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1.
J Egypt Natl Canc Inst ; 36(1): 22, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38910202

RESUMO

BACKGROUND: Innovations in cancer treatment have contributed to the improved survival rate of cancer patients. The cancer survival rates have been growing and nearly two third of those survivors have been exposed to clinical radiation during their treatment. The study of long-term radiation effects, especially secondary cancer induction, has become increasingly important. An accurate assessment of out-of-field/peripheral dose (PDs) is necessary to estimate the risk of second cancer after radiotherapy and the damage to the organs at risk surrounding the planning target volume. This study was designed to measure the PDs as a function of dose, distances, and depths from Telecobalt-60 (Co-60) beam in water phantom using thermoluminescent dosimeter-100 (TLD-100). METHODS: The PDs were measured for Co-60 beam at specified depths of 0 cm (surface), 5 cm, 10 cm, and 15 cm outside the radiation beam at distances of 5, 10, and 13 cm away from the radiation field edge using TLD-100 (G1 cards) as detectors. These calibrated cards were placed on the acrylic disc in circular tracks. The radiation dose of 2000 mGy of Co-60 beam was applied inside 10 × 10 cm2 field size at constant source to surface distance (SSD) of 80 cm. RESULTS: The results showed maximum and minimum PDs at surface and 5 cm depth respectively at all distances from the radiation field edge. Dose distributions out of the field edge with respect to distance were isotropic. The decrease in PDs at 5 cm depth was due to dominant forward scattering of Co-60 gamma rays. The increase in PDs beyond 5 cm depth was due to increase in the irradiated volume, increase in penumbra, increase in source to axis distance (SAD), and increase in field size due to inverse square factor. CONCLUSION: It is concluded that the PDs depends upon depth and distance from the radiation field edge. All the measurements show PDs in the homogenous medium (water); therefore, it estimates absorbed dose to the organ at risk (OAR) adjacent to cancer tissues/planning target volume (PTV). It is suggested that PDs can be minimized by using the SAD technique, as this technique controls sources of scattered radiation like inverse square factor and effect of penumbra up-to some extent.


Assuntos
Radioisótopos de Cobalto , Imagens de Fantasmas , Dosagem Radioterapêutica , Dosimetria Termoluminescente , Humanos , Dosimetria Termoluminescente/métodos , Água , Planejamento da Radioterapia Assistida por Computador/métodos , Neoplasias/radioterapia , Doses de Radiação , Órgãos em Risco/efeitos da radiação
2.
Biotechnol Adv ; 74: 108394, 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38857660

RESUMO

Glycosaminoglycans (GAGs) are a family of structurally complex heteropolysaccharides that play pivotal roles in biological functions, including the regulation of cell proliferation, enzyme inhibition, and activation of growth factor receptors. Therefore, the synthesis of GAGs is a hot research topic in drug development. The enzymatic synthesis of GAGs has received widespread attention due to their eco-friendly nature, high regioselectivity, and stereoselectivity. The enhancement of the enzymatic synthesis process is the key to its industrial applications. In this review, we overviewed the construction of more efficient in vitro biomimetic synthesis systems of glycosaminoglycans and presented the different strategies to improve enzyme catalysis, including the combination of chemical and enzymatic methods, solid-phase synthesis, and protein engineering to solve the problems of enzyme stability, separation and purification of the product, preparation of structurally defined sugar chains, etc., and discussed the challenges and opportunities in large-scale green synthesis of GAGs.

