Horizontal and vertical microchamber platforms for evaluation of the paracellular permeability of an epithelial cell monolayer.

Epithelial cells serve as a barrier by tightly adhering to each other and contribute to the homeostasis of living organisms by controlling substance permeation. Therefore, evaluation of the barrier function is important in pharmaceutical development processes. However, the widely used Transwell-based assays require the development of the defect-free epithelial cell monolayer above several tens of mm2, often resulting in low reproducibility and requiring a long incubation time. In addition, the culture surface of cells is far from the bottom of the well plate, making it difficult to observe the cell morphology using an optical microscope. Herein, we propose simple polydimethylsiloxane microfluidic devices for evaluating the barrier function of an epithelial monolayer using a microchamber array. After the formation of the epithelial monolayer over microchambers, the permeation of the marker molecules introduced above resulted in increased fluorescence intensity in microchambers, which was monitored using confocal laser scanning microscopy. We show that using this technique, alteration of the paracellular permeability induced by sodium caprate (C10) and cytochalasin-D, permeation enhancing factors, can be elucidated. Furthermore, by tilting the microchamber device 90 degrees, the vertical cell section and microchambers were imaged in the same focal plane, allowing for live visualization of the passage of fluorescent substances across the cell monolayer. This technique is expected to be useful for investigating the relationship between paracellular permeability and cell morphology, which is unattainable through conventional methods.

Identifying Conditions for Protein Synthesis Inside Giant Vesicles Using Microfluidics toward Standardized Artificial Cell Production.

To expand the range of practical applications of artificial cells, it is important to standardize the production process of giant (cell-sized) vesicles that encapsulate reconstituted biochemical reaction systems. For this purpose, a rapidly developing microfluidics-based giant vesicle generation system is a promising approach, similar to the droplet assay systems that are already widespread in the market. In this study, we examined the composition of the solutions used to generate vesicles encapsulating the in vitro transcription-translation (IVTT) system. We show that tuning of the lipid composition and adding poly(vinyl alcohol) to the outer solution improved the stability of the transition process into the lipid membrane so that protein synthesis proceeded in vesicles. The direct integration of α-hemolysin nanopores synthesized in situ was also demonstrated. These protein-synthesizing monodisperse giant vesicles can be prepared by using a simple microfluidic fabrication/operation with a commercial IVTT system.

Single-cell trapping and retrieval in open microfluidics.

Among various single-cell analysis platforms, hydrodynamic cell trapping systems remain relevant because of their versatility. Among those, deterministic hydrodynamic cell-trapping systems have received significant interest; however, their applications are limited because trapped cells are kept within the closed microchannel, thus prohibiting access to external cell-picking devices. In this study, we develop a hydrodynamic cell-trapping system in an open microfluidics architecture to allow external access to trapped cells. A technique to render only the inside of a polydimethylsiloxane (PDMS) microchannel hydrophilic is developed, which allows the precise confinement of spontaneous capillary flow in the open-type microchannel with a width on the order of several tens of micrometers. Efficient trapping of single beads and single cells is achieved, in which trapped cells can be retrieved via automated robotic pipetting. The present system can facilitate the development of new single-cell analytical systems by bridging between microfluidic devices and macro-scale apparatus used in conventional biology.

Sizing of giant unilamellar vesicles using a metal mesh with a high opening ratio.

Size control of giant unilamellar vesicles (GUVs) has been challenged extensively for realizing quantitative assays within these biomimetic reactors. Although microfluidics-based monodisperse GUV generation methods have shown tremendous progress, they are often difficult and still not available for general users. Meanwhile, the conventional bulk methods, which are more flexible in compositions, only generate polydisperse GUVs with a linear dimension ranging more than two orders of magnitude. Here, we characterized the sizing protocol of GUVs using the metal mesh with a large opening area ratio (>35%). Unlike the conventional track-etched membrane filters with a small opening area ratio (<10%), the present method enabled fast filtration (<10 min) to remove GUVs smaller than the mesh size without delicate flow control. We demonstrated that the combination of extrusion and filtration with selected filters produced GUV populations with fairly narrow size distributions (<30% C.V. in diameter).

