Synthesis, characterization and biological evaluation of zinc(ii) complexes with phenanthroline derivatives and s-methyl dithiocarbazate schiff bases

Dissertação de mestrado, Inovação Química e Regulamentação (Erasmus Mundus), Faculdade de Ciências e Tecnologia, Universidade do Algarve, 2017The discovery of novel active compounds with new mechanisms of action, higher efficacy and improved selectivity is a matter of urgency to multi drug resistance and toxicity problems associated with many therapeutic drugs. In the current work S-methyl dithiocarbazate Schiff base: SalSmdt, Mp(Smdt)2, VanSmdt, PySmdt and their Zn(II) complexes: Zn[(SalSmdt)(H2O)]0.5H2O, Zn2[(Mp(Smdt)2)(CH3COO)], Zn[(VanSmdt)(H2O)] and Zn[(PySmdt)(CH3COO)]1.5H2O were synthesized. The Schiff bases were obtained by condensation of S-methyl dithiocarbazate (smdt) with different aromatic aldehydes: salicylaldehyde (sal), o-vanillin (van), pyridoxal (py) and 2,6-diformyl-4-methylphenol (Mp). Additionally, Zn[(phen)2(NO3)2]2H2O, Zn[(aminophen)2(NO3)2]1.5H2O and Zn[(Mephen)2(NO3)2]3.5H2O complexes were developed by reaction of Zn(II) with 1,10- phenanthroline (phen), 4,7-dimethyl-1,10-phenanthroline (Mephen) and 5-amino-1,10- phenanthroline (aminophen). All compounds were characterized by elemental analysis, FTIR, UV-Vis, NMR, MS and fluorescence spectroscopies. The characterization suggests that the Schiff base ligands coordinate the metal ion through the phenolate–O, the imine-N and the sulfur atom in the thiol form (except in Zn[(PySmdt)(CH3COO)] for which the thione is proposed). The stability of the compounds in buffered aqueous media (5 % DMSO and 95 % PBS, pH 7.4) was evaluated and all compounds are stable at least for three hours. The antioxidant potential was tested using the 2,2-diphenyl-1-picrylhydrazyl assay. All S-methyl dithiocarbazate Schiff bases showed moderate antioxidant activity but the Zn(II) complexes, with the exception of Zn[(PySmdt)(CH3COO)], are inactive. The Zn-phenanthroline complexes were tested for their DNA binding ability by fluorescence spectroscopy. The results indicate that there is interaction between the complexes and calf thymus DNA. Cytotoxicity studies with several tumor cell lines (PC-3, MCF-7 and CACO-2) are ongoing. The results obtained for the Schiff bases are promising since the IC50 values ranged from 4.41 to 28.99 μM. The phenanthroline ligands and their corresponding Zn complexes showed very high cytotoxicity towards A2780 ovarian cancer cells, with the Zn complexes showing slightly higher activity than the ligands.A descoberta de novos fármacos, com mecanismos de acção alternativos, maior eficácia e selectividade é urgente para combater os problemas associados à resistência e à toxicidade dos fármacos correntes. Neste trabalho bases de Schiff derivadas do S-metil-ditiocarbazato: SalSmdt, Mp(Smdt)2, VanSmdt, PySmdt e os seus complexos de zinco(II) foram sintetizados. As bases de Schiff foram obtidas através da condensação do S-metil-ditiocarbazato (smdt) com diferentes aldeídos aromáticos: salicilaldeído (Sal), o-vanilina (Van) pyridoxal (Py) e 2,6-diformil-4- metilfenol (Mp) em álcoois. Foram também sintetizados os complexos Zn[(phen)2(NO3)2]2H2O, Zn[(aminophen)2(NO3)2]1.5H2O e Zn[(Mephen)2(NO3)2]3.5H2O por reacção do Zn(II) com 1,10-fenantrolina (phen), 4,7-dimetil-1,10-fenantrolina (Mephen) e 5- amino-1,10-fenantolina (aminophen), respectivamente. Todos os compostos foram caracterizados por análise elementar, espectroscopia de FTIR, UV-Vis, RMN, fluorescência e espectrometria de massa. A caracterização sugere que as bases de Schiff coordenam o ião metálico através do O-fenolato, o N-imina e o átomo de enxofre na forma tiol (excepto no Zn[(PySmdt)(CH3COO)] para o qual se propõe o ligando na forma tiona). A estabilidade dos compostos foi avaliada em meio aquoso tamponizado (5 % dmso e 95 % PBS, pH=7.4) tendo-se concluído que todos os compostos são estáveis durante pelo menos 3h. O potencial antioxidante dos compostos foi testado usando um ensaio com 2,2-difenil-1-picrilhidrazil. Todas as bases de Schiff possuem actividade antioxidante moderada, mas os complexos de Zn(II) (excepto o Zn[(PySmdt)(CH3COO)]) são inactivos. Os complexos derivados das fenantrolinas foram testados quanto à sua capacidade para interagir com o ADN usando espectrofotometria de fluorescência e revelaram capacidade, sendo o Zn(aminophen) o mais activo. Encontram-se a decorrer estudos de citotoxidade com várias linhas celulares tumorais (PC-3, MCF-7 e CACO-2). Os resultados das bases de Schiff são promissores, uma vez que os IC50 são da ordem dos μM (entre 4.41 e 28.99). As fenantrolinas e seus correspondentes complexos de Zn(II) mostraram citotoxicidade muito elevada nas células tumorais A2780, com os complexos a revelarem actividade ligeiramente superior aos ligandos

