Antitumor activity of α-pinene in T-cell tumors.

T-cell acute leukemia and lymphoma have a poor prognosis. Although new therapeutic agents have been developed, their therapeutic effects are suboptimal. α-Pinene, a monoterpene compound, has an antitumor effect on solid tumors; however, few comprehensive investigations have been conducted on its impact on hematologic malignancies. This report provides a comprehensive analysis of the potential benefits of using α-pinene as an antitumor agent for the treatment of T-cell tumors. We found that α-pinene inhibited the proliferation of hematologic malignancies, especially in T-cell tumor cell lines EL-4 and Molt-4, induced mitochondrial dysfunction and reactive oxygen species accumulation, and inhibited NF-κB p65 translocation into the nucleus, leading to robust apoptosis in EL-4 cells. Collectively, these findings suggest that α-pinene has potential as a therapeutic agent for T-cell malignancies, and further investigation is warranted.

Effectiveness of home visit nursing on improving mortality, hospitalization, institutionalization, satisfaction, and quality of life among older people: Umbrella review.

This umbrella review followed the JBI methodology and synthesized systematic reviews of the effectiveness of long-term home visit nursing for older people (≥ 60 years) on improving mortality, hospitalization, institutionalization, patient satisfaction, and quality of life. Eight bibliographic databases were searched, and 10 reviews with 22 distinct relevant trials (n = 10,765 participants) were included. Mortality was the most frequently examined outcome and satisfaction was the least examined (n = nine and one reviews, respectively). Home visit nursing had a favorable effect on reducing the number of admissions to hospital (n = 1,152 participants in two trials vs. 788 participants in three trials) and no effect on other outcomes. The evidence of the effectiveness of long-term home visit nursing for older people is minimal. Future research needs to be based on a theoretical foundation that explains how interventions are expected to work.

The Impact of COVID-19 on Social Isolation in Long-term Care Homes: Perspectives of Policies and Strategies from Six Countries.

Preventing the spread of COVID-19 in long-term care homes is critical for the health of residents who live in these institutions. As a result, broad policies restricting visits to these facilities were put in place internationally. While well meaning, these policies have exacerbated the ongoing social isolation crisis present in long-term care homes prior to the COVID-19 pandemic. This perspective highlights the dominant COVID-19 LTC policies from six countries, and proposes five strategies to address or mitigate social isolation during the COVID-19 pandemic that can also be applied in a post-pandemic world.

G-CSF-induced sympathetic tone provokes fever and primes antimobilizing functions of neutrophils via PGE2.

Granulocyte colony-stimulating factor (G-CSF) is widely used for peripheral blood stem/progenitor mobilization. G-CSF causes low-grade fever that is ameliorated by nonsteroidal anti-inflammatory drugs (NSAIDs), suggesting the activation of arachidonic acid (AA) cascade. How G-CSF regulated this reaction was assessed. G-CSF treatment in mice resulted in fever, which was canceled in prostaglandin E synthase (mPGES-1)-deficient mice. Mobilization efficiency was twice as high in chimeric mice lacking mPGES-1, specifically in hematopoietic cells, suggesting that prostaglandin E2 (PGE2) from hematopoietic cells modulated the bone marrow (BM) microenvironment. Neutrophils from steady-state BM constitutively expressed mPGES-1 and significantly enhanced PGE2 production in vitro by ß-adrenergic stimulation, but not by G-CSF, which was inhibited by an NSAID. Although neutrophils expressed all ß-adrenergic receptors, only ß3-agonist induced this phenomenon. Liquid chromatography-tandem mass spectrometry traced ß-agonist-induced PGE2 synthesis from exogenous deuterium-labeled AA. Spontaneous PGE2 production was highly efficient in Gr-1high neutrophils among BM cells from G-CSF-treated mice. In addition to these in vitro data, the in vivo depletion of Gr-1high neutrophils disrupted G-CSF-induced fever. Furthermore, sympathetic denervation eliminated both neutrophil priming for PGE2 production and fever during G-CSF treatment. Thus, sympathetic tone-primed BM neutrophils were identified as one of the major PGE2 producers. PGE2 upregulated osteopontin, specifically in preosteoblasts, to retain progenitors in the BM via EP4 receptor. Thus, the sympathetic nervous system regulated neutrophils as an indispensable PGE2 source to modulate BM microenvironment and body temperature. This study provided a novel mechanistic insight into the communication of the nervous system, BM niche components, and hematopoietic cells.

