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1.
Heliyon ; 10(8): e29337, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38655346

RESUMO

The prime goal of the present research is to synthesize pristine zinc sulfide (PZS) and cobalt (Co)-doped zinc sulfide (CDZS) thin films with different doping concentrations (DC) via chemical bath deposition (CBD) method. The effect of Co-doping on the surface topography, structural, optical and dc-electrical behaviors of PZS thin films has been ascertained. Scanning electron microscopy images exhibited nearly sphere-shaped agglomerates of grains dispersed throughout the surface with cracks in PZS thin film whereas cracks were absent in CDZS. Atomic force microscopy image displayed smooth surface of CDZS thin film with evenly dispersed small grains. The hexagonal wurtzite structure of PZS and CDZS thin films with varied X-ray diffraction (XRD) parameters was confirmed via XRD analysis. Optical investigation revealed that the optical direct band gap energy increased with decreasing DC from 12 % to 4 %. Alteration of other optical parameters namely absorption coefficient, extinction coefficient, refractive index, real and imaginary parts of dielectric constant, etc. with DC was also discussed. Direct current electrical investigation revealed that the current-voltage characteristics are linear for all thin films signifying that the electrical conduction in CDZS is ohmic in nature.

3.
Cureus ; 15(10): e47489, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38021748

RESUMO

BACKGROUND: Scaphoid fracture is most often missed and mismanaged leading to scaphoid nonunion with or without avascular necrosis. When avascular necrosis of the proximal pole is confirmed with intraoperative evaluation, conventional bone graft is not enough. The treatment modalities are evolving day by day. The current trend is vascular bone grafting, which has shown good outcomes in terms of union and wrist function. METHODS: Fifty patients with nonunion fracture of the scaphoid were treated with vascularized pedicle bone graft from the dorsum of the distal radius using the 1st and 2nd intercompartmental supraretinacular artery, from 2014 to 2022. Preoperative and postoperative clinical evaluation included pain, range of motion, grip strength, and satisfaction. The average follow-up period was 12 months. RESULTS: Among 18 patients, 14 were clinically improved after a mean follow-up period of eight weeks. Thirteen patients reported the absence of any discomfort, three patients reported slight discomfort after hard work, and two patients reported pain with light work. The wrist range of motion improved significantly, and the hand grip strength also improved. According to the modified Mayo wrist scoring chart, clinical results were rated as excellent in 24 cases, good in 19 cases, and poor in four cases. CONCLUSION: 1,2 intercompartmental supraretinacular artery (1,2 ICSRA) is superficial to the extensor retinaculum and is a proper pedicle of vascularized bone graft due to the ease of visibility and dissection. The functional results and union rates were satisfactory in our study.

5.
J Infect ; 84(6): 749-759, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35461908

RESUMO

The prevalence of Carbapenem-resistant Enterobacteriaceae (CRE) has increased dramatically in recent years and has become a global public health issue. Since carbapenems are considered the last drugs of choice, infections caused by these pathogens are difficult to treat and carry a high risk of mortality. Several antibiotic combination regimens have been utilized for the management of CRE infections or to eradicate colonization in CRE carriers with variable clinical responses. In addition, recent studies have explored the use of fecal microbiota transplantation (FMT) to eradicate CRE infections. Here, we conducted a systematic review of publications in which FMT was used to eliminate CRE colonization in infected individuals. We searched the PubMed, Cochrane, and Medline databases up to November 30, 2021. Ten studies (209 patients) met the inclusion criteria for this review with three articles describing retrospective cohorts (n = 53 patients) and seven reporting prospective data (n = 156 patients), including one randomized open-label clinical trial. All studies were published between 2017 and 2021 with eight studies from Europe and two from South Korea. There were substantial variations in terms of outcome measurements and study endpoint among these studies. Among the 112 FMT recipients with confirmed CRE colonization, CRE decolonization was reported in 55/90 cases at one month after FMT and at the end of the study follow-up (6-12 months), decolonization was documented in 74/94 (78.7%) patients. The predominant CRE strains reported were Klebsiella pneumoniae and Escherichia coli and the most frequently documented carbapenemases were KPC, OXA-48, and NDM. In general, FMT was well tolerated, with no severe complications reported even in immunosuppressed patients and in those with multiple underlying conditions. In conclusion, FMT appears to be safe and effective in eradicating CRE colonization, however, more studies, especially randomized trials, are needed to validate the safety and clinical utility of FMT for CRE eradication.


