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1.
Tumour Biol ; 37(4): 5305-16, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26561468

RESUMO

Recent research has attempted to direct superantigens towards tumors by means of tumor-targeted superantigen (TTS) strategy. In this study, we explored the antitumor property of TTS by fusing the third loop of transforming growth factor α (TGFαL3) to staphylococcal enterotoxin type B (SEB) and investigated the possibility of the therapeutic application of TGFαL3-SEB as a novel antitumor candidate in mice bearing breast cancer. Treatment was performed through intratumoral and intravenous injection of TGFαL3-SEB. Tumor size/volume, long-term survival, and cytokine secretion were assessed. In addition, the toxicity of each treatment on liver and kidneys was examined. Our results indicated that the relative tumor volume significantly increased in the mice receiving intratumoral TGFaL3-SEB (p < 0.05). Surprisingly, 5 out of the 14 mice were cleared from the tumor thoroughly in 10-25 days after intratumoral administration of TGFaL3-SEB. Quantification of cytokines clearly showed that the mice receiving intratumoral SEB significantly secreted higher interferon γ (IFN-γ) and tumor necrosis factor α (TNF-α) compared with the other groups (p < 0.05). The antitumor effect was followed by inhibition of cell proliferation (Ki-67) and micro vascularization (CD31). The highest and lowest levels of tumor necrosis were observed in the intratumoral administration of TGFαL3-SEB (85 %) and PBS (14 %), respectively. Intratumoral injection of TGFαL3-SEB increased the lifespan of the mice so 37.5 % of them could survive for more than 6 months (p < 0.05). Overall, our findings indicated that intratumoral administration of TGFαL3-SEB effectively inhibited the growth of breast tumors through induction of necrosis and suppressing proliferation and angiogenesis without systemic toxicity.


Assuntos
Neoplasias da Mama/terapia , Proliferação de Células/efeitos dos fármacos , Enterotoxinas/administração & dosagem , Neovascularização Patológica/terapia , Fator de Necrose Tumoral alfa/administração & dosagem , Animais , Neoplasias da Mama/genética , Neoplasias da Mama/imunologia , Enterotoxinas/genética , Enterotoxinas/imunologia , Feminino , Humanos , Imunoterapia/métodos , Interferon gama/metabolismo , Camundongos , Neovascularização Patológica/imunologia , Proteínas de Fusão Oncogênica , Superantígenos/administração & dosagem , Superantígenos/imunologia , Fator de Crescimento Transformador alfa/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia , Ensaios Antitumorais Modelo de Xenoenxerto
2.
Iran J Microbiol ; 16(1): 39-48, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38682061

RESUMO

Background and Objectives: Klebsiella pneumoniae is an opportunistic pathogen responsible for causing nosocomial and community-acquired infections. Its pathogenicity is associated with a variety of virulence factors and antibiotic resistance. The aim of the present study was to compare virulence attributes between ESBL and non-ESBL producing isolates. Materials and Methods: A total of 113 K. pneumoniae including 56 ESBL and 57 non ESBL-producers were collected in Bushehr province, Iran, from November 2017 to February 2019. Enzymatic profile, hypermucoviscosity and biofilm formation were investigated phenotypically. In addition, the presence of rmpA, aerobactin, kfu, allS, mrkD, ybtS, entB, iutA, fimH, wabG, wcaG, K1 and K2 genes were detected by PCR and sequencing. Results: There was no statistically significant difference in enzymatic profile between ESBL and non-ESBL producers. The prevalence of the hypermocoviscosity was lower among ESBL compared to non-ESBL producers but the intensity of biofilm was higher in the ESBL producers. Among the virulence genes, K1, rmpA, iutA, and aero were observed only in non-ESBLs. Moreover, the carriage of allS, K, K2, rmpA, iutA and aero genes was higher in hypermucoviscous in comparison with non hypermucoviscous isolates. Conclusion: The identification of potentially pathogenic isolates plays an important role in preventing their spread as well as the success of their treatment.