Usefulness of cell-penetrating peptides and penetration accelerating sequence for nose-to-brain delivery of glucagon-like peptide-2.

Neuropeptides are expected as therapeutic drug candidates for central nervous system (CNS) disorders. Intracerebroventricular (i.c.v.) administration of glucagon-like peptide-2 (GLP-2) has an antidepressant-like effect not only in depression model mice but also in treatment-resistant depression model mice. However, because i.c.v. administration is very invasive, research is progressing on brain delivery using intranasal administration as a non-invasive method. After intranasal administration of the drug, there are two routes to the brain. That of direct delivery from the paracellular route of olfactory epithelium to the brain via the olfactory bulb has been studied, and that of systemic absorption via the paracellular route of respiratory epithelium has been put to practical use. The high degree of vascularization and permeability of the nasal mucosa enables drug delivery via the paracellular route that leads to systemic delivery. Therefore, suppressing systemic absorption may increase drug delivery to brain, so we focused on the transcellular route. We created a GLP-2 derivative by adding cell-penetrating peptides (CPP) and penetration accelerating sequences (PAS), which are reported to provide efficient intracellular uptake, to GLP-2. However, to deliver GLP-2 by the transcellular route, GLP-2 must not only be taken up into cells but also move out of the cells. We investigated in vitro and in vivo function of PAS-CPP-GLP-2 to enable the translocation of GLP-2 directly from the nose to the brain. Derivatization of PAS-CPP-GLP-2 prevented its degradation. In the evaluation of intracellular dynamics, PAS-CPP-GLP-2 enhanced cellular uptake by macropinocytosis with CPP and promoted escape from endosomal vesicles by PAS. This study also showed that PAS-CPP-GLP-2 can move out of cells. Furthermore, only this PAS-CPP-GLP-2 showed an antidepression-like effect within 20 min of intranasal administration. Intranasal administered PAS-CPP-GLP-2 surprisingly showed the effect at the same dose with i.c.v. administration, but intravenous administered PAS-CPP-GLP-2 did not show the effect. These results suggested that PAS-CPP-GLP-2 can be efficiently delivered from the nose to the CNS and show a pharmacological effect, demonstrating the usefulness of PAS and CPP for nose-to-brain delivery of GLP-2.

Elucidating the Membrane Dynamics and Encapsulation Mechanism of Large DNA Molecules Under Molecular Crowding Conditions Using Giant Unilamellar Vesicles.

The conservation throughout evolution of membrane-bound structures that encapsulate genomic material indicates the existence of a simple, physical mechanism that facilitates the enclosing of long-stranded DNA by lipid bilayers. This study aimed to elucidate such a mechanism by investigating how molecular crowding promotes the spontaneous enveloping of model DNA into lipid bilayer membranes. Using fluorescence microscopy and giant unilamellar vesicles (GUVs) we showed that a 166 kb DNA molecule coencapsulated with a model crowder attaches to the inner membrane of the GUVs as they osmotically deflate and after the DNA-membrane complex buds out. The set of results is consistent with the hypothesis that the depletion volume effect is responsible for the spontaneous encapsulation of DNA in the GUVs. This phenomenon may offer novel insights into the basic mechanisms governing membrane encapsulation of long-stranded nucleic acids found in celluar sytems that are independent of genetic control.

A simple microfluidic device for live-imaging of the vertical section of epithelial cells.

We investigated the capability of simple microfluidic devices with trenches having vertical sidewalls for live-cell fluorescence imaging of adherent cells. An epithelial cell line that forms a two-dimensional (2D) sheet was cultured to adhere to the vertical sidewall so that its vertical section can be imaged directly using ordinal inverted-type laser-scanning microscopy. The material and the structure of the device were characterized. We show that the detailed distribution of intracellular organelles, such as microtubules and mitochondria, and of intercellular apparatus, such as claudin and zonula occludens, can be imaged with high spatio-temporal resolution with a single scan.

11ß-hydroxysteroid dehydrogenase type 1 is associated with antiretroviral therapy-induced increase in low-density lipoprotein cholesterol
.