Assuntos
Enterobacteriáceas Resistentes a Carbapenêmicos , Infecções por Enterobacteriaceae , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Portador Sadio , Infecções por Enterobacteriaceae/terapia , Escherichia coli , Transplante de Microbiota Fecal/efeitos adversos , Humanos , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Retrospectivos
6.
Leukemia ; 36(3): 847-855, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34743190

RESUMO

Although a glycosylphosphatidylinositol-anchored protein (GPI-AP) CD109 serves as a TGF-ß co-receptor and inhibits TGF-ß signaling in keratinocytes, the role of CD109 on hematopoietic stem progenitor cells (HSPCs) remains unknown. We studied the effect of CD109 knockout (KO) or knockdown (KD) on TF-1, a myeloid leukemia cell line that expresses CD109, and primary human HSPCs. CD109-KO or KD TF-1 cells underwent erythroid differentiation in the presence of TGF-ß. CD109 was more abundantly expressed in hematopoietic stem cells (HSCs) than in multipotent progenitors and HSPCs of human bone marrow (BM) and cord blood but was not detected in mouse HSCs. Erythroid differentiation was induced by TGF-ß to a greater extent in CD109-KD cord blood or iPS cell-derived megakaryocyte-erythrocyte progenitor cells (MEPs) than in wild-type MEPs. When we analyzed the phenotype of peripheral blood MEPs of patients with paroxysmal nocturnal hemoglobinuria who had both GPI(+) and GPI(-) CD34+ cells, the CD36 expression was more evident in CD109- MEPs than CD109+ MEPs. In summary, CD109 suppresses TGF-ß signaling in HSPCs, and the lack of CD109 may increase the sensitivity of PIGA-mutated HSPCs to TGF-ß, thus leading to the preferential commitment of erythroid progenitor cells to mature red blood cells in immune-mediated BM failure.


Assuntos
Antígenos CD/metabolismo , Células Eritroides/citologia , Células-Tronco Hematopoéticas/citologia , Proteínas de Neoplasias/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Diferenciação Celular , Linhagem Celular , Células Cultivadas , Células Eritroides/metabolismo , Eritropoese , Proteínas Ligadas por GPI/metabolismo , Hematopoese , Células-Tronco Hematopoéticas/metabolismo , Humanos
8.
J Colloid Interface Sci ; 610: 304-312, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34922081

RESUMO

Metal-organic frameworks (MOFs) with exceptional features such as high structural diversity and surface area as well as controlled pore size has been considered a promising candidate for developing room temperature highly-sensitive gas sensors. In comparison, the hetero-metallic MOFs with redox-active open-metal sites and mixed metal nodes may create peculiar surface properties and synergetic effects for enhanced gas sensing performances. In this work, the Fe atoms in the Fe3 (Porous coordination network) PCN-250 MOFs are partially replaced by transition metal Co, Mn, and Zn through a facile hydrothermal approach, leading to the formation of hetero-metallic MOFs (Fe2IIIMII, M = Co, Mn, and Zn). While the PCN-250 framework is maintained, the morphological and electronic band structural properties are manipulated upon the partial metal replacement of Fe. More importantly, the room temperature NO2 sensing performances are significantly varied, in which Fe2Mn PCN-250 demonstrates the largest response magnitude for ppb-level NO2 gas compared to those of pure Fe3 PCN-250 and other hetero-metallic MOF structures mainly attributed to the highest binding energy of NO2 gas. This work demonstrates the strong potential of hetero-metallic MOFs with carefully engineered substituted metal clusters for power-saving and high-performance gas sensing applications.

10.
Respir Med ; 191: 106716, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34923286

RESUMO

The COVID-19 pandemic has put a strain on all the healthcare systems around the world. The World Health Organization (WHO) stated that the "highly mutated" Omicron variant, known as B.1.1.529, could represent a very high global risk of sudden increases in infections. As a result, it is urgently necessary to explore the most suitable treatments for this variant. The purpose of the study was to investigate the currently available studies regarding the Omicron variant and try to identify any potentially effective therapies for the Omicron variant.


