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1.
Ecotoxicol Environ Saf ; 281: 116620, 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38905935

RESUMEN

Iron-nanoparticles (Fe-NPs) are increasingly been utilized in environmental applications due to their efficacy and strong catalytic activities. The novelty of nanoparticle science had attracted many researchers and especially for their green synthesis, which can effectively reuse biological resources during the polymerization reactions. Thus, the synthesis of Fe-NPs utilizing plant extracts could be considered as the eco-friendly, simple, rapid, energy-efficient, sustainable, and cost-effective. The green synthesis route can be recognized as a practical, valuable, and economically effective alternative for large-scale production. During the production process, some biomolecules present in the extracts undergo metal salts reduction, which can serve as both a capping and reducing mechanism, enhancing the reactivity and stability of green-synthesized Fe-NPs. The diversity of species provided a wide range of potential sources for green synthesis of Fe-NPs. With improved understanding of the specific biomolecules involved in the bioreduction and stabilization processes, it will become easier to identify and utilize new, potential plant materials for Fe-NPs synthesis. Newly synthesized Fe-NPs require different characterization techniques such as transmission electron microscope, ultraviolet-visible spectrophotometry, and X-ray absorption fine structure, etc, for the determination of size, composition, and structure. This review described and assessed the recent advancements in understanding green-synthesized Fe-NPs derived from plant-based material. Detailed information on various plant materials suitable of yielding valuable biomolecules with potential diverse applications in environmental safety. Additionally, this review examined the characterization techniques employed to analyze Fe-NPs, their stability, accumulation, mobility, and fate in the environment. Holistically, the review assessed the applications of Fe-NPs in remediating wastewaters, organic residues, and inorganic contaminants. The toxicity of Fe-NPs was also addressed; emphasizing the need to refine the synthesis of green Fe-NPs to ensure safety and environmental friendliness. Moving forward, the future challenges and opportunities associated with the green synthesis of Fe-NPs would motivate novel research about nanoparticles in new directions.

2.
Int J Phytoremediation ; : 1-15, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38755758

RESUMEN

Pakistan is an agricultural country producing plenty of fruits, like: mango, banana, apple, peaches, grapes, plums, variety of citrus fruits including lemon, grapefruit, and oranges. So far the peels of most of the fruits are usually wasted and not properly utilized anywhere. In this work, the peels of banana and grapefruit are converted into biochar by slow pyrolysis under controlled supply of air and used for sequestering cyanide ions from aqueous medium after chemical modification with ZnCl2 and sodium dodecyl sulfate (SDS). The modified biochar was characterized by various instrumental techniques, like: SEM, FTIR, TGA, and CHNS. Different parameters, like: time, temperature, pH, and dose of adsorbent affecting the adsorption of cyanide ions, onto prepared biochar were optimized and to understand the adsorption phenomenon, kinetic and thermodynamic studies were performed. Concentration of cyanide ions was estimated by employing standard ion selective electrode system and it is found that Sodium Dodecyl Sulfate treated biochar of banana peels shown more adsorption capacity, i.e.,: 17.080 mg/g as compared to all samples. Present work revealed that the biochar produced from the fruit waste has sufficient potential to eliminate trace quantities of cyanide from water, especially after treatment with sodium dodecyl sulfate.


An industrial area in Asian and African countries where mining is done using traditional techniques is the major cause of cyanide toxicity in wastewater streams. So, here chemically fabricated biochar made by peels of banana and grape fruit is employed for removal of cyanide ion for controlling aquatic pollution using local resources in green way. Favorable results indicated the feasibility of this process, which is cost effective, convenient, ecofriendly, and sustainable.