Needs of persons with dementia and their family caregivers in dementia cafés.

BACKGROUND AND AIMS: Several studies have shown the effectiveness and diversity of dementia cafés, whereas there are few published articles in academic research focusing on what persons with dementia and their family caregivers need and whether the services provided satisfy their needs. This study aimed to identify the needs of persons with dementia and their family caregivers participating in dementia cafés in Japan. METHODS: Interviews and participant observations were conducted in nine dementia cafés. Study participants were persons with dementia, their caregivers, and the staff in dementia cafés. Data were analysed using qualitative content analysis. RESULTS AND DISCUSSION: A total of 24 participants were recruited. Needs for persons with dementia were subdivided into five categories: to express their feelings about their current condition; to be accommodated through consideration of their physical and cognitive status; for changes in their health conditions to be noticed; to enjoy entertainment; and to keep in touch with others inside and outside of the dementia café. Needs for family caregivers were subdivided into four subcategories: to express their feelings such as anxiety and guilt and complaints regarding caregiving; to consult about difficulties in daily life; to listen to other family caregivers' experiences; and to keep in touch with others inside and outside of the dementia café. The needs of persons with dementia and family caregivers differ partly. CONCLUSIONS: Dementia cafés should create programmes and comfortable environments answering to the differences of their needs.

Validation of family conflict scales for family caregivers of persons with dementia in long-term care facilities and exploration of family conflicts and support.

ABSTRACTBackground:The aim of the study was to develop a family conflict scale for family caregivers of persons with dementia in long-term care facilities and to explore the relationship between family conflicts and family support. METHODS: The scale was developed through forward- and back-translations, interviews with 12 staff members in long-term care facilities, and cognitive interviews with 12 family caregivers who met operational definitions in this study. The test was conducted with 334 family caregivers and a retest was conducted with 318 family caregivers who had indicated willingness to participate further. RESULTS: The internal consistency was relatively high for all subscales (Cronbach's α >0.87); sufficient retest reliability was demonstrated for all subscales (intraclass correlation coefficient >0.69). Confirmatory factor analysis supported a three-factor model. Convergent and discriminant validity for each of the family conflict scale subscales, family APGAR, and the Symptom Check List-90 Items-Revised were acceptable. Family caregivers who received no family assistance for caregiving perceived more conflict in their family than those receiving family assistance. CONCLUSIONS: The Japanese version of the family conflict scale for family caregivers of persons with dementia in long-term care facilities was developed. The reliability and validity of the scale were verified. When providing support to family caregivers in long-term care facilities, it is necessary to consider the family from multiple viewpoints, including family conflicts and support conditions from other family members.

Evaluation of Pigment Distribution and Depth Analysis Methods for Decorative Soft Contact Lenses.

OBJECTIVES: This study evaluates pigment component distribution and depth in decorative soft contact lenses (DSCLs) using a variety of analytical methods. METHODS: We sampled 18 DSCLs using optical microscopy, optical coherence tomography analysis, Z-stack analysis, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM/EDX), and time-of-flight secondary ion mass spectrometry (TOF-SIMS) to evaluate the distribution and depth of pigment components. RESULTS: Pigment distribution in DSCLs was easily observed with optical methods including Z-stack analysis. X-ray photoelectron spectroscopy, SEM/EDX, and TOF-SIMS were used to evaluate the level of pigment exposure on the lens surface and the results showed significant differences between the methods. Pigment components were detected in 16 samples by SEM/EDX, but not by XPS. Pigment components were only detected in eight samples using TOF-SIMS. CONCLUSIONS: It may be necessary to show that a nanometer-thick monomolecular film does not exist on the surface of DSCLs, to demonstrate the exposure of a pigment particle. Taking into account the principle behind each of the measurement methods and the resolution and sensitivity of each of the analytical methods compared, TOF-SIMS may be the most appropriate method to accurately judge pigment exposure on DSCLs. The Z-stack method may be useful for estimating the depth of pigment components in DSCLs.

