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1.
Heliyon ; 9(3): e13921, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36843958

RESUMEN

Since the COVID-19 pandemic, international higher education and student mobility have faced tremendous pressure and challenges. To address COVID-induced challenges and stress, higher education institutions and host governments undertook responses. This article has humanistically looked into the institutional responses of host universities and governments to international higher education and student mobilities during the COVID-19 pandemic. Informed by a systematic literature review of publications released between 2020 and 2021 in a wide range of academic sources, we argue that many of these responses were problematic and did not adequately maintain student well-being and fairness; instead, international students were treated to some extent with poor services in the host countries. To situate our comprehensive overview and propose ideas for forward-thinking conceptualisation, policy, and practice in higher education in the context of the ongoing pandemic, we engage with the literature on ethical and humanistic internationalisation of higher education and (international) student mobilities.

2.
Toxicol Rep ; 9: 1099-1113, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36518375

RESUMEN

The subchronic toxicity of oral L-tryptophan produced by fermentation with metabolically engineered Corynebacterium glutamicum was evaluated in Sprague-Dawley rats. Doses of 0, 500, 1000, and 2000 mg/kg/day were administered to groups of 10 male and 10 female rats for 90 days. For the groups administered 0 and 2000 mg/kg/day, an additional 5 male and 5 female rats were tested as a recovery group. No adverse effects associated with the test substance were observed in all rats during the 90-day administration of the product, irrespective of dose, and at 4 weeks of recovery at dosages of 0 and 2000 mg/kg/day. Furthermore, histochemical and immunohistochemical analyses for L-tryptophan-associated eosinophilia-myalgia syndrome (EMS) did not reveal significant changes in both sexes of groups administered 0 or 2000 mg/kg/day. Based on these results, it could be concluded that there were no significant adverse effects related to the test substance in all animals; therefore, dried L-tryptophan fermentation product can be used as feed additive material.

3.
Toxicol Rep ; 9: 834-841, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36518413

RESUMEN

Steady-calcium formula (SCF), a functional food mixture with potential of joint care, contains five major ingredients. However, the uncertain cross-reactivity among these included ingredients cannot be excluded. Hence, it is important to ensure the safety of this mixture. In this study, the safety of SCF was evaluated through in vitro genotoxicity assessment and 28-day oral toxicity study in rats. The bacterial reverse mutation test and mammalian chromosome aberration test displayed that SCF did not induce mutagenicity and clastogenicity. The 28-day repeated dose assessment of SCF in rats revealed no mortality and adverse effects in clinical signs, body weight, urinalysis, hematology, organ weight, and histopathology at all treated groups. Although some significant changes were observed in food intake and parameters of serum biochemistry at the highest dose in males, they were not dose-related and considered to be within normal range. These findings indicate that SCF does not possess genotoxic potential and no obvious evidence of subacute toxicity. These results demonstrate for the first time that the genotoxicity and subacute toxicity for SCF are negative under our experimental conditions and the no observed adverse effect level (NOAEL) of SCF may be defined as at least 5470 mg/kg/day.

4.
Toxicol Rep ; 8: 747-752, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33854951

RESUMEN

A novel functional drink with nutraceutical properties was formulated from the aqueous extracts of Ilex guayusa, and Vernonanthura patens leaves, and cocoa husks. This juice contains various bioactive compounds, such as phenolic compounds and methylxanthines, with antioxidant and stimulant properties of pharmacological interest. However, it is known whether herbal extracts' interaction may have adverse toxic effects on human health. To evaluate this functional drink's innocuity, we estimated the acute oral toxicity (AOT) in experimental mice. This paper presents the AOT evaluation of two formulations of a functional drink (pre-formulation and microencapsulation) at a single dose of 2000 mg/kg of body weight (b.w.). No signs of adverse toxicity and mortality were observed after a single oral dose of 2000 mg/kg b.w. Likewise, no significant body and organ weight changes, food and water consumption behavior, and no histopathological changes were observed in the main organs evaluated. In conclusion, this functional drink can be categorized as low toxicity " according to the Globally Harmonized Classification System (GHS), making it a potential beverage with high nutritional and pharmacological value.

