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Graphene is a new, advanced material with many possible applications in basic and clinical medicine, electronics and automation. Graphene compounds can be successfully used as an integral part of drug delivery systems, in the construction of transistors, polar processors, touch screens, solar cells and in the production of materials for the manufacture of personal protective equipment, i.e. products and equipment intended to protect the health and life of users. The literature review presented in this paper concerns physical and mechanical properties of composites containing graphene or its structure as well as methods of obtaining polymer, metallic and ceramic composites doped with graphene structures. Data analysis of the potential use of graphene and its composites in personal protective equipment such as monitoring sensors, clothing and security equipment such as ballistic armor, helmets and protective clothing were also reviewed and summarized.

The incorporation of biopolymers, such as chrome shavings and buffing dust, into rubber blends makes it possible to obtain biodecomposable collagen-elastomer materials with good utility properties. It is the presence of a biopolymer in multicomponent polymeric materials that facilitates enzymatic hydrolysis and results in biodecomposition through the loss of cohesiveness and polymer scattering. The undertaking of such original studies was justified by the benefits resulting from a new generation of polymeric materials and the need for a solution to the problem of growing amounts of wastes by waste management in the tanning industry. In this study, the effect of a mixture of chrome shavings and buffing dust on the properties of nitrile rubbers was examined. The dust and shavings, in a 1:1 proportion, were mixed with 5 parts by weight of zinc oxide and, in this form, was added to the rubber blends. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010 [ABSTRACT FROM AUTHOR]

The elastomeric anti-trauma pad (EA-TP) based on shear thickening fluid (STF) has been developed. Dynamic oscillatory shear experiment was conducted at constant strain amplitude of 5%. STF composed of 25% of volume fraction of 7 nm Fumed Silica, dispersed in polypropylene glycol with molar mass 400 gmol−1 shows elastic properties in entire investigated range of the frequency. Ballistic tests of EA-TP with 7.62 mm × 39 mm PS bullets were performed according to the PN-V-87000:2011 standard. The studies revealed about 60% reduction of the average backface signature depth (BSD) for the EA-TP, when compared to the nowadays commonly used soft insert. The ATR-FTIR analysis confirmed slight impact of the elevated temperature and air (oxygen) on the chemical degradation of the EA-TP surface. The UV-VIS spectroscopy has allowed to notice colour deviation of the aged samples towards green and yellow, as well as lack of dye resistance to accelerated aging process. Thermographic analysis has shown no visible changes of the EA-TP surface and sub-surface during accelerated aging process. The aforementioned small changes on the surface of EA-TP did not affect the ballistic properties of composite armour. EA-TP insert maintains ballistic properties after accelerated aging process which was simulating the period of 6 years according to ASTM F1980 – 07:2002 standard.

The aim of this study was to test the usefulness of magnetron sputtering technology to produce coatings on selected elements of a firefighter’s helmet to protect against infrared radiation (PN-EN 171 standard). The scope of research includes testing the deposition produced via magnetron sputtering of metallic and ceramic coatings on plastics, which are used to manufacture the components comprising the personal protection equipment used by firefighters. The UV-VIS, NIR used to research the permeation coefficients and reflections for light and infrared light and the emission spectrometry with ICP-AES used for the quantitative analysis of elements in metallic and ceramic coatings. Microstructural and micro-analytical testing of the coatings were performed using scanning electron microscopy (SEM). Measurements of the chemical compositions were conducted using energy-dispersive X-ray spectroscopy (EDS). The hardnesss of the coatings were tested using a indentation method, and the coating thicknesses were tested using a ellipsometry method.