A Mutation in the 16S rRNA Decoding Region Attenuates the Virulence of Mycobacterium tuberculosis.

Mycobacterium tuberculosis contains a single rRNA operon that encodes targets for antituberculosis agents, including kanamycin. To date, only four mutations in the kanamycin binding sites of 16S rRNA have been reported in kanamycin-resistant clinical isolates. We hypothesized that another mutation(s) in the region may dramatically decrease M. tuberculosis viability and virulence. Here, we describe an rRNA mutation, U1406A, which was generated in vitro and confers resistance to kanamycin while highly attenuating M. tuberculosis virulence. The mutant showed decreased expression of 20% (n = 361) of mycobacterial proteins, including central metabolic enzymes, mycolic acid biosynthesis enzymes, and virulence factors such as antigen 85 complexes and ESAT-6. The mutation also induced three proteins, including KsgA (Rv1010; 16S rRNA adenine dimethyltransferase), which closely bind to the U1406A mutation site on the ribosome; these proteins were associated with ribosome maturation and translation initiation processes. The mutant showed an increase in 17S rRNA (precursor 16S rRNA) and a decrease in the ratio of 30S subunits to the 70S ribosomes, suggesting that the U1406A mutation in 16S rRNA attenuated M. tuberculosis virulence by affecting these processes.

Posttranscriptional modulation of cytokine production in T cells for the regulation of excessive inflammation by TFL.

Posttranscriptional machinery regulates inflammation and is associated with autoimmunity as well as tumorigenesis in collaboration with transcription factors. We previously identified the tumor suppressor gene transformed follicular lymphoma (TFL) on 6q25 in a patient with follicular lymphoma, which transformed into diffuse large B cell lymphoma. TFL families have a common RNase domain that governs macrophage-mediated inflammation. In human peripheral blood, TFL is dominantly expressed at the glycine- and tryptophan-rich cytoplasmic processing bodies of T lymphocytes, and it is persistently upregulated in activated T cells. To address its physiological role, we established TFL(-/-) mice in which TFL(-/-) lymphocytes proliferated more rapidly than TFL(+/+) upon stimulation with inappropriate cytokine secretion, including IL-2, IL-6, and IL-10. Moreover, TFL inhibited the synthesis of cytokines such as IL-2, IL-6, IL-10, TNF-α, and IL-17a by 3' untranslated region RNA degradation. Experimental autoimmune encephalitis induced in TFL(-/-) mice demonstrated persistent severe paralysis. CNS-infiltrated CD4(+) T cells in TFL(-/-) mice contained a higher proportion of Th17 cells than did those in TFL(+/+) mice during the resolution phase, and IL-17a mRNA levels were markedly increased in TFL(-/-) cells. These results suggest that TFL may play an important role in attenuating local inflammation by suppressing the infiltration of Th17 cells in the CNS during the resolution phase of experimental autoimmune encephalitis. TFL is a novel gradual and persistent posttranscriptional regulator, and the TFL-driven attenuation of excessive inflammation could contribute to recovery from T cell-mediated autoimmune diseases.

Proof of concept testing of a positive reference material for in vivo and in vitro sensitization testing of medical devices.

In vivo skin sensitization tests are required to evaluate the biological safety of medical devices in contact with living organisms to provide safe medical care to patients. Negative and positive reference materials have been developed for biological tests of cytotoxicity, implantation, hemolysis, and in vitro skin irritation. However, skin sensitization tests are lacking. In this study, polyurethane sheets containing 1 wt/wt % 2,4-dinitrochlorobenzene (DNCB-PU) were developed and evaluated as a positive reference material for skin sensitization tests. DNCB-PU sheet extracts prepared with sesame oil elicited positive sensitization responses for in vivo sensitization potential in the guinea pig maximization test and the local lymph node assay. Furthermore, DNCB-PU sheet extracts prepared with water and acetonitrile, 10% fetal bovine serum-containing medium, or sesame oil elicited positive sensitization responses as alternatives to animal testing based on the amino acid derivative reactivity assay, human cell line activation test, and epidermal sensitization assay, respectively. These data suggest that the DNCB-PU sheet is an effective extractable positive reference material for in vivo and in vitro skin sensitization testing in medical devices. The formulation of this reference material will lead to the development of safer medical devices that contribute to patient safety.

