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The desiccant air conditioning system has multiple advantages (e.g., no use of ozone-depleting refrigerants, highly efficient moisture control, easy regenerative integration) over traditional vapor-compression refrigeration systems, thus increasingly attracting more research interest. Recently, several studies have been conducted that primarily aimed to enhance the overall performance of desiccant air conditioners by innovating new desiccant materials, innovating new system configurations and improving system designs and controls, and integrating different hybrid energy sub-systems technologies. Therefore, this paper provides a comprehensive review of the studies mentioned earlier. The present comprehensive review dealt with several axes: first, an overview of the importance of using desiccant air conditioners and their operations, and performance indicators. Second, a summary statement for desiccant materials that includes: the new innovative desiccant materials and the most important composite desiccant materials. Third, detailed information on the newest innovative designs and configurations of desiccant air conditioning systems and their control systems. Fourth, a detailed statement on the most important hybrid energy sub-systems technologies integrated with desiccant air conditioners. Based on the latest developments in desiccant air conditioning systems, this study presents discussions of urgent issues and recommendations for future work that can help focus necessary efforts to find solutions to critical and pending problems, which lead to further improvements in the overall performance of desiccant air conditioners.
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Aire Acondicionado , Higroscópicos , Adsorción , Gases , Productos DomésticosRESUMEN
BACKGROUND: Human MxA gene is related to the class of interferon (IFN)-stimulated genes (ISGs) that plays a role in antiviral resistance. OBJECTIVE: Implementation of standard curves obtained from designing a procedure for data processing in relative qPCR between MxA expression and interferon's antiviral activity (IU/ml). These standard curves can be used to detect the antiviral activity of any new compound rapidly and safely. METHODS: To detect the optimum incubation time for maximum MxA gene expression in human peripheral blood mononuclear cells (PBMC), the isolated human PBMCs (1x106 cells) were incubated with a concentration of 1000 IU/ml of each IFN at different time intervals; 2 h, 4 h, 6 h, and 24 h post-treatment. A standard curve was performed for each IFN (α, ß, and γ) at different concentrations (250, 500, 750, 1000, 1500, and 2000 IU/ml). RESULTS: As observed at 4 h incubation time of 1000 IU/ml concentration, IFN-γ provided a higher expression of MxA compared to IFN-α and IFN-ß. Correlation analyses between IFN-α and IFN-ß, IFN-ß and IFN-γ were non-significant. However, there was a significant correlation between IFN-α and IFN-γ (p<0.01). Receiver operator characteristic (ROC) analysis revealed that cut-off values of IFN- γ, IFN-ß, and IFN-α were 58.14 > 7.31 and > 3.33, respectively. CONCLUSIONS: The relative expression of MxA is a biomarker for IFN-α, ß, and γ, especially IFN-α. It has compiled and validated a standard curve-based protocol for PCR data processing. It shows that the standard curve is an easy alternative tool to assess antiviral activity. We revised all patents relating to the antiviral assays of the used interferons.
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Antivirales , Interferones/farmacología , Leucocitos Mononucleares , Proteínas de Resistencia a Mixovirus , Antivirales/farmacología , Expresión Génica , Humanos , Leucocitos Mononucleares/inmunología , Proteínas de Resistencia a Mixovirus/genética , Patentes como AsuntoRESUMEN
Background: Hepatocellular carcinoma (HCC) is a high incidence disease in Egypt with a poor prognosis and survival. Biomarkers are important for diagnosis of HCC at an early stage. Osteopontin (OPN), a glycoprotein secreted by macrophages, osteoblasts, and T cells, is also highly expressed in a variety of tumors, such as examples in the breast, colon, and stomach. The present study aimed to correlate the serum level of OPN in HCV-positive hepatocellular carcinoma patients, with OPN expression in tumor and non-tumor liver tissues in order to identify its efficacy as a biomarker for diagnosis. Material and Methods: Out of total of 146 patients, 80 were selected for inclusion in the study. Blood samples as well as specimens of tumor and non-tumor liver tissue were collected. In addition, blood samples from 20 healthy volunteers were obtained as controls. Serum OPN and alpha-fetoprotein (AFP) were evaluated by ELISA for HCC and control groups. OPN and AFP gene expression were examined by real-time PCR, after homogenization and DNA extraction from serum samples and liver tissues. Results: It was found that serum OPN levels were significantly higher in the HCC group compared to normal group (P=0.009), with a strong positive correlation with AFP expression. However, there was no significant difference between OPN expression in tumor and non-tumor liver tissue. Conclusion: Serum OPN is highly suggested to be a professional candidate for HCC early diagnosis, with a diagnostic ability and accuracy equal or higher than for AFP.