OBJECTIVE: To investigate the association between 11ß-hydroxysteroid dehydrogenase type 1 (11ß-HSD1) activity and antiretroviral therapy (ART)-induced increase in low-density lipoprotein cholesterol (LDL). MATERIALS AND METHODS: We enrolled 62 patients and used liquid chromatography-tandem mass spectrometry to measure 11ß-HSD1 activity, which was expressed as a ratio of the sum of urinary tetrahydrocortisol and allo-tetrahydrocortisol concentrations to urinary tetrahydrocortisone concentration. Patient data, including baseline laboratory values, were extracted from medical records for logistic regression analyses of factors associated with LDL increase during ART. The cutoff 11ß-HSD1 activity ratio associated with the LDL increase during ART was determined using receiver operator characteristic (ROC) curve analysis. RESULTS: The LDL level increased significantly from 88.8 mg/dL before ART to 106.7 mg/dL during ART (p = 0.04). Additionally, patients with increased LDL tended to have a higher 11ß-HSD1 activity ratio (1.59 vs. 1.21, p = 0.06) and longer duration of ART (13.9 vs. 10.2 months, p = 0.07) than patients with unchanged or decreased LDL. The cutoff 11ß-HSD1 activity ratio was 1.226. Results of the univariate logistic regression analysis suggested that 11ß-HSD1 activity ratio ≥ 1.226 was associated with LDL increase during ART (p = 0.011), with an odds ratio of 8.000. CONCLUSION: This study revealed the possible association between 11ß-HSD1 activity and ART-induced LDL increase. The findings of this study suggest that 11ß-HSD1 could be a useful drug target for the treatment of ART-induced hyperlipidemia.

Reverse Transcription Polymerase Chain Reaction in Giant Unilamellar Vesicles.

We assessed the applicability of giant unilamellar vesicles (GUVs) for RNA detection using in vesicle reverse transcription polymerase chain reaction (RT-PCR). We prepared GUVs that encapsulated one-pot RT-PCR reaction mixture including template RNA, primers, and Taqman probe, using water-in-oil emulsion transfer method. After thermal cycling, we analysed the GUVs that exhibited intense fluorescence signals, which represented the cDNA amplification. The detailed analysis of flow cytometry data demonstrated that rRNA and mRNA in the total RNA can be amplified from 10-100 copies in the GUVs with 5-10 µm diameter, although the fraction of reactable GUV was approximately 60% at most. Moreover, we report that the target RNA, which was directly transferred into the GUV reactors via membrane fusion, can be amplified and detected using in vesicle RT-PCR. These results suggest that the GUVs can be used as biomimetic reactors capable of performing PCR and RT-PCR, which are important in analytical and diagnostic applications with additional functions.

A New Approach for Determining Short-Term, Objective Prognostic Predictive Methods for Terminal Cancer Patients Based on the Change Point of Laboratory Test Values.

BACKGROUND: In terminal phase cancer, predicting a prognosis precisely plays an important role for patients and their families to live meaningful lives. However, there are no established short-term, objective prognostic predictive methods. OBJECTIVE: To develop simple, short-term, objective prognostic predictive methods through detecting a change point for laboratory test values. DESIGN: A retrospective chart review. SETTING/SUBJECTS: Subjects were cancer patients aged ≥16 years and discharged dead from Osaka University Hospital in 2008. MEASUREMENTS: Using different laboratory test values, new prognostic predictive methods were determined based on either six laboratory test values (white blood cell [WBC], platelet [PLT], C-reactive protein, blood urea nitrogen [BUN], aspartate aminotransferase [AST], and lactase dehydrogenase [LDH]): the WPCBAL score, or five test values (WBC, PLT, BUN, AST, and LDH): the WPBAL score. Their utility, including sensitivity and specificity, was compared with that of Glasgow prognostic scores (GPSs). RESULTS: In total, 121 cancer patients were enrolled. WPCBAL and WPBAL scores showed higher sensitivity (0.88 and 0.91 vs. 0.68), specificity (0.79 and 0.70 vs. 0.53), negative predictive value (0.98 and 0.97 vs. 0.76), and a much larger relative risk (16.5 and 14.2 vs. 1.78) as prognostic predictors within two weeks of death than GPS as a prognostic predictor within three weeks of death. CONCLUSION: This is the first study that suggests that the objective prognostic predictive methods, through detecting the change point of laboratory test values, are useful for predicting short-term prognosis. The WPCBAL score and WPBAL score could objectively predict the remaining lifetime within two weeks of mortality.

