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1.
Opt Express ; 31(20): 32335-32349, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37859039

RESUMO

We investigate the effect of laser wavelength on laser-induced breakdown spectroscopy (LIBS) on the measurement of carbon in agricultural soils. Two laser wavelengths, 1064 nm and 532 nm, were used to determine soil carbon concentration. No chemical pretreatment, grinding, or pelletization was performed on soil samples to simulate in-field conditions. A multivariate calibration model with outlier filtering and optimized parameters in partial least squared regression (PLSR) was established and validated. The calibration model estimated carbon content in soils with an average prediction error of 4.7% at a laser wavelength of 1064 nm and 2.7% at 532 nm. The limit of detection (LOD) range for 532 nm was 0.34-0.5 w/w%, approximately half of the LOD range for 1064 nm laser wavelength. The improvement in prediction error and LOD of LIBS measurements is attributed to the increase in plasma density achieved at 532 nm.

2.
Breast Dis ; 41(1): 229-239, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35404268

RESUMO

BACKGROUND: The presence of human cytomegalovirus (HCMV) in breast cancer has been reported, suggesting a potential association between HCMV infection and breast carcinogenesis. OBJECTIVE: To evaluate the association between HCMV infection and immune activation and inflammatory markers in breast cancer. METHODS: HCMV DNA was detected from all patients using real-time PCR, Anti HCMV IgM and IgG antibodies were measured. IL-17 and IL-22 concentrations were detected by ELISA. Assessment of NLR and PLR was done, and cell proliferation was assessed using MTT assay. RESULTS: The results revealed a significantly increased prevalence of anti-HCMV IgG and HCMV DNA in patients compared to both benign and control groups where positive HCMV prevalence was significantly associated with vascular invasion, proliferation rate, high neutrophil-to-lymphocyte ratio (NLR), and elevated IL-17 serum level. Furthermore, we demonstrated that increased serum IL-17 in patients was markedly associated with tumor stage, vascular invasion, and high NLR. CONCLUSION: It can be concluded that HCMV infection may have vital roles in breast cancer pathogenesis. Moreover, altered peripheral blood cells and cytokines may result in disordered immune response in breast cancer patients.


Assuntos
Infecções por Citomegalovirus , Neoplasias Inflamatórias Mamárias , Anticorpos Antivirais/sangue , Biomarcadores/sangue , Citomegalovirus , Infecções por Citomegalovirus/complicações , Infecções por Citomegalovirus/epidemiologia , Humanos , Imunoglobulina G/sangue , Inflamação/complicações , Neoplasias Inflamatórias Mamárias/imunologia , Neoplasias Inflamatórias Mamárias/virologia , Interleucina-17/sangue
3.
Microbiol Immunol ; 65(9): 392-399, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34081342

RESUMO

Lupus nephritis (LN) is one of the most serious complications of systemic lupus erythematosus (SLE). Multiple immunomodulatory mechanisms contribute to the pathogenesis of LN. A deep understanding of the immunopathogenesis of LN is essential to identify optimal molecular targets, as most immunotherapeutic algorithms are still based on unselective drugs. The study aimed to elucidate the possible association of vitamin D deficiency with the programmed death-1 (PD-1)/programmed death ligand-1 (PD-L1) axis and inflammatory response in patients with LN, as well as the relationship between the PD-1/PD-L1 axis and chemokine C-X-C motif ligand 12 (CXCL12). Flow cytometry was used to determine the frequencies of CD279 (PD-1) and CD274 (PD-L1) in the peripheral CD3+CD4+ cell population of persons with LN. Furthermore, ELISA was used to detect serum CXCL12 and vitamin D concentrations. A distinct decrease of PD-1 and a significant increase of PD-L1 was demonstrated in patients with LN compared with either SLE patients with no LN or healthy controls. The PD-1/PD-L1 axis was negatively correlated with different disease parameters. Vitamin D deficiency and insufficiency were more prevalent in patients with LN than in controls, being significantly associated with disease activity and inversely associated with the PD-1/PD-L1 expression. Moreover, CXCL12 was negatively correlated with the PD-1/PD-L1 axis and vitamin D concentration. The findings suggest an involvement of the PD-1/PD-L1 axis in lupus nephritis, which might serve as a potential highly selective therapeutic target that is more effective but less toxic. In addition, restoring adequate vitamin D levels in lupus nephritis could be a possible simple measure to control inflammatory immune responses.


