64 research outputs found

    Behavioral Problems among Visually Impaired Children Studying at Special School for Blindness

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    Context: Visual impairment and blindness are significant ophthalmic disorders around the world. Behavioral problems in visually impaired children are considered one of the most serious health problems.Aim: The study aimed to assess behavioral problems among visually impaired children studying at a special school for blindness and assess the association between behavioral problems scores and selected demographic variables of studied children. Methods: The research design adopted for this study was a descriptive correlational design. A purposive sample was composed of one hundred and one (101) parents of children with visual impairment. The children were studying at El Nour School for blindness in Minia city. The data were collected using the parents' interview questionnaire and Child Behavior Checklist/4-18 (CBCL/4-18).Results: Withdrawn syndrome represented the highest clinical level among the studied children, followed by aggressive clinical behavior. Also, less than a fifth of them had to internalize clinical problems, and 17.8% of them had to externalize clinical problems. A highly statistically significant correlation was revealed between the score of total behavior syndromes and the age of studied children. Conclusion: Visually impaired children had problems in the total social competence score and all its subscales. About one-third of them had borderline and clinical problems regarding the total score of behavioral syndromes. Also, internalized and externalized problems had reported. The study recommended that further intervention studies are necessary, including parents' classes about behavioral problems of visually impaired children and methods to limit its effect on children's lives

