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result(s) for
"Hamada, Rania"
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Towards Investigating the Effect of Ammonium Nitrate on the Characteristics and Thermal Decomposition Behavior of Energetic Double Base NC/DEGDN Composite
by
Trache, Djalal
,
Ahmed Hamada, Rania
,
Klapötke, Thomas M.
in
Activation energy
,
Ammonium nitrate
,
Analysis
2022
This research work aimed to elaborate on a new modified double-base propellant containing nitrocellulose (NC), ammonium nitrate (AN), and diethylene glycol dinitrate (DEGDN). The developed AN/NC-DEGDN formulation was successfully obtained through a casting process and fully characterized in terms of its chemical structure, morphological features, and thermal behavior. Beforehand, theoretical calculation by the CEA-NASA program was applied to select the optimal composition of the formulation. Experimental findings demonstrated the homogenous dispersion of AN oxidizer in the NC-DEGDN matrix without alteration of their molecular structures. The catalytic influence of AN on the thermal decomposition behavior of NC-DEGDN film was also elucidated by thermal analyses. When AN was incorporated into the formulation, the decomposition peak temperatures for the different decomposition processes were shifted toward lower temperatures, while the total enthalpy of decomposition increased by around 1272.24 J/g. In addition, the kinetics of the thermal decomposition of the developed modified double base propellant were investigated using DSC results coupled with model kinetic approaches. It was found that the addition of AN decreases the activation energy of nitrate esters from 134.5 kJ/mol to 118.84 kJ/mol, providing evidence for its excellent catalytic effect. Overall, this investigation could serve as a reference for developing future generation of modified double-base propellants.
Journal Article
The influence of risk factors on bovine leukemia virus infection and proviral load in egyptian cattle
2024
Bovine leukemia virus (BLV) is the etiological agent of enzootic bovine leucosis (EBL), which affects cattle globally. In Egypt, BLV control strategies have been ignored because of the shortage of BLV research studies and the silent infection in most animals. This study aimed to identify the risk factors associated with the prevalence of BLV among dairy and beef cattle from six different geographic and climatic provinces in Egypt. Additionally, risk factors affecting the BLV proviral load (PVL) among the positive cattle were targeted. The total BLV prevalence in cattle from six investigated Egyptian provinces was 24.2% (105/433), while the mean PVL (8651.6 copies /105 white blood cells) was absolutely high as estimated by the BLV-CoCoMo-quantitative polymerase chain reaction (qPCR)-2 assay. Analysis of the influence of risk factors (age, sex, breed, production type, farm size, and location) on BLV prevalence indicated that the Holstein breed (OR = 1.582, p = 0.007), beef cattle (OR = 1.088, p = 0.0001), large-size farms (OR = 1.26, p = 0.0001), and cattle from Damietta (OR = 1.43, p = 0.0001) and Cairo (OR = 1.16, p = 0.0001) were ultimately proven the most important risks for BLV infection. The risk factors were analyzed considering the BLV PVL levels in the BLV-positive cases. Significantly high PVL (HPVL) levels were observed in cattle > 5 years old (p < 0.0001), females (p = 0.0008), Holstein (p < 0.0001), dairy cows (p = 0.0053), large-size farms (p < 0.0001), and cattle from Damietta (p < 0.0001) compared to other categories. Contrary, no significant differences in PVL levels were reported between the Native and Mixed cattle breeds (p = 0.13). Ultimately, the logistic regression model indicated that the probability of carrying HPVL in cattle > 5 years is 1.27 (95% CI: 1.03–2.09, p < 0.001) times more likely compared to cattle < 2 years old. In conclusion, the findings were valuably correlating the BLV prevalence with PVL as an indicator of the risk of BLV infection.
Journal Article
Combination of approved chemotherapeutics and natural products for topoisomerase II targeting: efficacy and safety in cancer therapy
by
Hamada, Rania
,
Fu, Junjiang
,
El-Far, Ali H.
in
Antibiotics
,
Anticancer potential
,
Breast cancer
2025
Cancer is characterized by abnormal cell growth and remains a leading global cause of death despite advances in conventional therapies. Limitations such as lack of selectivity, cytotoxic side effects, and multidrug resistance underscore the need for potent anticancer agents. Topoisomerase II (TOP2) has emerged as a pivotal target for anticancer drugs, categorized as poisons and catalytic inhibitors. While clinically used TOP2-based drugs predominantly act as poisons, concerns regarding their cytotoxicity and DNA-damaging potential persist. In response to these challenges, exploring natural bioactive compounds (NBCs), including small molecules from Chinese herbs, as sources of novel anticancer agents has become a focal point in pharmaceutical research. Recognizing that NBCs alone may not satisfy as anticancer agents, this review aims to comprehensively analyze the current published studies, specifically focusing on the combined applications of TOP2-inhibiting approved chemotherapeutics and natural products. The review explores this approach's potential synergies and challenges, emphasizing the importance of developing effective and targeted anticancer strategies.