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Biomarcadores de Tumor/sangre , Carcinoma Hepatocelular/sangre , Hepatitis C Crónica/complicaciones , Neoplasias Hepáticas/sangre , Hígado/metabolismo , Osteopontina/sangre , Adulto , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/virología , Estudios de Casos y Controles , Femenino , Estudios de Seguimiento , Hepacivirus/aislamiento & purificación , Hepatitis C Crónica/virología , Humanos , Hígado/patología , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/virología , Masculino , Persona de Mediana Edad , Pronóstico , Curva ROC , alfa-Fetoproteínas/análisisRESUMEN
Background: Increasing evidence indicates that in hepatocellular carcinomas (HCCs) abnormal gene expression, for example of glypican-3 (GPC-3) and insulin-like growth factor-II (IGF-II), are associated with the occurrence and progression of HCC. The objective of this study was to evaluate the differential expression of GPC-3 and IGF-II mRNAs in HCC tissues with a background of chronic hepatitis C virus (HCV) genotype 4 cirrhosis, in relation to Ki-67 and alpha-feto protein (AFP) tissue markers. Methods: One hundred and five patients with HCCs who had undergone hepatectomy, were included, after obtaining informed consent. Total RNA was extracted from malignant and corresponding peri-malignant liver tissues, and GPC-3 and IGF-II mRNAs in addition to beta-actin mRNA as an internal control, were evaluated in all samples by reverse transcriptase-polymerase chain reactions (RT-PCR). Routine histopathological diagnosis as well as immunohistochemical (IHC) staining using monoclonal antibodies for Ki-67 and AFP were also performed. Result: Expression of GPC-3 mRNA was positive in all HCC malignant tissue, with overexpression in 86/105 (81.9%); in respect to the grade of the tumor (1-3 grades), while in peri-malignant tissue it was over expressed only in 20/105 (19%). The IGF-II mRNA was over expressed in only 10/105 (9.5%) malignant and peri-malignant samples. AFP was expressed in 33.3% of malignant samples but absent in peri-malignant tissues. Ki-67 expression was significantly increased in malignant compared to peri-malignant tissue. Conclusion: GPC-3 and IGF II mRNAs may be good molecular markers for HCC, especially with a background of cirrhosis due to chronic HCV infection. Significant correlations were noted with the pattern of AFP and Ki-67 expression.
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STATEMENT OF PROBLEM: A common reason for replacing a maxillofacial prosthesis is the deterioration of its properties. PURPOSE: The purpose of this study was to compare the effect of weathering in a hot and humid climate on the tear strength, tensile strength, modulus of elasticity, elongation percentage, and color of 3 maxillofacial materials. MATERIAL AND METHODS: Three silicone materials were tested. Specimens were exposed to outdoor weathering for 6 months in a hot and humid environment. Tear and tensile strengths were measured with a universal testing machine before and after outdoor weathering. Color change was evaluated by recording L*, a*, and b* values at base line and after outdoor weathering with a spectrophotometer. The ΔE, ΔL*, Δa*, and Δb* of the specimens were calculated. Data were analyzed with 2-way ANOVA and the post hoc Scheffé test (α=.05). RESULTS: For all tested elastomers, outdoor weathering decreased the tear strength and modulus of elasticity values significantly (P<.001). Also, weathering reduced percentage elongation values significantly (P<.05). Tensile strength values were significantly reduced for TechSil S25 and MED-4210 specimens only (P<.05). The effect of weathering on the color of pigmented specimens was greater than the acceptable value (ΔE>3.0). The color change (ΔE) of pigmented specimens ranged from 4.31 to 6.68. A-2186 silicone elastomer experienced the greatest color changes (P<.05). Within nonpigmented specimens, none of the tested silicone elastomers showed significant color changes (P>.05). CONCLUSIONS: Outdoor weathering in a hot and humid climate adversely affected the properties of silicone elastomers. The heat-polymerized TechSil S25 elastomer showed better mechanical durability and color stability compared with the room-temperature polymerized A-2186 and MED-4210 materials. TechSil S25 showed the greater values of tear and tensile strengths and elongation of specimens exposed to outdoor weathering conditions. It also showed the least amount of color change among the pigmented specimens exposed to outdoor weathering.
