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1.
Front Cell Infect Microbiol ; 14: 1382289, 2024.
Article in English | MEDLINE | ID: mdl-38638827

ABSTRACT

Pseudomonas aeruginosa belongs to the critical pathogens that represent a global public health problem due to their high rate of resistance as listed by WHO. P. aeruginosa can result in many nosocomial infections especially in individuals with compromised immune systems. Attenuating virulence factors by interference with quorum sensing (QS) systems is a promising approach to treat P. aeruginosa-resistant infections. Thymoquinone is a natural compound isolated from Nigella sativa (black seed) essential oil. In this study, the minimum inhibitory concentration of thymoquinone was detected followed by investigating the antibiofilm and antivirulence activities of the subinhibitory concentration of thymoquinone against P. aeruginosa PAO1. The effect of thymoquinone on the expression of QS genes was assessed by quantitative real-time PCR, and the protective effect of thymoquinone against the pathogenesis of PAO1 in mice was detected by the mouse survival test. Thymoquinone significantly inhibited biofilm, pyocyanin, protease activity, and swarming motility. At the molecular level, thymoquinone markedly downregulated QS genes lasI, lasR, rhlI, and rhlR. Moreover, thymoquinone could protect mice from the pathologic effects of P. aeruginosa increasing mouse survival from 20% to 100%. In conclusion, thymoquinone is a promising natural agent that can be used as an adjunct therapeutic agent with antibiotics to attenuate the pathogenicity of P. aeruginosa.


Subject(s)
Benzoquinones , Biofilms , Pseudomonas aeruginosa , Animals , Mice , Virulence/genetics , Quorum Sensing , Virulence Factors/metabolism , Anti-Bacterial Agents/pharmacology , Bacterial Proteins/metabolism
2.
Sci Rep ; 13(1): 18684, 2023 Oct 31.
Article in English | MEDLINE | ID: mdl-37907656

ABSTRACT

Natural resources including sand are one of the best approaches for treating dye-polluted wastewater. The SiO2/PANI-SDS nanocomposite was synthesized by self-assembly and intermolecular interaction. The physicochemical features of the SiO2/PANI-SDS nanocomposite were explored by FT-IR, XRD, SEM, TEM, EDX, and N2 adsorption-desorption techniques to be evaluated as an adsorbent for the MB. The surface area of the SiO2/PANI-SDS is 23.317 m2/g, the pore size is 0.036 cm3/g, and the pore radius is 1.91 nm. Batch kinetic studies at different initial adsorbate, adsorbent and NaCl concentrations, and temperatures showed excellent pseudo-second-order. Several isotherm models were applied to evaluate the MB adsorption on the SiO2/PANI-SDS nanocomposite. According to R2 values the isotherm models were fitted in the following order: Langmuir > Dubinin-Radushkevich (D-R) > Freundlich. The adsorption/desorption process showed good reusability of the SiO2/PANI-SDS nanocomposite.

3.
Saudi Dent J ; 35(6): 575-588, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37823084

ABSTRACT

Studies assessing the clinical and radiographic success of LSTR in terms of the presence of pain, mobility, swelling, fistula/sinus tract, interradicular radiolucency, and root resorption have not been performed. We therefore performed a systematic review with the aim of evaluating the effectiveness of lesion sterilization and tissue repair (LSTR), using three antibacterial mixtures (3Mix), in treating primary teeth. Well-defined search strategies developed for four electronic databases, Web of Science, OVID, PubMed, and Scopus, were used in this study. Two independent reviewers selected relevant articles from 3,232 studies by screening titles and abstracts. Based on the inclusion criteria, 25 articles were selected. Eight analyses of clinical and radiographic results were conducted based on 6, 12, 18, and 24-month follow-up intervals. Data extraction and quality appraisal were performed by three independent reviewers. The composition of antibiotic mixtures used for LSTR varied substantially, with inconsistent radiographic and clinical success rates across the included studies. A quantitative grouping of the studies showed no significant differences between 3Mix and the control medicaments regarding radiographical and clinical success (p-value > 0.05). The available evidence on different LSTR using 3Mix is scarce, and the study findings were inconsistent. Therefore, additional clinical trials on 3Mix with different compositions are needed.

