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1.
Redox Biol ; 68: 102957, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37977043

RESUMO

Progressive respiratory failure is the primary cause of death in the coronavirus disease 2019 (COVID-19) pandemic. It is the final outcome of the acute respiratory distress syndrome (ARDS), characterized by an initial exacerbated inflammatory response, metabolic derangement and ultimate tissue scarring. A positive balance of cellular energy may result crucial for the recovery of clinical COVID-19. Hence, we asked if two key pathways involved in cellular energy generation, AMP-activated protein kinase (AMPK)/acetyl-CoA carboxylase (ACC) signaling and fatty acid oxidation (FAO) could be beneficial. We tested the drugs metformin (AMPK activator) and baicalin (CPT1A activator) in different experimental models mimicking COVID-19 associated inflammation in lung and kidney. We also studied two different cohorts of COVID-19 patients that had been previously treated with metformin. These drugs ameliorated lung damage in an ARDS animal model, while activation of AMPK/ACC signaling increased mitochondrial function and decreased TGF-ß-induced fibrosis, apoptosis and inflammation markers in lung epithelial cells. Similar results were observed with two indole derivatives, IND6 and IND8 with AMPK activating capacity. Consistently, a reduced time of hospitalization and need of intensive care was observed in COVID-19 patients previously exposed to metformin. Baicalin also mitigated the activation of pro-inflammatory bone marrow-derived macrophages (BMDMs) and reduced kidney fibrosis in two animal models of kidney injury, another key target of COVID-19. In human epithelial lung and kidney cells, both drugs improved mitochondrial function and prevented TGF-ß-induced renal epithelial cell dedifferentiation. Our results support that favoring cellular energy production through enhanced FAO may prove useful in the prevention of COVID-19-induced lung and renal damage.


Assuntos
COVID-19 , Metformina , Síndrome do Desconforto Respiratório , Animais , Humanos , Metformina/farmacologia , Metformina/uso terapêutico , Proteínas Quinases Ativadas por AMP/metabolismo , Rim/metabolismo , Pulmão/metabolismo , Inflamação/tratamento farmacológico , Fator de Crescimento Transformador beta , Fibrose , Ácidos Graxos
2.
Life Sci Alliance ; 6(10)2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37487638

RESUMO

Tubulointerstitial fibrosis is the common pathological substrate for many etiologies leading to chronic kidney disease. Although perturbations in the circadian rhythm have been associated with renal disease, the role of the molecular clock in the pathogenesis of fibrosis remains incompletely understood. We investigated the relationship between the molecular clock and renal damage in experimental models of injury and fibrosis (unilateral ureteral obstruction, folic acid, and adenine nephrotoxicity), using genetically modified mice with selective deficiencies of the clock components Bmal1, Clock, and Cry We found that the molecular clock pathway was enriched in damaged tubular epithelial cells with marked metabolic alterations. In human tubular epithelial cells, TGFß significantly altered the expression of clock components. Although Clock played a role in the macrophage-mediated inflammatory response, the combined absence of Cry1 and Cry2 was critical for the recruitment of neutrophils, correlating with a worsening of fibrosis and with a major shift in the expression of metabolism-related genes. These results support that renal damage disrupts the kidney peripheral molecular clock, which in turn promotes metabolic derangement linked to inflammatory and fibrotic responses.


Assuntos
Adenina , Rim , Humanos , Animais , Camundongos , Ritmo Circadiano , Células Epiteliais , Macrófagos
5.
Fam Med ; 54(8): 629-633, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36098694

RESUMO

BACKGROUND AND OBJECTIVES: Primary care physician shortage represents a challenge for many countries and territories, including Puerto Rico (PR), where a significant proportion of the graduating medical students preferred the continental United States (C-US) to complete their training and even as the definitive setting for their practice. We surveyed medical students who graduated from medical schools in PR and have been accepted in a residency program to evaluate the influence of a set of demographics, academic, and personal factors in their decision to pursue a primary care residency program in the C-US. METHODS: A 19-item questionnaire was distributed by institutional email to those medical students who graduated from one of the four Liaison Committee on Medical Education fully accredited medical schools in PR in 2019. We summarized our data by frequency and percentages. We performed data analysis with statistical significance considered for P values <.05. RESULTS: The questionnaire had a response rate of 51% (138/273), where 49% (67/138) were accepted in a primary care residency. Sixty percent (40/67) matched in a primary care program in the C-US. Among the evaluated factors, a prior degree in C-US (65%) and first-degree relatives living in the C-US (70%) were associated with students who matched in the mainland. First-degree relatives living in PR (96%) were associated with students who remained on the island for training. CONCLUSIONS: The results provide insight into the influence that personal factors have on the decision of medical students in PR to pursue primary care training in the C-US.


