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1.
Environ Res ; 218: 114977, 2023 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-36463994

RESUMEN

In 1974, the United States established the Safe Drinking Water Act (SDWA) to protect consumers from potential exposure to drinking water contaminants associated with health risks. Each contaminant is assigned a health-based standard meant to reflect the maximum level at which an adverse human health outcome is unlikely; measurements beyond that level have greater potential to result in adverse health outcomes. Although there is extensive research on human health implications following water contaminant exposure, few studies have specifically examined associations between fetal health and municipal drinking water violations. Therefore, the objective of this study is to assess whether SDWA drinking water violations are associated with fetal health outcomes, including preterm birth (PTB), low birth weight (LBW), and term-low birth weight (tLBW), in the Commonwealth of Virginia. Singleton births (n = 665,984) occurring between 2007 and 2015 in Virginia were geocoded and assigned to a corresponding estimated water service area. Health-based (HB) and monitoring and reporting (MR) violations for 12 contaminants were acquired from the US EPA Safe Drinking Water Information System, with exposure defined at the approximate service area level to limit exposure misclassification. A logistic regression model for each birth outcome assessed potential relationships with SDWA violations. When examining the association between individual MR violations and birth outcomes, Nitrate-Nitrite (OR = 1.10; 95% CI = 1.02, 1.18, P = 0.01) was positively associated with PTB and the total coliform rule was negatively associated with tLBW (OR = 0.93; 95% CI = 0.87, 1.00, P = 0.04). These findings indicate that a lack of regular monitoring and reporting by water providers (resulting in monitoring and reporting violations) may be concealing health-based violations as these health concerns cannot be revealed without testing, suggesting a need for additional technical, managerial, and financial support to enable often-underfunded water systems to adhere to monitoring and reporting requirements meant to protect public health.


Asunto(s)
Agua Potable , Complicaciones del Embarazo , Nacimiento Prematuro , Femenino , Recién Nacido , Estados Unidos , Humanos , Agua Potable/análisis , Virginia/epidemiología , Recién Nacido de Bajo Peso
2.
Curr Psychol ; : 1-4, 2023 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-37359617

RESUMEN

The COVID-19 pandemic negatively impacted the mental health of people in Japan. Healthcare workers (HCWs) especially suffered from poor mental health, engaging with COVID-19 patients while protecting themselves from infection. However, a long-term assessment of their mental health in comparison to the general population remains to be conducted. This study evaluated and compared changes in mental health between these two populations over a six-month period. Measures of mental health, loneliness, hope and self-compassion were completed at baseline and at six-month follow-up. Two-way MANOVA (Time x Group) identified that no interaction effects were present. However, at baseline, HCWs had higher levels of mental health problems and loneliness, and lower levels of hope and self-compassion than the general population. Furthermore, a higher level of loneliness was found in HCWs at six months. These findings highlight strong feelings of loneliness in HCWs in Japan. Interventions such as digital social prescribing are recommended.

3.
J Environ Health ; 78(4): 14-7, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26638670

RESUMEN

Restroom internal door handles have the potential to become contaminated by pathogenic bacteria, particularly because frequent breakdowns occur in hand hygiene. Cleaning these door handles periodically could reduce this cross-contamination risk. The sustained effect following cleaning with chlorhexidine could be beneficial in restroom facilities as cleaning episodes are of necessity at time intervals. The cleaning efficacies and residual effects of Sani Cloth CHG 2% wipes were investigated in a double-blinded randomized crossover controlled trial in a school setting. No significant difference occurred in initial cleaning efficacy; however, following a six-hour period of use by pupils of the restroom facilities, the internal door handles wiped with Sani-Cloth CHG 2% wipes were significantly less contaminated than those with the control wipe (14% v. 32%, p = .02). Cleaning with Sani-Cloth CHG 2% wipes demonstrated significant improvements in the continuous cleanliness of restroom door handles during use with this simple and inexpensive technique.