4.
Environ Sci Pollut Res Int ; 30(49): 106822-106837, 2023 Oct.
Article in English | MEDLINE | ID: mdl-36752924

ABSTRACT

Cationic ligand exchange is one of the most predominant mechanisms for the removal of ammonia from wastewater through complex formation. The complexation technique occurs between the metal ions loaded on the surface of Amberlite IR-120 and ammonia which is present in the medium. Cu(II)-loaded Amberlite IR-120 (R-Cu2+) was prepared and described using FT-IR, TGA, SEM, and EDX techniques. The prepared R-Cu2+ was applied for the elimination of ammonia from an aqueous solution. Different cations such as Co2+ and Ni2+ were loaded onto Amberlite IR-120 to study the impact of counter cation on the removal efficiency of ammonia. The ammonia removal percentage followed the order; R-Cu2+ > R-Ni2+ > R-Co2+. The effects of contact time, pH, initial concentration, temperature, and coexisting ions on the removal of ammonia from wastewater by R-Cu2+ were investigated. The equilibrium adsorbed amount of ammonia was found to be 200 mg/g at pH = 8.6 and 303 K within 60 min using 0.1 g R-Cu2+ and an initial concentration of ammonia of 1060 mg/L. The removal of ammonia using R-Cu2+ obeyed the non-linear plot of both Freundlich and Langmuir isotherms. According to the thermodynamic parameters, the adsorption of ammonia onto R-Cu2+ was an endothermic and spontaneous process. The time-adsorption data followed the pseudo-second-order and intraparticle diffusion models. Moreover, the resulting product (R-Cu(II)-amine composite) from the adsorption process exhibited high catalytic activity and could be low-cost material for the elimination of dyes such as aniline blue (AB), methyl green (MG), and methyl violet 2B (MV2B) from wastewater.


Subject(s)
Wastewater , Water Pollutants, Chemical , Copper , Ammonia , Spectroscopy, Fourier Transform Infrared , Coloring Agents , Ions , Adsorption , Kinetics , Hydrogen-Ion Concentration , Water Pollutants, Chemical/analysis
5.
J Enzyme Inhib Med Chem ; 38(1): 203-215, 2023 Dec.
Article in English | MEDLINE | ID: mdl-36382444

ABSTRACT

The present study aimed to investigate the antitumor effect of simultaneous inhibition of dihydrofolate reductase (DHFR) enzyme. We designed some novel pyrazolo[3,4-d]pyrimidines bearing different amino acid conjugates as efficient antifolate agents attributable to their structural similarity with methotrexate (MTX) and MTX-related antifolates. All compounds were tested to screen their enzymatic inhibition against DHFR compared with the reference drug MTX and for their in vitro antitumor cytotoxicity against six MTX-resistant cancer cell lines. The flow cytometry indicated that the most potent compound 7f arrested MCF-7 cells in the S-phase and induced apoptosis. Western blot for visualisation proved the ability of compound 7f to induce the expression of proapoptotic caspases and Bax proteins in MCF-7 breast cancer cell line beside its ability to diminish the expression of antiapoptotic Bcl-2 protein. Molecular modelling studies concluded that compound 7f displayed better binding energy than that of the normal ligand MTX. HIGHLIGHTSNew pyrazolo[3,4-d]pyrimidine derivatives 7a-m which are structurally similar to the classical methotrexate (MTX) and MTX-related antifolates were synthesised as antitumor agents.Novel N-acyl amino acid compound 7f exhibited marked DHFR inhibition activity that are parralel to both the molecular docking results and cytotoxic activity.Compound 7f could induce the expression of proapoptotic caspases and Bax proteins in MCF-7 breast cancer cell line beside its ability to diminish the expression of antiapoptotic Bcl-2 protein.All prepared compounds obey Lipinski rule of five except compound 7f.


Subject(s)
Antineoplastic Agents , Breast Neoplasms , Folic Acid Antagonists , Humans , Female , Pyrimidines/chemistry , bcl-2-Associated X Protein , Methotrexate/pharmacology , Molecular Docking Simulation , Drug Screening Assays, Antitumor , Amino Acids , Structure-Activity Relationship , Tetrahydrofolate Dehydrogenase/metabolism , Antineoplastic Agents/chemistry , Breast Neoplasms/drug therapy , Caspases/metabolism
6.
Photochem Photobiol Sci ; 22(3): 579-594, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36434430