[Comprehensive analyses of hydrolyzed wheat protein using shotgun proteomics].

Hydrolyzed wheat protein (HWP; hydrolyzed gluten) is used in various types of products worldwide. Several cases of wheat-dependent, exercise-induced anaphylaxis following exposure to HWP (Glupearl 19S) in cosmetics have been reported. Glupearl 19S was produced from the gluten after partial hydrolysis with hydrogen chloride, and its allergenicity is larger than that of gluten (Adachi R., Allergy 2012;67:1392-9.). It is considered that provocation of allergic manifestations is caused by deamidated gluten in food and/or non-food products. Moreover, an increasing number of studies have shown that HWP can induce IgE-mediated hypersensitivity by skin contact and/or food ingestion. However, the essential molecular properties and profiles of HWP are still unknown. In this study, bioinformatic and multivariate analyses using shotgun proteomics have revealed that 27 proteins significantly decreased in Glupearl 19S compared with intact gluten as shown by the ratio of ion signal intensity of tryptic peptides. In contrast, a single protein significantly increased in HWP compared with intact gluten as shown by the ratio of ion signal intensity of tryptic peptides. Furthermore, we have identified six Glupearl 19S-specific peptides using shotgun proteomics, database searches on Mascot Sequence Query, and de novo sequencing. The six peptides were identified as the specific markers of Glupearl 19S.

Tfl deletion induces extraordinary Cxcl13 secretion and cachexia in VavP-Bcl2 transgenic mice.

STATEMENT OF SIGNIFICANCE: Loss of TFL, found in several types of lymphoma, induces excessive CXCL13 secretion through RNA dysregulation contributing to body weight loss and early death in lymphoma model mice. Follicular lymphoma (FL) is associated with overexpressed BCL-2 and other genetic aberrations, including 6q-. We identified a novel gene on 6q25, "Transformed follicular lymphoma (TFL)," from a transformed FL. TFL regulates several cytokines via mRNA degradation, which has been suggested to underlie resolving inflammation. Fluorescence in situ hybridization revealed a deletion of TFL occurred in 13.6% of various B-cell lymphoma samples. We developed VavP-bcl2 transgenic, TFL deficit mice (Bcl2-Tg/Tfl -/-) to seek how TFL affects disease progression in this lymphoma model. While Bcl2-Tg mice developed lymphadenopathy and died around 50 weeks, Bcl2-Tg/Tfl -/- mice lost body weight around 30 weeks and died about 20 weeks earlier than Bcl2-Tg mice. Furthermore, we found a unique B220-IgM+ cell population in the bone marrow of Bcl2-Tg mice. cDNA array in this population revealed that Cxcl13 mRNA in Bcl2-Tg/Tfl -/- mice expressed significantly higher than Bcl2-Tg mice. In addition, bone marrow extracellular fluid and serum showed an extremely high Cxcl13 concentration in Bcl2-Tg/Tfl -/- mice. Among bone marrow cells, the B220-IgM+ fraction was the main producer of Cxcl13 in culture. A reporter assay demonstrated TFL regulates CXCL-13 via induction of 3'UTR mRNA degradation in B lineage cells. These data suggest Tfl regulates Cxcl13 in B220-IgM+ cells in the bone marrow, and a very high concentration of serum Cxcl13 arising from these cells may contribute to early death in lymphoma-bearing mice. Since several reports have suggested the association of CXCL13 expression with lymphoma, these findings provide new insights into cytokine regulation via TFL in lymphoma.

Toward developing care outcome quality indicators for home care for older people: A prospective cohort study in Japan.