3.
Spectrochim Acta A Mol Biomol Spectrosc ; 319: 124551, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-38823246

RESUMO

Relationship between excited state dynamics and nonlinear optical (NLO) parameters is very unique. Herein, three different polyoxometalates (POMs) namely WD-POM (Wells-Dawson POM) based porphyrin hybrids WDPOM3PyP, Trans-2WDPOM2PyP, and 3WDPOMPyP (having one, two, and three WD-POM respectively), and their porphyrin precursors with (Trishydroxyl amino methane) namely Tris3PyP, Trans-2Tris2PyP, and 3TrisPyP respectively have been used for the study. Fluorescence decay and Z-scan studies by using nanosecond (ns) time span conveys the corresponding lifespan for each excited state, along with the NLO analysis respectively. The calculated lifetime data were found in the range of 3WDPOMPyP (τ1 = 5.65 ns), Trans-2WDPOM2PyP (τ1 = 2.21 ns), and WDPOM3PyP (τ1 = 1.96 ns). Third order NLO measurements represented that WDPOM3PyP showed better NLO response (χ3 = 2.26 × 10-10esu and ß = 1.54 × 10-5 esu) as compared to Trans-2WDPOM2PyP (χ3 = 1.73 × 10-10 esu and ß = 1.53 × 10-5 esu), and 3WDPOMPyP (χ3 = 1.55 × 10-10 esu and ß = 0.65 × 10-5 esu) obtained at wavelength of 532 nm. Electrochemical studies have shown that the minor energy differences between the singlet and triplet excited states are responsible for intercrossing system (ISC) that helps in the transfer of electrons from porphyrin moiety to WD-POM. By absorbing a photon, the excited species were produced causing an initial charge transfer. This charge transfer state undergoes an electron transfer decaying to the lowest triplet state, and singlet state causing an increase in NLO. The obtained results indicated potential uses in photonic and all-optical switching devices.

4.
Cureus ; 16(5): e61062, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38915994

RESUMO

We report the case of a 23-year-old male presenting with right testicular swelling, post-coital pain, and fever. Initial MRI and local examination suggested testicular carcinoma. Elevated serum alpha-fetoprotein (AFP) and lactate dehydrogenase (LDH) levels were observed. Biopsy confirmed a mixed germ cell tumor (MGCT). Concurrently, the patient was diagnosed with an infection and treated with antibiotics. Remarkably, following antibiotic therapy, fever resolved, and tumor marker levels significantly decreased. Subsequent orchidectomy confirmed the diagnosis of MGCT. This case underscores the importance of recognizing and treating concurrent infections, which may influence both clinical presentation and tumor marker levels in testicular germ cell tumors.

5.
Comput Biol Med ; 177: 108662, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38820780

RESUMO

Total knee arthroplasty (TKA) is a surgical procedure to treat severe knee osteoarthritis. Among several techniques available for performing TKA, imageless TKA is known for achieving precise alignment while minimizing invasiveness. This work proposes a comprehensive algorithm for imageless TKA device to calculate the varus/valgus and flexion/extension angles, as well as resection depths for cutting planes at distal femur and proximal tibia. Moreover, the algorithm calculates the hip-knee-ankle (HKA) and flexion angles of the leg. Initially, the proposed algorithm was validated in a virtual environment using a CT-scanned bone model in Solidworks. Subsequently, for the real-world validation, a SoftBone model was resected with conventional intra and extramedullary rods and cross-checked with the proposed algorithm. For the third validation, another SoftBone model was resected with the proposed algorithm and cuts were measured with a vernier caliper. During this experiment, there was an error of approximately 1 mm for both femoral and tibial resection cases when using an infrared camera with an accuracy of ±0.5 mm. However, this error could be reduced using an infrared camera with higher accuracy.


Assuntos
Algoritmos , Artroplastia do Joelho , Humanos , Artroplastia do Joelho/métodos , Fêmur/cirurgia , Fêmur/diagnóstico por imagem , Tíbia/cirurgia , Tíbia/diagnóstico por imagem , Cirurgia Assistida por Computador/métodos , Articulação do Joelho/cirurgia , Articulação do Joelho/diagnóstico por imagem
6.
Environ Sci Pollut Res Int ; 31(24): 36052-36063, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38744768

