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1.
Iran J Microbiol ; 15(4): 585-593, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38045712

RESUMEN

Background and Objectives: Breast cancer is currently the most commonly diagnosed neoplasm in women worldwide. There is evidence that human papillomavirus (HPV) infection may play a key role in breast cancer aggressiveness, but results are conflicting across studies. The aim of this study was to investigate the presence of the HPV viral genome in benign and malignant breast tissue samples and its clinicopathological characteristics of cancer. Materials and Methods: In this case-control study, 100 formalin-fixed paraffin-embedded (FFPE) of breast cancer and 100 blocks of non-cancerous breast tissue were selected as a control group from the pathology department of Imam Khomeini Hospital in Ahvaz from 2020-2022. The presence of HPV was detected using nested PCR including MY09/11 primers and sequencing were performed for virus genotyping. Results: The present study enrolled 100 subjects each in two cancer and control groups with a mean age of 52.81±13.23 and 35.77±11.65, respectively. The risk of cancer in HPV-infected patients is almost 5 times higher than in HPV-negative individuals, it is not statistically significant (OR =4.99, 95% CI 0.35 to 72.15, p=0.238). The prevalence of HPV in the cancer and control groups was 7% and 1%, respectively and HPVs detected in two groups were of the HPV 16 genotype. Although the chance of ER and PR expression, lymphvascular involvement, perineural invasion, and higher tumor grade was higher in HPV-positive subjects than in HPV-negative subjects, this was not statistically significant (OR>1, p>0.05). Conclusion: Based on studies reporting the existence of sequences of different high-risk HPV types (oncogenes) in breast cancer tissues, this study confirmed the hypothesis of a possible infectious cause in the development of breast cancer. So far, however, the results have been controversial and inconclusive. Further studies with large sample sizes are needed to demonstrate the link between HPV and breast cancer.

2.
Asian Pac J Cancer Prev ; 23(11): 3931-3937, 2022 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-36444607

RESUMEN

BACKGROUND: Head and neck squamous cell carcinoma is one of the most important malignancies, worldwide. Oncogenic viruses, such as human papilloma virus (HPV) and Epstein-Barr virus (EBV), are linked to these cancers and studies suggest a possible interaction between HPV and EBV during co-infections to promote oncogenesis. Nonetheless, these reports are controversial and demand more investigations in this regard. The present work to assessed the prevalence of HPV and co-infection with EBV in oral and oropharyngeal squamous cell carcinomas. METHODS: Formalin-fixed paraffin-embedded tissues were collected from 166 archived oral and oropharyngeal squamous cell carcinoma samples from Ahvaz Imam Khomeini hospital, Ahvaz, Iran, from March 2013 and December 2019. Nested-PCR was used to detect the viruses and type-specific PCR/nested-PCR and sequencing were performed for virus genotyping. RESULTS: Out of the 166 specimens, 84.33% and 16.42% were from oral cavity and oropharynx, respectively; of which, 32 cases (19.3%) were HPV-positive (16.42% of oral cavity and 34.6% of oropharynx). HPV was detected in 36.36%, 25%, and 16.42% of base of tongue, tonsil, and oral tongue tumors, respectively. HPV was more associated with well differentiated tumors (24;18.04%) in compared to moderately and poorly differentiated ones. Regarding HPV-16 genotyping, 7 (21.8%) out of the 32 samples were found to be HPV-16 (4/26 (15.38%) for oropharynx and 3/140 (2.14%) for oral cavity). Moreover, 90 samples were evaluated for EBV infection and co-infection; of which, 4 (4.4%) subjects tested positive for EBV, including two cases with HPV co-infection. All the positive cases were EBV type B, from oral cavity, and histologically well differentiated. CONCLUSIONS: HPV was more associated with oropharyngeal cancer. This association has been linked to various factors such as repeated oral and oropharyngeal exposure to HPV due to change in patterns of sexual behaviors; a phenomenon that may demand routine HPV vaccination.


