Methods: A cross sectional prospective study was conducted at Shaheed Ziaur Rahman Medical College Hospital, Bogura, Bangladesh among clinically suspected urinary tract infection patients from January to December, 2018. Clean-catch midstream or catheter-catch urine samples were subjected to bacteriological culture using chromogenic agar media. Antimicrobial susceptibility testing of the isolates was done by Kirby-Bauer disk diffusion method following Clinical and Laboratory Standards Institute guidelines. Descriptive statistical methods were used for data analysis.

Results: Culture yielded a total of 537 (42.8%) significant bacterial growths including 420 (78.2%) multi drug resistant uropathogens from 1255 urine samples. Escherichia coli was the most common isolate (61.6%) followed by Klebsiella spp. (22.5%), Pseudomonas spp. (7.8%), Staphylococcus aureus (5.4%) and Enterobacter spp. (2.6%) with multi drug resistance frequency of 77.6%, 71.9%, 90.5%, 86.2% and 92.9% respectively. There was female preponderance (M:F; 1:1.97; P=0.007) but insignificant differences between paediatric and adult population (43.65% vs. 42.57%) and also among different age groups. Diabetes, chronic renal failure, fever and supra-pubic pain had significant association as co-morbidities and presentations of urinary tract infections (P<0.05). Multi drug resistance ranged from 3.7 to 88.1% including moderate to high resistance found against commonly used antibiotics like ciprofloxacin, cephalosporin, azithromycin, aztreonam, cotrimoxazole and nalidixic acid (28.6 to 92.9%). Isolates showed 2.4 to 32.2% resistance to nitrofurantoin, amikacin, netilmicin and carbapenems except Pseudomonas spp. (66.7% resistance to nitrofurantoin) and Enterobacter spp. (28.6 to 42.9% resistance to carbapenems).

Methods: A cross sectional microbiological study was conducted at the Department of Microbiology, Rajshahi Medical College, Bangladesh from January to December 2019. Aural swabs were collected aseptically from clinically suspected patients irrespective of age and gender attending the ear, nose and throat outpatient department of Rajshahi Medical College Hospital. Aerobic bacterial culture was done and isolates were identified through standard bacteriological identification scheme. Antimicrobial susceptibility testing of isolates was done by modified Kirby-Bauer disk diffusion method following Clinical and Laboratory Standards Institute guidelines.

Results: Of 96 swabs, culture yielded a total of 73 bacterial isolates from 68(70.8%) culture-positive plates including 63 (65.6%) unimicrobial and 5 (5.2%) polymicrobial (mixed growth of a pair of bacteria) growths. Frequency distribution revealed, 40(55%) gram-negative and 33(45%) gram-positive bacteria with Staphylococcus aureus was the leading isolate (37%) followed by Pseudomonas aeruginosa (31.5%), Escherichia coli (13.7%), coagulase-negative Staphylococcus (8.2%), Klebsiella pneumoniae (5.5%) and Proteus spp. (4.1%). Gram-positive bacteria were found to be highly susceptible (100%) to Linezolid and Vancomycin followed by Imipenem (83 to 96.3%), while moderate to high resistance (44 to 67%) was observed against Ciprofloxacin, Ceftriaxone, Ceftazidime, Amoxicillin/Clavulanate and Clindamycin. For gram-negative bacteria, susceptibility ranged from 67 to 100% to Imipenem, 67 to 96% to Piperacillin/Tazobactam and 67 to 83% to Gentamicin, while moderate to high resistance (50 to 75%) was observed against Ciprofloxacin, Ceftriaxone, Ceftazidime and Amoxicillin/Clavulanate.

METHODS: Developed acoustic-solution-sonication-casting methods were applied to fabricate the new graphene-polymer-dental filler nanocomposites. The structure, morphology, rheological and mechanical properties, and antibacterial of the newly fabricated filling-PMMA/ GO nanocomposites were investigated.

RESULTS: Fourier transform infrared (FTIR) showed a significant interaction between the filling and the additional materials. The X-ray diffraction (XRD) analysis revealed a considerable change in crystalline behavior. Optical microscope (OM) with field emission scanning electron microscopy (FESEM) pictures demonstrated a substantial change in the morphology of the samples with a homogeneous and fine dispersion of the nanomaterials in the filler matrix. Multi-frequency ultrasound mechanical properties measured the ultrasonic velocity, absorption coefficient, compressibility, bulk modulus, and other mechanical properties that notably enhanced after GO contributed up to 325% of the ultrasonic absorption coefficient compared with hybrid/nano-fillers. Rheological properties were measured as viscosity, absorption coefficient, and specific viscosity, which significantly improved after adding PMMA and incorporating GO up to 57% of the viscosity, compared with hybrid/nano-fillers. The inhibition zone of moth bacteria, such as Enterococcus faecalis and E. staph bacteria, improved after the contribution of GO nanosheets up to 46%.