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This paper investigates the propagation of sub-Terahertz (THz) electromagnetic waves within an indoor environment using simulations. The study considers the directional and omnidirectional propagation characteristics and presents a statistical model; the model parameters were derived from ray tracing simulation in an indoor environment, including path loss exponents (PLE), delay spread, the number of clusters, the number of rays per cluster, the cluster power, the cluster and subpath power, intra and inter delay excess delay and the number of the direction of arrival spatial lobes at 245 GHz in both line-of-sight (LOS) and Non-LOS (NLOS) propagation scenarios. The Wireless InSite (WI) software was used for simulations using the shoot and bouncing rays (SBR) technique. The recorded received signal strength (RSS) and path loss (PL) are validated comparatively against WinProp software results using the dominant path model (DPM). A good agreement between the two techniques is demonstrated.

Background Dental caries also known as cavities are the most predominant disease today. Streptococcus mutans can form a biofilm on the tooth surface, produce high levels of lactic acid following fermentation of dietary sugars, and are resistant to the adverse effects of low pH, properties which are essential for oral micro biota. The aim of this study was to isolate S. mutans and characterize their antimicrobial properties against sodium fluoride. Fresh dental caries samples were collected from diabetic patients. The isolates were identified based on their acidogenic, biochemical test, and antimicrobial properties. Methods The socio-demographic data collected through a structure designated questionnaire and the biological data collected through sterile cotton swabs. For analysis of data, Statistical Package for Social Sciences software, version 23.0 (IBM SPSS Inc., Chicago, IL) was used. Results Only 32 of the 80 samples (40%) gave a positive growth for S. mutans on MSBA (mitis salivarius bacitracin agar). The sensitivity of the isolates against sodium fluoride was tested by preparing NaF of four different concentrations (80, 125, 250, and 500) mg\L. Fifty percent of isolates were found to be resistant to NaF at a concentration of 80 mg/L, while 28% were resistant to 125 mg/L NaF, 16% to 250 mg/L and 3% to 500mg/L NaF. The majority of the participants were aged between 51–60 years (33%), were female (54%), had type II diabetes mellitus (64%), and the duration of their diabetes was less than five years (35%). Conclusions By using the information in this study, we were able to discover strains of S. mutans that are resistant to fluoride. This study can be used as an essential key to study the genetic mutation that occurred.

Rabbit hemorrhagic disease is a contagious viral disease of rabbits controlled by vaccination. The present study was aimed to diagnose rabbit hemorrhagic disease from 11 infected farms from Qalubia governorate during 2019 and to prepare homologous vaccine against rabbit hemorrhagic disease virus 2. For this purpose, 11 liver samples were collected from suspected cases and subjected to detection and identification of circulating rabbit hemorrhagic disease virus. Ten samples were confirmed to be rabbit hemorrhagic disease virus using hemagglutination test, animal inoculation and reverse transcriptase polymerase chain reaction. Sequencing and phylogenetic analysis of two isolates (R5&R6) revealed the presence of rabbit hemorrhagic disease virus 2 (A/Qalubia/2019 and B/Qalubia/2019) under accession number MT07629 and MT067630 respectively. The inactivated rabbit hemorrhagic disease virus vaccines were prepared using Montanide ISA 206 oil or aluminum hydroxide gel adjuvants. Prepared vaccines were inoculated subcutaneously in susceptible rabbits and submitted to sterility, safety and potency tests. Obtained results showed that mean hemagglutination inhibition titer for aluminum hydroxide gel vaccine was 6,7.7,8.9 and 9.1 log2 while, Montanide vaccine reached to 6.7,8.7,9.2 and 9.5 log2 at 1st, 2nd, 3rd, and 4th weeks post vaccination, respectively. Immunized rabbits with Montanide vaccine showed better protection reach to 70%, 90%, 100% and 100% when compared to aluminum hydroxide gel vaccine 60%, 70%, 90% and 90% at 1st, 2nd, 3rd and 4th weeks post vaccination respectively. It was concluded that newly emerged rabbit hemorrhagic disease virus 2 was isolated from suspected cases. The two prepared vaccines were sterile, safe and potent. The oily adjuvanted rabbit hemorrhagic disease virus 2 vaccine stimulated an earlier and higher humoral immune response than the aluminum hydroxide gel adjuvanted vaccine. This humoral immune response achieved significant level of protection.

