 56% ate no legumes, 22% ate no fruits, and 41% ate no vegetables. Additionally, 31% consumed soft drinks. Therefore, we can conclude that elderly people otherwise considered as “healthy” nonetheless had a high proportion of obesity and cardiovascular risk factors. Inadequate dietary patterns were also observed and corresponded with poor micronutrient intake.     

2型糖尿病患者强化降糖治疗的效果和预测指标

为观察2型糖尿病患者强化降糖治疗的预测指标,强化降糖对糖化血红蛋白（HbA1c）、体重、焦虑／抑郁症状、健康状况的影响,以及强化降糖使HbA1c得到改善的患者的特点,研究者收集来自TRIAD（Translating Research into Action for Diabetes）的数据并分析,对起初采用饮食、运动、口服降糖药治疗、HbA1c〉7．2％、持续治疗或强化治疗（开始或增加口服降糖药种类或开始胰岛素治疗）超过18个月的患者进行检查。     

The physiology of membrane digestion. Report 4. Intravascular hydrolysis of starch in the frog

Summary Hydrolysis of soluble starch was studied in the frog: a) during perfusion of the vascular system with starch-sucrose-salt solution and b) under the effect of amylase transported from tissues into the perfusate. A comparative analysis of the rate of hydrolysis in vivo and in vitro showed that amylase in the perfusate was responsible but little for hydrolysis in the vessels. Similar results were obtained in the experiments with the digestive system excluded from perfusion. It may be assumed that an intensive hydrolysis in the vessels may be due to the presence of enzymes fixed on the surface of endothelial cells.(Presented by Academician V. N. Chernigovskii) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 55, No. 5, pp. 25–28, May, 1963     

Hemoglobin Nigeria (alpha-81 Ser replaced by Cys):a new variant associated with alpha-thalassemia

Hematologic evaluation of a Nigerian obstetrical patient disclosed the presence of sickle-cell trait as well as evidence of a hemoglobin alpha- chain abnormality. Hemoglobins containing the variant alpha-chain were isolated by DEAE-cellulose column chromatography, and analysis of the purified alpha-chain demonstrated a ser replaced by cys substitution at alpha-81. The abnormal alpha-chain represented approximately 45% of the total, and hemoglobins containing this alpha-chain appeared to have normal stability and functional properties. In addition to the abnormal hemoglobins that were identified in this patient, she also was found to have persistent microcytosis in the absence of iron deficiency, and the percentage of HbS in her erythrocytes was less than that usually present in individuals with sickle cell trait. These findings, together with a reduced alpha/beta globin synthesis ratio from her peripheral blood reticulocytes, indicated that the presence of alpha-thalassemia trait. Hematologic findings from members of the patients's family suggest that an alpha-thalassemia gene may be linked to that of the structurally abnormal alpha-chain.     

Effect of antiserum against isologous aggregated immunoglobulins on delayed-type hypersensitivity reaction in mice immunized with sheep red blood cells

Injection of mouse antiserum against isologous aggregated immunoglobulins (MAAS) into mice previously receiving 10⁵ sheep red blood cells (SRBC) did not affect the intensity of the delayed-type hypersensitivity (HDT) reaction when tested at the peak of sensitization (4th day), but led to a marked increase in the intensity of the reaction in the later stages (6th day). MAAS completely abolished suppression of HDT observed after sensitization with 5·10⁷ SRBC. Transfer experiments showed that under the influence of MAAS the number of suppressor cells of HDT in the spleen of the sensitized mice was reduced. MAAS had no effect on proliferation of antibody-forming cells or on the intensity of hemagglutinin production, but reduced by 70% the number of rosette-forming cells (RFC) detectable in the spleen at the peak of the primary immune response. The results may be evidence that RFC take part in the suppression of HDT.Laboratory of Immunochemistry, N. F. Gamaleya Institute of Epidemiology and Microbiology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR P. A. Vershilova.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 88, No. 11, pp. 578–580, November, 1979.     

Evaluation of hybridisation on oligonucleotide microarrays for analysis of drug-resistant Mycobacterium tuberculosis

A molecular approach was developed to identify drug-resistant strains of Mycobacterium tuberculosis by means of biochips with oligonucleotides immobilised in polyacrylamide gel pads. The technique was based on multiplex PCR, followed by hybridisation on an oligonucleotide microarray, and detected > 95% of rifampicin-resistant and c. 80% of isoniazid-resistant M. tuberculosis isolates within 12 h. In total, 220 drug-resistant isolates and 131 clinical samples were tested using biochips. The sensitivity and specificity of the developed method were comparable with those of standard bacteriological testing of M. tuberculosis drug resistance.     

Comparative evaluation of the anti-anginal effects of dilzem and corinfar in patients with ischemic heart disease and exertion-induced stenocardia

Antianginal efficiency of dilzem, as compared to placebo, was assessed in 53 patients with angina of effort, functional class II-IV. Repeated bicycle ergometry and 24-hour ECG monitoring were used as objective methods for the assessment of treatment efficiency. Antianginal effect of dilzem (180-300 mg/daily) was compared to that of corinfar (30-60 mg/daily) in 16 patients by a simple blind cross procedure, using placebo. The duration of continuous bicycle ergometric exercise increased by 163 sec. In the presence of dilzem, and by 152 sec. in the presence of corinfar, as compared to the placebo, while the performance volume increased by 1296 and 1188 kgm, respectively (p less than 0.001). Unlike corinfar, dilzem produced a significant drop in heart rate and double product both at rest and during exercise. Both dilzem and corinfar considerably reduced average rate and total duration of painless episodes of myocardial ischemia (p less than 0.05), as evidenced by Holter's monitoring.