Asunto(s)
Alphapapillomavirus , Coinfección , Infecciones por Virus de Epstein-Barr , Neoplasias de Cabeza y Cuello , Neoplasias de la Boca , Infecciones por Papillomavirus , Humanos , Papillomaviridae/genética , Herpesvirus Humano 4/genética , Carcinoma de Células Escamosas de Cabeza y Cuello/epidemiología , Coinfección/epidemiología , Prevalencia , Infecciones por Virus de Epstein-Barr/complicaciones , Infecciones por Virus de Epstein-Barr/epidemiología , Infecciones por Papillomavirus/complicaciones , Infecciones por Papillomavirus/epidemiología , Neoplasias de la Boca/epidemiología
3.
Asian Pac J Cancer Prev ; 22(9): 2939-2944, 2021 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-34582665

RESUMEN

BACKGROUND: Hepatitis B virus (HBV) is an important public health problem worldwide. Chronic HBV in patients undergoing chemotherapy and immunosuppressive treatment are at risk of HBV reactivation. The consequence of HBV reactivation in immunosuppressed patients may lead to liver failure and death. Therefore, this study was conducted to investigate the frequency of HBV markers in cancer patients before chemotherapy. MATERIALS AND METHODS: In this study cross-sectional, blood samples were collected from 90 cancer patients before chemotherapy. The patient's sera were tested for the presence of HBsAg and anti-HBc using enzyme-linked immunosorbent assay (ELISA). The HBVDNA was tested for patient's sera using nested polymerase chain reaction (nested-PCR). RESULTS: Among 90 patients, 42(46.7%) were males and 48 (53.3%) females, with a mean age of 52.52 ± 11.71 years (range, 25-83 years). Of the 6/90 (6.66%)  patients, including 4/42 (9.5%) males and 2/48 (4.1%) females cases were positive for HBsAg,  anti-HBc and HBV DNA, (P=0.31).  The frequency of HBV infection in cancer patients  was rectal 3(3.33%),  breast cancer  2 (2.22%) and prostate 1(1.11%) cases. The sera of 8/84 (9.52%) patients including 5/39 (12.82%) males and 3/45 (6.66%) females tested positive for anti-HBc, but negative for HBsAg and HBV DNA. (P=0.55). The results of phylogenetic tree revealed that  four isolated HBV DNA in cancer patients were cluster with genotype D. CONCLUSIONS: High frequency of 6.66%  HBV infection have been observed in cancer patients before chemotherapy. The sera of  9.52% patients were only positive for anti-HBc IgG which may indicate the past HBV infection or presence of OBI but requires further investigation. To prevent HBV or OBI reactivation, the screening of HBV DNA and anti HBc should be implemented for cancers patients before chemotherapy.


Asunto(s)
Hepatitis B/epidemiología , Neoplasias/tratamiento farmacológico , Neoplasias/virología , Adulto , Anciano , Anciano de 80 o más Años , Estudios Transversales , ADN Viral/sangre , Ensayo de Inmunoadsorción Enzimática , Femenino , Anticuerpos contra la Hepatitis B/sangre , Antígenos de Superficie de la Hepatitis B/sangre , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/inmunología , Virus de la Hepatitis B/aislamiento & purificación , Humanos , Masculino , Persona de Mediana Edad , Filogenia , Reacción en Cadena de la Polimerasa
4.
Ther Apher Dial ; 25(2): 218-224, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32510846

RESUMEN

The aim of this study was to investigate the prevalence of occult hepatitis C virus (HCV) infection (OCI) among HD patients. Blood samples were taken from 79 HD patients and their sera were evaluated for the presence of anti-HCV. Both the sera and peripheral blood mononuclear cells (PBMCs) were then checked for HCV RNA by nested reverse transcriptase-polymerase chain reaction. Anti-HCV was positive among 4/79 (5.1%) of the patients. From 75 patients who were negative for anti-HCV, 71 (94.7%) patients were also negative for HCV RNA in sera samples but five of them were positive for HCV RNA in PBMCs. Totally, out of 79 patients, HCV RNA was detected in PBMCs of five (6.3%) patients, indicating that these patients had OCI. No significant difference was observed between the frequency of OCI and gender (P-value = .6). HCV genotype in all five cases of OCI was genotype 3a. Our study showed prevalence rate of 6.3% OCI infection in HD patients. Regarding the serious complications and the clinical importance of OCI in HD patients, sensitive diagnostic methods for identifying HCV RNA in the PBMCs should be implemented for all HD patients.


