Capturing CO2 by ceria and ceria-zirconia nanomaterials of different origin.

Ceria and ceria-zirconia nanomaterials of different origin were studied in order to elucidate the role of their structural and textural characteristics in controlling the performance towards CO2 capture. Two commercial cerias and two home-prepared samples, CeO2 and CeO2-ZrO2 (75% CeO2) mixed oxide, were investigated. The samples were characterized by a number of analytical techniques including XRD, TEM, N2-adsorption, XPS, H2-TPR, Raman and FTIR spectroscopy. Static and dynamic CO2 adsorption experiments were applied to assess the CO2 capture performance. The type of surface species formed and their thermal stability were evaluated by in situ FTIR spectroscopy and CO2-TPD analysis. The two commercial ceria samples possessed similar structural and textural characteristics, formed the same types of carbonate-like surface species upon CO2 adsorption and, consequently, demonstrated almost identical CO2 capture performance under both static and dynamic conditions. The thermal stability of the adsorbed species increased in the order bidentate (B) carbonates, hydrogen carbonates (HC) and tridentate carbonates (T-III, T-II, T-I). Reduction of CeO2 increased the relative amount of the most strongly bonded T-I tridentate carbonates. Preadsorbed water led to hydroxylation and enhanced formation of hydrogen carbonates. Although the synthesized CeO2 sample had a higher surface area (by 30%) it showed a disadvantageous long mass transfer zone in the CO2-adsorption breakthrough curves. Because of its complex pore structure, this sample probably experiences severe intraparticle CO2 diffusion resistance. Having the same surface area as the synthesized CeO2, the mixed CeO2-ZrO2 oxide exhibited the highest CO2 capture capacity of 136 µmol g-1 under dynamic conditions. This was related to the highest concentration of CO2 adsorption sites (including defects) on this sample. The CeO2-ZrO2 system showed the lowest sensitivity to the presence of water vapor in the gas stream due to the lack of dissociative water adsorption on this material.

Health-related quality of life after ischemic stroke: impact of sociodemographic and clinical factors.

BACKGROUND AND AIMS: Ischemic stroke (IS) is one of the leading causes of death and long-term disability in Bulgaria. IS affects different aspects of the patient's life and results in loss of independence and poor health-related quality of life (HR-QoL). We aimed to analyze the impact of IS on HR-QoL and to identify possible associations with sociodemographic, clinical features, and vascular risk factors (RF). METHODS: A prospective, hospital-based study was undertaken from 1 July 2019 to 31 June 2020, at a tertiary care referral center for neurological disorders in Bulgaria. A total of 150 patients with acute IS - 50 with thrombolytic and 100 with non-thrombolytic therapy - were included. Thorough clinical and sociodemographic data were collected. The NIHSS scale determined stroke severity, and HR-QoL was assessed with the Stroke Impact Scale Version 3.0 (SIS 3.0) during the first 3 months. RESULTS: The overall HR-QoL improved during the observation period, but still, it remained significantly worse. The major predictors of a marked reduction in HR-QoL were age, female sex, lower education level, and actively working at stroke onset, high NIHSS score, anterior circulation stroke, and more extended hospital. Atrial fibrillation and heart failure were significantly associated with poor HR-QoL. The other investigated vascular risk factors were associated with different extends with poorer HR-QoL, except for dyslipidemia. CONCLUSION: Stroke survivors have significantly reduced HR-QoL. Multiple interacting factors are associated with an unfavorable outcome after IS. Early detection of these factors would help to improve the care for IS patients, to reduce disabilities and improve HR-QoL.

Pontocerebellar hypoplasia type 1 for the neuropediatrician: Genotype-phenotype correlations and diagnostic guidelines based on new cases and overview of the literature.