3.
Iran J Microbiol ; 15(3): 373-382, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37448670

RESUMO

Background and Objectives: Plasmid-mediated AmpC producers are considered an increasing concern. The aim of this study was to investigate the prevalence of plasmid-mediated AmpC ß-lactamases (pAmpCs) in Klebsiella pneumoniae isolates. Materials and Methods: A total of 228 clinical isolates of K. pneumoniae were collected in Bushehr province, Iran, from December 2017 to February 2019. Cefoxitin disks were applied for screening AmpC-producing isolates. Furthermore, 3 phenotypic confirmatory tests including combine disk test (CDT), double disk synergy test (DDST) and modified three dimensional test (M3DT) were used. Finally, the presence of pAmpC genes was tested by multiplex PCR. Results: We identified 18 pAmpC-KP isolates among the 228 isolates (7.9%): 12 DHA (66.6%) and 6 CMY (33.3%). In the present study only 47% of cefoxitin-resistant isolates were pAmpC producers. The sensitivity of CDT, DDST, and M3DT was 89%, 67% and 100% and the specificity was 90%, 90% and 85%, respectively. In addition, M3DT displayed a higher rate of efficiency (92%) than CDT (89%) and DDST (79%) in detecting plasmid-meditated AmpC producers. Conclusion: DHA was the most prevalent pAmpC beta-lactamase in this study. DDST and CDT tests proved inefficient to detect two and six pAmpC producers, respectively, while M3DT represented the best overall performance.

4.
Iran J Basic Med Sci ; 25(10): 1196-1200, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36311200

RESUMO

Objectives: Production of metallo-ß-lactamases (MBLs) is an important mechanism of resistance to carbapenems. This study aimed to detect the MBL-producing Pseudomonas aeruginosa clinical isolates and to investigate the presence of bla VIM, bla IMP, bla SPM, bla NDM, bla GIM, bla AIM, and bla SIM genes in these isolates in Bushehr, Iran. Materials and Methods: A total of 169 P. aeruginosa clinical isolates were collected from three hospitals in Bushehr. The modified carbapenem inactivation method (mCIM) was used for the phenotypic detection of carbapenemase production. A combination disk test (CDT) was performed for the phenotypic detection of MBL production. To investigate the presence of bla VIM, bla IMP, bla SPM, bla NDM, bla GIM, bla AIM, and bla SIM genes, PCR and sequencing was carried out. Results: Based on the results of mCIM, 40 (23.7%) of 169 isolates were carbapenemase producers. CDT revealed that 26 (15.4%) isolates were MBL producers. bla IMP, bla NDM, and bla VIM genes were found in 18 (69.2%), 8 (30.8%), and 1 (3.8%) of the MBL-producing isolates, respectively. Coexistence of bla IMP and bla NDM was observed in 2 (7.7%) MBL-producing isolates. Among all 169 P. aeruginosa isolates, 23 (13.6%) harbored bla NDM, 18 (10.6%) carried bla IMP, and 1 (0.6%) carried the bla VIM gene. bla SPM, bla GIM, bla AIM, and bla SIM were not found in the present study. Conclusion: bla NDM, bla IMP, and bla VIM genes were detected in this study, which could be a warning sign about the prevalence of these genes among P. aeruginosa clinical isolates in our region. Proper monitoring and detection of MBL-producing isolates are essential steps to prevent the spread of these isolates.

5.
Iran J Microbiol ; 13(2): 161-170, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34540150

RESUMO

BACKGROUND AND OBJECTIVES: Increasing the rate of extended-spectrum ß-lactamase (ESBL)-producing Klebsiella pneumoniae has given rise to a major healthcare issue in clinical settings over the past few years. Treatment of these strains is hardly effective since the plasmid encoding ESBL may also carry other resistance genes including aminoglycosides. The current study aimed to evaluate the prevalence of ESBL-producing K. pneumoniae and investigate the coexistence of Cefoxitamase-Munich (bla CTX-M) with aminoglycoside-modifying enzyme (AME) genes, aac(3)IIa as well as aac(6')Ib, in CTX-M-producing K. pneumoniae isolated from patients in Bushehr province, Iran. MATERIALS AND METHODS: A total of 212 K. pneumoniae isolates were collected and confirmed using polymerase chain reaction (PCR) of the malate dehydrogenase gene. Isolates were screened for production of ESBL. Phenotypic confirmatory test was performed using combined disk test. The genes encoding CTX-M groups and AME genes, aac(3)IIa and aac(6')Ib, were investigated by PCR. RESULTS: The ESBL phenotype was detected in 56 (26.4%) K. pneumoniae isolates. Moreover, 83.9% of ESBL-producing isolates carried the genes for CTX-M type ß-lactamases, which were distributed into the two genetic groups of CTX-M-1 (97.8%)- and CTX-M-2 (2.1%)-related enzymes. Notably, among K. pneumoniae isolates containing the bla CTX-M gene, 68.08% of isolates harbored AME genes. In addition, the coexistence of bla CTX-M with aac(3)-IIa and aac(6')-Ib was observed in 46.8% of CTX-M-producing K. pneumoniae isolates. CONCLUSION: This study provides evidence of a high prevalence of AME genes in CTX-M-producing K. pneumoniae isolates; therefore, in the initial empirical treatment of infections caused by ESBL-KP in regions with such antibiotic resistance patterns, aminoglycoside combination therapy should be undertaken carefully.

