The Impact of Rationing Nursing Care on Patient Safety: A Systematic Review.

BACKGROUND Rationing of nursing care (RONC) has been associated with poor patient outcomes and is a growing concern in healthcare. The aim of this systematic study was to investigate the connection between patient safety and the RONC. MATERIAL AND METHODS A thorough search of electronic databases was done to find research that examined the relationship between restricting nurse services and patient safety. The systematic review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Two reviewers (M.L. and A.P.) independently screened the titles and abstracts, and full-text articles were assessed for eligibility. Data were extracted, and a quality assessment was performed using appropriate techniques. RESULTS A total of 15 studies met the inclusion criteria. The studies included in the review demonstrated a correlation between rationing of nursing care and patient safety. The results of these studies revealed that there is an inverse relationship between rationing of nursing care and patient safety. The review found that when nursing care is rationed, there is a higher incidence of falls, medication errors, pressure ulcers, infections, and readmissions. In addition, the review identified that the work characteristics of nurses, such as workload, staffing levels, and experience, were associated with RONC. CONCLUSIONS RONC has a negative impact on patient safety outcomes. It is essential for healthcare organizations to implement effective strategies to prevent the RONC. Improving staffing levels, workload management, and communication amo0ng healthcare providers are some of the strategies that can support this.

Quality of Life and Pain in Patients With Chronic Pancreatitis.

INTRODUCTION: The quality of life (QoL) of patients with chronic conditions is a function of factors associated with the illness, its natural course, and treatment as well as those related to the patient. Chronic pancreatitis (CP) is a critical public health problem. Chronic pancreatitis patients can experience chronic pain with different mechanisms, malabsorption, diabetes, and cachexia. OBJECTIVE: Chronic pancreatitis (CP) is a critical public health problem. CP patients can experience chronic pain with different mechanisms, malabsorption, diabetes, and cachexia. The aim of the study was to assess the Quality of Life (QoL) of patients with CP and identify factors affecting QoL. METHODS: 104 patients diagnosed with CP from the hospital in Wroclaw, Poland, were included. The study was conducted using our own questionnaire, the World Health Organization Quality of Life-BREF (WHOQOL-BREF) scale, the 36-Item Short Form Health Survey (SF-36), and the Visual Analog Scale (VAS). RESULTS: The mean total SF-36 score was 47.7, with the highest mean rating for the physical functioning domain. The mean VAS pain score was 5.13. Pain intensity was significantly correlated with impairments in activities of daily living (P = 0.001), the need to reduce their duration (P = 0.001), and the performance of physical activity (P = 0.003). Comorbidities, education, and age have a significant relationship with only some domains of SF-36. CONCLUSIONS: One aspect that has an impact on QoL impairment is pain which perception is governed by the same brain regions in which abnormalities result in depression and anxiety. QoL in CP patients also depends on the patient's age, comorbidities, and level of education.

Covalent segmented polymer networks composed of poly(2-isopropenyl-2-oxazoline) and selected aliphatic polyesters: designing biocompatible amphiphilic materials containing degradable blocks.

To promote facile and efficient synthesis of segmented covalent networks, we developed a cross-linking process with reactive polymeric components in a system without catalysts or side products. To achieve the direct formation of amphiphilic networks, an addition reaction was performed between the polyesters containing carboxyl terminal groups with pendant groups distributed along poly(2-isopropenyl-2-oxazoline) chains. Covalent cross-linking was achieved from predetermined amounts of components dissolved in DMSO at 140 °C. To tune the properties of the resulting networks, the composition and length of the polyester segments and the degree of cross-linking were changed in the feed. The chemical structure of the networks was characterized using Fourier transform infrared-attenuated total reflection spectroscopy and 13C magic-angle spinning NMR. The swelling ability of the formed networks was investigated in aqueous and organic media. Moreover, mechanical properties were tested during uniaxial compression. The cytocompatibility of the scaffolds was confirmed by MTT assay. Through the results obtained, the first report describing the cross-linking of polyesters on hydrophilic PiPOx was provided to prepare new, biocompatible materials with tuneable properties that are promising for potential biomedical applications.

