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1.
Opt Express ; 32(9): 15978-15992, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38859236

RESUMO

This paper presents a laboratory study of the aberrations calculation in underwater turbulence using the Shack-Hartmann wavefront sensor. The wavefront decomposition method and Zernike polynomials determine the aberration parameters. In our experimental setup, the turbulent phase screen generator is located in two locations: near the transmitter and therefore far from the receiver, and near the receiver and consequently far from the transmitter. Additionally, we investigate the impact of aperture diameter on turbulence-induced aberrations in the optical receiver system. However, it is essential to note that the coefficients of Zernike polynomials obtained using this method are subject to errors caused by receiver sensor noise and correlation between the polynomials. To address this, we first calculate the coefficients in different arrangements and then correct measurement errors arising from sensor noise and polynomial coefficient correlation.

2.
Odontology ; 111(2): 461-473, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36350427

RESUMO

Dental pulp stem cells (DPSCs) are a new type of mesenchymal stem cells (MSCs) found in the oral cavity with immunomodulation and tissue regeneration capacities. This study determined the impacts of nano-hydroxyapatite (nHA) prepared through Elaeagnus Angustifolia extract (EAE) to enhance the relative expression of immunomodulatory/dentin-pulp regeneration genes in DPSCs. To produce nHA and modified nHA via EAE (nHAEA), the sol-gel technique was used. The functional groups of nanoparticles (NPs), morphological, and optical features were determined using Fourier transform infrared (FTIR), X-ray diffraction (XRD), Scanning electron microscopy (SEM) together with energy-dispersive X-ray analysis (EDAX), and Transmission electron microscopy (TEM). The cell viability was then determined using the MTT method in the presence of various EAE, nHA, and nHAEA concentrations. Target gene expression was quantified using a real-time PCR procedure after treating DPSCs with an optimally non-toxic dose of EAE and NPs. The presence of the HA phase was reported with the XRD and FTIR results. According to the results of SEM and TEM, the rod-like NPs could be fabricated. nHAEAs were found to be characterized with low crystallite size, reduced diameter, lengthier, needle-like, and less agglomerated particles compared with nHA. The real-time PCR results demonstrated that nHAEA remarkably increased the expression of human leukocyte antigen-G5 (HLA-G5), vascular endothelial growth factor (VEGF), dentin sialophosphoprotein (DSPP), and interleukin6 (IL6) genes compared to the nHA group. These findings suggest that nHAEAs might have the potential application in the stemness capability of DPSCs for the treatment of inflamed/damaged pulp.


Assuntos
Polpa Dentária , Durapatita , Humanos , Durapatita/farmacologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Células-Tronco , Regeneração , Diferenciação Celular , Dentina , Células Cultivadas , Proliferação de Células
3.
Curr Microbiol ; 79(4): 102, 2022 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-35152319

RESUMO

Antibiotic resistance is already widespread in the world, and it has become a great health problem. Therefore, comprehensive efforts are needed to minimize the resistance. The exploration of alternative therapies may offer a more targeted approach with less susceptibility to resistance. Even though antimicrobial peptides (AMPs) have been introduced as emerging antibiotic sources, they are not widely discussed in the literature. Since Neisseria infections show resistance to different types of antibiotics, the purpose of this review was to discuss the currently investigated AMPs with anti-Neisseria properties. In the present review, we provide an overview of 24 AMPs with in vitro anti-Neisseria properties.


Assuntos
Peptídeos Catiônicos Antimicrobianos , Peptídeos Antimicrobianos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Peptídeos Catiônicos Antimicrobianos/farmacologia , Resistência Microbiana a Medicamentos , Neisseria
4.
Microb Pathog ; 144: 104198, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32283259

