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1.
Genet Med ; : 101166, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38767059

RESUMEN

PURPOSE: The function of FAM177A1 and its relationship to human disease is largely unknown. Recent studies have demonstrated FAM177A1 to be a critical immune-associated gene. One previous case study has linked FAM177A1 to a neurodevelopmental disorder in four siblings. METHODS: We identified five individuals from three unrelated families with biallelic variants in FAM177A1. The physiological function of FAM177A1 was studied in a zebrafish model organism and human cell lines with loss-of-function variants similar to the affected cohort. RESULTS: These individuals share a characteristic phenotype defined by macrocephaly, global developmental delay, intellectual disability, seizures, behavioral abnormalities, hypotonia, and gait disturbance. We show that FAM177A1 localizes to the Golgi complex in mammalian and zebrafish cells. Intersection of the RNA-seq and metabolomic datasets from FAM177A1-deficient human fibroblasts and whole zebrafish larvae demonstrated dysregulation of pathways associated with apoptosis, inflammation, and negative regulation of cell proliferation. CONCLUSION: Our data sheds light on the emerging function of FAM177A1 and defines FAM177A1-related neurodevelopmental disorder as a new clinical entity.

2.
Support Care Cancer ; 29(5): 2537-2547, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-32949298

RESUMEN

OBJECTIVES: Head and neck (H&N) cancer patients experience significant acute side effects from treatment. This study evaluates prospectively collected patient-reported outcomes (PROs) in H&N patients undergoing radiotherapy (RT) to assess feasibility of electronically collecting PROs and to objectively document symptom acuity and trajectory during RT. MATERIALS AND METHODS: H&N patients undergoing radical RT at our multicentre institution completed a 12-item partial survey of the Vanderbilt Head & Neck Symptom Survey 2.0 prior to RT and weekly on RT. Between October 2016 and October 2018, 318 of 333 patients completed a baseline survey and at least one weekly survey. RESULTS: The average number of weekly questionnaires completed was 5 (range 1-8). The mean maximum symptom scores were highest for dysgeusia (5.8/10), pain (5.4/10), mucositis (4.8/10), weight loss due to swallowing (4.5/10) and mucus causing choking/gagging (4.3/10). On multivariate analysis, female gender, sinonasal, nasopharynx and oropharynx primaries were associated with a greater risk of moderate-severe pain (p < 0.05). Sinonasal, nasopharynx, oral cavity, oropharynx and thyroid primaries were associated with a greater risk of moderate-severe mucositis during radiation (p < 0.0001). Salivary gland, sinonasal, nasopharynx and oropharynx primaries and higher radiation dose were associated with a greater risk of moderate-severe dysgeusia (all p < 0.05). CONCLUSIONS: Electronic PRO collection during H&N cancer RT is feasible. H&N cancer patients experience significant symptoms during RT, and the most severe symptoms reported were dysgeusia, pain and mucositis. Oropharynx cancer patients reported the highest symptom scores during RT.


Asunto(s)
Neoplasias de Cabeza y Cuello/radioterapia , Medición de Resultados Informados por el Paciente , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos
3.
J Relig Health ; 58(6): 2208-2218, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31420835

RESUMEN

The purpose of this study is to extend the Sabin et al's. (Am J Public Health 105(9):1831-1841, 2015. https://doi.org/10.2105/AJPH.2015.302631) findings to examine the extent to which religiosity and/or geographic region is predictive of negative attitudes or beliefs toward lesbian, gay, bisexual, and asexual (LGB+) individuals. Secondary data from the Sexuality Implicit Association Test were analyzed. Data included only participants from 2013 to 2015 who identified "Healthcare - Diagnosing and Treating Practitioners" as their occupation (n = 1376). The results of a factorial ANOVA revealed significant group differences accounting for 22.4% of the variance in attitudes toward LGB+ individuals. Religiosity was a significant factor in determining negative attitudes toward LGB+ individuals. However, the study was underpowered (5.8%) to detect an effect of geographic location in determining negative attitudes toward LGB+ individuals. It is important to validate a tool that can adequately measure the common assumptions associated with both religion and geographic region. Additionally, medical educators need to learn how to recognize and address negative attitudes among their students.


