Fabrication of [001]-oriented tungsten tips for high resolution scanning tunneling microscopy.

The structure of the [001]-oriented single crystalline tungsten probes sharpened in ultra-high vacuum using electron beam heating and ion sputtering has been studied using scanning and transmission electron microscopy. The electron microscopy data prove reproducible fabrication of the single-apex tips with nanoscale pyramids grained by the {011} planes at the apexes. These sharp, [001]-oriented tungsten tips have been successfully utilized in high resolution scanning tunneling microscopy imaging of HOPG(0001), SiC(001) and graphene/SiC(001) surfaces. The electron microscopy characterization performed before and after the high resolution STM experiments provides direct correlation between the tip structure and picoscale spatial resolution achieved in the experiments.

Atomic row doubling in the STM images of Cu(014)-O obtained with MnNi tips.

We report on scanning tunneling microscopy studies of the Cu(014)-O surface using MnNi tips. Remarkably, the results show a regular apparent doubling of surface atomic rows in the {110} direction. A qualitative explanation of this feature based on tight binding and density functional theory calculations of the electronic structure of the tip is presented. Double imaging of the same atom by different legs of dyz orbital could be the reason for the observed doubling. The orientation of the orbital is determined by the O-Mn crystal field.

[Several hormonal indices during hemofiltration in patients with acute kidney failure]. / Nekotorye gormonal'nye pokazateli pri gemofil'tratsii u bol'nykh s ostroi pochechnoi nedostatochnost'iu.

AIM: To study hormonal aspects of hemofiltration (HF) in acute renal failure (ARF). MATERIAL AND METHODS: Hydrocortisone (HC), thyroxine (T4), triiodothyronine (T3), TSH, thyrocalcitonine (TC), PTH, insulin (I), C-peptide (CP), STH, beta-endorphine (BE) were examined for plasma content, elimination with filtrate, sifting rate, filtration clearance in 29 patients with oliguric ARF (18 males and 11 females) aged 12-62 years. 19 patients underwent intermittent HF (rate 145.2 +/- 9.2/27-260/ml/min, volume 1.02 +/- 0.20/0.45-1.43/). 10 patients received continuous HF (rate 25.9 +/- 2.3 l/day or 0.36 +/- 0.05/0.17-0.95/). The hormones were measured with radioimmunoassay. The results were processed with variate statistics using Student's criterium. RESULTS: Oliguria was associated with high plasma levels of HC, PTH, TC, I, CP; normal levels of TSH and STH, low ones of T4, T3 and BE. Intermittent HF led to an increased plasma concentrations of HC, T4, I, CP, decreased one of PTH, while TC, TSH, STH and T3 remained unchanged. The filtration rate of the hormones was different. The elimination was greatest for HC, T4, T3, BE. Concentration of the former three in the filtrate surpassed that in blood plasma. CONCLUSION: Besides intensive elimination of the hormones with low molecular mass (HC, T4, T3), HF causes elimination of appreciable quantities of BE, PTH, I, CT and, probably, other peptide hormones. Plasma levels of hormones did not reflect their elimination with filtrate.

[Complement system during hemofiltration in patients with multiple organ failure]. / Sistema komplementa pri gemofiltratsii u bol'nykh s poliorgannoi nedostatochnost'iu.

Nine patients (8 men and 1 woman) were treated. Sepsis was diagnosed in 7 of them. All patients were subjected to forced ventilation of the lungs, 6 were in need of inotropic support. The severity of clinical status was 31 +/- 0.8 according to APACHE II score. One patient survived. The main method of substitute renal therapy (SRT) was permanent hemofiltration with spontaneous arteriovenous perfusion. The results indicate manifest depletion of the complement system augmenting with the progress of multiple organ failure (MOF). Extracorporeal perfusion in SRT had no additional negative effects on the complement system damaged by disease. Nonselective penetration of individual complement fractions into the filtrate in the course of perfusion was noted. Therefore, the complement system is severely damaged in patients with MOF; it can modulate the SRT because of penetration of its individual fractions.

[Tumor necrosis factor-alpha kinetics during renal replacement therapy in patients with sepsis and multiple organ failure]. / Kinetika faktora nekroza opukholi al'fa pri zamestitel'noi pochechnoi terapii u patsientov sepsisom i s poliorgannoi nedostatochnost'iu.

Peptide TNF-alpha (tumor necrosis factor alpha) secreted by monocytes and resident macrophages is a key proinflammatory mediator. It can generate response systemic inflammation leading to shock and polyorganic insufficiency. Elimination of circulating TNF-alpha is pathogenetically perspective in respect to therapy of septic shock. Plasma level of TNF-alpha and its elimination with the filter/dialysate was traced in 23 patients with sepsis and polyorganic insufficiency receiving substitute renal therapy (continuous hemodiafiltration, intermittent hemodialysis) for acute renal failure. Sepsis and polyorganic insufficiency was associated with elevated plasma levels of TNF-alpha correlating in many cases with the disease severity. TNF-alpha was for the most part eliminated with the filter/dialysate. The degree of this elimination was related to the technique of blood perfusion and characteristics of the procedure.

