Transfer of Lipophilic Markers from PLGA and Polystyrene Nanoparticles to Caco-2 Monolayers Mimics Particle Uptake

Purpose. The objective of this study was to evaluate nanoparticle uptake by the Caco-2 monolayer model in vitro. Special emphasis was placed on the localization and the quantification of the uptake of fluorescently labeled polystyrene and poly(lactic-co-glycolic acid) (PLGA) nanoparticles. Methods. Intracellular fluorescence was localized by fluorescence and confocal laser scanning microscopy. Particle uptake was quantified either directly, by counting internalized nanoparticles after separation from the Caco-2 monolayers, or indirectly, by extraction of the lipophilic fluorescence marker. In vitro release studies of lipophilic markers from nanoparticles were performed in standard buffer systems and buffer systems supplemented with liposomes. Results. Instead of uptake of polystyrene and PLGA nanoparticles by Caco-2 monolayers an efficient transfer of lipophilic fluorescence markers from nanoparticles into Caco-2 cells with subsequent staining of intracellular lipophilic compartments was observed. Whereas in standard buffer no release of fluorescent marker from polystyrene and PLGA nanoparticles was observed, the release studies using liposome dispersions as receiver revealed an efficient transfer of fluorescent marker into the liposome dispersion. Conclusions. The results suggest that the deceptive particle uptake is caused by a collision-induced process facilitating the transfer of lipophilic fluorescent marker by formation of a complex between the nanoparticles and the biomembranes. Diffusion of the marker within this complex into lipophilic compartments of the cell strongly affects quantitative evaluation of particle uptak

Determination of cell survival after irradiation via clonogenic assay versus multiple MTT Assay - A comparative study

For studying proliferation and determination of survival of cancer cells after irradiation, the multiple MTT assay, based on the reduction of a yellow water soluble tetrazolium salt to a purple water insoluble formazan dye by living cells was modified from a single-point towards a proliferation assay. This assay can be performed with a large number of samples in short time using multi-well-plates, assays can be performed semi-automatically with a microplate reader. Survival, the calculated parameter in this assay, is determined mathematically. Exponential growth in both control and irradiated groups was proven as the underlying basis of the applicability of the multiple MTT assay. The equivalence to a clonogenic survival assay with its disadvantages such as time consumption was proven in two setups including plating of cells before and after irradiation. Three cell lines (A 549, LN 229 and F 98) were included in the experiment to study its principal and general applicability

Resting motor threshold and magnetic field output of the figure-of-8 and the double-cone coil

The use of the double-cone (DC) coil in transcranial magnetic stimulation (TMS) is promoted with the notion that the DC coil enables stimulation of deeper brain areas in contrast to conventional figure-of-8 (Fo8) coils. However, systematic comparisons of these two coil types with respect to the spatial distribution of the magnetic field output and also to the induced activity in superficial and deeper brain areas are limited. Resting motor thresholds of the left and right first dorsal interosseous (FDI) and tibialis anterior (TA) were determined with the DC and the Fo8 coil in 17 healthy subjects. Coils were orientated over the corresponding motor area in an angle of 45 degrees for the hand area with the handle pointing in posterior direction and in medio-lateral direction for the leg area. Physical measurements were done with an automatic gantry table using a Gaussmeter. Resting motor threshold was higher for the leg area in contrast to the hand area and for the Fo8 in contrast to the DC coil. Muscle by coil interaction was also significant providing higher differences between leg and hand area for the Fo8 (about 27%) in contrast to the DC coil (about 15%). Magnetic field strength was higher for the DC coil in contrast to the Fo8 coil. The DC coil produces a higher magnetic field with higher depth of penetration than the figure of eight coil

P187 celiprolol double peak occurrence and gastric motility: Nonlinear mixed effect modeling of bioavailability data obtained in dogs

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/31349/1/0000259.pd

Meeting report: International workshop on implementation of biowaivers based on the biopharmaceutics classification system (BCS)

Even though the pivotal article stating the theoretical basis for a biopharmaceutics drug classification (1) was published almost 20 years ago, the extension of BCS-based biowaiver decisions to drugs belonging to BCS classes other than those showing high solubility and high permeability has not yet reached a consensus among regulators, industrial scientists, and academics. Also, within some jurisdictions, BCS principles have not yet been incorporated into legal frameworks and thus have not been used to allow science- and risk-based regulatory flexibility. This report provides a brief description of the presentations from the International Workshop on Implementation of Biowaivers based on the BCS in Buenos Aires, Argentina, that took place on March 5–6, 2015. The meeting was cosponsored by National University of La Plata, Confederación Farmacéutica Argentina, International Pharmaceutical Federation (FIP), and the American Association of Pharmaceutical Scientists (AAPS). The main objectives of the meeting were to describe the state of the art with respect to in vitro and in silico tools to support waiving in vivo bioequivalence studies and to foster discussion about implementing BCS-based biowaiver decisions to support generic drug registration in South America. Two hundred and fifteen scientists from universities, the pharmaceutical industry, and regulatory authorities took part in this meetingFacultad de Ciencias Exacta