5.
SSM Popul Health ; 12: 100682, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33134476

RESUMEN

OBJECTIVES: Although cardiovascular disease (CVD) risk has lessened in Korea, it is unclear whether older adults in all socioeconomic strata have benefited equally. This study explored trends in income disparities in CVD risk among older adults in Korea. METHODS: This was a secondary analysis of Korean National Health and Nutrition Examination Survey data (2008-2017), targeting 14,836 older adults (≥65 years). Socioeconomic position, defined as income and use of welfare benefits, was the primary indicator. The outcome was binary for predicted CVD risk (<90th vs. ≥ 90th). The Slope Index of Inequality (SII) and Relative Index of Inequality (RII) were used to assess trends in disparities. RESULTS: The percentage of older adults with a predicted CVD risk of 90% or more declined over time, but this was due to a decrease among the more affluent. Disparities have persisted since 2012, with a worsening trend seen for Medicaid recipients. We found significant absolute and relative disparities among men over 75 years of age in recent years (SII > 0.19, RII > 7). CONCLUSIONS: These results may inform and improve policies regarding income disparity reduction and cardiovascular health.

6.
Toxicol Rep ; 5: 213-219, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29854591

RESUMEN

The 28-day repeated inhalation study was applied for hazard assessment of 3-methoxybutyl chloroformate (3-MBCF) in Sprague Dawley rats. Groups of five rats per sex were exposed 6 h/day, 5 days per week for 4 weeks to test substance concentration (ranging from 3 to 12 ppm) using a whole-body exposure system. At the terminal sacrifice, following blood collection and gross pathological examination, organ weights were determined and fixed organs were examined. The micronucleus test was performed using bone marrow cells. Exposure of 3-MBCF induced mortality at concentrations above 6 ppm. Decreases in body weight and food intake, hematologic alterations, organ weight changes, and gross and microscopic findings were seen even at the lowest concentrations of 3 ppm. Histopathology revealed principal test substance exposure correlated with lesions in the respiratory tract in both male and female rats above 3 ppm. Groups of male rats exposed above 6 ppm show microscopic lesions in spleens, livers, testes and epididymides; however, the micronucleated polychromatic erythrocytes frequency in bone marrow cells was not changed. Based on histopathology of the respiratory tract and other organs, the no observed adverse effect level (NOAEL) of 3-MBCF in the present study was less than 3 ppm.

7.
Toxicol Rep ; 4: 554-559, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29090120

RESUMEN

Magnesium stearate is widely used in the production of dietary supplement and pharmaceutical tablets, capsules and powders as well as many food products, including a variety of confectionery, spices and baking ingredients. Although considered to have a safe toxicity profile, there is no available information regarding its potential to induce genetic toxicity. To aid safety assessment efforts, magnesium sulfate was evaluated in a battery of tests including a bacterial reverse mutation assay, an in vitro chromosome aberration assay, and an in vivo erythrocyte micronucleus assay. Magnesium stearate did not produce a positive response in any of the five bacterial strains tested, in the absence or presence of metabolic activation. Similarly, exposure to magnesium stearate did not lead to chromosomal aberrations in CHL/IU Chinese hamster lung fibroblasts, with or without metabolic activation, or induce micronuclei in the bone marrow of male CD-1 mice. These studies have been used by the Japanese government and the Joint FAO/WHO Expert Committee on Food Additives in their respective safety assessments of magnesium stearate. These data indicate a lack of genotoxic risk posed by magnesium stearate consumed at current estimated dietary exposures. However, health effects of cumulative exposure to magnesium via multiple sources present in food additives may be of concern and warrant further evaluation.