Asunto(s)
Hepacivirus/aislamiento & purificación , Hepatitis C/diagnóstico , ARN Viral/sangre , Diálisis Renal , Adulto , Anciano , Anciano de 80 o más Años , Estudios Transversales , Femenino , Genotipo , Hepacivirus/genética , Hepatitis C/sangre , Hepatitis C/epidemiología , Humanos , Leucocitos Mononucleares/virología , Masculino , Persona de Mediana Edad , Prevalencia , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Pruebas Serológicas/métodos , Adulto Joven
5.
Food Sci Nutr ; 8(3): 1383-1393, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32180948

RESUMEN

In this study, oil extraction from Niger seeds was evaluated with different microwave irradiation times (0-200 s) and pulsed electric fields (PEF) intensities (0-5 kV/cm) as pretreatments. Then, oil extraction was completed with a screw press at different rotation speeds (11-57 rpm). Quality parameters including extraction efficiency, acidity and peroxide values (PVs), chlorophyll, and phenolic contents along with fatty acid profiles and tocopherol levels of the extracted oils were determined as responses. With enhancements in microwave time, PEF intensity and press rotation, the chlorophyll contents, acidity/PVs, and total phenolics of oils increased similar to oil extraction efficiency although it was reduced later. The optimized conditions selected by response surface methodology were determined as 156.23 s, 1.18 kV/cm, and 20 rpm for microwave time, PEF intensity and press speed, respectively. Fatty acid analysis revealed that linoleic acid was the most predominant fatty acid in the extracted oil. Application of the mentioned pretreatments may lead to a reduction in unsaturated fatty acids and escalation of saturated ones (p < .05). High-performance liquid chromatography results indicated that α-tocopherols are the most common tocopherols in Niger seed oil and microwave-PEF pretreatments may lead to 2.79% increase in tocopherols content.

6.
Rev Med Virol ; 30(1): e2088, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31788897

RESUMEN

Cancer progression is critically associated with modulation of host cell signaling pathways. Activator protein-1 (AP-1) signaling is one such pathway whose deregulation renders the host more susceptible to cancer development. Oncogenic viruses, including hepatitis B virus, hepatitis C virus, human papilloma virus, Epstein-Barr virus, human T-cell lymphotropic virus type 1, and Kaposi's sarcoma-associated herpes virus, are common causes of cancer. This review discusses how these oncoviruses by acting through various aspects of the host cell signaling machinery such as the AP-1 pathway might affect oncoviral tumorigenesis, replication, and pathogenesis. The review also briefly considers how the pathway might be targeted during infections with these oncogenic viruses.


Asunto(s)
Transformación Celular Viral , Neoplasias/etiología , Neoplasias/metabolismo , Virus Oncogénicos/fisiología , Transducción de Señal , Factor de Transcripción AP-1/metabolismo , Infecciones Tumorales por Virus/complicaciones , Infecciones Tumorales por Virus/virología , Animales , Susceptibilidad a Enfermedades , Interacciones Huésped-Patógeno , Humanos , Neoplasias/patología
7.
Rev Med Virol ; 30(1): e2085, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31743548

RESUMEN

Oncogenic viruses are one of the most important causes of cancer worldwide. The pathogens contribute to the establishment of human malignancies by affecting various cellular events. Epigenetic mechanisms, such as histone modification methylation/demethylation, are one of the most critical events manipulated by oncogenic viruses to drive tumorigenesis. Histone modifications are mediated by histone acetylation and deacetylation, regulated by histone acetyltransferases (HATs) and histone deacetylases (HDACs), respectively. Dysregulation of HDACs activity affects viral tumorigenesis in several ways, such as manipulating tumor suppressor and viral gene expression. The present review aims to describe the vital interactions between both cancer-caused/associated viruses and the HDAC machinery, particularly by focusing on those viruses involved in gastrointestinal tumors, as some of the most common viral-mediated cancers.