    Securing IP Mobility Management for Vehicular Ad Hoc Networks

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    The proliferation of Intelligent Transportation Systems (ITSs) applications, such as Internet access and Infotainment, highlights the requirements for improving the underlying mobility management protocols for Vehicular Ad Hoc Networks (VANETs). Mobility management protocols in VANETs are envisioned to support mobile nodes (MNs), i.e., vehicles, with seamless communications, in which service continuity is guaranteed while vehicles are roaming through different RoadSide Units (RSUs) with heterogeneous wireless technologies. Due to its standardization and widely deployment, IP mobility (also called Mobile IP (MIP)) is the most popular mobility management protocol used for mobile networks including VANETs. In addition, because of the diversity of possible applications, the Internet Engineering Task Force (IETF) issues many MIP's standardizations, such as MIPv6 and NEMO for global mobility, and Proxy MIP (PMIPv6) for localized mobility. However, many challenges have been posed for integrating IP mobility with VANETs, including the vehicle's high speeds, multi-hop communications, scalability, and ef ficiency. From a security perspective, we observe three main challenges: 1) each vehicle's anonymity and location privacy, 2) authenticating vehicles in multi-hop communications, and 3) physical-layer location privacy. In transmitting mobile IPv6 binding update signaling messages, the mobile node's Home Address (HoA) and Care-of Address (CoA) are transmitted as plain-text, hence they can be revealed by other network entities and attackers. The mobile node's HoA and CoA represent its identity and its current location, respectively, therefore revealing an MN's HoA means breaking its anonymity while revealing an MN's CoA means breaking its location privacy. On one hand, some existing anonymity and location privacy schemes require intensive computations, which means they cannot be used in such time-restricted seamless communications. On the other hand, some schemes only achieve seamless communication through low anonymity and location privacy levels. Therefore, the trade-off between the network performance, on one side, and the MN's anonymity and location privacy, on the other side, makes preservation of privacy a challenging issue. In addition, for PMIPv6 to provide IP mobility in an infrastructure-connected multi-hop VANET, an MN uses a relay node (RN) for communicating with its Mobile Access Gateway (MAG). Therefore, a mutual authentication between the MN and RN is required to thwart authentication attacks early in such scenarios. Furthermore, for a NEMO-based VANET infrastructure, which is used in public hotspots installed inside moving vehicles, protecting physical-layer location privacy is a prerequisite for achieving privacy in upper-layers such as the IP-layer. Due to the open nature of the wireless environment, a physical-layer attacker can easily localize users by employing signals transmitted from these users. In this dissertation, we address those security challenges by proposing three security schemes to be employed for different mobility management scenarios in VANETs, namely, the MIPv6, PMIPv6, and Network Mobility (NEMO) protocols. First, for MIPv6 protocol and based on the onion routing and anonymizer, we propose an anonymous and location privacy-preserving scheme (ALPP) that involves two complementary sub-schemes: anonymous home binding update (AHBU) and anonymous return routability (ARR). In addition, anonymous mutual authentication and key establishment schemes have been proposed, to authenticate a mobile node to its foreign gateway and create a shared key between them. Unlike existing schemes, ALPP alleviates the tradeoff between the networking performance and the achieved privacy level. Combining onion routing and the anonymizer in the ALPP scheme increases the achieved location privacy level, in which no entity in the network except the mobile node itself can identify this node's location. Using the entropy model, we show that ALPP achieves a higher degree of anonymity than that achieved by the mix-based scheme. Compared to existing schemes, the AHBU and ARR sub-schemes achieve smaller computation overheads and thwart both internal and external adversaries. Simulation results demonstrate that our sub-schemes have low control-packets routing delays, and are suitable for seamless communications. Second, for the multi-hop authentication problem in PMIPv6-based VANET, we propose EM3A, a novel mutual authentication scheme that guarantees the authenticity of both MN and RN. EM3A thwarts authentication attacks, including Denial of service (DoS), collusion, impersonation, replay, and man-in-the-middle attacks. EM3A works in conjunction with a proposed scheme for key establishment based on symmetric polynomials, to generate a shared secret key between an MN and an RN. This scheme achieves lower revocation overhead than that achieved by existing symmetric polynomial-based schemes. For a PMIP domain with n points of attachment and a symmetric polynomial of degree t, our scheme achieves t x 2^n-secrecy, whereas the existing symmetric polynomial-based authentication schemes achieve only t-secrecy. Computation and communication overhead analysis as well as simulation results show that EM3A achieves low authentication delay and is suitable for seamless multi-hop IP communications. Furthermore, we present a case study of a multi-hop authentication PMIP (MA-PMIP) implemented in vehicular networks. EM3A represents the multi-hop authentication in MA-PMIP to mutually authenticate the roaming vehicle and its relay vehicle. Compared to other authentication schemes, we show that our MA-PMIP protocol with EM3A achieves 99.6% and 96.8% reductions in authentication delay and communication overhead, respectively. Finally, we consider the physical-layer location privacy attacks in the NEMO-based VANETs scenario, such as would be presented by a public hotspot installed inside a moving vehicle. We modify the obfuscation, i.e., concealment, and power variability ideas and propose a new physical-layer location privacy scheme, the fake point-cluster based scheme, to prevent attackers from localizing users inside NEMO-based VANET hotspots. Involving the fake point and cluster based sub-schemes, the proposed scheme can: 1) confuse the attackers by increasing the estimation errors of their Received Signal Strength (RSSs) measurements, and 2) prevent attackers' monitoring devices from detecting the user's transmitted signals. We show that our scheme not only achieves higher location privacy, but also increases the overall network performance. Employing correctness, accuracy, and certainty as three different metrics, we analytically measure the location privacy achieved by our proposed scheme. In addition, using extensive simulations, we demonstrate that the fake point-cluster based scheme can be practically implemented in high-speed VANETs' scenarios

    2,4-CYCLOADDITION REACTIONS: PREPARATION AND CYTOTOXICITY OF NOVEL QUINOLINE AND PYRROLO [3,4-f] QUINOLINE DERIVATIVES

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    Objective: the present work aimed to synthesize novel quinoline and pyrroloquinoline derivatives and study their cytotoxic activity.Methods: Dielsñ€“Alder reaction (4+2) was used for the synthesis of new quinolone and pyrrolo quinoline derivatives via the reactions of compound 1 with N-maleimide (4a-d) derivatives, ethyl acrylate (6) methylmethacrylate (8) and acetylene dicarboxylic acid (10). The synthesized compounds were characterized by NMR and Mass spectral data. Some of the synthesized compounds were screened for their antitumor activity against three different cell lines (MCF-7, HepG2 and HCT).Results: The tested compounds exhibited antiproliferative activity against the three different cell lines, especially against MCF-7.Conclusion: New quinoline and pyrroloquinoline derivatives were synthesized starting with 6-methyl-4-phenyl-2-thioxo-5-(4-methylphenylthio)-1,2-dihydropyridine-3-carbonitrile. Two new compounds 3 and 5a were tested for their in vitro antiproliferative activity against MCF-7, HepG2 and HCT cancer cell lines. The result showed that compound 3 exhibited more potent antiproliferative activity than compound 5a in case of MCF-7 and HCT cell lines.Â