Influence of the AlSi7Mg0.6 Aluminium Alloy Powder Reuse on the Quality and Mechanical Properties of LPBF Samples.

Additive manufacturing (AM) is dynamically developing and finding applications in different industries. The quality of input material is a part of the process and of the final product quality. That is why understanding the influence of powder reuse on the properties of bulk specimens is crucial for ensuring the repeatable AM process chain. The presented study investigated the possibility of continuous reuse of AlSi7Mg0.6 powder in the laser powder bed fusion process (LPBF). To date, there is no study of AlSi7Mg0.6 powder reuse in the LPBF process to be found in the literature. This study aims to respond to this gap. The five batches of AlSi7Mg0.6 powder and five bulk LPBF samples series were characterised using different techniques. The following characteristics of powders were analysed: the powder size distribution (PSD), the morphology (scanning electron microscopy-SEM), the flowability (rotating drum analysis), and laser light absorption (spectrophotometry). Bulk samples were characterised for microstructure (SEM), chemical composition (X-ray fluorescence spectrometry-XRF), porosity (computed tomography-CT) and mechanical properties (tensile, hardness). The powder was reused in subsequent processes without adding (recycling/rejuvenation) virgin powder (collective ageing powder reuse strategy). All tested powders (powders P0-P4) and bulk samples (series S0-S3) show repeatable properties, with changes observed within error limits. Samples manufactured within the fifth reuse cycle (series S4) showed some mean value changes of measured characteristics indicating initial degradation. However, these changes also mostly fit within error limits. Therefore, the collective ageing powder reuse strategy is considered to give repeatable LPBF process results and is recommended for the AlSi7Mg0.6 alloy within at least five consecutive LPBF processes.

Adverse childhood experiences and low socioeconomic status with respect to allostatic load in adulthood: A systematic review.

Early-life psychosocial stress primes a number of health risk behaviors, and contributes to the development of various mental and somatic disorders in adulthood. It has been reported that adverse childhood experiences (ACEs) and low socioeconomic status (SES) might be associated with allostatic load (AL) in adulthood. In turn, elevated AL index has been found to predict a number of unfavorable health outcomes. Therefore, we aimed to perform a systematic review of studies investigating the association of ACEs and childhood SES with AL in adult populations. Independent online searches covered the publication period up to 20th Jun 2021. A total of 27 studies were included in qualitative synthesis. The majority of eligible studies showed that ACEs (14 out of 19 studies recording ACEs, 73.7%) and low childhood SES (11 out of 12 studies recording childhood SES, 91.7%) are associated with elevated AL in adults. However, several processes were found to mediate or moderate this association. These include educational attainments, social support, health behaviors, adult stress, post-traumatic stress disorder, coping strategies and aging. Moreover, a substantial methodological heterogeneity of approaches to calculating the AL index was observed. Apart from reports from overlapping samples, none of eligible studies used the same set of biomarkers. Findings from this systematic review imply that early-life psychosocial stress might have a lasting impact on biological dysregulations captured by the AL index. Future studies need to explore whether the association between early-life stress and the AL index accounts for the development of specific health outcomes.

A simple strategy for efficient preparation of networks based on poly(2-isopropenyl-2-oxazoline), poly(ethylene oxide), and selected biologically active compounds: Novel hydrogels with antibacterial properties.