Assuntos
COVID-19/virologia , SARS-CoV-2 , Antivirais/uso terapêutico , COVID-19/fisiopatologia , COVID-19/prevenção & controle , COVID-19/transmissão , Vacinas contra COVID-19/uso terapêutico , Glucocorticoides/uso terapêutico , Humanos , Imunização Secundária , Fatores Imunológicos/uso terapêutico
11.
Glob Policy ; 2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36718469

RESUMO

The purpose of this article is to demonstrate how a lack of policy attention has exacerbated the extreme circumstances faced by the Rohingya and how they can contribute to deterioration of their health, livelihood, and education, as well as their repatriation to their homeland. This article is based on data collected from field observations and interviews prior to and during the pandemic. This study confirms that the Rohingya refugee populations endure a higher level of suffering from lack of food security and livelihood, lack of basic amenities and financial resources, and accommodation is overcrowded compared with the pre-pandemic period. The lack of a specific policy for the Rohingya has compounded the current situation in Bangladesh. This research is crucial for countries receiving refugees as well as the countries from which they flee and other actors.

12.
ACS Nano ; 15(10): 16067-16075, 2021 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-34623147

RESUMO

High dielectric constant (high-k) ultrathin films are required as insulating gate materials. The well-known high-k dielectrics, including HfO2, ZrO2, and SrTiO3, feature three-dimensional lattice structures and are thus not easily obtained in the form of distinct ultrathin sheets. Therefore, their deposition as ultrathin layers still imposes challenges for electronic industries. Consequently, new high-k nanomaterials with k in the range of 40 to 100 and a band gap exceeding 4 eV are highly sought after. Antimony oxide nanosheets appear as a potential candidate that could fulfill these characteristics. Here, we report on the stoichiometric cubic polymorph of 2D antimony oxide (Sb2O3) as an ideal high-k dielectric sheet that can be synthesized via a low-temperature, substrate-independent, and silicon-industry-compatible liquid metal synthesis technique. A bismuth-antimony alloy was produced during the growth process. Preferential oxidation caused the surface of the melt to be dominated by α-Sb2O3. This ultrathin α-Sb2O3 was then deposited onto desired surfaces via a liquid metal print transfer. A tunable sheet thickness between ∼1.5 and ∼3 nm was achieved, while the lateral dimensions were within the millimeter range. The obtained α-Sb2O3 exhibited high crystallinity and a wide band gap of ∼4.4 eV. The relative permittivity assessment revealed a maximum k of 84, while a breakdown electric field of ∼10 MV/cm was observed. The isolated 2D α-Sb2O3 nanosheets were utilized in top-gated field-effect transistors that featured low leakage currents, highlighting that the obtained material is a promising gate oxide for conventional and van der Waals heterostructure-based electronics.

14.
Cancer Genomics Proteomics ; 18(5): 661-673, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34479918

RESUMO

BACKGROUND/AIM: Coronavirus disease 2019 (COVID-19) poses a great challenge for the treatment of cancer patients. It presents as a severe respiratory infection in aged individuals, including some lung cancer patients. COVID-19 may be linked to the progression of aggressive lung cancer. In addition, the side effects of chemotherapy, such as chemotherapy resistance and the acceleration of cellular senescence, can worsen COVID-19. Given this situation, we investigated the role of paclitaxel (a chemotherapy drug) in the cell proliferation, apoptosis, and cellular senescence of gefitinib-resistant non-small-cell lung cancer (NSCLC) cells (PC9-MET) to clarify the underlying mechanisms. MATERIALS AND METHODS: PC9-MET cells were treated with paclitaxel for 72 h and then evaluated by a cell viability assay, DAPI staining, Giemsa staining, apoptosis assay, a reactive oxygen species (ROS) assay, SA-ß-Gal staining, a terminal deoxynucleotidyl transferase dUTP nick-end labeling assay and Western blotting. RESULTS: Paclitaxel significantly reduced the viability of PC9-MET cells and induced morphological signs of apoptosis. The apoptotic effects of paclitaxel were observed by increased levels of cleaved caspase-3 (Asp 175), cleaved caspase-9 (Asp 330) and cleaved PARP (Asp 214). In addition, paclitaxel increased ROS production, leading to DNA damage. Inhibition of ROS production by N-acetylcysteine attenuates paclitaxel-induced DNA damage. Importantly, paclitaxel eliminated cellular senescence, as observed by SA-ß-Gal staining. Cellular senescence elimination was associated with p53/p21 and p16/pRb signaling inactivation. CONCLUSION: Paclitaxel may be a promising anticancer drug and offer a new therapeutic strategy for managing gefitinib-resistant NSCLC during the COVID-19 pandemic.


