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1.
Cochrane Database Syst Rev ; 11: CD013534, 2022 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-36373988

RESUMO

BACKGROUND: Eczema and food allergy are common health conditions that usually begin in early childhood and often occur in the same people. They can be associated with an impaired skin barrier in early infancy. It is unclear whether trying to prevent or reverse an impaired skin barrier soon after birth is effective for preventing eczema or food allergy. OBJECTIVES: Primary objective To assess the effects of skin care interventions such as emollients for primary prevention of eczema and food allergy in infants. Secondary objective To identify features of study populations such as age, hereditary risk, and adherence to interventions that are associated with the greatest treatment benefit or harm for both eczema and food allergy. SEARCH METHODS: We performed an updated search of the Cochrane Skin Specialised Register, CENTRAL, MEDLINE, and Embase in September 2021. We searched two trials registers in July 2021. We checked the reference lists of included studies and relevant systematic reviews, and scanned conference proceedings to identify further references to relevant randomised controlled trials (RCTs).  SELECTION CRITERIA: We included RCTs of skin care interventions that could potentially enhance skin barrier function, reduce dryness, or reduce subclinical inflammation in healthy term (> 37 weeks) infants (≤ 12 months) without pre-existing eczema, food allergy, or other skin condition. Eligible comparisons were standard care in the locality or no treatment. Types of skin care interventions could include moisturisers/emollients; bathing products; advice regarding reducing soap exposure and bathing frequency; and use of water softeners. No minimum follow-up was required. DATA COLLECTION AND ANALYSIS: This is a prospective individual participant data (IPD) meta-analysis. We used standard Cochrane methodological procedures, and primary analyses used the IPD dataset. Primary outcomes were cumulative incidence of eczema and cumulative incidence of immunoglobulin (Ig)E-mediated food allergy by one to three years, both measured at the closest available time point to two years. Secondary outcomes included adverse events during the intervention period; eczema severity (clinician-assessed); parent report of eczema severity; time to onset of eczema; parent report of immediate food allergy; and allergic sensitisation to food or inhalant allergen. MAIN RESULTS: We identified 33 RCTs comprising 25,827 participants. Of these, 17 studies randomising 5823 participants reported information on one or more outcomes specified in this review.  We included 11 studies, randomising 5217 participants, in one or more meta-analyses (range 2 to 9 studies per individual meta-analysis), with 10 of these studies providing IPD; the remaining 6 studies were included in the narrative results only.   Most studies were conducted at children's hospitals. Twenty-five studies, including all those contributing data to meta-analyses, randomised newborns up to age three weeks to receive a skin care intervention or standard infant skin care. Eight of the 11 studies contributing to meta-analyses recruited infants at high risk of developing eczema or food allergy, although the definition of high risk varied between studies. Durations of intervention and follow-up ranged from 24 hours to three years. All interventions were compared against no skin care intervention or local standard care. Of the 17 studies that reported information on our prespecified outcomes, 13 assessed emollients. We assessed most of the evidence in the review as low certainty and had some concerns about risk of bias. A rating of some concerns was most often due to lack of blinding of outcome assessors or significant missing data, which could have impacted outcome measurement but was judged unlikely to have done so. We assessed the evidence for the primary food allergy outcome as high risk of bias due to the inclusion of only one trial, where findings varied based on different assumptions about missing data. Skin care interventions during infancy probably do not change the risk of eczema by one to three years of age (risk ratio (RR) 1.03, 95% confidence interval (CI) 0.81 to 1.31; risk difference 5 more cases per 1000 infants, 95% CI 28 less to 47 more; moderate-certainty evidence; 3075 participants, 7 trials) or time to onset of eczema (hazard ratio 0.86, 95% CI 0.65 to 1.14; moderate-certainty evidence; 3349 participants, 9 trials). Skin care interventions during infancy may increase the risk of IgE-mediated food allergy by one to three years of age (RR 2.53, 95% CI 0.99 to 6.49; low-certainty evidence; 976 participants, 1 trial) but may not change risk of allergic sensitisation to a food allergen by age one to three years (RR 1.05, 95% CI 0.64 to 1.71; low-certainty evidence; 1794 participants, 3 trials). Skin care interventions during infancy may slightly increase risk of parent report of immediate reaction to a common food allergen at two years (RR 1.27, 95% CI 1.00 to 1.61; low-certainty evidence; 1171 participants, 1 trial); however, this was only seen for cow's milk, and may be unreliable due to over-reporting of milk allergy in infants. Skin care interventions during infancy probably increase risk of skin infection over the intervention period (RR 1.33, 95% CI 1.01 to 1.75; risk difference 17 more cases per 1000 infants, 95% CI one more to 38 more; moderate-certainty evidence; 2728 participants, 6 trials) and may increase the risk of infant slippage over the intervention period (RR 1.42, 95% CI 0.67 to 2.99; low-certainty evidence; 2538 participants, 4 trials) and stinging/allergic reactions to moisturisers (RR 2.24, 95% 0.67 to 7.43; low-certainty evidence; 343 participants, 4 trials), although CIs for slippages and stinging/allergic reactions were wide and include the possibility of no effect or reduced risk. Preplanned subgroup analyses showed that the effects of interventions were not influenced by age, duration of intervention, hereditary risk, filaggrin (FLG) mutation, chromosome 11 intergenic variant rs2212434, or classification of intervention type for risk of developing eczema. We could not evaluate these effects on risk of food allergy. Evidence was insufficient to show whether adherence to interventions influenced the relationship between skin care interventions and eczema or food allergy development. AUTHORS' CONCLUSIONS: Based on low- to moderate-certainty evidence, skin care interventions such as emollients during the first year of life in healthy infants are probably not effective for preventing eczema; may increase risk of food allergy; and probably increase risk of skin infection. Further study is needed to understand whether different approaches to infant skin care might prevent eczema or food allergy.


