استشعار النصاب (Quorum sensing, QS) هو آلية معروفة تستخدمها جراثيم عديدة للسيطرة على عوامل الضراوة الهامة من خلال الإنتاج والاستجابة اللاحقة ل .)N-acylhomoserine (AHLs جرى تسجيل تثبيط استشعار النصاب (QSI) ، الذي يستهدف الإشارات المعتمدة على AHL، كاستراتيجية للسيطرة على الأمراضية الجرثومية. وبالتالي، تهدف هذه الدراسة إلى البحث عن قدرة جرثومة الزائفة الزنجارية كمؤشر للفحص السريع عن QSI المحتمل المتسبب عن المستخلصات النباتية على أساس تثبيط الصبغة. استخدمت أربع مستخلصات نباتية كحولية بضمنها: براعم زهور القرنفل المجففة ( Syzygium aromaticum L)، لحاء القرفة (Cinnamomum cassia L)، أوراق المورينجا (Moringa oleifera Lam)، والقطب (Tribulus terrestris L) وجرى مقارنة قابيلتها على التثبيط QSI)) مع الفيورانون. استخدمت طريقة الانتشار في حفر الهلام، إذ جري تلقيح عزلة الزائفة الزنجارية على وسط الهلام الخاص بـها الذي احتوى على حفر بحجم 8 ملم لتحميل تراكيز مختلفة من المستخلصات النباتية فضلا عن الفيورانون أو محلول الفوسفات الداريء (سيطرة سالبة). أظهرت النتائج نجاح الفيورانون في تثبيط صبغة البايوسيانين للزوائف الزنجارية دون التداخل مع النمو الجرثومي، وهذا يؤكد قدرة هذه العزلة الجرثومية كمؤشر فعال يستدل من خلاله على وجود QS. الأهم من ذلك، سبب مستخلص القرنفل بتراكيز مختلفة في تثبيط تام لصبغة البايوسيانين مع تأثير ضئيل على النمو الجرثومي. عند استخدام القرفة، أظهرت التراكيز العالية فقط تثبي ًطا واض ًحا لصبغة العزلة المستخدمة. تسببت المورينغا أي ًضا في درجة معينة من تثبيط الصبغة ولكن بتراكيز عالية فقط. وعلى العكس من ذلك، لم يؤثر القطب على إنتاج البيوسيانين ولا على الحيوية الجرثومية. يستنتج من هذه الدراسة نجاح عزلة الزائفة الزنجارية المنتجة للبايوسيانين في فحص مثبطات QS. توصي هذه الدراسة البسيطة باستخدام مثل هذه العزلة ككاشف عن QSI دون الاعتماد على استيراد سلالات معينة من جراثيم Chromobacterium violaceum أو Pseudomonas aureofaciens أو Agrobacterium tumefaciens.
PvcABCD are cluster of genes found in Pseudomonas aeruginosa. The research was designed to examine the relationship between the pvc genes expression and cupB gene, which plays a crucial role in the development of biofilm, and rhlR, which regulates the expression of biofilm-related genes, and to investigate whether the pvc genes form one or two operons. The aims were achieved by employing qRT-PCR technique to measure the gene expression of genes of interest. It was found that out of 25 clinical isolates, 21 isolates were qualified as P.aeruginosa. Amongst, 18(85.7%) were evaluated as biofilm producers, 10 (47.6%), 5 (23.8%), and 3 (14.2%) were evaluated as strong, moderate and weak producers respectively, while, 3 (14.2%) were considered
... Show MoreSeeds, beans, leaves, fruit peel and seeds of five plants (Ferula assa-foetida, Coffea robusta, Olea europaea, Punica granatum and Vitis vinifera, respectively) were extracted with four solvents (distilled water, 80% methanol, 80% acetone and a mixed solvent that included methanol, ethanol, acetone and n-butanol at proportions 7:1:1:1). Such manipulation yielded 20 extracts, which were phytochemically analyzed for total polyphenols (TP) and flavonoids (TF). The DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity (RSA) and DPP-4 (dipeptidyl peptidase-4) relative inhibition activity (RIA) were also assessed for each extract. The results revealed that mixed solvent extract of V.
... Show MoreBackground: LasA protease play a major role in the colonization of the bacteria to the cornea during bacterial keratitis by preventing other bacteria from colonization to the cornea, for example in the mixed infection with S. aureus the enzyme eradicate the bacteria by their lysis it and finally eliminate the competitive for P. aeruginosa bacteria.
Objective: To study the role of LasA protease of Pseudomonas aeruginosa in the treatment of experimental keratitis caused by S. aureus.