RESUMO

HTLV-1, the first human oncogenic retrovirus, is a type C retrovirus that belongs to the Deltaretrovirus genus. The HTLV-1 genome has 8.5 kbp length, and consists of major genes such as gag, pol, pro, env, and pX region. This retrovirus is considered as one of the most deadly infectious agent for peripheral-blood mononuclear cells (PBMC). The infection of HTLV-1 can lead to dangerous complications, such as infective dermatitis (ID), uveitis, arthritis, lymphadenitis, arthropathies, Sjögren's Syndrome (SS), and particularly HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) or Adult T-Cell Leukemia Lymphoma (ATLL). At the moment, Zidovudine (AZT) plus IFN-α is the only treatment available for HTLV-1 infections. Based on scientific studies, alongside the therapeutic regimens, intrinsic mechanisms also play a determinant role in reducing the signs of disease. Programmed cell death-1 (PD-1) signaling pathway, one of the most important checkpoints, has recently received interest, such as the development of a novel generation of anti-tumors. In the present study, we discuss the role of PD-1 signaling pathway in HTLV-1 infection as well as its application as a novel approach for treatment of HTLV-1 infections.


Assuntos
Infecções por HTLV-I/tratamento farmacológico , Vírus Linfotrópico T Tipo 1 Humano/efeitos dos fármacos , Vírus Linfotrópico T Tipo 1 Humano/genética , Terapia de Alvo Molecular/métodos , Receptor de Morte Celular Programada 1/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Adulto , Antígenos CD/química , Antígeno CTLA-4/química , Doença Crônica , Infecções por HTLV-I/complicações , Infecções por HTLV-I/virologia , Receptor Celular 2 do Vírus da Hepatite A/química , Humanos , Interferon-alfa/farmacologia , Leucócitos Mononucleares/virologia , Paraparesia Espástica Tropical , Receptor de Morte Celular Programada 1/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 11/química , Receptores Imunológicos/química , Zidovudina/farmacologia , Proteína do Gene 3 de Ativação de Linfócitos
5.
J Opt Soc Am A Opt Image Sci Vis ; 35(8): 1427-1437, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30110280

RESUMO

In this paper, on the basis of the extended Huygens-Fresnel principle, a semi-analytical expression for describing the on-axis scintillation index of a partially coherent flat-topped laser beam through non-Kolmogorov maritime and terrestrial atmospheric environments on a slant path is derived. Consequently, by using the log-normal intensity probability density function, the bit error rate (BER) is evaluated. The effects of source factors (such as wavelength, order of flatness, and beam width) and the non-Kolmogorov turbulent atmosphere parameters (such as the Kolmogorov inner scale, the spectral power-law exponent, and the turbulence structure constant) on propagation behavior of the scintillation index, and hence on the BER, are studied in detail. Results indicate that an increase in the average SNR causes a greater influence of the power-law exponent on the BER. Also, it can be deduced that the mean BER increases while the power-law exponent decreases. In addition, the scintillation index and BER as communication link parameters represent the fact that increasing the atmospheric refractive-index structure parameter on the ground and decreasing the inner scale of turbulence eddies causes an increase in these parameters.

6.
Microb Pathog ; 111: 71-74, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28826767

RESUMO

Efflux pumps are well known as a key role to fluoroquinolone resistance in methicillin-resistant Staphylococcus aureus (MRSA). In this study, among 60 clinical MRSA isolates, 42 isolates (70%) were resistant to ciprofloxacin. MRSA were isolated to detect efflux genes including norA, norB, norC, mepA, sepA, mdeA, qacA/B and smr. Isolates subjected to PCR detection and DNA sequence analysis for these genes. PCR detection showed that 42 isolates (70%) contained at least one efflux pump gene. Among ciprofloxacin-resistant isolates, mdeA and qacA/B genes were found with the highest (61.7%) and lowest (3.3%) frequency, respectively. We also observed that the highest minimum inhibitory concentrations of ciprofloxacin in the presence of mdeA+mepA+norA-C+sepA+smr combination. This type of combination may have the greatest impact on resistance to ciprofloxacin. Finally, compared to previous studies, our study demonstrates that prevalence of ciprofloxacin resistance has been increasing among MRSA clinical isolates.