Our study focuses on molecular rotors with fast-moving rotators and their potential applications in the development of new amphidynamic crystals. Steroidal molecular rotors with a dipolar fluorine-substituted phenyl group as the rotator were synthesized and characterized. Three different rotors were investigated with varying numbers of fluorine atoms. A comprehensive analysis was performed using vibrational spectroscopy (Raman, FT-IR), electronic circular dichroism (ECD), and dielectric response to understand the behavior of the investigated model rotors. The results were supported by theoretical calculations using Density Functional Theory (DFT) methods. The angle-dependent polarized Raman spectra confirmed the crystallinity of the samples. Nearly frequency and temperature-independent permittivity suggest low-frequency librational motion of stators. An in-depth analysis of ECD spectra revealed high conformational flexibility in solution, resulting in low ECD effects, while in the solid-state with restricted rotation, significant ECD effects were observed. These findings shed light on the conformational behavior and potential applications of the studied steroidal molecular rotors., (© 2024 Wiley‐VCH GmbH.)

Background: Available statistical data from 2015 show that 28% of pregnancies in developed countries end in cesarean section (CC). Discomfort associated with the scar after surgery is a common complication., Objectives: This study aimed to evaluate the changes in the structure of the cesarean scar after the application of a scheme of manual therapy., Material and Methods: The study included 15 women in the treatment group (TG) and 15 in the control group (CG). The scars were evaluated twice at 5-week intervals with the use of quantitative scales: the Vancouver Scar Scale (VSS), the Manchester Scar Scale (MSS) and the Patient and Observer Scar Assessment Scale (POSAS). During each examination, the scar was compared, using the specified criteria, to the physiological skin, i.e., the tissues directly bordering the incision. During therapy, 8 manual techniques were used during a 4-week program consisting of 30-minute sessions 3 times per week., Results: Patients in the TG showed a statistically significant improvement in all of the analyzed characteristics of the scar. A statistically significant difference was also observed between the results obtained during the 2nd examination (after the therapy) in the TG and the CG., Conclusions: As a result of the therapy, the condition of the scar in the TG significantly improved. Onerous scar-related symptoms were alleviated. The vascularity, hyperpigmentation and distortion of the scar were reduced. The elasticity and pliability of the scar increased, and the height of the scar decreased. The texture, finish and contour of the scar improved. Obtained results suggest that manual therapy of the scar after CC should be a part of the treatment in women during the postpartum period.

Importance: Identifying research priorities of patients with concussion, their caregivers, and their clinicians is important to ensure future concussion research reflects the needs of those who will benefit from the research., Objective: To prioritize concussion research questions from the perspectives of patients, caregivers, and clinicians., Design, Setting, and Participants: This cross-sectional survey study used the standardized James Lind Alliance priority-setting partnership methods (2 online cross-sectional surveys and 1 virtual consensus workshop using modified Delphi and nominal group techniques). Data were collected between October 1, 2020, and May 26, 2022, from people with lived concussion experience (patients and caregivers) and clinicians who treat concussion throughout Canada., Exposures: The first survey collected unanswered questions about concussion that were compiled into summary questions and checked against research evidence to ensure they were unanswered. A second priority-setting survey generated a short list of questions, and 24 participants attended a final priority-setting workshop to decide on the top 10 research questions., Main Outcomes and Measures: Top 10 concussion research questions., Results: The first survey had 249 respondents (159 [64%] who identified as female; mean [SD] age, 45.1 [16.3] years), including 145 with lived experience and 104 clinicians. A total of 1761 concussion research questions and comments were collected and 1515 (86%) were considered in scope. These were combined into 88 summary questions, of which 5 were considered answered following evidence review, 14 were further combined to form new summary questions, and 10 were removed for being submitted by only 1 or 2 respondents. The 59 unanswered questions were circulated in a second survey, which had 989 respondents (764 [77%] who identified as female; mean [SD] age, 43.0 [4.2] years), including 654 people who identified as having lived experience and 327 who identified as clinicians (excluding 8 who did not record type of participant). This resulted in 17 questions short-listed for the final workshop. The top 10 concussion research questions were decided by consensus at the workshop. The main research question themes focused on early and accurate concussion diagnosis, effective symptom management, and prediction of poor outcomes., Conclusions and Relevance: This priority-setting partnership identified the top 10 patient-oriented research questions in concussion. These questions can be used to provide direction to the concussion research community and help prioritize funding for research that matters most to patients living with concussion and those who care for them.