3.
Calcif Tissue Int ; 103(3): 353-358, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29572562

RESUMEN

Osteogenesis imperfecta (OI) is a skeletal dysplasia characterized by brittle bones and extraskeletal manifestations. The disease phenotype varies greatly. Most commonly, OI arises from monoallelic mutations in one of the two genes encoding type I collagen, COL1A1 and COL1A2 and is inherited as an autosomal dominant trait. Here, we describe a consanguineous family with autosomal recessive OI caused by a novel homozygous glycine substitution in COL1A2, NM_000089.3: c.604G>A, p.(Gly202Ser), detected by whole-genome sequencing. The index patient is a 31-year-old Greek woman with severe skeletal fragility. She had mild short stature, low bone mineral density of the lumbar spine and blue sclerae. She had sustained multiple long bone and vertebral fractures since childhood and had been treated with bisphosphonates for several years. She also had an affected sister with similar clinical manifestations. Interestingly, the parents and one sister, all carriers of the COL1A2 glycine mutation, did not have manifestations of OI. In summary, we report on autosomal recessive OI caused by a homozygous glycine-to-serine substitution in COL1A2, leading to severe skeletal fragility. The mutation carriers lacked OI manifestations. This family further expands the complex genetic spectrum of OI and underscores the importance of genetic evaluation for correct genetic counselling.


Asunto(s)
Colágeno Tipo I/genética , Osteogénesis Imperfecta/genética , Adulto , Femenino , Homocigoto , Humanos , Masculino , Linaje , Mutación Puntual
4.
Microb Pathog ; 103: 8-12, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27956216

RESUMEN

Extended-spectrum-lactamases (ESBLs) of the CTX-M type is worrisome issue in many countries of the world from past decade. But little is known about CTX-M beta-lactamase producing bacteria in Pakistan. Therefore, this study was carried out to investigate the distribution of CTX-M beta-lactamase producing E. coli and Klebsiella pneumoniae using phenotypic and molecular techniques. A total of 638 E. coli and 338 Klebsiella pneumoniae were isolated from patients attending two hospitals and one diagnostic Centre in Pakistan during 2013-2015. ESBL production was screened by double disc synergism, combination disc (cefotaxime and ceftazidime with clavulanic acid) and E-test. These strains were further characterized by PCR (CTX-M I, CTX-M III) and sequencing. After ribotyping of strains accession numbers were obtained. These isolates were highly resistant to cephalosporins, ceftazidime, cefotaxime, aztreonam, and cefuroxime but susceptible to carbapenems, sulfzone, amikacin and tazocin. Multiple antibiotic resistances index (MAR) revealed that 51% of E. coli strains fell in the range of 0.61-0.7 and 39% of Klebsiella pneumoniae strains fell in the range of 0.71-0.8. 64% Double disc synergism (DDS), 76.4% combination disc (CD), 74% E-test showed ESBL positivity in strains. In E. coli ESBL genes blaCTX-M-I and blaCTX-M-III were detected in 212 (72.1%) and 25 (8.5%) respectively. In Klebsiella pneumoniae ESBL genes blaCTX-M-I and blaCTX-M-III were detected in 89 (82.4%) and 10 (9.2%). Combination of both genes blaCTX-M-I and blaCTX-M-III were found in 16 (5.4%) of E. coli strains and 5 (4.6%) of Klebsiella pneumoniae strains. Sequencing revealed that CTXM-15 was predominately present in the CTX-M-I group. The prevalence of ESBL producing E. coli and Klebsiella pneumoniae isolates was high and the majority of them positive for blaCTX-M-I as compared to blaCTX-M-III. These findings highlight the need to further investigate the epidemiology of other CTX-M beta-lactamases in Pakistan.


Asunto(s)
Infecciones por Escherichia coli/epidemiología , Infecciones por Escherichia coli/microbiología , Escherichia coli/genética , Infecciones por Klebsiella/epidemiología , Infecciones por Klebsiella/microbiología , Klebsiella pneumoniae/genética , beta-Lactamasas/genética , Adulto , Antibacterianos/farmacología , Farmacorresistencia Bacteriana , Escherichia coli/clasificación , Escherichia coli/efectos de los fármacos , Proteínas de Escherichia coli/biosíntesis , Proteínas de Escherichia coli/genética , Femenino , Humanos , Klebsiella pneumoniae/clasificación , Klebsiella pneumoniae/efectos de los fármacos , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Pakistán/epidemiología , Fenotipo , beta-Lactamasas/biosíntesis
5.
J Ayub Med Coll Abbottabad ; 26(2): 255-7, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25603690
6.
Cureus ; 16(1): e53051, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38410301