Pontocerebellar hypoplasia type 1 (PCH1) is a major cause of non-5q spinal muscular atrophy (SMA). We screened 128 SMN1-negative SMA patients from Bulgaria for a frequent mutation -p.G31A in EXOSC3, and performed a literature review of all genetically verified PCH1 cases. Homozygous p.G31A/EXOSC3 mutation was identified in 14 Roma patients, representing three fourths of all our SMN1-negative Roma SMA cases. The phenotype of the p.G31A/EXOSC3 homozygotes was compared to the clinical presentation of all reported to date genetically verified PCH1 cases. Signs of antenatal onset of disease present at birth were common in all PCH1 sub-types except in the homozygous p.D132A/EXOSC3 patients. The PCH1sub-types with early death (between ages 1 day and 17 months), seen in patients with p.G31A/EXOSC3 or SLC25A46 mutations have a SMA type 1-like clinical presentation but with global developmental delay, visual and hearing impairment, with or without microcephaly, nystagmus and optic atrophy. Mutations with milder presentation (homozygous p.D132A/EXOSC3 or VRK1) may display additionally signs of upper motor neuron impairment, dystonia or ataxia and die at age between 5 and 18 years. Other EXOSC3 mutations and EXOSC8 cases are intermediate - SMA type 1-like presentation, spasticity (mostly in EXOSC8) and death between 3 months and 5 years. There is no correlation between neurological onset and duration of life. We add marble-like skin and congenital laryngeal stridor as features of PCH1. We show that imaging signs of cerebellar and pontine hypoplasia may be missing early in infancy. EMG signs of anterior horn neuronopathy may be missing in PCH1 patients with SLC25A46 mutations. Thus, there is considerable phenotypic variability in PCH1, with some cases being more SMA-like, than PCH-like. Detailed clinical evaluation and ethnicity background may guide genetic testing and subsequent genetic counseling.

Inherited Thrombophilias Could Influence the Reproductive Outcome in Women with Systemic Lupus Erythematosus.

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease associated with different reproductive complications in the affected women. Inherited thrombophilias are genetic factors increasing the risk for thromboembolism and recurrent pregnancy loss, but their influence on other reproductive disturbances in SLE patients has not been completely clarified. Two hundred and twenty-three Caucasian women (112 with SLE and 111 controls) were included in the study. Complete reproductive history of all SLE patients was carefully obtained. Genotyping for the FVLeiden, FIIG20210A, and MTHFRC677T polymorphisms was performed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis. No significant differences in the prevalence of the FVLeiden, FIIG20210A, and MTHFRC677T polymorphisms between patients and controls were established. Patients with FVLeiden had fewer pregnancies (0.57 ± 0.98 vs. 2.18 ± 1.58; p = 0.007) than the others, while no significant differences in the reproductive history of FIIG20210A carriers and non-carriers were observed (p >0.05). In the SLE group, 41.67% of women with the MTHFRC677T TT genotype had at least one miscarriage in comparison to only 14.00% of the other female patients (p = 0.030). While the prevalence of the investigated thrombophilias was similar in patients with SLE and healthy women, a substantial influence of the inherited prothrombotic factors on the reproductive history of patients was revealed. The investigations of the FVLeiden and MTHFRC677T polymorphisms in SLE patients could help to identify women at highest risk for reproductive failure and thus, further studies in other ethnic groups would be of strong clinical importance.

Melatonin receptor 1b polymorphisms in women with Systemic Lupus Erythematosus.

AIM: The pineal hormone melatonin could exert an important influence on the immune system and autoimmunity. Its effect on the immunocompetent cells might be mediated at least partially through specific melatonin receptors. However, the role of melatonin - melatonin receptor 1B (MTNR1B) interrelations in human autoimmune diseases is still unknown. Therefore, the present study aimed to investigate the possible influence of the MTNR1B gene polymorphisms for the development and clinical expression of systemic lupus erythematosus (SLE). METHODS: 109 female SLE patients and 101 healthy women were genotyped for the MTNR1B rs1562444, rs10830962 and rs10830963 polymorphisms. RESULTS: No genotype distribution differences were found between patients and controls. The presence of MTNR1B rs10830963 C/C genotype was related to increased prevalence of leucopenia compared to genotypes C/G and G/G after Bonferroni correction for multiple comparisons [36.5% vs. 14.5%, p=0.014]. Moreover, the rs10830963 G/G carriers had lower number of lupus criteria in comparison to patients with C/C genotype. CONCLUSIONS: The present data suggested that MTNR1B polymorphisms could influence the clinical features in lupus patients, and especially the susceptibility to leucopenia.

Adsorption of CO2 on MIL-53(Al): FTIR evidence of the formation of dimeric CO2 species.

FTIR spectra of (12)CO2 and (12)CO2 + (13)CO2 mixtures adsorbed on MIL-53(Al) reveal the formation of highly symmetric dimeric (CO2)2 species connected to two structural OH groups.