8.
Toxicol Rep ; 4: 507-520, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28959681

RESUMEN

A toxicological evaluation of N-(1-((4-amino-2,2-dioxido-1H-benzo[c][1,2,6]thiadiazin-5-yl)oxy)-2-methylpropan-2-yl)-2,6-dimethylisonicotinamide (S2218; CAS 1622458-34-7), a flavour with modifying properties, was completed for the purpose of assessing its safety for use in food and beverage applications. S2218 exhibited minimal oxidative metabolism in vitro, and in rat pharmacokinetic studies, the compound was poorly orally bioavailable and rapidly eliminated. S2218 was not found to be mutagenic in an in vitro bacterial reverse mutation assay, and was found to be neither clastogenic nor aneugenic in an in vitro mammalian cell micronucleus assay. In subchronic oral toxicity studies in male and female rats, the NOAEL was 140 mg/kg bw/day (highest dose tested) for S2218 sulfate salt (S8069) when administered as a food ad-mix for 13 consecutive weeks. Furthermore, S2218 sulfate salt demonstrated a lack of maternal toxicity, as well as adverse effects on fetal morphology at the highest dose tested, providing a NOAEL of 1000 mg/kg bw/day for both maternal toxicity and embryo/fetal development when administered orally during gestation to pregnant rats.

9.
Toxicol Rep ; 3: 310-327, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-28959552

RESUMEN

A toxicological evaluation of two novel bitter modifying flavour compounds, 3-(1-((3,5-dimethylisoxazol-4-yl)methyl)-1H-pyrazol-4-yl)-1-(3-hydroxybenzyl)imidazolidine-2,4-dione (S6821, CAS 1119831-25-2) and 3-(1-((3,5-dimethylisoxazol-4-yl)methyl)-1H-pyrazol-4-yl)-1-(3-hydroxybenzyl)-5,5-dimethylimidazolidine-2,4-dione (S7958, CAS 1217341-48-4), were completed for the purpose of assessing their safety for use in food and beverage applications. S6821 undergoes oxidative metabolism in vitro, and in rat pharmacokinetic studies both S6821 and S7958 are rapidly converted to the corresponding O-sulfate and O-glucuronide conjugates. S6821 was not found to be mutagenic or clastogenic in vitro, and did not induce micronuclei in bone marrow polychromatic erythrocytes in vivo. S7958, a close structural analog of S6821, was also found to be non-mutagenic in vitro. In short term and subchronic oral toxicity studies in rats, the no-observed-adverse-effect-level (NOAEL) for both S7958 and S6821 was 100 mg/kg bw/day (highest dose tested) when administered as a food ad-mix for either 28 or 90 consecutive days, respectively. Furthermore, S6821 demonstrated a lack of maternal toxicity, as well as adverse effects on fetal morphology at the highest dose tested, providing a NOAEL of 1000 mg/kg bw/day for both maternal toxicity and embryo/fetal development when administered orally during gestation to pregnant rats.

10.
Toxicol Rep ; 3: 501-512, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-28959573

RESUMEN

A toxicological evaluation of a umami flavour compound, 2-(((3-(2,3-dimethoxyphenyl)-1H-1,2,4-triazol-5-yl)thio)methyl)pyridine (S3643; CAS 902136-79-2), was completed for the purpose of assessing its safety for use in food and beverage applications. S3643 undergoes extensive oxidative metabolism in vitro with rat microsomes producing the S3643-sulfoxide and 4'-hydroxy-S3643 as the major metabolites. In incubations with human microsomes, the O-demethyl-S3643 and S3643-sulfoxide were produced as the major metabolites. In pharmacokinetic studies in rats, the S3643-sulfoxide represents the dominant biotransformation product. S3643 was not found to be mutagenic or clastogenic in vitro, and did not induce micronuclei in CHO-WBL cells. In subchronic oral toxicity studies in rats, the no-observed-adverse-effect-level (NOAEL) for S3643 was 100 mg/kg bw/day (highest dose tested) when administered in the diet for 90 consecutive days.