ABSTRACT

A comparison study examines six different metal oxides (CuO, ZnO, Fe3O4, Co3O4, NiO, and α-MnO2) for the degradation of malachite green dye using four distinct processes. These processes are as follows: sonocatalysis (US/metal oxide), sonocatalysis under ultra-violet irradiation (US/metal oxide/UV), sonocatalysis in the presence of hydrogen peroxide (US/metal oxide/H2O2), and a combination of all these processes (US/metal oxide/UV/H2O2). The effective operating parameters, such as the dosage of metal oxide nanoparticles (MONPs), the type of the process, and the metal oxides' efficiency order, were studied. At the same reaction conditions, the sonophotocatalytic is the best process for all six MOsNPs, CuO was the better metal oxide than other MOsNPs, and at the sonocatalysis process, ZnO was the best metal oxide in other processes. It was found that the metal oxide order for sonocatalytic process is CuO > α-MnO2 ≥ ZnO > NiO ≥ Fe3O4 ≥ Co3O4 within 15-45 min. The order of (US/metal oxide/UV) process is ZnO ≥ NiO ≥ α-MnO2 > Fe3O4 ≥ CuO ≥ Co3O4 within 5-40 min. The order of (US/ MOsNPs/ H2O2) process is ZnO ≥ CuO ≥ α-MnO2 ≥ NiO > Co3O4 > Fe3O4 within 5-20 min. The maximum removal efficiency order of the sonophotocatalytic process is ZnO ≥ CuO > α-MnO2 > NiO > Fe3O4 ≥ Co3O4 within 2-8 min. The four processes degradation efficiency was in the order US/MOsNPs ˂ US/MOsNPs/UV ˂ US/MOsNPs/H2O2 ˂ (UV/Ultrasonic/MOsNPs/H2O2). Complete degradation of MG was obtained at 0.05 g/L MONPs and 1 mM of H2O2 using 296 W/L ultrasonic power and 15 W ultra-violet lamp (UV-C) within a reaction time of 8 min according to the MOsNPs type at the same sonophotocatalytic/H2O2 reaction conditions. The US/metal oxide/UV/H2O2 process is inexpensive, highly reusable, and efficient for degrading dyes in colored wastewater.

7.
Bioorg Chem ; 129: 106207, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36270170

ABSTRACT

A new series of pyrazolo[3,4-d]pyrimidine analogues bearing different amino acid conjugates 10a-m were synthesized with the aim to evaluate their antitumor effect through simultaneous inhibition of human dihydrofolate reductase (hDHFR). All novel compounds were tested to screen their enzyme inhibition activity against (hDHFR) beside their in vitro cytotoxicity against six human MTX resistant cancer cell lines namely, human prostate cancer (PC-3), pancreatic human cancer cell lines (BxPC-3), colorectal carcinoma (HCT-116), human hepatocellular carcinoma (HepG-2), cervical carcinoma (HeLa), and mammary gland breast cancer (MCF-7), besides normal immortalized pancreatic cell line (HPDE). Compounds 10e, 10f, 10g inhibited DHFR at considerable low (IC50 < 1 µM) in comparison to MTX (IC50 = 5.61 µM) beside their characteristic cytotoxic effects on different resistant cancer cell lines. Flow cytometry was done for the most active candidate compound 10e against MCF-7 breast cancer cell line. The results illustrated that compound 10e induced apoptosis and arrested MCF-7 cell cycle in the G1/S phase. Western blot for visualization and quantification was used to confirm the capability of compound 10e to induce the expression of proapoptotic caspases and Bax proteins in MCF-7 breast cancer cell line beside its ability to reduce the expression of antiapoptotic Bcl-2 protein. Molecular modeling studies demonstrated that compound 10e elucidated binding energy of (S= - 8.4390 Kcal/mol) that exceed that of the normal ligand MTX (S= - 8.3951Kcal/mol) in addition to several favorable binding interactions with the active site residues.


Subject(s)
Antineoplastic Agents , Folic Acid Antagonists , Pyrazoles , Pyrimidines , Tetrahydrofolate Dehydrogenase , Female , Humans , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Cell Line, Tumor , Cell Proliferation , Drug Screening Assays, Antitumor , Molecular Structure , Pyrimidines/chemical synthesis , Pyrimidines/chemistry , Pyrimidines/pharmacology , Structure-Activity Relationship , Tetrahydrofolate Dehydrogenase/metabolism , Folic Acid Antagonists/chemical synthesis , Folic Acid Antagonists/chemistry , Folic Acid Antagonists/pharmacology , Pyrazoles/chemical synthesis , Pyrazoles/chemistry , Pyrazoles/pharmacology
8.
Antibiotics (Basel) ; 11(4)2022 Mar 30.
Article in English | MEDLINE | ID: mdl-35453216