Assuntos
Internato e Residência , Estudantes de Medicina , Humanos , Atenção Primária à Saúde , Porto Rico , Faculdades de Medicina , Estados Unidos
6.
iScience ; 25(8): 104751, 2022 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-35942101

RESUMO

Differences in ciliary morphology and dynamics among multiciliated cells of the respiratory tract contribute to efficient mucociliary clearance. Nevertheless, little is known about how these phenotypic differences are established. We show that Prominin 1 (Prom1), a transmembrane protein widely used as stem cell marker, is crucial to this process. During airway differentiation, Prom1 becomes restricted to multiciliated cells, where it is expressed at distinct levels along the proximal-distal axis of the airways. Prom1 is induced by Notch in multiciliated cells, and Notch inactivation abolishes this gradient of expression. Prom1 was not required for multicilia formation, but when inactivated resulted in longer cilia that beat at a lower frequency. Disruption of Notch resulted in opposite effects and suggested that Notch fine-tunes Prom1 levels to regulate the multiciliated cell phenotype and generate diversity among these cells. This mechanism could contribute to the innate defense of the lung and help prevent pulmonary disease.

7.
Nucleic Acids Res ; 50(14): 8207-8225, 2022 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-35848924

RESUMO

RNA-binding proteins (RBPs) have been relatively overlooked in cancer research despite their contribution to virtually every cancer hallmark. Here, we use RNA interactome capture (RIC) to characterize the melanoma RBPome and uncover novel RBPs involved in melanoma progression. Comparison of RIC profiles of a non-tumoral versus a metastatic cell line revealed prevalent changes in RNA-binding capacities that were not associated with changes in RBP levels. Extensive functional validation of a selected group of 24 RBPs using five different in vitro assays unveiled unanticipated roles of RBPs in melanoma malignancy. As proof-of-principle we focused on PDIA6, an ER-lumen chaperone that displayed a novel RNA-binding activity. We show that PDIA6 is involved in metastatic progression, map its RNA-binding domain, and find that RNA binding is required for PDIA6 tumorigenic properties. These results exemplify how RIC technologies can be harnessed to uncover novel vulnerabilities of cancer cells.


Assuntos
Melanoma , Metástase Neoplásica , Isomerases de Dissulfetos de Proteínas , Proteínas de Ligação a RNA , Linhagem Celular Tumoral , Retículo Endoplasmático , Humanos , Melanoma/genética , Melanoma/patologia , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Metástase Neoplásica/genética , Isomerases de Dissulfetos de Proteínas/genética , Isomerases de Dissulfetos de Proteínas/metabolismo , RNA/genética , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo
8.
J Cosmet Dermatol ; 21(7): 2939-2944, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34766699

RESUMO

BACKGROUND: Pliaglis® is a self-occluding topical anesthetic containing a eutectic mixture of 7% lidocaine and 7% tetracaine, with proven efficacy and safety in several trials. AIMS: To evaluate the effectiveness and safety of Pliaglis® for different dermatological procedures in real-life clinical practice. METHODS: This retrospective, multicenter study included 35 patients treated with Pliaglis® prior to five dermatological procedures (pulsed dyed laser, picosecond laser, non-ablative fractional laser, radiofrequency microneedling, and photodynamic therapy). The primary endpoint was to assess the pain during the procedure with a visual analogue score (VAS) from 0 (no pain) to 10 (most severe pain). Secondary endpoints were the global effectiveness and tolerability (from 0 = very low to 10 = excellent), and the adverse events (AEs) after Pliaglis® removal, classified according to intensity (1-3). RESULTS: The median and mean pain VAS reported by patients was 2 (range 0-9) and 2.9 (±2.3), respectively. More than 65% of the patients had a VAS score ≤3. The effectiveness reported by investigators was "very good" (median 8 [range 2-10], mean 7.5 [±1.9]), which was strongly correlated with the pain VAS reported by patients (Spearman coefficient = - 0.9; p < 0.001). Forty-five percent of patients reported AEs and they were transient and mostly mild, with a mean intensity score of 1.5 (range 1-3). Tolerability of Pliaglis® was reported by investigators as "excellent" (median 10 [range 1-10], mean 9 [±1.8]). CONCLUSIONS: Pliaglis® is an effective topical anesthetic for several dermatological procedures, with an excellent safety and tolerability profile.


