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1.
PLoS Pathog ; 20(6): e1011883, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38838057

RESUMO

ATP-binding cassette (ABC) transport systems are crucial for bacteria to ensure sufficient uptake of nutrients that are not produced de novo or improve the energy balance. The cell surface of the pathobiont Streptococcus pneumoniae (pneumococcus) is decorated with a substantial array of ABC transporters, critically influencing nasopharyngeal colonization and invasive infections. Given the auxotrophic nature of pneumococci for certain amino acids, the Ami ABC transporter system, orchestrating oligopeptide uptake, becomes indispensable in host compartments lacking amino acids. The system comprises five exposed Oligopeptide Binding Proteins (OBPs) and four proteins building the ABC transporter channel. Here, we present a structural analysis of all the OBPs in this system. Multiple crystallographic structures, capturing both open and closed conformations along with complexes involving chemically synthesized peptides, have been solved at high resolution providing insights into the molecular basis of their diverse peptide specificities. Mass spectrometry analysis of oligopeptides demonstrates the unexpected remarkable promiscuity of some of these proteins when expressed in Escherichia coli, displaying affinity for a wide range of peptides. Finally, a model is proposed for the complete Ami transport system in complex with its various OBPs. We further disclosed, through in silico modelling, some essential structural changes facilitating oligopeptide transport into the cellular cytoplasm. Thus, the structural analysis of the Ami system provides valuable insights into the mechanism and specificity of oligopeptide binding by the different OBPs, shedding light on the intricacies of the uptake mechanism and the in vivo implications for this human pathogen.


Assuntos
Transportadores de Cassetes de Ligação de ATP , Proteínas de Bactérias , Oligopeptídeos , Streptococcus pneumoniae , Streptococcus pneumoniae/metabolismo , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Oligopeptídeos/metabolismo , Transportadores de Cassetes de Ligação de ATP/metabolismo , Transportadores de Cassetes de Ligação de ATP/química , Cristalografia por Raios X , Modelos Moleculares , Lipoproteínas
2.
Med Sci Monit ; 30: e944628, 2024 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-38909276

RESUMO

BACKGROUND Cephalometric radiography evaluates facial skeleton development and aids in diagnosis and treatment phases (pre and post) in orthodontics. This study aimed to compare digital cephalometric tracing using a smartphone application (App), a tablet-based platform, and manual tracing in 30 orthodontic patients. MATERIAL AND METHODS Thirty orthodontic pretreatment, criteria based, lateral cephalometric radiographs were analyzed/grouped for Steiner analysis parameters (5 skeletal, 3 dentals, 1 soft tissue) by 3 tracing methods [manual - group (Gp M), smartphone (Android - OS9) - Gp S, tablet (Apple - IOS13) - Gp T) after mandatory standardization/calibration. Measurements include 5 angular (SNA, SNB, ANB, SNMPA, SNOP), 3 linear U1NA, L1NB, U1L1, and 1 soft tissue (S line) (millimeters and degrees). Inter-examiner rating was determined using Dahlberg's test. After normality distribution testing (Shapiro-Wilk), data were analyzed using one-way analysis of variance (ANOVA) for group differences. Homogeneity of variance was verified using the Levene test. Differences were determined on probability value of (p≤0.05). RESULTS The results showed that Steiner's analysis parameters were similar in all groups with homogenous variances. Highest differences in mean values were found for L1NB, U1L1, and S line measurement, with higher values being observed in Gp S tracings. However, these differences were not statistically significant (p≤0.05). All parameters, irrespective of being measured in either degrees or millimeters, had means comparable to each other. CONCLUSIONS Smartphone and tablet-based applications produced tracings that were comparable and reliable when compared to conventional manual tracings. Standardization of images, processing, printing, and calibration of devices is important to achieve good results.


Assuntos
Cefalometria , Aplicativos Móveis , Smartphone , Humanos , Cefalometria/métodos , Masculino , Feminino , Adolescente , Computadores de Mão , Ortodontia/métodos
3.
Odontology ; 112(2): 570-587, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37957521