ABSTRACT

Salmonella enterica is an invasive intracellular pathogen and hires diverse systems to manipulate its survival in the host cells. Salmonella could eavesdrop on the host cells, sensing and responding to the produced adrenergic hormones and other neurotransmitters, which results in the augmentation of its virulence and establishes its accommodation in host cells. The current study aims to assess the anti-virulence effect of α-adrenergic antagonist terazosin on S. Typhimurium. Our findings show that terazosin significantly reduced S. Typhimurium adhesion and biofilm formation. Furthermore, terazosin significantly decreased invasion and intracellular replication of S. Typhimurium. Interestingly, in vivo, terazosin protected the mice from S. Typhimurium pathogenesis. To understand the terazosin anti-virulence activity, its effect on quorum sensing (QS), bacterial espionage, and type three secretion system (T3SS) was studied. Strikingly, terazosin competed on the membranal sensors that sense adrenergic hormones and down-regulated their encoding genes, which indicates the ability of terazosin to diminish the bacterial eavesdropping on the host cells. Moreover, terazosin significantly reduced the Chromobacterium violaceum QS-controlled pigment production and interfered with the QS receptor Lux-homolog Salmonella SdiA, which indicates the possible terazosin-mediated anti-QS activity. Furthermore, terazosin down-regulated the expression of T3SS encoding genes. In conclusion, terazosin may mitigate S. Typhimurium virulence owing to its hindering QS and down-regulating T3SS encoding genes besides its inhibition of bacterial espionage.

9.
Sensors (Basel) ; 21(3)2021 Jan 28.
Article in English | MEDLINE | ID: mdl-33525462

ABSTRACT

Monitoring wild ungulates such as deer is a highly challenging issue faced by wildlife managers. Wild ungulates are increasing in number worldwide, causing damage to ecosystems. For effective management, the precise estimation of their population size and habitat is essential. Conventional methods used to estimate the population density of wild ungulates, such as the light census survey, are time-consuming with low accuracy and difficult to implement in harsh environments like muddy wetlands. On the other hand, unmanned aerial vehicles are difficult to use in areas with dense tree cover. Although the passive acoustic monitoring of animal sounds is commonly used to evaluate their diversity, the potential for detecting animal positions from their sound has not been sufficiently investigated. This study introduces a new technique for detecting and tracking deer position in the wild using sound recordings. The technique relies on the time lag among three recorders to estimate the position. A sound recording system was also developed to overcome the time drift problem in the internal clock of recorders, by receiving time information from GPS satellites. Determining deer position enables the elimination of repetitive calls from the same deer, thus providing a promising tool to track deer movement. The validation results revealed that the proposed technique can provide reasonable accuracy for the experimental and natural environment. The identification of deer calls in Oze National Park over a period of two hours emphasizes the great potential of the proposed technique to detect repetitive deer calls, and track deer movement. Hence, the technique is the first step toward designing an automated system for estimating the population of deer or other vocal animals using sound recordings.


Subject(s)
Deer , Vocalization, Animal , Animals , Animals, Wild , Ecosystem
10.
Pharmaceuticals (Basel) ; 13(9)2020 Sep 18.
Article in English | MEDLINE | ID: mdl-32961906

ABSTRACT

The membrane-bound human carbonic anhydrase (hCA) IX is widely recognized as a marker of tumor hypoxia and a prognostic factor within several human cancers. Being undetected in most normal tissues, hCA-IX implies the pharmacotherapeutic advent of reduced off-target adverse effects. We assessed the potential anticancer activity of bumetanide-based analogues to inhibit the hCA-IX enzymatic activity and cell proliferation of two solid cancer cell lines, namely kidney carcinoma (A-498) and bladder squamous cell carcinoma (SCaBER). Bumetanide analogues efficiently inhibit the target hCA-IX in low nanomolar activity (IC50 = 4.4-23.7 nM) and have an excellent selectivity profile (SI = 14.5-804) relative to the ubiquitous hCA-II isoform. Additionally, molecular docking studies provided insights into the compounds' structure-activity relationship and preferential binding of small-sized as well as selective bulky ligands towards the hCA-IX pocket. In particular, 2,4-dihydro-1,2,4-triazole-3-thione derivative 9c displayed pronounced hCA-IX inhibitory activity and impressive antiproliferative activity on oncogenic A-498 kidney carcinoma cells and is being considered as a promising anticancer candidate. Future studies will aim to optimize this compound to fine-tune its anticancer activity as well as explore its potential through in-vivo preclinical studies.