6.
Blood Coagul Fibrinolysis ; 32(3): 200-203, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33560003

RESUMO

Coronavirus disease 2019 (COVID-19) is a new medical challenge for all individuals, especially for those with underlying disorders, such as congenital bleeding disorders (CBDs). Therefore, the pandemic might significantly change the behaviour of patients with CBDs and results in some challenges. In the present study, we assessed the main challenges of COVID-19 infection to patients with CBDs. Data were collected from medical files and interviews of patients with CBDs who had COVID-19 infection. Follow-ups were performed on patients who had active severe acute respiratory syndrome coronavirus 2 infection between April and October 2020. All patients were interviewed by an expert in order to collect the pertinent data. Some questions were about patients' preventive behaviors and feelings prior to infection, and some were about the consequences of infection on patients' replacement therapy and bleeding management. Among 25 patients, infection and death of loved ones (n: 7, 28%), and their own (n: 5, 20%) or family members' (n: 1, 4%) infection, and the resulting economic burden (n: 2, 8%) were main concerns. Six patients experienced depression during the pandemic. The pandemic caused all severely affected patients but one (n: 11, 92%) to abandon replacement therapy. However, two received on-demand therapy after exacerbation of their bleeding. Only one (25%) of four patients on prophylaxis received in-home therapy, whereas the others (75%) abandoned prophylaxis. It seems that COVID-19 infection has great consequences on the lives of patients with CBDs, causing some to take dangerous actions, such as abandonment of their treatment. Healthcare systems, and healthcare providers, should have an appropriate strategy for management of patients with CBDs that prevents infection and provides timely replacement therapy.


Assuntos
Transtornos Herdados da Coagulação Sanguínea/complicações , COVID-19/complicações , Adolescente , Adulto , Transtornos Herdados da Coagulação Sanguínea/terapia , COVID-19/sangue , COVID-19/fisiopatologia , COVID-19/psicologia , Bases de Dados Factuais , Depressão/complicações , Feminino , Seguimentos , Hemorragia/prevenção & controle , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários
7.
Technol Cancer Res Treat ; 15(2): 215-26, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25759426

RESUMO

Tumor-targeted superantigens (TTSs) have been used to treat a variety of tumors in preclinical studies. The TTS utilizes the powerful T-cell activation strategy by means of staphylococcal enterotoxins (SEs) as superantigens (Sags) to target tumor cells. Monoclonal antibodies and tumor-related ligands have been used as targeting molecules of Sag. In this study, we assessed the antitumor potency of tumor-targeted superantigen (TTS) strategy to design and produce fusion protein as a new antitumor candidate. The third loop (L3) of transforming growth factor α (TGF-α) was genetically conjugated to staphylococcal enterotoxin type B (TGFαL3-SEB), and its in vitro antitumor activity against murine breast cancer cells (A431 cell line) was evaluated. We designed and prepared TGFαL3-SEB chimeric protein and evaluated superantigenic activity, binding property to cancer cells, overexpression of epidermal growth factor receptor (EGFR), and in vitro antitumor activities. Cloning of tgfαl3-seb was confirmed by colony-polymerase chain reaction, enzymatic digestion, and sequencing. The recombinant TGFαL3-SEB fusion protein with molecular weight of 31 kDa was expressed and confirmed by anti-His Western-blot analysis. The TGFαL3-SEB fusion protein attached to A431 cell line with proper affinity and induced dose-dependent cytotoxicity against EGFR-expressing cancer cells in vitro. The TGFαL3-SEB chimeric protein exhibited potent in vitro antitumor activity. Our findings indicated that TGFαL3-SEB may be a promising anticancer candidate in cancer immunotherapy, and further studies are required to explore its potential in vivo therapeutic applications.