Journal Article
Seroprevalence and risk factors analysis of Neospora caninum and Toxoplasma gondii in cattle of Beheira, Egypt
2023
and
are closely related obligate intracellular protozoan parasites. They are considered to be the major causes of infectious abortions and congenital abnormalities in livestock worldwide resulting in huge economic losses. Currently, there are no reports on the prevalence of neosporosis or toxoplasmosis in cattle in Beheira, Egypt's most important region for cattle industry.
The current study investigated the presence of anti-
and anti-
antibodies in apparent healthy cattle from eight localities representing the whole area of Beheira. A total of 358 plasma samples were randomly collected from 6 dairy and 10 beef farms and analyzed by commercially available ELISAs. Production type (dairy versus beef), sex (female vs male), age (< 3 years, 3-5, and > 5 years old), breed (mixed vs Holstein vs Colombian Zebu), and location (various locations) were assessed as risk factors for
and
infections.
Of the samples, 88 (24.6%) and 19 (5.3%) were positive for anti-
and anti-
antibodies, respectively, and mixed infection was detected in 7. Of the 16 herds, 6 dairy and 7 beef herds were positive for antibodies to
. Antibodies to
were detected in 4, and 5 of dairy and beef herds, respectively. Production type (dairy) and, therewith, sex (female), age (aged over 5 years), and location were considered as risk factors for
infection. No factors statistically associated with
infection were identified. Overall, this study provided the first serological detection of
and
infections in cattle from Beheira, demonstrating the endemicity of both parasites in the main cattle rearing region of Egypt. This study also confirmed earlier reports of
being more present in dairy cattle than in beef cattle. Routine monitoring of
and
infections and the implementation of control strategies are urgently needed.
Journal Article
Association between biochemical parameters and ultrasonographic measurement for the assessment of hepatic lipidosis in dairy cows
by
Hamada, Rania
,
Elshafey, Besheer G.
,
Mandour, Ahmed S.
in
3-hydroxybutyric acid
,
Alanine transaminase
,
antioxidant activity
2023
Hepatic lipidosis (HL) is a serious metabolic disorder that affects transient high-producing dairy cows. However, there are many laboratory methods could help in the assessment of HL in dairy cows, the definite diagnosis of the disease under field conditions remains a challenge because of the non-specificity of clinical parameters. The aim of the study was to investigate the utility of serum biomarkers, and ultrasonography (US) measurement to diagnose HL in dairy cows. Forty Holstein dairy cows underwent physical examination and were divided into three groups: non-HL, mild HL, and severe HL groups based on US findings, and the concentrations of beta-hydroxybutyric acid (BHBA) and nonesterified fatty acids (NEFAs). Ultrasound images showed hyperechoic lesions and increased pixel intensity (PI) values of liver echotexture in the HL groups. A significant increase was observed in mild and severe HL groups in the activity of serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma-glutamyl transferase (GGT), BHBA, NEFAs, malondialdehyde (MDA), and nitric oxide (NO) while the concentrations of triglyceride (TG), glutathione (GSH), and total antioxidant capacity (TAC) were significantly decreased. The classification accuracy was in the interest of NEFAs (cut off 0.62 mmol/L, sensitivity 82.6%, specificity 91.7%, and an AUC of 0.913) and BHBA (cut off 1.35 mmol/L, sensitivity 91.31%, specificity of 86.4%, and an AUC 0.812) as important diagnostic parameters. This study offers new insights into the importance of serum biochemical parameters and oxidative stress biomarkers especially, AST, NEFAs, BHBA, and GSH with the digital values of US images for prompt use of minimally invasive techniques to diagnose HL under farm conditions.
HIGHLIGHTS
Serum metabolites and oxidative stress indices could diagnose hepatic lipidosis in dairy cows
NEFA and BHBA concentrations and ultrasound digital values can use as a non-invasive way to the classification of hepatic lipidosis degrees in cows under farm condition.