11.
Toxicol Rep ; 3: 841-860, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-28959612

RESUMEN

Toxicological evaluations of two N-alkyl benzamide umami flavour compounds, N-(heptan-4-yl)benzo[d][1,3]dioxole-5-carboxamide (S807, CAS 745047-51-2) and (R)-N-(1-methoxy-4-methylpentan-2-yl)-3,4-dimethylbenzamide (S9229, CAS 851669-60-8), were completed for the purpose of assessing their safety for use in food and beverage applications. Both S807 and S9229 undergo rapid oxidative metabolism by both rat and human liver microsomes in vitro. In pharmacokinetic studies in rats, the systemic exposure to S9229 on oral administration is very low at all doses (% F < 1%), while that of S807 demonstrated a non-linear dose dependence. In metabolism studies in rats, hydroxylation of the C-4 aryl methyl group was found to be the dominant metabolic pathway for S9229. The dominant metabolic pathway for S807 in the rat involved oxidative scission of the methylenedioxy moiety to produce the corresponding 3,4-dihydroxybenamide which is further converted by Phase II metabolic enzymes to the 3- and 4-O-methyl ethers as well as their corresponding glucuronides. Both S807 and S9229 were not found to be mutagenic or clastogenic in vitro, and did not induce micronuclei in polychromatic erythrocytes in vivo. In a subchronic oral toxicity study in rats, the no-observed-effect-level (NOEL) for S807 was 20 mg/kg bw/day when administered in the diet for 13 weeks. The no-observed-adverse-effect-level (NOAEL) for S9229 in rats was 100 mg/kg bw/day (highest dose tested) when administered in the diet for 28 consecutive days.

12.
Health Syst Reform ; 1(1): 72-88, 2015 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-31519086

RESUMEN

Abstract-This paper evaluates resource commitments to primary health care (PHC) by donors and selected governments between 1990-2011. Donor commitments to financing PHC are assessed by reclassifying OECD/CRS data on health assistance into spending on 'PHC Service Delivery' versus spending on 'Health System Strengthening'. Domestic spending on PHC is assessed using a case study approach and National Health Accounts for two major recipients of donor assistance, Ethiopia and Nigeria. Results are generally consistent with three simple hypotheses that guide the inquiry. First, though donor funding for health among LICs has mushroomed over the last decade, it remains a miniscule share of per capita spending targets prescribed by international forums to attain universal access to basic/essential PHC services. Relative to levels of domestic public spending in LICs, however, donor funding has considerably more significance as a potential lever to improve PHC efficiency. Second, as reflected in on-going debate in the literature, donor spending on broader 'health system strengthening' has not kept up with mushrooming financing of disease control programs. Third, at country level, where the 'rubber meets the road', allocative efficiency of donor and domestic spending on health is highly conditional on contextual factors, especially political will to improve financing and delivery of PHC services, and the process of managing and implementing public spending on PHC.

13.
Health Syst Reform ; 1(2): 155-166, 2015 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-31546306

RESUMEN

Abstract-Public-private partnerships (PPPs) seek to expand access to quality health services in ways that best leverage the capacities and resources of both sectors. There are few examples of PPPs in the hospital sector in developing countries, and little is known about how the involvement of the private sector transforms the delivery of health services in this context. In 2006, the government of Lesotho adopted a PPP approach for the health sector, contracting out to design, build, and operate a hospital network in its capital district. This case study examines differences between a government-run hospital and the PPP-run hospital that replaced it, using in-depth interviews with key informants, observation of management systems, and document review. Key informants emphasized changes in infrastructure, communication, human resource management, and organizational culture that improved quality and demand for services. Important drivers of improved performance included better defined policies and procedures, empowerment and training of managers and staff, and increased accountability. Well-functioning support systems kept the hospital clean and equipment functioning, reduced stock-outs, and allowed staff to do the jobs they were trained to do. The Lesotho PPP model provides insight into the mechanisms by which public-private partnerships may increase access and quality of care.

14.
Toxicol Rep ; 2: 1255-1264, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-28962468

RESUMEN

A toxicological evaluation of 4-amino-5-(3-(isopropylamino)-2,2-dimethyl-3-oxopropoxy)-2-methylquinoline-3-carboxylic acid(S9632; CAS 1359963-68-0), a flavour with modifying properties,was completed for the purpose of assessing its safety for use in food and beverage applications. No Phase I biotransformations of S9632 were observed in rat or human microsomes in vitro, and in rat pharmacokinetic studies, the compound was poorly orally bioavailable and rapidly eliminated. S9632 was not found to be mutagenic or clastogenic in vitro, and did not induce micronuclei or indicate interactions with the mitotic spindle in an in vivo mouse micronucleus assay at oral doses up to 2000 mg/kg. In subchronic oral toxicity studies in rats, the NOEL was 100 mg/kg/day (highest dose tested) for S9632 when administered as a food ad-mix for 90 consecutive days. Furthermore, S9632 demonstrated a lack of maternal toxicity, as well as adverse effects on fetal morphology at the highest dose tested, providing a NOEL of 1000 mg/kg/day for both maternal toxicity and embryo/fetal development when administered orally during gestation to pregnant rats.