Assuntos
Antineoplásicos/farmacologia , Proteínas Recombinantes de Fusão/farmacologia , Superantígenos/farmacologia , Animais , Antineoplásicos/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Enterotoxinas/genética , Receptores ErbB/metabolismo , Imunoterapia , Concentração Inibidora 50 , Camundongos Endogâmicos BALB C , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética , Staphylococcus aureus/genética , Superantígenos/biossíntese , Fator de Crescimento Transformador alfa/genética
9.
Pathol Res Pract ; 210(12): 836-9, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25238937

RESUMO

Merkel cell polyomavirus (MCPyV), as a new member of polyomaviruses, has recently been discovered as a possible etiologic factor for human cancer. It was first detected in Merkel cell carcinoma (MCC). Small cell lung cancer (SCLC) is a malignant lung tumor which shares histopathological and genetic features with MCC, as both are of neuroendocrine origin. In this study, we investigated the presence of MCPyV DNA in SCLC specimens by real-time PCR. Our null hypothesis was that MCPyV is an etiologic factor in SCLC, as previously seen in MCC. Formalin-fixed and paraffin-embedded (FFPE) specimens were obtained from 50 patients, who underwent bronchoscopic biopsy and were diagnosed with SCLC between March 2010 and March 2012. Similarly, we obtained bronchoscopic biopsy specimens from 29 patients, who were diagnosed with non-small cell lung cancer (NSCLC). All samples were obtained at a single center (Masih Daneshvari Hospital, Tehran, Iran). Real-time PCR was done to detect the presence of MCPyV DNA. After excluding one specimen from the SCLC group due to loss of tumor tissue, we did not detect MCPyV DNA in samples from patients with either SCLC (the mean age 58.9 years, male/female ratio: 7.3/1) or NSCLC. Our results suggest that MCPyV does not play a role in the pathogenesis of SCLC, which is in accord with the results from other prior investigations.


Assuntos
Neoplasias Pulmonares/virologia , Poliomavírus das Células de Merkel/isolamento & purificação , Infecções por Polyomavirus/virologia , Carcinoma de Pequenas Células do Pulmão/virologia , Infecções Tumorais por Vírus/virologia , Idoso , Biópsia , Carcinoma Pulmonar de Células não Pequenas/epidemiologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/virologia , Estudos de Casos e Controles , DNA Viral/genética , DNA Viral/isolamento & purificação , Feminino , Humanos , Irã (Geográfico)/epidemiologia , Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/patologia , Masculino , Poliomavírus das Células de Merkel/genética , Poliomavírus das Células de Merkel/patogenicidade , Pessoa de Meia-Idade , Infecções por Polyomavirus/diagnóstico , Infecções por Polyomavirus/epidemiologia , Valor Preditivo dos Testes , Prevalência , Reação em Cadeia da Polimerase em Tempo Real , Fatores de Risco , Carcinoma de Pequenas Células do Pulmão/epidemiologia , Carcinoma de Pequenas Células do Pulmão/patologia , Infecções Tumorais por Vírus/diagnóstico , Infecções Tumorais por Vírus/epidemiologia
10.
Iran J Cancer Prev ; 7(3): 152-64, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25250167