Journal Article
The First Serological Detection and Risk Factors Analysis of Akabane Virus in Egyptian Cattle
by
Samy Metwally
,
Taghreed N. Almanaa
,
Marwa Samir
in
Advertising executives
,
Akabane disease
,
Akabane disease; seroprevalence; ELISA; cattle; Egypt
2023
Akabane virus (AKAV) is an insect-borne virus belonging to the genus Orthobunyavirus of the family Peribunyaviridae. It is the etiologic agent of Akabane disease (AD), which emerged in Asia, Australia, and the Middle East causing severe economic losses among domestic and wild animals. AKAV has not received enough attention in Egypt, and its evidence among Egyptian animals has never been reported. Therefore, this study used ELISA assay to investigate the seroprevalence of AKAV among Egyptian dairy and beef cattle in eight localities of Beheira province, north Egypt. Out of 368 investigated plasma samples, the overall AKAV seroprevalence was 54.3% (95% CI: 50.8–61.4). AKAV antibodies were detected in all examined cattle farms (7/7) and the majority of abattoirs (8/9). Age, sex, breed, and location of the tested cattle were analyzed as risk factors for AKAV infection. A higher significant increase in seropositivity was obtained in cattle who were aged >5 years (p < 0.0001; OR = 9.4), females (p < 0.0001, OR = 8.3), or Holstein breed (p < 0.0001, OR = 22.6) than in younger ages, males, and Mixed and Colombian zebu breeds, respectively. Moreover, a significant variation in AKAV seroprevalence between the tested locations was noticed. Ultimately, a multivariable analysis concluded that age (p = 0.002, OR = 3.32, 95% CI = 1.57–7.04) and breed (p = 0.03, OR = 1.69, 95% CI = 1.05–2.72) were significant risks for AKAV infection. In conclusion, this study is the first to detect AKAV infection in Egyptian animals.
Journal Article
BoLA-DRB3 Polymorphism Associated with Bovine Leukemia Virus Infection and Proviral Load in Holstein Cattle in Egypt
2023
Bovine leukemia virus (BLV) is the etiological agent of enzootic bovine leukosis, the most prevalent neoplastic disease of cattle worldwide. The immune response to BLV and disease susceptibility and resistance in cattle are strongly correlated with the bovine leukocyte antigen (BoLA)-DRB3 allelic polymorphism. BLV infection continues to spread in Egypt, in part because the relationships between BLV infection, proviral load in Egypt, and BoLA-DRB3 polymorphism are unknown. Here, we identified 18 previously reported alleles in 121 Holstein cows using a polymerase chain reaction sequence-based typing method. Furthermore, BoLA-DRB3 gene polymorphisms in these animals were investigated for their influence on viral infection. BoLA-DRB3*015:01 and BoLA-DRB3*010:01 were identified as susceptible and resistant alleles, respectively, for BLV infection in the tested Holsteins. In addition, BoLA-DRB3*012:01 was associated with low PVL in previous reports but high PVL in Holstein cattle in Egypt. This study is the first to demonstrate that the BoLA-DRB3 polymorphism confers resistance and susceptibility to PVL and infections of BLV in Holstein cattle in Egypt. Our results can be useful for the disease control and eradication of BLV through genetic selection.
Journal Article
A Newly Emerging Serotype A Strain in Foot-and-Mouth Disease Virus with Higher Severity and Mortality in Buffalo than in Cattle Calves in North Egypt
2023
A severe foot-and-mouth disease (FMD) epidemic struck several Egyptian provinces recently, causing significant losses among animals even in vaccinated farms. This study indicated the existence of the newly emerging foot-and-mouth disease virus (FMDV) and first investigated its effect on the Egyptian water buffalo (Bubalus bubalis) and cattle calves in the Beheira province, north Egypt. Twenty tongue epithelial samples from diseased calves in five infected farms were randomly collected, prepared, and propagated using baby hamster kidney-21 (BHK-21) cells. Whole genomic RNA was extracted from the cells of the third passage. A FMDV genome was detected and serotyped using one-step reverse transcription polymerase chain reactions (RT-PCRs). Nucleotide sequencing of the purified serotype-specific PCR bands was performed, and a maximum likelihood phylogenetic tree based on 600 base pairs of VP1 was constructed. The results identified FMDV, serotype A in all infected samples, whereas the serotypes O and SAT2 were negative. The obtained 20 sequences were identical to each other and similar to the newly reported strain in Egypt that belongs to the Europe–South America (Euro–SA) topotype. The epidemiological and clinical parameters associated with such a strain were fully recorded by veterinarians and analyzed in a single infected farm including 70 cattle and buffalo calves. It caused higher peracute mortalities in buffalo (25.7%; 95% CI: 13–43) than in cattle (8.6%; 95% CI: 2–24) calves. Severe clinical signs such as dullness, hypothermia, bradycardia, and cardiac arrhythmia were common to both except in fatal cases, whereas hyperthermia and respiratory signs were prevalent in cattle calves. In conclusion, we first characterized the newly emerging FMDV in the calves of Beheira as more fatal and severe in buffalo than in cattle calves.
