The proton acceptor group in the recently described retinal protein, proteorhodopsin has an unusually high pK(a) of 7.1. It was shown that at pH above this pK(a), illumination initiates a photocycle similar to that of bacteriorhodopsin, and the protein transports proton across the cell membrane. Recently it was reported that proteorhodopsin, unlike bacteriorhodopsin, transports protons at pH below the pK(a) of the proton acceptor, and this transport is in the reverse direction. We have investigated the photocycle of proteorhodopsin at such low pH. At pH 5, three spectrally distinct intermediates K, L, and N, and another spectrally silent one, PR', could be identified, but a deprotonated Schiff base containing M-like intermediate, characteristic for proton pumping activity, does not accumulate. All the reactions between the intermediates are close to equilibrium, except the last transition from PR' to PR, when the protein returns to its initial unexcited state in a quasiunidirectional reaction. The electric signal measurements indicate that although charge motions are detected inside the protein, their net dislocation is zero, indicating that contrary to the earlier reported, at low pH no charged particle is transported across the membrane.

No abstract

The circulatory apparatus has as a main function the constant maintaining of the internal environment in all the regions of the organism. The blood is a liquid tissue, being formed of a fundamental substance – plasma and blood cells. Heart is the central organ of the cardiovascular apparatus. The heart muscles have numerous biophysical properties. The cardiac muscle is never tired unless it suffered a pathological process. During the diastole, blood is aspired in the heart and during the systole it is pushed in the big and small circulation. The blood amount pushed from the heart in the vascular system in a certain time represents the blood flow. The biophysical methods are next: we administer a certain substance amount, then its passing speed will depend on its concentration; to apply the calorimetric principles for the measurement of the gastric blood flow; the diagnostic of a chronic peripheral arteriopathy we use the calorimetric method is based on measuring the heat being introduced in a certain amount of water which has known temperature; one of the most often used methods for the evaluation of the use of radioisotopes in the cardio-vascular system is the compartment method. Any attempt to apply biophysics to the life systems involves three stages. First we observe the phenomena and formulate a biophysical description in the form of equations; after to solve the equations. Finally we return to the real life system and interpret this solution in terms of reality, this interpretation may requiew experimental testing.

Low back pain (LBP) is a disease with a high socio-economic and medical impact. Recovery treatment is complex and includes medication (NSAIDs, analgesics, muscle relaxants), physiotherapy and kinesiology. Ultrasound is one of the electrotherapy procedures applied due to its analgesic effects, muscle relaxing properties and massage. The study assesses the evolution of temperature and the number of red blood cells after the application of ultrasound of different intensities and ways. The results are statistically significant for some parameters. Limitations of the study are determined by the relatively small number of study patients, but the results could form the basis of further research.

No abstract

Medical analysis laboratory must establish its own reference intervals depending on the facilities they are working with, the working substances and protocols. These reference intervals must be obtained depending on age groups in order to accurately interpret the results of the analyzes performed. The study is a retrospective one using 3217 data from the electronic archive of the S.C. Vladutiu&Garabedian S.R.L. Clinic in Medias. Total serum calcium was determined by the colorimetric method on the Konelab analyzer. Processing of the collected data was done using the Hoffmann method, considering 5% up to 95% of the values in the database, the values being randomly selected. For comparison, data from the literature was used. In children under 1 year old, it was not possible to calculate the reference intervals since data was insufficient. In the other age groups, reference intervals obtained in the current study were similar to the studied literature. Reference intervals established for calcium can provide important guidance for the reasonable supplementation of this essential element in children.

Hyperdopaminergia has been identified at impulsive or psychotic patients, the polymorphism of COMT or other enzymes that metabolize dopamine could be involved. The deficiencies of the serotoninergic system in suicidal behaviour has been mentioned by many studies that indicate the reduction of 5-HT, 5-HIAA in CSF or 5-HTT polymorphism. Young patients with psychotic or depression symptoms manifest, frequently, aggressive and self-harm behaviour. Besides the association between the young age and the aggressivity of the patients with serious mental disorders, our study shows gender differences and this matter is sustained by hormonal factors. The study was conducted at the Gheorghe Preda Psychiatric Hospital in Sibiu. The study comprises 52 patients aged between 18 and 35 who were diagnosed with the diagnosis of Schizophrenia, Bipolar Affective Disorder, Depressive Episode and Major depressive disorder according to the DSM-5 criteria. Evaluation of the severity of psychiatric and depressive symptomathology were assessed with Brief Psychiatric Rating Scale and Beck Depression Inventory; aggression and self-aggression in the patients with Schizophrenia, respectively with Bipolar disorder, depressive episode and Major depression disorder were assessed with Buss Perry Aggression Questionnaire and Suicide Intent Scale. Regarding the severity of aggression in the young patients from our study (Buss Perry scale score), male gender is higher than female gender: higher percentages in males (35% and 10%) than in females (16 and 0%). Determining aggression in schizophrenia is possible due to COMT polymorphism that lead to impulsivity or psychotic symptoms. The study show a significant positive correlation between the severity of symptoms of schizophrenia and aggression. From the analysis of the severity of depression in young patients (SIS score) it is noted that its severity is higher in the female gender. Women had higher scores of moderate depression (58%) and severe (26%) than men (37 and 25%, respectively). This relationships could be possible due to the polymorphism of the gene encoding the 5-HTT serotonin transporter related with serotonin deficiency.The study do not show a significant positive correlation between the severity of the depressive symptomatology and the degree of the suicide intent.

Magnesium is an essential nutrient for the living organisms and plays an important part in the prevention and treatment of many diseases. It is an enzymatic cofactor for more than 300 reactions. Magnesium is essential for regulating blood pressure, muscle contraction, cardiac excitability, insulin metabolism, vasomotor tonus. Studying the way in which serum magnesium concentration varies in children and adolescents in the Sibiu area according to the reference intervals we especially set for this area. The study is a retrospective one, using approximately 4900 data from the archives of the Medical Analysis Laboratory within the Sibiu Pediatric Clinical Hospital. Serum magnesium was dosed using the Konelab Prime 30i analyser. The data from the literature was used to compare the results. The reference ranges obtained in the current study were similar to the literature studied. The percentage of patients with magnesium concentration outside the reference ranges was roughly equal for all age groups. The difference was between 1 month and 2 year-old children with very few deviations from the reference range. The results of our study reflect more accurately the real reference range for the population in the Sibiu area, helping clinicians to establish a diagnosis as quickly and accurate as possible. These results were not significantly different from the literature studied.