Aim: The present study was aimed to establish a protocol for the evaluation of the in vitro potency of commercial inactivated Newcastle disease virus (NDV) oil-adjuvanted vaccines using hemagglutination test (HA) and blocking ELISA (B-ELISA) based on polyclonal antibodies. Materials and Methods: Aqueous phases from a total of 47 batches of inactivated NDV vaccines manufactured by 20 different companies were extracted with isopropyl myristate. The viral antigen in each sample was detected and quantified by a standard HA test and a B-ELISA assay. To verify the efficiency of the antigen extraction method used in the batches which showed HA and to test the validity of using in vitro antigen quantification by HA and B-ELISA tests, a subset of 13 batches (selected from the total 47 batches) was inoculated in groups of 3-4-week-old specific pathogen-free chickens using the recommended vaccine dose. The immunogenicity of the selected vaccine batches was assessed by the NDV-hemagglutination inhibition antibody titers in individual serum samples collected 4 weeks after vaccination. Further, the efficacy of the vaccines and their protection rates were determined by a challenge test carried out for the vaccinated chickens with the Egyptian 2012 isolate of the virulent NDV genotype VII. Results: A strong correlation was observed between HA titers and B-ELISA mean titers in the tested 47 batches (R2=0.817). This indicated the possibility of using the latter in vitro assays for vaccine potency assessment. The recommended protective NDV antigen titer measured by B-ELISA was determined to be 28 ELISA units per dose. The comparison between the HA titers of the aqueous extracts of test vaccines and the corresponding results of in vivo potency assays (i.e., immunogenicity and efficacy), including antibody titers in the serum of vaccinated birds, indicated that the efficiency of the antigen extraction used may interfere with obtaining a strong correlation between the in vitro and in vivo results. Conclusion: HA or B-ELISA tests can be used as rapid and cost-effective alternatives to traditional in vivo potency tests for vaccine potency assessment by quantifying the NDV antigen present in aqueous phase extracts of the tested vaccines. The latter in vitro protocol, however, requires efficient extraction of the antigen to be able to obtain good correlation with the traditional in vivo potency tests.

أجريت هذه الدراسة على نباتات الورد النامية في مدينة البيضاء عام 2016 بهدف حصر الأمراض الفطرية على أوراق نبات الورد النامي بمدينة البيضاء، أوضحت نتائج الدراسة أن شجيرات الورد المزروعة في الحدائق العامة كانت الأعلى اصابة معنوياً مقارنة بالحدائق المنزلية والمشاتل، ويظهر من هذه النتائج أن كمية المرض على أوراق الورد المزروع بالبيضاء كانت عالية خلال فترة الدراسة، كانت الحدائق المنزلية والمشاتل أقلها اصابة ( 45.5% و 48.3%) على التوالي. مقارنة بالحدائق العامة (73%)،الأمراض التي سجلت في هذه الدراسة كانت: البياض الدقيقي،الصدأ، البقعة السوداء، والبقعة الفضية، احتراق الحواف، واللطخة؛ أكثر الأمراض تواجداً هو مرض البياض الدقيقي حيث بلغ (46.9% و 30.4%) لكل من نسبة الإصابة وشدتها على أوراق الورد المزروعة بمدينة البيضاء على التوالي، بينما مرض الصدأ كان أقل الأمراض المسجلة بالمنطقة خلال سنة 2016 بنسبة اصابة لم يتجاوز متوسطها 4.1%. مع عدم وجود فروق معنوية بين الاتجاهات النبات وإن نسبة الإصابة تتراوح بين 37.5-40%، وكان شهر يوليو هو أعلى الشهور إصابة، وأن أوراق الورد المسنَّة هي الأعلى نسبة أصابة في جميع شهور الدراسة.