INTRODUCTION: Care quality in Japan's long-term care (LTC) agencies, including home care, is the responsibility primarily of individual agencies, and the evaluation of service processes and outcomes is minimal. OBJECTIVES: To describe the development of quality indicators for LTC (QIs-LTC) in Japan. METHODS: QIs-LTC were developed through literature review and expert panel discussions and then were piloted and used in a 2-year longitudinal survey. The survey (launched in September 2019) targeted older people receiving home care (n = 1450), their family members (n = 880), their professional home care providers (n = 577), and managers of home care agencies (n = 122). RESULTS: Across eight domains (maintaining dignity, minimizing symptoms and disease deterioration, maintaining nutritional status, maintaining bladder/bowel control, encouraging physical activities, experiencing sound sleep, maintaining serenity and contentedness, and maintaining family's well-being), 24 care quality objectives were set with 24 outcome QIs-LTC and 144 process QIs-LTC. In the survey, 84.8% of clients were using home care nursing, 26.3% were living alone, and 39.5% had dementia. In the month preceding the data collection, 13.9% of clients had a new disease or worsening of an existing disease, 8.8% were hospitalized at least once, and 47.9% did not participate in activities of interest. About 20% of clients' families were unable to spend time peacefully, and 52.8% were exhausted from the client's care. CONCLUSIONS: The QIs-LTC developed in the current study are generic and client- and family-centered. They encompass objective and subjective information and would facilitate standardized monitoring if adopted and comparison between LTC settings, including home care. In addition, future research directives are outlined. Geriatr Gerontol Int 2023; 23: 383-394.

Family-oriented interventions in long-term care residential facilities for older people: A scoping review of the characteristics and outcomes.

INTRODUCTION: Family-oriented interventions in long-term care (LTC) residential facilities are heterogenous in design, characteristics, and outcomes. OBJECTIVES: To synthesize characteristics (e.g., type, provider, and duration) and outcomes of family-oriented interventions in LTC residential facilities. METHODS: We followed the JBI methodology and searched seven databases for quantitative, qualitative, and mixed method studies that reported family-oriented interventions in LTC residential settings for older people; defined in this review as ≥60 years. Interventions that included residents, resident families, health professionals, or any combinations of these three were included if the study reported post-intervention assessment of at least one family-related outcome. RESULTS: Thirteen studies met the inclusion criteria. Interventions were found to be multifaceted, and education was the most common element. Nurses were the most common intervenors, and most interventions had more than one target (residents, resident families, or staff). Most outcomes were related to family involvement, satisfaction with care, quality of life, communication, symptom management, and shared decision making, and none of the studies reported a negative impact. CONCLUSIONS: Family-oriented interventions were associated with high care quality and better resident-staff-family partnership. Staff education and staff-family conversation are relatively cheap interventions to help family involvement, facilitate shared decision-making, and improve family satisfaction.

Performance evaluation of bactericidal effect and endotoxin inactivation by low-temperature ozone/hydrogen peroxide mixed gas exposure.

This study evaluated the performance of a new O3 /H2 O2 mixed gas sterilization instrument for killing microorganisms and inactivating bacterial endotoxin at low temperatures. Sterility assurance level was achieved by an over 6-log reduction of Geobacillus stearothermophilus ATCC 12980, and the decimal reduction value was 0.77 min in sterilization mode. A reduction of over 3 logs in Limulus amebocyte lysate coagulation activity of purified endotoxin from Escherichia coli was observed after treatment in endotoxin-inactivation mode. The same inactivation ability was observed when treating dried bacterial cells. Biomaterials made of polymer or metal did not exhibit cytotoxicity after gas exposure at O3 concentrations below 200 ppm. As the results of human cell-based pyrogen testing, significant amounts of endotoxin that were over the limit for medical devices contacting cerebrospinal fluid (2.15 EU/device) were detected on scissors washed with a washer-disinfector and sterilized with ethylene oxide or autoclaving. In contrast, endotoxin decreased to 0.29 ± 0.05 EU/device after O3 /H2 O2 mixed gas sterilization in endotoxin-inactivation mode. Compared to conventional gas sterilization methods, O3 /H2 O2 mixed gas has high sterilization ability and a strong capacity to inactivate endotoxin. It is expected that this sterilization technology will improve the safety of reusable medical devices and utensils for regenerative medicine.