Assuntos
Eczema , Hipersensibilidade Alimentar , Hipersensibilidade a Leite , Feminino , Animais , Bovinos , Emolientes/uso terapêutico , Eczema/prevenção & controle , Eczema/tratamento farmacológico , Hipersensibilidade Alimentar/prevenção & controle , Alérgenos/uso terapêutico
2.
Clin Exp Allergy ; 51(3): 402-418, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33550675

RESUMO

OBJECTIVE: Eczema and food allergy start in infancy and have shared genetic risk factors that affect skin barrier. We aimed to evaluate whether skincare interventions can prevent eczema or food allergy. DESIGN: A prospectively planned individual participant data meta-analysis was carried out within a Cochrane systematic review to determine whether skincare interventions in term infants prevent eczema or food allergy. DATA SOURCES: Cochrane Skin Specialised Register, CENTRAL, MEDLINE, Embase and trial registries to July 2020. ELIGIBILITY CRITERIA FOR SELECTED STUDIES: Included studies were randomized controlled trials of infants <1 year with healthy skin comparing a skin intervention with a control, for prevention of eczema and food allergy outcomes between 1 and 3 years. RESULTS: Of the 33 identified trials, 17 trials (5823 participants) had relevant outcome data and 10 (5154 participants) contributed to IPD meta-analysis. Three of seven trials contributing to primary eczema analysis were at low risk of bias, and the single trial contributing to primary food allergy analysis was at high risk of bias. Interventions were mainly emollients, applied for the first 3-12 months. Skincare interventions probably do not change risk of eczema by age 1-3 years (RR 1.03, 95% CI 0.81, 1.31; I2 =41%; moderate certainty; 3075 participants, 7 trials). Sensitivity analysis found heterogeneity was explained by increased eczema in a trial of daily bathing as part of the intervention. It is unclear whether skincare interventions increase risk of food allergy by age 1-3 years (RR 2.53, 95% CI 0.99 to 6.47; very low certainty; 996 participants, 1 trial), but they probably increase risk of local skin infections (RR 1.34, 95% CI 1.02, 1.77; I2 =0%; moderate certainty; 2728 participants, 6 trials). CONCLUSION: Regular emollients during infancy probably do not prevent eczema and probably increase local skin infections.


