Molecular Characterization of Isoniazid and Rifampin Resistance of Mycobacterium tuberculosis Clinical Isolates from Malatya, Turkey

Molecular characterization of drug resistance of Mycobacterium tuberculosis strains of different origins can generate information useful for developing molecular methods that are widely applicable for rapid drug resistance detection. Using DNA sequencing and allele-specific polymerase chain reaction (AS-PCR), we investigated genetic mutations associated with isoniazid (INH) and rifampin (RIF) resistance among 29 drug-resistant clinical isolates of M. tuberculosis collected from Malatya, Turkey, including 19 multi-drug-resistant (MDR) isolates. Point mutations were detected at codons 531, 516, 526, and 513 of the RNA polymerase β- subunit gene (rpoB) in 10 (47.6%), five (23.8%), three (14.3%), and three (14.3%) of the 21 RIF-resistant isolates, respectively. Of the five isolates having mutations in codon 516, three also had mutations at codon 527; one had a concurrent mutation at codon 572. Mutations at codon 315 of the catalase-peroxidase-encoding gene (katG) were found in 17 (63.0%) of the 27 INH-resistant isolates. Interestingly, the katG codon 315 mutation was observed at a much higher frequency in MDR isolates than in INH-mono-resistant isolates (∼79% vs. 25%). This study provided the first molecular characterization of INH and RIF resistance of M. tuberculosis clinical isolates from Eastern Turkey, and extended our knowledge of molecular basis of M. tuberculosis drug resistance.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/63182/1/mdr.2005.11.94.pd

The Advantages and Limitations of Ultrasound Elastography in Diagnosis of Thyroid Carcinoma

Thyroid nodules have high prevalence in the general population. Only minorities of thyroid nodules are malignant; nevertheless, still biopsies are performed in differential diagnosis of malignant and benign thyroid nodules. Conventional ultrasound is widely used in diagnosis and characterization of thyroid nodules. There are several suspicious ultrasound features that predict thyroid cancer, such as solid consistence, marked hypoechogenicity, taller-than-wide shape, irregular or microlobulated or spiculated margins, no peripheral hypoechoic halo, and micro- or macrocalcifications. However, none of these signs have high sensitivity or specificity nor high degree of confidence for diagnosis or exclusion of thyroid carcinoma. Ultrasound elastography, recently developed, promising, noninvasive technique that evaluates tissue stiffness, has become one of the main focuses in thyroid imaging. There are two ultrasound elastography methods: strain ultrasound elastography (also known as real-time elastography or qualitative elastography) and shear wave elastography (quantitative elastography and acoustic radiation force impulse imaging). The purpose of this chapter is to present the principles of thyroid application, advantages, and limitations of both ultrasound elastography techniques

The importance of diffusion apparent diffusion coefficient values in the evaluation of soft tissue sarcomas after treatment

Purpose: In our study, we aimed to show the efficiency of diffusion-weighted images at different b-values and apparent diffusion coefficient (ADC) values in the differentiation of recurrent tumours from post-treatment tissue changes. Material and methods: The conventional and diffusion magnetic resonance images (MRIs) of 42 patients operated for soft tissue sarcomas between June 2012 and March 2015 followed up with MRIs that were evaluated by 2 radiologists retrospectively. Diffusion MRIs were acquired at 4 different b-values (50, 400, 800, 1000 s/mm2). The lesions were classified according to conventional MRI findings as post-treatment changes and recurrent tumours. Results: When the patient group with recurrent tumours was compared with the patient group with postoperative changes the ADC calculations were statistically significantly lower for the recurrent tumours at all b-levels (p < 0.001 for all b-levels). The sensitivity of b-50 values lower than 3.01 × 103 mm²/s in showing recurrent tumours was 100% and the specificity was 77.78%. The sensitivity of b-400 values lower than 2.1 × 103 mm²/s in showing recurrent tumours was 80% and the specificity was 96.3%. The sensitivity of b-800 values lower than 2.26 × 103 mm²/s in showing recurrent tumours was 100% and the specificity was 88.89%. The sensitivity of b-1000 values lower than 2 × 103 mm²/s in showing recurrent tumours was 93.3% and the specificity was 92.5%. Conclusions: The ADC values obtained from diffusion-weighted images have high sensitivity and specificity in differentiating recurring soft tissue sarcomas during monitoring after treatment from postoperative changes

The evaluation of cardiac functions in deep Trendelenburg position during robotic-assisted laparoscopic prostatectomy

