Comparative in vitro activity of selected antibacterial agents against Escherichia coli isolated from hospitalized patients suffering UTI

Escherichia coli is the most studied among those bacteria causing urinary tract infections. This study was aimed to find out antibacterial activity and minimum inhibitory concentration of selected antibacterial agents against E. coli isolates of hospitalized UTI patients. The specimens were inoculated on Eosin Methylene Blue medium. E. coli isolates were identified via colonial morphology, biochemical testing and API-20 kit. The susceptibility pattern of antibacterial agents was determined applying disc diffusion method (Kirby-Bauer) and dilution tube method. Among all, 38.82% (n=158/407) specimens were positive for E. coli, while the rest showed either no growth or exhibited colonies other than E. coli. while observing the susceptibility pattern, Imipenem was found the most effective (73.42%) antibacterial agent, followed by nitrofurantoin (52.53%), cefpirome (44.94%) and tazobactam/ piperacillin (44.94%), whereas the E. coli isolates were highly resistant to sulfamethoxazole/trimethoprim (71.52%), followed by Amoxicillin-clavulanic acid (67.72%), nalidixic acid (66.46%) and Tobramycin (62.03%), when tested by disc diffusion method. The isolates were susceptible to cefpirome (39.87%) and tobramycin (39.87%) and resistant to sulfamethoxazole/trimethoprim (75.32%), followed by levofloxacin (61.39%), when tested by tube dilution method. The study concluded high degree of resistance against Sulfamethoxazole/trimethoprim, in contrast, cephalosporin and Imipenem exhibited good potency which can be recommended for UTI.

Differentiation of Brain Tumor Microvasculature From Normal Vessels Using Optical Coherence Angiography

BACKGROUND AND OBJECTIVES

Despite rapid advances and discoveries in medical imaging, monitoring therapeutic efficacy for malignant gliomas and monitoring tumor vasculature remains problematic. The purpose of this study is to utilize optical coherence angiography for vasculature characterization inside and surrounding brain tumors in a murine xenograft brain tumor model. Features included in our analysis include fractional blood volume, vessel tortuosity, diameter, orientation, and directionality.

STUDY DESIGN/MATERIALS AND METHODS

In this study, five tumorous mice models at 4 weeks of age were imaged. Human glioblastoma cells were injected into the brain and allowed to grow for 4 weeks and then imaged using optical coherence tomography.

RESULTS

Results suggest that blood vessels outside the tumor contain a greater fractional blood volume as compared with vessels inside the tumor. Vessels inside the tumor are more tortuous as compared with those outside the tumor. Results indicate that vessels near the tumor margin are directed inward towards the tumor while normal vessels show a more random orientation.

CONCLUSION

Quantification of vascular microenvironments in brain gliomas can provide functional vascular parameters to aid various diagnostic and therapeutic studies. © 2021 Wiley Periodicals LLC.

Multimodal imaging of skin lesions by using methylene blue as cancer biomarker

This study aimed the optical imaging of malignant and normal skin tissues with multimodal wide-field fluorescence polarization imaging (WF) technique, by using methylene blue as fluorescence dye. We present optical imaging of skin tissues by different techniques, including reflectance, fluorescence, and polarization imaging for early detection of skin cancer. We collected the reflectance confocal images at 390 and 500 nm. For wide-field fluorescence images, specimens were stimulated at 640 nm and images were collected between 670 and 710 nm. The correlation of the regarded optical modalities with histopathology (H&E), their potentials, capabilities, and limitations to detect skin lesions are discussed. The advantages of multimodal imaging of skin tissues are analyzed to divulge possibilities for precise tumor boundary detection and their classification for malignant and nonmalignant skin tissues. Prior to imaging, the cells were stained in aqueous MB (a dye approved by FDA).

Hemoglobin structure at higher levels of hemoglobin A1C in type 2 diabetes and associated complications

BACKGROUND

Fourier transform infrared (FTIR) spectroscopy technique has not been used as a diagnostic tool for diabetes in clinical practice. This study was linked to structural changes in hemoglobin (Hb) in type 2 diabetes patients at higher levels of HbA1C using FTIR spectroscopy.

METHODS

Fifty-three diabetic patients from the Bahawal Victoria Hospital, Bahawalpur, Pakistan were categorized as group A (6% < HbA1C < 7%; n = 25) and group B (HbA1C ≥9%; n = 28). Another group (group N) of twenty blood samples was taken from healthy people from the Islamia University Bahawalpur, Pakistan. Data from all groups were collected from January 1, 2018 to March 31, 2019. The structure of Hb was studied by FTIR spectroscopy and impact of glucose on the fine structure of HbA1C was estimated.