    Impact of Culture Media Composition, Nutrients Stress and Gamma Radiation on Biomass and Lipid of the Green Microalga, Dictyochloropsis splendida as a Potential Feedstock for Biodiesel Production

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    يŰčŰȘÙ…ŰŻ Ű„Ù†ŰȘۧۏ Ű§Ù„ŰŻÙŠŰČل Ű§Ù„Ű­ÙŠÙˆÙŠ من Ű§Ù„Ű·Ű­Ű§Ù„Űš Ű§Ù„ŰŻÙ‚ÙŠÙ‚Ű© Űčلى Ű„Ù†ŰȘۧۏ Ű§Ù„ÙƒŰȘÙ„Ű© Ű§Ù„Ű­ÙŠÙˆÙŠŰ© ÙˆÙ…Ű­ŰȘوى Ű§Ù„ŰŻÙ‡ÙˆÙ†. يŰȘم Ű§Ù„ŰȘŰ­ÙƒÙ… في ŰČÙŠŰ§ŰŻÙ‡ Ű§Ù†ŰȘۧۏ Ű§Ù„ÙƒŰȘÙ„Ű© Ű§Ù„Ű­ÙŠÙˆÙŠŰ© و ŰȘŰ±Ű§ÙƒÙ… Ű§Ù„ŰŻÙ‡ÙˆÙ† ŰšÙˆŰ§ŰłŰ·Ű© ŰčŰŻŰ© ŰčÙˆŰ§Ù…Ù„.فى Ù‡Ű°Ű§ Ű§Ù„Űčمل ŰȘم ۯ۱ۧ۳۩ ŰȘŰŁŰ«ÙŠŰ±Ű§ŰȘ Ű«Ù„Ű§Ű« Ű§ÙˆŰłŰ§Ű· ŰșŰ°Ű§ŰŠÙŠÙ‡ ۟ۧ۔۩ ŰšŰČ۱ۧŰčŰ© Ű§Ù„Ű·Ű­Ű§Ù„Űš ( BG11, BBM, Urea media) ÙˆŰ§ÙŠŰ¶Ű§ ŰšŰč۶ Ű§Ù„Ù…ŰșŰ°ÙŠŰ§ŰȘ)Ű§Ù„Ù†ÙŠŰȘŰ±ÙˆŰŹÙŠÙ† ÙˆŰ§Ù„ÙÙˆŰłÙÙˆŰ±Ùˆ Ű§Ù„Ù…ŰșÙ†ÙŠŰłÙŠÙˆÙ… ÙˆŰ§Ù„ÙƒŰ±ŰšÙˆÙ†) ÙˆŰ§ŰŽŰčŰ© ŰŹŰ§Ù…Ű§ Űčلى نمو ÙˆŰ§Ù†ŰȘۧۏ Ű§Ù„ŰŻÙ‡ÙˆÙ† Ù„Ű·Ű­Ű§Ù„Űš Dictyochloropsis splendida. ŰȘم Ű§Ù„Ű­Ű”ÙˆÙ„ Űčلي ŰŁŰčلي Ű§Ù†ŰȘۧۏ للكŰȘله Ű§Ù„Ű­ÙŠÙˆÙŠÙ‡ ÙˆŰ§Ù„ŰŻÙ‡ÙˆÙ† Ù„Ű·Ű­Ù„Űš Dictyochloropsis splendida  ŰčÙ†ŰŻÙ…Ű§ ŰȘم ŰČ۱ۧŰčŰ© Ű§Ù„Ű·Ű­Ù„Űš Űčلى Ű§Ù„ÙˆŰłŰ· Ű§Ù„ŰșŰ°Ű§ŰŠÙŠ BG11 . ŰčÙ„Ű§ÙˆŰ© Űčلى Ű°Ù„Ùƒ ÙƒŰ§Ù† ۧŰčلى Ű§Ù†ŰȘŰ§ŰŹÙŠŰ© للكŰȘله Ű§Ù„Ű­ÙŠÙˆÙŠÙ‡ ŰčÙ†ŰŻ 3000 Ù…Ù„ÙŠŰŹŰ±Ű§Ù… / لŰȘ۱ نيŰȘŰ±ÙˆŰŹÙŠÙ† Ű§Ùˆ 160 Ù…Ù„ÙŠŰŹŰ±Ű§Ù… / لŰȘ۱ ÙÙˆŰłÙÙˆŰ± Ű§Ùˆ 113 Ù…Ù„ÙŠŰŹŰ±Ű§Ù…/لŰȘ۱ مŰșÙ†ŰłÙŠÙˆÙ… Ű§Ùˆ 20 Ù…Ù„ÙŠŰŹŰ±Ű§Ù…/ لŰȘ۱ ÙƒŰ±ŰšÙˆÙ†Ű§ŰȘ.  ŰšÙŠÙ†Ù…Ű§ ŰčÙ†ŰŻ ŰșÙŠŰ§Űš Ű§Ù„Ù…ŰșŰ°ÙŠŰ§ŰȘ ÙŰ§Ù† ŰȘŰ±Ű§ÙƒÙ… Ű§Ù„ŰŻÙ‡ÙˆÙ† ŰČۧۯ. من Ù†Ű§Ű­ÙŠŰ© Ű§ŰźŰ±Ù‰ ÙŰ§Ù† Ű§Ù„Ù…Ű­ŰȘوى Ű§Ù„ŰŻÙ‡Ù†Ù‰ Ù„Ù„Ű·Ű­Ù„Űš ÙˆŰ”Ù„ Ű§Ù„Ù‰ 18.26% ŰčÙ†ŰŻÙ…Ű§ ŰȘŰč۱۶ŰȘ ŰźÙ„Ű§ÙŠŰ§ Ű§Ù„Ű·Ű­Ù„Űš Ù„ŰŹŰ±ŰčŰ© 25 ŰŹŰ±Ű§Ù‰ من ۧێŰčŰ© ŰŹŰ§Ù…Ű§. ÙˆÙƒŰ§Ù†ŰȘ  Ű§Ù„ŰŻÙ‡ÙˆÙ† Ű§Ù„Ù…ŰłŰȘŰźÙ„Ű”Ű© من Ű§Ù„Ű·Ű­Ù„Űš ŰȘŰȘكون من