11.
Bioorg Chem ; 100: 103878, 2020 07.
Article in English | MEDLINE | ID: mdl-32361486

ABSTRACT

Herein, we describe the design and synthesis of new benzenesulfonamide derivatives as selective COX-2 inhibitors based on bumetanide scaffold. Benzenesulfonamides bearing both the pyrazole 6b and the triazoles 9a, 9c were good inhibitors of COX-2 with IC50 values of 0.32, 0.28 and 0.17 µM, respectively. These benzenesulfonamides 6b, 9a and 9c exhibited a higher selectivity index than the reference drug celecoxib. Molecular modeling study showed that incorporation of bumetanide led to a unique binding mode that is most likely the reason for the observed significant COX-2 selectivity. The anti-inflammatory activity of synthesized compounds revealed that triazoles 9a and 9c demonstrated higher efficacy than celecoxib upon using in vivo carrageenan-induced rat paw edema model. Most of the prepared compounds possess low ulcerogenic potential when administered orally. Therefore, these compounds have a great potential to be developed as safe therapeutics for inflammation, pain, and other diseases where COX-2 plays important role in their pathophysiology.


Subject(s)
Anti-Inflammatory Agents/chemistry , Anti-Inflammatory Agents/pharmacology , Bumetanide/analogs & derivatives , Bumetanide/pharmacology , Cyclooxygenase 2 Inhibitors/chemistry , Cyclooxygenase 2 Inhibitors/pharmacology , Animals , Anti-Inflammatory Agents/chemical synthesis , Anti-Inflammatory Agents/therapeutic use , Bumetanide/chemical synthesis , Bumetanide/therapeutic use , Catalytic Domain/drug effects , Cyclooxygenase 2/chemistry , Cyclooxygenase 2/metabolism , Cyclooxygenase 2 Inhibitors/chemical synthesis , Cyclooxygenase 2 Inhibitors/therapeutic use , Drug Design , Edema/drug therapy , Edema/metabolism , Male , Mice , Molecular Docking Simulation , Rats , Sulfonamides/chemical synthesis , Sulfonamides/chemistry , Sulfonamides/pharmacology , Sulfonamides/therapeutic use , Benzenesulfonamides
12.
Indian J Nephrol ; 30(1): 21-25, 2020.
Article in English | MEDLINE | ID: mdl-32015595

ABSTRACT

INTRODUCTION: Diabetic nephropathy (DN) is the most common cause of chronic kidney disease worldwide. A major challenge is to identify early diabetic nephropathy. microRNAs (miRNAs) are short noncoding RNA sequences and regulate a wide range of biological processes as cell differentiation, proliferation, cell metabolism and apoptosis. miRNAs may have a role in molecular mechanisms linked to cellular pathways of DN. The aim of this study was to investigate the level of microRNA-21 as a potential marker of early nephropathy in type 1 diabetes mellitus (T1DM). METHODS: A total number of 340 participants were included and classified into 3 groups; Group I included 100 healthy participants, Group II included 120 patients with T1DM with <5 years duration, and Group III included 120 patients with T1DM with >5 years duration. All participants were submitted to detail clinical examination, laboratory investigations, urinary albumin/creatinine ratio (ACR), estimated glomerular filtration rate (eGFR) as well as plasma microRNA-21 assays. RESULTS: Blood pressure and ACR were significantly higher in group III than groups I and II. Further, microRNA-21 was significantly higher in group III than groups I and II, and more in group II than group I. microRNA-21 starts to rise in group II before microalbuminuria. miRNA-21 at a level of 0.01 had a greater sensitivity 94.1% and specificity 100% for identifying DN than ACR at level 45 mg/gm with sensitivity 88.2% and specificity 89%. CONCLUSION: Plasma microRNA-21 can serve as an early marker for diagnosis and identifying diabetic nephropathy in T1DM.

