Gas permeation properties of three highly permeable perfluorinated polymers (polyhexafluoropropylene (PHFP), amorphous Teflon AF2400, and polyperfluoro(2-methyl-2-ethyl-dioxole-1,3) (PPFMED)), which ...are promising materials for the dense thin layer of hollow fiber membranes for extracorporeal membrane oxygenation have been studied using nitrogen, oxygen, and carbon dioxide. Hemocompatibility of the polymeric films has also been investigated on whole blood from healthy donors. Gas permeation of the polymers increases in the order PHFP < PPFMEDD < AF2400, with PHFP alone having the permeability coefficients of the gases do not below those of polydimethylsiloxane applied as the selective layer of blood oxygenation membranes. Hemocompatibility of the polymers declines in the order PHFP > PPFMED > AF2400, with the most permeable polymer AF2400 exhibiting the worst hemocompatibility among the other polymers studied. Polyperfluoro(2-methyl-2-ethyl-dioxole-1,3) is shown to be the most appropriate polymer to fabricate hollow fiber membranes for blood oxygenation.
Aim
. To study the gender and age characteristics of dyslipidemia in the population of the Nizhny Novgorod region.
Material and methods
. A total of 2501 people aged 35-74 among the population of the ...Nizhny Novgorod region were examined, selected by stratified multi-stage random sampling. The study was performed as part of the third epidemiological study ESSE-RF3. All respondents underwent an anthropometric survey, a questionnaire to identify chronic non-communicable diseases and related risk factors. The following laboratory tests were performed: total cholesterol (TC), low-density lipoproteins (LDL-C), high-density lipoproteins (HDL-C), triglycerides (TG). Among the entire cohort of patients at the time of blood sampling, 276 people (11,0%) were receiving lipid-lowering drugs. They were excluded from further analysis. Hypercholesterolemia (HCL) was recorded with a total cholesterol ≥5,0 mmol/l, an increased level of LDL-C — with a level ≥3,0 mmol/l, hypertriglyceridemia (HTG) — with a TG ≥1,7 mmol/l, a reduced level of HDL-C — with a level in males ≤1,0 mmol/l, in women ≤1,2 mmol/l.
Results
. The prevalence of HCL was 65,1%. In the young cohort (40-44 years), men were significantly more likely to have hypercholesterolemia, but in the middle (50-54 years) and older (60 years or more) age groups, this lipid metabolism disorder was observed with greater frequency among females. In addition, 68,9% of the respondents had elevated LDL-C levels. When studying the prevalence of this type of dyslipidemia in different age groups among men and women, a similar trend can be noted with similar TC values, but significant gender differences in the prevalence of elevated LDL-C levels l were revealed only in the 60-64 and 65-69 years groups. The prevalence of HTG among the adult population of the Nizhny Novgorod region was 42,6%. Among the 35-49 years and 55-59 years age groups, the prevalence of elevated TG levels was significantly more common among men. The incidence of decreased HDL-C levels was 13,3%. This type of dyslipidemia was significantly more often detected among men only in the youngest subgroup (35-39 years).
Conclusion
. Among the population of the Nizhny Novgorod region, hypercholesterolemia occurred in 65,1% of respondents, an increased level of LDL-C — in 68,9%, a HTG — in 42,6%, a reduced level of HDL-C — in 13,3%. The data obtained determine a high cardiovascular risk and require the development of prevention and treatment measures for lipid metabolism disorders.
Purpose
: to evaluate the effectiveness of platelet-rich plasma lysate (PRP) in the treatment of patients with post-traumatic eyelid scarring by clinical examples.
Material and methods
. Patients ...with post-traumatic scarring changes in eyelid tissues causing a damage in the functional and cosmetic state of the auxiliary apparatus of the eye were treated in the Department of Plastic Surgery and Eye Prosthetics at the Helmholtz National Medical Research Center of Eye Diseases. Two of the patients, who had been traumatized shortly before the examination and one patient who had rejected surgery were offered treatment by PRP lysate manufactured at the Sklifosovsky Medical Research Institute of Emergency Medicine. After local infiltration anesthesia, each patient received a single injection of PRP lysate (2 ml) into the scar tissue. The result was evaluated at a follow-up that took place 3 months after the injection.
Results
. The clinical picture of the three patients showed a pronounced positive dynamic of the functional and cosmetic state of the auxiliary eye apparatus, which made the patients reject subsequent (additional) surgical treatment.