RESUMO

This study aims to evaluate the number of roots and root canal morphology types of maxillary premolars in relation to a patient's gender and age in an Iraqi population using two classification systems. Cone beam computed tomography (CBCT) scans of 1116 maxillary premolars from 385 patients were evaluated for the number of roots and root canal morphology types according to Vertucci's classification and Ahmed et al. classification systems. Differences in the number of roots and root canal morphology types with regard to tooth type, patients' gender and age groups were evaluated and the degree of bilateral symmetry was determined. Chi-squared test was used for statistical analysis. About 51.1% of the 1st premolars were double rooted. The majority (87.9%) of the 2nd premolars were single rooted. The three-rooted form presented in only 1.2% and 0.7% of the 1st and 2nd premolars, respectively. Vertucci Type IV (Ahmed et al. code 2MaxP B1P1) and Vertucci Type I (Ahmed et al. code 1MaxP1) were the most common canal morphology types in the 1st and 2nd premolars, respectively. Females showed a lower number of roots and a higher prevalence of Vertucci Type I configuration (P < 0.05). Younger age groups showed a higher prevalence of Vertucci Type I configuration (P < 0.05). Bilateral symmetry was seen in more than half of the maxillary premolars. There is a considerable variation in the number of roots and root canal configurations of maxillary premolars in the studied Iraqi population, with a significant difference by gender and age groups. Ahmed et al. classification provided more accurate presentation of the root and canal anatomy in maxillary premolars compared to Vertucci's classification.


Assuntos
Cavidade Pulpar , Raiz Dentária , Feminino , Humanos , Dente Pré-Molar/diagnóstico por imagem , Dente Pré-Molar/anatomia & histologia , Cavidade Pulpar/diagnóstico por imagem , Iraque , Raiz Dentária/diagnóstico por imagem , Maxila/diagnóstico por imagem , Tomografia Computadorizada de Feixe Cônico/métodos
4.
Prostaglandins Other Lipid Mediat ; 169: 106783, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37726053

RESUMO

Crataegus azarolus var. aronia L. (C. aronia) is one of the most important medicinal plants used widely in folk medicine for the prevention of several diseases due to its content of several bioactive compounds like phenolic acid, aromatic amines, proanthocyanidins and flavonoids. This study investigated the uterodilation effect of methanol extract (ME) of C. aronia unripe fruit on the uterine smooth muscle in rats. The mechanism of action underlying the plant's extract was also screened. The unripe fruits were cleaned and extracted in methanol. The extract (1.9-4 mg/ml) was tested on rat uterine relaxation in calcium-free Kreb's solution and potassium chloride-induced uterine contraction. The plant extract was also studied in the presence of antagonists in separate experiments to determine the role of various ion channels and hyperpolarizing agents. The plant extract showed an uterodilation effect on the uterus, in which the ME produced a considerable relaxant effect. The results confirmed that the induced dilation was mediated mainly by the nitric oxide pathway and the activation of potassium channels with a limited role of the prostaglandin pathway and calcium channel activation. This in-vitro study provides the first scientific evidence of the claimed effect of C. aronia on uterine relaxation.


Assuntos
Crataegus , Photinia , Feminino , Ratos , Animais , Frutas , Metanol , Extratos Vegetais/farmacologia , Músculo Liso
5.
Appl Opt ; 62(26): 7008-7016, 2023 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-37707041

RESUMO

In this paper, we propose a new, to the best of our knowledge, saturable absorber (SA) based on sodium carbonate (N a 2 C O 3) for producing an ultrafast mode-locked stretched pulse in a passively erbium-doped fiber laser at near-zero dispersion. The solid film of a N a 2 C O 3-SA was fabricated by the drop-casting method using polyvinyl alcohol as a host polymer. The modulation depth of the proposed SA, which was measured by a balanced twin detector technique, was 2.3% with saturation intensity of 181M W/c m 2. The mode-locking operation of the EDFL-based N a 2 C O 3-SA was observed at a pump power of 117 mW. A stable stretched pulse was generated by using the proposed N a 2 C O 3-SA. The laser can generate pulses with a repetition rate and duration of 1.87 MHz and 820 fs, respectively, within a bandwidth of 6.6 nm. The single pulse energy reaches up to 5 nJ, which is equivalent to the average output power of 9.3 mW. Finally, to the best of our knowledge, this is the first report on using the N a 2 C O 3-SA for generating a stretched-pulse mode-locked fiber laser.

6.
J Enzyme Inhib Med Chem ; 38(1): 2281260, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37994663

RESUMO

Despite the crucial role of CDK2 in tumorigenesis, few inhibitors reached clinical trials for managing lung cancer, the leading cause of cancer death. Herein, we report combinatorial stereoselective synthesis of rationally designed spiroindeno[1,2-b]quinoxaline-based CDK2 inhibitors for NSCLC therapy. The design relied on merging pharmacophoric motifs and biomimetic scaffold hopping into this privileged skeleton via cost-effective one-pot multicomponent [3 + 2] cycloaddition reaction. Absolute configuration was assigned by single crystal x-ray diffraction analysis and reaction mechanism was studied by Molecular Electron Density Theory. Initial MTT screening of the series against A549 cells and normal lung fibroblasts Wi-38 elected 6b as the study hit regarding potency (IC50 = 54 nM) and safety (SI = 6.64). In vitro CDK2 inhibition assay revealed that 6b (IC50 = 177 nM) was comparable to roscovitine (IC50 = 141 nM). Docking and molecular dynamic simulations suggested that 6b was stabilised into CDK2 cavity by hydrophobic interactions with key aminoacids.