Asunto(s)
Transformación Celular Viral , Susceptibilidad a Enfermedades , Histona Desacetilasas/metabolismo , Interacciones Huésped-Patógeno , Neoplasias/etiología , Neoplasias/metabolismo , Animales , Regulación de la Expresión Génica , Histona Acetiltransferasas/metabolismo , Humanos , Neoplasias/patología , Virus Oncogénicos/fisiología , Infecciones Tumorales por Virus/complicaciones , Infecciones Tumorales por Virus/virología
8.
Iran J Parasitol ; 14(4): 584-591, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-32099561

RESUMEN

BACKGROUND: This study was conducted to determine the presence and molecular identify of Acanthamoeba, Naegleria and Vermamoeba in unimproved hot springs. METHODS: From Jul to Aug 2017, 54 water samples were collected from hot springs in different parts of the Guilan Province, North Iran. For the isolation of Acanthamoeba, Naegleria and Vermamoeba approximately 500 ml of the water samples were filtered through a cellulose nitrate membrane with a pore size of 0.45 µm. The filter was transferred onto non-nutrient agar plates seeded with Gram-negative bacteria (Escherichia coli) as a food source. The morphological key of page was used to identify free-living amoebae (FLA) using an inverted microscope, PCR amplification targeting specific genes for each genus and sequencing determined frequent species and genotypes base on NCBI database. RESULTS: Fifteen of the 54 samples were positive by culture and/or PCR for Acanthamoeba and other FLA from unimproved hot springs. By sequencing the positive isolates, the strains were shown to belong to Acanthamoeba castellanii (12 case isolates belonged to T4 genotype), 4 cases of V. vermiformis, and 3 cases of N. australiensis, 2 cases of N. pagei and 1 cases of N. gruberi. CONCLUSION: Although FLA-mediated illnesses are not as high as in environmental distribution, but because of a poor prognosis, more investigations about FLA distribution in hot springs is critical. Hot spring may enhance exposure of the amoebae in individuals. Hence, more attention to unimproved hot springs is needed to prevent free-living amoebae mediated diseases.

9.
Biomed Pharmacother ; 105: 1353-1359, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30021373

RESUMEN

Drug resistance is still the major threat to global tuberculosis (TB) control, and drug-resistant (DR) Mycobacterium tuberculosis (M. tuberculosis) strains have become the main challenge worldwide. Currently used antibiotics for treatment of DR-TB are often poorly tolerated and not sufficiently effective. Since the therapeutic options are still limited, the main strategy for treatment of DR-TB is to repurpose existing anti-mycobacterial agents. Clofazimine (CFZ) is one such drug that has recently attracted interest against DR-TB. CFZ is a hydrophobic riminophenazine that was initially synthesized as an anti-TB antibiotic. Although the mechanisms of action of CFZ are not yet entirely understood, it has been suggested that outer membrane is its primary action site, and the respiratory chain and ion transporters are the putative targets. In this review, we will discuss the anti-mycobacterial properties of CFZ, and provide new insights into the clinical use of this drug.


Asunto(s)
Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Antituberculosos/farmacología , Antituberculosos/uso terapéutico , Clofazimina/farmacología , Clofazimina/uso terapéutico , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológico , Animales , Humanos , Mycobacterium tuberculosis/efectos de los fármacos
10.
Arch Iran Med ; 21(3): 101-110, 2018 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-29688735

RESUMEN

BACKGROUND: This study aimed to evaluate Rabies virus vaccine strains. The obtained results may be helpful for vaccine producers and researchers to compare the strains with wild type and other vaccine strains and select the correct strain to challenge their products. METHODS: Fourteen rabies virus vaccine strains were compared with each other. The full genomes of the selected strains were taken from the GenBank and the N, P and G genes were labeled. The major and minor antigenic sites of these sequences were identified and contrasted with each other. The identity matrix was designed for rabies virus full genome, N and G genes. In addition, the phylogenetic tree was drawn based on rabies virus N gene for deep analysis. RESULTS: Although there were no significant differences between antigenic sites in N, P, and G genes, there were noticeable differences for full genome identity matrix and this significant difference can also be observed in N and G identity matrix. In the phylogenetic tree, the Iranian sequences were distant from currently applied vaccine strains. CONCLUSION: It is necessary to pay attention to the results shown in phylogenetic tree because they warn us about distance between the Iranian sequences and current strains used in applied vaccines. In addition, the obtained results help vaccine producers to choose a correct strain to challenge their product and evaluate their vaccine potency.


