Towards personalized medicine: chemosensitivity assays of patient lung cancer cell spheroids in a perfused microfluidic platform.

Cancer is responsible for millions of deaths worldwide and the variability in disease patterns calls for patient-specific treatment. Therefore, personalized treatment is expected to become a daily routine in prospective clinical tests. In addition to genetic mutation analysis, predictive chemosensitive assays using patient's cells will be carried out as a decision making tool. However, prior to their widespread application in clinics, several challenges linked to the establishment of such assays need to be addressed. To best predict the drug response in a patient, the cellular environment needs to resemble that of the tumor. Furthermore, the formation of homogeneous replicates from a scarce amount of patient's cells is essential to compare the responses under various conditions (compound and concentration). Here, we present a microfluidic device for homogeneous spheroid formation in eight replicates in a perfused microenvironment. Spheroid replicates from either a cell line or primary cells from adenocarcinoma patients were successfully created. To further mimic the tumor microenvironment, spheroid co-culture of primary lung cancer epithelial cells and primary pericytes were tested. A higher chemoresistance in primary co-culture spheroids compared to primary monoculture spheroids was found when both were constantly perfused with cisplatin. This result is thought to be due to the barrier created by the pericytes around the tumor spheroids. Thus, this device can be used for additional chemosensitivity assays (e.g. sequential treatment) of patient material to further approach the personalized oncology field.

Scabies outbreak in an intensive care unit with 1,659 exposed individuals--key factors for controlling the outbreak.

OBJECTIVE: To investigate a large outbreak of scabies in an intensive care unit of a university hospital and an affiliated rehabilitation center, and to establish effective control measures to prevent further transmission. DESIGN: Outbreak investigation. SETTING: The intensive care unit of a 750-bed university hospital and an affiliated 92-bed rehabilitation center. METHODS: All exposed individuals were screened by a senior staff dermatologist. Scabies was diagnosed on the basis of (1) identification of mites by skin scraping, (2) identification of mites by dermoscopy, or (3) clinical examination of patients without history of prior treatment for typical burrows. During a follow-up period of 6 months, the attack rate was calculated as the number of symptomatic individuals divided by the total number of exposed individuals. INTERVENTIONS: All exposed healthcare workers (HCWs) and their household members underwent preemptive treatment. Initially, the most effective registered drug in Switzerland (ie, topical lindane) was prescribed, but this prescription was switched to topical permethrin or systemic ivermectin as a result of the progression of the outbreak. Individuals with any signs or symptoms of scabies underwent dermatological examination. RESULTS: Within 7 months, 19 cases of scabies were diagnosed, 6 in children with a mean age of 3.1 years after exposure to the index patient with HIV and crusted scabies. A total of 1,640 exposed individuals underwent preemptive treatment. The highest attack rate of 26%-32% was observed among HCWs involved in the care of the index patient. A too-restricted definition of individuals at risk, noncompliance with treatment, and the limited effectiveness of lindane likely led to treatment failure, relapse, and reinfestation within families. CONCLUSIONS: Crusted scabies resulted in high attack rates among HCWs and household contacts. Timely institution of hygienic precautions with close monitoring and widespread, simultaneous scabicide treatment of all exposed individuals are essential for control of an outbreak.

Topical bioavailability of triamcinolone acetonide: effect of dose and application frequency.

The application frequency of topical corticosteroids is a recurrently debated topic. Multiple-daily applications are common, although a superior efficacy compared to once-daily application is not unequivocally proven. Only few pharmacokinetic studies investigating application frequency exist. The aim of the study was to investigate the effect of dose (Experiment 1) and application frequency (Experiment 2) on the penetration of triamcinolone acetonide (TACA) into human stratum corneum (SC) in vivo. The experiments were conducted on the forearms of 15 healthy volunteers. In Experiment 1, single TACA doses (300 microg/cm(2) and 100 microg/cm(2)) dissolved in acetone were applied on three sites per arm. In experiment 2, single (1 x 300 microg/cm(2)) and multiple (3 x 100 microg/cm(2)) TACA doses were similarly applied. SC samples were harvested by tape stripping after 0.5, 4 and 24 h (Experiment 1) and after 4, 8 and 24 h (Experiment 2). Corneocytes and TACA were quantified by UV/VIS spectroscopy and HPLC, respectively. TACA amounts penetrated into SC were statistically evaluated by a paired-sample t-test. In Experiment 1, TACA amounts within SC after application of 1 x 300 microg/cm(2) compared to 1 x 100 microg/cm(2) were only significantly different directly after application and similar at 4 and 24 h. In Experiment 2, multiple applications of 3 x 100 microg/cm(2) yielded higher TACA amounts compared to a single application of 1 x 300 microg/cm(2) at 4 and 8 h. At 24 h, no difference was observed. In conclusion, using this simple vehicle, considerable TACA amounts were retained within SC independently of dose and application frequency. A low TACA dose applied once should be preferred to a high dose, which may promote higher systemic exposure.

Persistent apoptosis in HIV-1-infected individuals receiving potent antiretroviral therapy is associated with poor recovery of CD4 T lymphocytes.

CD4 T-cell depletion in HIV-1 infection is partly the result of T-cell apoptosis. Spontaneous apoptosis (SA) and apoptosis markers Fas-associated death-domain-like IL-1 beta converting enzyme (FLICE)-like inhibitory protein (FLIP), Bcl-2, TRAIL (tumor necrosis factor-related apoptosis-inducing ligand), TRAIL receptor 1, and Fas were determined in 55 HIV-1 infected persons treated with highly active antiretroviral therapy (HAART) for 48 months. Despite suppressive HAART, SA remained elevated. Increased SA of peripheral blood mononuclear cells (PBMCs) and CD8 T lymphocytes and increased TRAIL receptor 1 expression strongly predicted a poorer recovery of CD4 T-cell count. HAART did not significantly alter anti-or proapoptotic markers in cultured PBMCs and T lymphocytes. The significant relationship between residual T-lymphocyte apoptosis and CD4 T-cell recovery suggests that persistent apoptosis may impede immune restoration.