RESUMEN

Objective The study aims to evaluate the effectiveness of a professionalism program by conducting focus group discussions (FGDs). The research focuses on understanding how the program influences the development of professionalism skills among medical students, as well as their perceptions and experiences regarding the program. The study's objectives revolve around identifying the strengths and weaknesses of the program from the perspective of the students. Methods This was a qualitative study done after obtaining approval from the Institutional Review Committee, Islamic International Medical College. Students of 4th year Bachelor of Medicine and Bachelor of Surgery (MBBS; 56 students) were selected for the study. A convenience sampling technique was used to select the participants for FGDs. Seven separate FGDs were conducted, with eight participants in each group. All the FGDs were audiotaped. Data were transcribed and translated. Data were analyzed using the thematic analysis on Atlas. Both obvious and hidden content were analyzed. Codes and themes were identified, which were then finalized with consensus. Codes were then categorized into sub-themes, and finally, themes were generated. Results Participants identified the problems associated with applying professionalism during FGDs. These challenges encompassed hefty workloads and a perceived disparity between theoretical knowledge and practical implementation. The students highlighted the importance of practical teaching methods, the cultivation of role models, the alignment of curriculum with real-world experiences, and the revision of assessment methods. This study analyzes the obstacles and potential advantages associated with professionalism education and presents significant perspectives on improving it for upcoming healthcare practitioners. Conclusion Professionalism is a crucial component, and each graduate of a medical school should be fully qualified as a professional after graduation. As we want our future doctors to be skilled at both professional qualities and diagnosis, it is crucial that medical institutions teach professionalism.

7.
RSC Adv ; 14(10): 7040-7051, 2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38414992

RESUMEN

Gas sensing technology has a broad impact on society, ranging from environmental and industrial safety to healthcare and everyday applications, contributing to a safer, healthier, and more sustainable world. We studied pure and Fe-decorated hexagonal boron nitride (h-BN) gas sensor for monitoring of carbon-based gases using density functional theory (DFT). The calculations utilized the Generalized Gradient Approximation with the Perdew-Burke-Ernzerhof (GGA-PBE) exchange-correlation functional. The novelty of our study lies in the investigation of the adsorption of harmful gases such as carbonyl sulfide, carbinol, carbimide, and carbonyl fluoride on both pure and Fe-decorated h-BN. The deviation in structural, electronic, and adsorption properties of h-BN due to Fe decoration has been studied along with the sensing ability to design said material towards carbon monoxide (CO), carbon dioxide (CO2), carbonyl sulfide (COS), carbinol, (CH4O), carbimide (CH2N2), and carbonyl fluoride (CF2O) gases. Gases such as CO, COS, CH2N2, and CF2O exhibited chemisorption, while CO2, and CH4O exhibited physisorption behavior. The introduction of Fe altered the semiconductor properties of h-BN and rendered it metallic. Enhanced electronic properties were observed due to a robust hybridization occurring between the d-orbitals of Fe-decorated BN and the gas molecules. The extended recovery periods observed for gases, aside from CO2, indicate their adhesive interactions with Fe-decorated h-BN. The reduction in desorption duration as temperature rises allows Fe-decorated h-BN to function as a reversible gas sensor. This research opens up a novel pathway for the synthesis and advancement of cost-effective, environmentally friendly double-atom catalysts with high sensitivity for capturing and detecting molecules such as CO, COS, CH2N2, CO2, CH4O, and CF2O.