[Transient synovitis of the hip joint in children]. / Tranzitornyi sinovit tazobedrennogo sustava.

The character of the clinical course and outcome of transitory synovitis of the hip joint (TSHJ) in 89 patients have confirmed the working hypothesis concerning the role of viruses in the appearance of TSHJ. Active treatment of patients including the paracentetic decompression of the damaged hip joint abolishes the excessive intra-articular pressure, pain syndrome, prevents disturbances of blood circulation of the femur head.

[The neurology of terminal states]. / Nevrologiia terminalnykh sostoianii.

The paper gives a theoretical justification of CNS abnormality developing in patients who have a history of critical and terminal states, including clinical death. The most significant abnormality is that which is termed posthypoxic and/or postresuscitation encephalopathies whose nature has not been elucidated particularly at the cellular and molecular levels. It is emphasized that this involves brain abnormalities, which is a sequela of hypoxia or ischemia of systemic origin, rather than primary brain damages. In some patients who have sustained a severe hypoxic episode of any nature and recovered their psychoneurological status ever rapidly and rather fully, there may be an abrupt progressive deterioration of their neurological status in some days or months, which results in death or grave irreversible disability. It is concluded that not only do reparative and compensatory processes occur, but also there are phenomena of progressive degenerative changes in a primarily successfully resuscitated person or experimental animal in the central nervous system in the postresuscitation period. A classification of psychoneurological disorders in patients in the early postresuscitation period has been made and ways of their prevention or alleviation have been indicated.

[The protein components of the acid-soluble fraction of normal human blood plasma and in peritonitis patients]. / Belkovye komponenty kislotorastvorimoi fraktsii plazmy krovi cheloveka v norme i u bol'nykh peritonitom.

Samples of acid-soluble blood plasma fractions from 10 healthy donors and 12 patients with peritonitis have been fractionated, using the techniques of vertical electrophoresis in polyacrylamide gel and high pressure liquid chromatography. Three basic protein-containing components with the molecular mass 43, 30 and 14 kD have been identified in samples of donor blood plasma. In peritonitis there is an increase in the level of some fractions present in acid-soluble fractions of donor blood plasma and the generation of new protein-containing acid-soluble components. A band corresponding to a component with a molecular mass 64 kD and a wide band in the range of 9-14 kD have been registered. The treatment of donor blood with trypsin generates some components characteristic of acid-soluble blood plasma fraction of patients with peritonitis. The authors believe that increased proteolytic activity is one of the factors responsible for qualitative and quantitative changes in acid-soluble blood plasma fraction in peritonitis.

[The anesthesiological-resuscitation aspects and the medical problems of catastrophes]. / Anesteziologo-reanimatsionnye aspekty i problemy meditsiny katastrof.

Anaesthesiological and resuscitation service is a special component of disaster medicine. It is of paramount importance in LSFA (life-supporting first aid) training of the lay public. Lack of knowledge and inadequate application of LSFA are estimated to increase the mortality rate of disaster victims by 40%. The paper discusses quantity and quality of anaesthesiological and resuscitation aid delivered immediately at the disaster scene, during triage before and after evacuation, during transportation. Much attention is devoted to pain management and infusion therapy performed at the disaster scene and during transportation.

[A computer system for analysis and presentation of the results of studies of the immune status of patients with a profile of resuscitation]. / Komp'iuternaia sistema analiza i otobrazheniia rezul'tatov issledovaniia immunologicheskogo statusa u bol'nykh reanimatsionnogo profilia.

Logical principles for the use of computer technology in the assessment of medical information in intensive care units are outlined. A computer system for the assessment of the results of immune status studies has been presented. The potentials are demonstrated to form the data bank with realization of precedent search function, presentation of information with the help of computer graphics and calculation of highly informative secondary indexes on the basis of primary ones.

[Methods of plasty in meningocele in children]. / Sposoby plastiki pri spinnomozgovykh gryzhakh u detei.

The authors describe their original method of fascio-aponeurotic plasty of the bone defect in meningocele in children. The method was used in 25 children and gave positive results.

[Effect of blood transfusion therapy on the course of suppurative septic diseases in children]. / Vliianie gemotransfuzionnoi terapii na techenie gnoino-septicheskikh zabolevanii u detei.

The authors have studied the influence of different variants of hemotransfusion therapy on the course of pyo-septic diseases in 189 children aged from 1 month to 14 years. Positive effects of blood transfusions on the parameters of the peripheral blood, homeostasis and coagulating system as well as the stimulating effect on the bone-marrow blood formation and the immune defense system were demonstrated.