Assuntos
Dermatite Atópica/prevenção & controle , Emolientes/uso terapêutico , Hipersensibilidade Alimentar/prevenção & controle , Humanos , Lactente , Recém-Nascido , Higiene da Pele , Dermatopatias Infecciosas/epidemiologia , Sabões , Abrandamento da Água
3.
Cytokine ; 138: 155357, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33153894

RESUMO

IL-23 is an inflammatory cytokine that plays an essential role in Th17 immunity by enhancing Th17 cell proliferation and survival, and Th17 cytokine production. IL-23 has pathogenic roles in the development of Th17-mediated inflammatory diseases including psoriasis. Despite successful treatment of psoriasis by blocking IL-23, the regulation of IL-23 expression in psoriasis patients is largely unknown. Dendritic cells are generally considered to be the primary source of IL-23 in psoriasis. While high levels of IL-23 are found in psoriatic epidermis, IL-23 expression in psoriatic keratinoctyes remains a controversial issue. In this study, we demonstrated that IL-23 production is induced by a combination of TNFα and IL-17A in human keratinocytes. Additionally, this IL-23 induction by TNFα and IL-17A is further increased in psoriatic keratinocytes and is enhanced by EGFR signaling. Although IL-23 is also robustly induced by toll-like receptor agonists in dendritic cells and macrophages, IL-23 expression in these cell types is not regulated by TNFα, IL-17A, and EGFR signaling. Given that IL-23 is essential for maintaining Th17 activation, IL-23 induction by TNFα, IL-17A, and EGF in keratinocytes could play an important pathological role in psoriasis pathogenesis as well as the cutaneous rash associated with EGFR inhibition therapy.


Assuntos
Fator de Crescimento Epidérmico/biossíntese , Regulação da Expressão Gênica , Interleucina-17/biossíntese , Subunidade p19 da Interleucina-23/biossíntese , Queratinócitos/metabolismo , Fator de Necrose Tumoral alfa/biossíntese , Biópsia , Proliferação de Células , Citocinas/metabolismo , Células Dendríticas/metabolismo , Epiderme/metabolismo , Humanos , Interleucina-1/metabolismo , Monócitos/metabolismo , Psoríase/metabolismo , Transdução de Sinais , Pele/patologia , Células THP-1/metabolismo , Células Th17/imunologia
4.
Cochrane Database Syst Rev ; 2: CD013534, 2021 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-33545739