Aim: This cross-sectional study was conducted from April to July 2012 in Khartoum state, Sudan, to determine the seroprevalence of brucellosis in goats and to investigate potential risk factors associated with this disease. Materials and Methods: A total of 307 serum samples were collected from both sexes of goats in four different localities and were subjected to testing for brucellosis using rose bengal plate test (RBPT), serum agglutination test (SAT), and competitive enzyme-linked immunosorbent assay (cELISA). Results: The overall seroprevalence was 11.4% (n=35) with a 95% confidence interval (CI) ranging from 7.80 to 15.0. Out of these 35 RBPT-positive samples, the positivity of 18 and 17 were confirmed by SAT and cELISA, respectively. A significant statistical variation was observed between brucellosis seroprevalences in goats purchased from local animal markets and goats that were raised at the farm. Conversely, such significant variations were not observed among the categories of other risk factors with seroprevalences ranging from 3.0% (95% CI between 0.40 and 7.20) to 16.3% (95% CI between 10.4 and 22.3). Location (χ2=9.33, df=3, p=0.02), breed (χ2=3.52, df=1, p=0.05), herd size (χ2=6.59, df=2, p=0.03), and herd expansion (χ2=5.39, df=1, p=0.02) were associated with RBPT-positive status for brucella in the two-tailed Chi-square test. In addition, Sharq an-Nil locality and goats raised at the farm had increased odds of being RBPT positive. Conclusion: Brucellosis was detected in goats in all surveyed localities. An effort should be made to educate goat owners/herders about brucellosis as well as about the importance of vaccination.

1. The effectiveness of inactivated vaccines depends on selecting the suitable adjuvant for vaccine formulation. The potency of vaccines with low antigen content can be improved with the appropriate adjuvant. This could allow production of more doses and lower the production cost. 2. This study evaluated the efficiency of vaccines prepared using oil extracted from natural sources including argan oil, almond oil, sesame seed oil, pumpkin oil, cactus oil and black seed oil as alternative adjuvants for improving the protection capacity of inactivated influenza virus vaccine as compared to commonly used mineral oils. 3. Each vaccine formulation was evaluated for stability, safety and immunogenicity in chickens, as well as for reducing the viral shedding after challenge infection. 4. The cactus, sesame and pumpkin seed oil-based vaccines were found to be potent and successfully induced the production of humoral immunity in vaccinated chickens. [ABSTRACT FROM AUTHOR]

The H9N2 subtype of avian influenza A virus (aIAV) is circulating among birds worldwide, leading to severe economic losses. H9N2 cocirculation with other highly pathogenic aIAVs has the potential to contribute to the rise of new strains with pandemic potential. Therefore, rapid detection of H9 aIAVs infection is crucial to control virus spread. A qualitative reverse transcription recombinase polymerase amplification (RT-RPA) assay for the detection of aIAV subtype H9N2 was developed. All results were compared to the gold standard (real-time reverse transcription polymerase chain reaction (RT-PCR)). The RT-RPA assay was designed to detect the hemagglutinin (HA) gene of H9N2 by testing three pairs of primers and a probe. A serial concentration between 106 and 100 EID50 (50% embryo infective dose)/mL was applied to calculate the analytical sensitivity. The H9 RT-RPA assay was highly sensitive as the lowest concentration point of a standard range at one EID50/mL was detected after 5 to 8 min. The H9N2 RT-RPA assay was highly specific as nucleic acid extracted from H9 negative samples and from other avian pathogens were not cross detected. The diagnostic sensitivity when testing clinical samples was 100% for RT-RPA and RT-PCR. In conclusion, H9N2 RT-RPA is a rapid sensitive and specific assay that easily operable in a portable device for field diagnosis of aIAV H9N2.