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Materiales Biocompatibles/química , Clima , Prótesis Maxilofacial , Diseño de Prótesis , Elastómeros de Silicona/química , Color , Dimetilpolisiloxanos/química , Módulo de Elasticidad , Elasticidad , Calor , Humanos , Humedad , Ensayo de Materiales , Fenómenos Mecánicos , Docilidad , Polimerizacion , Coloración de Prótesis , Espectrofotometría/instrumentación , Propiedades de Superficie , Resistencia a la TracciónRESUMEN
Orthotropic Liver transplantation (OLT) is a conventional management for end-stage acute or chronic liver insufficiency, but the shortage of donor organs continues to be the restrictive factor throughout the world. Hepatocyte transplantation (HCTx) might be the promising treatment for several liver diseases and can be used as a "bridge" to OLT. Hepatocytes transplantation can protect and even save human lives, its' applicability remains limited by the large deficiency of liver organs and hepatocytes (HC), and cellular loss after engraftment. Host elimination of grafted cells is called Early Graft Dysfunction. This study was developed for an efficient protocol of HCT. Several conditions have been met in order to achieve a high yield of harvested viable HC, overcome the detached-cell apoptosis, attenuation of innate immune reaction against transplanted cells and a receptive cell environment. HC were isolated from Lewis rats (n = 8) weighing 250 gm, by the 2 step collagen a seper fusion technique, and bone marrow cells (BMCs) were obtained from the rats tibia and femur by centrifugation in a buffer solution. The mean viability of harvested HC and BMCs were 90% and 95% respectively. To minimize the rejection of HC, Lewis rat recipients (n = 14) weighing 250 gm, were irradiated with 6 Gy and received 0.1 mg of anti-aisle GMI antiserum intravenously as immunosuppressive drug. The isolated HC were intra-splenically transplanted and 10(7) bone marrow cells were injected in a penile vein into the recipients on the third day. Simultaneously, 70% hepatectomy and ligation of common bile duct were done. Thirty days later; the grafted spleen had areas with external appearance of a normal liver in ten out of 14 surviving rats (71%). Hematoxlin and eosin (H & E) staining of sections from these fragments showed sinusoids and portal areas, an evidence of successful hepatocyte engraftment and bile canaliculea formation. Large number of HC clusters of 15 to 20 cells and 2 to 4 distended small bile canaliculea were seen per 50 HC. The intrasplenic route for transplanting freshly isolated HC in an immune-compromised animal model was found to give good results regarding cell engraftment and tissue formation.
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Hepatectomía/efectos adversos , Hepatocitos/trasplante , Fallo Hepático Agudo/terapia , Animales , Células de la Médula Ósea , Huésped Inmunocomprometido , Masculino , Ratas , Ratas Endogámicas LewRESUMEN
BACKGROUND AND AIMS: The role of insulin resistance (IR) in chronic hepatitis C genotype 4 (CHC-4) patients is still under assessment. The aims of this study are to assess the prevalence and predictors of IR and its influence along with clinical, metabolic, virological, and histological factors on the severity of liver fibrosis in 100 Egyptian patients with CHC-4. PATIENTS AND METHODS: In 100 untreated patients with CHC-4, IR was assessed using the Homeostasis Model Assessment and defined greater than 3. By logistic regression (LR), independent factors associated with IR and significant fibrosis (SF=fibrosis, Metavir score≥F2) were assessed in nondiabetic and noncirrhotic patients. RESULTS: One hundred patients were included; 54% were men and 46% were women. The mean age of the patients was 40.46±9.41 years. Of the total patients, 55% were overweight and 28% were obese. Metabolic syndrome was observed in 26% of patients; five of them were known to be diabetic. All patients were genotype 4. Most of our patients had mild viremia (<2 00 000 IU/ml), whereas only 16% had higher viral load (>2 00 000 IU/ml). There was no correlation between IR and hepatitis C virus viremia (r=-0.069; P=0.492). Necroinflammation was moderate-severe (A2-A3) in 25% of patients. SF (F2-F4) was found in 46% of patients and 11% had cirrhosis (F4). Most of our patients, 54%, had moderate steatosis and 21% had severe steatosis. IR was present in 46% of patients; 39 (42.9%) were nondiabetic, which is correlated significantly with BMI (r=0.395; P<0.01). IR was found to increase significantly with the fibrosis stage (P=0.001), insignificant fibrosis, 18.5%, SF (F2-F4), 71.4%, and cirrhosis (F4), 100%. By LR, IR was independently and significantly associated with age more than 40 years, obesity (BMI>30 kg/m), SF, and severe steatosis (>30%). IR was also significantly associated with metabolic syndrome. SF was present in 46 patients (46%). It was associated with IR, moderate-severe necroinflammation, and severe steatosis. By LR, in noncirrhotic patients, SF was associated with age more than 40 years, obesity (BMI>30 kg/m), moderate/severe liver inflammation, and severe steatosis. CONCLUSION: In CHC-4 patients, IR is highly prevalent and independently associated with age, obesity, SF, and severe steatosis. Management of IR might significantly improve the prognosis of CHC-4 patients.