RESUMO

BACKGROUND: Bacterial superantigen Staphylococcal Enterotoxins (SEs), has stimulated polyclonal T cells irrespective of their antigen specificity, resulted a massive release of cytokines, and suggested that they could be assigned as a candidate of new antitumor agents. Recent attempts have done to specifically target superantigens towards tumors, subsequently Monoclonal antibodies and tumor-related ligands have employed as targeting molecules of superantigen for the preclinical treatment of different tumors. Here, we have evaluated TGFαL3-SEB fusion protein as a new antitumor candidate by genetically fusing the third loop of transforming growth factor alpha (TGFαL3) to Staphylococcal Enterotoxin type B. METHODS: An in silico techniques have launched to characterize the properties and structure of the protein, before initiating the experimental study, we have predicted physicochemical properties, structures, stability, MHC binding properties and ligand-receptor interaction of this chimeric protein by means of computational bioinformatics tools and servers. RESULTS: Our results have indicated codon adaptation index of tgfαl3-seb fusion gene has increased from 0.5 in the wild type sequences to 0.85 in the chimeric optimized gene. The mfold data has shown the tgfαl3-seb mRNA was stable enough for efficient translation in the new host. Based on Ramachandran plot TGFαL3-SEB has classified as a stable fusion protein. Our result has shown fusing of TGFaL3 in N-terminal of the TGFαL3-SEB construct, had no effects on MHC binding and subsequently superantigenic activity of SEB. Finally based on ligand-receptor docking the binding ability of TGFaL3 was strong enough to its receptor, so TGFαL3-SEB could be assigned as a new antitumor candidate in cancer immunotherapy. CONCLUSION: Our results have proposed that TGFαL3-SEB was a stable fusion protein with proper affinity to its receptor that overexpressed in various human carcinomas, so it could generate potent immune response towards tumors.

12.
Nat Prod Commun ; 5(12): 1935-8, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21299124

RESUMO

Antiviral drug resistance is one of the most common problems in medicine, and, therefore, finding new antiviral agents, especially from natural resources, seems to be necessary. This study was designed to assay the antiviral activity of curcumin and its new derivatives like gallium-curcumin and Cu-curcumin on replication of HSV-1 in cell culture. The research was performed as an in vitro study in which the antiviral activity of different concentrations of three substances including curcumin, Gallium-curcumin and Cu-curcumin were tested on HSV-1. The cytotoxicity of the tested compounds was also evaluated on the Vero cell line. The CC50 values for curcumin, gallium-curcumin and Cu-curcumin were 484.2 microg/mL, 255.8 microg/mL and 326.6 microg/mL, respectively, and the respective IC50 values 33.0 microg/mL, 13.9 microg/mL and 23.1 microg/mL. The calculated SI values were 14.6, 18.4 and 14.1, respectively. The results showed that curcumin and its new derivatives have remarkable antiviral effects on HSV-1 in cell culture.


Assuntos
Antivirais/farmacologia , Curcumina/análogos & derivados , Curcumina/farmacologia , Herpesvirus Humano 1/efeitos dos fármacos , Animais , Chlorocebus aethiops , Células Vero
13.
Acta Microbiol Immunol Hung ; 56(1): 89-99, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19388560

RESUMO

This study was conducted at a 900+ bed general teaching hospital, from May to September 2007, in Iran. The aim of this study was to determine the prevalence of extended-spectrum beta-lactamase (ESBL) producing Escherichia coli and Klebsiella pneumoniae and their antimicrobial pattern. The Kirby-Bauer disk diffusion method and the phenotypic disk confirmatory test were performed for each isolate. The total of 206 isolates including 106 E. coli and 100 K. pneumoniae were collected of which 122 isolates (59.2%) were ESBL positive. The prevalence of ESBL-producing strains was 59.2% (122/206). All the isolates were susceptible to imipenem. Among the ESBL-producing isolates, the sensitivity was from 3.3% to 61.5% for ampicillin to aztreonam. From female isolates (136), 59.5% and from male isolates (70), 58.6% were ESBL-producers. Ratios of isolates from hospitalized patients to out-patients were 94/28 in the ESBL-producing group. The number of ESBL-producing isolates according to the isolation sites showed a significant difference between ESBL-producers and non-producers in blood samples (P < 0.05). This study shows that the prevalence of ESBL strains in Iran is high. It seems necessary for clinicians and medical community personnel to be fully aware of ESBL-producing microorganisms.


Assuntos
Infecções por Escherichia coli/epidemiologia , Escherichia coli/classificação , Infecções por Klebsiella/epidemiologia , Klebsiella pneumoniae/classificação , beta-Lactamases/biossíntese , Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/enzimologia , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/microbiologia , Feminino , Hospitais Gerais , Humanos , Imipenem/farmacologia , Irã (Geográfico)/epidemiologia , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/enzimologia , Klebsiella pneumoniae/isolamento & purificação , Masculino , Testes de Sensibilidade Microbiana , Prevalência
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