Aim: The objective of the present study was to prepare a trivalent inactivated vaccine of Newcastle disease virus (NDV), H5N1, and H9N2 viruses. Materials and Methods: Three monovalent and a trivalent vaccines were prepared by emulsifying inactivated NDV (LaSota strain), reassortant H5N1, and H9N2 viruses with Montanide ISA 71 oil adjuvant. Parameters used for evaluation of the efficacy of the prepared vaccines in specific pathogen-free chickens were cellular immunity assays (blastogenesis, interferon gamma, interleukin 1 [IL1], and IL6), humoral immunity by hemagglutination inhibition, protection percentage, and shedding. Results: A single immunization with trivalent vaccine-enhanced cell-mediated immunity as well as humoral immune response with 90% protection against challenges with highly pathogenic avian influenza (HPAI) H5N1 and low pathogenic (LP) avian influenza H9N2 viruses with 100% protection after challenge with NDV. Conclusion: Development and evaluation of the trivalent vaccine in the study reported the success in preparation of a potent and efficacious trivalent vaccine which is a promising approach for controlling HPAI H5N1, LP H9N2, and ND viral infections.

This study aimed to determine the prevalence of H. pylori infections among schoolchildren and investigate the associations between H. pylori seropositivity and existence of gastrointestinal symptoms. Methods. A prospective cross-sectional study was conducted during a period from January to December 2012 at Kassala state, east of Sudan. Schoolchildren from different primary schools were enrolled in the study. Sociodemographic characteristics and gastrointestinal symptoms were recorded from each child. A rapid immunochromatographic test was performed for the detection of H. pylori IgG antibodies. Data on patient demographic characteristics, clinical diagnosis, and findings of H. pylori infection were analyzed by simple descriptive statistics. Results. Among 431 schoolchildren, H. pylori seropositivity was found to be 21.8%. The majority of children (79; 84%) had BMI below the normal range. The most frequent symptoms associated with H. pylori infections were nausea (25.5%), followed by gastric pain (24.5%) and heart pain (20.2%). There were statistically significant differences in H. pylori seropositivity between boys and girls (p=0.003). Conclusions. The prevalence of H. pylori infection among schoolchildren in Kassala city has been documented. Although the majority of the disease was associated with several gastrointestinal symptoms, the role of infection in the etiology of abdominal symptoms needs further investigations.

In Egypt, two distinct genetic groups of HPAI H5N1 viruses are co-circulating: classic 2.2.1/C sub-clade and antigenic drift variant 2.2.1.1 clade isolated from vaccinated poultry flocks. The response of chicken innate immunity to both genotypes is not investigated, so far. In this study, expression of immune related genes (IL1b, IL4, IL6, IL8, IL10, IL18, IFNα and IFNγ) after infecting chicken macrophage cell line (HD11) and chicken peripheral blood Mononuclear cells (PBMC) with a classic and a variant strains was assayed using quantitative reverse-transcription real-time polymerase chain reaction assays (qRT-PCR). In HD11, the variant strain induced higher levels of IL1b and IL8 at 6 hours post infection (hpi), IL4 at 24 / 48 hpi and IFNα at 48 hpi than the classic strain. Conversely, the classic strain induced about 10-fold increase of IFNγ at 24 and 48 hpi and the virus replicated at higher level than the variant strain. The results of PBMC infection were similar to that reported from HD11 except for IFNγ gene expression that was higher at variant strain infected cells than that infected with the classic strain. After 24hpi skewing the innate immune response toward anti-inflammatory (humoral-associated) cytokines was different between HD11 (through IL4) and PBMC (through IL10). To sum up, the classic strain produced less cytokines which may indicate adaptation to evade the recognition by the innate immune system and explain its higher pathogenicity.