Family-oriented interventions in long-term care residential settings: a scoping review protocol.

OBJECTIVES: The objective of this review will be to identify the characteristics (eg, type, duration, and provider) of family-oriented interventions in long-term care residential settings. The authors will also identify which outcomes are reported in the literature when implementing family-oriented interventions. INTRODUCTION: An array of family-oriented interventions in long-term care residential settings exist. Given the heterogeneity of current literature, mapping characteristics and intended outcomes of family-oriented interventions is an essential step to inform how best to support families of patients in long-term care residential settings. INCLUSION CRITERIA: This review will consider studies describing family-oriented interventions for families of elderly patients in long-term care residential settings, with no exclusion based on country, gender, or comorbidities. Interventions that address any family-related issue, such as quality of life, psychological burden, and family involvement in patient care, are eligible for inclusion. Studies will be excluded if the patients are cared for at their own homes or institutionalized care is provided on a temporary basis. Quantitative, qualitative, and mixed method study designs will be considered for inclusion. METHODS: A scoping review will be conducted using the JBI methodological approach. Seven databases will be systematically searched: MEDLINE, CINAHL, Scopus, Evidence-Based Medicine Reviews including Cochrane Library, PsycINFO, OpenGrey, and the Grey Literature Report. Citations will be screened against the inclusion criteria by two reviewers independently. Relevant data will be extracted from the included studies, and will be synthesized, summarized, and reported following the Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews. Findings will be published in a peer-reviewed journal.

Minor intron retention drives clonal hematopoietic disorders and diverse cancer predisposition.

Most eukaryotes harbor two distinct pre-mRNA splicing machineries: the major spliceosome, which removes >99% of introns, and the minor spliceosome, which removes rare, evolutionarily conserved introns. Although hypothesized to serve important regulatory functions, physiologic roles of the minor spliceosome are not well understood. For example, the minor spliceosome component ZRSR2 is subject to recurrent, leukemia-associated mutations, yet functional connections among minor introns, hematopoiesis and cancers are unclear. Here, we identify that impaired minor intron excision via ZRSR2 loss enhances hematopoietic stem cell self-renewal. CRISPR screens mimicking nonsense-mediated decay of minor intron-containing mRNA species converged on LZTR1, a regulator of RAS-related GTPases. LZTR1 minor intron retention was also discovered in the RASopathy Noonan syndrome, due to intronic mutations disrupting splicing and diverse solid tumors. These data uncover minor intron recognition as a regulator of hematopoiesis, noncoding mutations within minor introns as potential cancer drivers and links among ZRSR2 mutations, LZTR1 regulation and leukemias.

A biological study establishing the endotoxin limit for osteoblast and adipocyte differentiation of human mesenchymal stem cells.

INTRODUCTION: Multipotent mesenchymal stem cells (MSCs) are widespread in adult organisms and are implicated in tissue maintenance and repair, regulation of hematopoiesis, and immunologic responses. Human (h)MSCs have applications in tissue engineering, cell-based therapy, and medical devices but it is unclear how they respond to unfavorable conditions, such as hypoxia or inflammation after transplantation in vivo. Although endotoxin testing is required for evaluating the quality and safety of transplanted MSCs, no reports on their dose response to endotoxins are available to establish the limits for in vitro MSC culture systems. In the present study, we aimed to accurately quantify the risk of endotoxin contamination in cell culture systems to establish an acceptable endotoxin limit for the differentiation of hMSC osteoblasts and adipocytes. METHODS: Three types of bone marrow-derived hMSCs (hMSC-1: 21-year-old, M/B; hMSC-2: 36-year-old, M/B; hMSC-3: 43-year-old, M/C) and adipose-derived stem cells (ADSCs; StemPro Human) were cultured in osteogenic or adipogenic differentiation media, respectively, from commercial kits, containing various concentrations of endotoxin (0.01-100 ng/ml). The degree of adipocyte and osteoblast differentiation was estimated by fluorescent staining of lipid droplets and hydroxyapatite, respectively. To clarify the molecular mechanism underlying the effect of endotoxin on hMSC differentiation, cellular proteins were extracted from cultured cells and subjected to liquid chromatograph-tandem mass spectrometry shotgun proteomics analysis. RESULTS: Although endotoxin did not effect the adipocyte differentiation of hMSCs, osteoblast differentiation was enhanced by various endotoxin concentrations: over 1 ng/ml, for hMSC-1; 10 ng/ml, for hMSC-2; and 100 ng/ml, for hMSC-3. Proteomic analysis of hMSC-1 cells revealed up-regulation of many proteins related to bone formation. These results suggested that endotoxin enhances the osteoblast differentiation of MSCs depending on the cell type. CONCLUSIONS: Since endotoxins can affect various cellular functions, an endotoxin limit should be established for in vitro MSC cultures. Its no-observed-adverse-effect level was 0.1 ng/ml based on the effect on the hMSC osteoblast differentiation, but it may not necessarily be the limit for ADSCs.

