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1.
J Clin Med ; 13(7)2024 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-38610622

RESUMO

Background: Painful vaso-occlusive episodes (VOEs) are the hallmark of sickle cell disease (SCD) and account for frequent visits to the emergency department (ED) or urgent care (UC). Currently, the early administration of analgesics is recommended as initial management; however, there is a need for further understanding of the effect of prompt analgesics and hydration during VOEs. The objective of this study is to analyze the factors associated with the rate of hospital admission in the setting of time to intravenous (IV) analgesics and hydration. Method: This retrospective single-institution study reviewed adult and pediatric patients with SCD who presented with VOEs from January 2018 to August 2023. Results: Of 303 patient encounters, the rates of admission for the overall group, the subgroup which received IV hydration within 60 min of arrival, and the subgroup which received both IV analgesics and hydration within 60 min were 51.8%, 25.6% (RR = 0.46), and 18.2% (RR = 0.33), respectively. Further, factors such as gender and the use of hydroxyurea were found to be significantly associated with the rate of admission. Conclusions: This signifies the importance of standardizing the management of VOEs through the timely administration of IV analgesics and hydration in both adult and pediatric ED/UC.

2.
Ann Med Surg (Lond) ; 85(11): 5350-5354, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37915687

RESUMO

Background: The COVID-19 pandemic has caused an international healthcare crisis and produced a large healthcare burden. Diabetes mellitus (DM) is a common disease that can be controlled via pharmacologic agents; however, many patients have poor glycemic control, leading to disease-related complications. DM has been reported in the literature to be associated with increasing morbidity and mortality in COVID-19 patients. The authors aim to assess the associations between glucose homoeostasis and COVID-19 disease severity and mortality. Methods: A retrospective chart review of patients ages 18-100 years of age admitted with COVID-19 between January 2020 and December 2021 was performed. The primary outcome was COVID-19 mortality with respect to haemoglobin A1C levels of less than 5.7%, 5.7-6.4%, and 6.5% and greater. Disease severity was determined by degree of supplemental oxygen requirements (ambient air, low-flow nasal cannula, high-flow nasal cannula, non-invasive mechanical ventilation, and invasive mechanical ventilation). COVID-19 mortality and severity were also compared to blood glucose levels on admission as grouped by less than 200 mg/dl and greater than or equal to 200 mg/dl. Results: A total of 1156 patients were included in the final analysis. There was a statistically significant association between diabetic status and mortality (P=0.0002). Statistical significance was also noted between admission blood glucose ≥200 mg/dl and mortality (P=0.0058) and respiratory disease severity (P=0.0381). A multivariate logistic regression for predicting mortality showed increasing haemoglobin A1C was associated with increased mortality (odds ratio 1.72 with 95% CI of 1.122-2.635). Conclusions: In our 2-year retrospective analysis, there was an association between a diagnosis of DM and COVID-19-related mortality. Hyperglycaemia on admission was found to be statistically significant with mortality in patients diagnosed with COVID-19. Glucose homoeostasis and insulin dysregulation likely play a contributing factor to COVID-19 disease severity and mortality.

3.
Blood Res ; 58(3): 138-144, 2023 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-37751922

RESUMO

Background: Early reports have indicated a relationship between ABO and rhesus blood group types and infection with SARS-CoV-2. We aim to examine blood group type associations with COVID-19 mortality and disease severity. Methods: This is a retrospective chart review of patients ages 18 years or older admitted to the hospital with COVID-19 between January 2020 and December 2021. The primary outcome was COVID-19 mortality with respect to ABO blood group type. The secondary outcomes were 1. Severity of COVID-19 with respect to ABO blood group type, and 2. Rhesus factor association with COVID-19 mortality and disease severity. Disease severity was defined by degree of supplemental oxygen requirements (ambient air, low-flow, high-flow, non-invasive mechanical ventilation, and invasive mechanical ventilation). Results: The blood type was collected on 596 patients with more than half (54%, N=322) being O+. The ABO blood type alone was not statistically associated with mortality (P=0.405), while the RH blood type was statistically associated with mortality (P<0.001). There was statistically significant association between combined ABO and RH blood type and mortality (P=0.014). Out of the mortality group, the O+ group had the highest mortality (52.3%), followed by A+ (22.8%). The combined ABO and RH blood type was statistically significantly associated with degree of supplemental oxygen requirements (P=0.005). The Kaplan-Meier curve demonstrated that Rh- patients had increased mortality. Conclusion: ABO blood type is not associated with COVID-19 severity and mortality. Rhesus factor status is associated with COVID-19 severity and mortality. Rhesus negative patients were associated with increased mortality risk.