Asunto(s)
Actitud del Personal de Salud , Bisexualidad , Personal de Salud/psicología , Homosexualidad , Ubicación de la Práctica Profesional , Religión , Adulto , Femenino , Homofobia , Humanos , Masculino , Persona de Mediana Edad , Prejuicio , Minorías Sexuales y de Género
4.
Muscle Nerve ; 58(6): 784-789, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-29981160

RESUMEN

INTRODUCTION: Many prognostic factors have been studied in carpal tunnel decompression, but most studies consider only a subset of variables. METHODS: Three thousand three hundred thirty-two operations were used to develop prognostic models, and 885 operations were used for validation. Outcome recorded on a Likert scale was dichotomized into success or failure. Modeling was performed with both logistic regression and artificial neural networks using 87 candidate variables. RESULTS: Both approaches produced predictive multivariate models for outcome with areas under a receiver operating characteristic curve of 0.7 in the validation data set. Patients with moderately severe nerve conduction abnormalities, night waking, a family history of carpal tunnel syndrome, a good response to corticosteroid injection, and women have better outcomes. Greater functional impairment, diabetes, hypertension, and surgery on the dominant hand are associated with poorer outcomes. DISCUSSION: A multivariate model partially predicts the outcome of carpal tunnel surgery, aids decision making, and helps to manage patient expectations. Muscle Nerve 58:784-789, 2018.


Asunto(s)
Síndrome del Túnel Carpiano , Descompresión Quirúrgica/métodos , Modelos Neurológicos , Medición de Resultados Informados por el Paciente , Resultado del Tratamiento , Adulto , Anciano , Anciano de 80 o más Años , Síndrome del Túnel Carpiano/diagnóstico , Síndrome del Túnel Carpiano/psicología , Síndrome del Túnel Carpiano/cirugía , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Conducción Nerviosa/fisiología , Valor Predictivo de las Pruebas , Curva ROC , Estudios Retrospectivos , Reino Unido , Adulto Joven
5.
Artículo en Inglés | MEDLINE | ID: mdl-29733467

RESUMEN

OBJECTIVES: To examine the prevalence, determinants, and impact of local school health management committees on implementation of minimum-recommended school health services delivery among basic and secondary schools in Ghana. METHODS: National level cross-sectional data from the first-ever assessment of Ghana Global-School Health Policies and Practices Survey was utilized. Complex sample analyses were used to quantify school-level implementation of recommended minimum package for health services delivery. RESULTS: Of 307 schools, 98% were basic and government run, and 33% offered at least half of the recommended health service delivery areas measured. Schools with a school health management committee (53%) were 4.8 (95% CI = 3.23-5.18) times as likely to offer at least 50% of the minimum health services package than schools that did not. CONCLUSIONS: There is significant deficit concerning delivery of school health services in schools across Ghana. However, school health management committees positively impact implementation of health service delivery. POLICY IMPLICATIONS: School health management committees provide a significant impact on delivery of school health services; thus, it is recommended that policy makers and programmers place greater emphasis on the value and need for these advisory boards in all Ghanaian schools.