Proof of concept testing of a positive reference material for in vivo and in vitro skin irritation testing.

In vivo and in vitro irritation testing is important for evaluating the biological safety of medical devices. Here, the performance of positive reference materials for skin irritation testing was evaluated. Four reference standards, referred to as Y-series materials, were analyzed: a polyvinyl chloride (PVC) sheet spiked with 0 (Y-1), 1.0 (Y-2), 1.5 (Y-3), or 10 (Y-4) parts of Genapol X-080 per 100 parts of PVC by weight. Y-1, Y-2, and Y-3 did not induce skin irritation responses in an in vitro reconstructed human epidermis (RhE) tissue model, as measured by tissue viability or interleukin-1α release, or in an in vivo intracutaneous response test using rabbits. In contrast, Y-4 extracts prepared with saline or sesame oil at 37°C and 50°C clearly elicited positive irritation responses, including reduced viability (< 50%) and significantly higher interleukin-1α release compared with the solvent alone group, in the RhE tissue model and an intracutaneous response test, where substantial necrosis was observed by histopathology. The positive skin irritation responses induced in vitro under various extraction conditions, as well as those elicited in vivo, indicate that Y-4 is an effective extractable positive control material for in vivo and in vitro skin irritation tests of medical devices. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 2807-2814, 2018.

Alternative plasticizer, 4-cyclohexene-1,2-dicarboxylic acid dinonyl ester, for blood containers with protective effects on red blood cells and improved cold resistance.

Di (2-ethylhexyl) phthalate (DEHP), a typical plasticizer used for polyvinyl chloride (PVC), is eluted from PVC-made blood containers and protects against red blood cell (RBC) hemolysis. However, concerns have arisen regarding the reproductive and developmental risks of DEHP in humans, and the use of alternative plasticizers for medical devices has been recommended worldwide. In this study, we propose that the use of a novel plasticizer, 4-cyclohexene-1,2-dicarboxylic acid dinonyl ester (DL9TH), could help produce more useful and safe blood containers. PVC sheet containing DL9TH and di (2-ethylhexyl) 4-cyclohexene-1,2-dicarboxylate (DOTH) provides comparable or superior protective effects to RBCs relative to PVC sheet containing DEHP or di-isononyl-cyclohexane-1,2-dicarboxylate (DINCH® , an alternative plasticizer that has been used in PVC sheets for blood containers). The total amount of plasticizer eluted from DOTH/DL9TH-PVC sheets is nearly the same as that eluted from DEHP-PVC sheets. In addition, DOTH/DL9TH-PVC has better cold resistance than DEHP- and DINCH® -PVC sheets. In vitro and in vivo tests for biological safety based on International Organization for Standardization guidelines (10993 series) suggest that the DOTH/DL9TH-PVC sheet can be used safely. Subchronic toxicity testing of DL9TH in male rats in accordance with the principles of Organisation for Economic Co-operation and Development Test Guideline 408 showed that DL9TH did not induce adverse effects up to the highest dose level tested (717 mg/kg body weight/day). There were no effects on testicular histopathology and sperm counts, and no indications of endocrine effects: testosterone, thyroid-stimulating hormone, follicle-stimulating hormone, and 17ß-estradiol were unchanged by the treatment, compared with the control group. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 1052-1063, 2018.