13.
Spectrochim Acta A Mol Biomol Spectrosc ; 227: 117618, 2020 Feb 15.
Article in English | MEDLINE | ID: mdl-31699590

ABSTRACT

The kinetics of the homogeneous and heterogeneous catalytic oxidation processes of three azo dyes in presence of copper (II) - ions, copper (II) - ions - supported on alumina and on zinc oxide as well as copper ammonia complex supported on alumina were investigated in aqueous solutions. The dyes are Chromotrope 2B (C2B), Chromotrope 2R (C2R) and Chrysophenen (CRY). The reaction progress was followed by monitoring the decrease in absorbance at ℷmax 512, 511 and 401 nm, respectively. The rate of reaction increased with increasing either the concentration of the dye or the catalyst, giving a plateau at high concentrations of the catalyst. On the other hand, the rate of reaction increased gradually with increasing hydrogen peroxide concentration attaining a maximum then decreased thereafter. The reaction rate was also increased with increasing pH and temperature and was found to be entropy controlled. This work could be applied for dye baths water reuse to reduce costs in textile and dyeing factories as will as for environmental purposes.

14.
J Musculoskelet Neuronal Interact ; 19(4): 500-506, 2019 12 01.
Article in English | MEDLINE | ID: mdl-31789301

ABSTRACT

OBJECTIVE: To evaluate the effect of simultaneous proprioceptive - visual training on gait parameters in children with spastic diplegic cerebral palsy. METHOD: Gait parameters of 30 spastic diplegic children (age range 4-6 years) were evaluated before and after treatment by Tekscan's Walkway Pressure system. They were randomly and equally assigned into two groups (study and control). All children received regular therapeutic exercise program for one hour. In control group walked for 30 minutes without feedback, while those in study group walked for 30 minutes with proprioceptive-visual feedback. Duration of treatment was 3 times/week for 8 successive weeks. RESULTS: There were significant differences after treatment in spatial parameters and temporal parameters of both groups with more improvement in study group than control one, and insignificant difference in kinetic gait parameters. CONCLUSION: The simultaneous proprioceptive - visual training might improve spatial and temporal gait parameters with no effect on kinetic gait parameters of children with spastic diplegic cerebral palsy.


Subject(s)
Cerebral Palsy/rehabilitation , Feedback, Sensory/physiology , Gait/physiology , Muscle Spasticity/rehabilitation , Physical Therapy Modalities , Proprioception/physiology , Visual Perception/physiology , Cerebral Palsy/physiopathology , Child , Child, Preschool , Female , Humans , Male , Muscle Spasticity/physiopathology , Postural Balance/physiology , Treatment Outcome , Walking/physiology
15.
PLoS Negl Trop Dis ; 13(6): e0007314, 2019 06.
Article in English | MEDLINE | ID: mdl-31194743

ABSTRACT

BACKGROUND: The Mediterranean Basin is historically a hotspot for trade, transport, and migration. As a result, countries surrounding the Mediterranean Sea share common public health threats. Among them are vector-borne diseases, and in particular, mosquito-borne viral diseases are prime candidates as (re)emerging diseases and are likely to spread across the area. Improving preparedness and response capacities to these threats at the regional level is therefore a major issue. The implementation of entomological surveillance is, in particular, of utmost importance. Guidance in designing entomological surveillance systems is critical, and these systems may pursue different specific objectives depending on the disease. The purpose of the proposed review is to draw up guidelines for designing effective and sustainable entomological surveillance systems in order to improve preparedness and response. However, we make it clear that there is no universal surveillance system, so the thinking behind harmonisation is to define evidence-based standards in order to promote best practises, identify the most appropriate surveillance activities, and optimise the use of resources. Such guidance is aimed at policymakers and diverse stakeholders and is intended to be used as a framework for the implementation of entomological surveillance programmes. It will also be useful to collaborate and share information with health professionals involved in other areas of disease surveillance. Medical entomologists and vector control professionals will be able to refer to this report to advocate for tailored entomological surveillance strategies. The main threats targeted in this review are the vectors of dengue virus, chikungunya virus, Zika virus, West Nile virus, and Rift Valley fever virus. The vectors of all these arboviruses are mosquitoes. METHODS: Current knowledge on vector surveillance in the Mediterranean area is reviewed. The analysis was carried out by a collaboration of the medical entomology experts in the region, all of whom belong to the MediLabSecure network, which is currently funded by the European Union and represents an international effort encompassing 19 countries in the Mediterranean and Black Sea region. FINDINGS: Robust surveillance systems are required to address the globalisation of emerging arboviruses. The prevention and management of mosquito-borne viral diseases must be addressed in the prism of a One Health strategy that includes entomological surveillance as an integral part of the policy. Entomological surveillance systems should be designed according to the entomological and epidemiological context and must have well-defined objectives in order to effect a tailored and graduated response. We therefore rely on different scenarios according to different entomological and epidemiological contexts and set out detailed objectives of surveillance. The development of multidisciplinary networks involving both academics and public authorities will provide resources to address these health challenges by promoting good practises in surveillance (identification of surveillance aims, design of surveillance systems, data collection, dissemination of surveillance results, evaluation of surveillance activities) and through the sharing of effective knowledge and information. These networks will also contribute to capacity building and stronger collaborations between sectors at both the local and regional levels. Finally, concrete guidance is offered on the vector of the main arbovirus based on the current situation in the area.