The aim of this paper is to present the results of research on attitudes towards rape conducted in a group of 850 adult Poles, including 505 women, 310 men and 35 non-binary people, and to analyze their selected correlates: rape myth acceptance, right-wing authoritarianism and rape empathy. Non-binary people have only recently been included in research as a distinct group and little information can be found in the literature on the characteristics of their attitudes towards social problems. Therefore particular attention was paid to comparing the attitudes towards rape of non-binary people with those of women and men. In analyzing the results, the authors took into account the current socio-political situation in Poland. The results indicate that attitudes toward sexual aggression are related to the type of gender identification. The most positive attitudes towards rape victims among the groups participating in the research are held by non-binary people. Furthermore, attitudes towards rape are determined by rape myths, right-wing authoritarianism and empathy for victims of rape., (© The Author(s) 2022.)

Sodium-glucose cotransporter 2 (SGLT2) inhibitors are a new class of antidiabetic drugs, acting by inhibiting the reabsorption of glucose in the kidneys. They turned out to improve cardiovascular and renal outcomes not only in patients with type 2 diabetes but also in nondiabetic patients. At present, they are more and more widely used in patients without diabetes. Since there were concerns that SGLT2 inhibitors may increase fracture risk in diabetes, the aim of the study was to examine the effect of dapagliflozin and canagliflozin on the musculoskeletal system of nondiabetic, healthy rats. The experiments were carried out on mature female rats, divided into the control rats and rats treated with dapagliflozin (1.4 mg/kg p.o.) or canagliflozin (4.2 mg/kg p.o.) for 4 weeks. Serum bone turnover markers, skeletal muscle strength and mass, bone mass, density, histomorphometric parameters and mechanical properties were determined. Administration of the drugs did not affect the skeletal muscle mass and strength. There was no effect on serum bone turnover markers, and bone mass and composition. However, administration of both drugs resulted in disorders of cancellous bone microarchitecture and worsening of bone mechanical properties. In conclusion, both SGLT2 inhibitors unfavorably affected the skeletal system of healthy rats., Competing Interests: Conflict of interest statement The authors declare no conflict of interest., (Copyright © 2022 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

Nowadays there are numerous studies on the occurrence of cognitive dysfunction in late-life depression (LLD). The role of executive dysfunctions in the psychopathology of depression is particularly emphasized and needs further examination. The aim was to assess cognitive functions and their relation to depressive symptoms in elders with LLD, previously depressed, and patients without the history of depressive episodes. The study consisted of 824 older adults who underwent a neuropsychological evaluation (97 currently depressed, 114 previously depressed and 613 patients without the history of depressive episodes). LLD patients performed poorer in ACE-III and AVLT and poorer in TMT-B than those previously depressed and never depressed. The LLD group also performed significantly poorer than the previously depressed on Digit Span Forward. Results of a multiple regression analysis indicated that performance on measures of executive functioning was associated with depression severity in LLD (β =.227, P =.024). The results of this study suggest that executive functions are the most impaired in the elderly with LLD. Furthermore, there is a relationship between executive dysfunction and the severity of depression in LLD. Executive dysfunction appears to be the core neurocognitive deficit in LLD.