ObjectiveThis study aimed to demonstrate the reliability of the cardiac cycle efficiency value through its correlation with longitudinal strain by observing the effect of the deep Trendelenburg position.DesignA prospective, observational study.SettingSingle center.ParticipantsBetween May and September 2022, the hemodynamic parameters of 30 patients who underwent robotic assisted laparoscopic prostatectomy under general anesthesia were prospectively evaluated.Measurements and main resultsAll invasive cardiac monitoring parameters and longitudinal strain achieved transesophageal echocardiography were recorded in pre-deep Trendelenburg position (T3) and 10th minute of deep Trendelenburg position (T4). Delta values were calculated for the cardiac cycle efficiency and longitudinal strain (values at T4 minus values at T3). The estimated power was calculated as 0.99 in accordance with the cardiac cycle efficiency values at T3 and T4 (effect size: 0.85 standard deviations of the mean difference: 0.22, alpha: 0.05). At T4, heart rate, pulse pressure variation, cardiac cycle efficiency, dP/dt and longitudinal strain were significantly lower than those at T3 (p = 0.009, p &lt; 0.001, p &lt; 0.001, and p &lt; 0.001, respectively). There was a positive correlation between the delta-cardiac cycle efficiency and delta-longitudinal strain (R2 = 0.36, p &lt; 0.001).ConclusionAlthough the absence of significant changes in mean arterial pressure and cardiac index after Trendelenburg position suggests that cardiac workload has not changed, changes in cardiac cycle efficiency and longitudinal strain indicate increased cardiac workload due to increased ventriculo-arterial coupling

Diagnostic value of diffusion weighted MRI and ADC in differential diagnosis of cavernous hemangioma of the liver.

Aims: To investigate the use of diffusion weighted magnetic resonance imaging (DWI) and the apparent diffusion coefficient (ADC) values in the diagnosis of hemangioma. Materials and methods: The study population consisted of 72 patients with liver masses larger than 1 cm (72 focal lesions). DWI examination with a b value of 600 s/mm2 was carried out for all patients. After DWI examination, an ADC map was created and ADC values were measured for 72 liver masses and normal liver tissue (control group). The average ADC values of normal liver tissue and focal liver lesions, the \u201ccut-off\u201d ADC values, and the diagnostic sensitivity and specificity of the ADC map in diagnosing hemangioma, benign and malignant lesions were researched. Results: Of the 72 liver masses, 51 were benign and 21 were malignant. Benign lesions comprised 38 hemangiomas and 13 simple cysts. Malignant lesions comprised 9 hepatocellular carcinomas, and 12 metastases. The highest ADC values were measured for cysts (3.782\ub10.53 710-3 mm2/s) and hemangiomas (2.705\ub10.63 710-3 mm2/s). The average ADC value of hemangiomas was significantly higher than malignant lesions and the normal control group (p&lt;0.001). The average ADC value of cysts were significantly higher when compared to hemangiomas and normal control group (p&lt;0.001). To distinguish hemangiomas from malignant liver lesions, the \u201ccut-off\u201d ADC value of 1.800 710-3 mm2/s had a sensitivity of 97.4% and a specificity of 90.9%. To distinguish hemangioma from normal liver parenchyma the \u201ccut-off\u201d value of 1.858 710-3 mm2/s had a sensitivity of 97.4% and a specificity of 95.7%. To distinguish benign liver lesions from malignant liver lesions the \u201ccut-off\u201d value of 1.800 710-3 mm2/s had a sensitivity of 96.1% and a specificity of 90.0%. Conclusion: DWI and quantitative measurement of ADC values can be used in differential diagnosis of benign and malignant liver lesions and also in the diagnosis and differentiation of hemangiomas. When dynamic examination cannot distinguish cases with vascular metastasis and lesions from hemangioma, DWI and ADC values can be useful in the primary diagnosis and differential diagnosis. The technique does not require contrast material, so it can safely be used in patients with renal failure. Keywords

Evaluation of emm gene types, toxin gene profiles and clonal relatedness of group A streptococci

The aim of this study is to evaluate antibiotic susceptibilities, emm gene types, toxin gene profiles and clonal relatedness of group A streptococci (GAS) isolates obtained from patients and carriers. A total of 79 clinical isolates from patients and 60 isolates from carriers were included in the study. Emm typing, toxin gene detection for speA, speB, speC, speG and smeZ genes and pulsed-field gel electrophoresis (PFGE) was performed. Twenty-one distinct emm types were detected; the most common types were emm12, emm89, emm1, emm77, emm4 and emm3. The detection rates of both emm types and the toxingenes didn't differ significantly between patients and carriers. The presence of speA and smeZ was significantly higher in emm1 and speG was significantly lower in emm4 when compared to the other emm types. The rate of clustering obtained with PFGE wasn't significantly different in patients and carriers. As a result, twelve of the 21 emm types detected in this study were covered by the 26-valent vaccine, constituting 77.7% of the emm typeable isolates; however the emm4 type which is one of the most common types in the present study is not among this coverage