Novel polymer networks composed of biocompatible, hydrophilic poly(2-isopropenyl-2-oxazoline) (PiPOx), poly(ethylene oxide) (PEO), and selected biologically active compounds (cinnamic acid, benzoic acid or eugenol) were developed for potential antimicrobial applications. The applied crosslinking method, based on the addition reaction between oxazoline pendant groups and chosen reagents containing carboxyl functions, is relatively facile, free from by-products, and thus well suited for biomaterial preparation. The one-step synthesis enabled efficient network formation with high gel contents (>90%). The chemical structure of the newly synthesized networks was characterized using Fourier Transform Infrared-attenuated Total Reflection spectroscopy (FTIR-ATR) and 13C Magic-Angle Spinning (MAS) NMR. To evaluate the suitability for biomedical applications, swelling in water and the mechanical properties of the networks were investigated. The antimicrobial efficacy of the prepared hydrogels was tested in neutral medium both by the agar diffusion method and in the liquid culture against Gram-positive and Gram-negative strains: Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae and Enterobacter cloaceae. All the tested hydrogels showed an antimicrobial effect in the direct contact zone. Moreover, the eugenol loaded hydrogel expressed a broader bacteriostatic effect inhibiting microorganism growth beyond the contact zone. These form-stable hydrogels with antibacterial properties may be of interest for designing materials dedicated to biomedical applications.

Biological evaluation of selective laser melted magnesium alloy powder.

PURPOSE: The current study examined magnesium alloy AZ31B specimens manufactured with Additive Manufacturing method (selective laser melting - SLM) to investigate the applicability of this technology for the production of medical devices. METHODS: Osteoblast cells and bacterial biofilm growth ability on specimen was examined and the effect of surface state on corrosion resistance was evaluated by electrochemical and immersion methods. RESULTS: High survival of hFOB cells, as well as a strong tendency for Pseudomonas aeruginosa and Staphylococcus aureus biofilm proliferation on the surface of the tested specimens were shown. SLM-processed AZ31B alloy has a higher corrosion resistance in 0.9% NaCl solution and in a multi-electrolyte saline solution than the material in a conventional form of a rolled sheet. CONCLUSIONS: It has been demonstrated that the strong development of the surface of as-built processed specimens results in a significantly increased corrosion rate, which hinders the production of complex structures in tissue engineering products that support cell ingrowth.

The Co-Culture of Staphylococcal Biofilm and Fibroblast Cell Line: The Correlation of Biological Phenomena with Metabolic NMR1 Footprint.

Staphylococcus aureus is one of the most prevalent pathogens associated with several types of biofilm-based infections, including infections of chronic wounds. Mature staphylococcal biofilm is extremely hard to eradicate from a wound and displays a high tendency to induce recurring infections. Therefore, in the present study, we aimed to investigate in vitro the interaction between S. aureus biofilm and fibroblast cells searching for metabolites that could be considered as potential biomarkers of critical colonization and infection. Utilizing advanced microscopy and microbiological methods to examine biofilm formation and the staphylococcal infection process, we were able to distinguish 4 phases of biofilm development. The analysis of staphylococcal biofilm influence on the viability of fibroblasts allowed us to pinpoint the moment of critical colonization-12 h post contamination. Based on the obtained model we performed a metabolomics analysis by 1H NMR spectroscopy to provide new insights into the pathophysiology of infection. We identified a set of metabolites related to the switch to anaerobic metabolism that was characteristic for staphylococcal biofilm co-cultured with fibroblast cells. The data presented in this study may be thus considered a noteworthy but preliminary step in the direction of developing a new, NMR-based tool for rapid diagnosing of infection in a chronic wound.

Morphology and Plastic Yielding of Ultrahigh Molecular Weight Polyethylene.

The structure, morphology, and mechanical properties of two compression-molded grades of ultrahigh-molecular-weight polyethylene (UHMWPE) and, for comparison, one conventional linear polyethylene (HDPE) were studied. Compression molding resulted in some preferred orientation of lamellae in the compression direction in UHMWPE samples, while no preferred orientation in HDPE. The mean crystal thickness estimated from the size distribution agrees better with those obtained from small-angle X-ray scattering (SAXS) and mechanical yield data than the thickness determined from the melting peak temperature. Microscopic examination of microtomed and etched UHMWPE samples showed that the lamellae are in the form of platelets with the width and length in the range of 300-700 nm. The lamellae radiate from primary nuclei forming small embryonal spherulites; their radial growth ends at 0.3-0.7 µm from the center. There is no evidence of branching and secondary nucleation from those primary lamellae. Because the lamellae are radially ordered, there is no parallel stacking of lamellae. Samples were subjected to deformation by plane-strain compression at a constant true strain rate. In axial UHMWPE samples, where lamellae were preferentially oriented along the loading direction, the second yield was clearly observed. The second yield was found to be related to the deformation instability leading to kinking of lamellae oriented initially along the loading direction. Kinking was clearly shown by SAXS and microscopic observation of microtomed and etched samples. No cooperativity of kinking was observed because the lamellae are arranged in small spherulites and not parallel in stacks. The stress-strain curves were fitted with model curves assuming crystal plasticity and network elasticity in the amorphous component. The effective density of the molecular network within the amorphous phase depended on the molecular weight of UHMWPE.

