Detection of Tox A Gene in Pseudomonas aeruginosa Strains Isolated from Dairy Products Using PCR and Determining the Antibiotic Resistance Pattern

Background and Objectives: Due to the high nutritional value of milk, it has an important role in human nutrition, and on the other hand, it is a suitable medium for the growth of bacteria, such as Pseudomonas aeruginosa. Pseudomonas aeruginosa, is an opportunistic pathogen highly resistant to antibiotics and can cause disease in immunodeficient patients. The purpose of this study was isolation of Pseudomonas aeruginosa from raw milk, detection of tox A gene by PCR, and determining antibiotic resistance, multiple resistance of the isolates, and Identification of ESBL isolates.   Methods: In this cross-sectional study, a total of 360 samples (300 samples of raw milk, 30 samples pasteurized milk, and 30 samples of cream), were collected from animal husbandries and stores in Qom city. Initially, the isolates of Pseudomonas aeruginosa, were confirmed by standard microbiological methods, and then the existence of exotoxin A gene in all isolates was detected by PCR method and the antibiotic resistance of the isolates against 10 antibiotics selected from different antibiotic categories, was investigated according to the CLSI standard. The data were analyzed using t-test.   Results: Out of 360 studied samples, 117 Pseudomonas aeruginosa were isolated, among which 101 strains (86.30%) had tox A gene. In antibiotic resistance testing, the highest resistance was seen against ceftazidime, and it was revealed that there is a significant relationship between the presence of tox A gene and antibiotic resistance in the isolates of Pseudomonas aeruginosa.   Conclusion: Due to high presence of Pseudomonas aeruginosa in raw milk and existence of antibiotic resistance genes in this bacterium, applying appropriate strategies for hygiene control in animal husbandries, is necessary to prevent the spread of bacteria

Intraoperative Assessment of High-Risk Thyroid Nodules Based on Electrical Impedance Measurements: A Feasibility Study

Precise diagnosis of thyroid nodules is challenging due to non-diagnostic/inconclusive results and uncertainties about the malignancy of follicular neoplasms (FNs), even in frozen-section pathology. Therefore, surgical management, especially in Bethesda III and IV categories, may be complicated, and sometimes a second surgery may be required. The Thyroid Nodule Impedance Measurement System (TN-IMS) consists of a metallic patch attached to submental skin and a G20 I.V. cannula inserted into the targeted nodules. Two impedance-based parameters named Z1kHz and impedance phase slope (IPS) in 100 kHz to 500 kHz of the thyroid nodules are recorded and compared with their histopathological results as the gold standard. TN-IMS was intra-surgically applied to 103 human thyroid nodules and normal thyroid tissues. A remarkable consistency between defined co-ranges of Z1kHz/IPS and the histopathological status of specimens was achieved (p < 0.001). Based on these measurements, it was concluded that intraoperative bioelectrical impedance scanning of thyroid nodules would be a helpful complementary approach to detecting high-risk excision-required thyroid nodules