4.
Fed Pract ; 39(Suppl 1): S21-S25, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35765694

RESUMO

Background: Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) syndrome is the most common monogenic inherited cause of stroke. Case Presentation: A female patient aged > 50 years with genetically proven CADASIL syndrome and an extensive stroke/transient ischemic attack (TIA) history experienced a bradycardic episode following hospitalization for new strokelike symptoms. The literature of cardiac involvement in CADASIL syndrome is limited, with no definitive recommendations for surveillance and screening. Conclusions: This case report postulates that cardiac surveillance and screening may be indicated for patients with CADASIL syndrome.

5.
Cureus ; 14(2): e22326, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35371663

RESUMO

Proton-pump inhibitors (PPIs) are commonly utilized in the treatment of upper gastrointestinal bleeds (UGIBs) due to their ability to stabilize blood clot formation. PPIs have been shown to reduce rebleeding after endoscopic hemostasis and reduce signs of bleeding at index endoscopy. While PPIs are well-tolerated and commonly administered to patients suffering from acute UGIBs, significant adverse effects may occur. Patients have reported various mild systemic symptoms during short-term PPI use, including headache, rash, dizziness, nausea, abdominal pain, flatulence, constipation, and diarrhea. In general, serious side effects of PPIs tend to be mild during treatment periods under two weeks; however, as the treatment duration increases, side effects have been observed to increase in frequency and severity. PPI-induced thrombocytopenia is an exceedingly rarely reported adverse reaction that remains largely unstudied due to the dearth of patient cases. This adverse effect continues to be a diagnosis of exclusion, and there are no current evidence-based recommendations to approach this complication. Thrombocytopenia increases the risk of rebleeding and hemodynamic instability, which may be devastating to patients suffering from UGIBs. Here, we present a case of thrombocytopenia that began after the introduction of pantoprazole in the setting of a UGIB. The thrombocytopenia resolved promptly after cessation of the medication. We highlight this case to increase awareness of this rare finding given the lack of recommendations for short-term PPI-induced thrombocytopenia.

6.
Blood ; 137(7): 945-958, 2021 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-33254233

RESUMO

Isocitrate dehydrogenase (IDH) mutations are common genetic alterations in myeloid disorders, including acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS). Epigenetic changes, including abnormal histone and DNA methylation, have been implicated in the pathogenic build-up of hematopoietic progenitors, but it is still unclear whether and how IDH mutations themselves affect hematopoiesis. Here, we show that IDH1-mutant mice develop myeloid dysplasia in that these animals exhibit anemia, ineffective erythropoiesis, and increased immature progenitors and erythroblasts. In erythroid cells of these mice, D-2-hydroxyglutarate, an aberrant metabolite produced by the mutant IDH1 enzyme, inhibits oxoglutarate dehydrogenase activity and diminishes succinyl-coenzyme A (CoA) production. This succinyl-CoA deficiency attenuates heme biosynthesis in IDH1-mutant hematopoietic cells, thus blocking erythroid differentiation at the late erythroblast stage and the erythroid commitment of hematopoietic stem cells, while the exogenous succinyl-CoA or 5-ALA rescues erythropoiesis in IDH1-mutant erythroid cells. Heme deficiency also impairs heme oxygenase-1 expression, which reduces levels of important heme catabolites such as biliverdin and bilirubin. These deficits result in accumulation of excessive reactive oxygen species that induce the cell death of IDH1-mutant erythroid cells. Our results clearly show the essential role of IDH1 in normal erythropoiesis and describe how its mutation leads to myeloid disorders. These data thus have important implications for the devising of new treatments for IDH-mutant tumors.