Is hyperhomocysteinemia a causal factor for heart failure? The impact of the functional variants of MTHFR and PON1 on ischemic and non-ischemic etiology.

BACKGROUND: Hyperhomocysteinemia was found to be uniformly associated with the development of heart failure (HF) and HF mortality; however, it is uncertain whether this relation is causative or not. We used Mendelian randomization to examine the associations of the methylene tetrahydrofolate gene (MTHFR) and paraoxonase 1 gene (PON1) variants as a proxy for lifelong exposure to high Hcy and Hcy-thiolactone concentrations with the development of HF in men aged ≤60years and the occurrence of adverse effects at one-year follow-up. METHODS: The study enrolled 172 men with HF: 117 with ischemic etiology (iHF) related to coronary artery disease (CAD) and 55 with non-ischemic etiology (niHF) related to dilated cardiomyopathy (DCM). The reference group of 329 CAD patients without HF and the control group of 384 men were also analyzed. RESULTS: Hyperhomocysteinemia (OR=2.0, P<0.05) and the MTHFR 677TT/1298AA, 677CC/1298CC genotypes (OR=1.6, P=0.03) were associated with HF regardless of its etiology, especially among normotensives (OR=4.6, P=0.001 and OR=2.3, P=0.003, respectively). In niHF, the PON1 162AA (OR=2.3, P=0.03) and 575AG+GG (OR=0.46, P=0.01) genotypes also influenced the risk. The interaction between HDLC<1mmol/L and the PON1 575GG genotype was found to influence the risk of iHF (OR=7.2, P=0.009). Hyperhomocysteinemia improved the classification of niHF patients as 'high-risk' by 10.1%. Ejection fraction <30% and DCM increased the probability of HF death or re-hospitalization within one year. CONCLUSION: Our results provide evidence that hyperhomocysteinemia is a causal factor for niHF in DCM, while dysfunctional HDL could contribute to the pathogenesis of iHF.

The chemical digestion of Ti6Al7Nb scaffolds produced by Selective Laser Melting reduces significantly ability of Pseudomonas aeruginosa to form biofilm.

In our previous work we reported the impact of hydrofluoric and nitric acid used for chemical polishing of Ti-6Al-7Nb scaffolds on decrease of the number of Staphylococcus aureus biofilm forming cells. Herein, we tested impact of the aforementioned substances on biofilm of Gram-negative microorganism, Pseudomonas aeruginosa, dangerous pathogen responsible for plethora of implant-related infections. The Ti-6Al-7Nb scaffolds were manufactured using Selective Laser Melting method. Scaffolds were subjected to chemical polishing using a mixture of nitric acid and fluoride or left intact (control group). Pseudomonal biofilm was allowed to form on scaffolds for 24 hours and was removed by mechanical vortex shaking. The number of pseudomonal cells was estimated by means of quantitative culture and Scanning Electron Microscopy. The presence of nitric acid and fluoride on scaffold surfaces was assessed by means of IR and rentgen spetorscopy. Quantitative data were analysed using the Mann-Whitney test (P ≤ 0.05). Our results indicate that application of chemical polishing correlates with significant drop of biofilm-forming pseudomonal cells on the manufactured Ti-6Al-7Nb scaffolds ( p = 0.0133, Mann-Whitney test) compared to the number of biofilm-forming cells on non-polished scaffolds. As X-ray photoelectron spectroscopy revealed the presence of fluoride and nitrogen on the surface of scaffold, we speculate that drop of biofilm forming cells may be caused by biofilm-supressing activity of these two elements.