6.
Lancet Oncol ; 18(6): 755-769, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28479233

RESUMEN

BACKGROUND: The tAnGo trial was designed to investigate the potential role of gemcitabine when added to anthracycline and taxane-containing adjuvant chemotherapy for early breast cancer. When this study was developed, gemcitabine had shown significant activity in metastatic breast cancer, and there was evidence of a favourable interaction with paclitaxel. METHODS: tAnGo was an international, open-label, randomised, phase 3 superiority trial that enrolled women aged 18 years or older with newly diagnosed, early-stage breast cancer who had a definite indication for chemotherapy, any nodal status, any hormone receptor status, Eastern Cooperative Oncology Group performance status of 0-1, and adequate bone marrow, hepatic, and renal function. Women were recruited from 127 clinical centres and hospitals in the UK and Ireland, and randomly assigned (1:1) to one of two treatment regimens: epirubicin, cyclophosphamide, and paclitaxel (four cycles of 90 mg/m2 intravenously administered epirubicin and 600 mg/m2 intravenously administered cyclophosphamide on day 1 every 3 weeks, followed by four cycles of 175 mg/m2 paclitaxel as a 3 h infusion on day 1 every 3 weeks) or epirubicin, cyclophosphamide, and paclitaxel plus gemcitabine (the same chemotherapy regimen as the other group, with the addition of 1250 mg/m2 gemcitabine to the paclitaxel cycles, administered intravenously as a 0·5 h infusion on days 1 and 8 every 3 weeks). Patients were randomly assigned by a central computerised deterministic minimisation procedure, with stratification by country, age, radiotherapy intent, nodal status, and oestrogen receptor and HER-2 status. The primary endpoint was disease-free survival and the trial aimed to detect 5% differences in 5-year disease-free survival between the treatment groups. Recruitment completed in 2004 and this is the final, intention-to-treat analysis. This trial is registered with EudraCT (2004-002927-41), ISRCTN (51146252), and ClinicalTrials.gov (NCT00039546). FINDINGS: Between Aug 22, 2001, and Nov 26, 2004, 3152 patients were enrolled and randomly assigned to epirubicin, cyclophosphamide, paclitaxel, and gemcitabine (gemcitabine group; n=1576) or to epirubicin, cyclophosphamide, and paclitaxel (control group; n=1576). 11 patients (six in the gemcitabine group and five in the control group) were ineligible because of pre-existing metastases and were therefore excluded from the analysis. At this protocol-specified final analysis (median follow-up 10 years [IQR 10-10]), 1087 disease-free survival events and 914 deaths had occurred. Disease-free survival did not differ significantly between the treatment groups at 10 years (65% [63-68] in the gemcitabine group vs 65% [62-67] in the control group), and median disease-free survival was not reached (adjusted hazard ratio 0·97 [95% CI 0·86-1·10], p=0·64). Toxicity, dose intensity, and a detailed safety substudy showed both regimens to be safe, deliverable, and tolerable. Grade 3 and 4 toxicities were reported at expected levels in both groups. The most common were neutropenia (527 [34%] of 1565 patients in the gemcitabine group vs 412 [26%] of 1567 in the control group), myalgia and arthralgia (207 [13%] vs 186 [12%]), fatigue (207 [13%] vs 152 [10%]), infection (202 [13%] vs 141 [9%]), vomiting (143 [9%] vs 108 [7%]), and nausea (132 [8%] vs 102 [7%]). INTERPRETATION: The addition of gemcitabine to anthracycline and taxane-based adjuvant chemotherapy at this dose and schedule confers no therapeutic advantage in terms of disease-free survival in early breast cancer, although it can cause increased toxicity. Therefore, gemcitabine has not been added to standard adjuvant chemotherapy in breast cancer for any subgroup. FUNDING: Cancer Research UK core funding for Clinical Trials Unit at the University of Birmingham, Eli Lilly, Bristol-Myers Squibb, and Pfizer.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/terapia , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Neoplasias de la Mama/química , Neoplasias de la Mama/patología , Quimioterapia Adyuvante , Ciclofosfamida/administración & dosificación , Desoxicitidina/administración & dosificación , Desoxicitidina/análogos & derivados , Supervivencia sin Enfermedad , Epirrubicina/administración & dosificación , Femenino , Estudios de Seguimiento , Humanos , Análisis de Intención de Tratar , Metástasis Linfática , Mastectomía Segmentaria , Persona de Mediana Edad , Paclitaxel/administración & dosificación , Radioterapia , Receptor ErbB-2/análisis , Receptores de Estrógenos/análisis , Receptores de Progesterona/análisis , Tasa de Supervivencia , Gemcitabina
9.
Proc Natl Acad Sci U S A ; 110(18): 7324-9, 2013 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-23589866

RESUMEN

Since the discovery of neural stem cells in the mammalian brain, there has been significant interest in understanding their contribution to tissue homeostasis at both the cellular and molecular level. Wnt/ß-catenin signaling is crucial for development of the central nervous system and has been implicated in stem cell maintenance in multiple tissues. Based on this, we hypothesized that the Wnt pathway likely controls neural stem cell maintenance and differentiation along the entire developmental continuum. To test this, we performed lineage tracing experiments using the recently developed tamoxifen-inducible Cre at Axin2 mouse strain to follow the developmental fate of Wnt/ß-catenin-responsive cells in both the embryonic and postnatal mouse brain. From as early as embryonic day 8.5 onwards, Axin2(+) cells can give rise to spatially and functionally restricted populations of adult neural stem cells in the subventricular zone. Similarly, progeny from Axin2(+) cells labeled from E12.5 contribute to both the subventricular zone and the dentate gyrus of the hippocampus. Labeling in the postnatal brain, in turn, demonstrates the persistence of long-lived, Wnt/ß-catenin-responsive stem cells in both of these sites. These results demonstrate the continued importance of Wnt/ß-catenin signaling for neural stem and progenitor cell formation and function throughout developmental time.