Meeting report: International workshop on implementation of biowaivers based on the biopharmaceutics classification system (BCS)

Even though the pivotal article stating the theoretical basis for a biopharmaceutics drug classification (1) was published almost 20 years ago, the extension of BCS-based biowaiver decisions to drugs belonging to BCS classes other than those showing high solubility and high permeability has not yet reached a consensus among regulators, industrial scientists, and academics. Also, within some jurisdictions, BCS principles have not yet been incorporated into legal frameworks and thus have not been used to allow science- and risk-based regulatory flexibility. This report provides a brief description of the presentations from the International Workshop on Implementation of Biowaivers based on the BCS in Buenos Aires, Argentina, that took place on March 5–6, 2015. The meeting was cosponsored by National University of La Plata, Confederación Farmacéutica Argentina, International Pharmaceutical Federation (FIP), and the American Association of Pharmaceutical Scientists (AAPS). The main objectives of the meeting were to describe the state of the art with respect to in vitro and in silico tools to support waiving in vivo bioequivalence studies and to foster discussion about implementing BCS-based biowaiver decisions to support generic drug registration in South America. Two hundred and fifteen scientists from universities, the pharmaceutical industry, and regulatory authorities took part in this meetingFacultad de Ciencias Exacta

Anti-Suicidal Efficacy of Repetitive Transcranial Magnetic Stimulation in Depressive Patients: A Retrospective Analysis of a Large Sample

Background: Suicide is a major public health problem. About 90% of suicide victims have one or more major psychiatric disorder, with a reported 20-fold increased risk for suicide in patients with affective disorders in comparison with healthy subjects. Repetitive transcranial magnetic stimulation (rTMS) has been established as an effective alternative or adjunctive treatment option for patients with depressive disorders, but little is known about its effects on suicide risk. Objective: For the assessment of the effectiveness of rTMS on suicidal ideation and behaviors, we performed a retrospective analysis of a large sample of patients with depressive disorders, who were treated with rTMS. Methods: We analyzed the records of 711 TMS in- and out-patients with depressive affective disorders in a tertiary referral hospital between 2002 and 2017. Out of these patients we were able to collect Hamilton depression rating scale (HAMD) data of 332 patients (180 females, 152 males; age range 20 to 79 years; mean age 47.3 ± 12.3) for which we analyzed the change of suicidal ideation by using item 3 (suicidality) of HAMD. Results: Out of all 711 patients treated with rTMS for their depression, one patient (0.1%) committed suicide during the TMS treatment. In the statistical analysis of the subsample with 332 patients there was an overall amelioration of depressive symptoms accompanied by a significant decrease in the suicidality item with a medium effect size. Decrease in suicidality was not inferior to changes in other items as indicated by effect sizes. Forty-seven percent of patients showed an amelioration in suicidality, 41.3% of patients did not show a change in their suicidality’s scores, and 11.7% of patients showed an increase in suicidality’s scores from baseline to final rating. Correlation of item 3 (suicidality) and item 7 (drive) demonstrated a significant positive association, revealing improved drive with a parallel decreased suicidality. Conclusion: Based on the proposed data, there is no evidence that rTMS increases the risk for suicide during the course of the treatment. Conversely, rTMS tends to reduce suicidal ideation. Our findings call for further rTMS controlled studies using large sample sizes and specific suicidality assessment measures to obtain more conclusive results

Temporomandibular Joint Disorder Complaints in Tinnitus: Further Hints for a Putative Tinnitus Subtype

OBJECTIVE: Tinnitus is considered to be highly heterogeneous with respect to its etiology, its comorbidities and the response to specific interventions. Subtyping is recommended, but it remains to be determined which criteria are useful, since it has not yet been clearly demonstrated whether and to which extent etiologic factors, comorbid states and interventional response are related to each other and are thus applicable for subtyping tinnitus. Analyzing the Tinnitus Research Initiative Database we differentiated patients according to presence or absence of comorbid temporomandibular joint (TMJ) disorder complaints and compared the two groups with respect to etiologic factors. METHODS: 1204 Tinnitus patients from the Tinnitus Research Initiative (TRI) Database with and without subjective TMJ complaints were compared with respect to demographic, tinnitus and audiological characteristics, questionnaires, and numeric ratings. Data were analysed according to a predefined statistical analysis plan. RESULTS: Tinnitus patients with TMJ complaints (22% of the whole group) were significantly younger, had a lower age at tinnitus onset, and were more frequently female. They could modulate or mask their tinnitus more frequently by somatic maneuvers and by music or sound stimulation. Groups did not significantly differ for tinnitus duration, type of onset (gradual/abrupt), onset related events (whiplash etc.), character (pulsatile or not), hyperacusis, hearing impairment, tinnitus distress, depression, quality of life and subjective ratings (loudness etc.). CONCLUSION: Replicating previous work in tinnitus patients with TMJ complaints, classical risk factors for tinnitus like older age and male gender are less relevant in tinnitus patients with TMJ complaints. By demonstrating group differences for modulation of tinnitus by movements and sounds our data further support the notion that tinnitus with TMJ complaints represents a subgroup of tinnitus with clinical features that are highly relevant for specific therapeutic management