Conclusion
. An improvement tissue repair and regeneration processes after PRP lysate injection allows us to assess this method as an applicable alternative of reconstructive operations in certain cases.
Aim . To evaluate the usage of antihypertensive drugs (AHDs) and their combinations in participants aged 35 to74 years with arterial hypertension (AH) in the population-based study ESSE-RF3. Material ...and methods . Representative samples of the population aged 35 to 74 years from 15 regions of Russia (n=28731) with a response rate over 70% were examined in the ESSE-RF3 study. Therapy received by 9944 participants with AH (with systolic BP ≥140 mm Hg and/or diastolic BP ≥90 mm Hg, or when the subject was taking AHDs) was analyzed. Information about AHDs intake (brand name of the drug) was recorded by questionnaire and coded according to International Nonproprietary Names by classes. Statistical analysis was performed using the open-source R 4.1 environment. Comparison of discrete indicators between groups was performed using Fisher’s exact test. The significance level for all tested hypotheses was taken as.05. The study was approved by the Ethics Committee of FGBI “NMRC TPM” of the Ministry of Health of the Russian Federation, each participant signed an informed consent. Results . Among the patients receiving therapy for AH, angiotensin-converting enzyme inhibitors (ACEIs) were used by 38.8% of participants, angiotensin receptor blockers (ARBs) — 31.6%, betablockers (BBs) — 29.0%, сalcium channel blockers (CCBs) — 21.5%, diuretics — 18.6%, 1.1% — outdated AHDs; 8.6% — other groups of drugs. Monotherapy was used by 53.1% of patients, 33.1% of participants received two, and 13.9% received three AHDs. Among participants taking two or more AHDs (including single-pill combinations (SPC)), males most often received the combination of BB+ ACEI and females — BB+ARBs. SPC AHDs were used by 10.3% of those receiving therapy (males: 9.8%, females: 10.6%). Among SPCs, the top three combinations were CCBs + ACEIs (28%), diuretics + ACEIs (27.5%), and diuretics + ARBs (24.4%). Conclusion . The population study ESSE-RF3, based on the survey of a representative sample of the Russian population aged 35-74 years, showed that more than a half of participants with AH receiving therapy were used the monotherapy, only every tenth of those treated received SPC. The problem of insufficient patients’ literacy was indicated — about 1% of patients received outdated AGPs. In addition, 8.6% of patients used non-AHDs for the treatment of AH. For improving the control of AH treatment, it is necessary to increase the adherence of patients to the prescribed therapy and more strict adherence of doctors to the published guidelines for AH treatment.
Precision Etching of Thin Doped Silicon Layers Borovkova, A. Yu; Grischina, T. N.; Matyuhina, E. S.
Journal of communications technology & electronics,
03/2018, Letnik:
63, Številka:
3
Journal Article
Recenzirano
The optimum etchant composition for precise removal of a thin high-doped silicon gettering layer is determined. It is found that the best-controlled etching is provided by the following composition: ...HNO
3
: HF: CH
3
COOH = 40: 1: 1. This composition etches the entire gettering layer away while preserving the required thickness of the contact layer, which prevents the space-charge region of the
p–n
junction from emerging at the back surface of the base of a photosensitive element. Thus, this etchant provides an opportunity to reduce the magnitude of dark currents and raise the percentage yield.
Purpose
: to study the effectiveness of the use of thrombofibrin clot of platelet-rich plasma (PRP) in patients with corneal ulcers.
Material and methods
. A clinical study, conducted by the ...Department of Traumatology and Reconstructive Surgery of Helmholtz National Medical Research Center of Eye Diseases, involved 20 patients, aged from 22 to 82, with corneal ulcers of inflammatory and burn genesis more than 100 microns deep. All patients got coated with a thrombofibrin PRP clot from autologous blood. Prior to the study, all patients received standard treatment for 2 weeks to 3 months, including multiple amniotic membrane coating, with no effect. The thrombofibrin clot was produced by the Scientific Department of Biotechnology and Transfusiology of the N.V. Sklifosovsky Research Institute for Emergency Medicine. The ready clot was placed on the surface of the cornea and covered with an amniotic membrane. The membrane was fixed to the episclera along the border of the limb with a circular suture, whereupon autologous serum was injected along the limb in 4 quadrants, to be followed by temporary lateral blepharography.