8.
Proc (Bayl Univ Med Cent) ; 37(2): 303-311, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38343470

RESUMEN

The aim of this narrative review is to synthesize existing evidence-based knowledge on juvenile idiopathic arthritis-associated uveitis (JIA-U). We highlight epidemiology, pathophysiology, causes and genetics, risk factors, clinical features, diagnosis and screening, laboratory biomarkers, treatment options, trials with recent advances, and research challenges pertaining to JIA-U. The prevalence of JIA-U varies with different JIA subtypes, most frequently associated with the oligoarticular subtype. The risk factors involved in the development of JIA-U include younger age, antinuclear antibody (ANA) positivity, and the oligoarticular subtype of JIA, along with some specific major histocompatibility complex genes. Certain laboratory biomarkers, such as ANA, rheumatoid factor, interferon-λ, erythrocyte sedimentation rate, and transthyretin, have been used in JIA-U diagnosis, progress monitoring, and prognostication. Clinical features of JIA-U can range from asymptomatic to ophthalmic symptoms like redness, blurred vision, decreased visual acuity, hypopyon, and posterior uveitis, which can lead to retinal detachment and macular edema. The management protocol involves topical and systemic steroids, cycloplegics, disease-modifying antirheumatic drugs, biologic drugs, and surgical options. Early detection combined with prompt treatment is crucial to preventing irreversible vision loss in JIA-U.

9.
Front Plant Sci ; 14: 932923, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36909407

RESUMEN

Crop plants are vulnerable to various biotic and abiotic stresses, whereas plants tend to retain their physiological mechanisms by evolving cellular regulation. To mitigate the adverse effects of abiotic stresses, many defense mechanisms are induced in plants. One of these mechanisms is the mitogen-activated protein kinase (MAPK) cascade, a signaling pathway used in the transduction of extracellular stimuli into intercellular responses. This stress signaling pathway is activated by a series of responses involving MAPKKKs→MAPKKs→MAPKs, consisting of interacting proteins, and their functions depend on the collaboration and activation of one another by phosphorylation. These proteins are key regulators of MAPK in various crop plants under abiotic stress conditions and also related to hormonal responses. It is revealed that in response to stress signaling, MAPKs are characterized as multigenic families and elaborate the specific stimuli transformation as well as the antioxidant regulation system. This pathway is directed by the framework of proteins and stopping domains confer the related associates with unique structure and functions. Early studies of plant MAPKs focused on their functions in model plants. Based on the results of whole-genome sequencing, many MAPKs have been identified in plants, such as Arbodiposis, tomato, potato, alfalfa, poplar, rice, wheat, maize, and apple. In this review, we summarized the recent work on MAPK response to abiotic stress and the classification of MAPK cascade in crop plants. Moreover, we highlighted the modern research methodologies such as transcriptomics, proteomics, CRISPR/Cas technology, and epigenetic studies, which proposed, identified, and characterized the novel genes associated with MAPKs and their role in plants under abiotic stress conditions. In-silico-based identification of novel MAPK genes also facilitates future research on MAPK cascade identification and function in crop plants under various stress conditions.

10.
Photochem Photobiol ; 98(5): 1017-1024, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35092012

RESUMEN

Applying sunscreen on human skin provides photoprotection against the harmful ultraviolet (UV) radiation of the sun. Sunscreen absorbs UV radiations and dissipates the absorbed energy through various radiative and nonradiative pathways. The attachment of functionalized quantum dots (QDs) to the sunscreen component is a novel idea to enhance the absorption cross-section of UV radiations. Therefore, the attachment of the sunscreen component to the ligand functionalized biocompatible QDs and the absorbed energy transfer from sunscreen to the QDs could work as a model system to overall improve the efficiency of the sunscreen. This study elucidates the mechanism of size-dependent Förster resonance energy transfer (FRET) efficiency and its rate between 2-phenylbenzimidazole-5-sulfonic acid (PBSA) and mercaptoacetic acid (MAA) functionalized CdS QDs. In the PBSA-QDs dyad, the PBSA (donor) dissipates UV-absorbed energy to the CdS QDs (acceptor). Following excitation at 306 nm, the steady-state photoluminescence (SSPL) and time-resolved photoluminescence (TRPL) techniques measurements demonstrate that both the nonradiative energy transfer efficiency and rate are QDs size-dependent in addition to donor-acceptor distance, and suggest that bigger sized-QDs result in an increase of the FRET efficiency.


