Montreal Chinese Hospital

This study investigates the use of industrial-grade polydimethylsiloxane (PDMS) for mass production of microfluidic chips through Liquid Silicone Rubber Injection Molding (LSR-IM) technologies. Injection molding of PDMS is ubiquitous in the automotive and aerospace industries. Yet, it is not currently applied to large-scale production of microfluidic devices. Here, we manufactured PDMS microfluidics devices using industrial IM systems and measured the values of several physicochemical properties of PDMS important in microfluidics. For the two grades of injection-moldable PDMS studied, properties were found close to those of the standard Sylgard 184 PDMS, except Young’s modulus, which varied from 66% to 250% of the Sylgard 184 value and the absorption of small molecules, which was lower or equal to that within Sylgard 184. Yet, the main benefits of LSR-IM production lie in its systematic process, resulting in an increase in reproducibility of both PDMS surface and bulk properties by decreasing the variance within and between production batches of several variables: Young’s modulus (30-fold), oxygen permeation (10-fold), mean fluorescence intensity of Nile Red (5-fold). Emphasis on biocompatibility of LSR-IM was evaluated by culturing complex and sensitive 3D biology models (tumor spheroids and explants) in injection-molded PDMS devices. We observed no significant differences in cell proliferation relative to samples cultured on conventional Sylgard 184 PDMS devices. Overall, these findings open a direct path from benchtop prototyping to industrialization of PDMS-based microfluidic devices for applications in healthcare.Supplementary InformationThe online version contains supplementary material available at 10.1038/s41598-025-16863-z.

Objectives HLA-B*5701 strongly predicts abacavir hypersensitivity (HSR), but implementation of effective routine screening into clinical practice requires testing be practical and accurate. We tested the proficiency of HLA-B*5701 typing among laboratories using sequence-specific primer PCR. Design and methods DNA panels (1 and 2) were distributed to seven laboratories (A to G) for blinded typing of the HLA-B*5701 allele. Panel 1 ( n=10 samples; n=7 laboratories) included 3 positives and other closely related B17 subtypes (B*5702, B*5703, B*5704 and B*5801). Panel 2 ( n=96 samples; n=4 laboratories) included 36 positives among a broad spectrum of other B alleles. Two laboratories (A and B) also submitted 96 routine samples, typed by the same methodology, to the reference centre for additional analysis by sequence-based typing. Results All laboratories correctly typed panel 1 for HLA-B*5701 carriage. Laboratories A, B and C identified HLA-B*5701 alleles in panel 2 with 100% sensitivity and 100% specificity. Laboratory D reported one false negative, reportedly due to a sampling error. The results obtained for routine samples typed by laboratories A and B and those generated by the reference laboratory using sequencing were fully concordant. Conclusions Detection of HLA-B*5701 alleles among laboratories was 100% specific and 99.4% sensitive, indicating that participating HIV testing laboratories were currently offering effective primary screening to identify individuals at high risk of abacavir HSR. Accurate reporting of HLA-B*5701 status is critical for the safe administration of this drug and participation in quality assurance programmes by all sites who report HLA-B*5701 status should be promoted.

To assess the accuracy and safety of thoracoscopy for the evaluation of pleural disease. Prospective evaluation of patients referred for thoracoscopy. University hospital specializing in chest diseases. We studied 102 patients with pleural disease, the cause of which had not been determined after initial investigation, including thoracentesis and needle biopsy. Eighty-six patients had pleural effusion, 11 had pleural mass, and 5 had pleural effusion in association with a known primary lung carcinoma. All patients had thoracoscopy under local anesthesia with mild sedation. Visually directed biopsies were done of parietal pleura. We recorded clinical characteristics, laboratory data, findings and duration of thoracoscopy, and any complications associated with the procedure. Hospital and clinic follow-up records were reviewed, and patients were contacted by telephone 12 and 24 months after thoracoscopy to assess their health status. One hundred and four thoracoscopies were done in 102 patients. A definitive diagnosis was established in 95 patients: 42 had malignant pleural disease and 53 had benign pleural disease. A diagnosis of benign pleural disease using thoracoscopy could not be confirmed in the remaining 7 patients because of insufficient follow-up information. Overall, thoracoscopy was 96% accurate with a sensitivity of 91%, a specificity of 100% and a negative predictive value of 93% for the diagnosis of pleural malignancy. Thoracoscopy was well tolerated under local anesthesia and entailed hospitalization for less than 24 hours in most cases. No deaths occurred, although 1.9% of patients had major complications, and 5.5% had minor complications. Among patients with pleural disease remaining undiagnosed after usual initial investigation, thoracoscopy done under local anesthesia is a rapid, safe, and well-tolerated procedure with an excellent diagnostic yield that is equivalent to that of thoracotomy.

Four patients with biopsy proven small cell carcinoma of the lung died rapidly following radiotherapy. At autopsy areas of prominent tumor giant cell formation were found at the primary site in all four and in the metastatic sites in three. Giant cell formation in a tumor may be from the development of another tumor, sublethal damage to the original tumor cells or presence of the two components from the outset. The light and electron microscopic appearances of the giant tumor cells and their existence in the nonradiated sites in our cases suggest that small cell carcinoma, as adenocarcinomas and squamous cell carcinomas, may be associated with giant cell carcinoma-like components.

The sera of 200 Chinese adults recently immigrated to Canada from Hong Kong were examined for antibodies to Toxoplasma gondii by the indirect fluorescent antibody technique. It was found that the total incidence was 18.0%. This is significantly lower than that of the indigenous population of the same age groups in this area.