Asunto(s)
Genoma Viral , Filogenia , Vacunas Antirrábicas/genética , Virus de la Rabia/clasificación , Irán , Rabia/prevención & control , Análisis de Secuencia
11.
Food Sci Nutr ; 6(1): 111-118, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29387368

RESUMEN

Application of novel technologies such as microwave and pulsed electric fields (PEF) might increase the speed and efficiency of oil extraction. In the present research, PEF (3.25 kV/cm electric field intensity and 30 pulse number) and microwave (540 W for 180 s) pretreatments were used to study the process of oil extraction from black cumin (Nigella sativa) seeds. After applying the selected pretreatments, the oil of seeds was extracted with the use of a screw press and the extraction efficiency, refractive index, oil density, color index, oxidative stability, and chemical components of oil and protein of meal were evaluated. The achieved results expressed that PEF and microwave pretreatments increased the oil extraction efficiency and its oxidative stability. Different pretreatments didn't have any significant influence on the refractive index of black cumin seed oil (p>.05). When microwave and PEF were used, the oil density showed an enhancement as the following: 1.51% and 0.96%, respectively in comparison with the samples with no pretreatments. Evaluation of the extracted oils, using GC/MS analysis indicated that thymoquinone was the dominant phenolic component in the black cumin oil. Finally, the SEM analysis revealed that microwave and PEF can be useful in the extraction of oil from black cumin seeds since these treatments damaged cell walls and facilitated the oil extraction process.

12.
Rev Med Virol ; 28(2)2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29345394

RESUMEN

Transforming growth factor-ß (TGF-ß) signaling pathway is a key network in cell signaling that controls vital processes such as proliferation, differentiation, apoptosis, epithelial-mesenchymal transition, and migration, thus acting as a double-edged sword in normal development and diseases, in particular organ fibrosis, vascular disorders, and cancer. Early in tumorigenesis, the pathway exerts anti-tumor effects through suppressing cell cycle and inducing apoptosis, while during late stages, it functions as a tumor promoter by enhancing tumor invasiveness and metastasis. This signaling pathway can be perturbed by environmental and genetic factors such as microbial interference and mutation, respectively. In this way, the present review describes the modulation of the TGF-ß pathway by oncogenic human viral pathogens and other viruses. The main mechanisms by which viruses interferes with TGF-ß signaling seems to be through (1) the alteration of either TGF-ß protein expression or activation, (2) the modulation of the TGF-ß receptors or SMADs factors (by interfering with their levels and functions), (3) the alteration of none-SMAD pathways, and (4) indirect interaction with the pathway by the modulation of transcriptional co-activator/repressor and regulators of the pathway. Given the axial role of this pathway in tumorigenesis, it can be regarded as an attractive target for cancer therapy. Hence, further investigations on this subject may represent molecular targets among either TGF-ß signaling molecules or viral factors for the treatment and management of viral infection consequences such as cancer.


Asunto(s)
Interacciones Huésped-Patógeno , Neoplasias/etiología , Neoplasias/metabolismo , Transducción de Señal , Factor de Crecimiento Transformador beta/metabolismo , Fenómenos Fisiológicos de los Virus , Animales , Transformación Celular Viral , Humanos , Virus Oncogénicos/fisiología , Infecciones Tumorales por Virus/complicaciones , Infecciones Tumorales por Virus/virología
13.
Int J Biol Macromol ; 111: 1091-1099, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29366896