15.
Toxicol Rep ; 2: 1291-1309, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-28962472

RESUMEN

A toxicological evaluation of a novel cooling agent, 2-(4-methylphenoxy)-N-(1H-pyrazol-3-yl)-N-(2-thienylmethyl) acetamide (S2227; CAS 1374760-95-8), was completed for the purpose of assessing its safety for use in food and beverage applications. S2227 undergoes rapid oxidative metabolism in vitro, and in rat and dog pharmacokinetic studies is rapidly converted to its component carboxylic acid and secondary amine. S2227 was not found to be mutagenic or clastogenic in vitro, and did not induce micronuclei in polychromatic erythrocytes in vivo. The secondary amine hydrolysis product, N-(2-thienylmethyl)-1H-pyrazol-3-amine (M179), was also evaluated for genotoxicity. In subchronic oral toxicity studies in rats, the no-observed-adverse-effect-level (NOAEL) for S2227 was 100 mg/kg/day (highest dose tested) when administered by oral gavage for 90 consecutive days. Furthermore, S2227 demonstrated a lack of maternal toxicity, as well as adverse effects on fetal morphology at the highest dose tested, providing a NOAEL of 1000 mg/kg/day for both maternal toxicity and embryo/fetal development when administered orally during gestation to pregnant rats.

16.
Hum Vaccin Immunother ; 10(9): 2691-6, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25483504

RESUMEN

Introduction of Haemophilus influenzae type b (Hib) vaccine in low- and middle-income countries has been limited by cost and availability of Hib conjugate vaccines for a long time. It was previously recognized by the Institute for Translational Vaccinology (Intravacc, originating from the former Vaccinology Unit of the National Institute of Public Health [RIVM] and the Netherlands Vaccine Institute [NVI]) that local production of a Hib conjugate vaccine would increase the affordability and sustainability of the vaccine and thereby help to speed up Hib introduction in these countries. A new affordable and a non-infringing production process for a Hib conjugate vaccine was developed, including relevant quality control tests, and the technology was transferred to a number of vaccine manufacturers in India, Indonesia, and China. As part of the Hib technology transfer project managed by Intravacc, a preclinical toxicity study was conducted in the Netherlands to test the safety and immunogenicity of this new Hib conjugate vaccine. The data generated by this study were used by the technology transfer partners to accelerate the clinical development of the new Hib conjugate vaccine. A repeated dose toxicity and local tolerance study in rats was performed to assess the reactogenicity and immunogenicity of a new Hib conjugate vaccine compared to a licensed vaccine. The results showed that the vaccine was well tolerated and immunogenic in rats, no major differences in both safety and immunogenicity in rats were found between the vaccine produced according to the production process developed by Intravacc and the licensed one. Rats may be useful to verify the immunogenicity of Hib conjugate vaccines and for preclinical evaluation. In general, nonclinical evaluation of the new Hib conjugate vaccine, including this proof of concept (safety and immunogenicity study in rats), made it possible for technology transfer partners, having implemented the original process with no changes in the manufacturing process and vaccine formulation, to start directly with phase 1 clinical trials.


Asunto(s)
Evaluación Preclínica de Medicamentos , Infecciones por Haemophilus/prevención & control , Vacunas contra Haemophilus/efectos adversos , Vacunas contra Haemophilus/inmunología , Haemophilus influenzae tipo b/inmunología , Transferencia de Tecnología , Animales , China , Infecciones por Haemophilus/microbiología , Vacunas contra Haemophilus/administración & dosificación , India , Indonesia , Países Bajos , Ratas Wistar , Vacunas Conjugadas/administración & dosificación , Vacunas Conjugadas/efectos adversos , Vacunas Conjugadas/inmunología
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