Assuntos
Antineoplásicos , Carcinoma Pulmonar de Células não Pequenas , Quinase 2 Dependente de Ciclina , Neoplasias Pulmonares , Humanos , Antineoplásicos/química , Benzimidazóis/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Proliferação de Células , Quinase 2 Dependente de Ciclina/antagonistas & inibidores , Ensaios de Seleção de Medicamentos Antitumorais , Neoplasias Pulmonares/tratamento farmacológico , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Estrutura Molecular , Inibidores de Proteínas Quinases/química , Quinoxalinas
7.
BMC Health Serv Res ; 23(1): 383, 2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-37081467

RESUMO

BACKGROUND: This study attempts to estimate the cost-effectiveness of the antiviral remdesivir, as recommended in the 2021 COVID treatment guidelines for the United Arab Emirates, compared to standard of care (SOC), but also favipiravir (FAVI), which was also recommended for the treatment of hospitalized COVID patients. METHODS: A cost-effectiveness model was built using published efficacy data for RDV, FAVI and SOC as well as local epidemiology data. The outcomes measured included hospital bed days averted, mortality, costs and cost per outcome over one year. One-way, probabilistic and scenario analyses were undertaken to reflect uncertainty in the estimates. RESULTS: When modelled over one year, the results indicated that treatment of adults in need of supplemental oxygen with RDV + SOC could result in 11,338 fewer general ward bed days, 7,003 fewer ICU days and 5,451 fewer ICU + MIV bed days compared to SOC alone and similar results when compared with FAVI + SOC. The model results also showed that there were 374 fewer deaths associated with the use of RDV + SOC compared to SOC alone. The model also estimates substantial potential cost-savings associated with RDV + SOC treatment compared with SOC alone (USD 3,454 per patient). The results of the one-way sensitivity analysis showed that the model was sensitive to estimates of length of stay and the cost of hospitalization. Despite this, the model predicted cost-savings in all scenarios versus all comparators. CONCLUSIONS: The model estimated that using RDV + SOC could result in substantial reductions in HCRU and cost savings regardless of the comparator. However, it should be noted that reliable clinical information on FAVI was limited therefore it is challenging to interpret these results. All the potential benefits modelled here for RDV + SOC can have implications not only for the health of the UAE population but for improving hospital capacity to deal with other conditions.


Assuntos
COVID-19 , Adulto , Humanos , Análise Custo-Benefício , Emirados Árabes Unidos , Hospitalização , Antivirais/uso terapêutico
8.
BMC Musculoskelet Disord ; 24(1): 468, 2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37286979

RESUMO

BACKGROUND: Musculoskeletal disorders are common health problems worldwide. Several factors cause these symptoms, including ergonomics and other individual considerations. Computer users are prone to repetitive strain injuries that increase the risk of developing musculoskeletal symptoms (MSS). Radiologists are susceptible to developing MSS because they work long hours analysing medical images on computers in an increasingly digitalised field. This study aimed to identify the prevalence of MSS among Saudi radiologists and the associated risk factors. METHODS: This study was a cross-sectional, non-interventional, self-administered online survey. The study was conducted on 814 Saudi radiologists from various regions in Saudi Arabia. The study's outcome was the presence of MSS in any body region that limited participation in routine activities over the previous 12 months. The results were descriptively examined using binary logistic regression analysis to estimate the odds ratio (OR) of participants who had disabling MSS in the previous 12 months. All university, public, and private radiologists received an online survey containing questions about work surroundings, workload (e.g., spent at a computer workstation), and demographic characteristics. RESULTS: The prevalence of MSS among the radiologists was 87.7%. Most of the participants (82%) were younger than 40 years of age. Radiography and computed tomography were the most common imaging modalities that caused MSS (53.4% and 26.8%, respectively). The most common symptoms were neck pain (59.3%) and lower back pain (57.1%). After adjustment, age, years of experience, and part-time employment were significantly associated with increased MSS (OR = .219, 95% CI = .057-.836; OR = .235, 95% CI = 087-.634; and OR = 2.673, 95% CI = 1.434-4.981, respectively). Women were more likely to report MSS than males (OR = 2.12, 95% CI = 1.327-3.377). CONCLUSIONS: MSS are common among Saudi radiologists, with neck pain and lower back pain being the most frequently reported symptoms. Gender, age, years of experience, type of imaging modality, and employment status were the most common associated risk factors for developing MSS. These findings are vital for the development of interventional plans to reduce the prevalence of musculoskeletal complaints in clinical radiologists.