RESUMEN

The main goal of this study was to prepare bionanocomposites by combination of gelatin (10% w/v), k-carrageenan (0.5%) and nano-SiO2 (1, 3 or 5%). Then, mechanical properties (tensile strength, elongation at break, Young's modulus), gas permeability (water vapor, oxygen), water solubility, color, UV-vis transmission/absorbance, water vapor adsorption isotherms and Fourier transform infrared (FTIR) analysis of nanocomposites were evaluated. As the results indicated, inclusion of nano-SiO2 (at each level) could increase tensile strength and Young's modulus significantly, with the latter becoming nearly 110% higher at 5% nanoparticle level compared with gelatin-carrageenan biocompostes. Furthermore, incorporation of 5% nano-SiO2 could decrease water vapor permeability of biocomposites from 8.9 to 1.6 × 10-11 g m-1 s-1 Pa-1 and their oxygen permeability from 226 to 97 cm3 µm m-2 day-1 atm-1. Water vapor adsorption isotherms revealed that the water activity of 0.5 was the critical point beyond which the difference in equilibrium moisture content between nanoparticle-incorporated films and biocomposites increased considerably. Besides, this research demonstrated that including 5% of nano-SiO2 is a good solution to delay UV light driven reactions as it elevated absorbance of UV light (220 nm) by biocomposites up to 4 times.


Asunto(s)
Carragenina/química , Gelatina/química , Nanocompuestos/química , Adsorción , Dióxido de Silicio/química , Espectroscopía Infrarroja por Transformada de Fourier , Resistencia a la Tracción , Rayos Ultravioleta , Agua/química
14.
J Cell Physiol ; 233(5): 4000-4014, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-28926109

RESUMEN

Gastrointestinal cancers are a global public health problem, which represent a vast majority of all cancer-caused deaths in both men and women. On the other hand, viral pathogens have been long implicated as etiological factors in the onset of certain human cancers, including gastrointestinal tumors. In this regard, Human Papilloma Virus (HPV), Epstein-Barr Virus (EBV), and John Cunningham Virus (JCV) have been more strongly suggested to be involved in gastrointestinal carcinogenesis; so that, the association of HPV with oropharyngeal and anal cancers and also the association of EBV with gastric cancer have been etiologically confirmed by epidemiological and experimental investigations. Although, the association of other viruses is less evident, but may rely on co-factors for their oncogenic roles. Therefore, to improve the prevention and treatment of these classes of cancer, their association with viral agents as potential risk factors should be investigated with care. In this respect, the present review has focused on the existing literature on the subject of viral involvement in gastrointestinal tumorgenesis, by covering and discussing various gastrointestinal cancers, corresponding viral agents and their oncogenic aspects and then summarizing evidences either supporting or rejecting a causal role of these pathogens in gastrointestinal malignancies.


Asunto(s)
Carcinogénesis/genética , Neoplasias Gastrointestinales/virología , Neoplasias Gastrointestinales/genética , Neoplasias Gastrointestinales/patología , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/patogenicidad , Humanos , Virus JC/genética , Virus JC/patogenicidad , Papillomaviridae/genética , Papillomaviridae/patogenicidad
15.
Biomed Pharmacother ; 94: 982-994, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28810536

RESUMEN

Urinary tract infection(UTI) caused by Gram-negative bacteria is the second most common infectious presentation in community medical practice. Approximately 150 million people are diagnosed with UTI each year worldwide. Drug resistance in Gram-negative uropathogens is a major global concern which can lead to poor clinical outcomes including treatment failure, development of bacteremia, requirement for intravenous therapy, hospitalization, and extended length of hospital stay. The mechanisms of drug resistance in these bacteria are important due to they are often not identified by routine susceptibility tests and have an exceptional potential for outbreaks. Treatment of UTIs depends on the access to effective drugs, which is now threatened by antibiotic resistant Gram-negative uropathogens. Although several effective antibiotics with activity against highly resistant Gram-negatives are available, there is not a unique antibiotic with activity against the high variety of resistance. Therefore, antimicrobial susceptibility tests, correlation between clinicians and laboratories, development of more rapid diagnostic methods, and continuous monitoring of drug resistance are urgent priorities. In this review, we will discuss about the current global status of drug-resistant Gram-negative uropathogens and their mechanisms of drug resistance to provide new insights into their treatment options.