This study identified nontuberculous mycobacteria (NTM) recovered from bovine pyogenic affections obtained at necropsy using the molecular target 16S-23S rDNA internal transcribed spacer region. Postmortem inspection of cattle was conducted at South Darfur State abattoirs and Alsabalouga Slaughterhouse at Omdurman area during 2007-2009. Specimens were examined for the presence of acid fast bacteria (AFB) using microscopic and standard culturing techniques. AFB were identified phenotypically and confirmed by 16S-23S rDNA ITS. Fifty nine NTM were recovered and confirmed as acid fast filaments out of 165 positive AFB specimens, of which 52 isolates were identified as bovine farcy causative agents, while 7 cultures were excluded due to drying. 16S-23S rDNA ITS of NTM revealed three different amplicons 500 bp. (32) isolates, 550 bp. (2) isolates and 600 bp. (14) isolates. Four isolates were contaminated.

One of the major problems of avian infectious bronchitis virus (IBV) is the frequent emergence of new variants. In the present study 205 tracheal swabs and organs were collected from broilers and layers chicken farms during January to August 2012 from 19 governorates all over Egypt. The chickens demonstrated respiratory signs and mortality. Out of the examined samples, 130 of which (about 64%) of suspected farms were positive for IBV with real time RT-PCR. 13 IBV-positive samples were selected for further isolation and characterization. Isolation in specific pathogen free (SPF) embryos was carried out after studies three blind successive passages and the hypervariable region of spike protein1 (SP1) was amplified by RT-PCR and sequenced to study the genetic diversity between the isolated viruses. Phylogenetic analysis of the obtained sequences of 13 isolates compared with other IBV strains from the Middle East and worldwide reveled that 11 out of the 13 isolates had close relationship the Israeli variants (IS/885 and IS/1494/06) with nucleotide homology reached up to 89.9% and 82.3%, respectively. Only two isolates had close relationship with CR/88121 and 4/91 viruses with identities of 95% and 96%, respectively. This study indicates existence of two variant groups of IBV circulating in Egypt during 2012. Group I was similar but distinguishable from Israeli variant IS/885 and group II was related to 4/91 and CR/88121 vaccine strains. There was no geographical link between the 2 groups as they were distributed all over the country. These findings necessitate the need to revise the vaccination programs and control measures for IBV.

Male erectile dysfunction (ED) is an important issue worldwide occurring in 5-69% of men in community-based studies. It is more common in patients with chronic kidney disease (CKD) and those on peritoneal as well as hemodialysis (HD), occurring in more than 80% of patients. In Sudan, there is no pre-vious report on ED among patients with CKD. A cross-sectional study was done to determine the prevalence of ED and its associated risk factors among Sudanese CKD patients on HD and those who underwent renal transplant. This was conducted in Khartoum, Sudan from October 2005 to July 2006 including all married men who were on maintenance HD for more than three months and all married men who had received renal transplantation at least three months earlier. Single, divorced/separated men, those whose wives were living away, those who were bed-bound and those with cognitive impairment were also excluded. After obtaining consent for participation, demographic and clinical data were collected by using anonymous questionnaires and the Arabic version of International Index of Erectile Function (IIEF; the Egyptian version). Patients who did not participate in full and proper manner were considered as "non-responders." A total of 146 patients, 106 HD patients, and 40 renal transplant recipients completed the IIEF questionnaire. Non-responders constituted 43.7% and 54.5% of HD and transplant recipient patients, respectively. Blood samples were taken after completion of the IIEF questionnaire to determine the required investigations. ED prevalence was high among our study patients, 83% among the HD patients and 67.5% among the renal transplant recipients. Univariate analysis showed that there was a trend, although non-significant, of older age being associated with ED in both groups. Similar association was seen in those who were under-dialyzed in the HD group and DM in the transplant recipient group. Previous history of ED was significantly associated with current presence of ED in both groups. More studies with larger sample size are needed to clarify the results of this study.