RESUMO

BACKGROUND: Eczema and food allergy are common health conditions that usually begin in early childhood and often occur together in the same people. They can be associated with an impaired skin barrier in early infancy. It is unclear whether trying to prevent or reverse an impaired skin barrier soon after birth is effective in preventing eczema or food allergy. OBJECTIVES: Primary objective To assess effects of skin care interventions, such as emollients, for primary prevention of eczema and food allergy in infants Secondary objective To identify features of study populations such as age, hereditary risk, and adherence to interventions that are associated with the greatest treatment benefit or harm for both eczema and food allergy. SEARCH METHODS: We searched the following databases up to July 2020: Cochrane Skin Specialised Register, CENTRAL, MEDLINE, and Embase. We searched two trials registers and checked reference lists of included studies and relevant systematic reviews for further references to relevant randomised controlled trials (RCTs). We contacted field experts to identify planned trials and to seek information about unpublished or incomplete trials. SELECTION CRITERIA: RCTs of skin care interventions that could potentially enhance skin barrier function, reduce dryness, or reduce subclinical inflammation in healthy term (> 37 weeks) infants (0 to 12 months) without pre-existing diagnosis of eczema, food allergy, or other skin condition were included. Comparison was standard care in the locality or no treatment. Types of skin care interventions included moisturisers/emollients; bathing products; advice regarding reducing soap exposure and bathing frequency; and use of water softeners. No minimum follow-up was required. DATA COLLECTION AND ANALYSIS: This is a prospective individual participant data (IPD) meta-analysis. We used standard Cochrane methodological procedures, and primary analyses used the IPD dataset. Primary outcomes were cumulative incidence of eczema and cumulative incidence of immunoglobulin (Ig)E-mediated food allergy by one to three years, both measured by the closest available time point to two years. Secondary outcomes included adverse events during the intervention period; eczema severity (clinician-assessed); parent report of eczema severity; time to onset of eczema; parent report of immediate food allergy; and allergic sensitisation to food or inhalant allergen. MAIN RESULTS: This review identified 33 RCTs, comprising 25,827 participants. A total of 17 studies, randomising 5823 participants, reported information on one or more outcomes specified in this review. Eleven studies randomising 5217 participants, with 10 of these studies providing IPD, were included in one or more meta-analysis (range 2 to 9 studies per individual meta-analysis). Most studies were conducted at children's hospitals. All interventions were compared against no skin care intervention or local standard care. Of the 17 studies that reported our outcomes, 13 assessed emollients. Twenty-five studies, including all those contributing data to meta-analyses, randomised newborns up to age three weeks to receive a skin care intervention or standard infant skin care. Eight of the 11 studies contributing to meta-analyses recruited infants at high risk of developing eczema or food allergy, although definition of high risk varied between studies. Durations of intervention and follow-up ranged from 24 hours to two years. We assessed most of this review's evidence as low certainty or had some concerns of risk of bias. A rating of some concerns was most often due to lack of blinding of outcome assessors or significant missing data, which could have impacted outcome measurement but was judged unlikely to have done so. Evidence for the primary food allergy outcome was rated as high risk of bias due to inclusion of only one trial where findings varied when different assumptions were made about missing data. Skin care interventions during infancy probably do not change risk of eczema by one to two years of age (risk ratio (RR) 1.03, 95% confidence interval (CI) 0.81 to 1.31; moderate-certainty evidence; 3075 participants, 7 trials) nor time to onset of eczema (hazard ratio 0.86, 95% CI 0.65 to 1.14; moderate-certainty evidence; 3349 participants, 9 trials). It is unclear whether skin care interventions during infancy change risk of IgE-mediated food allergy by one to two years of age (RR 2.53, 95% CI 0.99 to 6.47; 996 participants, 1 trial) or allergic sensitisation to a food allergen at age one to two years (RR 0.86, 95% CI 0.28 to 2.69; 1055 participants, 2 trials) due to very low-certainty evidence for these outcomes. Skin care interventions during infancy may slightly increase risk of parent report of immediate reaction to a common food allergen at two years (RR 1.27, 95% CI 1.00 to 1.61; low-certainty evidence; 1171 participants, 1 trial). However, this was only seen for cow's milk, and may be unreliable due to significant over-reporting of cow's milk allergy in infants. Skin care interventions during infancy probably increase risk of skin infection over the intervention period (RR 1.34, 95% CI 1.02 to 1.77; moderate-certainty evidence; 2728 participants, 6 trials) and may increase risk of infant slippage over the intervention period (RR 1.42, 95% CI 0.67 to 2.99; low-certainty evidence; 2538 participants, 4 trials) or stinging/allergic reactions to moisturisers (RR 2.24, 95% 0.67 to 7.43; low-certainty evidence; 343 participants, 4 trials), although confidence intervals for slippages and stinging/allergic reactions are wide and include the possibility of no effect or reduced risk. Preplanned subgroup analyses show that effects of interventions were not influenced by age, duration of intervention, hereditary risk, FLG mutation,  or classification of intervention type for risk of developing eczema. We could not evaluate these effects on risk of food allergy. Evidence was insufficient to show whether adherence to interventions influenced the relationship between skin care interventions and risk of developing eczema or food allergy. AUTHORS' CONCLUSIONS: Skin care interventions such as emollients during the first year of life in healthy infants are probably not effective for preventing eczema, and probably increase risk of skin infection. Effects of skin care interventions on risk of food allergy are uncertain. Further work is needed to understand whether different approaches to infant skin care might promote or prevent eczema and to evaluate effects on food allergy based on robust outcome assessments.


Assuntos
Eczema/prevenção & controle , Emolientes/uso terapêutico , Hipersensibilidade Alimentar/prevenção & controle , Higiene da Pele/métodos , Viés , Feminino , Proteínas Filagrinas , Hipersensibilidade Alimentar/imunologia , Humanos , Hipersensibilidade Imediata/imunologia , Imunoglobulina E/imunologia , Lactente , Recém-Nascido , Masculino , Hipersensibilidade a Leite/etiologia , Dermatopatias Infecciosas/epidemiologia , Sabões
5.
Dermatol Clin ; 40(2): 179-190, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35366971

RESUMO

Pediatric Sweet syndrome (SS) is thought to be a hypersensitivity reaction to an underlying inflammatory or infectious state and typically is diagnosed using criteria created for adult patients. Although more studies are needed to understand the etiology and natural course of pediatric SS, guidelines for work-up and treatment have been suggested. Herein, the available literature is reviewed and guidelines summarized for the clinical evaluation and management of pediatric SS.