Cavitation during tensile deformation of isothermally crystallized polypropylene and high-density polyethylene.

The cavitation phenomenon was studied in isothermally and non-isothermally crystallized polypropylene and high-density polyethylene. It was found that nano-voids were not present in the crystallized samples, but were formed during their tensile deformation. The process of cavitation was initiated before reaching the yield point. The ellipsoidal voids were initially elongated perpendicularly to the deformation direction, but if the polymer (i.e., high-density polyethylene) was able to deform beyond the yield, then the reorientation of voids into the deformation direction was observed at local strains of 100-200 %. This behavior was similar to that observed previously in the samples crystallized without an exact control of solidification conditions. The calculations of Guinier's radius showed that voids in deformed polypropylene samples were characterized by the gyration radii of 28-50 nm. Smaller voids were observed in polyethylene. The scale of cavitation during deformation, studied on the example of polyethylene, depended on the preceding crystallization process and was most intensive for the specimens crystallized at the highest temperature of 125 °C.

Parathyroid adenoma diagnosed on the basis of a giant cell tumor of parieto-occipital region and multifocal bone injuries.

Brown tumors are rare skeletal manifestations of hyperparathyroidism (HPT) that may mimic cancer metastases. Histopathologically, they are difficult to differentiate from other giant cell lesions. A case is presented of 41-year-old woman with giant cell tumor in parieto-occipital region with injury of external bone lamina, growing into the skull cavity. The mass was suspected of being neoplastic. Numerous osteolytic lesions in the skull skeleton and multifocal bone injuries were observed, also. Elevation in calcium (5.91 mEq/L) and parathormone (1188 ng/mL) concentrations and hypercalciuria (52 mEq/24 h) suggested the diagnosis of HPT initially manifesting as a brown tumor of the skull. Further exploration confirmed the existence of parathyroid adenoma as a cause of the disease. The key treatment for the condition was surgical excision of the adenoma followed by the normalization of parathyroid function and significant reduction in size of skull tumor and other lesions.

[Smoking enhances the decrease of adiponectin level in patients with coronary artery disease, carriers of MTHFR 677T and PON1 55M alleles]. / Palenie tytoniu nasila obnizenie poziomu adiponektyny u osób z miazdzyca tetnic wiencowych, nosicieli alleli MTHFR 677T i PON1 55M.

Decreased adiponectin level, the adipose tissues hormone, is related to high body mass and insulin resistance, which are risk factors for atherosclerosis. It was shown, that cigarette smoking and high homocysteine (Hcy) level are associated with low level of adiponectin. In the presented study we search for the associations between 5 polymorphisms in genes involved in Hcy metabolism - methylenetetrahydrofolate reductase (MTHFR) and paraoxonase 1 (PON1), smoking, adiponectin levels and insulin resistance in subjects with coronary artery disease (CAD). The studied group consisted of 152 patients subjected to coronary arteriography. In 116 patients significant atherosclerotic changes in vascular vessels were confirmed (CAD group), remaining patients were considered as the control group. In studied group, the levels of glucose, insulin, adiponectin and blood lipids profile were measured. Adiponectin and insulin levels were determined by radioimmunological assays. The insulin resistance was calculated using mathematical HOMA model. MTHFR 677C>T, 1298A>C, PON1 -108C>T, L55M, Q192R polymorphisms were ascertained by PCR-RFLP methods. In the studied group (N = 152), significantly decreased adiponectin levels and higher degree of insulin resistance were present in subjects with angina pectoris (N = 129) and peripheral atherosclerosis (N = 32), whereas in the cases of CAD, confirmed in coronary arteriography (N = 116), only the higher degree of insulin resistance was noted. Arterial hypertension (p = 0.004), diabetes mellitus (p = 0.03) and smoking (p = 0.04) were the most significant vascular risk factors associated with the low adiponectin levels. In CAD group, negative correlations between the level of adiponectin and the dose of MTHFR 677T (r = - 0.238; p < 0.05) and PON1 55M (r = -0.251; p < 0.05 alleles were found. The MTHFR 677T allele was also correlated with degree of insulin resistance (r = 0.391; p < 0.05). In smokers, these genetic associations were stronger (r = -0.394; = -0.353; r = 0.440; respectively), which demonstrates, that the negative effects of MTHFR 677T and PON1 55M alleles are enhanced by smoking. Moreover, only in smokers the correlations between adiponectin levels and: the degree of insulin resistance (r = -0.465; p < 0.01) and the levels of HDLC (r = 0.479; p < 0.01) were seen. In summary, in CAD patients, particularly in smokers, occurrence of MTHFR and PON1 risk alleles is associated with the decreased adiponectin levels and/or increased degree of insulin resistance.