Asunto(s)
Clorhexidina/farmacología , Desinfectantes/farmacología , Instituciones Académicas , Cuartos de Baño , Estudios Cruzados , Método Doble Ciego
4.
Artículo en Inglés | MEDLINE | ID: mdl-38658049

RESUMEN

The British Thoracic Society 2015 guidelines on home oxygen use in adults have been pivotal in guiding clinicians on the use of long-term oxygen therapy in improving survival outcomes for patients. However, guidance for use of home oxygen in the palliative care setting has not been as robust owing to the lack of evidence-based studies. Therefore, this narrative review aims to provide a clinical framework on the use of palliative home oxygen therapy by considering its prognostic and symptomatic benefits as well as offering pragmatic advice for palliative home oxygen in end-of-life care.

5.
Eur J Anaesthesiol ; 30(5): 216-21, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23511956

RESUMEN

CONTEXT: Laryngoscope handles are a potential vector for infection transmission and require adequate decontamination. OBJECTIVE: To establish an effective cleaning regimen for laryngoscope handles. DESIGN: Three laboratory studies and an audit cycle. SETTING: The Queen Elizabeth Hospital, King's Lynn, UK. MATERIALS: Twenty Heine laryngoscope handles. INTERVENTIONS: Twenty laryngoscope handles were contaminated with microbial broth and then disinfected with chemical wipes, either using Sani-Cloth CHG 2% (chlorhexidine 2%/alcohol 70%) or Tuffie 5 wipes. This was repeated with an interval of 24 h between cleaning and contamination. A further experiment repeatedly re-contaminated the handles at varying time intervals after cleaning. The audit established the current level of contamination of laryngoscope handles within the hospital, and this was repeated following a change in cleaning protocol. MAIN OUTCOME MEASURES: Bacterial growth on agar plates was counted as the number of colony forming units. RESULTS: Both Sani-Cloth CHG 2% and Tuffie 5 wipes were effective against microorganisms, including methicillin-resistant Staphylococcus aureus, immediately following wiping (P = 0.002). However, the chlorhexidine wipes also had a residual effect such that after wiping, the handle remained sterile following further contamination and this effect persisted for 24 h. Audit following the introduction of this practice showed significant improvements in the incidence and extent of contamination compared with the previous disinfection practice (P<0.002). CONCLUSION: Decontamination with Sani-Cloth CHG 2% wipes confers additional advantages over routine autoclaving or handle disposal, due to a residual effect. Autoclaving handles may be desirable on a scheduled basis and if Clostridium difficile is encountered.


Asunto(s)
Clorhexidina/farmacología , Descontaminación/métodos , Desinfectantes/farmacología , Laringoscopios , Auditoría Médica
6.
Postgrad Med J ; 88(1038): 205-9, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22366394

RESUMEN

INTRODUCTION: Patients presenting with peritonitis require rapid treatment initiation including laparotomy. In the older population, this often leads to Hartmann's procedure being performed. The decision to perform surgery may be a difficult, multidisciplinary decision balancing premorbid comorbidity and quality of life with knowledge of the postoperative outcome. However, the evidence for survival outcome of emergency surgery based on age is lacking. The aim of this study was therefore to assess the survival implication of age and other prognostic factors on the outcome after Hartmann's procedure. METHODS: A retrospective review of prospectively collected data of all patients undergoing emergency (National Confidential Enquiry into Patient Outcome and Death category 1-3) Hartmann's procedure in one NHS Health Board over a 5-year period. RESULTS: 129 patients underwent Hartmann's procedure between November 2004 and November 2009. The largest group, 61 patients (47.3%) had the procedure performed for perforated sigmoid diverticular disease. When examined at 5-year stratifications around the median, the most significant survival difference was seen at the age of 75 years (log rank χ(2) 11.246, p=0.001). Patients over 75 years had median survival significantly lower than those aged <75 years (p<0.001). However, Cox regression analysis showed that preoperative American Society of Anesthesiologists (ASA) status and haemoglobin were more significant independent predictors of mortality than this age strata (p=0.001 and 0.045 vs 0.660, respectively), adjusting for diagnosis. DISCUSSION: ASA grade and common blood abnormalities were more predictive of mortality after Hartmann's procedure than the most significant age stratification. Furthermore, age was not independently associated with survival. It would therefore be unreasonable to refuse Hartmann's procedure based on an age alone.