Patients and methods: One hundred - twenty clinical samples (corneal scraping) were collected from patients suspected with bacterial keratitis presenting to Ibn Al-Haitham Teaching Hospital from May 2013 until November 2013. The bacterial isolate of P. a
Back ground: Epstein- Barr virus (EBV) is a ubiquitous in that infecting more than 90% of adult population worldwide. Recently, EBV has been linked to the development of variety of human malignancies. P53 gene is mutated in more than 50% of human cancers. Cell cycle dysregulation, measured by p53 protein expression, and latent EBV infection are important in the pathogenesis of Non-Hodgkin’s lymphomas.
Objective: To analyze the distribution and impact of concordant p53 expression and latent EBV infection on a group of B & T cell types of NHL.
Materials and Methods: Forty (40) formalin-fixed, paraffin embedded tissue blocks were obtained from lymph nodes biopsies related to patients with NHL.
In addition, biopsies of twenty
The growing use of tele
This paper presents a new secret diffusion scheme called Round Key Permutation (RKP) based on the nonlinear, dynamic and pseudorandom permutation for encrypting images by block, since images are considered particular data because of their size and their information, which are two-dimensional nature and characterized by high redundancy and strong correlation. Firstly, the permutation table is calculated according to the master key and sub-keys. Secondly, scrambling pixels for each block to be encrypted will be done according the permutation table. Thereafter the AES encryption algorithm is used in the proposed cryptosystem by replacing the linear permutation of ShiftRows step with the nonlinear and secret pe
... Show MoreOrganofluorines, as a pollutant, belongs to a group of substances which are very difficult to neutralize. They are part of many products of everyday use and for this reason they pollute the environment in large quantities. Perfluorinated carboxylic acids are entered into the list of the “Stockholm Convention on Persistent Organic Pollutants” in order to minimize the load on the environment by significantly reducing their use, up to their complete rejection. The DD4 strain was isolated from the soil by the enrichment method and identified using 16S rRNA method as Pseudomonas plecoglossicida. It is able to metabolize perfluorooctanoic acid (PFOA) as the only carbon source in Raymond nutrient medium with a concentration of 1000
... Show MoreIn this study, from a total of 856 mastitis cases in lactating ewes, only 34 Streptococcus agalactiae isolates showed various types of resistance to three types of antibiotics (Penicillin, Erythromycin and Tetracycline). St. agalactiae isolates were identified according to the standard methods, including a new suggested technique called specific Chromogenic agar. It was found that antibiotic bacterial resistance was clearly identified by using MIC-microplate assay (dilution method). Also, by real-time PCR technique, it was determined that there were three antibiotics genes resistance ( pbp2b, tetO and mefA ). The high percentage of isolate carried of a single gene which was the Tetracycline (20.59%) followed by percentage Penicillin was
... Show MoreOne hundred and eighty five urine samples were collected eight isolates (4.3%) were obtained and diagnosed as Staphylococcus aureus. Among 8 isolates, 5 (62.5%) S. aureus isolates were found to be enterotoxigenic, most of isolates produced at least two types of Staphylococcal enterotoxins (SEs). The production of enterotoxins in the presence or absence of Thymol extracts (aqueous and alcoholic) were estimated using a reversed passive latex agglutination (SET-RPLA) kit. The extracts reduced enterotoxin production compared with the control. Enterotoxin inhibition was observed for enterotoxin C production at minimal inhibitory concentrations (MIC) at 400 µg/ml, whereas production of enterotoxins A, B, and
... Show MoreIn this research, a variable stiffness actuator is proposed to enhance the damping of the mechanical vibrating system. The frequency response analysis of the vibrating system is dependant in order to analyze and synthesis this semi-active damping, where the suggested process is using active filter to estimate the present frequency of the vibration system, and this will limit the value of the stiffness of the vibrated system. Two active filter s are needed, low-pass-filter (LPF) to choose the higher stiffness of the actuator at small frequencies as well as more damping and high-pass-filter (HPF) to choose the lower stiffness of the actuator at high frequencies as well as more damping, and so
... Show MoreBackground: Clostridium perfringens enterotoxin (CPE), which is one of the most common cause’s foodborne illnesses and contribute to diarrhea that is associated with broadspectrum antibiotic treatment.
Objectives: This study focuses on diagnosis of Clostridium perfringens enterotoxin (CPE) from patients suffering from food poisoning and diarrhea associated with antibiotic treatment cases in stool samples and to determine the resistance of isolated against antibiotics.
Methods: Samples were taken during the period of first of June 2015 until the end of April 2016 from Baghdad hospitals. Enzyme Linked Immunosorbent Assay (ELISA) was used to detect Clostridium perfringens enterotoxin in stool samples. Api 20A kit and culture to conf