Asunto(s)
Farmacorresistencia Bacteriana/efectos de los fármacos , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Gramnegativas/patogenicidad , Animales , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Humanos , Infecciones Urinarias/tratamiento farmacológico , Infecciones Urinarias/microbiología
16.
Microb Pathog ; 109: 209-213, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28579398

RESUMEN

Human respiratory syncytial virus (RSV) is a leading cause of acute respiratory infection during early childhood and imposes a great burden on patients, parents, and society. Disease is thought to be caused, at least partially, by an excessive immune response. Pulmonary leukocyte infiltration is the result of a coordinated expression of diverse chemokines with distinct cellular specificities. Lipoxygenases (LOXs), as a key enzyme catalyzing deoxygenation of poly unsaturated fatty acids, regulate inflammation and have been suggested to play an important role in the immune response in viral infection. To expand our understanding on the possible role of LOX in respiratory viral infection, we studied the 12/15- lipoxygenase expression in RSV-related airway inflammation, and the related inflammatory chemokines, Chemokine (C-C motif) ligand 5 (CCL5) and Chemokine (C-C motif) ligand 3(CC L3) in both lung tissue and Bronchoalveolar lavage (BAL) fluid during experimental RSV infection. RSV infection induced mRNA expression of CCL5 and CCL3 in both BAL and lung tissue cells. In addition RSV infection enhanced expression of 12/15-LOX in both BAL and lung cells. In conclusion, we confirm that RSV infection leads to the increased expression of 12/15 LOX and the related chemokines CCL5 and CCL3 in BAL fluid and lung tissue cells suggesting that the 12/15 LOX pathway could serve as a candidate target for prevention and treatment of RSV infection.


Asunto(s)
Araquidonato 12-Lipooxigenasa/metabolismo , Araquidonato 15-Lipooxigenasa/metabolismo , Quimiocina CCL3/metabolismo , Quimiocina CCL5/metabolismo , Infecciones por Virus Sincitial Respiratorio/inmunología , Animales , Líquido del Lavado Bronquioalveolar/inmunología , Líquido del Lavado Bronquioalveolar/virología , Línea Celular , Quimiocinas/metabolismo , Modelos Animales de Enfermedad , Femenino , Humanos , Inflamación/inmunología , Pulmón/inmunología , Pulmón/virología , Ratones , Ratones Endogámicos BALB C , ARN Mensajero/metabolismo , Virus Sincitiales Respiratorios/inmunología , Virus Sincitiales Respiratorios/patogenicidad
17.
Int J Biol Macromol ; 80: 506-11, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26188301

RESUMEN

In this research, effects of beeswax (BW) on functional properties of whey protein concentrates (WPC):pullulan (PUL) films were investigated. For this purpose, 0, 10, 20 and 30w/w(glycerol)% BW rates and 30:70, 50:50 and 70:30w/w% WPC:PUL ratios were applied. Films containing 70% WPC:30% PUL (WPC70) and 30% BW (BW30) justified the highest contact angle (92.4°) among all films; SEM micrographs indicated that BW could come toward the surface of films during drying stage and resulted in a higher hydrophobic behavior of bilayer films compared with blend films. WPC70 supplied the lowest T(g) values (36-48 °C) among different proportions of WPC-PUL; the highest melting points were just assured in the absence of BW regardless of combination ratio for WPI:PUL. BW30 films deserved lower roughness rates than BW20 (and even BW10) films, indicating more advantageous microstructure and higher hydrogen connections in BW30 films and justifying similar melting points attained for BW30 films to BW20 or 10 ones. Overall, application of WPC70 and BW30 was recommended to obtain optimum combination of final properties for WPC-PUL-BW bilayer films as SEM exhibited flexible and elastic structures of such films.