Background and Objective: Dedifferentiated liposarcoma (DDLPS) is characterized by non-lipogenic sarcoma fields coexisting with adipocyte-rich well-differentiated areas. Amplification of the 12q13-15 region includes the MDM2 and DDIT3 genes. MDM2 amplification is considered a genetic hallmark of DDLPS, while DDIT3 is typically rearranged in myxoid liposarcoma. Recent studies showed that DDIT3 amplification is associated with myxoid liposarcoma-like (LPS-like) morphology in DDLPS. Our study aimed to evaluate the status of MDM2 and DDIT3 by FISH in DDLPS and correlate it with MLPS-like features., Material and Methods: Six patients with MLPS-like morphology DDLPS were investigated pathologically, immunohistochemically, and genetically. The control groups of patients with classical DDLPS morphology and well-differentiated liposarcoma (WDLPS) were established and molecularly assessed as well. Fluorescence in situ hybridization (FISH) used in routine diagnostics was performed to determine the status of MDM2 and DDIT3 genes., Results: The patient's mean age was 64 (range from 43 to 85 years) with a 5:4 male to female ratio. Tumors were localized retroperitoneally (15) and extra-retroperitoneally (3). All cases demonstrated amplification of the 12q15 region containing MDM2 gene and co-amplification of the 5' DDIT3 FISH Probe representing DDIT3 telomeric tag. However, we did not find the relation of myxoid LPS-like morphology with DDIT3 amplification as previously reported., Conclusions: The biopsy material from DDLPS with myxoid areas can be misclassified as myxoid liposarcoma. Indeed, according to the histological image, DDIT3 status may be evaluated first. In these cases, we show that the DDIT3 telomeric tag amplification assessed by FISH, is a common, nonspecific feature, which is also found in classical DDLPS and WDLPS. Therefore, we believe that co-amplification of DDIT3 and MDM2 may be considered a spectrum of the 12q13-15 region amplification due to the specification of FISH methodology., (Copyright © 2021 Elsevier GmbH. All rights reserved.)

Case Presentation: A 35-year-old woman without past medical history sought treatment for fatigue and dry cough of 3 weeks' duration. Basic laboratory tests revealed severe anemia. She had no history of bleeding, hemoptysis, dyspnea, or fever. The patient was admitted for RBC transfusion and more extensive diagnostics., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)

Properly designed molecular rotors with sizable stators and a fast-moving rotator could provide efficient building blocks for amphidynamic crystals. Herein, we report the synthesis of steroidal compounds 1 , 2 , and 3 and their deuterated analogues 1D , 2D , and 3D envisioned to work as molecular rotors. The obtained compounds were characterized by attenuated total reflection-infrared, Raman, and circular dichroism (CD) spectroscopy measurements. The interpretation of spectra was supported by theoretical calculations using density functional theory methods. The analysis of the most characteristic bands confirmed different molecular dynamics of the rotors investigated. Angle-dependent polarized Raman spectra showed the crystallinity of some samples. Electronic CD (ECD) spectra of compounds 1-3 and their relevant deuterated analogues 1D-3D are identical. The increase of the band intensity with lowering the temperature shows that the equilibrium is shifted to the thermodynamically most stable conformer. ECD spectra simulated at the TDFFT level of theory for compound 3 were compared with experimental results. It was proved that conformer 3a , with a torsion angle of +50°, exhibits the best agreement with the experimental results. Simulated vibrational CD and IR spectra for conformer 3a and its deuterated analogue 3Da also display good agreement with experimental results. In light of our comprehensive investigations, we evidenced that steroidal compounds 1 , 2 , and 3 can work as molecular rotors.

