231 research outputs found

    Economical Alternatives for High Sensitivity in Atomic Spectrometry Laboratory

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    The most commonly used analytical tools for determination of elements at trace levels are atomic absorption spectrometry (AAS), inductively coupled plasma, optical emission and mass spectrometry (ICP-OES and ICP-MS) and atomic fluorescence spectrometry (AFS). Although sensitive plasma techniques are becoming predominant in most of the western laboratories, AAS keeps its importance in developing countries. Simple and inexpensive ways of enhancing sensitivity will be described for laboratories equipped with only a flame AA spectrometer. Although there are many chemical preconcentration procedures to improve sensitivity of flame AAS, only some atom trapping techniques will be included here. One kind of atom trapping device is a slotted quartz tube (SQT) used for in situ preconcentration of analyte species followed by a rapid revolatilization cycle to obtain an enhanced signal. These devices provide limits of detection at a level of µg L-1. Another kind of atom trapping involves use of vapor generation technique and quartz or tungsten atom trapping surfaces. The analytical steps consist of the generation of volatile species, usually by hydride formation using NaBH4, trapping these species at the surface of an atom trap held at an optimized temperature and finally re-volatilizing analyte species by rapid heating of trap. These species are transported using a carrier gas to an externally heated quartz tube as commonly used in hydride generation AAS systems; a transient signal is formed and measured. These traps have limits of detection in the order of ng L-1

    Evaluation of Ovarian Histomorphology and Function Following Clomiphene Citrate and Human Chorionic Gonadotropin Administration in Wistar Rats

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    Polycystic ovarian syndrome (PCOS), affecting 5-10% of women, is a leading cause of infertility affecting 10-15% of couples globally. Human chorionic gonadotropin (hCG) and clomiphene citrate (CC) are often utilized for the treatment of PCOS. Accordingly, this study explored the effects of CC and hCG on ovarian histomorphology and fertility parameters. Twenty adult female rats were divided into four groups as follows: Group A (control) received only feed and water; Group B received 0.7 mg/kg BW of CC twice daily for five days and was mated before sacrifice on day 19 (before litter); Group C received 0.7 mg/kg BW of CC twice daily for five days, followed by mating and allowed to litter before sacrifice; Group D received 0.7 mg/kg body weight (BW) of hCG on day one, followed by 0.7 mg/kg BW of CC twice daily for five days, and were mated before sacrifice on day 7 (before litter). Results showed that Group B rats had higher, more than other groups, Follicle-stimulating hormone (FSH), Estradiol, Testosterone and Prolactin levels when compared to the control. Similarly, rats in Group B had higher levels of Progesterone while Group D had higher levels of Luteinizing hormone (LH) when compared to the control group. Histological findings demonstrated diverse impacts on ovarian structures, ranging from congested blood vessels to haemorrhages and follicular cysts. Consequently, this study underscores the complexities of drug interactions in reproductive health and provides preliminary insights into the possible adverse effects of CC and hCG on the ovary and fertility parameters

    Mitochondria as a Target of Environmental Toxicants

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    Enormous strides have recently been made in our understanding of the biology and pathobiology of mitochondria. Many diseases have been identified as caused by mitochondrial dysfunction, and many pharmaceuticals have been identified as previously unrecognized mitochondrial toxicants. A much smaller but growing literature indicates that mitochondria are also targeted by environmental pollutants. We briefly review the importance of mitochondrial function and maintenance for health based on the genetics of mitochondrial diseases and the toxicities resulting from pharmaceutical exposure. We then discuss how the principles of mitochondrial vulnerability illustrated by those fields might apply to environmental contaminants, with particular attention to factors that may modulate vulnerability including genetic differences, epigenetic interactions, tissue characteristics, and developmental stage. Finally, we review the literature related to environmental mitochondrial toxicants, with a particular focus on those toxicants that target mitochondrial DNA. We conclude that the fields of environmental toxicology and environmental health should focus more strongly on mitochondri

    Clinical features of patients with posterior wall myocardial infarction, complicated by the right ventricule injury

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    According to the literature the frequency of expansion of posterior wall myocardial infarction (MI) to the right ventricle reaches 25%. At the same, the relevance of timely diagnosis of this clinical condition is due to the complexity of its implementation and the fact that treatment of right ventricle MI has a number of significant features (significantly limiting the indications of nitropreparates, ACE inhibitors and other vasodilatators, particularly relevant reperfusion therapy and efforts to reduce complications). The object of our research was to study clinical and functional characteristics of patients with posterior wall MI complicated by the right ventricle injury. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/675

