Psychological care reflecting the specifics of the course of viral infection in SARS-CoV-2 oncological patients with oxygenation disorder - a case series.

BACKGROUND: During the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic, patients treated with acute coronavirus disease 2019 (COVID-19) in intensive care units (ICU) have suffered from neuropsychiatric complications such as anxiety, depression, and confusion. Conditions related to the environment have the potential to worsen these symptoms. In combination with virus-dependent neuroinflammation, they form a "toxic" mixture. Discussion and planning strategies for providing psychological care in the ICU during the pandemic have revealed a great current challenge. CASE SERIES: We share our experience concerning psychological interventions for oncological patients with oxygen saturation depletion. Our observation of two SARS-CoV-2 patients suggests a close time-related association between the increase in inflammatory markers interleukin 6 (IL-6) and C-reactive protein (CRP) and intensive anxiety in the fast development of breath shortening in acute COVID-19 infection due to brain hypoxia and potential neuroinflammation. CONCLUSION: As cytokine IL-6 regulates induction of CRP gene expression, the changes in IL-6 concentrations associated with anxiety symptoms and breath shortening in the observed cluster can be detected hours earlier than changes in CRP levels, with a diagnostic implication for the clinicians. The SARS-CoV-2 patients with oncological diseases treated in our ICU asked for personal bedside contact with clinical psychologists, considered it irreplaceable and reported this psychological care as beneficial.

[Mathematical simulation of stem/cement/bone mechanical interactions for Poldi-Cech, CF-30, MS-30 and PFC femoral components]. / Výpoctové modelování mechanických interakcí dríku Poldi-Cech, CF-30, MS-30 a PFC s cementem a kostní tkání

PURPOSE OF THE STUDY The mid-term longevity of femoral components varies considerably, with some showing failure due to early aseptic loosening. Since the hip joint is subject to heavy mechanical loads, it can be assumed that the mechanical interaction of the implant, bone cement and femur will play a key role in the resultant reliability of an arthroplasty. This study was designed to examine this mechanical interaction in four femoral components different in construction (Poldi-Cech, CF-30, MS-30 and PFC) using mathematical simulation. MATERIAL AND METHODS Four stem/cement/femur 3-D mathematical models, comparable in quality, infolving the Poldi-Cech, CF-30, MS-30 and PFC stems, respectively, were constructed. A 3-D model for each stem was created according to its real, middle-size femoral component. Each 3-D model of the cement mantle corresponded in shape to the mantle of the appropriate real stem, with its thickness based on the recommended values of 4-7 mm in the proximal and 1-3 mm in the distal part, and with the cement mantle reaching as far as 10 mm distal to the femoral stem tip. For simplicitys sake the outer surface of the cement mantle was simulated as smooth. A 3-D model involving the proximal epiphysis and the metaphysis of a femur was reconstructed, based on a series of CT cross-sections obtained periodically at 10.5-mm and 2.5-mm distances. The sten/cement/femur model with the MS-30 stem also included a centraliser. The mechanical interaction of the stem, bone cement and bone tissue was examined by means of mathematical stimulation using ANSYS 5.7 software based on finite element analysis. RESULTS For the sake of simplicity, only two key parameters are presented, namely, contact stress at the stem-cement interface and equivalent deformation in the stem/cement/femur system. The least satisfactory stress loading was in the CF-30 stem whose sharp edges showed the values of contact stress about six-times higher than on the mid-medial portion of the stem, with the sharp edges behaving as stress concentrators. A satisfactory stress loading was found in Poldi-Cech, MS-30 and PFC stems, in which contact stress was evenly distributed along the whole lenght of the stem and the values at the edges and on the midmedial portion did not differ much. DISCUSSION The distribution of contact stress is one of the most important factors for the long-term longevity of implants. It was found least satisfactory in the CF-30 stem whose sharp edges act as stress condenser adversely affecting not only the stemcement interface, but also the resultant stress distribution within the femur. The most satisfactory results of stress distribution were recorded in the Poldi-Cech and MS-30 stems. The PFC stem also responded satisfactorily to the simulated stress loading. However, on loading whose substantial part would be torsion, the stems circular or oval cross-section could interfere with rotation stability of the implant; but this was impossible to detect by the mathematical simulation used in this study. CONCLUSIONS The results presented here show that, in the Poldi-Cech, CF-30, MS-30 and PFC femoral stems, a good agreement was achieved between the results of their clinical application and those of mathematical modelling of their mechanical properties. It can be concluded that mechanical interaction among the femoral stem, cement mantle and bone tissue plays the key role in the long-term longevity of such an implant. Key words: Poldi-Cech, CF-30, MS-30, PFC, mechanical interaction, contact stress.