Objective: Introduction: Cognitive limitations are a serious health and social problem, which concerns elderly people. Effective prevention and treatment of cognitive dysfunction is one of the challenges of modern medicine. There is not enough consistent data in the literature to indicate to indicate the relationship between various clinical and demographic factors with cognitive functioning in different age ranges. The aim: To analyze clinical and demographic predictors of mild cognitive impairment by age group., Patients and Methods: Material and methods: The analysis included 817 participants (669 with normal cognitive function and 148 people with MCI). The evaluation of the level of depressive symptoms was measured by the Short Form Geriatric Depression Scale. All participants were screened for cognitive functioning using the Mini-Mental State Examination and Addenbrooke's Cognitive Examination-III. Different cognitive domains were evaluated with different neuropsychological tools: the Rey Auditory Verbal Learning test, Clock Drawing test, Verbal Fluency test, Digit Span Test and Trail Making test., Results: Results: It has been shown that independently associated with MCI ware age (OR = 1.09, 95% CI: 1.05-1.13) and level of education (OR = 0.75, 95% CI: 0.69-0.81). Depending on the age, it turned out that in the younger MCI group, age, education and depression were significant, and the age and level of education were significant in the older MCI group., Conclusion: Conclusions: The identification of cognitive dysfunctions is an important element of the diagnostic and therapeutic process.

Aim: Children with ultra-short bowel syndrome (USBS) have not been extensively studied to date because the condition is rare. The aim of the study was to assess the nutritional status of children with USBS receiving home parenteral nutrition, using citrulline serum concentration and cholestasis., Methods: We studied 17 patients with USBS, with a median age of 6.6 years and median duration of parenteral nutrition of 6.6 years. The study was carried out at The Children's Memorial Health Institute, Warsaw, from January 2014 to January 2015., Results: The median standard deviation score (SDS) was -1.2 for body mass according to chronological age, -1.72 according to height and -0.59 according to height for age. Patients requiring seven days per week parenteral nutrition had a citrulline concentration below 10 μmol/L. Decreased bone-mineral density was observed in 87% of the patients. Low values of 25-hydroxyvitamin D were found in 53% of the children. None of the patients had elevated conjugated bilirubin levels above 34.2 μmol/L., Conclusion: Children with USBS were growth deficient according to their chronological age, with frequent abnormal bone mineralisation and vitamin D deficiency. Children requiring parenteral nutrition seven days a week had citrulline concentrations below 10 μmol/L. Cholestasis was not seen., (©2018 The Authors. Acta Paediatrica published by John Wiley & Sons Ltd on behalf of Foundation Acta Paediatrica.)

The synthesis and characterization of acyclic and cyclic molecular rotors with 1,4-diethynylphenylene-d 4 rotators are described. The ATR-FTIR and Raman spectra of acyclic rotor 3 and cyclic rotor 5E were measured and interpreted. A feature of ATR-FTIR spectrum of rotor 5E is a strong two-component band around 1730cm -1 attributed to symmetric and asymmetric stretching vibration of the carbonyl group, while this is not observed in rotor 3. Raman investigation in the wide temperature range of 350 - 10K was carried out. The splitting of Raman bands in the region of stretching vibration of CC double and triple bonds at 170 and 260K for rotor 5E is observed. The splitting of bands is due to changes in molecular structure., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Developing the empathic attitude is one of the tasks of medical education as it affects the quality of therapeutic contact in the relationship between the doctor and the participant, conditioning the treatment process. According to Davis's concept, empathy is defined as an affective-cognitive reaction in the context of the other person's experience., Aim: Analysis of profiles of empathic sensitivity in students of medicine. Group: Male and female students of the fifth year of medicine who agreed to participate in an anonymous study (n = 153; M = 57, F = 96; mean age: 23 years). Tools: The Empathetic Sensitivity Scale (EES), which is the Polish tool for Davis's Interpersonal Reactivity Index (IRI) was used. The ESS includes three sub-scales: Empathic Care (EC), Personal Distress (PD) and Adopting Perspective (AP)., Results: The raw results were converted into sten scores and for sten scores for all three dimensions of empathetic sensitivity no differences were found between male and female students. Three clusters (1: n = 33%, 2: n = 39%, 3: n = 28%), which differ in terms of each distinguished indicator, were identified., Conclusions: The first cluster characterizes empathetic people, both in the affective and cognitive spheres, and those dealing well with unpleasant emotions in situations difficult to others. The second cluster characterizes participants with the ability to recognize the needs of others and to take into account their perspectives; the third cluster includes participants with a tendency to focus on own experiences emerging in response to other people's suffering but with the ability to understand a situation and show empathic concern for the other person. The most favourable profile - for a future doctor as well as for his participants - is the first cluster because the doctor, with his empathic sensitivity directed towardsthe other man, can deal with his own unpleasant emotions.