Asunto(s)
Glucanos/química , Ceras/química , Proteína de Suero de Leche/química , Interacciones Hidrofóbicas e Hidrofílicas , Ensayo de Materiales , Propiedades de Superficie
18.
Carbohydr Polym ; 126: 1-8, 2015 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-25933515

RESUMEN

This paper focuses on the development of an effective methodology to determine the optimum levels of independent variables leading to maximize stability of O/W emulsions containing Arabic gum, as a natural emulsifier and stabilizer. Response surface methodology (RSM) was employed to determine the effect of Arabic gum content (2%, 5%, and 8% (w/w)), homogenization time (5, 12.5, and 20 min) and storage temperature (4, 22, and 40 °C). Image processing was used to determine emulsion stability based on responses including creaming index, centrifugal stability, viscosity, color parameters, and D32 and D43 indices. For each response, a second-order polynomial model with high coefficient of determination (R(2)) values ranging from 0.95 to 0.989 was developed using multiple linear regression analysis. The optimization results showed that the overall optimum region with the highest stability was found to be at the combined levels of 5.81% (w/w) Arabic gum content, 5 min homogenization time, and 22 °C for storage temperature.


Asunto(s)
Acacia/química , Emulsionantes/química , Emulsiones/química , Goma Arábiga/química , Tamaño de la Partícula , Temperatura , Viscosidad
19.
Carbohydr Polym ; 118: 24-9, 2015 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-25542102

RESUMEN

Different ratios of whey protein concentrate (WPC):pullulan (PUL) (70:30, 50:50, 30:70%w/w) and various rates of beeswax (BW) (0, 10, 20, and 30%w/wglycerol) were applied to prepare biodegradable WPC-PUL films containing glycerol as a plasticizer, for the first time. Thickness, moisture content, water solubility, water vapour permeability, colour, and mechanical properties of prepared films were measured. Higher ratios of WPC:PUL led to more desirable physical and mechanical properties; in other words, lower rates of thickness, moisture content, water solubility and water vapour permeability, and higher elongations were achieved. Application of BW (especially in higher contents) could successfully improve colour indices, diminish water solubility (nearly 12%) and water vapour permeability (approximately 3×10(-11)gm(-1)s(-1)Pa(-1)), and increase tensile strength (by about 7MPa) of WPC-PUL blend films. Our edible films enjoyed great whiteness and ignorable yellowness indices, making it a suitable alternative for application in food products. Overall, WPC70-PUL30 containing 30% BW resulted in the best performance of physical and mechanical aspects as an optimum film.


Asunto(s)
Glucanos/química , Membranas Artificiales , Proteínas de la Leche/química , Ceras/química , Biodegradación Ambiental , Proteína de Suero de Leche
20.
Carbohydr Polym ; 109: 148-54, 2014 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-24815411

RESUMEN

Chitosan-nanocellulose biocomposites were prepared from chitosan having molecular weight of 600-800 kDa, nanocellulose with 20-50 nm diameters and various levels of 30, 60 and 90% (v/wCHT) for glycerol. Agitation and sonication were used to facilitate even dispersion of particles in the polymer matrix. The nanocomposites were examined by differential scanning calorimetry, X-ray diffraction and agar disc diffusion tests; finally, the film was applied on the surface of ground meat to evaluate its performance in real terms. Chitosan-nanocellulose nanocomposites showed high Tg range of 115-124°C and were able to keep their solid state until the temperature (Tm) range of 97-99°C. XRD photographs revealed that nanocellulose peak completely disappeared after their addition to chitosan context. Agar disc diffusion method proved that the nancomposite had inhibitory effects against both gram-positive (S. aureus) and gram-negative (E. coli and S. enteritidis) bacteria through its contact area. Application of chitosan-nanocellulose nanocomposite on the ground meat decreased lactic acid bacteria population compared with nylon packaged samples up to 1.3 and 3.1 logarithmic cycles at 3 and 25°C after 6 days of storage, respectively.


Asunto(s)
Celulosa/química , Quitosano/química , Microbiología de Alimentos , Embalaje de Alimentos , Carne/microbiología , Animales , Antibacterianos/química , Antibacterianos/farmacología , Celulosa/farmacología , Quitosano/farmacología , Pruebas Antimicrobianas de Difusión por Disco , Almacenamiento de Alimentos , Temperatura de Transición , Difracción de Rayos X
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