An advanced approach for measuring acidity of hydroxyls in confined space: a FTIR study of low-temperature CO and (15)N2 adsorption on MOF samples from the MIL-53(Al) series.

Acidity of solids is decisive for their interaction with guest molecules. One of the most used methods for measuring the acidity of surface hydroxyl groups is the hydrogen bond method based on the spectral shift of the OH stretching modes induced by the adsorption of weak bases. However, many materials of practical interest (e.g. metal organic frameworks, zeolites, etc.) are porous and the OH groups are involved in H-bonding with framework basic sites. Here we show that MIL-53(Al) and NH2-MIL-53(Al) samples are characterized by one type of structural hydroxyl but three IR bands are detected at 100 K with these materials (at 3721, 3711 and 3683 cm(-1)). These bands are assigned to structural hydroxyls involved in H-bonding with different strengths. There is no correlation between the acidities of the hydroxyls, as measured by low-temperature CO or (15)N2 adsorption, and the main reason for this is the pre-existing H-bond. A method for the estimation of the intrinsic frequency of the OH groups (i.e. if not participating in H-bonds), based on the analysis of the spectral data obtained with two molecular probes, is proposed. According to this method, the OH stretching frequency of the structural hydroxyls of MIL-53(Al) samples is determined to be 3727 cm(-1). The formation of 1 : 1 adducts between the hydroxyls and strong bases leads to breaking of the pre-existing H-bonds. When the base is weak, bifurcated complexes are formed which slightly affects the spectral shift. The conclusions derived here considerably broaden the applicability of the H-bond method for assessing protonic acidity of materials and systems where the OH groups are preliminarily involved in H-bonding.

[PAL-1 5G/4G polymorphism in patients with systemic lupus erythematosus].

Systemic lupus erythematosus (SLE) is a connective tissue disease affecting predominantly women that has been widely associated with obstetric complications. Inherited thrombophilias are significant risk factors for pregnancy loss, but their role in patients with SLE, and especially in those without concomitant secondary antiphospholipid syndrome (APS) has not been clarified. The aim of the present study was to study PAI-1 5G/4G polymorphism in women with lupus. A total of 103 SLE patients as well as 69 healthy volunteers were genotyped for PAI-1 5G/4G (rs1799889). No significant differences in the PAI-1 5G/4G genotype prevalence between patients and controls were found. After exclusion of the women with secondary APS, the frequency of pregnancies and spontaneous abortions, as well as the number of live births were similar in the studied patients with different PAI-1 genotype (p> 0.05). PAI-1 5G/4G polymorphism was not significantly related to any of the lupus ACR criteria or disease activity (p > 0.05), but it could influence the platelet number in the studied patients (263.52 ± 91.10 [5G/5G genotype] versus 210.12 ± 71.79 [4G/4G genotype], p = 0.023). In conclusion, our results showed that PAI-1 4G/5G polymorphism did not worsen the reproductive outcome in SLE women without secondary APS.

[Ultrasound screening for Down syndrome and other chromosomal abnormalities by fetal nuchal translucency measurement between 11-14 weeks of gestation].