Assuntos
Dor Lombar , Doenças Musculoesqueléticas , Doenças Profissionais , Masculino , Humanos , Feminino , Dor Lombar/epidemiologia , Cervicalgia/diagnóstico por imagem , Cervicalgia/epidemiologia , Cervicalgia/complicações , Estudos Transversais , Arábia Saudita/epidemiologia , Doenças Profissionais/diagnóstico por imagem , Doenças Profissionais/epidemiologia , Doenças Profissionais/etiologia , Doenças Musculoesqueléticas/diagnóstico por imagem , Doenças Musculoesqueléticas/epidemiologia , Fatores de Risco , Radiologistas , Prevalência , Inquéritos e Questionários
9.
Arch Pharm (Weinheim) ; 356(8): e2300185, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37253118

RESUMO

A series of 16 novel spirooxindole analogs 8a-p were designed and constructed via cost-effective single-step multicomponent [3+2] cycloaddition reaction of azomethine ylide (AY) generated in situ from substituted isatin (6a-d) with suitable amino acids (7a-c) and ethylene-engrafted pyrazole derivatives (5a,b). The potency of all compounds was assayed against a human breast cancer cell line (MCF-7) and a human liver cell line (HepG2). Spiro compound 8c was the most active member among the synthesized candidates, with exceptional cytotoxicity against the MCF-7 and HepG2 cell lines, with IC50 values of 0.189 ± 0.01 and 1.04 ± 0.21 µM, respectively. The candidate 8c exhibited more potent activity (10.10- and 2.27-fold) than the standard drug roscovitine (IC50 = 1.91 ± 0.17 µM (MCF-7) and 2.36 ± 0.21 µM (HepG2)). Compound 8c was investigated for epidermal growth factor receptor (EGFR) inhibition; it exhibited promising IC50 values of 96.6 nM compared with 67.3 nM for erlotinib. The IC50 value of 8c (34.98 nM) exhibited cyclin-dependent kinase 2 (CDK-2) inhibition, being more active than roscovitine the (IC50 = 140 nM) in targeting the CDK-2 kinase enzyme. Additionally, for apoptosis induction of compound 8c in MCF-7, it upregulated the expression levels of proapoptotic genes for P53, Bax, caspases-3, 8, and 9 at up to 6.18, 4.8, 9.8, 4.6, 11.3 fold-change, respectively, and downregualted the level of the antiapoptotic gene for Bcl-2 by 0.14-fold. Finally, a molecular docking study of the most active compound 8c highlighted a good binding affinity with Lys89 as the key amino acid for CDK-2 inhibition.


Assuntos
Antineoplásicos , Humanos , Oxindóis/farmacologia , Oxindóis/química , Linhagem Celular Tumoral , Relação Estrutura-Atividade , Roscovitina/farmacologia , Simulação de Acoplamento Molecular , Antineoplásicos/química , Proliferação de Células , Ensaios de Seleção de Medicamentos Antitumorais , Estrutura Molecular , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/química , Apoptose
10.
Molecules ; 28(19)2023 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-37836817

RESUMO

A new series of spirooxindoles based on benzimidazole, triazole, and isatin moieties were synthesized via a [3+2] cycloaddition reaction protocol in one step. The single X-ray crystal structure of the intermediate triazole-benzimidazole 4 was solved. The new chemical structures of these spirooxindole molecules have been achieved for the first time. The final synthesized chemical architecture has differently characterized electronic effects. An MEDT study of the key 32CA reaction between in situ generated azomethine ylide (AY) and chalcones explained the low reaction rates and the total selectivities observed. The supernucleophilic character of AY and the strong electrophilicity of chalcones favor these reactions through a highly polar two-stage one-step mechanism in which bond formation at the ß-conjugated carbon of the chalcones is more advanced. The present combined experimental and theoretical study reports the synthesis of new spirooxindoles with potential biological activities and fully characterizes the molecular mechanisms for their formation through the key 32CA reaction step.

11.
Molecules ; 28(18)2023 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-37764399

RESUMO

Diabetes is a chronic metabolic disorder of the endocrine system characterized by persistent hyperglycemia appears due to the deficiency or ineffective use of insulin. The glucose level of diabetic patients increases after every meal and medically recommended drugs are used to control hyperglycemia. Alpha-glucosidase inhibitors are used as antidiabetic medicine to delay the hydrolysis of complex carbohydrates. Acarbose, miglitol, and voglibose are commercial drugs but patients suffer side effects of flatulence, bloating, diarrhea, and loss of hunger. To explore a new antidiabetic drug, a series of benzotriazinone carboxamides was synthesized and their alpha-glucosidase inhibition potentials were measured using in vitro experiments. The compounds 14k and 14l were found to be strong inhibitors compared to the standard drug acarbose with IC50 values of 27.13 ± 0.12 and 32.14 ± 0.11 µM, respectively. In silico study of 14k and 14l was carried out using molecular docking to identify the type of interactions developed between these compounds and enzyme sites. Both potent compounds 14k and 14l exhibited effective docking scores by making their interactions with selected amino acid residues. Chemical hardness and orbital energy gap values were investigated using DFT studies and results depicted affinity of 14k and 14l towards biological molecules. All computational findings were found to be in good agreement with in vitro results.