Assuntos
Hipersensibilidade , Síndrome de Sweet , Adulto , Criança , Humanos , Síndrome de Sweet/diagnóstico , Síndrome de Sweet/tratamento farmacológico
6.
Dermatitis ; 31(5): 309-315, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32947459

RESUMO

BACKGROUND: Moisturizers possibly improve atopic dermatitis (AD) by restoration of skin barrier, although some have detrimental effects. OBJECTIVE: The aim of the study was to estimate the effects of several routine moisturizers on barrier functions. METHODS: This is a randomized, forearm-controlled, observer-blind study. Patients older than 12 years with clear to moderate AD were randomized to 1 of 4 moisturizers (Cetaphil Cream, Aveeno Eczema Therapy Moisturizing Cream, CeraVe Moisturizing Cream, Vaseline) applied to nonlesional skin of 1 forearm and no moisturizer to the opposite forearm for 4 weeks. Transepidermal water loss (TEWL), capacitance, pH, and TEWL after tape stripping were evaluated at weeks 0 and 4. In addition, participants without AD underwent baseline measurements only. RESULTS: Twenty patients with AD completed the study. Baseline measurements between the AD group and 10 non-AD controls were similar. After the intervention (AD group), mean TEWL improved in the treated forearm and worsened in the untreated one, but the difference was not significant. There was no significant change in pH or in TEWL after tape stripping. Capacitance significantly improved in the moisturizer forearm. The study was underpowered as recruitment fell short. CONCLUSIONS: The effects of moisturizers on nonlesional AD skin were small and need to be addressed when powering future studies. Broadening investigations beyond the classic barrier properties might be useful in future studies.


Assuntos
Dermatite Atópica/tratamento farmacológico , Emolientes/uso terapêutico , Absorção Cutânea/efeitos dos fármacos , Perda Insensível de Água/efeitos dos fármacos , Administração Tópica , Adulto , Dermatite Atópica/prevenção & controle , Feminino , Antebraço , Humanos , Masculino , Pessoa de Meia-Idade
7.
Artigo em Inglês | MEDLINE | ID: mdl-32843430

RESUMO

Although cutaneous squamous cell carcinoma (cSCC) is treatable in the majority of cases, deadly invasive and metastatic cases do occur. To date there are neither reliable predictive biomarkers of disease progression nor FDA-approved targeted therapies as standard of care. To address these issues, we screened patient-derived primary cultured cells from invasive/metastatic cSCC with 107 small-molecule inhibitors. In-house bioinformatics tools were used to cross-analyze drug responses and DNA mutations in tumors detected by whole-exome sequencing (WES). Aberrations in molecular pathways with evidence of potential drug targets were identified, including the Eph-ephrin and neutrophil degranulation signaling pathways. Using a screening panel of siRNAs, we identified EPHA6 and EPHA7 as targets within the Eph-ephrin pathway responsible for mitigating decreased cell viability. These studies form a plausible foundation for detecting biomarkers of high-risk progressive disease applicable in dermatopathology and for patient-specific therapeutic options for invasive/metastatic cSCC.


Assuntos
Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/metabolismo , Sobrevivência Celular/genética , Progressão da Doença , Expressão Gênica/genética , Regulação Neoplásica da Expressão Gênica/genética , Genômica/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Mutação/genética , Receptor EphA6/antagonistas & inibidores , Receptor EphA6/metabolismo , Receptor EphA7/antagonistas & inibidores , Receptor EphA7/metabolismo , Transdução de Sinais/genética , Neoplasias Cutâneas/genética , Bibliotecas de Moléculas Pequenas/farmacologia , Sequenciamento do Exoma/métodos
8.
JPEN J Parenter Enteral Nutr ; 43(7): 899-911, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30644566