AWARENESS OF OBSTETRIC DANGER SIGNS AND ASSOCIATED FACTORS AMONG PREGNANT WOMEN WHO ATTEND ANTENATAL CARE IN PUBLIC HEALTH INSTITUTIONS OF ADAMA CITY, OROMIA, ETHIOPIA

Improving awareness of women about obstetric danger signs of pregnancy, labor, and postpartum period is the crucial first step in accepting appropriate and timely health care service. In Ethiopia, where pregnancy related complications and maternal death is high, little is known about level of awareness of obstetric danger signs. The aim of this study was to assess Awareness of Obstetric Danger Signs and Associated Factors among Pregnant Women who attend Ante-natal care in Public Health Institutions of Adama City, Oromia, Ethiopia, 2018.Institutional based cross-sectional study was conducted from October 2017 to April 2018 and a total of 381 pregnant women were selected using Systematic random sampling technique. Interviewer administered structured Questionnaire was used to collect data. Data were cleaned and analyzed using EPI-INFO version 7 and SPSS window version 20. Bivariate and multi variable Logistic regression was used to assess association between awareness of obstetric danger signs and various independent variables.A total of 381 pregnant women were participated with 100% response rate. Of all participants about 44.4% knew seven and above obstetric danger signs of pregnancy, labor, and postpartum period. Out of the 381 participants 261 (68.5%), 240 (63%) and 164 (43%) knew at least two danger signs during pregnancy, childbirth and postpartum period, respectively. Vaginal bleeding was the most commonly mentioned danger signs of pregnancy (59.8%), labor (66.1%) and postpartum (60.4%). In multivariate logistic regression analysis, maternal and husband educational status, residence, and sources of obstetric danger signs related information were significantly associated with awareness of obstetric danger signs. Awareness of women about obstetric danger signs of pregnancy, labor, and postpartum period was low and affected by Partner & maternal educational status, sources of obstetric danger signs related information, and residence. Therefore, it needs to raise women’s awareness of danger signs and associated factors through maternal and child health service by designing appropriate strategies including provision of targeted information, education, and communication

Banana Xanthomonas wilt in Ethiopia: Occurrence and insect vector transmission

Bacterial wilt caused by Xanthomonas vasicola pv. musacearum (Xvm) is an important disease of enset and banana in south and south-western Ethiopia where, the diversity of the insect fauna on banana inflorescences was unknown and the role of insects as vectors of the disease had not been studied. The objectives of this study wereto assess the occurrence of bacterial wilt and male bud infection, the diversity of insect families in banana plantations and the presence of the bacteria on insects collected from diseased inflorescences in south and southwestern Ethiopia. Surveys were carried out and insects were collected from three different zones in 2005. The diversity and richness of the insect families was assessed across sites and genotypes and comparisons were made using the Shannon Diversity Index and the Jack knife estimator, respectively. Correlations were made betweenthe abundance and incidence of insects with the incidence of male bud infection on ‘Pisang Awak’ plants. A wide range of insect families were recorded and they varied according to banana genotype and altitude. The Drosophilidae and Apinae families were most frequently recorded across sites and genotypes. The ‘Wendo’ variety (AAACavendish group) had the highest diversity and richness of insect families within and across sites. In contrast to the Kembata Tembaro and Bench Maji zones, severe and widespread male bud infection of banana was found in Kaffa, where there was a high diversity of insects on the ‘Pisang Awak’ and ‘Abesha muz’ plants. The incidenceof male bud infection on ‘Pisang Awak’ plants was highly correlated with the incidence of insects (R2 = 0.964). The incidence of male bud infection however depends on the floral morphology and altitude. Artificial inoculation with Xvm ooze on fresh male bract and flower scars resulted in infections on ‘Pisang Awak’ and ‘Abesha muz’ plants, but the ‘Dwarf Cavendish’ plants with persistent bracts and flowers remained healthy. Few male bud infections were observed at altitudes above 1,700 masl. Xvm was isolated from Apinae, Lonchaeidae, Muscidae,Tephritidae and Vespidae insect families. Lonchaeidae (Silba spp.) were frequently observed on banana bract and flower scars and could thus be an important insect vector of Xvm in Ethiopia