Ù†ŰłŰšŰ© ŰčŰ§Ù„ÙŠŰ© من Ű§Ù„Ű§Ű­Ù…Ű§Ű¶ Ű§Ù„ŰŻÙ‡Ù†ÙŠŰ© Ű§Ù„Ù…ŰŽŰšŰčŰ© (SFAs, 63.33% ) ÙˆŰ§Ù„Ű§Ű­Ù…Ű§Ű¶ Ű§Ù„ŰŻÙ‡Ù†ÙŠŰ© Ű§Ù„ŰșÙŠŰ±Ù…ŰŽŰšŰčŰ© (UFAs, 37.02%) ÙˆÙƒŰ§Ù†ŰȘ Ű§Ù„ŰłÙŠŰ§ŰŻŰ© Ù„Ű­Ù…Ű¶ Ű§Ù„ŰšŰ§Ù„Ù…ŰȘيك (C16:0) Ű«Ù… Ű­Ù…Ű¶ Ű§Ù„Ù„ÙŠÙ†ÙˆÙ„ÙŠÙƒ (C18:2) ÙŰ­Ù…Ű¶ ŰšÙ†ŰȘŰ§ŰŻÙŠÙƒŰ§Ù†ÙˆÙŠÙƒ (C15:0) ÙˆŰ­Ù…Ű¶ ŰšŰ§Ù„Ù…ÙŠŰȘوليك (C16:1). و ŰȘÙ…Ű«Ù„ Ű§Ù„Ű§Ű­Ù…Ű§Ű¶ Ű§Ù„ŰŻÙ‡Ù†ÙŠŰ© Ű§Ù„Ù…ŰłŰȘŰźÙ„Ű”Ù‡ من Ű·Ű­Ù„Űš Dictyochloropsis splendida ŰšÙ‡Ű°Ű§ Ű§Ù„ŰȘŰ±ÙƒÙŠŰš Ù…ÙˆŰ§ŰŻ ŰźŰ§Ù… ÙˆŰ§ŰčŰŻŰ© Ù„Ű§Ù†ŰȘۧۏ Ű§Ù„ŰŻÙŠŰČل Ű§Ù„Ű­ÙŠÙˆÙŠ.Biodiesel production from microalgae depends on the biomass and lipid production. Both biomass and lipid accumulation is controlled by several factors. The effect of various culture media (BG11, BBM, and Urea), nutrients stress [nitrogen (N), phosphorous (P), magnesium (Mg) and carbonate (CO3)] and gamma (Îł) radiation on the growth and lipid accumulation of   Dictyochloropsis splendida were investigated. The highest biomass and lipid yield of D. splendida were achieved on BG11 medium. Cultivation of D. splendida in a medium containing 3000 mg L−1 N, or 160 mg L−1 P, or 113 mg L−1 Mg, or 20 mg L-1 CO3, led to enhanced growth rate. While under the low concentrations of nutrients caused a marked increase in the lipid content. Cultures exposure to 25 Gy of Îł-rays, led to an increase in lipid content up to 18.26 ± 0.81 %. Lipid profile showed the maximum presence of saturated fatty acids (SFAs, 63.33%), and unsaturated fatty acids (UFAs, 37.02%). Fatty acids (FAs) recorded the predominance of C16:0, C18:2, C15:0 and C16:1, which strongly proved D. splendida is a promising feedstock for biodiesel production.        