RESUMO

Industrialization and the ever-increasing world population have diminished high-quality water resources for sustainable agriculture. It is imperative to effectively treat industrial effluent to render the treated water available for crop cultivation. This study aimed to assess the effectiveness of textile effluent treated with Trametes pubescens MB 89 in supporting maize cultivation. The fungal treatment reduced the amounts of Co, Pb and As in the textile effluent. The biological oxygen demand, total dissolved solids and total suspended solids were within the permissible limits in the treated effluent. The data indicated that the irrigation of maize with fungal-treated textile effluent improved the growth parameters of the plant including root, shoot length, leaf area and chlorophyll content. Moreover, better antioxidant activity, total phenol content and protein content in roots, stems and leaves of maize plants were obtained. Photosynthetic parameters (potential quantum yield, electron transport rate and fluorescence yield of non-photochemical losses other than heat) were also improved in the plants irrigated with treated effluent as compared to the control groups. In conclusion, the treatment of textile effluent with the immobilized T. pubescens presents a sustainable solution to minimize chemical pollution and effectively utilize water resources.


Assuntos
Têxteis , Trametes , Trametes/metabolismo , Zea mays , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água , Águas Residuárias/química
7.
Biopolymers ; : e23586, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38747448

RESUMO

Cellulose nanofibers, a sustainable and promising material with widespread applications, exhibit appreciable strength and excellent mechanical and physicochemical properties. The preparation of cellulosic nanofibers from food or agricultural residue is not sustainable. Therefore, this study was designed to use three halophytic plants (Cressa cretica, Phragmites karka, and Suaeda fruticosa) to extract cellulose for the subsequent conversion to cellulosic nanofibers composites. The other extracted biomass components including lignin, hemicellulose, and pectin were also utilized to obtain industrially valuable enzymes. The maximum pectinase (31.56 IU mL-1), xylanase (35.21 IU mL-1), and laccase (15.89 IU mL-1) were produced after the fermentation of extracted pectin, hemicellulose, and lignin from S. fruticosa, P. karka, and C. cretica, respectively. Cellulose was methylated (with a degree of substitution of 2.4) and subsequently converted into a composite using polyvinyl alcohol. Scanning electron microscopy and Fourier-transform infrared spectroscopy confirmed the successful synthesis of the composites. The composites made up of cellulose from C. cretica and S. fruticosa had a high tensile strength (21.5 and 15.2 MPa) and low biodegradability (47.58% and 44.56%, respectively) after dumping for 3 months in soil, as compared with the composite from P. karka (98.79% biodegradability and 4.9 MPa tensile strength). Moreover, all the composites exhibited antibacterial activity against gram-negative bacteria (Escherichia coli and Klebsiella pneumoniae) and gram-positive bacteria (Staphylococcus aureus). Hence, this study emphasizes the possibility for various industrial applications of biomass from halophytic plants.

8.
Front Microbiol ; 15: 1378834, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38784807

RESUMO

The cultivation system requires that the approach providing biomass for all types of metabolic analysis is of excellent quality and reliability. This study was conducted to enhance the efficiency and yield of antifungal substance (AFS) production in Streptomyces yanglinensis 3-10 by optimizing operation conditions of aeration, agitation, carbon source, and incubation time in a fermenter. Dissolved oxygen (DO) and pH were found to play significant roles in AFS production. The optimum pH for the production of AFS in S. yanglinensis 3-10 was found to be 6.5. As the AFS synthesis is generally thought to be an aerobic process, DO plays a significant role. The synthesis of bioactive compounds can vary depending on how DO affects growth rate. This study validates that the high growth rate and antifungal activity required a minimum DO concentration of approximately 20% saturation. The DO supply in a fermenter can be raised once agitation and aeration have been adjusted. Consequently, DO can stimulate the development of bacteria and enzyme production. A large shearing effect could result from the extreme agitation, harming the cell and deactivating its products. The highest inhibition zone diameter (IZD) was obtained with 3% starch, making starch a more efficient carbon source than glucose. Temperature is another important factor affecting AFS production. The needed fermentation time would increase and AFS production would be reduced by the too-low operating temperature. Furthermore, large-scale fermenters are challenging to manage at temperatures that are far below from room temperature. According to this research, 28°C is the ideal temperature for the fermentation of S. yanglinensis 3-10. The current study deals with the optimization of submerged batch fermentation involving the modification of operation conditions to effectively enhance the efficiency and yield of AFS production in S. yanglinensis 3-10.