Results
. On the 2nd day following the procedure, the patients noted a decrease in lacrimation and pain in the operated eye. As shown by optical coherence tomography, the average depth of the corneal ulcer at the beginning of the study in all patients was 129 ± 28.5 microns. On the 5
th
day, the depth lowered to an average of 71 ± 32.6 microns, and on the 10
th
day, to 23.3 ± 15.1 microns. In 7 patients (35%), complete healing of the defect was observed on the 15
th
day, while in 9 patients (45%) it was stated between the 16
th
and the 20
th
day. Thus, the average time of healing of the ulcer with complete epithelization occurred was 15 days. In four patients with the consequences of severe burns (20%), the ulcer did not heal due to extensive damage to the limbal zone.
Conclusion
. The use of a thrombofibrin PRP clot in combination with amniotic membrane transplantation allows achieving a stable and fairly rapid healing of corneal ulcers of various origins. However, this method is ineffective in patients with limbal cell insufficiency, severe burns and extensive damage to the limbal zone. In such cases, it is advisable to use more radical surgical methods, such as buccal or limbal cell transplantation, or allolimbal transplantation.
Purpose:
to evaluate the effectiveness of anti-scar treatment of eyelid tissues with platelet-rich plasma (PRP) lysate by pathomorphological examination.
Material and methods.
20 patients (men aged ...27–64 years with eyelid scars caused by traumatic tissue rupture) underwent reconstructive plastic surgery on their eyelids. All patients had similar injuries and traumatic agents, the type and localization of the scar, and the same duration of the post-traumatic period (12 months after the injury). The patients were divided into 2 groups depending on the application of anti-scar treatment using PRP lysate in the preoperative period. The treatment consisted in injecting a personalized biotransplant into the scar tissue. During the surgery, a fragment of scar tissue was taken from each patient for pathomorphological examination.
Results.
In the control group, the pathomorphological picture was of the same type and corresponded to the third phase of wound healing with remodeling and the formation of a rough scar. The third phase of wound healing with scar remodeling in patients of the main group was characterized by significantly less pronounced fibrotic-dystrophic changes in both cellular and stromal components of the dermis and hypodermis.
Conclusion.
In the main group with PRP lysate therapy, scar tissue was characterized by significantly less pronounced fibrotic-dystrophic changes in both cellular and stromal components of the dermis and hypodermis as compared to the control group. The observed morphological picture was close to a complete involution of the scar with its restructuring, approaching the normal histoarchitectonics of the dermis and hypodermis.
Purpose: to evaluate the effectiveness of platelet-rich plasma (PRP) lysate in patients with corneal erosion or posttraumatic scarring of eyelid tissues.Material and methods. The study involved 30 ...patients aged 22 to 82 (51.5 ± 19.1 years): 10 with persistent corneal erosions, who were treated in 2 stages (2 weeks of standard keratoprotective therapy, then treatment supplemented with instillations of PRP lysate) and 20 patients with post-traumatic scarring of eyelid tissues, who were divided into a clinical group and a comparison group. PRP lysate was produced in the cell transplantation and immunotyping laboratory of N.V. Sklifosovsky Research Institute for Emergency Medicine.Results. In group 1, already on the 3rd day of PRP lysate use, a positive dynamic of the cornea was observed: all patients had fewer complaints of pain, photophobia, and lacrimation. Corneal biomicroscopy, performed daily over the entire epithelization period, revealed a decrease in hyperemia of the tarsal and bulbar conjunctiva and corneal edema, which indicated a weakened inflammatory response. On average, the area of the cornea at the start of traditional therapy was 21.6 19.6; 30.65 mm2. After two weeks of treatment, at the time of adding PRP lysate, the average area of erosion fell to 15.7 12; 18.9 mm2, after a week of treatment with lysate, it dropped to an average of 2.35 0.4; 4.3 mm2. On day 14, all patients revealed complete epithelialization of the corneal defect. In patients with post-traumatic eyelid tissue scars, after a 3-month-long use of PRP lysate (study group), an improvement was noted in the cosmetic and functional state of the eyelids, on average by 4 points (Me = 12 10; 12 points before and 8.5 8; 9 points after treatment (on the Manchester scar assessment scale), in contrast to the patients who received no anti-scar therapy (comparison group), as the latter showed a deterioration in the condition of eyelid scars by 1–2 points (Me = 11 10.25; 11.75 points at the beginning and 12 11; 12 points at the end of the observation period). The acoustic density of scar tissue in the study group approached the normal values, in contrast to the comparison group, in which scar tissue appeared to be hypoechoic.Conclusion. Using PRP lysate aimed at improving the repair and regeneration processes in patients with corneal erosion or post-traumatic scarring of eyelid tissues is promising and requires further clinical study.