[Early aseptic loosening of the CF 30 femoral stem]. / Predcasné aseptické uvolnování dríku CF 30.

PURPOSE OF THE STUDY: The CF 30 stem in combination with a cementless acetabulum was used at the First Department of Orthopedic Surgery in Brno in the years 1994 to 1995. From the second year following implantation, aseptic stem loosening was recorded. In order to find explanation of this early loosening, the authors, in cooperation with the Institute of Solid Mechanics, Mechatronics and Biomechanics, carried out the stress-strain analysis in a model system. MATERIAL: Eighty patients (31 men and 49 women) received a cemented CF30 femoral component in 1994. Of them, 16 patients underwent revision arthroplasty, three died of causes unrelated to the surgery, and four were lost to follow-up. METHODS: The final clinical and radiographic check-up was carried out in 2001. The results of a comprehensive examination were available in 57 patients with a CF30 stem. The patients were evaluated on the basis of the Harris hip score and anteroposterior radiographs of the hip. X-ray films obtained immediately after surgery and those taken at regular intervals during follow-up were compared. The following characteristics were noted: translucent lines in individual zones along the stem at the cement-bone interface; osteolysis, i. e., non-linear translucent areas, at least 5 mm long, at the cement-bone interface; and subsidence of the femoral component, i. e., migration of the stem distal to the tip of the greater trochanter. RESULTS: The CF 30 stem survival curve showed that aseptic stem loosening occurred from post-implantation year 2, and increased during the following years. At 6 years and 6 months, a total of 16 patients underwent revision surgery, involving reimplantation in 14 and implant removal in 2 patients. DISCUSSION: Potential causes of aseptic loosening: Polyethylene wear.However, no acetabular loosening was found in this group, although acetabular components are reported to become loose more often than femoral components. By comparison of the stem survival curves for Poldi and CF 30 stems it appeared that, at 6 years and 6 months, the Poldi stem survival curve showed better results. Matt surface finish of the stem. However, the link between the CF 30 stem and cement was so strong that, in all 16 revised hips, the stem was removed together with nearly a complete cement mantle. The authors therefore dismiss this as a cause. Also, in the remaining cases of CF 30 aseptic loosening, which had not been revised, radiographic evidence suggested loosening between bone and cement. The authors did not find any movement of the CF stem in its cement mantle. The stem always fitted in with the cement mantle. Erroneous surgical technique or cementing was unlikely. The procedures were performed by experienced orthopedic surgeons who used the second-generation cementing technique. In patients with a Poldi stem, the first-generation cementing method was used and the proportion of aseptic loosening at 6 years of follow-up was only 4 %. In contrast, loosening in patients with the CF 30 stem was 20 % at 6 years and 6 months postoperatively. Shape of the CF 30 stem with the intention to find a relationship between stem shape and its early aseptic loosening, the authors started cooperation with the Institute of Solid Mechanics, Mechatronics and Biomechanics at the Faculty of Mechanical Engineering, Brno University of Technology. Using the method of finite elements, they carried out the stressstrain analysis in a model system. Stress at the cement-bone interface in the CF 30 stem was higher than in the Poldi stem, and this difference was statistically significant. The authors believe that the more frequent loosening found in patients with the CF 30 stem can be accounted for by its shape. CONCLUSIONS: The survival curve for the CF 30 femoral stem did not show good results, and therefore this stem is not recommended for implantation. The authors suggest that a more frequent early aseptic loosening of CF 30 stems may have been caused by its unsuitable shape.

Understanding physical activity intention in Canadian school children and youth: an application of the theory of planned behavior.