Asunto(s)
Células Madre Adultas/citología , Proteína Axina/metabolismo , Linaje de la Célula , Células-Madre Neurales/citología , Células-Madre Neurales/metabolismo , Vía de Señalización Wnt , beta Catenina/metabolismo , Células Madre Adultas/metabolismo , Animales , Animales Recién Nacidos , Giro Dentado/citología , Giro Dentado/metabolismo , Embrión de Mamíferos/citología , Embrión de Mamíferos/metabolismo , Integrasas/metabolismo , Ratones , Neuroglía/citología , Neuroglía/metabolismo , Coloración y Etiquetado , Factores de Tiempo
10.
Support Care Cancer ; 21(12): 3433-9, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23949840

RESUMEN

PURPOSE: The purpose of this study is to compare patient outcomes between a therapeutic versus a prophylactic gastrostomy tube (GT) placement approach in patients treated with concurrent systemic and radiation (SRT) therapy for head and neck cancer (HNC). METHODS: Outcomes were compared between all HNC patients treated with concurrent SRT from January 2001 to June 2009 from a center that only places GTs therapeutically when clinically necessary (center A) versus a center that generally places them prophylactically (center B). RESULTS: A total of 445 patients with HNC were identified, with 63 % from center A. As anticipated, GTs were placed less commonly in center A compared to B (31 versus 88 %; p < 0.001). Center B had a significantly higher number of GT complications (p < 0.001), including infection (16 versus 5 %), leakage (10 versus 2 %), and blockage (3 versus 1 %). Conversely, center A had a higher admission rate (27 versus 13 %, p = 0.001), most prominent for GT-related issues (15 versus 6 %). Center B had higher GT dependence at 90 days post-radiation therapy (34 versus 12 %; p < 0.001), but not at 1 year (11 versus 10 %; p = 0.74). There was no significant difference in the proportion of head and neck patients who had a 10 % weight loss at 1 year (compared to baseline) between centers A and B (42 versus 53 %, p = 0.07). There was no significant difference in the overall survival (A versus B, HR = 0.99; p = 0.96). CONCLUSION: A prophylactic GT approach results in exposing higher number of patients to GT complications. The higher rate of hospitalizations using a therapeutic approach suggests that patients are sicker when GTs are required. Given the similar weight loss and survival, a therapeutic approach at an earlier stage of need may be a preferable approach, when access to prompt GT placement is available.


Asunto(s)
Gastrostomía/métodos , Neoplasias de Cabeza y Cuello/terapia , Intubación Gastrointestinal/métodos , Apoyo Nutricional/métodos , Cuidados Paliativos/métodos , Anciano , Anticuerpos Monoclonales Humanizados/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carboplatino/administración & dosificación , Cetuximab , Cisplatino/uso terapéutico , Femenino , Fluorouracilo/administración & dosificación , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Neoplasias de Cabeza y Cuello/radioterapia , Humanos , Masculino , Persona de Mediana Edad , Pérdida de Peso
11.
Arch Biochem Biophys ; 527(1): 55-64, 2012 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-22910297

RESUMEN

Nanosecond pulsed electric field (nsPEF) is a novel modality for permeabilization of membranous structures and intracellular delivery of xenobiotics. We hypothesized that oxidative effects of nsPEF could be a separate primary mechanism responsible for bioeffects. ROS production in cultured cells and media exposed to 300-ns PEF (1-13 kV/cm) was assessed by oxidation of 2',7'-dichlorodihydrofluoresein (H(2)DCF), dihidroethidium (DHE), or Amplex Red. When a suspension of H(2)DCF-loaded cells was subjected to nsPEF, the yield of fluorescent 2',7'-dichlorofluorescein (DCF) increased proportionally to the pulse number and cell density. DCF emission increased with time after exposure in nsPEF-sensitive Jurkat cells, but remained stable in nsPEF-resistant U937 cells. In cell-free media, nsPEF facilitated the conversion of H(2)DCF into DCF. This effect was not related to heating and was reduced by catalase, but not by mannitol or superoxide dismutase. Formation of H(2)O(2) in nsPEF-treated media was confirmed by increased oxidation of Amplex Red. ROS increase within individual cells exposed to nsPEF was visualized by oxidation of DHE. We conclude that nsPEF can generate both extracellular (electrochemical) and intracellular ROS, including H(2)O(2) and possibly other species. Therefore, bioeffects of nsPEF are not limited to electropermeabilization; concurrent ROS formation may lead to cell stimulation and/or oxidative cell damage.