Asunto(s)
Cirugía Colorrectal/mortalidad , Cirugía Colorrectal/métodos , Hemoglobinas/efectos adversos , Peritonitis/cirugía , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Anastomosis Quirúrgica/métodos , Tratamiento de Urgencia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento
7.
Artículo en Inglés | MEDLINE | ID: mdl-36231737

RESUMEN

As awareness of mental health increases worldwide, how to improve mental health has begun to be discussed in many countries. Stress is known to cause diverse physical and mental health problems, including psychopathologies. On the other hand, our previous studies identified that self-compassion, kindness and understanding towards oneself are key components for good mental health in many populations, including Japanese workers. The government reports that Japanese workers suffer from high rates of mental health problems. However, the mechanism of how self-compassion helps their mental health remains to be evaluated. Accordingly, this study aimed to elucidate how self-compassion intervenes in pathways from stress to psychopathologies, namely depression and anxiety. One hundred and sixty-five Japanese workers completed an online survey regarding self-compassion, depression, anxiety and stress. Correlation and path analyses were conducted. These four variables were significantly inter-related. While self-compassion mediated the pathway from stress to depression, it did not mediate the pathway from stress to anxiety. These exploratory insights assist in understanding the mechanism of how self-compassion improves mental health and inform effective methods to implement self-compassion interventions to the Japanese workforce.


Asunto(s)
Depresión , Empatía , Ansiedad/psicología , Depresión/epidemiología , Depresión/psicología , Humanos , Japón , Autocompasión
8.
J Patient Saf ; 18(2): e387-e392, 2022 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-33512864

RESUMEN

OBJECTIVES: Guidewire retention during central venous catheter (CVC) insertion is considered a "never event." We analyzed the National Health Service England Never Event database (2004-2015) to explore the process of guidewire retention and identify potential preventative measures. METHODS: We performed a systematic analysis of reported retained guidewire incidents by 3 independent reviewers. RESULTS: There was a rising frequency of reported retained CVC guidewires, with an average of 2 never events per month. Only 11% of retained guidewires are identified during the procedure itself, with the remainder identified during equipment clear-up (6%), after the procedure (4%), at the first check radiograph (23%), or after the first radiograph (55%). In 59 cases, the grade of the operator was reported, and among these, 88% were inserted by trainee doctors. Analysis of causative factors was only possible for 38 cases, and of these, operator's mistake (32%), operator/human error (16%), and distraction (16%) were the most common. Of 163 reported cases, preventative measures instigated were actions taken against the individual clinician (36%), departmental actions such as investigations, additional teaching or reminders (37%), and additional checklists (27%). CONCLUSIONS: Most retained guidewires are discovered after the procedure. Despite the introduction of safety measures, guidewire retention still occurs because the checks, alerts, reminders, and additional checklists all solely rely on the operator remembering not to make the mistake. System changes or design modifications to the CVC equipment are needed to prevent guidewire retention, this being at the top of the hierarchy of intervention effectiveness.