Assuntos
Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Ciprofloxacina/farmacologia , Frequência do Gene/genética , Genes Bacterianos/genética , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/genética , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Sangue/microbiologia , DNA Bacteriano/genética , Fluoroquinolonas/farmacologia , Humanos , Irã (Geográfico) , Proteínas de Membrana Transportadoras/genética , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Testes de Sensibilidade Microbiana , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Escarro/microbiologia , Infecções Estafilocócicas/microbiologia , Urina/microbiologia , Ferimentos e Lesões/microbiologia
7.
J Opt Soc Am A Opt Image Sci Vis ; 34(12): 2126-2137, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-29240086

RESUMO

In this paper, the performance of underwater wireless optical communication (UWOC) links, which is made up of the partially coherent flat-topped (PCFT) array laser beam, has been investigated in detail. Providing high power, array laser beams are employed to increase the range of UWOC links. For characterization of the effects of oceanic turbulence on the propagation behavior of the considered beam, using the extended Huygens-Fresnel principle, an analytical expression for cross-spectral density matrix elements and a semi-analytical one for fourth-order statistical moment have been derived. Then, based on these expressions, the on-axis scintillation index of the mentioned beam propagating through weak oceanic turbulence has been calculated. Furthermore, in order to quantify the performance of the UWOC link, the average bit error rate (BER) has also been evaluated. The effects of some source factors and turbulent ocean parameters on the propagation behavior of the scintillation index and the BER have been studied in detail. The results of this investigation indicate that in comparison with the Gaussian array beam, when the source size of beamlets is larger than the first Fresnel zone, the PCFT array laser beam with the higher flatness order is found to have a lower scintillation index and hence lower BER. Specifically, in the sense of scintillation index reduction, using the PCFT array laser beams has a considerable benefit in comparison with the single PCFT or Gaussian laser beams and also Gaussian array beams. All the simulation results of this paper have been shown by graphs and they have been analyzed in detail.

8.
Ann Hepatol ; 16(2): 207-214, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28233741

RESUMO

BACKGROUND: Patients with chronic hepatitis B virus (HBV) are often treated with nucleoside/nucleotide antiviral agents and metabolic bone toxicity is a possible concern. OBJECTIVE: To determine the relationships between fibroblast growth factor 23 (FGF23), a phosphaturic hormone, bone mineral density (BMD), and bone biochemical abnormalities in these patients. MATERIAL AND METHODS: This is a cross-sectional observational study comparing HBV-infected subjects treated for at least one year with tenofovir (TDF), lamuvidine (LVD), entacavir (ETV), or not treated (CON). Patients with abnormalities in either calcium (Ca), phosphate (PO4), intact parathyroid hormone (iPTH) or FGF23 were further evaluated with BMD by DXA. RESULTS: No difference in liver enzymes or renal function seen among groups, but hypophosphatemia was seen in all groups with the highest incidence with TDF-treatment (14%). FGF 23 levels were found to be elevated in 11.1% of TDF patients, 2.77% amongst controls. No elevations were found in the LVD or ETV groups. Among a subset of subjects (FGF23, PO4, and/or Ca abnormalities) who underwent further evaluation, 67% had insufficient 25-OH vitamin D, and 30% had elevated 24 h urinary Ca or PO4 excretion. No patients with FGF23 abnormalities had urine abnormalities. 40% had low DXA Z-score (<-2) at spine or hip but there was no difference between control and antiviral treatment groups and the mean FRAX score was 2.33% for major osteoporotic fractures and 0.29% for hip fracture. CONCLUSION: Abnormalities in bone metabolism, particularly involving vitamin D insufficiency, in HBV-treated subjects were observed with a small increased likelihood in TDF treated patients.


Assuntos
Antivirais/uso terapêutico , Osso e Ossos/efeitos dos fármacos , Cálcio/sangue , Fatores de Crescimento de Fibroblastos/sangue , Guanina/análogos & derivados , Hepatite B Crônica/tratamento farmacológico , Lamivudina/uso terapêutico , Fosfatos/sangue , Tenofovir/uso terapêutico , Absorciometria de Fóton , Adulto , Idoso , Antivirais/efeitos adversos , Biomarcadores/sangue , Densidade Óssea/efeitos dos fármacos , Remodelação Óssea/efeitos dos fármacos , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/metabolismo , Estudos Transversais , Feminino , Fator de Crescimento de Fibroblastos 23 , Fraturas Ósseas/induzido quimicamente , Guanina/efeitos adversos , Guanina/uso terapêutico , Hepatite B Crônica/sangue , Hepatite B Crônica/diagnóstico , Humanos , Lamivudina/efeitos adversos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Tenofovir/efeitos adversos , Fatores de Tempo , Resultado do Tratamento , Deficiência de Vitamina D/induzido quimicamente
9.
Proc Natl Acad Sci U S A ; 111(9): 3620-5, 2014 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-24550511