10.
Artigo em Inglês | MEDLINE | ID: mdl-38627901

RESUMO

Further development in the area of medicinal chemistry requires facile and atom-economical C-N bond formation from readily accessible precursors using recyclable and reusable catalysts with low process toxicity. In this work, direct N-alkylation of amines with alcohols is performed with a series of Ir-phosphine-functionalized metal-organic framework (MOF) heterogeneous catalysts. The grafted monophosphine-Ir complexes were studied comprehensively to illustrate the ligand-dependent reactivity. The afforded MOF catalysts exhibited high reactivity and selectivity toward N-alkylamine product formation, especially UiO-66-PPh2-Ir, which showed 90% conversion after recycling with no catalyst residue remaining in the product after the reaction. Furthermore, analyses of the active catalyst, mechanistic studies, control experiments, and H2 adsorption tests are consistent with the conclusion that immobilization of the iridium complex on the MOF support enables the formation of the iridium-monophosphine complex and enhances its stability during the reaction. To illustrate the potential of the catalyst for application in medicinal chemistry, two pharmaceutical precursors were synthesized with up to 99% conversion and selectivity.

11.
Front Microbiol ; 15: 1344831, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38585697

RESUMO

Rice serves as a staple food across various continents worldwide. The rice plant faces significant threats from a range of fungal, bacterial, and viral pathogens. Among these, rice false smut disease (RFS) caused by Villosiclava virens is one of the devastating diseases in rice fields. This disease is widespread in major rice-growing regions such as China, Pakistan, Bangladesh, India, and others, leading to significant losses in rice plantations. Various toxins are produced during the infection of this disease in rice plants, impacting the fertilization process as well. This review paper lightens the disease cycle, plant immunity, and infection process during RFS. Mycotoxin production in RFS affects rice plants in multiple ways, although the exact phenomena are still unknown.

12.
Cureus ; 16(3): e57202, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38681470

RESUMO

Electrical storm is a cardiac emergency, defined as three or more hemodynamically unstable ventricular tachyarrythmias within 24 hours or ventricular tachycardia reoccurring within five minutes. The trigger for an electrical storm can be reversible like drug toxicity and electrolyte imbalances or can be irreversible like structural heart disease. Symptomatic patients can have chest pain, palpitations or syncopal episodes. We present a case of a gentleman in his 60s who was diagnosed with electrical storm which started as an out-of-hospital cardiac arrest. Uniqueness in the case lies in the unknown aetiology after all the investigations came back as normal and management of such cases is based on pacemakers and use of antiarrythmic agents to control and prevent further attacks.

13.
J Biotechnol ; 389: 68-77, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38663518

RESUMO

Sustainable farming on ever-shrinking agricultural land and declining water resources for the growing human population is one of the greatest environmental and food security challenges of the 21st century. Conventional, age-old organic farming practices alone, and foods based on costly cellular agriculture, do not have the potential to be upscaled to meet the food supply challenges for feeding large populations. Additionally, agricultural practices relying on chemical inputs have a well-documented detrimental impact on human health and the environment. As the available farming methods have reached their productivity limits, new approaches to agriculture, combining friendly, age-old farming practices with modern technologies that exclude chemical interventions, are necessary to address the food production challenges. Growing genetically modified (GM) crops without chemical inputs can allow agricultural intensification with reduced adverse health and environmental impacts. Additionally, integrating high-value pleiotropic genes in their genetic improvement coupled with the use of modern agricultural technologies, like robotics and artificial intelligence (AI), will further improve productivity. Such 'organic-GM' crops will offer consumers healthy, agrochemical-free GM produce. We believe these agricultural practices will lead to the beginning of a potentially new chemical-free GM agricultural revolution in the era of Agriculture 4.0 and help meet the targets of the United Nations Sustainable Development Goals (SDGs). Furthermore, given the advancement in the genome editing (GE) toolbox, we ought to develop a new category of 'trait-reversible GM crops' to avert the fears of those who believe in ecological damage by GM crops. Thus, in this article, we advocate farming with no or minimal chemical use by combining chemical-free organic farming with the existing biofortified and multiple stress tolerant GM crops, while focusing on the development of novel 'biofertilizer-responsive GE crops' and 'trait-reversible GE crops' for the future.