    Association study between BGLAP RS1800247-polymorphic variant and type 2 diabetes mellitus development among hypertensive and non-hypertensive Ukrainians

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    The risk of type 2 diabetes mellitus (T2DM) development depends on a hereditary predisposition. According to the current data, bone tissue enhances insulin gene expression in pancreatic β-cells as well as increases insulin sensitivity of adipocytes, myocytes and hepatocytes through the secretion of undercarboxylated osteocalcin (unOCN). The aim. To analyze the relation between rs1800247 SNP and T2DM occurrence depending on the arterial hypertension (AH) presence, as well as association between rs1800247 and systolic, diastolic, pulse, mean blood pressure among patients with T2DM. Materials and methods. This study included 153 patients with diagnosed T2DM and 311 individuals without any carbohydrate metabolism disorders. Polymerase chain reaction-restriction fragment length polymorphism analysis (PCR-RFLP) was used for BGLAP rs1800247-genotyping. Logistic regression with interaction term “genotype × AH” was used to estimate the association between BGLAP rs1800247-genotypes and T2DM development in dominant, recessive, over-dominant and additive models of inheritance. Linear regression was performed to examine the influence of minor C-allele on the arterial blood pressure. Lipid profile characteristics of T2DM patients were stratified by rs1800247-genotype using ANOVA with Bonferroni post hoc test. All calculations were performed using Statistical Package for the Social Sciences software (SPSS, version 22.0, Chicago, IL, USA). A value of P ˂ 0.05 was considered as significant. Results. No association was found between rs1800247 single nucleotide polymorphism and T2DM development neither in AH patients, nor in subjects without AH (Paint b > 0.05). There was no impact of rs1800247 genotypes on systolic, diastolic, pulse and mean blood pressure among patients with T2DM (P > 0.05). It was showed that T2DM non-hypertensive CC-carriers had significantly lower levels of total cholesterol (P = 0.012) and LDL cholesterol (P = 0.04), but higher concentration of HDL cholesterol (P = 0.015) compared to the TT-genotype. Conclusions. It was showed that CC-carriers had more favorable parameters of lipid metabolism among T2DM non-hypertensive Ukrainians. However, there was no association between rs1800247 SNP and T2DM development as well as blood pressure parameters

    Thr83ala Gene Polymorphism Association with Arterial Calcification, Acute Coronary Syndrome and Ischemic Strokes in Older Adults

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    BACKGROUND: Calcification of the arteries of the lower extremities is a very common pathological process, which has an independent significance in the development of cardiovascular diseases. There is evidence that development of calcification of the arteries correlates with a mutation of the MGP protein gene representing by the Thr83Ala polymorphism.AIM: The purpose of the study was to analyse the connection of Thr83Ala polymorphism of the MGP gene with the development of calcification of the arteries of the lower extremities.METHODS: The study involved 80 patients. Half of them had signs of calcification of the arteries of the lower extremities. The allelic Thr83Ala polymorphism of the MGP protein gene was determined by polymerase chain reaction, establishing the presence of calcification of the arteries by radiological and dopplerographic methods.RESULTS: The study aimed to analyse the association of the Thr83Ala polymorphism of the matrix Gla protein gene with the development of calcification of the arteries of the lower extremities. The data obtained suggest that the replacement of threonine by alanine in the 83rd position of the MGP molecule can affect the functional properties of the protein and in particular its anticarcinogenic properties. Although there was no difference in the distribution of different variants of the genotype by Thr83Ala to the MGP gene polymorphism in patients with CA and healthy patients, but in the distribution of genotypes in the comparison groups separated by sex, it was found that in women, carriage of the Ala allele in a homozygous state is a factor, which protects the development of arterial calcination in the elderly and senile.CONCLUSION: Differences in the distribution of different variants of the genotype according to Thr83Ala to the polymorphism of the MGP gene between patients with CAD and healthy patients do not exceed the limits of statistical significance. In the distribution of genotypes in the comparison groups divided by sex, it was found that in women the carrier of the Ala-allele in the homozygous state is a factor that prevents the development of Menkeberg arteriosclerosis in the elderly and old age

    Retrospective matched-pairs analysis of bortezomib plus dexamethasone versus bortezomib monotherapy in relapsed multiple myeloma