Asunto(s)
Permeabilidad de la Membrana Celular , Electroporación , Estrés Oxidativo , Especies Reactivas de Oxígeno/metabolismo , Animales , Células CHO , Línea Celular , Membrana Celular/metabolismo , Supervivencia Celular , Sistema Libre de Células/metabolismo , Cricetinae , Electroporación/métodos , Fluoresceínas/análisis , Fluoresceínas/metabolismo , Colorantes Fluorescentes/análisis , Colorantes Fluorescentes/metabolismo , Humanos , Peróxido de Hidrógeno/metabolismo , Células Jurkat , Oxidación-Reducción
12.
Bioelectromagnetics ; 33(5): 394-404, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22213081

RESUMEN

Previous studies have found that nanosecond pulsed electric field (nsPEF) exposure causes long-term permeabilization of the cell plasma membrane. In this study, we utilized the whole-cell patch-clamp method to study the nsPEF effect on currents of voltage-gated (VG) Ca(2+) and Na(+) channels (I(Ca) and I(Na)) in cultured GH3 and NG108 cells. We found that a single 300 or 600 ns pulse at or above 1.5-2 kV/cm caused prolonged inhibition of I(Ca) and I(Na). Concurrently, nsPEF increased a non-inactivating "leak" current (I(leak)), presumably due to the formation of nanoelectropores or larger pores in the plasma membrane. The nsPEF effects were similar in cells that were exposed intact and subsequently brought into the whole-cell recording configuration, and in cells that were first brought into the whole-cell configuration and then exposed. Although both I(leak) and the inhibition of VG currents were enhanced at higher E-field levels, these two nsPEF effects showed relatively weak correlation with each other. In some cells, I(leak) increased 10-fold or more while VG currents remained unchanged. At longer time intervals after exposure (5-15 min), I(Ca) and I(Na) could remain inhibited although I(leak) had largely recovered. The causal relation of nsPEF inhibitory effects on VG currents and permeabilization of the plasma membrane is discussed.


Asunto(s)
Canales de Calcio/metabolismo , Conductividad Eléctrica , Canales de Sodio/metabolismo , Animales , Línea Celular , Permeabilidad de la Membrana Celular , Ratones , Canales de Potasio/metabolismo , Ratas , Factores de Tiempo
13.
J Allergy Clin Immunol Pract ; 10(8): 2039-2051, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35777651

RESUMEN

BACKGROUND: Since 2010, patients and physicians have collaborated to understand unmet needs of patients with mast cell diseases, incorporating mastocytosis and mast cell activation disorders, which include mast cell activation syndromes. OBJECTIVE: This Open Innovation in Science project aims to expand understanding of the needs of patients affected by mast cell diseases, and encourage global communication among patient advocacy groups, physicians, researchers, industry, and government. A major aim is to support the scientific community's efforts to improve diagnosis, management, therapy, and patients' quality of life by addressing unmet needs. METHODS: In collaboration with mast cell disease specialists, 13 patient advocacy groups from 12 countries and regions developed lists of top patient needs. A core team of leaders from patient advocacy groups collected and analyzed the data and proposed possible actions to address patient needs. RESULTS: Findings identified similarities and differences among participating countries in unmet needs between patients with mastocytosis and those with mast cell activation syndromes. Issues emphasized struggles relating to the nature and rarity of mast cell diseases, their impact on quality of life, the diagnostic process, access to appropriate care, more effective treatment, and the need for research. CONCLUSIONS: Solutions vary across countries because situations differ, in particular regarding the existence of and access to centers of excellence and reference centers. Multifaceted mast cell activation syndrome barriers necessitate innovative approaches to improve access to appropriate care. The outcomes of this project should greatly support scientists and clinicians in their efforts to improve diagnosis, management, and treatment of patients with mastocytosis and mast cell activation disorders.


Asunto(s)
Trastornos de la Activación de los Mastocitos , Mastocitosis , Humanos , Mastocitos , Mastocitosis/diagnóstico , Mastocitosis/terapia , Calidad de Vida
14.
Orphanet J Rare Dis ; 16(1): 206, 2021 05 07.
Artículo en Inglés | MEDLINE | ID: mdl-33962631

RESUMEN

Decreased sequencing costs have led to an explosion of genetic and genomic data. These data have revealed thousands of candidate human disease variants. Establishing which variants cause phenotypes and diseases, however, has remained challenging. Significant progress has been made, including advances by the National Institutes of Health (NIH)-funded Undiagnosed Diseases Network (UDN). However, 6000-13,000 additional disease genes remain to be identified. The continued discovery of rare diseases and their genetic underpinnings provides benefits to affected patients, of whom there are more than 400 million worldwide, and also advances understanding the mechanisms of more common diseases. Platforms employing model organisms enable discovery of novel gene-disease relationships, help establish variant pathogenicity, and often lead to the exploration of underlying mechanisms of pathophysiology that suggest new therapies. The Model Organism Screening Center (MOSC) of the UDN is a unique resource dedicated to utilizing informatics and functional studies in model organisms, including worm (Caenorhabditis elegans), fly (Drosophila melanogaster), and zebrafish (Danio rerio), to aid in diagnosis. The MOSC has directly contributed to the diagnosis of challenging cases, including multiple patients with complex, multi-organ phenotypes. In addition, the MOSC provides a framework for how basic scientists and clinicians can collaborate to drive diagnoses. Customized experimental plans take into account patient presentations, specific genes and variant(s), and appropriateness of each model organism for analysis. The MOSC also generates bioinformatic and experimental tools and reagents for the wider scientific community. Two elements of the MOSC that have been instrumental in its success are (1) multidisciplinary teams with expertise in variant bioinformatics and in human and model organism genetics, and (2) mechanisms for ongoing communication with clinical teams. Here we provide a position statement regarding the central role of model organisms for continued discovery of disease genes, and we advocate for the continuation and expansion of MOSC-type research entities as a Model Organisms Network (MON) to be funded through grant applications submitted to the NIH, family groups focused on specific rare diseases, other philanthropic organizations, industry partnerships, and other sources of support.