Exit-site care in Austrian peritoneal dialysis centers -- a nationwide survey.

BACKGROUND: Catheter-associated infections markedly contribute to treatment failure in peritoneal dialysis (PD) patients. There is much controversy surrounding prophylactic strategies to prevent these infections. METHODS: In this nationwide multicenter study we analyzed strategies to prevent catheter-associated infections as performed in Austrian PD centers in 2006. A questionnaire was sent to all 23 PD centers in Austria. RESULTS: Ten different catheter models were used in the 332 patients being treated in the 23 Austrian PD centers. Systemic antibiotics prior to catheter placement were given by 17 of the 23 PD centers (glycopeptides, n = 7; cephalosporins, n = 10). Nasal swabs were taken preoperatively by 17 PD centers; nasal Staphylococcus aureus carriers were treated prophylactically with mupirocin cream in 15 of these centers. Dressing change was routinely performed in 318 of 332 chronic PD patients (nonocclusive film dressing, n = 58; gauze dressing, n = 260). Disinfectants for chronic exit-site care included povidone iodine (n = 155), sodium hypochlorite (n = 31), povidone iodine + sodium hypochlorite together (n = 102), and octenidine dihydrochloride/phenoxyethanol (n = 17). Water + non-disinfectant soap or 0.9% sodium chloride was administered as a cleansing agent to the exit site by 27 patients. Routine S. aureus screening (nasal and/or exit-site swabs) in chronic PD patients was performed in 12 PD centers; carriers were treated with mupirocin cream in 11 of these centers. Dialysis staff members were screened for S. aureus in 8 PD centers and spouses were screened for S. aureus in 5 PD centers. The overall exit-site infection rate was 1 episode/43.9 patient-months, tunnel infection rate was 1 episode/88.9 patient-months, and peritonitis rate was 1 episode/51.0 patient-months. Patients of centers that have installed a prophylaxis protocol for treating S. aureus carriers had lower mean infection rates compared with those not using such a protocol. CONCLUSION: Various individual prophylactic strategies are used to prevent catheter-associated infections in Austrian PD centers. Infection rates are within the range reported in the literature. There is still scope for improvement in some centers (e.g., by establishing a prophylaxis protocol).

Reflector luminaire with high power light-emitting diodes for general lighting.

The lighting parameters of LEDs are constantly improving. They should not however be applied directly in general lighting luminaires. Luminous intensity distribution solid of high power LEDs is inappropriate for the uniform lighting of a target surface and produces too high of a luminance for this luminaire for large elevation angles. We analyzed the luminous intensity curves allowing us to achieve the best possible lighting uniformity and limited distribution of the luminous flux. Specially manufactured reflectors with limited height were applied in the designed luminaire model. The application of 30 white and additionally six red diodes in the same luminaire provided the resulting optical radiation with the color temperature of 3702 K and a color rendering index of 81.