AIM: To assess the feasibility of nuchal translucency [NT] measurement as a screening tool for Down syndrome [DS] and other chromosomal anomalies [ChA] between 11-14 weeks of gestation [w.g.]. MATERIALS AND METHODS: A longitudinal prospective follow up study was carried out at a tertiary referral center including 408 singleton pregnancies between 11+0 and 14+0 w.g. Three experienced sonographers performed transabdominal and/or transvaginal scans using high-resolution ultrasound equipment. The ultrasound examinations included assessment of fetal number and viability, NT measurement and fetal anatomy survey. Down syndrome [DS] risk was calculated using the specialized computer program provided by the Fetal Medicine Foundation [FMF], UK. In cases of estimated DS risk > or = 1:300 invasive prenatal diagnosis was offered--chorionic villus sampling [CVS] between 11-14 w.g. or amniocentesis [AC] after 15 w. g., as well as follow-up scans including fetal echocardiography. The samples were tested by cytogenetic analysis, DNA analysis and/or FISH. When chromosomal fetal abnormality was detected termination of pregnancy was an option. Pregnancy outcome was ascertained from hospital records, referring physicians or the patients themselves. RESULTS: 108 (26%) out of the 408 women were ?35 years and 300 (74%)--below that age. A total number of 9 fetal chromosomal anomalies [ChA] were found including 6 cases with DS, 2--with trisomy 18 [T18] and 1--with Turner syndrome. The overall sensitivity for DS was 66.7% for a false-positive rate [FPR] of 13.4%. The figures for all ChA were 77.7% and 12.8%, respectively. All three cases of ChA other than DS were in the screen-positive group. The overall sensitivity and FPR for ChA for patients > or = 35 years was 80% and 35%, while for patients < 35 years it was 75% and 5.1 %, respectively. Diagnostic invasive procedures were performed in 50 out of 58 screen-positive cases, including 7 of the cases with ChA. In all 7 cases with prenatal diagnosis of fetal ChA the parents chose to terminate the pregnancy. CONCLUSIONS: First trimester DS screening by NT measurement has high sensitivity and specificity. Screening for other chromosomal abnormalities missed by second trimester biochemical serum tests is also possible. Invasive prenatal diagnosis is performed at an early gestational age when termination of affected pregnancies by D&C is still an option. Other important advantages are the possibility of screening for ChA in multiple gestations, as well as early diagnosis of major fetal anomalies.

Separation of enzymes from polyenzyme mixture used in medicine and pharmacy. II. Purification and characterization of extracellular beta-glycosidases with high transglycosylation activities from Aspergillus oryzae.

Three extracellular beta-glycosidases with different substrate specificities have been isolated from Aspergillus oryzae (Luizym) and purified to electrophoretic homogeneity by molecular-sieve and ion-exchange chromatographic methods. The enzymes were characterized as monomeric glycoproteins with an estimated molecular mass of 95 kDa by SDS-PAGE and 92 kDa by gel-permeation chromatography on Superose 12 HR 10/30. beta-glycosidase I (pHopt 4.8; Topt 40 degrees C, pl 4.5) was able to catalyze the hydrolysis of aryl-beta-galactopyranosides (o- and p-), where as gamma-glycosidase II and III were found to be active towards aryl-beta-gluco- and xylopyranosides. The specific chemical modifications of different amino acid residues showed that tryptophyl and carboxyl residues play an important role for the enzyme activity. The isolated beta-glycosidases exhibited high levels of transglycosylation activities and were used for the production of tri- and tetrasaccharides from lactose and whey permeate.

Y-chromosomal STR haplotypes in three major population groups in Bulgaria.

A total of 280 unrelated males from the three largest population groups in Bulgaria: Bulgarians, Bulgarian Turks and Gypsies, were analyzed for seven Y-chromosome STRs (DYS19, DYS389I, DYS389II, DYS390, DYS391, DYS392 and DYS393). Comparison of the allele frequency distributions revealed significant differences between the three ethnic groups which were confirmed with haplotype analysis. This permits us to suggest that population differentiation should be taken into account in forensic case analysis and paternity testing in Bulgaria.

Psychopathology and psychosocial causes in adult deliberate self-poisoning in Plovdiv region, Bulgaria.

INTRODUCTION: The percentage of deliberate self-poisoning among acute intoxications continues to be high in the medical practice worldwide; in Plovdiv region it reaches 64% of all acute poisoning cases. MATERIAL AND METHODS: A representative retrospective study of 311 acute deliberate self-poisoning cases over 14 years of age, treated in the Regional toxicological center of Plovdiv region between 01.01.1990 and 31.12.1998 was carried out. The following factors were studied: gender, age, type of poisoning, psychiatric diagnosis and psychosocial stressors. The classification criteria of Diagnostic and Statistical Manual--4th edition (DSM-IV) of the American Psychiatric Association were applied. RESULTS: We identified a first attempt of deliberate self-poisoning in 237 patients (71.6%) and a second consecutive attempt in 62 patients (18.7%). Thirty two (9.7%) of the attempts were committed in a state of alcohol intoxication. The percentage of women was statistically significantly higher. The age group of 14-19 years represented the highest percentage (27%). In 168 patients (50.8%) a psychiatric disorder was diagnosed. Adjustment disorder (53.57%) and depressive and schizophrenic disorders (26.79%) were the leading diagnoses among adults committing deliberate self-poisoning. The problems with primary support group (in 61.8% as a single stressor and in 13.71% in combination with other stressors) were the most common psychosocial factors for deliberate self-poisoning. CONCLUSIONS: To reduce the number of adult deliberate self-poisonings, measures including harmonization of the relationships in the primary support group and active treatment of patients with depressive and schizophrenic disorders are needed.