12.
Angew Chem Int Ed Engl ; 62(35): e202306154, 2023 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-37341676

RESUMO

Nuclear Magnetic Resonance (NMR) spectra of human serum and plasma show, besides metabolites and lipoproteins, two characteristic signals termed GlycA and B arising from the acetyl groups of glycoprotein glycans from acute phase proteins, which constitute good markers for inflammatory processes. Here, we report a comprehensive assignment of glycoprotein glycan NMR signals observed in human serum, showing that GlycA and GlycB signals originate from Neu5Ac and GlcNAc moieties from N-glycans, respectively. Diffusion-edited NMR experiments demonstrate that signal components can be associated with specific acute phase proteins. Conventionally determined concentrations of acute phase glycoproteins correlate well with distinct features in NMR spectra (R2 up to 0.9422, p-value <0.001), allowing the simultaneous quantification of several acute phase inflammation proteins. Overall, a proteo-metabolomics NMR signature of significant diagnostic potential is obtained within 10-20 min acquisition time. This is exemplified in serum samples from COVID-19 and cardiogenic shock patients showing significant changes in several acute phase proteins compared to healthy controls.


Assuntos
Proteínas de Fase Aguda , COVID-19 , Humanos , Proteínas de Fase Aguda/metabolismo , Biomarcadores/metabolismo , Inflamação/metabolismo , Espectroscopia de Ressonância Magnética , Glicoproteínas/metabolismo , Polissacarídeos/química
13.
Pharmacol Res ; 178: 106147, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35227891

RESUMO

CTLA4-Ig is a potent costimulatory blocker that inhibits T cell activation during alloimmune inflammation and increases graft survival and function. CTLA4-Ig-mediated immunosuppression has been demonstrated to support transplant function in various clinical trials and preclinical settings, but its effects on the balance between regulatory T cells (Tregs) and effector T cells (Teffs), as well as complement activation, are less well investigated. In the present study, we proposed to investigate the effects of CTLA4-Ig mediated immunosuppression on the phase of immunotolerance and the subsequent graft microvascular and epithelial repair during the progression of subepithelial fibrosis in a mouse model of orthotopic trachea transplantation. Briefly, CTLA4-Ig treated allografts (2 mg/kg, I.P.), untreated allografts, and syngrafts were serially monitored for peripheral FOXP3+ Tregs, antibody-mediated complement activation (C3d and C4d), tissue oxygenation, donor-recipient microvascular blood flow, and subsequent tissue remodeling following transplantation. Our data demonstrate that CTLA4-Ig mediated immunosuppression significantly results in late increases in both peripheral CD4+/CD8+ FOXP3+ Tregs and serum IL-10, but prevents the microvascular deposition of IgG, complement factor C3d, and epithelial C4d respectively, which proportionally improved blood flow and tissue oxygenation in the graft and, thus, promotes graft repair. Also, it restored the airway lumen, epithelium, and prevented the progression of subepithelial collagen deposition up to 90 days after transplantation. This study demonstrates that CTLA4-Ig-mediated immunosuppression potentially modulates both effector response and a late surge of regulatory activity to preserve graft microvasculature and rescue allograft from sustained hypoxia and ischemia and thereby limits subepithelial fibrosis.


Assuntos
Antígeno CTLA-4 , Rejeição de Enxerto , Sobrevivência de Enxerto , Abatacepte/farmacologia , Abatacepte/uso terapêutico , Animais , Antígeno CTLA-4/administração & dosagem , Antígeno CTLA-4/imunologia , Fibrose , Fatores de Transcrição Forkhead , Rejeição de Enxerto/imunologia , Rejeição de Enxerto/prevenção & controle , Sobrevivência de Enxerto/imunologia , Terapia de Imunossupressão , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Linfócitos T Reguladores/imunologia , Traqueia/transplante
14.
J Clin Lab Anal ; 36(4): e24291, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35261080