One-step micromolding of complex 3D microchambers for single-cell analysis.

Herein we examined the extent of replicability of the PDMS microchamber device transferred from the master mold with complex 3D structures fabricated via micro stereolithography. Due to the elastomeric properties of PDMS, the reversely tapered micromold, with the diameter ratio of ∼5 from the largest to the narrowest part, was precisely transferred without breaking. We obtained the mathematical model to estimate the stress exerted on the mold during the demolding process. Finally, we tested the applicability of this unusual microchamber for single-cell trapping and an enzyme assay.

Microchamber device for detection of transporter activity of adherent cells.

We present a method to detect the transporter activity of intact adherent cells using a microchamber device. When adherent cells are seeded onto the poly-di-methyl siloxane substrate having microchambers with openings smaller than the size of a cell, the cells form a confluent layer that covers the microchambers, creating minute, confined spaces. As substances exported across the cell membrane accumulate, transporter activity can be detected by observing the fluorescence intensity increase in the microchamber. We tested the microchamber device with HeLa cells over-expressing MDR1, an ATP-binding cassette transporter, and succeeded in detecting the transport of fluorescence-conjugated paclitaxel, the anti-cancer drug, at the single-cell level.

L-glutamine decreases the severity of mucositis induced by chemoradiotherapy in patients with locally advanced head and neck cancer: a double-blind, randomized, placebo-controlled trial.

The incidence of severe mucositis in the oral cavity, pharynx and larynx is high among patients with head and neck cancer (HNC) receiving chemoradiotherapy (CRT), resulting in significant pain and impairment of quality of life. The present study investigated whether L-glutamine (glutamine) decreases the severity of mucositis in the oral cavity, pharynx and larynx induced by CRT. This double-blind, randomized, placebo-controlled trial included 40 untreated patients with squamous cell carcinoma of the nasopharynx, oropharynx, hypopharynx or larynx. Patients received 66 or 70 Gy of total radiation at the rate of 2 Gy/fraction daily and 5 fractions/week. Cisplatin (20 mg/m2) and docetaxel (10 mg/m2) were intravenously co-administered once a week for 6 weeks. Patients were randomized to orally receive either glutamine (group G) or placebo (group P) at a dose of 10 g 3 times a day throughout the CRT course. Mucositis was assessed using the National Cancer Institute Common Terminology Criteria for Adverse Events version 3.0. The primary end point was mucositis severity. Mucositis developed in all patients. A maximal mucositis grade of G4 was observed in 0 and 25% group G and P patients, respectively, while that of G2 was observed in 10 and 0% group G and P patients, respectively (p=0.023). Glutamine significantly decreased the maximal mucositis grade (group G, 2.9±0.3; group P, 3.3±0.4; p=0.005) and pain score at weeks 4, 5 and 6. Glutamine significantly decreased mucositis severity in the oral cavity, pharynx and larynx induced by CRT in patients with HNC.

[Effect of the administration of zoledronic acid on life expectancy in patients with multiple myeloma with or without renal impairment].

Zoledronic acid(ZA)is believed to exert anticancer effects in patients with multiple myeloma(MM). For patients with impaired renal function, its dosage should be determined according to creatinine clearance(Ccr). However, there is no reported difference in life expectancy improvement between those with and without renal impairment. Therefore, we conducted a retrospective study to investigate this clinical question. Seventy-eight MM patients receiving ZA injections were selected and divided into 2 groups: (1)normal group(n=39), baseline Ccr≥60mL/min, and(2)impaired group(n=39), baseline Ccr<60mL/min. Patients in the normal group received a significantly higher initial dose(p<0.001), were of a younger age(p<0.001), had lower b2-microglobulin(b2-M)levels(p<0.001), and had higher rates of prior hematopoietic stem cell transplantation(p<0.001)than those in the impaired group. We then compared the survival rate between 31 patients in the normal group and 27 patients in the impaired group whose treatment outcome data were available and found no significant difference(p=0.251). Therefore, our results suggest that the survival rate on ZA administration may not differ between MM patients with and without renal impairment.

