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result(s) for
"Abdullah, Bashar"
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Granulomatous Lesions in the Head and Neck Region: A Clinicopathological, Histochemical, and Molecular Diagnostic Study
2025
Background/Objectives: Granulomatous lesions of the head and neck arise from diverse infectious and non-infectious causes, with tuberculosis (TB) being a predominant etiology. This retrospective study analyzed 42 cases from the archives of university of Baghdad, College of Dentistry (1975–2025). This study aimed to characterize the clinicopathological features of these lesions and to assess the diagnostic performance of histochemical stains and real-time PCR in identifying infectious etiologies—particularly Mycobacterium tuberculosis—in formalin-fixed, paraffin-embedded (FFPE) tissue samples. Methods: Definitive diagnoses included 25 TB cases confirmed through clinical, microbiological, and therapeutic follow-up at the Baghdad Tuberculosis Institute, and 17 non-TB cases classified by predefined clinicopathological criteria supported by relevant clinical data. Zieh–Neelsen (ZN), Periodic acid–Schiff (PAS), and Grocott methenamine silver (GMS) stains were employed to identify acid-fast bacilli and fungal organisms. Statistical analysis was performed using SPSS version 26, with significance set at p ≤ 0.05. Results: The mean patient age was 36.28 years (SD = 20.6), with a female predominance (59.5%). Necrotizing granulomas were identified in 69% of cases and were strongly associated with tuberculosis, which was detected in 59.5% of specimens. ZN staining showed a sensitivity of 16.7% for tuberculosis, while PCR sensitivity was highly dependent on sample age. The detection rate was 33.3% in samples archived for less than 10 years but only 10% in older samples, resulting in an overall sensitivity of 24.0% for tuberculous cases. Langhans-type giant cells were significantly more frequent in necrotizing granulomas and strongly associated with tuberculosis infection (p = 0.001). Fungal infections, predominantly aspergillosis, were confirmed by PAS and GMS in 11.9% and 9.5% of cases, respectively, and were confined to non-necrotizing granulomas. The mandible was the most commonly affected site, and soft tissue lesions were significantly associated with necrotizing granulomas (p = 0.004). Conclusions: These findings underscore the complementary role of histopathology, histochemical stains, and molecular diagnostics in improving the evaluation and diagnosis of granulomatous inflammation in head and neck lesions.
Journal Article
Hydrolysis optimization and characterization study of preparing fatty acids from Jatropha curcas seed oil
2011
Abstract Background: Fatty acids (FAs) are important as raw materials for the biotechnology industry. Existing methods of FAs production are based on chemical methods. In this study potassium hydroxide (KOH)-catalyzed reactions were utilized to hydrolysis Jatropha curcas seed oil. Results: The parameters effect of ethanolic KOH concentration, reaction temperature, and reaction time to free fatty acid (FFA%) were investigated using D-Optimal Design. Characterization of the product has been studied using Fourier transforms infrared spectroscopy (FTIR), gas chromatography (GC) and high performance liquid chromatography (HPLC). The optimum conditions for maximum FFA% were achieved at 1.75M of ethanolic KOH concentration, 65°C of reaction temperature and 2.0 h of reaction time. Conclusions: This study showed that ethanolic KOH concentration was significant variable for J. curcas seed oil hydrolysis. In a 18-point experimental design, FFA% of hydrolyzed J. curcas seed oil can be raised from 1.89% to 102.2%, which proved by FTIR and HPLC.