Asunto(s)
Cateterismo Venoso Central , Catéteres Venosos Centrales , Cateterismo Venoso Central/efectos adversos , Catéteres Venosos Centrales/efectos adversos , Inglaterra , Humanos , Errores Médicos , Medicina Estatal
9.
Respir Care ; 63(4): 424-429, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29511036

RESUMEN

BACKGROUND: Unintentional extubation is a well-documented and potentially life-threatening phenomenon. There is little research into the factors that lead to unintentional extubation, and therefore how to prevent it. Endotracheal tubes (ETTs) are commonly secured with 1 cm twill tape, but there is little evidence on how to best tie them in place. We have devised a new knot for securing these tubes in place, and we have assessed its degree of slippage when exposed to both perpendicular and sliding forces in comparison with other commonly used knots. METHODS: We constructed a weighted apparatus to test the effects of these forces and measure whether conventional ETTs slipped. We tested the knots both wet and dry to better simulate the clinical environment. We also conducted a manual manipulation test in which a single operator attempted to slide the knot along the ETT. Each knot was tested 10 times for the weight test under both wet and dry conditions, and 8 times for the slip test. RESULTS: The normal knot slipped when weighted both wet and dry, while the clove hitch failed the weight test only when wet. Both the modified cow hitch and double hitch withstood all weights. Only the double hitch did not slip under any circumstances on either test. CONCLUSIONS: The new double hitch was superior to all conventional knots tested. It did not slip under any conditions and therefore may be of use to prevent unintentional extubation, particularly in the ICU setting.


Asunto(s)
Intubación Intratraqueal/instrumentación , Ensayo de Materiales/métodos , Cinta Quirúrgica , Extubación Traqueal , Falla de Equipo , Humanos , Intubación Intratraqueal/efectos adversos , Intubación Intratraqueal/métodos
11.
Stem Cells Dev ; 13(6): 694-715, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15684837

RESUMEN

To identify genes that may be involved in the process of human embryonic stem cell (hESC) differentiation, we profiled gene expression by expressed sequenced tag (EST) enumeration and massively parallel signature sequencing (MPSS) using RNA samples from feeder-free cultures of undifferentiated (passages 40-50) and differentiated (day 14) H1, H7, and H9 lines. MPSS and EST scan analysis showed good concordance and identified a large number of genes that changed rapidly as cultures transition from a pluripotent to a differentiated state. These included known and unknown ES cell-specific genes as well as a large number of known genes that were altered as cells differentiate. A subset of genes that were either up- or down-regulated were selected and their differential expression confirmed by a variety of independent methods, including comparison of expression after further differentiation, publicly available databases, and direct assessments by reverse transcriptase (RT)-PCR and immunocytochemistry. The analysis identified markers unique to the hESC and embryoid bodies (hEBs) stage as well as signaling pathways that likely regulate differentiation. The data generated can be used to monitor the state of hESC isolated by different laboratories using independent methods and maintained under differing culture conditions.


Asunto(s)
Embrión de Mamíferos/citología , Etiquetas de Secuencia Expresada , Perfilación de la Expresión Génica , Células Madre/citología , Técnicas de Cultivo de Célula/métodos , Diferenciación Celular , Línea Celular , Células Cultivadas , Mapeo Cromosómico/métodos , Cromosomas Humanos Par 12 , Bases de Datos como Asunto , Regulación de la Expresión Génica , Genoma Humano , Humanos , Inmunohistoquímica , Familia de Multigenes , ARN/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transducción de Señal , Regulación hacia Arriba
12.
Transplantation ; 78(4): 509-15, 2004 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-15446308