Assuntos
Produtos Agrícolas , Edição de Genes , Plantas Geneticamente Modificadas , Desenvolvimento Sustentável , Nações Unidas , Produtos Agrícolas/genética , Produtos Agrícolas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/genética , Edição de Genes/métodos , Humanos , Agricultura/métodos
14.
Microsc Res Tech ; 87(8): 1965-1973, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38590279

RESUMO

This study displays the effect of reduced graphene oxide (rGO) nanofiller and polystyrene-b-poly(ethylene-ran-butylene)-b-polystyrene-grafted maleic anhydride (SEBS-g-MA) on the optical, thermal, and mechanical features of expanded polystyrene (EPS). First, the thin films of pristine EPS and composites were prepared using solution cast method. The prepared films were subjected to fourier-transform infrared (FTIR), SEM, UV-visible spectrophotometer, thermogravimetric analysis/differential scanning calorimetry, and universal testing machine for structural, morphological, optical, thermal, and mechanical characterizations. Optical study revealed a significant increase in refractive index and absorption of composites than EPS. Indirect band-gap energy of EPS (~4.08 eV) was reduced to ~1.61 eV for rGO composite and ~ 2.23 eV for composite composed of rGO and SEBS-g-MA. Thermal analyses presented improvement in characterization temperatures such as T10, T50, Tp, Tm, and Tg of composites, which ultimately lead to the thermal stability of prepared composites than pristine EPS. Stress-strain curves displayed higher yield strength (46.62 MPa), Young's modulus (96.29 MPa), and strain at break (0.54%) for EPS+rGO composite than pure EPS having stress at break (1.01 MPa), Young's modulus (12.44 MPa), and strain at break (0.08%). Moreover, ductility with relatively higher strain at break (0.61%) and lower Young's modulus (79.32 MPa) and yield strength (32.98 MPa) was noticed in EPS+rGO+SEBS-g-MA composite than EPS+rGO composite film. Morphological analysis revealed a change in globular morphology of EPS and inhomogeneous dispersion of rGO in EPS to homogeneously dispersed rGO in EPS matrix without globules owing to the addition of SEBS-g-MA. The increase in compatibility of EPS and rGO due to SEBS-g-MA was also observed in FTIR spectra. RESEARCH HIGHLIGHTS: Here, the solution casting approach was used to create the composite film of EPS and rGO with globules of various sizes. After adding SEBS-g-MA, the shape altered to globular free films exhibiting homogenous dispersion of rGO in EPS matrix. An optical investigation showed that composite materials had a significantly higher refractive index and absorption than EPS. The optical, thermal, and mechanical investigations suggest that the produced composites may be a great substitute for virgin EPS, allowing for a wider range of applications.