Journal Article
Synthesis, reactivity and application studies for different biolubricants
2014
Vegetable oils have different unique properties owing to their unique chemical structure. Vegetable oils have a greater ability to lubricate and have higher viscosity indices. Therefore, they are being more closely examined as base oil for biolubricants and functional fluids. In spite of their many advantages, vegetable oils suffer from two major drawbacks of inadequate oxidative stability and poor low-temperature properties, which hinder their utilization as biolubricant base oils. Transforming alkene groups in fatty acids to other stable functional groups could improve the oxidative stability, whereas reducing structural uniformity of the oil by attaching alkyl side chains could improve the low-temperature performance. In that light, the epoxidation of unsaturated fatty acids is very interesting as it can provide diverse side chains arising from the mono- or di-epoxidation of the unsaturated fatty acid. Oxirane ring opening by an acid-catalyzed reaction with a suitable reagent provides interesting polyfunctional compounds.
Journal Article
Polyesters Based on Linoleic Acid for Biolubricant Basestocks: Low-Temperature, Tribological and Rheological Properties
by
Huri, Hasniza Zaman
,
Hairunisa, Nany
,
Abdullah, Bashar Mudhaffar
in
Acids
,
Acylation
,
Biodegradability
2016
Presently, plant oils which contain high percentage of linoleic acid 1 are perceived to be a viable alternative to mineral oil for biolubricant applications due to their biodegradability and technical properties. In order to get biodegradable lubricant, triester derivatives compounds (1-5) were synthesized and characterized. The processes involved were monoepoxidation of linoleic acid 2, oxirane ring opening 3, esterification 4 and acylation 5. The structures of the products were confirmed by FTIR, 1H and 13C-NMR and LC-MS. The results that showed lowest temperature properties were obtained for triester 5, with a pour point value (PP) of -73°C, highest onset temperature (260°C) and lowest volatility at 0.30%. Viscosity index (VI) increased for the ester's synthetic compounds (2, 3, 4, 5), while the PP decreased. This behavior is the result of the increase of the chain length of the branching agents. Triester based linoleic acid has improved properties such as low-temperature and tribological properties. These results will make it feasible for plant oil to be used for biolubricants, fuels in chain saws, transmission oil and brake fluid.
Journal Article
Comparative Immunohistochemical Analysis of Craniopharyngioma and Ameloblastoma: Insights into Odontogenic Differentiation
2024
Background and objectives: Histopathological similarities between craniopharyngioma (CP) and ameloblastoma (AB) have long been recognized, particularly the shared features of palisading columnar epithelium and stellate reticulum-like areas. This study aimed to investigate potential odontogenic differentiation in CP akin to AB using immunohistochemical odontogenic markers. Methods: We analyzed AMELX, ODAM, and CK19 expression in 44 cases (20 CP and 24 AB). Results: While AMELX and ODAM showed diffuse strong positive expression in both tumors with no significant statistical differences, CK19 expression was notably higher in CP. Conclusion: The markers AMELX and ODAM associated with odontogenic differentiation exhibited similar profiles in both tumors due to shared similar embryological origins. Notably, CK19, a biomarker of odontogenic epithelium, showed even higher expression, suggesting distinct pathways. These findings offer insights into tumor biology and may aid in diagnostic and therapeutic approaches.