RESUMO

BACKGROUND: This study investigates in-hospital mortality amongst patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its relation to serum levels of gamma-glutamyl transferase (GGT). METHODS: Patients were stratified according to serum levels of gamma-glutamyl transferase (GGT) (GGT<50 IU/L or GGT≥50 IU/L). RESULTS: A total of 802 participants were considered, amongst whom 486 had GGT<50 IU/L and a mean age of 48.1 (16.5) years, whilst 316 had GGT≥50 IU/L and a mean age of 53.8 (14.7) years. The chief sources of SARS-CoV-2 transmission were contact (366, 45.7%) and community (320, 40%). Most patients with GGT≥50 IU/L had either pneumonia (247, 78.2%) or acute respiratory distress syndrome (ARDS) (85, 26.9%), whilst those with GGT<50 IU/L had hypertension (141, 29%) or diabetes mellitus (DM) (147, 30.2%). Mortality was higher amongst patients with GGT≥50 IU/L (54, 17.1%) than amongst those with GGT<50 IU/L (29, 5.9%). More patients with GGT≥50 required high (83, 27.6%) or low (104, 34.6%) levels of oxygen, whereas most of those with GGT<50 had no requirement of oxygen (306, 71.2%). Multivariable logistic regression analysis indicated that GGT≥50 IU/L (odds ratio [OR]: 2.02, 95% confidence interval [CI]: 1.20-3.45, p=0.009), age (OR: 1.05, 95% CI: 1.03-1.07, p<0.001), hypertension (OR: 2.06, 95% CI: 1.19-3.63, p=0.011), methylprednisolone (OR: 2.96, 95% CI: 1.74-5.01, p<0.001) and fever (OR: 2.03, 95% CI: 1.15-3.68, p=0.016) were significant predictors of all-cause cumulative mortality. A Cox proportional hazards regression model (B = -0.68, SE =0.24, HR =0.51, p = 0.004) showed that patients with GGT<50 IU/L had a 0.51-times lower risk of all-cause cumulative mortality than patients with GGT≥50 IU/L. CONCLUSION: Higher levels of serum GGT were found to be an independent predictor of in-hospital mortality.


Assuntos
COVID-19 , Hipertensão , Mortalidade Hospitalar , Humanos , Pessoa de Meia-Idade , Oxigênio , Fatores de Risco , SARS-CoV-2 , gama-Glutamiltransferase
15.
Chaos ; 32(8): 083133, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36049931

RESUMO

As the shortest feedback loop of the nervous system, autapse plays an important role in the mode conversion of neurodynamics. In particular, memristive autapses can not only facilitate the adjustment of the dynamical behavior but also enhance the complexity of the nervous system, in view of the fact that the dynamics of the Hopfield neural network has not been investigated and studied in detail from the perspective of memristive autapse. Based on the traditional Hopfield neural network, this paper uses a locally active memristor to replace the ordinary resistive autapse so as to construct a 2 n-dimensional memristive autaptic Hopfield neural network model. The boundedness of the model is proved by introducing the Lyapunov function and the stability of the equilibrium point is analyzed by deriving the Jacobian matrix. In addition, four scenarios are established on a small Hopfield neural network with three neurons, and the influence of the distribution of memristive autapses on the dynamics of this small Hopfield neural network is described by numerical simulation tools. Finally, the Hopfield neural network model in these four situations is designed and implemented on field-programmable gate array by using the fourth-order Runge-Kutta method, which effectively verifies the numerical simulation results.


Assuntos
Redes Neurais de Computação , Neurônios , Simulação por Computador , Retroalimentação , Neurônios/fisiologia
16.
Drug Chem Toxicol ; 45(1): 127-132, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31505969

RESUMO

In this work, we developed a simple spectrophotometric strategy for BrO3- ions determination as a major water disinfection constituents in the mice's liver tissues by using pararosaniline (PRA). Mice were divided into seven main groups (6 doses): lowest dose KBrO3 (G1 0.01 mg L-1, G2 0.025 mg L-1 and G3 0.1 mg L-1), highest dose KBrO3 (G4 1 mg L-1, G5 10 mg·L-1 and G6 30 mg L-1) and control. All these groups maintained a dose-specific feeding for one month, just before the bromate assessment in mice's liver samples. The results revealed that groups of exposure to lower doses of drinking water did not detect the presence of BrO3- accumulated in the liver tissue during the study period (1-2 months). While, the BrO3- was detected in higher dosages for samples analyzed in first, second, third, fourth and fifth weeks (W1, W2, W3, W4, and W5). These results confirmed that the higher BrO3- dosages (1, 10, and 30 mg L-1) were fatal if introduced in drinking water and could accumulate in the liver tissues both for mice and for human. Detection the accuracy of the method for recovery of bromate ions in liver samples (N = 5) was found to be more than 95%. Relative standard deviations (RSDs) were found to be less than 2.0% confirming the reproducibility of the assay technique.