Asunto(s)
Puntos Cuánticos , Humanos , Bencimidazoles , Transferencia Resonante de Energía de Fluorescencia/métodos , Ligandos , Ácidos Sulfónicos , Protectores Solares
11.
Front Plant Sci ; 12: 701529, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34539694

RESUMEN

A total of 16 OsS40 genes of Oryza sativa were identified in our previous work, but their functions remain unclear. In this study, 13 OsS40 members were knocked out using the CRISPR/cas9 gene-editing technology. After screening phenotype characterization of CRISPR/Cas9 mutants compared to WT, five oss40s mutants exhibited a stay-green phenotype at 30 days after heading. Moreover, increased grain size and grain weight occurred in the oss40-1, oss40-12, and oss40-14 lines, while declined grain weight appeared in the oss40-7 and oss40-13 mutants. The transcript levels of several senescence-associated genes (SAGs), chlorophyll degradation-related genes (CDGs), as well as WRKY members were differentially decreased in the five stay-green oss40s mutants compared to WT. Five oss40 mutants also exhibited a stay-green phenotype when the detached leaves were incubated under darkness for 4 days. OsSWEET4 and OsSWEET1b were significantly upregulated, while OsSWEET1a and OsSWEET13 were significantly downregulated in both oss40-7 and oss40-14 compared to WT. Furthermore, these five OsS40 displayed strong transcriptional activation activity and were located in the nucleus. Most of the OsS40 genes were downregulated in the oss40-1, oss40-7, and oss40-12 mutants, but upregulated in the oss40-13 and oss40-14 mutants, indicating coordinated regulation among OsS40 members. These results suggest that OsS40-1, OsS40-7, OsS40-12, OsS40-13, and OsS40-14 are senescence-associated genes, involved in the senescence and carbon allocation network by modulating other OsS40 members, SWEET member genes, and senescence-related gene expression.

12.
Materials (Basel) ; 14(12)2021 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-34201266

RESUMEN

Cancer remains a global health burden prompting affordable, target-oriented, and safe chemotherapeutic agents to reduce its incidence rate worldwide. In this study, a rapid, cost-effective, and green synthesis of titanium dioxide (TiO2) nanoparticles (NPs) has been carried out; Ex vivo and in vivoevaluation of their safety and anti-tumor efficacy compared to doxorubicin (DOX), a highly efficient breast anti-cancer agent but limited by severe cardiotoxicity in many patients.Thereby,TiO2 NPs were eco-friendly synthetized using aqueous leaf extract of the tropical medicinal shrub Zanthoxylum armatum as a reducing agent. Butanol was used as a unique template. TiO2 NPs were physically characterized by ultraviolet-visible (UV-Vis) spectroscopy, dynamic light scattering (DLS), transmission electron microscopy (TEM), scanning electron microscope (SEM), X-ray powder diffraction (XRD), and Fourier-transform infrared spectroscopy (FTIR) as routine state-of-the art techniques. The synthesized TiO2 NPs were then evaluated for their cytotoxicity (by MTT, FACS, and oxidative stress assays) in 4T1 breast tumor cells, and their hemocompatibility (by hemolysis assay). In vivo anti-tumor efficacy and safety of the TiO2 NPs were further assessed using subcutaneous 4T1 breast BALB/c mouse tumor model.The greenly prepared TiO2 NPs were small, spherical, and crystalline in nature. Interestingly, they were hemocompatible and elicited a strong DOX-like concentration-dependent cytotoxicity-induced apoptosis both ex vivo and in vivo (with a noticeable tumor volume reduction). The underlying molecular mechanism was, at least partially, mediated through reactive oxygen species (ROS) generation (lipid peroxidation). Unlike DOX (P < 0.05), it is important to mention that no cardiotoxicity or altered body weight were observed in both the TiO2 NPs-treated tumor-bearing mouse group and the PBS-treated mouse group (P > 0.05). Taken together, Z. armatum-derived TiO2 NPs are cost-effective, more efficient, and safer than DOX. The present findings shall prompt clinical trials using green TiO2 NPs, at least as a possible alternative modality to DOX for effective breast cancer therapy.