Evaluation and Management of Antrochoanal Polyps

Antrochoanal polyps (ACPs) are benign polypoid lesions arising from the maxillary antrum and they extend into the choana. They occur more commonly in children and young adults, and they are almost always unilateral. The etiopathogenesis of ACPs is not clear. Nasal obstruction and nasal drainage are the most common presenting symptoms. The differential diagnosis should include the causes of unilateral nasal obstruction. Nasal endoscopy and computed tomography scans are the main diagnostic techniques, and the treatment of ACPs is always surgical. Functional endoscopic sinus surgery (FESS) and powered instrumentation during FESS for complete removal of ACPs are extremely safe and effective procedures. Physicians should focus on detecting the exact origin and extent of the polyp to prevent recurrence

Detecting imipenem resistance in Acinetobacter baumannii by automated systems (BD Phoenix, Microscan WalkAway, Vitek 2); high error rates with Microscan WalkAway

<p>Abstract</p> <p>Background</p> <p>Increasing reports of carbapenem resistant <it>Acinetobacter baumannii </it>infections are of serious concern. Reliable susceptibility testing results remains a critical issue for the clinical outcome. Automated systems are increasingly used for species identification and susceptibility testing. This study was organized to evaluate the accuracies of three widely used automated susceptibility testing methods for testing the imipenem susceptibilities of <it>A. baumannii </it>isolates, by comparing to the validated test methods.</p> <p>Methods</p> <p>Selected 112 clinical isolates of <it>A. baumanii </it>collected between January 2003 and May 2006 were tested to confirm imipenem susceptibility results. Strains were tested against imipenem by the reference broth microdilution (BMD), disk diffusion (DD), Etest, BD Phoenix, MicroScan WalkAway and Vitek 2 automated systems. Data were analysed by comparing the results from each test method to those produced by the reference BMD test.</p> <p>Results</p> <p>MicroScan performed true identification of all <it>A. baumannii </it>strains while Vitek 2 unidentified one strain, Phoenix unidentified two strains and misidentified two strains. Eighty seven of the strains (78%) were resistant to imipenem by BMD. Etest, Vitek 2 and BD Phoenix produced acceptable error rates when tested against imipenem. Etest showed the best performance with only two minor errors (1.8%). Vitek 2 produced eight minor errors(7.2%). BD Phoenix produced three major errors (2.8%). DD produced two very major errors (1.8%) (slightly higher (0.3%) than the acceptable limit) and three major errors (2.7%). MicroScan showed the worst performance in susceptibility testing with unacceptable error rates; 28 very major (25%) and 50 minor errors (44.6%).</p> <p>Conclusion</p> <p>Reporting errors for <it>A. baumannii </it>against imipenem do exist in susceptibility testing systems. We suggest clinical laboratories using MicroScan system for routine use should consider using a second, independent antimicrobial susceptibility testing method to validate imipenem susceptibility. Etest, whereever available, may be used as an easy method to confirm imipenem susceptibility.</p

Investigation of the effect of binding material and Thiobacillus thiooxidans on the heavy metals mobilization in the mine tailings

The total concentrations of arsenic (As), boron (B), cadmium (Cd), copper (Cu), manganese (Mn), lead (Pb), thallium (Tl) and zinc (Zn) in the mine tailings of an abandoned Pb-Zn mining site and an open boron mining site are investigated in this study. In addition, heavy metals' distributions in chemical binding forms and their mobilities with the presence of binding materials and acidic bacteria are examined. The amounts of sulfur and carbonate in the waste and binding materials are also determined according to the static method, in order to define the acid neutralization potential of the wastes. For mobilization studies, mine tailings are mixed with with leonardite and domestic solid waste compost in different ratios (10/0, 9.5/0.5, 9/1; 8/2). Independent from the binding materials, the mobilization effect of sulfur oxidizing Thiobacillus thiooxidans bacteria has been tested and evaluated. Experiments are conducted using a standard leach test EPA 1310B Extraction Procedure, and correlations between the parameters studied were statistically evaluated using the findings of SPSS 24. Although there is no statistically significant reduction in metals' mobilization with the use of leonardite and waste compost, it has been concluded that different binding agents may have different impacts due to the metal type. As a result, it is understood that metals mobility increases in the presence of Thiobacillus thiooxidans in the environment, and that the heavy metal mobility is directly proportional to the exchangeable and acid soluble fraction, followed by the reducible fraction and the amount of metals bound to the organic fractions