Isolation, Identification, Antimicrobial Resistance Pattern of Salmonella and Public Awareness on Meat Hygiene at Mizan Municipal Abattoir and Butcher Houses, Southwest Ethiopia

Foodborne diseases are among the most widespread global public health problems and their implication for economy is increasingly recognized. Salmonella is the leading cause of foodborne diseases worldwide. A cross-sectional study was conducted from March to September 2019 at municipal abattoir and butcher houses of Mizan town, Ethiopia with the objectives to assess the occurrence of risk factors, antimicrobial resistance pattern of Salmonellaisolates and awareness status of meat handlers on meat hygiene and safety. A total of 320 samples consisting of 240 from abattoir (beef carcass swab = 175, abattoir personnel hand swab =25, abattoir material swab =40) and 80 from butcher houses (butcher hand swab =30, butcher material swab =50) were collected and examined for the presence of Salmonella using the standard techniques and procedures outlined by the International Organization for Standardization. The overall prevalence of Salmonella was found to be 13.4% (43/320). Out of a total isolates, 30/240 (12.5%) were isolated from abattoir source; of which 21/175 (12%) from carcass swab, 4/25 (16%) from abattoir personnel hand swab and 5/40 (12.5%) from abattoir materials swab while 13/80 (16.2%) from butcher houses source; of which 5/30 (16.6%) from butcher personnel hand swab and 8/50 (16%) from butcher materials swab. However, there was no statistically significant difference observed in the prevalence of salmonella among sample source and type (p > 0.05). Out of the total 43 isolates subjected to a panel of 8 antimicrobials, 42 (97.67%) were multiple antimicrobial resistant and the highest level of resistance was observed for erythromycin (100%), ampicillin (83.7%), oxacilin (72.09%) and neomycin (67.44%).However, all isolates were susceptible to gentamycin. Multivariable logistic regression result showed that, materials which were not cleaned (OR=12.56; 95% CI: 0.986-160; P=0.048) and people who didn’t knew contamination as risk (OR=11.5; 95% CI: 1.65-80; P=0.014) were the major risk factors for the occurrence of Salmonella among abattoir and butcher houses in the study area.Besides, the knowledge, attitude and practices of beef meat handlers (abattoir workers and butchers) were founded to be poor. Thus, urgent intervention program to minimize the risks associated for contamination of meat with Salmonella and prudent use of antimicrobialswere recommended

Luminescence and Electroanalytical Properties of Carbon Quantum Dots in the Context of Immunosensor Design

Electroanalytical techniques are powerful tools in biological sensing because of their sensitivity and versatility. In recent decades, great attention has been given to the fabrication of electroactive nanomaterial-based biosensors. In this context, carbon quantum dots (CQDs) have received special attention and have been used to develop many sensors because of their remarkable advantages such as high photostability, high solubility and stability in water, biocompatibility, high photoluminescence emission intensities, and simple methods of synthesis. Since they are very small in size, they have high surface area to volume ratios which in turn can allow good catalytic activities of the working electrodes in electrochemical reactions. Being motivated by these advantages, in this work we prepared two types of carbon quantum dots (CQD-COOH and CQD-NH2) and used them to modify screen printed carbon electrodes (SPCEs) for detection of Troponin I (cTnI). These carbon quantum dot – modified SPCE immunosensors have offered promising results for the determination of cTnI with a limit of detection 62 pg/mL and 171 pg/mL, respectively. This simple approach to sensor design further offers valuable insights into the construction of paper based printed electrodes modified with new carbon-based nanomaterials as immunosensors for detection of other biomarkers of various diseases

Effect of malaria on HIV/AIDS transmission and progression

Malaria and HIV are among the two most important global health problems of developing countries. They cause more than 4 million deaths a year. These two infections interact bidirectionally and synergistically with each other. HIV infection increases the risk of an increase in the severity of malaria infection and burdens of malaria, which in turn facilitates the rate of malaria transmission. Malaria infection is also associated with strong CD4+ cell activation and up-regulation of proinflammatory cytokines and it provides an ideal microenvironment for the spread of the virus among the CD4+ cells and for rapid HIV-1 replication. Additionally, malaria increases blood viral burden by different mechanisms. Therefore, high concentrations of HIV-1 RNA in the blood are predictive of disease progression, and correlate with the risk of blood-borne, vertical, and sexual transmission of the virus. Therefore, this article aims to review information about HIV malaria interactions, the effect of malaria on HIV transmission and progression and the implications related to prevention and treatment of coinfection

The Global Trachoma Mapping Project: Methodology of a 34-Country Population-Based Study.