Assuntos
Antígeno B7-H1 , Linfócitos T CD4-Positivos , Quimiocina CXCL12 , Nefrite Lúpica , Humanos , Imunidade , Receptor de Morte Celular Programada 1 , Vitamina D
4.
Dev Biol ; 475: 118-130, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33705737

RESUMO

The lysine methyltransferase NSD3 is required for the expression of key neural crest transcription factors and the migration of neural crest cells. Nevertheless, a complete view of the genes dependent upon NSD3 for expression and the developmental processes impacted by NSD3 in the neural crest was lacking. We used RNA sequencing (RNA-seq) to profile transcripts differentially expressed after NSD3 knockdown in chick premigratory neural crest cells, identifying 674 genes. Gene Ontology and gene set enrichment analyses further support a requirement for NSD3 during neural crest development and show that NSD3 knockdown also upregulates ribosome biogenesis. To validate our results, we selected three genes not previously associated with neural crest development, Astrotactin 1 (Astn1), Dispatched 3 (Disp3), and Tropomyosin 1 (Tpm1). Using whole mount in situ hybridization, we show that premigratory neural crest cells express these genes and that NSD3 knockdown downregulates (Astn1 and Disp3) and upregulates (Tpm1) their expression, consistent with RNA-seq results. Altogether, this study identifies novel putative regulators of neural crest development and provides insight into the transcriptional consequences of NSD3 in the neural crest, with implications for cancer.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento/genética , Histona-Lisina N-Metiltransferase/metabolismo , Crista Neural/fisiologia , Animais , Embrião de Galinha , Expressão Gênica/genética , Perfilação da Expressão Gênica/métodos , Redes Reguladoras de Genes/genética , Histona-Lisina N-Metiltransferase/genética , Hibridização In Situ/métodos , Crista Neural/embriologia , Crista Neural/metabolismo , Análise de Sequência de RNA/métodos , Fatores de Transcrição/metabolismo
5.
Egypt J Immunol ; 15(1): 181-92, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-20306682

RESUMO

UNLABELLED: Accumulation of malignant B-lymphocytes in chronic B-cell lymphocytic leukemia (B-CLL) is mainly attributed to reduced apoptosis rather than increased proliferation rate. Interleukin-4 (IL-4) has been proved to be involved in the survival mechanisms of B-cells as well as protection of B-CLL cells against spontaneous or drug induced apoptosis. Fludarabine is one of purine analogs and the current standard treatment for B-CLL, which has been proved to induce apoptosis in normal and malignant lymphocytes. We investigated the effect of ex vivo treatment of peripheral blood lymphocytes (PBLs) with Fludarabine on apoptosis and IL-4 production in untreated patients with B-CLL. The study was conducted on 15 recently diagnosed B-CLL patients and 15 normal healthy control subjects. PBLs were isolated and cultured in complete culture media without and with the addition of 1 microM/ml Fludarabine for 48 hrs. Harvested cells were assessed by flowcytometry for apoptosis and IL-4 production using staining with Annexin-V/PI and specific monoclonal IL-4 antibody, respectively. RESULTS: Fludarabine significantly increased the rate of in vitro PBLs' apoptosis in both B-CLL patients and normal subjects (3.81 +/- 1.98% and 4.11 +/- 2.14% without Fludarabine vs 14.78 +/- 7.83% and 9.99 +/- 5.60% with Fludarabine, respectively). However, the cytotoxic effect of Fludarabine was significantly higher in B-CLL patients than normal control subjects. Cytolasmic IL-4 content, as reflected by mean flouresence intensity (MFI), as well as percentage of IL-4+ve PBLs in absence Fludarabine were nearly the same both in B-CLL patients (20.28 +/- 14.34 & 2.97 +/- 1.48%, respectively) and normal subjects (27.75 +/- 14.44 & 2.58 +/- 1.27% respectively), with no significant difference. Corresponding values were significantly increased in both B-CLL patients (34.46 +/- 22.95 & 15.08 +/- 8.17%, respectively) and normal subjects (40.15 +/- 17.11 & 17.05 +/- 8.74%, respectively) when PBLs were co-cultured with Fludarabine. However, no significant difference was observed when studied groups were compared to each other. No correlation was observed between the intracellular IL-4 content or percentage of IL-4+ve PBLs and Fludarabine-induced apoptosis. In conclusion, Floudarabine could induce apoptosis and IL-4 production in B-CLL patients. Further studies on large cohort population is recommended to clarify the apoptotic effect of Fludarabine.