Assuntos
Anestésicos Locais , Tetracaína , Administração Tópica , Anestésicos Locais/efeitos adversos , Método Duplo-Cego , Humanos , Lidocaína/efeitos adversos , Dor/induzido quimicamente , Medição da Dor , Estudos Retrospectivos , Tetracaína/efeitos adversos
9.
PeerJ ; 9: e11891, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34430082

RESUMO

Intraoperative identification of parathyroid glands is a tough task for surgeons performing thyroid or parathyroid surgery, because the small size, color and shape of these glands hinder their discrimination from other cervical tissues. In 2011, Paras described the autofluorescence of parathyroid glands, a property that could facilitate their intraoperative identification. Parathyroid glands submitted to a 785 nm laser beam emit fluorescence in the near infrared range, with a peak at 822 nm. As the intrinsic properties of secretory tissues may be affected by the exposure to the near infrared light, a situation that could preclude their intraoperative utilization, the authors compared the structural and ultra-structural patterns of rat's thyroid and parathyroid glands submitted to irradiation replicating the conditions that allow their intraoperative identification, with those of non irradiated animals. Twenty-four Wistar rats were divided into six groups: animals of Groups 1, 3 and 5 were submitted under general anesthesia to direct irradiation of the cervical area with a 780 nm LED light for 3 minutes through a cervical incision, and animals of Groups 2, 4 and 6 were submitted to cervical dissection without irradiation. Animals of were euthanized immediately (Groups 1 and 2), at Day 30 (Groups 3 and 4) at and at Day 60 (Groups 5 and 6) and thyroid and parathyroid glands were removed: one lobe was prepared for conventional pathological examination and the other lobe for electron microscopy observed by three experienced pathological experts. Twenty-four samples were prepared for conventional histology and there were no alterations reported in any group. Due to technical problems, only 21 samples were observed by electron microscopy and there were no differences in the ultrastructure of parathyroid and thyroid glands, namely the nuclear pattern, mitochondria, endoplasmic reticulum or secretory granules, in any of the groups. These results confirm the innocuity of near infrared irradiation', allowing its intraoperative utilization.

10.
J Fluoresc ; 31(5): 1235-1239, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34283330

RESUMO

Intraoperative discrimination of thyroid and parathyroid tissues is fundamental in thyroid surgery. Recent fluorescence studies have shown stronger NIR emission in parathyroid tissue than in thyroid tissue, presenting a potential avenue for the development of a tool for surgical assistance. However, the fluorophore responsible for this emission has not yet been identified. In this work, spectroscopic analysis was performed to ascertain the origin of the emission peaks in parathyroid tissue. Ground-state diffuse reflectance (GSDR) absorption spectroscopy and laser-induced luminescence (LIL) emission spectroscopy were performed in parathyroid, thyroid, and fatty tissue samples and the resulting spectra were compared with the peaks of known fluorophores to identify the origin of each peak. The spectra of the different tissue types were also compared in order to evaluate the wavelength which presents the highest parathyroid emission relative to the emission of the surrounding tissues, representing the ideal wavelength for parathyroid detection. An emission peak in these conditions was observed for both thyroid and parathyroid tissue at 711 nm, with a higher intensity in parathyroid sample, making it suitable for detection applications. These results show a potential avenue for the development of a system allowing parathyroid detection in a surgical setting.