Assuntos
Antineoplásicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Gefitinibe/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Paclitaxel/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Senescência Celular/efeitos dos fármacos , Humanos , Neoplasias Pulmonares/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos
15.
Cancer Genomics Proteomics ; 18(5): 645-659, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34479917

RESUMO

BACKGROUND/AIM: Paclitaxel is used as a first-line and subsequent therapy for the treatment of various cancers. However, the function and mechanisms of action of paclitaxel in non-small-cell lung cancer (NSCLC) remain unknown. In this study, the molecular mechanism underlying the anticancer activity of paclitaxel was investigated in vitro in a human NSCLC cell line carrying the EGFR exon 19 deletion (PC9). MATERIALS AND METHODS: PC9 cells were treated with paclitaxel and then evaluated with a cell viability assay, DAPI staining, Giemsa staining, apoptosis assay, reactive oxygen species (ROS) assay, terminal deoxynucleotidyl transferase dUTP nick-end labeling assay and Western blotting. RESULTS: Paclitaxel markedly decreased the viability of PC9 cells and induced morphological signs of apoptosis. The apoptotic effects of paclitaxel were observed through caspase cascade activation, along with ROS generation and loss of mitochondrial membrane potential (MMP). Furthermore, paclitaxel induced ROS-mediated DNA damage that triggered the activation of the extrinsic pathway of apoptosis via the up-regulation of death receptor (DR5) and caspase-8 activation. In addition, we found that paclitaxel effectively suppressed the EGFR/PI3K/AKT/mTOR signaling pathway to impede PC9 cell growth. Paclitaxel induced cell cycle arrest at the G1 phase in response to DNA damage, in association with the suppression of CDC25A, Cdk2 and Cyclin E1 protein expression. CONCLUSION: Paclitaxel showed anticancer effects against NSCLC by activating extrinsic and intrinsic apoptotic pathways through enhancing ROS generation, inducing cell cycle arrest, and suppressing EGFR/PI3K/AKT/mTOR signaling pathway.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Dano ao DNA/genética , Paclitaxel/uso terapêutico , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Antineoplásicos Fitogênicos/farmacologia , Receptores ErbB/metabolismo , Humanos , Paclitaxel/farmacologia , Espécies Reativas de Oxigênio , Transdução de Sinais
17.
Anticancer Res ; 41(6): 2963-2977, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34083287

RESUMO

BACKGROUND/AIM: Non-small-cell lung cancer (NSCLC) remains a significant cause of death despite the recent introduction of several improved therapeutics. Pemetrexed disodium heptahydrate (pemetrexed) is currently available in combination with a platinum derivative for patients with advanced non-squamous NSCLC for first-line treatment, and as a single agent for second-line treatment. However, the mechanisms underlying its anticancer activities are still not well understood. In this study, we evaluated the growth inhibitory effects of pemetrexed on PC9 (EGFR exon 19 deletion) cells and elucidated the underlying molecular mechanisms. MATERIALS AND METHODS: PC9 cells were treated with pemetrexed and then assessed for the cell viability, morphological and nuclear changes, antigenic alterations, SA-ß-gal staining, and changes in protein expression. RESULTS: Pemetrexed reduced the cell viability of PC9 cells and initiated cell morphological changes in a concentration-dependent manner. Pemetrexed significantly induced G1 phase arrest in a dose-dependent manner. The results demonstrated that pemetrexed induced apoptosis in PC9 cells, a change coupled with an increase in reactive oxygen species and a decrease in mitochondrial membrane potential. Pemetrexed decreased Bcl-2 expression, while Bax expression was increased, and cytochrome c was released. Furthermore, the expression of extrinsic pathway proteins, e.g. Fas/FasL, DR4/TRAIL, and Fas-associated protein with death domain, was increased by pemetrexed, which then activated caspase-8, caspase-9, and caspase-3 and induced poly (ADP-ribose) polymerase proteolysis. CONCLUSION: This study revealed the mechanisms by which pemetrexed works an anticancer drug in the treatment of NSCLC.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/patologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Éxons , Deleção de Genes , Neoplasias Pulmonares/patologia , Pemetrexede/farmacologia , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Dano ao DNA , Receptores ErbB/genética , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais
18.
Cancer Genomics Proteomics ; 18(4): 579-590, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34183390