Journal Article
Detection and Molecular Characterization of Bovine Leukemia Virus in Egyptian Dairy Cattle
by
Hamada, Rania
,
Ali, Alsagher O.
,
Borjigin, Liushiqi
in
BLV genotype
,
bovine leukemia virus
,
Bovine leukosis
2020
Bovine leukemia virus (BLV) causes enzootic bovine leukosis (EBL), the most common neoplastic disease in cattle worldwide. The first EBL outbreak in Egypt was reported in 1997. To date, there are few studies regarding BLV diagnosis using only serological detection and no studies investigating the distribution of BLV provirus, which is the retroviral genome integrated into the host genome, in Egypt. The genetic characteristics of Egyptian BLV strains are also unknown. Therefore, we aimed to detect BLV provirus and determine BLV genetic variability among dairy cattle in Egypt. We collected 270 blood samples of dairy cattle from 24 farms located in five provinces in Egypt. Out of the 270 samples, 58 (21.5%) were positive for BLV provirus. Phylogenetic analysis based on 18 420-bp selected sequences out of 50 isolates of the BLV env -gp51 gene demonstrated that Egyptian BLV isolates were clustered into genotype-1 and-4, among 11 genotypes detected worldwide. Furthermore, phylogenetic analysis and alignment of the 501-bp sequence of the env- gp51 gene revealed that at least six genetically different strains are present in Egypt. Genotype-1 isolates comprised four different strains (G1-a, G1-b, G1-c, and G1-d) and genotype-4 isolates included two different strains (G4-x and G4-y). Moreover, in one farm with 100% infection rate, we identified three isolates of G1-a strain, 35 isolates of G4-x strain, and two isolates of G4-y strain. Overall, this study provides the new report on molecular prevalence of BLV in Egypt and records the coexistence of BLV genotype-1 and-4 in Egyptian cattle.
Journal Article
Risk Assessment of Bovine Major Histocompatibility Complex Class II DRB3 Alleles for Perinatal Transmission of Bovine Leukemia Virus
by
Lo, Chieh-Wen
,
Inokuma, Michihito
,
Yoneyama, Shuji
in
Alleles
,
Antigens
,
BoLA-DRB3 polymorphism
2021
Perinatal transmission plays a critical role in the spread of bovine leukemia virus (BLV) infection in cattle herds. In the Holstein breed, we previously identified BLV resistant and susceptible bovine leukocyte antigen (BoLA)-DRB3 alleles, including BoLA-DRB3*009:02 and *014:01:01 with a low BLV proviral load (PVL), and *015:01 and *012:01 with a high PVL. Here, we evaluated the perinatal BLV transmission risk in dams with different BoLA-DRB3 alleles. BoLA-DRB3 alleles of 120 dam-calf pairs from five dairy farms in Japan were identified; their PVL was quantified using the BLV-Coordination of Common Motifs (CoCoMo)-qPCR-2 assay. Ninety-six dams were BLV-positive, and 29 gave birth to BLV-infected calves. Perinatal transmission frequency was 19% in dams with resistant alleles suppressed to a low PVL level, and 38% and 25% in dams with susceptible and neutral alleles that maintained high PVL levels, respectively. Notably, all calves with resistant alleles were BLV free, whereas 30% of calves with susceptible genes were infected. Thus, vertical transmission risk was extremely lower for dams and calves with resistant alleles compared to those with susceptible alleles. Our results can inform the development of effective BLV eradication programs under field conditions by providing necessary data to allow for optimal selection of dams for breeding.
Journal Article