Our experience in the treatment of acute Amanita phalloides poisoning.

INTRODUCTION: The present study aimed at investigating phalloid mushroom poisoning and the toxicological aid services in Plovdiv region as this pathology shows in this country high mortality rate (40-100%) and increasing incidence; it is difficult to diagnose and is far from featuring adequately in the literature in our country. MATERIAL AND METHODS: A caseload of 270 patients with mushroom poisoning from Plovdiv region, Bulgaria, admitted for treatment to the Clinic of Toxicology, Higher Medical Institute, Plovdiv, for the period 1991-1998 was studied. Of these 270 patients 25 (9.26%) had an acute phalloid poisoning. The following indicators were registered: gender, age, reported type of consumed mushrooms, time of appearance of the first complaints after the mushroom consumption, time of medical aid, disease outcome. The diagnosis and the applied treatment was based on our own diagnostic-therapeutic protocol for phalloid intoxication. RESULTS: All phalloid poisoning cases were accidental by character. The most frequently reported type of ingested mushroom was unidentified wild edible mushrooms. Of all the patients males were 56%, females--44% with mean age of 47.71 years (SD = 17.53). From 25 phalloid poisoning cases 15 survived (60%), 10 died (40%). The summer-fall seasonal pattern of phalloid poisoning occurrence was apparent. The mean duration of the latency period was 12 hours (SD--6.66). In 4 (16%) patients the disease exhibited an unusually early onset--up to 2 hours after the mushroom ingestion. The mean time period from the mushroom ingestion to the presentation in a medical institution for first medical aid was 32 hours (SD--21.69), for men--27.59 hours, for women--43.75 hours. Almost one third (32%) of the diseased presented for medical help more than 36 hours after the poisoning. CONCLUSIONS: The acute mushroom poisoning cases in adults comprise 7.01% of the total acute poisoning caseload. The phalloid poisoning accounts for 9.26% of the total number of patients with mushroom poisoning admitted for treatment. The application of contemporary diagnostic-therapeutic protocol lowers the hospital lethality rate from phalloid poisoning to 40%. There were no statistically significant differences in the compared parameters between the subgroups of patients with favorable and lethal outcome and between the subgroups of men and women--most probably due to the small sample. In order to lower the incidence and mortality rate from phalloid mushroom poisoning the authors recommend preventive health education on the problem, targeting the population at risk and the introduction of contemporary diagnostic and treatment methods--determining the amatoxins, intravenous application of Silibinin and liver transplantation.

Aspects of granulocyte function in workers professionally exposed to pesticides.

Granulocyte function in 92 workers from a chemical plant for the production of pesticides was tested by means of the nitro-blue tetrazolium test (spontaneous and stimulated) and the phagocytosis test. Two opposite types of change were identified, namely increased and reduced functional activity. No reliable correlation between the studied parameters and length of service was found. In comparison with the routine hematological methods, the identified functional changes in polymorphonuclear neutrophil granulocytes serve as an early indicator of an impact on the leukocytes. The applied methods are accessible and may be used as an objective means of studying the dynamics of the unfavorable effect of zineb and of identifying groups at increased toxicological risk.

[Endoscopic assessment of hemorrhage from the gastrointestinal tract]. / Endoskopska otsenka na kruveneto ot gastro-intestinalniia trakt.

The causes of gastrointestinal bleedings was assessed by fiber gastroscopy, rectoromanoscopy and fiber colonoscopy. The most frequent causes of bleedings from the upper gastrointestinal tract are gastric and duodenal ulcers, erosive hemorrhagic gastritis, gastric cancer, liver cirrhosis with bleeding from varicose veins, polyps, diverticuli, Mallory-Weiss syndrome, etc. The most frequent causes of bleedings from the lower gastrointestinal tract are hemorrhoids, anal fissures, colonic polyps, chronic ulcerohemorrhagic colitis, rectal carcinoma, etc. The diagnostic importance of urgent endoscopic examinations is pointed out.