Competing Interests: The authors declare no conflict of interest.

Background: Anticancer therapy entails qualitative and quantitative changes in the physiological bacterial flora of the organism, including the oral microflora., Objectives: The aim of the study was to assess the number of cariogenic bacteria - Streptococcus mutans and Lactobacillus spp. - in the saliva of children with chemotherapy-induced neutropenia, and the relationship between the dynamics of neutrophils in the blood and the number of cariogenic bacteria in the saliva., Material and Methods: The study included 52 children aged 3-17.5 years, diagnosed with cancer and undergoing antineoplastic treatment. The control group comprised 52 generally healthy children matched for age and gender. Both groups underwent microbiological analysis of the saliva. The Dentocult SM Strip Mutans test (Orion Diagnostica, Espoo, Finland) was used to evaluate the number of Streptococcus mutans colonies in the saliva, while the Dentocult LB test (Orion Diagnostica) was used to assess the number of Lactobacillus spp. bacteria. The statistical analysis was carried out using STATISTICA 10 software (StatSoft Inc., Tulsa, USA)., Results: The statistical analysis using Kendall's tau test showed a significant inverse correlation between the number of neutrophils in the blood and the number of the Streptococcus mutans and Lactobacillus spp. colonies in the saliva of the children undergoing anticancer therapy. The highest titres of cariogenic bacteria in the saliva were observed during severe neutropenia, which was frequently observed between day 7 and day 21 of the chemotherapy course., Conclusions: A significant increase in the number of cariogenic bacteria in the saliva during episodes of chemotherapy-induced neutropenia suggests that the activity of dental caries increases in children undergoing antineoplastic treatment.

Background & Aims: Previous studies reported a wide range of estimated malnutrition prevalence (6-30%) in paediatric inpatients based on various anthropometric criteria. We performed anthropometry in hospitalised children and assessed the relationship between malnutrition and length of hospital stay (LOS) and complication rates., Methods: In a prospective multi-centre European study, 2567 patients aged 1 month to 18 years were assessed in 14 centres in 12 countries by standardised anthropometry within the first 24 h after admission. Body mass index (BMI) and height/length <-2 standard deviation scores (SDS, WHO reference) were related to LOS (primary outcome), frequency of gastrointestinal (diarrhoea and vomiting) and infectious complications (antibiotic use), weight change during stay (secondary outcomes) and quality of life., Results: A BMI <-2 SDS was present in 7.0% of the patients at hospital admission (range 4.0-9.3% across countries) with a higher prevalence in infants (10.8%) and toddlers aged 1-2 years (8.3%). A BMI <-2 to ≥-3 SDS (moderate malnutrition) and a BMI <-3 SDS (severe malnutrition) was associated with a 1.3 (CI95: 1.01, 1.55) and 1.6 (CI95: 1.27, 2.10) days longer LOS, respectively (p = 0.04 and p < 0.001). Reduced BMI <-2 SDS was also associated to lower quality of life, and more frequent occurrence of diarrhoea (22% vs 12%, p < 0.001) and vomiting (26% vs 14%, p < 0.001)., Conclusion: Disease associated malnutrition in hospitalised children in Europe is common and is associated with significantly prolonged LOS and increased complications, with possible major cost implications, and reduced quality of life. This study was registered at clinicaltrials.gov as NCT01132742., (Copyright © 2014 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.)