    Serum Soluble CD93 as a Biomarker of Asthma Exacerbation in Children

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    Background: Asthma is considered one of the most prevalent diseases affecting over than 300 million individuals worldwide. Soluble CD93 was normally detected in human plasma and induced by the inflammatory mediators TNF-α and LPS, suggesting that physiologic pathways trigger the cleavage event. Objective: To evaluate the diagnostic value of serum soluble CD93 level in acute asthma exacerbation in children and to find if there is a relation between serum level of soluble CD93 and acute exacerbations of asthma among children. Patients and Methods: Our study included 30 patients who were diagnosed as acute asthmatics with acute exacerbation (diagnosed and classified according to GINA 2018) as group I. Group Π, which included the same 30 patients after receiving treatment and relieve of symptoms by clinical examination as well as routine laboratory investigations that confirmed their healthy state. Plasma sCD93 concentration using ELISA (at the time of exacerbation and repeated on the follow up day) and spirometry were done. Results: Regarding severity (after classification of cases into intermittent, mild and moderate), there was no statistical significance difference in severity either pre- or post-treatment. Regarding sCD93, there was statistical significance reduction in sCD 93 level post-treatment compared to pre-treatment in all cases. There were no statistical significance relation between gender, residence and family history and sCD 93 levels among the studied group. There were no statistical significance relation between WBCs and x-ray and sCD 93 levels among the studied group. Conclusion: sCD93 was not affected by gender or age and did not affect by reliever or controller medications. sCD93 showed a modest decrease in the controlled stage of asthma, which allowed to interpret its role as inflammatory biomarker

    Association of the serum chemerin level with the development of diabetic retinopathy in patients with type 1 diabetes mellitus