[In patients with coronary artery disease and left ventricular contractile insufficiency the pathogenicity of smoking associates with imbalance in metabolism of homocysteine]. / U chorych z miazdzyca tetnic wiencowych i niewydolnoscia skurczowa lewej komory, szkodliwosc palenia wiaze sie z zaburzeniami metabolizmu homocysteiny.

Development of the systolic left ventricular insufficiency in patients with coronary artery disease (CAD) markedly decreases the survival rates, so the factors affecting the clinical status of these patients should be reevaluated. The left ventricular contractile function has been assessed by measurements of the left ventricular ejection fraction (LVEF) values. The studied group of 160 males comprised 102 CAD patients diagnosed by coronarography, and 58 persons without CAD and left ventricular systolic insufficiency. The CAD patients were divided into 2 subgroups according to the LVEF values: 53 patients qualified to have normal left ventricular contractile function (with LVEF > 40%), and 49-patients, with LVEF < or = 40%, were considered as subgroup with the left ventricular contractile insufficiency. In the case-control set up the effects of smoking, concentrations of homocysteine (Hcy) and folic acid (FA) and of the known risk factors of the vascular diseases in the development of the left ventricular contractile insufficiency were assessed. Moreover, analysis was performed of the association between LV insufficiency and the statin therapy and the number of infarcts. LV insufficiency in CAD patients associated with increased diastolic pressure (p = 0.006) and with increased uric acid concentrations in plasma (p = 0.02). The smoking, decrease in HDL-C and increased index TC/HDLC were the risk factors of CAD, independent of the LV insufficiency. In comparison to the CAD patients with the preserved systolic function, in the group of CAD patients with LV systolic insufficiency, more persons had recurrent infarcts (34.7% vs. 5.7%), and less persons had no infarct (8.2% vs. 20.8%, p < 0.05). In CAD patients with LV systolic insufficiency smoking associated with the higher values of HC/FA index (p = 0.01), younger age of the patients (p = 0.01), the number of persons not treated with statins (0.01) and the number of persons not having had heart infarct before (p < 0.05). These findings confirm both the effects of infarcts on the development of LV insufficiency, and the presumed association between the pathogenicity of smoking in LV insufficiency and the unbalanced metabolism of Hcy. The straight of the effect of smoking on the development of LV insufficiency in susceptible persons is shown also by the findings of the younger age of the smoking CAD patients as compared to the nonsmoking patients with LV insufficiency.

[The different genotypes of MTHFR 1298A>C and PON1 -108C>T polymorphisms confer the increased risk of the abdominal aortic aneurysm in the smoking and nonsmoking persons]. / Rózne genotypy polimorfizmów MTHFR 1298a>C i PON1 -108c>T sa czynnikami ryzyka wystapienia tetniaka aorty brzusznej u osób palacych i niepalacych.

In abdominal aortic aneurysm (AAA) both the etiology and the pathogenesis are of the multifactorial character. The genetic component in the determination of this disease is proven by its familial occurrence. Smoking represents the best recognized risk factor of the AAA development. Increased concentrations of homocysteine (Hcy) in plasma are the common finding in these patients. It is assumed that the Hcy thiolactone, the most reactive metabolite of Hcy, may participate in the aortic wall destruction in AAA. The polymorphic variants of the methylenetetrahydrofolate reductase (MTHFR 677C>T and 1298A>C) influence tissue concentrations of the Hcy. Paraoxonase (PON1), the enzyme associated in plasma with the HDL fraction, as lactonase detoxicates the Hcy thiolactone. The promotor polymorphism of PON1 - 108C>T gene may determine the lower activity of this enzyme. In the case-control study of 106 patients with AAA and 97 healthy persons, the effects of selected genetic and nongenetic risk factors on development of AAA were assessed, considering the possibilities of interaction between them. It was found, that the arterial hypertension, cigarette smoking and the lower HDL fraction are independent risk factors of AAA. The arterial hypertension was a risk factor both in the smoking and the nonsmoking males, whereas the lower HDL fraction has been the risk factor only for the smoking men. By the multivariate analysis in the nonsmoking males the MTHFR 1298 AC and CC genotypes increased the risk of AAA development 4,8-fold in relation to the MTHFR 1298 AA nonsmoking males. In reference to the genotypes of the expected high impact on the metabolism of Hcy and of Hcy thiolactone, the genotypes of MTHFR 677TT and PON1 -108CT and TT were more frequent in smoking ones, but the difference was not significant. This observation fits with the assumption that the influence of smoking on the occurrence of AAA prevails over that of genetic variability. When the patients age was considered in the analysis, the PON1 -108CT and TT genotypes were identified as the significant risk factors for the development of AAA in the older smokers.