RESULTS

Hb secondary structure erythrocyte parameters were altered by changing glucose concentrations. From FTIR spectra of all three groups it was found that Hb structure was slightly altered in group A, but significantly changed in group B (P < 0.05). There was an increase in β-sheet structure and a reduction in α-helix structure at elevated levels of HbA1C (group B) in type 2 diabetes.

CONCLUSION

We suggest that higher level of glycation reflected by increased HbA1C might be a contributing factor to structural changes in Hb in type 2 diabetic patients. FTIR spectroscopy can be a novel technique to find pathogenesis in type 2 diabetes.

Hematological complications under hyper conditions of glucose and distilled water

This work presents a pilot method of hematological diagnosis about changes in: shape, size and rouleaux formation, cell count of leucocytes and platelet cells in the presence of different glucose [C₆H₁₂O₆] and water [H2O] concentrations. The 2D microscopic images after addition of ten different glucose concentrations to normal blood (0 mM- 450 mM) revealed the lyses (disintegration) of white blood cells (WBCs). This work provides a baseline to diagnose blood disorders and complications at labs and clinical environment.

Interpretation of Gamma Index for Quality Assurance of Simultaneously Integrated Boost (SIB) IMRT Plans for Head and Neck Carcinoma

Objective: The Gamma Index is prerequisite to estimate point-by-point difference between measured and calculated dose distribution in terms of both Distance to Agreement (DTA) and Dose Difference (DD). This study aims to inquire what percentage of pixels passing a certain criteria assure a good quality plan and suggest gamma index as efficient mechanism for dose verification of Simultaneous Integrated Boost Intensity Modulated Radiotherapy plans.

Method: In this study, dose was calculated for 14 head and neck patients and IMRT Quality Assurance was performed with portal dosimetry using the Eclipse treatment planning system. Eclipse software has a Gamma analysis function to compare measured and calculated dose distribution. Plans of this study were deemed acceptable when passing rate was 95% using tolerance for Distance to agreement (DTA) as 3mm and Dose Difference (DD) as 5%.

Result and Conclusion: Thirteen cases pass tolerance criteria of 95% set by our institution. Confidence Limit for DD is 9.3% and for gamma criteria our local CL came out to be 2.0% (i.e., 98.0% passing). Lack of correlation was found between DD and γ passing rate with R2 of 0.0509. Our findings underline the importance of gamma analysis method to predict the quality of dose calculation. Passing rate of 95% is achieved in 93% of cases which is adequate level of accuracy for analyzed plans thus assuring the robustness of SIB IMRT treatment technique. This study can be extended to investigate gamma criteria of 5%/3mm for different tumor localities and to explore confidence limit on target volumes of small extent and simple geometry.

Evaluation of dose conformity and coverage of target volume for intensity-modulated radiotherapy of pelvic cancer treatment

BACKGROUND

Better conformity may help in delivering minimum dose to organs at risk (OARs) and maximum dose to planning target volume (PTV). As per the requirements of modern radiotherapy, 95% isodose should cover the PTV, so conformity indices (CIs) are used for evaluating quality of conformation of treatment plans.

AIM

This study aimed to investigate degree of conformity for pelvic patients using intensity-modulated radiotherapy (IMRT) technique. Three formulas of CIs described in literature were analyzed in this study.

SETTINGS AND DESIGN

This study was performed to evaluate degree of conformity of 18 patients treated with radiotherapy treatment plan using cumulative dose volume histogram. Effectiveness of different CIs was explored for IMRT plans using 15 MV photon beam. Doses delivered to OAR were also studied.

STATISTICAL ANALYSIS USED

CI suggested by the International Commission on Radiation Units and Measurements, radiation CI and CI prescription isodose to target volume (PITV) had mean ± standard deviation values of 1.02 ± 0.018, 0.98 ± 0.017, and 1.63 ± 0.333, respectively.

RESULTS AND CONCLUSION

Dose distribution for all patients was highly conformal and clinically acceptable. Values of CI PITV exceeded acceptable value for 27% patients with minor deviation. No statistically significant differences were observed for three CIs reported. Target volume lies between 95% and 107% of prescribed dose which shows ideal target coverage. This simple parameter is advantageous since it is easy to interpret and helped determine quality of treatment plan. This study clearly demonstrated that favorable dose distribution in PTV and OARs is achieved using IMRT technique, and hence, the risk of damage to normal tissues is reduced.