Subject(s)
Disease Transmission, Infectious , Epidemiological Monitoring , Insect Vectors/growth & development , Insect Vectors/virology , Virus Diseases/transmission , Viruses/isolation & purification , Animals , Humans , Insect Vectors/classification , Mediterranean Region , Viruses/classification
16.
Sensors (Basel) ; 17(8)2017 Jul 31.
Article in English | MEDLINE | ID: mdl-28758984

ABSTRACT

Numerous algorithms have been proposed to retrieve chlorophyll-a concentrations in Case 2 waters; however, the retrieval accuracy is far from satisfactory. In this research, seven algorithms are assessed with different band combinations of multispectral and hyperspectral bands using linear (LN), quadratic polynomial (QP) and power (PW) regression approaches, resulting in altogether 43 algorithmic combinations. These algorithms are evaluated by using simulated and measured datasets to understand the strengths and limitations of these algorithms. Two simulated datasets comprising 500,000 reflectance spectra each, both based on wide ranges of inherent optical properties (IOPs), are generated for the calibration and validation stages. Results reveal that the regression approach (i.e., LN, QP, and PW) has more influence on the simulated dataset than on the measured one. The algorithms that incorporated linear regression provide the highest retrieval accuracy for the simulated dataset. Results from simulated datasets reveal that the 3-band (3b) algorithm that incorporate 665-nm and 680-nm bands and band tuning selection approach outperformed other algorithms with root mean square error (RMSE) of 15.87 mg·m-3, 16.25 mg·m-3, and 19.05 mg·m-3, respectively. The spatial distribution of the best performing algorithms, for various combinations of chlorophyll-a (Chla) and non-algal particles (NAP) concentrations, show that the 3b_tuning_QP and 3b_680_QP outperform other algorithms in terms of minimum RMSE frequency of 33.19% and 60.52%, respectively. However, the two algorithms failed to accurately retrieve Chla for many combinations of Chla and NAP, particularly for low Chla and NAP concentrations. In addition, the spatial distribution emphasizes that no single algorithm can provide outstanding accuracy for Chla retrieval and that multi-algorithms should be included to reduce the error. Comparing the results of the measured and simulated datasets reveal that the algorithms that incorporate the 665-nm band outperform other algorithms for measured dataset (RMSE = 36.84 mg·m-3), while algorithms that incorporate the band tuning approach provide the highest retrieval accuracy for the simulated dataset (RMSE = 25.05 mg·m-3).


Subject(s)
Algorithms , Calibration , Chlorophyll , Environmental Monitoring , Linear Models
17.
J Vector Ecol ; 42(1): 120-129, 2017 06.
Article in English | MEDLINE | ID: mdl-28504444

ABSTRACT

The diversity, ecology, and seasonality for sand flies from two localities in Jenin District, the Palestinian Territories, were studied. A total of 12,579 sand flies (5,420 Phlebotomus and 7,159 Sergentomyia) were collected during the study period. The genera Phlebotomus and Sergentomyia are represented by 13 and nine species and subspecies, respectively. Species account was given for all collected species. CDC light traps yielded 7,649 (60.8%) of the total captured sand flies, while sticky traps and aspirators contributed to 36.4 and 2.8% of the total collected specimens, respectively. Phlebotomus sergenti and P. syriacus showed two peaks, one in July and one in October. Phlebotomus tobbi showed one peak towards the end of the summer in September and August, while P. papatasi showed a bimodal peaks pattern, one in June and one in October. Phlebotomus canaaniticus showed a peak in August. P. perfiliewi transcaucasicus and P. neglectus showed a peak in October. Sergentomyia dentata showed one peak in August and increasing numbers from June to August, declining afterwards. Other species, such as S. theodori, had one peak in June, S. taizi had steady numbers across the summer, and S. christophersi had a peak in August.