Polysulfides are possible H2S-derived signaling molecules in rat brain.

Accumulating evidence shows that hydrogen sulfide (H2S) has a variety of physiological functions. H2S is produced from cysteine by 3 sulfurtransferases. H2S, in turn, generates polysulfides, the functions of which are not well understood. H2S induces Ca(2+) influx in astrocytes, a type of glia. However, the receptor that mediates the response has not been identified. Here, we have shown that polysulfides induce Ca(2+) influx by activating transient receptor potential (TRP)A1 channels in rat astrocytes (EC50 91 nM, Hill coefficient value 1.77±0.26) and that the maximum response was induced at 0.5 µM, which is 1/320 of the concentration of H2S required to achieve a response of similar magnitude (160 µM, EC50 116 µM). TRPA1-selective agonists, allyl isothiocyanate and cinnamaldehyde, induced Ca(2+) influx, and responses to polysulfides were suppressed by TRPA1-selective inhibitors, HC-030031 and AP-18, as well as by siRNAs selective to TRPA1. The present study suggests that polysulfides are possible H2S-derived signaling molecules that stimulate TRP channels in the brain.

Can gradual dose titration of ketamine for management of neuropathic pain prevent psychotomimetic effects in patients with advanced cancer?

BACKGROUND: Ketamine is often used to manage neuropathic pain in patients with cancer. However, it occasionally causes psychotomimetic effects such as vivid dreams, nightmares, illusions, hallucinations, and altered body image. OBJECTIVE: To examine whether gradual dose titration of ketamine for management of neuropathic pain prevents psychotomimetic effects in patients with advanced cancer. METHODS: This was a retrospective chart review. We administered ketamine when neuropathic pain in patients with advanced cancer became refractory to opioids and oral adjuvant analgesics. The starting dose of ketamine was 10 mg/d by continuous intravenous infusion. The dose was gradually increased by 10 mg/d every 4 to 6 hours to 50 mg/d or until the pain was relieved. It was subsequently increased by 25 mg/d every 12 to 24 hours until the pain was relieved. RESULTS: For this study, we enrolled 46 patients with advanced cancer. The mean age was 52.2 ± 16.9 years. The mean dose at onset of action and maximum dose of ketamine were 56 ± 58 and 272 ± 214 mg/d, respectively. The mean pain intensity (numerical rating scale) decreased significantly from 7.3 ± 2.0 to 3.5 ± 2.2 after the administration of ketamine (P < .01). The effectiveness was 69.5%. No psychotomimetic effect of less than 300 mg/d was observed during the introduction phase even though psychotropic drugs were not prescribed. Mild sedation was observed in 3 patients (7%) as the only adverse effect during the introduction phase. CONCLUSION: Gradual dose titration of ketamine for management of neuropathic pain can prevent psychotomimetic effects in patients with advanced cancer.

A retrospective chart review of terminal patients with cancer with agitation and their risk factors.

BACKGROUND: Agitated delirium is often observed in terminal patients with cancer. To clarify the risk factors for agitated delirium in terminal patients with cancer, we conducted a retrospective chart review of 126 patients with cancer who died at a university hospital in 2008. METHOD: As a working definition, we define agitated delirium as a score of 2 or more in item 9 of the Memorial Delirium Assessment Scale with diurnal variation. RESULTS: The results were as follows: agitated delirium was observed in 49 (42%) of the 115 patients, and it occurred within the last week before death in 49% of the patients. Univariate analysis revealed older age, male gender, smoking history, lung cancer, diabetes, and high C-reactive protein (CRP) value as major risk factors, while dendritic analysis revealed lung cancer, high CRP value, diabetes, older age, and smoking history as key factors for predicting agitation. CONCLUSION: It is necessary to consider risk factors in order to categorize terminal patients with cancer into high- and low-risk groups and undertake possible counter-measures.