15.
Arch Microbiol ; 206(4): 149, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38466437

RESUMO

Domestic yak (Bos grunniens) is an economically important feature of the mountainous region of Gilgit-Baltistan in Pakistan where agriculture is restricted and yaks play multiple roles which includes being a source of milk, meat, hides, fuel and power. However little is known about the parasitic infections in Pakistani yaks. Aim of this research was to report the prevalence and genetic diversity of protozoa parasite (Theileria ovis, 18 S rDNA gene was targeted) and an obligate bacterium (Anaplasma marginale, msp-1 gene was amplified) in the blood that was sampled from 202 yaks collected from four districts in Gilgit-Baltistan during January 2023 till January 2024. Results revealed that 6/202 (3%) yaks were of Theileria ovis while 8/202 (4%) were Anaplasma marginale infected. Positive PCR products of both parasites were confirmed by DNA sequencing and their similarity with previously available pathogen sequences was determined by BLAST analysis. Phylogenetic tree indicated that isolates of both parasites displayed genetic. Anaplasma marginale infection varied with the sampling districts and Shigar district had the highest rate of bacterial infection. Cows were significantly more prone to Theileria ovis infection than bulls. Calf and hybrid yaks were more prone to Anaplasma marginale infection. In conclusion, this is the first report that yaks residing the Gilgit-Baltistan region in Pakistan are infected with Theileria ovis and Anaplasma marginale. Similar larger scales studies are recommended in various regions of Gilgit-Baltistan to document the infection rates of these parasites to formulate strategies that will lead to the effective control of these pathogens.


Assuntos
Anaplasma marginale , Anaplasmose , Theileria , Carrapatos , Feminino , Bovinos , Animais , Ovinos , Anaplasma marginale/genética , Theileria/genética , Paquistão/epidemiologia , Anaplasma/genética , Prevalência , Carrapatos/microbiologia , Carrapatos/parasitologia , Filogenia , Anaplasmose/epidemiologia , Anaplasmose/microbiologia
16.
J Infect Dev Ctries ; 18(2): 227-234, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38484341

RESUMO

INTRODUCTION: Extensively drug resistant (XDR) strains of the Salmonella lineages have been reported to spread from Africa to South Asia. XDR strains are resistant to fluoroquinolones, chloramphenicol, co-trimoxazole, and ampicillin, resulting in treatment failure. The objectives of this study included the investigation of transmission of S. Typhi lineages and the identification of the potentially contaminated sources of the XDR typhoid outbreak from different urban areas by using molecular techniques. METHODOLOGY: Environmental samples, including food samples, were collected from different towns and the susceptibility of each isolate to the antimicrobial agents was examined. Molecular identification of different Salmonella lineages including S. Typhi, S. Paratyphi A, H58, and XDR was carried out through multiplex PCR. RESULTS AND CONCLUSIONS: A total of 328 environmental samples including raw vegetables, water, and bakery items were collected. More than half of the tested samples (64%) found harboring Salmonella spp. The Salmonella was confirmed through PCR amplification of species-specific markers that showed the presence of S. Typhi (40%), S. Paratyphi A (8%), H58 (7%), and XDR S. Typhi (6%). Raw vegetables had the highest number of Salmonella spp., indicating consumption of raw vegetables as a possible source of salmonellosis. XDR status was also affirmed through phenotypic antimicrobial susceptibility testing.


Assuntos
Salmonella typhi , Febre Tifoide , Verduras , Febre Tifoide/epidemiologia , Febre Tifoide/tratamento farmacológico , Ampicilina/uso terapêutico , Cloranfenicol/uso terapêutico , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Farmacorresistência Bacteriana
17.
Viruses ; 16(3)2024 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-38543838

RESUMO

The SARS-CoV-2 Omicron sub-variants BA.2.86 and JN.1 contain multiple mutations in the spike protein that were not present in previous variants of concern and Omicron sub-variants. Preliminary research suggests that these variants reduce the neutralizing capability of antibodies induced by vaccines, which is particularly significant for JN.1. This raises concern as many widely deployed COVID-19 vaccines are based on the spike protein of the ancestral Wuhan strain of SARS-CoV-2. While T cell responses have been shown to be robust against previous SARS-CoV-2 variants, less is known about the impact of mutations in BA.2.86 and JN.1 on T cell responses. We evaluate the effect of mutations specific to BA.2.86 and JN.1 on experimentally determined T cell epitopes derived from the spike protein of the ancestral Wuhan strain and the spike protein of the XBB.1.5 strain that has been recommended as a booster vaccine. Our data suggest that BA.2.86 and JN.1 affect numerous T cell epitopes in spike compared to previous variants; however, the widespread loss of T cell recognition against these variants is unlikely.