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Hepatitis C Crónica/complicaciones , Resistencia a la Insulina/fisiología , Cirrosis Hepática/virología , Adulto , Factores de Edad , Índice de Masa Corporal , Hígado Graso/fisiopatología , Hígado Graso/virología , Femenino , Genotipo , Hepacivirus/genética , Hepacivirus/aislamiento & purificación , Hepatitis C Crónica/patología , Hepatitis C Crónica/fisiopatología , Hepatitis C Crónica/virología , Humanos , Cirrosis Hepática/patología , Cirrosis Hepática/fisiopatología , Masculino , Persona de Mediana Edad , Obesidad/complicaciones , Obesidad/fisiopatología , Estudios Prospectivos , Factores de Riesgo , Índice de Severidad de la EnfermedadRESUMEN
The development of multivalent vaccines consisting of several antigens is a novel approach to creating broad-range protection against different parasite strains and parasite life cycle stages. We have previously confirmed that the schistosome Sm21.7 and SmFimbrin (SmFim) proteins could induce protection in mice. Therefore, this study aimed to construct the multivalent DNA vaccine Sm21.7-SmFim/pBudCE4.1 and evaluate its immune efficacy. The open reading frames of two Schistosoma mansoni genes, Sm21.7 and SmFim, were inserted into the eukaryotic expression plasmid pBudCE4.1 designed for the independent expression of two genes in mammalian cells. To evaluate the in vitro expression of the multivalent Sm21.7-SmFim/pBudCE4.1 DNA vaccine and its immunological effect in mice, the recombinant plasmid Sm21.7-SmFim/pBudCE4.1 was used to transfect 293T cells, and the expression of mRNA and proteins was examined using reverse transcription-polymerase chain reaction and Western blot analysis. Then the ability of Sm21.7-SmFim/pBudCE4.1 to protect against S. mansoni challenge infections was analyzed according to worm burden and egg reduction rates after vaccination of mice. Vaccinated mice showed a significant level of protection (56%), and a decrease in the number and size, and change in the cellular profile, of granulomas. Egg reduction in liver and intestine was 41.53% and 55.63%, respectively, as determined relative to mice that received the empty vector only. In addition to reductions in worm viability, worm fecundity and egg hatching ability were observed following challenge infection in the immunized group. Results showed that Sm21.7-SmFim/pBudCE4.1 could express Sm21.7 and SmFim mRNA and proteins. Enzyme-linked immunosorbent assay and Western blot analysis indicated that immunized mice generated specific immunoglobulin G against Sm21.7-SmFim/pBudCE4.1. These results suggest that vaccination with multivalent S. mansoni DNA vaccine (SmFim-Sm21.7/pBudCE4.1) not only induces a significant reduction in worm and egg burdens, but also significantly reduces the size of egg granulomas. In summary, the multivalent vaccine stimulated specific immunity with a significant level of protection and has anti-pathological effect.
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Antígenos Helmínticos/inmunología , Antígenos Helmínticos/uso terapéutico , Inmunización Pasiva/métodos , Schistosoma mansoni/inmunología , Esquistosomiasis mansoni/inmunología , Esquistosomiasis mansoni/prevención & control , Vacunas de ADN/inmunología , Vacunas de ADN/uso terapéutico , Animales , Antígenos Helmínticos/genética , Diseño de Fármacos , Femenino , Ratones , Resultado del Tratamiento , Vacunas de ADN/química , Vacunas de ADN/genéticaRESUMEN
beta-Thalassemia (thal), the most common genetic disorder in Egypt, is a major health problem with an estimated carrier rate of 9-10%. This study, aimed at describing the beta-globin gene mutations in the Suez Canal area, an important Egyptian region, to provide a foundation for a disease control program. We studied 44 beta-thalassemic patients (and their relatives) from 35 families living in this region. The commonest mutations were genetically diagnosed using naturally or amplified created restriction sites. Less frequent mutations were characterized by denaturing gradient gel electrophoresis (DGGE) and direct sequencing. Twelve different mutations were identified in 51 unrelated chromosomes. The three most frequent mutations were IVS-I-110 (G-->A), IVS-I-1 (G-->A) and IVS-I-6 (T-->C). The spectrum of rarer mutations was heterogeneous and differed from that reported in other areas of Egypt. We also identified the first homozygous case of a rare mutation, codon 24 (-G; +CAC), displaying a thalassemia major phenotype. Parental consanguinity was high (60.6%) with 35.7% of the compound heterozygous patients having consanguineous parents. These data provide insights for the distribution of beta-thal alleles in this region, and could be used as a basis for genetic counseling and prenatal diagnosis.