Assuntos
Glândulas Paratireoides , Glândula Tireoide , Fluorescência , Lasers
11.
Sci Rep ; 11(1): 15287, 2021 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-34315987

RESUMO

Heart failure (HF) and the development of chronic kidney disease (CKD) have a direct association. Both can be cause and consequence of the other. Many factors are known, such as diabetes or hypertension, which can lead to the appearance and/or development of these two conditions. However, it is suspected that other factors, namely genetic ones, may explain the differences in the manifestation and progression of HF and CKD among patients. One candidate factor is Rph, a gene expressed in the nervous and excretory system in mammals and Drosophila, encoding a Rab small GTPase family effector protein implicated in vesicular trafficking. We found that Rph is expressed in the Drosophila heart, and the silencing of Rph gene expression in this organ had a strong impact in the organization of fibers and functional cardiac parameters. Specifically, we observed a significant increase in diastolic and systolic diameters of the heart tube, which is a phenotype that resembles dilated cardiomyopathy in humans. Importantly, we also show that silencing of Rabphilin (Rph) expression exclusively in the pericardial nephrocytes, which are part of the flies' excretory system, brings about a non-cell-autonomous effect on the Drosophila cardiac system. In summary, in this work, we demonstrate the importance of Rph in the fly cardiac system and how silencing Rph expression in nephrocytes affects the Drosophila cardiac system.


Assuntos
Cardiomiopatia Dilatada/genética , Proteínas de Drosophila/genética , Inativação Gênica , Proteínas do Tecido Nervoso/genética , Animais
13.
Gland Surg ; 9(4): 893-898, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32953598

RESUMO

BACKGROUND: Incidental excision of parathyroid glands is a common event during thyroid surgery and in spite the divergent results that can be obtained from the literature about its clinical significance, all efforts must be used to their preservation. Due to the autofluorescence emitted by parathyroid glands, authors began to use a custom device to inspect thyroidectomy specimens for incidentally removed parathyroid tissue; the results of using this device are presented in this manuscript. METHODS: Specimens of 40 consecutive thyroid surgeries were inspected. Localization of suspect high-fluorescence spots were recorded for confirmation with a pathological exam. Determinations of calcium and parathyroid hormone (PTH) were completed prior to surgery and at 24 hours and 15 days after the operation. RESULTS: Patient age ranged from 36 to 83 years and were predominantly female (82.5%). Calcium values at 24 hours post-operation varied between 7.1 and 9.5. The PTH values ranged between 3 and 77. Thirteen patients (32.5%) presented with biochemical hypocalcemia at 24 hours. At 15 days after the operation, only one patient presented with a calcium value below 8 (PTH: 10.9) with complete normalization 6 months after the surgery. Pathological examination identified eight parathyroid fragments in seven patients. There was no correlation between the presence of parathyroid tissue in the specimen and post-operative hypocalcemia (P=0.254). Eight suspicious areas of augmented fluorescence where detected; seven were coincident with the pathological examination and one was a false positive. One intrathyroidal gland was not identified, resulting a sensitivity of 87.5% and specificity 96.2%. CONCLUSIONS: Although no correlation between incidental parathyroidectomy and hypocalcemia was demonstrated, autofluorescence may be a useful tool for in-table identification of incidentally-removed glands.

14.
J Surg Case Rep ; 2020(6): rjaa156, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32587681

RESUMO

Fibrous solitary tumors (FST) are mesenchymal tumors that can appear in different body regions. It is estimated that around 30% are found in the thoracic region, while rarely in meninges, abdomen, pelvis, extremities and bones. A correct diagnosis is important because 15-20% of cases develop a malignant behavior. Treatment of choice is surgical and posterior follow-up is essential. We present two atypical extrapleural FST cases, diagnosed in our center. Both were treated with surgery and in one case arterial embolization to reduce the bleeding risk was previously done.

