Sensitivity and specificity of chest ultrasound in the diagnosis of pulmonary embolism in the emergency department: A case-control study.

Objectives: The present study was designed to evaluate the role of chest ultrasound in the diagnosis of acute pulmonary embolism (PE) and determine its accuracy using multi-detector CT-pulmonary angiography (MD-CTPA) as a gold standard technique for PE diagnosis. Patients and methods: A prospective case-control study was performed with 75 patients who presented to the emergency department of Minia Cardiothoracic University Hospital with clinical suspicion of PE. All patients were evaluated clinically and by laboratory tests to assess the risk of PE. Thoracic ultrasound (TUS) was then performed for all patients for signs suggestive of PE. Finally, MD-CTPA was performed to confirm or exclude the presence of PE. Results: Patients were subdivided into two groups according to the result of MD-CTPA; group I (patients with PE) and group II (control group without PE). In our study, PE was present in the lower lobe in 75% of cases, then in the middle in 13% and in the upper lobe in 3.8% of cases. The majority of lesions in TUS were wedge-shaped lesions. No vascular flow was detected in 83% of PE-confirmed patients. The current study revealed that TUS has 81.25% sensitivity, 95% specificity, 98.3% positive predictive value, 77.2% negative predictive value and 87% accuracy in the diagnosis of PE. Univariate regression analysis revealed that the presence of wedge-shaped pleural-based lesions in grayscale US and the absence of flow signals by colour Doppler sonography (CDS) increase the possibility of PE. Wedge-shaped pleural-based lesions increase the possibility of PE by 1.48 times (P=0.0001), and the absence of flow signals by CDS increases the possibility of PE by 92.89 times (P=0.00001). Multivariate regression analysis revealed that adding absent flow signals by CDS to wedge-shaped pleural-based lesions by grayscale US increases the possibility of a PE diagnosis by 50.28 times (P=0.001). Conclusion: Chest ultrasound is a simple, safe, noninvasive, inexpensive, bedside diagnostic radiological technique that can be used in the emergency department for suspected PE or as an alternative to MD-CTPA when CTPA is contraindicated. Wedge-shaped lesions and the absence of flow signals by CDS increase the diagnostic value of ultrasound for PE.

Anticolitic activity of prodigiosin loaded with selenium nanoparticles on acetic acid-induced colitis in rats.

Ulcerative colitis (UC) is a chronic autoimmune inflammatory disease associated with extensive mucosal damage. Prodigiosins (PGs) are natural bacterial pigments with well-known antioxidant and immunosuppressive properties. In the current study, we examined the possible protective effect of PGs loaded with selenium nanoparticles (PGs-SeNPs) against acetic acid (AcOH)-induced UC in rats. Thirty-five rats were separated into five equal groups with seven animals/group: control, UC, PGs (300 mg/kg), sodium selenite (Na2SeO3, 2 mg/kg), PGs-SeNPs (0.5 mg/kg), and 5-aminosalicylates (5-ASA, 200 mg/kg). Interestingly, PGs-SeNPs administration lessened colon inflammation and mucosal damage as indicated by inhibiting inflammatory markers upon AcOH injection. Furthermore, PGs-SeNPs improved the colonic antioxidant capacity and prevented oxidative insults as evidenced by the upregulation of Nrf2- and its downstream antioxidants along with the decreased pro-oxidants [reactive oxygen species (ROS), carbonyl protein, malondialdehyde (MDA), inducible nitric oxide synthase (iNOS), and nitric oxide (NO] in the colon tissue. Furthermore, PGs-SeNPs protected intestinal cell loss through blockade apoptotic cascade by decreasing pro-apoptotic proteins [Bcl-2-associated X protein (Bax) and caspase-3] and increasing anti-apoptotic protein, B cell lymphoma 2 (Bcl2). Collectively, PGs-SeNPs could be used as an alternative anti-colitic option due to their strong anti-inflammatory, antioxidant, and anti-apoptotic activities.

Mersaquinone, A New Tetracene Derivative from the Marine-Derived Streptomyces sp. EG1 Exhibiting Activity against Methicillin-Resistant Staphylococcus aureus (MRSA).

New antibiotics are desperately needed to overcome the societal challenges being encountered with methicillin-resistant Staphylococcus aureus (MRSA). In this study, a new tetracene derivative, named Mersaquinone (1), and the known Tetracenomycin D (2), Resistoflavin (3) and Resistomycin (4) have been isolated from the organic extract of the marine Streptomyces sp. EG1. The strain was isolated from a sediment sample collected from the North Coast of the Mediterranean Sea of Egypt. The chemical structure of Mersaquinone (1) was assigned based upon data from a diversity of spectroscopic techniques including HRESIMS, IR, 1D and 2D NMR measurements. Mersaquinone (1) showed antibacterial activity against methicillin-resistant Staphylococcus aureus with a minimum inhibitory concentration of 3.36 µg/mL.

Histopathological Studies on Rabbits Infected by Bacteria Causing Infectious Keratitis in Human through Eye Inoculation.

AIM: This study aimed to investigate the pathogenic effect of bacteria causing infectious keratitis among patients through experimental study conducted on rabbits' eyes with the aid of histopathology as eye infection is a common disease in developing countries that may complicate to loss of vision. METHODOLOGY: 100 swab samples were collected from human infected eyes, at Qassim region during 2012, for the isolation of Pseudomonas aeruginosa and Staphylococcus aureus. The isolated pathogenic bacteria were tested to various antibiotics using some selected antibiotics discs through agar-well diffusion method. Then, experimental study conducted on 27 rabbits. The rabbits were divided randomly into three equal groups, each containing 9 rabbits. Rabbits of group (1) served as control group (Negative Control) and their eyes were inoculated with the buffer only. Rabbits of group (2) were inoculated through eyes with the isolated Pseudomonas aeruginosa. Rabbits of group (3) were inoculated through eyes with the isolated Staphylococcus aureus. RESULTS: Out of 100 collected swab samples from human infected eyes, Pseudomonas aeruginosa and Staphylococcus aureus were isolated with a total percentage of 25.21% and 15.65%; respectively and used in this study. Both bacterial isolates were sensitive to Gentamicin and Cefuroxime. Clinically, experimentally infected rabbits by Pseudomonas aeruginosa, revealed varying degree corneal abrasions, corneal abscess and dense corneal opacity. Histopathologically, at 3(rd) day post-infection (PI), the cornea revealed polymorpho-nuclear cells infiltration with loss of the outer epithelial lining. At 7(th) day PI, neutrophils were seen in the stroma. At 15(th) day PI, proliferation of fibroblasts and new vascularisation were seen in the stroma. Clinically, rabbits experimentally infected with Staphylococcus aureus, revealed corneal ulcers and focal abscesses. Histopathologically, at 3(rd) and 7(th) day PI, the cornea revealed edema and infiltration of leukocytes. At 15(th) day PI, hyperplasia of corneal epithelium and proliferation of keratocytes were evident. The liver and kidneys of experimented rabbits revealed no remarkable histopathological alterations along the period of experiment. CONCLUSION: Pseudomonas aeruginosa and Staphylococcus aureus are common eye infection in human, both induced severe lesions in the eyes of rabbits that could interfere with vision, therefore, strict measures to control these infections in human is recommended.