Introduction: Current research from around the world indicates a trend toward younger ages at the first menstruation. At the same time more and more studies point out the negative consequences of early puberty. Early age at menarche is significantly correlated with the risk of metabolic syndrome, breast cancer and female reproductive system cancer, as well as illnesses such asthma and bulimia. The aim of the study was to examine the relationship between age at menarche and socioeconomic status and selected factors connected with biological conditions., Material and Methods: The data were obtained from 671 female university students. Height, weight, waist and hip circumference were measured, and BMI, WHR, WHtR were calculated. A questionnaire form was used to assess the age at menarche, biological conditions and socioeconomic status of the surveyed students., Results: There were no significant differences in the number of the early, average and late maturing students between the socioeconomic groups. The early maturing girls were characterized by higher values of waist circumference, BMI, WHR and WHtR. The prevalence of obesity and abdominal obesity was highest among the early maturing girls. The analysis did not show statistically significant relationships between age at menarche and selected factors connected with biological conditions., Conclusion: Early maturation increases the risk of obesity and central adiposity distribution.

The main purpose of the study was to compare topoisomerase 2α (TOP2A) status in invasive breast carcinomas to the outcome of a therapy containing neoadjuvant treatment with anthracyclines (a combination chemotherapy treatment for breast cancer, namely AC [cyclophosphamide, doxorubicin]). To achieve these goals we created a method of evaluation with criteria based on two methods used in the present study (immunohistochemical [IHC] and fluorescence in situ hybridization [FISH]). The threshold for positive immunohistochemically evaluated status was set for all cases with: nuclear stain intensity score 3+ in 10% or more nuclei and nuclear stain intensity score 2+ in 50% or more nuclei. Our results suggest that TOP2A status may be used as a predictive factor for patient selection for protocols which include anthracyclines as one of the chemotherapeutics. Both methods, IHC and FISH, are suitable for implementation for diagnostic purposes, but IHC positive status measured according to the criteria presented above is the best predictor of longer disease-free survival (DFS) according to our study. Immunohistochemical also gave satisfactory results in all analyzed cases in comparison to only 60% of cases analyzed by FISH.

A series of α-mono- and α,α-difluoro-β-ketophosphonates were synthesized in moderate to good yields with excellent selectivities via electrophilic fluorination by Selectfluor. Subsequently, synthetic potential of the obtained α-monofluoro-β-ketophosphonates was demonstrated by their application in synthesis of α-monofluoro-β-aminophosphonates, useful building blocks in the preparation of phosphapeptides., (© 2011 American Chemical Society)

The effect of exhaustive treadmill exercise on mitochondrial density (MD) and ultrastructural changes in quadriceps femoris muscle was studied in 7 normal, healthy, male mongrel dogs (2-4 years, 15-20 kg) before and after restricted activity (RA) (2 months for 5 dogs, 5 months for 2 dogs), and following a subsequent 2-month exercise retraining period (2-months group). Mean (+/- S.E.) time to exhaustion in the 2-month group decreased from 177 +/- 11 min before to 90 +/- 16 min (delta = -49%, p < 0.05) after RA; retraining increased tolerance to 219 +/- 36 min (delta = +24%, p < 0.05) above the pre-RA and 143% (p < 0.05) above the post-RA time. Post-RA exhaustion time in the 5-months group was 25 and 45 min (35 +/- 10 min). Muscle samples taken after RA showed abnormalities indicative of degeneration, which were reversed by retraining. Resting MD decreased (p < 0.05) from a control level of 27.8% to 14.7% (2 months) and 16.3% (5 months), and was restored to 27.1% (NS) after retraining. Exhaustive exercise caused an increase in MD under control conditions and after RA, but not following retraining. Disruption of mitochondria after exercise was evident after 5-months confinement. Factors causing mitochondrial changes and eventually their disruption during exercise after restricted activity are not related as much to the state of fatigue as to the pre-exercise quality of the muscle modified by disease or training.