RESUMEN

BACKGROUND: Major histocompatibility complex (MHC) molecules are essential determinants of beta-cell destruction in type 1 diabetes (T1D). MHC class I- or class II-null nonobese diabetic (NOD) mice do not spontaneously develop autoimmune diabetes and are resistant to adoptive transfer of disease. Both CD4+ and CD8+ T cells are associated with graft destruction after syngeneic islet transplantation. MHC molecules within the graft (i.e., on beta-cells or donor lymphocytes) may influence the interactions between antigen presenting cells and effector T cells and, therefore, the survival outcome of the graft. METHODS: Donor islets from NOD mice deficient in one or both of beta2-microglobulin and class II transactivator genes were transplanted into diabetic NOD mice. Immunohistochemistry was performed to identify the phenotype of infiltrating cells and to assess graft insulin production. The presence of cytokines in the grafts was assayed by reverse transcription polymerase chain reaction. RESULTS: MHC class II-null islets demonstrated rates of rejection comparable with control wild-type (wt) islets. In contrast, MHC class I- and II-null islets demonstrated indefinite survival (over 100 days). Infiltrates of both failed and surviving grafts were comprised of cytotoxic lymphocytes (CTL), helper T cells, and macrophages. Grafts also showed the presence of both Th1- and Th2-type cytokines (interleukin [IL]-2, IL-4, IL-10, and interferon-gamma), independent of graft status. CONCLUSIONS: These results demonstrate the primary importance of MHC class I molecules in the pathogenesis of diabetes recurrence postislet transplantation. Conversely, MHC class II expression is not a necessary mechanistic component of transplant destruction. In addition, these results implicate MHC class I-restricted CTLs but not MHC class II-restricted T cells in disease recurrence.


Asunto(s)
Diabetes Mellitus Tipo 1/etiología , Trasplante de Islotes Pancreáticos , Complejo Mayor de Histocompatibilidad/fisiología , Animales , Citocinas/fisiología , Diabetes Mellitus Tipo 1/terapia , Supervivencia de Injerto , Ratones , Ratones Endogámicos NOD , Proteínas Nucleares/fisiología , Recurrencia , Células TH1/inmunología , Células Th2/inmunología , Transactivadores/fisiología , Microglobulina beta-2/fisiología
14.
Artículo en Inglés | MEDLINE | ID: mdl-24814001

RESUMEN

Quantification of the pyrethroid deltamethrin (DLM) in small (100 µL) biological samples from rodents is essential for toxicokinetic studies of trace levels of the insecticide in foods. Such empirical kinetic data are necessary for construction of valid physiologically-based toxicokinetic models. There are no validated methods in the literature for determining deltamethrin in 100 µL plasma and brain samples. Plasma and brain samples were stabilized using sodium fluoride as an esterase inhibitor, and the DLM was extracted by protein precipitation using acetonitrile and phosphoric acid. The samples were vortexed, centrifuged, evaporated to dryness, and reconstituted in toluene prior to injection into a gas chromatograph equipped with a quadrupole mass analyzer. Samples were ionized via electron capture in the negative ion mode using methane, and the molecular ion and fragment ions of DLM were monitored using Selected-Ion Monitoring (SIM) for quantitation and verification of the analyte. Cis-permethrin was used as the internal standard for the method, which was validated according to current US FDA guidelines. Linearity was determined between 0.3 and 1,000 ng/mL, with a limit of detection of 150 pg/mL. The intra- and inter-batch variation for precision (as % relative standard deviation, RSD) and accuracy (as % bias) of the method were better than 20% at the limit of quantitation and better than 15% across the remaining linear range (n=18), with recoveries of 113% and 68% for plasma and brain respectively. Benchtop stability, autosampler stability, and freeze/thaw stability studies of the method (over a 3-day freeze/thaw cycle) were found to be within the acceptance criteria of 20% RSD and bias. This optimized method was applied to the quantitation of DLM in plasma and brain homogenate samples obtained up to 12h after oral dosing of Sprague-Dawley rats with 1mg DLM/kg body weight.


Asunto(s)
Química Encefálica/fisiología , Cromatografía de Gases y Espectrometría de Masas/métodos , Nitrilos/análisis , Nitrilos/sangre , Piretrinas/análisis , Piretrinas/sangre , Animales , Estabilidad de Medicamentos , Límite de Detección , Modelos Lineales , Masculino , Nitrilos/química , Piretrinas/química , Ratas , Ratas Sprague-Dawley , Reproducibilidad de los Resultados , Extracción en Fase Sólida , Espectrometría de Masa por Ionización de Electrospray/métodos
15.
PLoS One ; 7(5): e37004, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22623968