Asunto(s)
Enfermedades no Diagnosticadas , Animales , Drosophila melanogaster , Humanos , Fenotipo , Enfermedades Raras/diagnóstico , Enfermedades Raras/genética , Pez Cebra
15.
J Membr Biol ; 236(1): 15-26, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20623351

RESUMEN

The exclusion of polar dyes by healthy cells is widely employed as a simple and reliable test for cell membrane integrity. However, commonly used dyes (propidium, Yo-Pro-1, trypan blue) cannot detect membrane defects which are smaller than the dye molecule itself, such as nanopores that form by exposure to ultrashort electric pulses (USEPs). Instead, here we demonstrate that opening of nanopores can be efficiently detected and studied by fluorescent measurement of Tl(+) uptake. Various mammalian cells (CHO, GH3, NG108), loaded with a Tl(+)-sensitive fluorophore FluxOR and subjected to USEPs in a Tl(+)-containing bath buffer, displayed an immediate (within <100 ms), dose-dependent surge of fluorescence. In all tested cell lines, the threshold for membrane permeabilization to Tl(+) by 600-ns USEP was at 1-2 kV/cm, and the rate of Tl(+) uptake increased linearly with increasing the electric field. The lack of concurrent entry of larger dye molecules suggested that the size of nanopores is less than 1-1.5 nm. Tested ion channel inhibitors as well as removal of the extracellular Ca(2+) did not block the USEP effect. Addition of a Tl(+)-containing buffer within less than 10 min after USEP also caused a fluorescence surge, which confirms the minutes-long lifetime of nanopores. Overall, the technique of fluorescent detection of Tl(+) uptake proved highly effective, noninvasive and sensitive for visualization and analysis of membrane defects which are too small for conventional dye uptake detection methods.


Asunto(s)
Membrana Celular/química , Electroporación/métodos , Colorantes Fluorescentes/química , Talio/química , Animales , Células CHO , Calcio/química , Calcio/metabolismo , Membrana Celular/metabolismo , Cricetinae , Cricetulus , Colorantes Fluorescentes/farmacología , Ratones , Ratas , Talio/metabolismo
16.
Biochem Biophys Res Commun ; 385(2): 181-6, 2009 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-19450553

RESUMEN

Cell permeabilization by electric pulses (EPs), or electroporation, has been well established as a tool to indiscriminately increase membrane flows of water solutes down the concentration and voltage gradients. However, we found that EPs of nanosecond duration (nsEPs) trigger formation of voltage-sensitive and inward-rectifying membrane pores. NsEP-treated cells remain mostly impermeable to propidium, suggesting that the maximum pore size is approximately 1nm. The ion-channel-like properties of nsEP-opened nanopores vanish if they break into larger, propidium-permeable "conventional" pores. However, nanopores can be stable for many minutes and significantly impact cell electrolyte and water balance. Multiple nsEPs cause fast cell swelling and blebbing, whereas opening of larger pores with digitonin abolishes swelling and causes blebs to implode. The lipid nature of nsEP-opened nanopores is confirmed by fast externalization of phosphatidylserine residues. Nanopores constitute a previously unexplored ion transport pathway that supplements classic ion channels but is distinctly different from them.