Horseradish peroxidase was used to the precise investigation of low molecular protein transport across the kidney barrier. Simultaneously on the parallel material alkaline phosphatase activity was revealed, as this enzyme is connected with the transport processes through cell membranes. The applied reaction diaminebenzidine has shown infiltration spots for low molecular protein at the glomercular barrier and visualized tubular reabsorption of peroxidase in proximal convoluted tubule. Alkaline phosphatase activity has been observed on the surface of podocytes foot processes. On the surface of proximal convoluted tubules brush border and in canals formed with cells basal membranes investigations high activity of alkaline phosphatase was also observed.

Craviten effect on platelets suspended in their own plasma was investigated by two methods of incubation with the drug: the fresh platelets were incubated for 18 h at 4 degrees C with Craviten added to plasma and platelets stored for 18 h at 4 degrees C without Craviten were incubated with Craviten at 37 degrees C for 1 h. For evaluation of the metabolic activity and function of the platelets, the levels of high-energy compounds ATP and ADP, the activity of hexokinase and pyruvate kinase and the amount of adenyl nucleotides released by the platelets after thrombin addition were measured, and the spontaneous aggregation of platelets and c-AMP were determined. The experiments demonstrated that Craviten prevented the fall of ATP level of the stored platelets, raised the activity of hexokinase and pyruvate kinase in the platelets, increased the amount of nucleotides released by the platelets in the release reaction. Craviten inhibited also increased spontaneous aggregation of stored platelets and raised c-AMP level.

The effect of cytostatic drugs used in the treatment of haemopoietic system diseases: cerubidin, hydroxyurea. cytosine arabinoside and their combinations on the platelet count, platelet ultrastructure, metabolic activity and participation in the processes of haemostasis was investigated. The experiments were done using two concentrations of the drugs: clinical corresponding to the maximal single dose and a fivefold as high concentration, It was found that the investigated cytostatic agents and their cominations in the first concentration had no effect of the platelet count, level of free nucleotides, activity of glucose-6-phosphate dehydrogenase and lactic dehydrogenase, and on the reaction of adenine nucleotides release from the platelets induced with thrombin. Using the higher concentration of the drugs it was observed that cerubidin and the combination of cytostatic agents tested changed the shape and ultrastructure of the platelets.

The relationship between the conditions of platelet preservation and their ultrastructure, metabolic activity, and the ability to carry out physiological functions was studied. It was found that storage of platelet concentrates at +4 degrees C for 72 hours reduced the number of platelets, changed their shape decreased the ATP level and the ability of release of adenine nucleotides in response to thrombin. The platelet at +22 degrees C for 72 hours preserved the initial number, normal ultrastructure, intact metabolic activity and the ability of participation in heamostasis processes.

The renal tubules were investigated with the use of ruthenium red and lanthanum nitrate to titrate the carbohydrate groups which are localized on the differentiated surface of the cell membranes and intercellular spaces. Ruthenium red visualized the surface coat which is tightly bound to the outer lamellae of the cell membrane. Lanthanum nitrate used in this investigations is a valuable marker of the intercellular spaces. The applied markers have visualized in the kidney the canals which are originated from the foldings of membranes of the tubular cells which adhere to the basal membrane. The markers used in combination with the fixative glutaraldehyde-paraformaldehyde give an electrondense envelope of the cell membrane which is more distinct as compared with specimen treated with glutaraldehyde and markers only.

Changes in the cellular membrane surface coat of lymphocytes and thymocytes after incubation with cystein in vitro were revealed with electronmicroscope, while performing the reaction with Ruthenium Red and Concanavaline A. Lymphocytes and thymocytes not incubated with cystein to which reaction with Ruthenium red and Cocanavaline A was applied have shown a well developed and preserved surface coat of the cellular membrane. Contrary to this finding when lymphocytes and thymocytes were incubated with cystein and thereafter treated with Ruthenium Red and Concanavaline A no reaction product on the surface of the cellular membrane was observed. The experimental results could indicate on the influence of cystein on the glycoside bonds.