Assuntos
COVID-19 , Vacinas , Humanos , Vacinas contra COVID-19 , Epitopos de Linfócito T/genética , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/genética , COVID-19/prevenção & controle , Linfócitos T , Anticorpos Neutralizantes , Anticorpos Antivirais
19.
Environ Sci Pollut Res Int ; 31(17): 25486-25499, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38472570

RESUMO

Human biomonitoring of toxic trace elements is of critical importance for public health protection. The current study aims to assess the levels of selected trace metals (Cd, Co, Cr, Cu, Mn, Ni, Pb, and Zn) into paired human nail and hair samples (n = 180 each) from different altitudinal setting along the Indus River, and which were measured by using inductively coupled plasma mass spectrometry (ICP-MS). The human samples (hair and nail) were collected from four different ecological zones of Pakistan which include frozen mountain zone (FMZ), wet mountain zone (WMZ), riverine delta zone (RDZ), and low-lying southern areas (LLZ). Our results showed the following occurrence trends into studied hair samples: higher values (ppm) of Zn (281), Co (0.136), and Mn (5.65) at FMZ; Cr (1.37), Mn (7.83), and Ni (1.22) at WMZ; Co (0.15), Mn (11.89), and Ni (0.99) at RDZ; and Mn (8.99) and Ni (0.90) at LLZ. While in the case of nails, the levels (ppm) of Mn (9.91) at FMZ and Mn (9.38, 24.1, and 12.5), Cr (1.84, 3.87, and 2.33), and Ni (10.69, 8.89, and 12.6) at WMZ, RDZ and LLZ, respectively, showed higher concentration. In general, among the studied trace elements, Mn and Ni in hair/nail samples were consistently higher and exceeded the WHO threshold/published reference values in most of the studied samples (> 50-60%) throughout the Indus basin. Similarly, hair/nail Pb values were also higher in few cases (2-10%) at all studied zones and exceeded the WHO threshold/published reference values. Our area-wise comparisons of studied metals exhibited altitudinal trends for Cd, Cr, Zn, and Mn (p < 0.05), and surprisingly, the values were increasing from south to north (at higher altitudes) and indicative of geogenic sources of the studied toxic elements, except Mn, which was higher at lower floodplain areas. Estimated daily intake (EDI) values showed that food and drinking water had the highest contribution towards Zn, Cu, Mn, and Ni and accumulation at all studied zones. Whereas, dust also acts as the main exposure route for Mn, Co, Cr, and Cd followed by the food, and water.


Assuntos
Água Potável , Metais Pesados , Oligoelementos , Humanos , Monitoramento Ambiental/métodos , Monitoramento Biológico , Cádmio/análise , Paquistão , Chumbo/análise , Oligoelementos/análise , Água Potável/análise , Metais Pesados/análise
20.
Beilstein J Nanotechnol ; 15: 310-316, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38505812

RESUMO

The structural and electronic properties of zinc clusters (Znn) for a size range of n = 2-15 are studied using density functional theory. The particle swarm optimization algorithm is employed to search the structure and to determine the ground-state structure of the neutral Zn clusters. The structural motifs are optimized using the density functional theory approach to ensure that the structures are fully relaxed. Results are compared with the literature to validate the accuracy of the prediction method. The binding energy per cluster is obtained and compared with the reported literature to study the stability of these structures. We further assess the electronic properties, including the ionization potential, using the all-electron FHI-aims code employing G0W0 calculations, and the G0W0Г0(1) correction for a few smaller clusters, which provides a better estimation of the ionization potential compared to other methods.

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