15.
Lasers Med Sci ; 35(1): 107-114, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31062187

RESUMO

This study evaluates possible changes in weight and the secretory patterns of the thyroid and parathyroid glands irradiated with a 780-nm light-emitting diode (LED) source under conditions allowing their identification in an animal model. The use of near-infrared light sources to detect the parathyroid glands has been a subject of research due to the benefit provided to patients undergoing thyroid and parathyroid surgery. However, few studies have explored possible changes in weight and the secretory patterns of the glands when subjected to light stimulation. Thirty-two male Wistar rats were divided into two groups and subjected to cervical dissection and irradiation of the thyroid-parathyroid region under general anesthesia. The animals in group 1 (irradiated) were exposed to a 780-nm LED light beam for 180 s (dose 1.37 J/cm2), whereas the animals in group 2 (control) were not irradiated. Blood samples were collected pre-exposure, 7 min after exposure, and 30 and 60 days after exposure to measure calcium, parathyroid hormone (PTH), triiodothyronine (T3), thyroxine (T4), and thyroid-stimulating hormone (TSH) levels in both groups. Weight variations between the evaluation periods were also analyzed. Parametric statistics were used (Student's t test and ANOVA) after assuming normal distribution of continuous variables with the Shapiro-Wilk test. No significant variation was observed in any of the analyzed parameters pre- and postexposure. A significant increase in the calcium level was observed at 30 days in the irradiated group compared with that in the control group (11.156 ± 1.31 mg/dl vs 10.300 ± 0.30 mg/dl; df = 30 p < 0.03) but this change was no longer observed at 60 days (9.925 ± 0.23 mg/dl vs 10.014 ± 0.18 mg/dl; df = 14 p = 0.21). Irradiated rats gained less weight in the first 30 days after surgery (39.647 ± 32.39 vs 55.917 ± 22.61; df = 30 p = 0.146) and at 60 days (84.000 ± 27.36 vs 84.571 ± 5.62; df = 14 p = 0.957), no differences were observed between the two groups. No significant variations in weight development or changes in the secretory patterns of the thyroid and parathyroid glands exposed to near-infrared stimulation were observed, confirming the safety of this light source in the identification of the parathyroid glands.


Assuntos
Peso Corporal/efeitos da radiação , Raios Infravermelhos , Glândulas Paratireoides/metabolismo , Glândulas Paratireoides/efeitos da radiação , Glândula Tireoide/efeitos da radiação , Animais , Cálcio/metabolismo , Masculino , Ratos , Ratos Wistar , Glândula Tireoide/metabolismo , Hormônios Tireóideos/metabolismo , Fatores de Tempo
17.
Nutr Hosp ; 36(6): 1278-1287, 2019 Dec 26.
Artigo em Espanhol | MEDLINE | ID: mdl-31657604

RESUMO

INTRODUCTION: Background: the duodenal switch (DS) is a procedure that combines a vertical gastrectomy (VG) plus a biliopancreatic diversion (BPD). Objectives: to report our experience in 950 consecutive DS patients with morbid obesity (MO) performed from 1994 to 2011, with 27 years of follow-up. Environment: mix of teaching and private institution in a regional hospital in Spain. Methods: retrospective review of 950 consecutive morbidly obese patients treated with DS surgery. Results: five hundred and eighteen open DS (ODS) and 432 laparoscopic DS (LDS) were performed. Operative mortality was 0.84% (1.38% in ODS and 0.38% in LDS); 4.84% had one leak, two had liver failure (0.2%) and malnutrition was present in 3.1%. At five years, the body mass index (BMI) percentage of lost overweight (%EWL) was 80% and the percentage of expected BMI loss was more than 100%. Conclusions: the DS is the most aggressive bariatric technique but with the best long-term weight loss. Operative complications and long-term follow-up guidelines are described.


INTRODUCCIÓN: Antecedentes: el cruce duodenal (CD) es un procedimiento que combina una gastrectomía vertical (GV) más una derivación biliopancreática (DBP). Objetivos: informar de nuestra experiencia en 950 CD consecutivos en pacientes con obesidad mórbida (OM) realizados de 1994 a 2011 y con 27 años de seguimiento. Entorno: mezcla de enseñanza e institución privada en un hospital comarcal de España. Métodos: revisión retrospectiva de 950 pacientes consecutivos con obesidad mórbida tratados con cirugía de CD. Resultados: se realizaron 518 CD abiertos (CDA) y 432 CD laparoscópicos (CDL). La mortalidad operatoria fue del 0,84% (1,38% en CDA y 0,38% en CDL). El 4,84% tuvo una fuga, dos tuvieron insuficiencia hepática (0,2%) y la desnutrición estuvo presente en el 3,1%. A los cinco años, el porcentaje de sobrepeso perdido (PSP) de índice de masa corporal (IMC) fue del 80% y el porcentaje de pérdida esperada de IMC fue más del 100%. Conclusiones: el CD es la técnica bariátrica más agresiva pero con mejor pérdida de peso a largo plazo. Se describen las complicaciones operatorias y pautas de seguimiento a largo plazo.