Asunto(s)
Permeabilidad de la Membrana Celular , Membrana Celular/química , Electroporación , Lípidos de la Membrana/química , Animales , Membrana Celular/metabolismo , Cricetinae , Canales Iónicos/química , Canales Iónicos/metabolismo , Membrana Dobles de Lípidos/química , Membrana Dobles de Lípidos/metabolismo , Lípidos de la Membrana/metabolismo , Ratones , Porosidad , Equilibrio Hidroelectrolítico
17.
Clin Cancer Res ; 14(10): 3105-12, 2008 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-18483378

RESUMEN

PURPOSE: Plitidepsin, given as a 1-hour weekly i.v. infusion for 3 consecutive weeks during a 4-week treatment cycle, was investigated in patients with solid tumors to determine the maximum tolerated dose and the recommended dose (RD) using this administration schedule. EXPERIMENTAL DESIGN: Consecutive cohorts of patients with metastatic solid tumors or non-Hodgkin's lymphomas were to be treated at escalating doses of plitidepsin in a conventional phase I study including pharmacokinetic analyses of plitidepsin in plasma, whole blood, and blood cell pellets. RESULTS: Forty-nine patients with solid tumors were enrolled, and 48 were treated with plitidepsin (doses from 0.133 to 3.6 mg/m2/week). Dose-limiting toxicities (defining 3.6 mg/m2/week as the maximum tolerated dose) included myalgia, increased creatine phosphokinase levels, and sustained grade 3/4 increases of hepatic enzyme levels. The RD was established at 3.2 mg/m2/week. The most common toxicities were fatigue, vomiting/nausea, anorexia, injection site reaction, and pain, mostly of mild or moderate severity. Muscular toxicity manifested by mild-moderate myalgia, weakness, and/or creatine phosphokinase elevations occurred in approximately 25% of patients and seemed to be dose related. Transient transaminase elevations were frequent but achieved grade 3 or 4 in only approximately 10% of patients. Plitidepsin lacked significant hematologic toxicity. No complete or partial tumor responses were observed; however, five patients had disease stabilization (including one patient with medullary thyroid carcinoma with an unconfirmed partial response and one patient with renal carcinoma with major tumor shrinkage in lung metastases). Pharmacokinetic results for the RD indicated a long plasma half-life give value (16.8 +/- 7.7 hour) and a high volume of distribution value (525.2 +/- 219.3 L). CONCLUSIONS: The recommended dose for plitidepsin given as a weekly 1-hour schedule was 3.2 mg/m2/week. Muscular and liver toxicity were dose limiting at 3.6 mg/m2/week. Additional evaluation of this dose dense schedule is warranted.


Asunto(s)
Antineoplásicos/administración & dosificación , Antineoplásicos/farmacocinética , Depsipéptidos/administración & dosificación , Depsipéptidos/farmacocinética , Neoplasias/tratamiento farmacológico , Adulto , Anciano , Antineoplásicos/efectos adversos , Depsipéptidos/efectos adversos , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Infusiones Intravenosas , Masculino , Dosis Máxima Tolerada , Persona de Mediana Edad , Neoplasias/sangre , Péptidos Cíclicos
18.
J Histochem Cytochem ; 56(2): 183-91, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17998566

RESUMEN

The Reg-related protein family member INGAP (islet neogenesis-associated protein) is a pleiotropic factor enhancing islet neogenesis, neurite growth, beta-cell protection, and beta-cell function. Using an antibody to the N-termini of INGAP, we have identified that immunoreactivity to INGAP localized to the pancreatic endocrine cells in mouse. INGAP- and insulin-immunoreactive cells are mutually exclusive, with INGAP-immunoreactive cells being preserved after streptozotocin-mediated destruction of beta-cells. Glucagon- and INGAP-immunoreactive cells colocalize, although respective antigen expression occurs in different intracellular locations. These data suggest that INGAP-immunoreactive cells include alpha-cells; however, detection of single INGAP-immunoreactive/glucagon-negative cells indicates that this may not be exclusive. In addition to mouse, detection of islet endocrine cells that were INGAP immunoreactive/glucagon immunoreactive/insulin negative was also observed in islets from human, monkey, and rat. These findings reveal that INGAP and/or related group 3 Reg proteins have a conserved expression in the pancreatic islet.


Asunto(s)
Antígenos de Neoplasias/metabolismo , Biomarcadores de Tumor/metabolismo , Islotes Pancreáticos/metabolismo , Lectinas Tipo C/metabolismo , Proteínas/metabolismo , Animales , Reacciones Antígeno-Anticuerpo , Línea Celular , Reacciones Cruzadas , Diabetes Mellitus Experimental/metabolismo , Glucagón/metabolismo , Células Secretoras de Glucagón/metabolismo , Haplorrinos , Humanos , Inmunohistoquímica , Insulina/metabolismo , Espacio Intracelular/metabolismo , Masculino , Ratones , Proteínas Asociadas a Pancreatitis , Transporte de Proteínas , Ratas , Proteínas Recombinantes/metabolismo , Especificidad de la Especie
19.
J Natl Cancer Inst ; 110(8): 871-879, 2018 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-29425304