RESUMO

BACKGROUND/AIM: Cisplatin combined with pemetrexed disodium heptahydrate (pemetrexed) is considered the standard treatment for patients with advanced, non-squamous, non-small-cell lung cancer. However, its growth-inhibitory effects on KRAS-dependent lung cancer as monotherapy and combination therapy are not well understood. The aim of this study was to compare the effects of cisplatin and pemetrexed on A549 cells as mono- and combination therapies and elucidate the underlying mechanisms. MATERIALS AND METHODS: For in vitro studies, A549 cells were exposed to cisplatin with/without pemetrexed for 72 h. The results were then evaluated by cell viability, apoptosis, reactive oxygen species, terminal deoxynucleotidyl transferase dUTP nick-end labeling, and western blotting assays. RESULTS: Our results revealed that cisplatin monotherapy was most cytotoxic to A549 cells, while cisplatin plus pemetrexed combination had an intermediate effect, and pemetrexed monotherapy induced a minimal cytotoxic effect on A549 cells. This effect was evidenced by cell viability results, inhibition of KRAS proto-oncogene, GTPase (KRAS)/Raf proto-oncogene, serine/threonine kinase/mitogen-activated protein kinase kinase/extracellular signal-regulated kinase pathways and apoptosis induction triggered by reactive oxygen species-mediated DNA damage. The immunoblotting result of conversion of microtubule-associated protein 1 light chain 3 alpha (LC3)-I to -II indicated that the greatest inducer of autophagy was combined treatment with cisplatin plus pemetrexed, while pemetrexed monotherapy had the lowest effect on autophagy induction, with cisplatin monotherapy having an intermediate effect. We found that the AKT serine/threonine kinase 1/mechanistic target of rapamycin kinase (mTOR) and AMP-activated protein kinase/mTOR signaling pathways were associated with autophagy activation. Interestingly, combination therapy with cisplatin plus pemetrexed was the primary eliminator of cellular senescence; cisplatin monotherapy had an intermediate effect, while pemetrexed monotherapy increased cellular senescence of A549 cells, as assessed by the expression of ß-galactosidase protein. CONCLUSION: Cisplatin monotherapy may be more effective than pemetrexed monotherapy or cisplatin plus pemetrexed combination therapy against KRAS-dependent lung cancer.


Assuntos
Antineoplásicos/farmacologia , Cisplatino/farmacologia , Neoplasias Pulmonares/metabolismo , Pemetrexede/farmacologia , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Células A549 , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Senescência Celular/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Humanos , Neoplasias Pulmonares/patologia , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas c-raf/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos
20.
Cancer Treat Res Commun ; 28: 100399, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34023769

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic has triggered a sudden global change in healthcare systems. Cancer patients have a higher risk of death from COVID-19 in comparison to patients without cancer. Many studies have stated that various factors, such as older age, frequent exposure to healthcare, and higher smoking rates are responsible for the complications of COVID-19. We hypothesize that side effects of chemotherapy, such as cellular senescence, could worsen COVID-19. Given this situation, in this review, we highlight the updated findings of research investigating the impact of cellular senescence on COVID-19 complications and explored potential therapeutic targets for eliminating senescent cells during the COVID-19 pandemic.


Assuntos
COVID-19/complicações , COVID-19/patologia , Senescência Celular/fisiologia , Neoplasias/patologia , Senescência Celular/efeitos dos fármacos , Humanos , Terapia de Alvo Molecular , Neoplasias/tratamento farmacológico , Neoplasias/virologia
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