RESUMO

Amyotrophic lateral sclerosis (ALS) is predominantly sporadic, but associated with heritable genetic mutations in 5-10% of cases, including those in Cu/Zn superoxide dismutase (SOD1). We previously showed that misfolding of SOD1 can be transmitted to endogenous human wild-type SOD1 (HuWtSOD1) in an intracellular compartment. Using NSC-34 motor neuron-like cells, we now demonstrate that misfolded mutant and HuWtSOD1 can traverse between cells via two nonexclusive mechanisms: protein aggregates released from dying cells and taken up by macropinocytosis, and exosomes secreted from living cells. Furthermore, once HuWtSOD1 propagation has been established, misfolding of HuWtSOD1 can be efficiently and repeatedly propagated between HEK293 cell cultures via conditioned media over multiple passages, and to cultured mouse primary spinal cord cells transgenically expressing HuWtSOD1, but not to cells derived from nontransgenic littermates. Conditioned media transmission of HuWtSOD1 misfolding in HEK293 cells is blocked by HuWtSOD1 siRNA knockdown, consistent with human SOD1 being a substrate for conversion, and attenuated by ultracentrifugation or incubation with SOD1 misfolding-specific antibodies, indicating a relatively massive transmission particle which possesses antibody-accessible SOD1. Finally, misfolded and protease-sensitive HuWtSOD1 comprises up to 4% of total SOD1 in spinal cords of patients with sporadic ALS (SALS). Propagation of HuWtSOD1 misfolding, and its subsequent cell-to-cell transmission, is thus a candidate process for the molecular pathogenesis of SALS, which may provide novel treatment and biomarker targets for this devastating disease.


Assuntos
Esclerose Lateral Amiotrófica/fisiopatologia , Exossomos/metabolismo , Dobramento de Proteína , Superóxido Dismutase/química , Esclerose Lateral Amiotrófica/metabolismo , Animais , Linhagem Celular , Eletroforese em Gel de Poliacrilamida , Humanos , Camundongos , Microscopia Eletrônica , Pinocitose/fisiologia , Interferência de RNA , RNA Interferente Pequeno/genética , Superóxido Dismutase/metabolismo
10.
Can J Neurol Sci ; 43(6): 791-795, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27476760

RESUMO

BACKGROUND: Amyotrophic lateral sclerosis (ALS) is a fatal degenerative neurological disease with significant effects on quality of life. International studies continue to provide consistent incidence values, though complete case ascertainment remains a challenge. The Canadian population has been understudied, and there are currently no quantitative data on the incidence of ALS in British Columbia (BC). The objectives of this study were to determine the five-year incidence rates of ALS in BC and to characterize the demographic patterns of the disease. METHODS: The capture-recapture method was employed to estimate ALS incidence over a five-year period (2010-2015). Two sources were used to identify ALS cases: one database from an ALS medical centre and another from a not-for-profit ALS organization. RESULTS: During this time period, there were 690 incident cases within the two sources. The capture-recapture method estimated 57 unobserved cases, corresponding to a crude five-year incidence rate of 3.29 cases per 100,000 (CI 95%=3.05-3.53). The mean age of diagnosis was 64.6 (CI 95%=59.7-69.4), with 63.5 (CI 95%=56.9-70.1) for men and 65.7 (CI 95%=58.6-72.7) for women. There was a slight male preponderance in incidence, with a 1.05:1 ratio to females. Peak numbers in incidence occurred between the ages of 70 and 79. CONCLUSIONS: The incidence of ALS in BC was found to be consistent with international findings though nominally higher than that in other Canadian provinces to date.


Assuntos
Esclerose Lateral Amiotrófica/epidemiologia , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Colúmbia Britânica/epidemiologia , Criança , Pré-Escolar , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
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