PURPOSE: To complete the baseline trachoma map worldwide by conducting population-based surveys in an estimated 1238 suspected endemic districts of 34 countries. METHODS: A series of national and sub-national projects owned, managed and staffed by ministries of health, conduct house-to-house cluster random sample surveys in evaluation units, which generally correspond to "health district" size: populations of 100,000-250,000 people. In each evaluation unit, we invite all residents aged 1 year and older from h households in each of c clusters to be examined for clinical signs of trachoma, where h is the number of households that can be seen by 1 team in 1 day, and the product h × c is calculated to facilitate recruitment of 1019 children aged 1-9 years. In addition to individual-level demographic and clinical data, household-level water, sanitation and hygiene data are entered into the purpose-built LINKS application on Android smartphones, transmitted to the Cloud, and cleaned, analyzed and ministry-of-health-approved via a secure web-based portal. The main outcome measures are the evaluation unit-level prevalence of follicular trachoma in children aged 1-9 years, prevalence of trachomatous trichiasis in adults aged 15 + years, percentage of households using safe methods for disposal of human feces, and percentage of households with proximate access to water for personal hygiene purposes. RESULTS: In the first year of fieldwork, 347 field teams commenced work in 21 projects in 7 countries. CONCLUSION: With an approach that is innovative in design and scale, we aim to complete baseline mapping of trachoma throughout the world in 2015

An IPM guide for enset root mealybug (Cataenococcus ensete) in enset production

This guide has been produced as an overview of a body of work that aims to help mitigate the threat of Enset mealybug: the biology and description of Enset mealybug; its behaviour; its geographical distribution; the pest symptoms; the list of mealybug dispersal methods, and the means of mealybug management, including prevention (clean planting material, extension, affordable management, quarantine, hygiene and ant control), cultural control (farmyard manure, hot water treatment, cultivation), biological control, use of insecticidal plant extracts (botanicals), and agrochemical control

Dyslipidemia and associated factors among adult type two diabetes mellitus patients in Felege Hiywot Refral, Hospital, Bahir Dar, Ethiopia, 2023

BackgroundDyslipidemia is a common condition in type two diabetic patients, and it is thought to have a significant role in moderating the cardiovascular risk associated with diabetes. Data on serum lipid profiles in type 2 diabetes patients from Bahir Dar, Ethiopia is limited. This study aimed to evaluate the prevalence of dyslipidemia among adult type 2 diabetes patients and to explore potential contributing factors.Method and materialsA facility-based cross-sectional study was conducted with 354 type 2 diabetes mellitus patients from April 3 to June 4, 2023. Data were collected through the use of structured questionnaires and checklists. The data were entered into EpiData version 4.6 and analyzed using SPSS version 26. Logistic regression was employed to identify variables significantly associated with the outcomes, with a p-value ≤ 0.05 and a 95% confidence interval.ResultsA total of 369 individuals with diabetes were approached in this study, resulting in a response rate of 96%. The overall prevalence of dyslipidemia was 61.3% (95% CI: 56.2–66.7). Of those with dyslipidemia, 11% had a single serum lipid abnormality, while 50.3% had a combined serum lipid abnormality. Significant factors associated with dyslipidemia included being over 60 years old (AOR: 2.4, 95% CI: 1.2–5.0), poor fasting blood glucose control (AOR: 2.5, 95% CI: 1.2–5.1), being overweight (AOR: 5.8, 95% CI: 3.2–11), physical inactivity (AOR: 3.4, 95% CI: 1.7–7.0), and being a past alcohol drinker (AOR: 3.1, 95% CI: 1.3–7.4).ConclusionIn the study area, a high prevalence of dyslipidemia was found among diabetic patients. Independent factors associated with dyslipidemia included older age, poor fasting blood glucose control, physical inactivity, a history of alcohol consumption, and being overweight. To address this issue, it is essential to implement preventive measures such as early detection, patient education, dietary monitoring, regular clinical visits, physical exercise, and weight management. These strategies represent the most effective approach to combating dyslipidemia