RESUMEN

Background: Adjuvant therapies can prevent/delay bone metastasis development in breast cancer. We investigated whether serum bone turnover markers in early disease have clinical utility in identifying patients with a high risk of developing bone metastasis. Methods: Markers of bone formation (N-terminal propeptide of type-1 collagen [P1NP]) and bone resorption (C-telopeptide of type-1 collagen [CTX], pyridinoline cross-linked carboxy-terminal telopeptide of type-1 collagen [1-CTP]) were measured in baseline (pretreatment blood samples from 872 patients from a large randomized trial of adjuvant zoledronic acid (AZURE-ISRCTN79831382) in early breast cancer. Cox proportional hazards regression and cumulative incidence functions (adjusted for factors having a statistically significant effect on outcome) were used to investigate prognostic and predictive associations between recurrence events, bone marker levels, and clinical variables. All statistical tests were two-sided. Results: When considered as continuous variables (log transformed), P1NP, CTX, and 1-CTP were each prognostic for future bone recurrence at any time (P = .006, P = .009, P = .008, respectively). Harrell's c-indices were a P1NP of 0.57 (95% confidence interval [CI] = 0.51 to 0.63), CTX of 0.57 (95% CI = 0.51 to 0.62), and 1-CTP of 0.57 (95% CI = 0.52 to 0.63). In categorical analyses based on the normal range, high baseline P1NP (>70 ng/mL) and CTX (>0.299 ng/mL), but not 1-CTP (>4.2 ng/mL), were also prognostic for future bone recurrence (P = .03, P = .03, P = .10, respectively). None of the markers were prognostic for overall distant recurrence; that is, they were bone metastasis specific, and none of the markers were predictive of treatment benefit from zoledronic acid. Conclusions: Serum P1NP, CTX, and 1-CTP are clinically useful, easily measured markers that show good prognostic ability (though low-to-moderate discrimination) for bone-specific recurrence and are worthy of further study.


Asunto(s)
Biomarcadores de Tumor/sangre , Neoplasias Óseas/diagnóstico , Neoplasias Óseas/secundario , Huesos/metabolismo , Neoplasias de la Mama/sangre , Neoplasias de la Mama/patología , Desarrollo Óseo , Neoplasias Óseas/sangre , Neoplasias Óseas/prevención & control , Remodelación Ósea , Neoplasias de la Mama/tratamiento farmacológico , Quimioterapia Adyuvante/normas , Progresión de la Enfermedad , Detección Precoz del Cáncer/métodos , Femenino , Humanos , Infusiones Intravenosas , Persona de Mediana Edad , Pronóstico , Nivel de Atención , Reino Unido , Ácido Zoledrónico/administración & dosificación
20.
J Endocrinol ; 190(3): 729-37, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17003274

RESUMEN

Islet neogenesis associated protein (INGAP) is a protein factor that can stimulate new islet mass from adult pancreatic progenitor cells. In models of islet neogenesis, INGAP expression is elevated in pancreatic acinar cells. Using a transgenic model to drive a sustained expression of INGAP in pancreatic acinar cells, we have identified a protection to chemical-induced hyperglycemia. A sustained expression of INGAP during development did not perturb islet development or basal blood glucose homeostasis, although beta-cell mass and pancreatic insulin content were significantly increased in the INGAP transgenic mice. When challenged with a diabetogenic dose of streptozotocin (STZ), mice carrying the INGAP transgene did not become hyperglycemic. In contrast, wild-type mice became and remained hyperglycemic, blood glucose > 550 mg/dl. The serum insulin levels and islet morphology were preserved in the transgenic mice after STZ treatment. These data suggest that the sustained expression of INGAP in the acinar pancreas confers resistance to a diabetogenic insult. The INGAP transgenic mouse provides a new model to uncover factors that are protective to diabetes onset and biomarkers to track beta-cell pathology.


Asunto(s)
Diabetes Mellitus Experimental , Células Secretoras de Insulina/metabolismo , Proteínas/metabolismo , Animales , Diabetes Mellitus Experimental/prevención & control , Expresión Génica , Inmunidad Innata , Inmunohistoquímica/métodos , Hibridación in Situ/métodos , Insulina/análisis , Insulina/sangre , Células Secretoras de Insulina/química , Células Secretoras de Insulina/citología , Ratones , Ratones Transgénicos , Modelos Animales , Elastasa Pancreática/genética , Elastasa Pancreática/metabolismo , Proteínas Asociadas a Pancreatitis , Proteínas/genética
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