RESUMEN

Development of a human embryonic stem cell (hESC)-based therapy for type 1 diabetes will require the translation of proof-of-principle concepts into a scalable, controlled, and regulated cell manufacturing process. We have previously demonstrated that hESC can be directed to differentiate into pancreatic progenitors that mature into functional glucose-responsive, insulin-secreting cells in vivo. In this study we describe hESC expansion and banking methods and a suspension-based differentiation system, which together underpin an integrated scalable manufacturing process for producing pancreatic progenitors. This system has been optimized for the CyT49 cell line. Accordingly, qualified large-scale single-cell master and working cGMP cell banks of CyT49 have been generated to provide a virtually unlimited starting resource for manufacturing. Upon thaw from these banks, we expanded CyT49 for two weeks in an adherent culture format that achieves 50-100 fold expansion per week. Undifferentiated CyT49 were then aggregated into clusters in dynamic rotational suspension culture, followed by differentiation en masse for two weeks with a four-stage protocol. Numerous scaled differentiation runs generated reproducible and defined population compositions highly enriched for pancreatic cell lineages, as shown by examining mRNA expression at each stage of differentiation and flow cytometry of the final population. Islet-like tissue containing glucose-responsive, insulin-secreting cells was generated upon implantation into mice. By four- to five-months post-engraftment, mature neo-pancreatic tissue was sufficient to protect against streptozotocin (STZ)-induced hyperglycemia. In summary, we have developed a tractable manufacturing process for the generation of functional pancreatic progenitors from hESC on a scale amenable to clinical entry.


Asunto(s)
Técnicas de Cultivo Celular por Lotes/métodos , Diferenciación Celular/fisiología , Diabetes Mellitus Tipo 1/terapia , Células Madre Embrionarias/citología , Células Madre Embrionarias/trasplante , Células Secretoras de Insulina/citología , Análisis de Varianza , Animales , Criopreservación/métodos , Células Madre Embrionarias/fisiología , Citometría de Flujo , Técnica del Anticuerpo Fluorescente , Perfilación de la Expresión Génica , Humanos , Masculino , Ratones , Ratones SCID , Estreptozocina
16.
BMJ Support Palliat Care ; 1(3): 310-4, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24653476

RESUMEN

OBJECTIVE: The primary objective of the study was to determine the relative importance of place of death to patients with advanced cancer being treated at a cancer centre in England. METHODS: Demographic data were collected from the electronic patient record system, with additional information obtained from the patients themselves. Patients were questioned about a variety of end of life issues, including preferred place of death (PPD), and 'acceptable' places of death. They were also asked to rank the importance of factors previously linked to a 'good death'. RESULTS: 120 patients participated in the study. 51 (42.5%) patients stated that 'home' was their PPD, while 80 (67%) patients stated that home was an acceptable place of death. Patients from areas with worse deprivation scores were less likely to want to die at home than patients from areas with better deprivation scores (p=0.03). The most important factors associated with a good death were 'to have my pain/symptoms well controlled', 'to not be a burden to my family' and 'to have sorted out my personal affairs' respectively. Place of death was ranked as the seventh most important factor. DISCUSSION: Place of death is undoubtedly an important factor in achieving a good death for some patients and carers. However, for others a home death is either unimportant or to be avoided. The results of this study, and the results of similar studies, suggest that place of death may not be a good marker of the quality of end of life care.


Asunto(s)
Actitud Frente a la Muerte , Neoplasias , Prioridad del Paciente , Cuidado Terminal , Adulto , Anciano , Anciano de 80 o más Años , Inglaterra , Femenino , Servicios de Atención de Salud a Domicilio , Hospitales para Enfermos Terminales , Hospitalización , Humanos , Masculino , Persona de Mediana Edad , Características de la Residencia
17.
PLoS One ; 6(8): e23018, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21857983

RESUMEN

Human pluripotent stem cell (hPSC) lines have been considered to be homogeneously euploid. Here we report that normal hPSC--including induced pluripotent--lines are karyotypic mosaics of euploid cells intermixed with many cells showing non-clonal aneuploidies as identified by chromosome counting, spectral karyotyping (SKY) and fluorescent in situ hybridization (FISH) of interphase/non-mitotic cells. This mosaic aneuploidy resembles that observed in progenitor cells of the developing brain and preimplantation embryos, suggesting that it is a normal, rather than pathological, feature of stem cell lines. The karyotypic heterogeneity generated by mosaic aneuploidy may contribute to the reported functional and phenotypic heterogeneity of hPSCs lines, as well as their therapeutic efficacy and safety following transplantation.