13.
J Pharm Biomed Anal ; 179: 112917, 2020 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-31767222

RESUMEN

We have developed a fluorescence double-probe detection system with signal amplification for simple typing and determination of single nucleotide polymorphism (SNP) functional gene based on non-sequence dependence of ExoIII nuclease on dsDNA and rapid separation of magnetic bead. Matched detected gene can cyclically release abundant fluorescence-labeled ssDNA from the probe and the corresponding measured fluorescence signal is amplified up to 6063 times. In this case, the probe cannot release the measured fluorescence signal for the point mutation gene and then the corresponding measured signal is inhibited. According to signal amplification and inhabitation of the probe, we proposed both an accurate genotyping approach with strong specificity and a sensitive determination approach with high selectivity for SNP functional gene. For qualitative genotyping, there are obvious genotype-based differences of measured fluorescence phenotypes among three kinds of the samples of the investigated SNP. The quantitative determinations of its wild-type gene and mutant gene have all a good linearity in the range from 0.5 to 500 pmol/L with the correlation coefficients R2 of 0.9940 and 0.9911, and a high sensitivity with the detection limits of 0.11 and 0.20 pmol/L, respectively. Compared to the usual single-probe detection system, the developed double-probe system can achieve not only accurate genotyping but also the sensitive gene determination. Meanwhile, it is also a simple and reliable method for both quantitative and qualitative analysis of functional gene.


Asunto(s)
Exodesoxirribonucleasas/genética , Fluorescencia , Fenómenos Magnéticos , Polimorfismo de Nucleótido Simple/genética , ADN/genética , Sondas de ADN , ADN de Cadena Simple/genética , Genotipo , Humanos , Límite de Detección , Mutación Puntual
14.
Artículo en Inglés | MEDLINE | ID: mdl-29484173

RESUMEN

Background: South-Asia is known as a hub for multidrug-resistant (MDR) bacteria. Unfortunately, proper surveillance and documentation of MDR pathogens is lacking in Pakistan. The alarming increase in the prevalence of extended-spectrum ß-lactamase (ESBL)-producing Enterobacteriaceae is a serious problem. From this perspective, we analysed published data regarding ESBL-producing Enterobacteriaceae in different regions of Pakistan. Methods: A meta-analysis was performed to determine the prevalence of ESBL-producing Enterobacteriaceae in Pakistan. A Web-based search was conducted in electronic databases, including PubMed, Scopus and PakMedi Net (for non-indexed Pakistani journals). Articles published (in either indexed or non-indexed journals) between January 2002 and July 2016 were included in the study. Relevant data were extracted, and statistical analysis was performed using the Metaprop command of STATA version 14.1. Results: A total of 68 studies were identified from the electronic data base search, and 55 of these studies met our inclusion criteria. Pakistan's overall pooled proportion of ESBL-producers was 0.40 (95% CI: 0.34-0.47). The overall heterogeneity was significant (I2 = 99.75%, p < 0.001), and significant ES = 0 (Z = 18.41, p < 0.001) was found. OXA, SHV, TEM and CTX-M were the most commonly found gene variants for ESBLs in these studies. Conclusion: The prevalence of ESBL-producing Enterobacteriaceae is high in Pakistan. Little is known about the annual frequency of ESBLs and their prevalence in different provinces of Pakistan. No data are available regarding ESBL frequency in Baluchistan. This underscores an urgent demand for regular surveillance to address this antimicrobial resistance problem. Surveillance to better understand the annual ESBL burden is crucial to improve national and regional guidelines.


Asunto(s)
Infecciones por Enterobacteriaceae/epidemiología , Enterobacteriaceae/metabolismo , Epidemiología Molecular , beta-Lactamasas/biosíntesis , beta-Lactamasas/genética , Antibacterianos/uso terapéutico , Bases de Datos Factuales , Farmacorresistencia Bacteriana Múltiple , Enterobacteriaceae/enzimología , Enterobacteriaceae/genética , Enterobacteriaceae/patogenicidad , Infecciones por Enterobacteriaceae/microbiología , Heterogeneidad Genética , Humanos , Pakistán/epidemiología , Prevalencia
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