[The normotensive carriers of the MTHFR 677T allele, displaying the increased risk of development of the abdominal aortic aneurysm (AAA), occur at the highest frequency among the smoking patients]. / Nosiciele allela MTHFR 677T, zwiekszajacego ryzyko wystapienia tetniaka aorty brzusznej (AAA) u osób z prawidlowym cisnieniem tetniczym, wystepuja najczesciej w grupie chorych palacych.

Abdominal aortic aneurysm (AAA) presents itself as a progressive dilation of the abdominal aorta, leading--if untreated--to rupture. It is a common disease of the elderly, with a complex etiology. Smoking, hypertension and several genetic factors are recognized as relevant for the pathogenesis of AAA. We studied association between the polymorphism of the MTHFR (methylenetetrahydrofolate reductase) gene within the fourth exon (677C>T) and the occurrence of hypertension and smoking status in the group of 74 male patients with AAA. In the patients group, the smoking hypertensive persons represented the largest subgroup (43%). We determined the the MTHFR 677C>T polymorphism in AAA patients and compared it to that in 71 healthy normotensive males. The frequencies of the 677T allele and MTHFR 677C>T genotypes were similar in both groups, but the subgroup of normotensive AAA patients (n=29) displayed significantly increased frequencies of 677T allele (0.4) and of 677CT and TT genotypes (69%), as compared to those in the control group (0.28 and 46%, respectively). This corresponds to the 3.3-fold greater risk of AAA in normotensive subjects with the 677T allele of MTHFR, as compared to the homo-zygotes 677CC (p<0.03; 95% CI=1.2-9.2). The highest frequencies of MTHFR 677T allele (0.43) and 677CT and TT genotypes (73%) were found in the subgroup of normotensive smoking patients (n=22).

Increased risk of the abdominal aortic aneurysm in carriers of the MTHFR 677T allele.

Abdominal aortic aneurysm (AAA) presents itself as a progressive dilation of the abdominal aorta, leading--if untreated--to rupture. It is a common disease of the elderly, with a complex etiology. Several genetic, biochemical and environmental factors are recognized as relevant for the pathogenesis of AAA. We determined the polymorphism of the MTHFR (methylenetetrahydrofolate reductase) gene within the fourth exon (C677T) in 63 patients with AAA and compared it to that in 75 subjects of the population sample. The frequencies of the C/C, C/T and T/T genotypes were 65%, 27%, and 8% in the population sample and 33%, 60%, and 6% in the patients. This corresponds to a 4.4-fold greater risk of AAA in subjects who have the 677C/T variant of MTHFR, as compared with those who are 677C/C (p < 0.0001; 95% CI=2.11-9.34). The frequency of allele MTHFR 677T in patients (0.37) was higher than in the population sample (0.21; p < 0.007). This association between the common allele of the MTHFR gene--MTHFR 677T--and the development of AAA suggests that elevated homocysteine (Hcy) may disturb the function of the aortic wall. The disturbance may involve enhancement of elastin degradation, the process enhanced by mild hyperhomocysteinemia in minipigs. The magnitude of this effect, which refers to the AAA patients unselected for familial occurrence, indicates that the disturbance of aortic wall physiology caused by the presence of the MTHFR 677T allele is greater than the effect of the earlier described allele disequilibrium at the polymorphic alleles of the PAI1 (plasminogen activator inhibitor 1) gene seen only in familial cases of AAA.