Structural and functional properties of the human tendon tissue complicate process of tendon-based grafts preserving. In the process of preservation, it is necessary to maintain mechanical and ...functional parameters of the tendon tissue as well as to provide sterility and biological safety of the graft. One could conclude effectiveness of techniques, combining tendon conservation at low temperatures and sterilization with the supercritical carbon dioxide.
Aim of work
: to find optimal conditions for allogeneic tendon grafts sterilization with supercritical carbon dioxide.
Materials and methods
. Allogeneic tendons were prepared from the tissue donors, following the rules of asepsis and antisepsis. After quarantine and confirmation of the absence of blood-borne infections the tendon grafts were divided into 3 groups: in the control group the tendons were not subjected to cryopreservation and sterilization procedures; in 2 experimental groups tendons were treated with a cryoprotector 10 % dimethyl sulfoxide (DMSO) solution and sterilized with supercritical carbon dioxide with slow gas discharge (group 2) or with fast gas discharge (group 3); the duration of sterilization in both groups varied from 1 to 12 hours. The toxicity of the grafts was assessed in human mesenchymal multipotent stromal cells (MMSC) culture on the 3rd and 7th days. The sterility of the grafts was confirmed on the 7th and 14th day by bacteriological culture on thioglycol medium and Saburo broth. Mechanical tests were performed on testing machine LLOYD Instruments LR5K Plus with the tensile speed 5 mm/min.
Results.
Histological analysis showed, that in the group with slow gas discharge collagen fibers retained their integrity and topography and contained only local minor tears; in all terms of treatment, the tendon grafts were sterile and nontoxic. On the contrary, in the group with fast gas discharge there was marked damage of the collagen fibers and growth of bacterial and fungal flora was observed in the culture. The grafts of the control group and the group, where sterilization with supercritical carbon dioxide was performed with slow gas discharge for 1-12 hours, were used to evaluate mechanical characteristics. In the preserved tendons the stiffness and ultimate strain did not significantly differ from the similar values in the control (p > 0.05), on the contrary, the level of ultimate strain in all experimental specimens was significantly reduced by 1.5-2.1 times comparing to the control. Young's modulus and load at rupture in the control grafts and grafts, sterilized for 1 hour, had similar values, whereas in grafts, sterilized from 3 to 12 hours, these parameters were 1.4-2.1 times lower (p < 0.05).
Conclusions.
The suggested technique of tendon preservation, using cryoprotector DMSO and sterilization with the supercritical carbon dioxide, allows to obtain sterile and non-toxic grafts. The structure of cells and fibers of the preserved tendons did not significantly disturbed. For supercritical carbon dioxide sterilization of tendon grafts the most optimal processing time is 1 hour.
The purpose
. Using clinical observation, to study the feasibility of applying a coagulant and to assess its efficacy in the treatment of patients with post-burn erosion of the cornea.
Material and ...methods
. The treatment was carried out in the Department of Trauma and Reconstructive Surgery, the Helmholtz Moscow Research Institute of Eye Diseases, Russia. Based on clinical test results, the patient, was diagnosed with post-burn persistent erosion of the cornea with sub-total cornea conjunctivization and: limbal stem cell deficiency (LSCD) in the right eye. The keratoprotective therapy conducted for several months turned ineffective. In order to activate the cornea regeneration process, the erosion site was covered with autologous thrombofibrin clot that had been obtained from the stabilized blood. Following a two-stage centrifugation of patient's stabilized blood, the plasma with the platelets were collected into a round-bottomed test-tube; and the chloride calcium activator was added. The clot was formed in the thermostat at a temperature of 37 С. The patient was given a local anesthesia, and the thrombofibrin clot was placed on the cornea surface and covered with an amniotic membrane. The membrane was fixed with a circular stitch along the limbus of the cornea.
Result
. The patient was followed-up and showed positive changes over time in the form of a diminished erosion area at day 5 and a complete corneal epithelialization at day 14.
Summary
. Our methodaimed at enhancing the reparative and regenerative processes in the cornea, reducing swelling, accelerating epithelialization, expanding transparency, and improving the optic characteristics thanks to less intensive opacity formation showed a high efficacy.
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