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    Bortezomib-dexamethasone is widely used for relapsed myeloma in routine clinical practice, but comparative data versus single-agent bortezomib are lacking. This retrospective analysis compared second-line treatment with bortezomib- dexamethasone and bortezomib using 109 propensity score-matched pairs of patients treated in three clinical trials: MMY-2045, APEX, and DOXIL-MMY-3001. Propensity scores were estimated using logistic regression analyses incorporating 13 clinical variables related to drug exposure or clinical outcome. Patients received intravenous bortezomib 1.3 mg/m2 on days 1, 4, 8, and 11, in 21-day cycles, alone or with oral dexamethasone 20 mg on the days of/after bortezomib dosing. Median bortezomib cumulative dose (27.02 and 28.60 mg/m2) and treatment duration (19.6 and 17.6 weeks) were similar with bortezomib-dexamethasone and bortezomib, respectively. The overall response rate was higher (75% vs. 41%; odds ratio=3.467; P<0.001), and median time-to-progression (13.6 vs. 7.0 months; hazard ratio [HR]=0.394; P=0.003) and progression-free survival (11.9 vs. 6.4 months; HR=0.595; P=0.051) were longer with bortezomib-dexamethasone versus bortezomib, respectively. Rates of anygrade adverse events, most common grade 3 or higher adverse events, and discontinuations due to adverse events appeared similar between the groups. Two patients per group died of treatment-related adverse events. These data indicate the potential benefit of bortezomib-dexamethasone compared with single-agent bortezomib at first relapse in myeloma. The MMY-2045, APEX, and DOXIL-MMY-3001 clinical trials were registered at, respectively, clinicaltrials.gov identifier: 00908232, 00048230, and 00103506

    Surface-Initiated Controlled Radical Polymerization: State-of-the-Art, Opportunities, and Challenges in Surface and Interface Engineering with Polymer Brushes

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    The generation of polymer brushes by surface-initiated controlled radical polymerization (SI-CRP) techniques has become a powerful approach to tailor the chemical and physical properties of interfaces and has given rise to great advances in surface and interface engineering. Polymer brushes are defined as thin polymer films in which the individual polymer chains are tethered by one chain end to a solid interface. Significant advances have been made over the past years in the field of polymer brushes. This includes novel developments in SI-CRP, as well as the emergence of novel applications such as catalysis, electronics, nanomaterial synthesis and biosensing. Additionally, polymer brushes prepared via SI-CRP have been utilized to modify the surface of novel substrates such as natural fibers, polymer nanofibers, mesoporous materials, graphene, viruses and protein nanoparticles. The last years have also seen exciting advances in the chemical and physical characterization of polymer brushes, as well as an ever increasing set of computational and simulation tools that allow understanding and predictions of these surface grafted polymer architectures. The aim of this contribution is to provide a comprehensive review that critically assesses recent advances in the field and highlights the opportunities and challenges for future work

    Factors affecting study efficiency and item non-response in health surveys in developing countries: the Jamaica national healthy lifestyle survey

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    BACKGROUND: Health surveys provide important information on the burden and secular trends of risk factors and disease. Several factors including survey and item non-response can affect data quality. There are few reports on efficiency, validity and the impact of item non-response, from developing countries. This report examines factors associated with item non-response and study efficiency in a national health survey in a developing Caribbean island. METHODS: A national sample of participants aged 15–74 years was selected in a multi-stage sampling design accounting for 4 health regions and 14 parishes using enumeration districts as primary sampling units. Means and proportions of the variables of interest were compared between various categories. Non-response was defined as failure to provide an analyzable response. Linear and logistic regression models accounting for sample design and post-stratification weighting were used to identify independent correlates of recruitment efficiency and item non-response. RESULTS: We recruited 2012 15–74 year-olds (66.2% females) at a response rate of 87.6% with significant variation between regions (80.9% to 97.6%; p < 0.0001). Females outnumbered males in all parishes. The majority of subjects were recruited in a single visit, 39.1% required multiple visits varying significantly by region (27.0% to 49.8% [p < 0.0001]). Average interview time was 44.3 minutes with no variation between health regions, urban-rural residence, educational level, gender and SES; but increased significantly with older age category from 42.9 minutes in the youngest to 46.0 minutes in the oldest age category. Between 15.8% and 26.8% of persons did not provide responses for the number of sexual partners in the last year. Women and urban residents provided less data than their counterparts. Highest item non-response related to income at 30% with no gender difference but independently related to educational level, employment status, age group and health region. Characteristics of non-responders vary with types of questions. CONCLUSION: Informative health surveys are possible in developing countries. While survey response rates may be satisfactory, item non-response was high in respect of income and sexual practice. In contrast to developed countries, non-response to questions on income is higher and has different correlates. These findings can inform future surveys
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