Asunto(s)
Aneuploidia , Células Madre Pluripotentes/citología , Células Madre Pluripotentes/metabolismo , Animales , Técnicas de Cultivo de Célula , Línea Celular , Femenino , Humanos , Hibridación Fluorescente in Situ , Cariotipificación , Ratones , Cariotipificación Espectral
18.
Nat Biotechnol ; 26(4): 443-52, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18288110

RESUMEN

Development of a cell therapy for diabetes would be greatly aided by a renewable supply of human beta-cells. Here we show that pancreatic endoderm derived from human embryonic stem (hES) cells efficiently generates glucose-responsive endocrine cells after implantation into mice. Upon glucose stimulation of the implanted mice, human insulin and C-peptide are detected in sera at levels similar to those of mice transplanted with approximately 3,000 human islets. Moreover, the insulin-expressing cells generated after engraftment exhibit many properties of functional beta-cells, including expression of critical beta-cell transcription factors, appropriate processing of proinsulin and the presence of mature endocrine secretory granules. Finally, in a test of therapeutic potential, we demonstrate that implantation of hES cell-derived pancreatic endoderm protects against streptozotocin-induced hyperglycemia. Together, these data provide definitive evidence that hES cells are competent to generate glucose-responsive, insulin-secreting cells.


Asunto(s)
Técnicas de Cultivo de Célula/tendencias , Células Madre Embrionarias/citología , Glucosa/metabolismo , Células Secretoras de Insulina/citología , Células Secretoras de Insulina/metabolismo , Insulina/metabolismo , Ingeniería de Tejidos/tendencias , Animales , Diferenciación Celular , Proliferación Celular , Células Cultivadas , Células Madre Embrionarias/metabolismo , Células Madre Embrionarias/trasplante , Endodermo/citología , Endodermo/metabolismo , Humanos , Células Secretoras de Insulina/trasplante , Ratones , Páncreas Artificial/tendencias
19.
Stem Cells ; 23(10): 1468-78, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16123389

RESUMEN

Human embryonic stem cells (hESCs) derived from human blastocysts have an apparently unlimited proliferative capacity and can differentiate into ectoderm, mesoderm, and endoderm. As such, hESC lines have enormous potential for use in cell replacement therapies. It must first be demonstrated, however, that hESCs maintain a stable karyotype and phenotype and that gene expression is appropriately regulated. To date, different hESC lines exhibit similar patterns of expression of markers associated with pluripotent cells. However, the evaluation of epigenetic status of hESC lines has only recently been initiated. One example of epigenetic gene regulation is dosage compensation of the X chromosome in mammalian females. This is achieved through an epigenetic event referred to as X-chromosome inactivation (XCI), an event initiated upon cellular differentiation. We provide the first evidence that undifferentiated hESC lines exhibit different patterns of XCI.


Asunto(s)
Células Madre/metabolismo , Inactivación del Cromosoma X/fisiología , Aneuploidia , Azacitidina/análogos & derivados , Azacitidina/farmacología , Línea Celular , Cromatina/genética , Cromatina/metabolismo , Decitabina , Investigaciones con Embriones , Femenino , Perfilación de la Expresión Génica , Silenciador del Gen , Humanos , ARN Largo no Codificante , ARN no Traducido/efectos de los fármacos , ARN no Traducido/metabolismo , Células Madre/citología , Teratógenos/farmacología
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