Assuntos
Cirurgia Bariátrica/métodos , Desvio Biliopancreático/métodos , Duodeno/cirurgia , Gastrectomia/métodos , Obesidade Mórbida/cirurgia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Tempo , Adulto Jovem
18.
BMC Surg ; 19(1): 120, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31455299

RESUMO

BACKGROUND: Intra-operative identification of parathyroid glands is often a challenge for surgeons performing parathyroid or thyroid surgery. Parathyroid glands stimulated by near-infrared light emit autofluorescence, which allows their discrimination from all other tissues in the region, and this may be of value during thyroid and parathyroid surgery. In this study, we present the results of the utilization of a low-cost device developed for the identification of parathyroid glands in surgery for primary hyperparathyroidism. CASE PRESENTATION: In 5 patients operated in our hospital with the diagnosis of primary hyperparathyroidism and non-concordant ultrasonography and Sestamibi scan, we used a 780 nm Light Emitting Diode (LED) to stimulate the cervical area. The resulting autofluorescence was visualized with night vision goggles with a 832 nm filter assembled. In all the five patients, an easily distinguishable nodule was identified and excised, and confirmed as parathyroid adenoma by histological exam. Intra-operative PTH assay showed significant decrease compared with basal values, fulfilling the Miami Criteria for surgical success in use in our institution. CONCLUSION: The utilization of autofluorescence for intra-operative identification of parathyroid glands may have a clinical application in surgery for primary hyperparathyroidism, being of special utility when ultrasonography and Sestamibi Scan are non concordant.


Assuntos
Hiperparatireoidismo Primário/cirurgia , Glândulas Paratireoides/cirurgia , Neoplasias das Paratireoides/diagnóstico , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cintilografia , Tecnécio Tc 99m Sestamibi , Ultrassonografia
19.
J Cutan Pathol ; 46(4): 285-289, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30632185

RESUMO

BACKGROUND: The plaque variant of trichoblastoma has been described as a solitary tumor with diffuse infiltration of the lower dermis and hypodermis, with poorly defined borders. Herein, we report a new variant of multiple centrofacial trichoblastoma. OBJECT: To describe clinical and pathological features of a new multiple kind of plaque variant of centrofacial trichoblastoma. METHODS: Case series of patients with a multiple-plaque variant of centrofacial trichoblastoma treated in our department between 2005 and 2017. We identified eight patients with the centrofacial plaque variant of trichoblastoma treated in our department from 2005 to 2017. RESULTS: The final study sample comprised 13 trichoblastomas from four patients. All patients also developed at least one basal cell carcinoma. Mohs surgery was the method of treatment in the majority of the cases of trichoblastoma and in all the cases of basal cell carcinoma. We needed between 2 and 6 stages to obtain free margins in our cases of facial plaque trichoblastomas treated by Mohs surgery. CONCLUSION: To the best of our knowledge, a multiple-plaque variant of trichoblastoma has not been described in the literature. We suggest a genetic origin of this variant of trichoblastoma and describe its remarkable infiltrative nature, with poorly defined surgical margins.


Assuntos
Doenças do Cabelo/patologia , Folículo Piloso/patologia , Neoplasias Cutâneas/patologia , Idoso , Face/patologia , Feminino , Doenças do Cabelo/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Cirurgia de Mohs , Neoplasias Cutâneas/cirurgia
20.
Cell Stem Cell ; 23(4): 516-529.e5, 2018 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-30244870

RESUMO

Pluripotent stem cells (PSCs) could provide a powerful system to model development of the human esophagus, whose distinct tissue organization compared to rodent esophagus suggests that developmental mechanisms may not be conserved between species. We therefore established an efficient protocol for generating esophageal progenitor cells (EPCs) from human PSCs. We found that inhibition of TGF-ß and BMP signaling is required for sequential specification of EPCs, which can be further purified using cell-surface markers. These EPCs resemble their human fetal counterparts and can recapitulate normal development of esophageal stratified squamous epithelium during in vitro 3D cultures and in vivo. Importantly, combining hPSC differentiation strategies with mouse genetics elucidated a critical role for Notch signaling in the formation of this epithelium. These studies therefore not only provide an efficient approach to generate EPCs, but also offer a model system to study the regulatory mechanisms underlying development of the human esophagus.


Assuntos
Esôfago/embriologia , Esôfago/metabolismo , Imageamento Tridimensional , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/metabolismo , Receptores Notch/metabolismo , Transdução de Sinais , Animais , Esôfago/citologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD
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