The purpose of this study was to investigate the efficacy of the theory of planned behavior in predicting physical activity intention in a nationwide sample of Canadian children and youth. The study sample consisted of participants from Grades 3, 5, 8, and 11 from schools across Canada. School participation was determined by means of a randomly stratified sample design. Results show that the direct measures of the theory of planned behavior explained 47% of the variability in the measure of physical activity intention. In addition, notable differences in the relative contributions of the predictor variables of attitude, subjective norm, and perceived behavioral control were found across grade and grade-by-gender subgroups. The present study provides evidence that in a population of children and youth the determinants display a pattern of change developmentally.

Modified radical vulvectomy without lymphadenectomy under local anesthesia in medically compromised patients.

INTRODUCTION: Our objective was to review our experience with vulvar cancer treated with modified radical vulvectomy without lymphadenectomy under local anesthesia and sedation. METHODS: A retrospective review of surgical case lists revealed five patients who underwent modified radical vulvectomy without lymphadenectomy under local anesthesia with sedation. All patients had significant medical diseases which precluded regional or general anesthesia. Modified radical vulvectomy was performed in standard fashion under sedation and local anesthesia. Inguinal lymphadenectomy was not performed. RESULTS: Median operative time was 1.5 h and median blood loss was 100 cc. Median diameter of tissue resected was 5 cm and median depth was 5 cm. Median length of hospital stay was 4 days. No patient complained of pain during the operative procedure. At a median follow-up of 2.5 years, there has been one local recurrence. CONCLUSION: Five patients with symptomatic vulvar cancer who were not candidates for regional or general anesthesia underwent modified radical vulvectomy without lymphadenectomy under local anesthesia with sedation. The procedure was well-tolerated and produced minimal morbidity and adequate short-term local control.

[Treatment of fractures of the lower cervical spine (C3-C7)]. / Liecba zlomenín dolnej casti krcnej chrbtice (C3-C7).

Spinal surgery dealing with reparation of injury consequences by stabilisation implantates is a relatively new surgical branch. The experience and results at individual departments in Slovakia in this field differ significantly as to their qualitative degree. The Trauma Surgery Department IVZ in Bratislava and the National Rehabilitation Center in Kovácová cooperate since 1989 in a mutual spinal programme. 177 out of 189 patients survived after undergoing a surgical treatment due to the injury of the lower cervical spine performed from 1988 to 1994. 68 patients (Frankel A, B, C) were included into the spinal programme. The authors present the therapeutical results evaluated according to morphologic, neurologic, functional and subjective criteria. The most frequently used stabilizing method is the so-called method of Caspar and the technique of Morscher, the latter being less frequently applied. Both methods are fully secure, causing minimal blood loss, perfectly stable as to the angle and axis. Both techniques enable a sufficient approach to the decompression of the spinal cord. Since they do not demand any additional external rigid fixation, they are excellently tolerated by patients and only minimally restrict movement. (Tab. 2, Fig. 4, Ref. 8.)

The synthesis of highly phosphorylated nucleotides, RNA and protein by Streptomyces aureofaciens.

During the sudden decrease in RNA synthesis in Streptomyces aureofaciens, i.e. around the 6th hour of cultivation, synthesis of adenosine and guanosine tetraphosphates and pentaphosphates begins. The synthesis of these nucleotides is highest during the onset of chlortetracycline production, around the 20th hour of cultivation and continues. During this phase of growth of S. aureofaciens, RNA and protein synthesis are reduced by about one order of magnitude as compared to the rate which can be observed at the beginning of cultivation, but the synthesis is not inhibited by exogenous CTC.

Colonial growth and ramihyphin A-induced changes in cell walls of Neurospora sitophila.

Colonial growth of Neurospora sitophila phenotypically induced by ramihyphin A is accompanied by marked changes in the contents of DNA, RNA and proteins in the mycelium, and in the relative proportion of hexoses in cell wall hydrolysates. The glucosamine/glucose ratio is also characteristic for colonial growth. X-ray analysis of cell walls showed that ramilhyphin A suppresses the crystalline arrangement of chitin in cell walls. A combination of microbiological, biochemical and physico-chemical methods yielded a general picture of the changes accompanying the colonial growth of Neurospora sitophila.