Assuntos
Apoptose/efeitos dos fármacos , Interleucina-4/metabolismo , Leucemia Linfocítica Crônica de Células B/metabolismo , Leucemia Linfocítica Crônica de Células B/patologia , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/patologia , Vidarabina/análogos & derivados , Idoso , Feminino , Hemoglobinas/análise , Humanos , Leucemia Linfocítica Crônica de Células B/sangue , Leucemia Linfocítica Crônica de Células B/diagnóstico , Contagem de Leucócitos , Leucócitos Mononucleares/efeitos dos fármacos , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Contagem de Plaquetas , Vidarabina/farmacologia
6.
Egypt J Immunol ; 10(1): 47-56, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-15719622

RESUMO

Telomerase is a ribonucloprotein enzyme that appears to play a role in carcinogenesis. To understand the regulatory mechanisms which govern telomerase activity, we used telomeric repeat amplification protocol (TRAP) to quantitate and compare telomerase activity in cultured peripheral blood mononuclear cells (PBMCs) with and without INF-gamma in breast cancer patients. Serum levels of IFN-gamma and vitamin-A were also measured to look for a possible influence of these chemotherapeutic agents on telomerase activity. 23 premenopausal breast carcinoma patients (8 with clinical stage 11, 8 stage III and 7 stage IV) and ten age and menstrual stage matched healthy controls were studied. Before surgery, telomerase activity and IFN-gamma levels were significantly higher (P<0.001, P<0.05 respectively) in patients than controls and were associated with significant lower (P<0.001) serum level of vitamin-A. After surgery, chemotherapy for 3 cycles and oral vitamin-A, a sharp reduction in telomerase activity and serum IFN-gamma levels was observed in all groups of patients compared to the controls. Cultivation of PBMCs in the presence of IFN-gamma caused up-regulation (about 25%) of telomerase activity. However, a significant positive correlation (r = 0.941; P < 0.001) in telomerase activity was observed between cultured PBMCs with and without IFN-gamma in all breast cancer patients before treatment. Positive correlation was also found between serum levels of IFN-gamma and telomerase activity of cultured PBMCs with and without IFN-gamma (P< 0.01). In contrast, negative correlations were observed between serum levels of vitamin-A and telomerase activity and serum levels of IFN-gamma (P < 0.01). It is concluded that IFN-gamma and vitamin-A may modulate telomerase activity in breast cancer patients and this should be considered in developing new strategies to control cancer cell growth.


Assuntos
Neoplasias da Mama/enzimologia , Neoplasias da Mama/imunologia , Interferon gama/sangue , Telomerase/sangue , Vitamina A/sangue , Adulto , Neoplasias da Mama/sangue , Estudos de Casos e Controles , Células Cultivadas , Feminino , Humanos , Interferon gama/antagonistas & inibidores , Leucócitos Mononucleares/enzimologia , Leucócitos Mononucleares/imunologia , Pessoa de Meia-Idade
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