METHODS: The gacS and gacA genes were screened in 96 clinical CRAB isolates using PCR assay. Pellicle formation assay was performed in Mueller Hinton medium and Luria Bertani medium using borosilicate glass tubes and polypropylene plastic tubes. The biomass of the pellicle was quantitated using the crystal violet staining assay. The selected isolates were further assessed for their motility using semi-solid agar and monitored in real-time using real-time cell analyser (RTCA).
RESULTS: All 96 clinical CRAB isolates carried the gacS and gacA genes, however, only four isolates (AB21, AB34, AB69 and AB97) displayed the ability of pellicle-formation phenotypically. These four pellicle-forming isolates produced robust pellicles in Mueller Hinton medium with better performance in borosilicate glass tubes in which biomass with OD570 ranging from 1.984 ± 0.383 to 2.272 ± 0.376 was recorded. The decrease in cell index starting from 13 hours obtained from the impedance-based RTCA showed that pellicle-forming isolates had entered the growth stage of pellicle development.
CONCLUSION: These four pellicle-forming clinical CRAB isolates could be potentially more virulent, therefore further investigation is warranted to provide insights into their pathogenic mechanisms.
METHODS: Institutional review board approval was obtained from National Medical Research Register (NMRR ID-21-02052-VIL). We retrospectively reviewed the medical records of patients who underwent TPPBx between August 2020 and April 2022. Records were reviewed for patients' characteristics, prostate volume, prostate-specific antigen (PSA) results, biopsy results and pain tolerability. Data was analyzed to determine PCa and clinically significant prostate cancer (csPCa) detection rate. LA was achieved using perineal skin infiltration and a periprostatic nerve block. The commonly used standard side-firing transrectal ultrasound with its Prostate Biplane Transducer was used as an imaging guide. The principles of the Ginsburg protocol were followed. Pain tolerability was assessed using a visual analog scale.
RESULTS: A total of 55 patients with elevated PSA levels underwent freehand TPPBx under LA. The mean age was 67.3 years, the median PSA was 14.2 ng/mL, and the median PSA density (PSAD) was 0.33 ng/mL/cc. The optimal PSAD cutoff for predicting csPCa was 0.35 ng/mL/cc (area under the curve [AUC], 0.792; sensitivity, 87.5%; specificity, 69.2%). PCa was detected in 24 patients (43.6%), of whom 16 (29.1%) had csPCa. The median pain scores during LA infiltration and biopsy were four and two, respectively, which were significant different (P
METHODS: A 1085-bp fragment of 23S rRNA domain V from samples of 62 treatment-naïve patients with H. pylori infection was amplified by PCR with newly designed primers, followed by sequencing.
RESULTS: Of the 62 cases, 42 patients were treated with clarithromycin-based triple therapy and 20 patients were treated with amoxicillin and proton pump inhibitor only; both therapies showed successful eradication rates of 70-73.8%. Sequencing analysis detected 37 point mutations (6 known and 31 novel) with prevalences ranging from 1.6% (1/62) to 72.6% (45/62). A2147G (aka A2143G) appears to be associated with a low eradication rate [40% (2/5) failure rate and 13.3% (6/45) treatment success rate], supporting its role as a clinically significant point mutation. T2186C (aka T2182C) was found in 71.1% (32/45) and 80% (4/5) of treatment success and failure cases, respectively, suggesting that the mutation is clinically insignificant. The eradication success rate in patients with the novel T2929C mutation was decreased three-fold (6.7%; 3/45) compared with the failure rate (20%; 1/5), suggesting that it may play an important role in clarithromycin resistance, thus warranting further study.
CONCLUSION: This study identified multiple known and novel mutations in 23S rRNA domain V through direct sequencing. Molecular detection of clarithromycin resistance directly on biopsies offers an alternative to conventional susceptibility testing.