Can milnacipran used for neuropathic pain in patients with advanced cancer cause neuromuscular and somatosensory disorders?

BACKGROUND: Milnacipran is one of the classes of drugs that are serotonin and norepinephrine reuptake inhibitors (SNRIs). It is a promising drug for the treatment of neuropathic pain in patients with advanced cancer. However, we found that neuromuscular and somatosensory disorders occurred when milnacipran was used as an adjuvant analgesic. CASE REPORT: A 66-year-old woman with a history of neuropathic pain was given 15 mg of milnacipran after dinner. The next morning she developed stiffness of the fingers, numbness in the mandible, and the soles of her feet felt swollen. Milnacipran was discontinued and her symptoms disappeared immediately. We managed this case, which was becoming severe, by discontinuing milnacipran on early detection of symptoms. DISCUSSION: This is the first report that demonstrates an adverse reaction of milnacipran when used as an analgesic adjuvant, and not as an antidepressant drug, for neuropathic pain in patients with advanced cancer. The analgesic effect of SNRIs will likely be used in the management of neuropathic pain in the future; however, clinicians should be aware of the early adverse reactions to these agents.

Light-induced deterioration test of carboplatin under clinical settings.

Chemotherapeutic drug dosages are calculated precisely based on the patient's height, body weight, and renal function, etc. To ensure safe and favorable outcomes of treatment, dosing solutions are prepared by appropriate mixing of the drug solutions based on such calculations. The package inserts for many injectable preparations include a warning for storing the product "shielded from light." However, there are no reports of stability assessment of a mixed product against light exposure or the residual amount of active ingredient in the dosing solution during or at the end of treatment. We evaluated the stability of carboplatin from the time of mixing of the dosing solution until the end of drug infusion in a clinical-like setting. With 4-hour exposure to outdoor scattered light, the dosing solution began to show discoloration by 1 hour, becoming dark yellow by 4 hours, with reduction of the percent residual carboplatin to about 23%. To identify the optimal light-shielding shade, the dosing solution was shielded from outdoor scattered light with 1 of 3 protective covers: aluminum foil, yellow plastic shade, and brown plastic shade. The yellow plastic shade prevented any changes of the appearance of the dosing solution during the 4-hour exposure period. The percent residual carboplatin, determined by HPLC, in the dosing solution shielded with a yellow plastic shade was about 85.2% at 2 hours and 78.6% at 4 hours. Thus carboplatin dosing solution should be completely shielded from light until infusion is completed.

Can anti-infective drugs improve the infection-related symptoms of patients with cancer during the terminal stages of their lives?

BACKGROUND: Appropriate use of anti-infective drugs is essential in clinical practice. No evidence-based guidelines or protocols have been published on the appropriate use of anti-infective drugs in patients receiving palliative care as yet. METHODS: The medical records, which included the demographic data of patients, anti-infective drug use, bacteriologic findings, symptoms, and hematologic findings were reviewed retrospectively to determine the potential factors that contribute to symptom improvement of patients in terminal phase. RESULTS: Seventy-one patients (64%) who received anti-infective drugs and had a total of 326 episodes of infection were assessed. Symptom improvement was seen in 33.1%. A total of 22.6% of episodes were started on anti-infective drugs during the last week of life and the symptom improvement in these episodes was 9.2%. Symptom improvement was hardly observed when the anti-infective drug was administered during the last week of life. The association between the decrease in the C-reactive protein (CRP) levels, the decrease of the leukocyte count, reduction of fever, and symptom improvement was determined. The decrease of CRP levels was 42.4%; leukocyte, 56.7%; and reduction of fever was 28.4%. The symptom improvement of individual treatment history was also investigated. The symptom improvement of the group who took positive treatment such as chemotherapy, radiotherapy, surgery, and catheter placement was significantly lower than that of no-treatment group. CONCLUSIONS: Active cancer treatment probably induces the symptoms related to infection and the use of anti-infective drugs. Unnecessary and excessive treatment should be avoided, and the symptoms should be managed with consideration of the patient's state of mind in order to improve the quality of life of terminally ill patients.