Journal Article
Immunohistochemical expression of angiotensin‐converting enzyme 2 in superficial and deep maxillofacial tissues: A cross‐sectional study
2022
Background and Aims The involvement of maxillofacial tissues in SARS‐CoV‐2 infections ranges from mild dysgeusia to life‐threatening tissue necrosis, as seen in SARS‐CoV‐2‐associated mucormycosis. Angiotensin‐converting enzyme 2 (ACE2) which functions as a receptor for SARS‐CoV‐2 was reported in the epithelial surfaces of the oral and nasal cavities; however, a complete understanding of the expression patterns in deep oral and maxillofacial tissues is still lacking. Methods The immunohistochemical expression of ACE2 was analyzed in 95 specimens from maxillofacial tissues and 10 specimens of pulmonary alveolar tissue using a semiquantitative immunohistochemical scoring procedure, taking into account all superficial and deep maxillofacial tissue cells. We also explored the associations of age, gender, and anatomical site with expression scores. Results ACE2 was detected in keratinized epithelia (57.34%), non‐keratinized epithelia (46.51%), nasal respiratory epithelial cells (73.35%), pulmonary alveolar cells (82.54%), fibroblasts (63.69%), vascular endothelial cells (58.43%), mucous acinar cells (59.88%), serous acinar cells (79.49%), salivary duct cells (86.26%) skeletal muscle fibers (71.01%), neuron support cells (94.25%), and bone marrow cells (72.65%). Age and gender did not affect the expression levels significantly in epithelial cells (p = 0.76, and p = 0.7 respectively); however, identical cells expressed different protein levels depending on the site from which the specimens were obtained. For example, dorsal tongue epithelia expressed significantly lower ACE2 scores than alveolar epithelia (p < 0.001). A positive correlation was found between ACE2 expression in fibroblasts and epithelial cells (r = 0.378, p = 0.001), and between vascular endothelial and epithelial cells (r = 0.395, p = 0.001). Conclusion ACE2 is expressed by epithelial cells and subepithelial tissues including fibroblasts, vascular endothelia, skeletal muscles, peripheral nerves, and bone marrow. No correlation was detected between ACE2 expression and patient age or sex while the epithelial expression scores were correlated with stromal scores.
Journal Article
Comparison between neural network and P&O method in optimizing MPPT control for photovoltaic cell
by
Abdullah, ِِِAhmed G.
,
Aziz, Mothanna sh
,
Hamad, Bashar Abdullah
in
Clean energy
,
Control methods
,
Maximum power tracking
2020
The demand for renewable energy has increased because it is considered a clean energy and does not result in any pollution or emission of toxic gases that negatively affect the environment and human health also requiring little maintenance, and emitting no noise, so it is necessary to develop this type of energy and increase its production capacity. In this research a design of maximum power point tracking (MPPT) control method using Neural Network (NN) for photovoltaic system is presented. First we design a standalone PV system linked to dc boost chopper with MPPT by perturbation and observation P&O technique, and then a design of MPPT by using ANN for the same system is presented. Comparative between two control methods are studied. The results explained in constant and adjustable weather settings such as irradiation and temperature. The results exposed that the proposed MPPT by ANN control can improve the PV array efficiency by reduce the oscillation around the MPP that accure in P&O method and so decreases the power losses. As well as decrease the the overshot that accure in transient response, and hence improving the performance of the solar cell.
Journal Article
Biological mechanisms and therapeutic prospects of interleukin-33 in pathogenesis and treatment of allergic disease
by
Ahmad, Fuzail
,
Mohamed, Asma’a H.
,
Kamal, Mohammad Azhar
in
Allergic diseases
,
Allergology
,
Antigens
2025
Allergic diseases significantly impact the quality of life of people around the world. Cytokines play a crucial role in regulating the immune system. Due to their importance in pro-inflammatory mechanisms, cytokines are used to understand pathogenesis and serve as biomarkers in many diseases. One such cytokine is interleukin-33, a member of the IL-1 family, including IL- 1α, IL-1β, and IL-18. The IL-33 receptor is a heterodimer of IL-1 receptor-like 1 and IL-1 receptor accessory protein. IL-33 plays a critical role in regulating innate and adaptive immune responses. The primary targets of IL-33 in vivo are tissue-resident immune cells, including mast cells, group 2 innate lymphoid cells, regulatory T cells, T helper 2 cells, eosinophils, basophils, dendritic cells, Th1 cells, CD8 + T cells, NK cells, iNKT cells, B cells, neutrophils, and macrophages. However, IL-33 appears to act as an alarm signal that is promptly released by producing cells under cellular damage or stress conditions. IL-33 regulates signaling and various biological functions, including induction of pro-inflammatory cytokines, regulation of cell proliferation, and involvement in tissue remodeling. IL-33 is fundamental in immune-related diseases and plays a critical role in the control of inflammation. Recently, IL-33 has been shown to significantly impact allergic diseases, primarily by inducing Th2 immune responses. IL-33 is a key regulator of mast cell function and a promising therapeutic target for treating allergic diseases. This review provides an overview of the current understanding of the role of IL-33 in allergy pathogenesis and potential clinical approaches.
