ABSTRACT
With the rise in extreme weather due to global warming, coupled with globalization facilitating the spread of infectious diseases, there's a pressing need for portable testing platforms offering simplicity, low cost, and remote transmission, particularly beneficial in resource-limited and non-urban areas. We have developed a portable device using loop-mediated isothermal amplification (LAMP) with spectrometric detection to identify Salmonella Typhimurium DNA. The device utilizes the LinkIt 7697 microcontroller and a microspectrometer to capture and transmit spectral signals in real-time, allowing for improved monitoring and analysis of the reaction progress. We built a hand-held box containing a microspectrometer, thermoelectric cooler, ultraviolet LED, disposable reaction tube, and homemade thermal module, all powered by rechargeable batteries. Additionally, we conducted thorough experiments to ensure temperature accuracy within 1 °C under thermal control, developed a heating module with a LinkIt 7697 IoT development board to heat the DNA mixture to the reaction temperature within 3 min, and integrated foam insulation and a 3D-printed frame to enhance the device's thermal stability. We successfully demonstrated the amplification of Salmonella Typhimurium DNA with an impressive sensitivity of 2.83 × 10-4 ng/µL. A remote webpage interface allows for monitoring the temperature and fluorescence during the LAMP process, improving usability. This portable LAMP device with real-time detection offers a cost-effective solution for detecting Salmonella Typhimurium in food products. Its unique design and capabilities make it a promising tool for ensuring food safety.
ABSTRACT
BACKGROUND: Persistent suspicion of prostate cancer (PCa) due to a rising prostate-specific antigen (PSA) level after repeated negative biopsies is a serious challenge in clinical practice. AIM: To determine the role of Hiraoka's transurethral detachment of the prostate (TUDP) combined with biopsy of the peripheral zone during the same session in patients with repeated negative biopsies in the diagnosis of PCa. METHODS: We retrospectively evaluated the records of 10 patients who were eligible for inclusion in our hospital between December 2012 and August 2017. Patient demographics, a family history of PCa, the number of biopsies, prostate volume, pathological examination, and perioperative PSA level were obtained. RESULTS: Two of 10 patients were pathologically diagnosed with PCa after surgery; the Gleason scores were 4 + 4 and 4 + 3, respectively. Both patients subsequently underwent laparoscopic radical prostatectomy. The median PSA levels preoperatively, and 3 mo and 1 year postoperatively in the other eight patients who were diagnosed with benign prostate hyperplasia after surgery were 19.10 ng/mL, 1.10 ng/mL, and 1.15 ng/mL, respectively. The adjusted P values of the 3-mo and 1-year post-operative PSA level vs pre-operative PSA level were 0.003 and 0.026, respectively. None of the patients had increased PSA levels or PCa detected after a median 35 mo of follow-up. CONCLUSION: TUDP combined with peripheral zone biopsy may improve the detection rate of PCa in patients with repeated negative biopsies. The PSA level declined rapidly in patients who had negative pathological examinations after TUDP, which remained stable 1 year after surgery.
ABSTRACT
A novel lignocellulose material, holocellulose from rice straw via the pretreatment of SO3 micro-thermal explosion, was developed to produce sophorolipids (SLs) with Wickerhamiella domercqiae var. sophorolipid CGMCC 1576. The influence factors of inoculum dose, yeast extract concentration and pH regulators (chemical regents used for adjusting/influencing pH) was investigated and discussed. Results showed that W. domercqiae can grow in the rice straw holocellulose hydrolysate, and acquire relative high SL yield of 53.70 ± 2.61 g/L in shake flask culture. Inoculum dose, yeast extract concentration and pH regulator made obvious influence on fermentation parameters, especially on final broth pH and SLs production. Furthermore, there is a strong negative linear correlation existing between final broth pH and lactonic SL or ratio of lac SL/tot SL. Additionally, comparison between SL production and non-glucose carbon sources, culture methods, microbes in previous reports was carried out. These results will be benefit for acquiring SL mixture with suitable lac SL/tot SL ratio for specific purpose and scope economically.