Assuntos
Bromatos , Fígado , Administração Oral , Animais , Bromatos/toxicidade , Masculino , Camundongos , Reprodutibilidade dos Testes
17.
Plant Dis ; 2022 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-35196105

RESUMO

Fig (Ficus carica L.) is widely grown in Oman mainly for its nutritional value and health benefits. In May 2020, survey was conducted for fig trees which were showing symptoms of decline in three farms where more than 1500 fig trees were grown. The incidence of the disease was 3 to 4 % of fig trees showing symptoms of dieback of the twigs, death of entire branch and discoloration of vascular tissues were observed in Sohar, North Al-Batinah governorate of Oman. The disease severity was range between 25 to 40 % in most of the infected tree. The death of severely affected trees was observed in about 3 % of the orchards. Symptomatic samples were collected and isolation of the causal agent was performed. Infected tissues were cut into small pieces and surface-sterilized with 1 % NaOCl for 3 min. The tissues were rinsed with sterile distilled water 3-4 times, blotted dry on sterile filter paper and placed on potato dextrose agar (PDA) medium under aseptic conditions. After 2-3 days of incubation of plates at 27°C, pure culture of the fungus was obtained by hyphal tip isolation technique. Two identical isolates were grown in the PDA medium. The fungal colony was dark grey to black colored on PDA medium and the fungus produced dense aerial mycelium and numerous dark colored pycnidia in 25 days at ambient temperature range between 23-25 ℃ and nature photoperiod. Pycnidia were raptured and 20 emerged conidia were measured. The mature conidia were 1-septate, brown, ellipsoid, with thick cell wall and having longitudinal striation. The average measurement of the length of 20 conidia was 22.5-25 (24.9 µm) however the width measured was 12.5-15 (15 µm). To identify the fungus, DNA was extracted from the mycelium using phenol-chloroform-isoamyl alcohol method, following Al-Mahmooli et al. (2015). The internal transcribed spacer (ITS) region of ribosomal DNA (rDNA) and translation elongation factor 1-α (TEF) gene were amplified using ITS-4 and ITS-5 primers for ITS (White et al. 1990), EF1-983F and EF1-2218R and EF1-728F and EF1-986R primers for TEF (Alves et al. 2008), respectively and the amplified products were sequenced. BLASTn analysis of the ITS sequence of the fungal isolate revealed 100% identity with reference sequences of Lasiodiplodia theobromae (Pat.) Griffon & Maubl (MT075438.1). The sequence of TEF gene was 99% identical to the sequences of L. theobromae (XM_035519539.1 and MN461169.1). The nucleotide sequences were submitted to GenBank and accessioned with (MW590660) for ITS and (MZ159970, MZ159971, OM654917) for TEF gene. For phylogenetic analysis, we constructed a combined ITS-TEF dataset, following (Alves et. 2008). Using Maximum Likelihood phylogenetic analysis of the combined ITS-TEF dataset, our specimen falls in a clade formed by the members of L. theobromae (Supplementary materials). Pathogenicity of the fungus of three replicates (three fig seedlings) was established by artificial inoculation of 2- to 3-month-old potted fig seedlings with the fungus by making pin prick injuries on the stem at 5 cm above the soil level with a sterile inoculation needle, placing mycelial discs containing spores and pycnidia (15 × 15 mm) from 20-days old colonies grown on PDA on the injured surface and wrapping with parafilm which removed 48 hrs after establishing of infection. The three inoculated plants showed withering and drying of leaves 14 days after inoculation (DAI) begins near to the inoculation site expend to the younger leaves. Eventually, seedlings were showing dieback and death of entire seedling occurs in 25-28 DAI. The mock-inoculated plants remained symptomless. The fungus re-isolated from the diseased plants was confirmed by sequencing of ITS regions. The prevalence of dieback could be a potential threat to cultivation of fig in Oman. To the best of our knowledge, this is the first report of dieback disease caused by L. theobromae on fig in Oman.

18.
Int J Mol Sci ; 23(16)2022 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-36012179

RESUMO

This study examined the efficiency of fungal strain (Cunninghamella bertholletiae) isolated from the rhizosphere of Solanum lycopersicum to reduce symptoms of salinity, drought and heavy metal stresses in tomato plants. In vitro evaluation of C. bertholletiae demonstrated its ability to produce indole-3-Acetic Acid (IAA), ammonia and tolerate varied abiotic stresses on solid media. Tomato plants at 33 days' old, inoculated with or without C. bertholletiae, were treated with 1.5% sodium chloride, 25% polyethylene glycol, 3 mM cadmium and 3 mM lead for 10 days, and the impact of C. bertholletiae on plant performance was investigated. Inoculation with C. bertholletiae enhanced plant biomass and growth attributes in stressed plants. In addition, C. bertholletiae modulated the physiochemical apparatus of stressed plants by raising chlorophyll, carotenoid, glucose, fructose, and sucrose contents, and reducing hydrogen peroxide, protein, lipid metabolism, amino acid, antioxidant activities, and abscisic acid. Gene expression analysis showed enhanced expression of SlCDF3 and SlICS genes and reduced expression of SlACCase, SlAOS, SlGRAS6, SlRBOHD, SlRING1, SlTAF1, and SlZH13 genes following C. bertholletiae application. In conclusion, our study supports the potential of C. bertholletiae as a biofertilizer to reduce plant damage, improve crop endurance and remediation under stress conditions.