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    Background: In patients with type 2 diabetes mellitus, the development of diabetic retinopathy (DR) correlates positively with elevated serum chemerin levels. This study was aimed at investigating the probable association between the serum chemerin level and the development of DR in patients with type 1 diabetes mellitus (T1DM). Methods: In this cross-sectional study, we included Egyptians and classified them into four groups: group 1, including healthy individuals; group 2, including patients with T1DM without DR; group 3, including patients with T1DM with non-proliferative DR (NPDR); and group 4, including patients with T1DM with proliferative DR (PDR). The assessment included best-corrected distance visual acuity assessment, slit-lamp biomicroscopy, funduscopy, fundus fluorescein angiography, and macular ocular coherence tomography. Fasting blood samples were obtained from all participants to measure serum chemerin, glycated hemoglobin (HbA1c), total cholesterol, triglyceride, and creatinine levels. Serum chemerin levels were compared among the groups, and their correlations with age, duration of diabetes, HbA1c, total cholesterol, triglyceride, and creatinine levels were analyzed. Results: We recruited 209 participants, including 46 healthy individuals in group 1, 52 patients (T1DM and no DR) in group 2, 61 patients (T1DM and NPDR) in group 3, and 50 patients (T1DM and PDR) in group 4, with comparable mean ages and sex ratios among groups. The diabetes duration, body mass index, HbA1c, total cholesterol, triglyceride, and serum chemerin levels differed significantly among the groups (all P < 0.001), whereas the creatinine level did not (P > 0.05). The serum chemerin level was significantly higher in group 4 than in groups 3 and 2, in group 3 than in group 2, and in groups 3 and 4 than in group 1 (all P < 0.001). However, it was comparable between groups 1 and 2 (P > 0.05). It correlated with the duration of T1DM and HbA1c, total cholesterol, triglyceride, and creatinine levels but not with age. Conclusions: Patients with T1DM with DR showed higher serum chemerin levels than those with T1DM without DR or healthy individuals. Serum chemerin levels were higher in those with PDR than in those with NPDR. Thus, serum chemerin levels are a potential biomarker of the development and severity of DR in patients with T1DM. Nevertheless, future diagnostic accuracy studies are required to confirm these potential applications

    Levels of certain tumor markers as differential factors between bilharzial and non-biharzial bladder cancer among Egyptian patients

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    <p>Abstract</p> <p>Background/Objective</p> <p>Bladder cancer is the commonest type of malignant tumors as a result of schistosomaisis which is a major healthy problem in many subtropical developing countries. The aim of this study is to comparatively elucidate the underlying biochemical tumor markers in schistosomal bladder cancer versus non-schistosomal bladder cancer when compared to normal healthy ones.</p> <p>Methods</p> <p>This work was performed on tissue specimens from total 25 patients and serum samples from total 30 patients versus ten healthy individuals served as control. The investigated parameters in serum are: xanthine oxidase (XO), fructosamine, lactate dehydrogense (LDH), aspartate aminotransferase (AST), alanine aminotransferase (ALT), total proteins, essential and non- essential amino acids profile, hydroxyproline, total immunoglobulin E (IgE) and tumor necrosis factor alpha (TNF-<it>α</it>). In addition, the current investigation also extended to study some markers in tumor bladder tissues including, pyruvate kinase enzyme (PK), lactate dehydrogenase (LDH), aspartate aminotransferase (AST) and alanine aminotransferase (ALT).</p> <p>Results</p> <p>Results showed that biharzial bladder cancer patients recored more significant elevation in serum XO, fructosamine, LDH, AST, ALT, hydroxyproline, IgE and TNF-<it>α </it>than in bladder cancer patients when compared to control ones. While, in tissues there were significant increase in PK, LDH, AST & ALT activities of schistosomal bladder cancer than in bladder cancer as compared to control healthy patients.</p> <p>Conclusions</p> <p>It could be concluded that, bilharzial and non-bilharzial bladder cancer showed distinct biochemical profile of tumor development and progression which can be taken into consideration in diagnosis of bladder cancer.</p

    Nano-encapsulation of a novel anti-Ran-GTPase peptide for blockade of regulator of chromosome condensation (RCC1) function in MDA-MB-231 breast cancer cells