RESUMO

BACKGROUND: Dietary intake sharply impacts the structure and function of the gut microbiota, which is important for childhood health. However, little is known about the microbiota of children who cannot eat by mouth. Standard enteral formulas for supplemental nutrition are low in fiber and high in processed sugars and are commonly associated with gastrointestinal side effects. In this pilot study, we examined the effects of plant-based enteral nutrition (PBEN) upon the gut bacteria of chronically ill children. METHODS: Ten children (median age 3.5 years, age range 2-8 years) dependent upon conventional enteral formula were transitioned to PBEN for 2 months. Microbial diversity within fecal samples collected before and after PBEN was assessed by 16S ribosomal RNA gene sequence analysis and was compared with rectal swabs from healthy children. Fecal short-chain fatty acids and bile acids were measured in parallel. RESULTS: Relative to control samples, fecal samples from study subjects were depleted of commensals (eg, Faecalibacterium) and enriched with pathogens (eg, Enterococcus). Postintervention samples from study subjects were more similar to healthy controls. Most subjects experienced PBEN-induced alterations in the gut microbiota, but these changes varied significantly across individuals. Clinical diaries indicated that PBEN was well tolerated, with improvement in symptoms noted in several subjects. CONCLUSION: Results from this pilot study suggest that PBEN is well tolerated and could improve the health of the microbiota in chronically ill children. This trial provides a rationale for systematic evaluation of PBEN in clinical trials of children who require supplemental nutrition.


Assuntos
Doença Crônica/terapia , Fibras na Dieta/farmacologia , Nutrição Enteral/métodos , Alimentos Formulados , Microbioma Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/efeitos dos fármacos , Plantas/química , Bactérias/genética , Bactérias/crescimento & desenvolvimento , Bactérias/metabolismo , Criança , Pré-Escolar , Ácidos Graxos Voláteis/metabolismo , Fezes/microbiologia , Feminino , Trato Gastrointestinal/microbiologia , Humanos , Masculino , Projetos Piloto , RNA Ribossômico 16S
9.
Am J Clin Dermatol ; 19(4): 559-584, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29488102

RESUMO

Nail psoriasis (NP) and nail lichen planus (NLP) can be limiting, stigmatizing and difficult to treat. Dermatologists commonly treat psoriasis and lichen planus but when associated onychodystrophy is present or is an isolated finding, some develop apprehension. The goal of this review is to develop therapeutic ladders to be used as a guide for the management of NP and NLP in everyday clinical practice. Evidence-based therapies for NP are robust and range from topical treatments to conventional systemic therapies (i.e., methotrexate, cyclosporine), new oral agents (i.e., apremilast and tofacitinib), and biologics. The literature for treatment of NLP is severely limited, with therapy mainly consisting of topical, intralesional, or systemic corticosteroids or methotrexate.


Assuntos
Líquen Plano/tratamento farmacológico , Doenças da Unha/tratamento farmacológico , Psoríase/tratamento farmacológico , Adulto , Medicina Baseada em Evidências , Humanos , Terapia a Laser
10.
PLoS One ; 10(11): e0142828, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26605546

RESUMO

Ice-free cryopreservation, known as vitrification, is an appealing approach for banking of adherent cells and tissues because it prevents dissociation and morphological damage that may result from ice crystal formation. However, current vitrification methods are often limited by the cytotoxicity of the concentrated cryoprotective agent (CPA) solutions that are required to suppress ice formation. Recently, we described a mathematical strategy for identifying minimally toxic CPA equilibration procedures based on the minimization of a toxicity cost function. Here we provide direct experimental support for the feasibility of these methods when applied to adherent endothelial cells. We first developed a concentration- and temperature-dependent toxicity cost function by exposing the cells to a range of glycerol concentrations at 21°C and 37°C, and fitting the resulting viability data to a first order cell death model. This cost function was then numerically minimized in our state constrained optimization routine to determine addition and removal procedures for 17 molal (mol/kg water) glycerol solutions. Using these predicted optimal procedures, we obtained 81% recovery after exposure to vitrification solutions, as well as successful vitrification with the relatively slow cooling and warming rates of 50°C/min and 130°C/min. In comparison, conventional multistep CPA equilibration procedures resulted in much lower cell yields of about 10%. Our results demonstrate the potential for rational design of minimally toxic vitrification procedures and pave the way for extension of our optimization approach to other adherent cell types as well as more complex systems such as tissues and organs.


Assuntos
Criopreservação/métodos , Crioprotetores , Células Endoteliais , Animais , Bovinos , Técnicas de Cultura de Células , Sobrevivência Celular , Crioprotetores/toxicidade , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Glicerol , Modelos Teóricos , Pressão Osmótica , Temperatura , Vitrificação
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