Assuntos
Cunninghamella , Solanum lycopersicum , Solanum lycopersicum/genética , Rizosfera , Estresse Fisiológico/genética
19.
Int J Mol Sci ; 23(19)2022 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-36233160

RESUMO

The search for an effective anti-viral to inhibit COVID-19 is a challenge for the specialized scientific research community. This work investigated the anti-coronavirus activity for spirooxindole-based phenylsulfone cycloadducts in a single and combination protocols. The newly designed anti-SARS-CoV-2 therapeutics spirooxindoles synthesized by [3 + 2] cycloaddition reactions represent an efficient approach. One-pot multicomponent reactions between phenyl vinyl sulfone, substituted isatins, and amines afforded highly stereoselective anti-SARS-CoV-2 therapeutics spirooxindoles with three stereogenic centers. Herein, the newly synthesized spirooxindoles were assessed individually against the highly pathogenic human coronaviruses and proved to be highly potent and safer. Interestingly, the synergistic effect by combining the potent, tested spirooxindoles resulted in an improved antiviral activity as well as better host-cell safety. Compounds 4i and 4d represented the most potent activity against MERS-CoV with IC50 values of 11 and 23 µM, respectively. Both compounds 4c and 4e showed equipotent activity with the best IC50 against SARS-CoV-2 with values of 17 and 18 µM, respectively, then compounds 4d and 4k with IC50 values of 24 and 27 µM, respectively. Then, our attention oriented to perform a combination protocol as anti-SARS-CoV-2 for the best compounds with a different binding mode and accompanied with different pharmacophores. Combination of compound 4k with 4c and combination of compounds 4k with 4i proved to be more active and safer. Compounds 4k with 4i displayed IC50 = 3.275 µM and half maximal cytotoxic-concentration CC50 = 11832 µM. MD simulation of the most potential compounds as well as in silico ADMET properties were investigated. This study highlights the potential drug-like properties of spirooxindoles as a cocktail anti-coronavirus protocol.


Assuntos
Tratamento Farmacológico da COVID-19 , Coronavírus da Síndrome Respiratória do Oriente Médio , Aminas/farmacologia , Antivirais/química , Antivirais/farmacologia , Humanos , Simulação de Acoplamento Molecular , SARS-CoV-2
20.
Molecules ; 27(23)2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36500681

RESUMO

Doxorubicin (DOXO) is an antineoplastic drug that is used extensively in managing multiple cancer types. However, DOXO-induced cardiotoxicity is a limiting factor for its widespread use and considerably affects patients' quality of life. Farnesol (FSN) is a sesquiterpene with antioxidant, anti-inflammatory, and anti-tumor properties. Thus, the current study explored the cardioprotective effect of FSN against DOXO-induced cardiotoxicity. In this study, male Wistar rats were randomly divided into five groups (n = 7) and treated for 14 days. Group I (Control): normal saline, p.o. daily for 14 days; Group II (TOXIC): DOXO 2.4 mg/kg, i.p, thrice weekly for 14 days; Group III: FSN 100 mg/kg, p.o. daily for 14 days + DOXO similar to Group II; Group IV: FSN 200 mg/kg, p.o. daily for 14 days + DOXO similar to Group II; Group V (Standard): nifedipine 10 mg/kg, p.o. daily for 14 days + DOXO similar to Group II. At the end of the study, animals were weighed, blood was collected, and heart-weight was measured. The cardiac tissue was used to estimate biochemical markers and for histopathological studies. The observed results revealed that the FSN-treated group rats showed decrease in heart weight and heart weight/body weight ratio, reversed the oxidative stress, cardiac-specific injury markers, proinflammatory and proapoptotic markers and histopathological aberrations towards normal, and showed cardioprotection. In summary, the FSN reduces cardiac injuries caused by DOXO via its antioxidant, anti-inflammatory, and anti-apoptotic potential. However, more detailed mechanism-based studies are needed to bring this drug into clinical use.


Assuntos
Farneseno Álcool , Qualidade de Vida , Masculino , Ratos , Animais , Ratos Wistar , Farneseno Álcool/farmacologia , Farneseno Álcool/uso terapêutico , Miócitos Cardíacos , Cardiotoxicidade/tratamento farmacológico , Cardiotoxicidade/etiologia , Cardiotoxicidade/prevenção & controle , Doxorrubicina/farmacologia , Morte Celular , Estresse Oxidativo , Inflamação/metabolismo , Antioxidantes/metabolismo
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