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    Ran is a small ras-related GTPase and is highly expressed in aggressive breast carcinoma. Overexpression induces malignant transformation and drives metastatic growth. We have designed a novel series of anti-Ran-GTPase peptides, which prevents Ran hydrolysis and activation, and although they display effectiveness in silico, peptide activity is suboptimal in vitro due to reduced bioavailability and poor delivery. To overcome this drawback, we delivered an anti-Ran-GTPase peptide using encapsulation in PLGA-based nanoparticles (NP). Formulation variables within a double emulsion solvent evaporation technique were controlled to optimise physicochemical properties. NP were spherical and negatively charged with a mean diameter of 182–277 nm. Peptide integrity and stability were maintained after encapsulation and release kinetics followed a sustained profile. We were interested in the relationship between cellular uptake and poly(ethylene glycol) (PEG) in the NP matrix, with results showing enhanced in vitro uptake with increasing PEG content. Peptide-loaded, pegylated (10% PEG)-PLGA NP induced significant cytotoxic and apoptotic effects in MDA-MB-231 breast cancer cells, with no evidence of similar effects in cells pulsed with free peptide. Western blot analysis showed that encapsulated peptide interfered with the proposed signal transduction pathway of the Ran gene. Our novel blockade peptide prevented Ran activation by blockage of regulator of chromosome condensation 1 (RCC1) following peptide release directly in the cytoplasm once endocytosis of the peptide-loaded nanoparticle has occurred. RCC1 blockage was effective only when a nanoparticulate delivery approach was adopted

    Evaluation of the Native Killer Yeasts against the Postharvest Phytopathogenic mould of Balady Orange Fruits

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    Yeasts are some of the most important postharvest biocontrol agents (BCAs). Postharvest oranges frequently deteriorate due to green and blue moulds, leading to significant economic losses. The purposes of the present study were to isolate blue and green moulds from infected orange fruits, to assess the ability of killer yeasts isolated from healthy orange fruits and leaves from orange orchards to control blue and green moulds and to evaluate the additive effect of BCAs in combination with 2% sodium bicarbonate (SBC), 2%, sodium benzoate (SB), 2% calcium chloride, 0.2% salicylic acid (SA) or 0.5% chitosan. Among eight fungi isolated from orange fruits showing symptoms of green and blue mulds infection, two were identified as P. digitatum and P. italicum and selected for in vitro assays. Twenty eight yeast isolates were obtained from orange leaves and from the surface of fruits. All yeasts exhibited high killer activity. Twelve yeasts reduced 22.5 –70% of P. digitatum growth while seven isolates reduced 21.1- 68.5% of P. italicum growth. The most potent yeast isolates were identified as Candida pseudotropicalis, Candida salmanticensis, Candida membranifaciens and Pichia guilliermondii. Combination of the BCAs, C. pseudotropicalis, C. salmanticensis and P. guilliermondii with SBC, CaCl2 or chitosan increased their effectiveness against P. digitatum. While combination of C. pseudotropicalis, C. membranifaciens and P. guilliermondii with these natural compounds decreased their effectiveness against P. italicum. Combination of C. membranifaciens with SA increased its effectiveness against P. digitatum. Sodium benzoate has additive effect on C. pseudotropicalis against P. digitatum and C. pseudotropicalis and P. guilliermondii against P. italicum

    Seroprevalence of Mycobacterium avium subsp. paratuberculosis in Dairy Cattle in Khartoum State, Sudan

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    Paratuberculosis, caused by Mycobacterium avium subspecies paratuberculosis (MAP), is a chronic wasting disease mainly of domestic and wild ruminants. It occurs worldwide, causing significant economic losses through decreased productivity, low fertility, increased cull rates and mortality. It is listed by the OIE (World Organization for Animal Health) as a disease of concern to trade in animals. Prevalence of this disease can be studied by detecting anti-MAP antibodies by Enzyme linked immunosorbent Assay (ELISA). The aim of this study was to investigate the current prevalence of MAP infection in cattle in Khartoum State. The overall apparent prevalence of MAP infection was found to be 6.3% and 18.9% at animal and herd levels, respectively. All seropositive animals were cross-bred females of good body condition; most of them (>90%) were >3 years old and >50% were from medium-sized herds in Omdurman. No significant association (p > 0.05) was found between seropositivity and animal herd size. The prevalence of MAP infection in Khartoum State is still low to medium compared to other parts of the world, but it is comparable to those reported from other African countries. Further studies with the view of designing nationwide surveys in domestic ruminants and camels in other states of the country are needed for establishing control programmes
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