Subject(s)
Psychodidae , Seasons , Animals , Ecology , Middle East , Phlebotomus
18.
J Fluoresc ; 25(2): 379-85, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25656068

ABSTRACT

The fluorescence quenching N,N-bis(2,6-dimethylphenyl)-3,4:9,10-perylenetetra-carboxylic diimide (BDPD) by colloidal silver nanoparticles (AgNPs) was studied in methanol and ethylene glycol by steady state fluorescence measurements. The Stern-Volmer quenching rate constant (Ksv) was calculated as 8.1 × 10(8) and 8.22 × 10(8) M(-1) in methanol and ethylene glycol respectively. Taking the fluorescence lifetime of BDPD in the absence of silver nanoparticles as 3.2 ns, the values of the fluorescence quenching rate constants (kq = Ksv/τ) are calculated as 2.54 × 10(17) and 2.56 × 10(17) M(-1) s(-1) in methanol and ethylene glycol respectively. From the data, fluorescence resonance energy transfer and / or electron transfer processes play a major role in the fluorescence quenching of BDPD by AgNPs in methanol and low concentrations of Ag NPs in ethylene glycol. The static quenching rate constant in ethylene glycol was calculated by modified Stern-Volmer equation as V = 8.86 × 10(9) M(-1). For dynamic quenching, the radius of quenching sphere volume r values were found to be 68.3 and 70.6 nm in ethanol and ethylene glycol, respectively. For static quenching in ethylene glycol the effective radius of quenching sphere action (kinetic radius) was calculated as r = 152 nm.

19.
Article in English | MEDLINE | ID: mdl-25554962

ABSTRACT

The kinetics of decolorization of Chromotrope 2R (C2R) was studied spectrophotometrically using the montmorilloniteK10-Cu(II)ethylenediamine composite (MMTK10-Cu(en)2) as catalyst and H2O2 as oxidant in aqueous solution. The catalyst was prepared and characterized by SEM, FTIR, XRD and TGA techniques. The dependence of reaction rate on H2O2 concentration was examined under UV irradiation in the presence and absence of the catalyst, and in the presence of the catalyst without the UV irradiation. In all these reaction systems, the rate increased up to a maximum value and then decreased. The rate increased with increasing the concentration of the dye reaching a maximum. Also, the rate of decolorization reaction showed a significant increase with increasing the amount of the catalyst and temperature. The addition of NaCl to the reaction medium has accelerated the rate effectively. A similar catalyst, MMTKSF-Cu(en)2, has also been employed and was found to be less efficient compared with MMTK10-Cu(en)2.


Subject(s)
Bentonite/chemistry , Copper/chemistry , Ethylenediamines/chemistry , Hydrogen Peroxide/chemistry , Naphthalenesulfonates/chemistry , Catalysis , Color , Free Radical Scavengers/chemistry , Kinetics , Sodium Chloride/chemistry , Solutions , Spectroscopy, Fourier Transform Infrared , Temperature , Thermogravimetry , X-Ray Diffraction
20.
J Fluoresc ; 25(1): 103-12, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25618463

ABSTRACT

The spectral and photophysical properties of a new chalcone derivative (2E)-3-[4-(dimethylamino) phenyl]-1-(naphthalen-1-yl) prop-2-en-1-one (DPNP) containing donor-acceptor group has been synthesized and characterized on the basis of the spectral (IR, (1)HNMR & (13)C NMR) and X- ray crystallographic data. The effect of solvents on photophysical parameters such as singlet absorption, molar absorptivity, oscillator strength, dipole moment, fluorescence spectra, and fluorescence quantum yield of DPNP have been investigated comprehensively. Significant red shift was observed in the emission spectrum of DPNP compared to the absorption spectrum upon increasing the solvent polarity, indicating a higher dipole moment in the excited state than in the ground state. The difference between the excited and ground state dipole moments (Δµ) were obtained from Lippert-Mataga and Reichardts correlations by means of solvatochromic shift method. The effects of medium acidity on the electronic absorption and emission spectra of DPNP were studied. The interaction of DPNP with colloidal silver nanoparticles (AgNPs) was also studied in ethanol and ethylene glycol using steady state fluorescence quenching measurements. The fluorescence quenching data reveal that dynamic quenching and energy transfer play a major role in the fluorescence quenching of DPNP by Ag NPs.

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