Journal Article
Bacterial etiology of bloodstream infections and antimicrobial resistance in Dhaka, Bangladesh, 2005–2014
by
Elahi, Md Shahriar Bin
,
Sadique, Tuhin
,
Rana, Md Sohel
in
Antibiotics
,
Antimicrobial resistance
,
Bacteria
2017
Background
Bloodstream infections due to bacterial pathogens are a major cause of morbidity and mortality in Bangladesh and other developing countries. In these countries, most patients are treated empirically based on their clinical symptoms. Therefore, up to date etiological data for major pathogens causing bloodstream infections may play a positive role in better healthcare management. The aim of this study was to identify the bacterial pathogens causing major bloodstream infections in Dhaka, Bangladesh and determine their antibiotic susceptibility pattern.
Methods
From January 2005 to December 2014, a total of 103,679 single bottle blood samples were collected from both hospitalized and domiciliary patients attending Dhaka hospital, icddrb, Bangladesh All the blood samples were processed for culture using a BACT/Alert blood culture machine. Further identification of bacterial pathogens and their antimicrobial susceptibility test were performed using standard microbiological procedures.
Results
Overall, 13.6% of the cultured blood samples were positive and Gram-negative (72.1%) bacteria were predominant throughout the study period.
Salmonella
Typhi was the most frequently isolated organism (36.9% of samples) in this study and a high percentage of those strains were multidrug-resistant (MDR). However, a decreasing trend in the
S
. Typhi isolation rate was observed and, noticeably, the percentage of MDR
S. Typhi
isolated declined sharply over the study period. An overall increase in the presence of Gram-positive bacteria was observed, but most significantly we observed the percentage of MDR Gram-positive bacteria to double over the study period. Overall, Gram positive bacteria were more resistant to most of the commonly used antibiotics than Gram-negative bacteria, but the MDR level was high in both groups.
Conclusions
This study identified the major bacterial pathogens involved with BSI in Dhaka, Bangladesh and also revealed their antibiotic susceptibility patterns. We expect our findings to help healthcare professionals to make informed decisions and provide better care for their patients. Also, we hope this study will assist researchers and policy makers to prioritize their research options to face the future challenges of infectious diseases.
Journal Article
A clinical and demographic analysis of oral pemphigus vulgaris: A retrospective cross‐sectional study from 2001 to 2021
by
Abdullah, Bashar
,
Aswad, Fawaz
,
Alshami, Muhanad L.
in
Autoimmune diseases
,
Biopsy
,
Chi-square test
2022
Background and Aims Pemphigus vulgaris is an autoimmune vesiculobullous mucocutaneous disorder with life‐threatening consequences. Early detection and adequate care are crucial for a good prognosis. This study aimed to determine the demographic data, clinical features, and the prognosis of patients with oral pemphigus vulgaris. Materials and Methods From 2001 to 2021, all diagnosed oral pemphigus vulgaris cases were extracted. Each patient's demographic and clinical data were gathered. Patients were called via phone to assess the prognosis, treatment type, and specialty of the physician who provided the diagnosis and therapy. Results The majority of the patients had only oral lesions with higher prevalence in female who also expressed severe pain than male. Only 14 of 29 patients responded phone calls. Except for one, all patients were in active disease. More than half of those respondents said pemphigus negatively affects social behavior and food intake. Correct diagnosis and treatment were decided by dermatology, oral medicine, and maxillofacial surgery specialists. Conclusion Oral pemphigus vulgaris was prevalent in females. Severe pain was common in females and older people. Even with effective therapy, the prognosis was poor. Medical and dental professionals had little knowledge of pemphigus vulgaris. Patients frequently report poor quality of life.
Journal Article