Assuntos
Eritropoese/genética , Células-Tronco Hematopoéticas/metabolismo , Heme/biossíntese , Isocitrato Desidrogenase/genética , Mutação de Sentido Incorreto , Mutação Puntual , Pré-Leucemia/genética , Acil Coenzima A/biossíntese , Acil Coenzima A/deficiência , Anemia/genética , Animais , Medula Óssea/patologia , Eritroblastos/metabolismo , Técnicas de Introdução de Genes , Glutaratos/metabolismo , Heme/deficiência , Heme Oxigenase-1/metabolismo , Isocitrato Desidrogenase/fisiologia , Complexo Cetoglutarato Desidrogenase/antagonistas & inibidores , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Células Mieloides/patologia , Mielopoese/genética , Pré-Leucemia/metabolismo , Pré-Leucemia/patologia , Espécies Reativas de Oxigênio/metabolismo , Proteínas Recombinantes/metabolismo , Esplenomegalia/etiologia , Trombocitopenia/genética
7.
Haematologica ; 105(10): 2407-2419, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-33054081

RESUMO

Adherent neutrophils on vascular endothelium positively contribute to cell-cell aggregation and vaso-occlusion in sickle cell disease. In the present study, we demonstrated that pyridoxamine, a derivative of vitamin B6, might be a therapeutic agent to alleviate intravascular cell-cell aggregation in sickle cell disease. Using real-time intravital microscopy, we found that one oral administration of pyridoxamine dose-dependently increased the rolling influx of neutrophils and reduced neutrophil adhesion to endothelial cells in cremaster microvessels of sickle cell disease mice challenged with hypoxia-reoxygenation. Short-term treatment also mitigated neutrophil-endothelial cell and neutrophil-platelet interactions in the microvessels and improved the survival of sickle cell disease mice challenged with tumor necrosis factor-α. The inhibitory effects of pyridoxamine on intravascular cell-cell interactions were potentiated by co-treatment with hydroxyurea. We observed that long-term (5.5 months) oral treatment with pyridoxamine significantly diminished the adhesive function of neutrophils and platelets and down-regulated the expression of E-selectin and intercellular adhesion molecule-1 on the vascular endothelium in tumor necrosis factor-α-challenged sickle cell disease mice. Ex vivo studies revealed that the surface amount of αMß2 integrin was significantly decreased in stimulated neutrophils isolated from sickle cell disease mice treated with pyridoxamine-containing water. Studies using platelets and neutrophils from sickle cell disease mice and patients suggested that treatment with pyridoxamine reduced the activation state of platelets and neutrophils. These results suggest that pyridoxamine may be a novel therapeutic and a supplement to hydroxyurea to prevent and treat vaco-occlusion events in sickle cell disease.


Assuntos
Anemia Falciforme , Piridoxamina , Anemia Falciforme/tratamento farmacológico , Animais , Adesão Celular , Comunicação Celular , Células Endoteliais , Endotélio Vascular , Humanos , Hidroxiureia , Camundongos , Neutrófilos
8.
Front Med (Lausanne) ; 5: 134, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29780806

RESUMO

Interactions of neutrophils with endothelial cells (ECs) and platelets contribute to tissue damage and vascular occlusion under sterile inflammatory conditions. However, the molecular mechanisms regulating the cell-cell interactions remain poorly understood. Previous studies suggest that reactive oxygen species, such as hydrogen peroxide (H2O2), produced from NADPH oxidase 2 play a critical role in platelet-neutrophil interactions by regulating the function of neutrophil αMß2 integrin during sterile inflammation. In this study, we further demonstrate a crucial role for myeloperoxidase (MPO) in regulating the adhesive function of neutrophils through αMß2 integrin. Using real-time fluorescence intravital microscopy and in vitro assays, we showed that loss of MPO promoted neutrophil-EC interactions and neutrophil emigration but did not affect neutrophil-platelet interactions under inflammatory conditions. Using genetic and pharmacologic approaches, we found that following agonist stimulation, MPO knockout (KO) neutrophils exhibited a significant increase in extracellular H2O2 and surface level of αMß2 integrin and that these effects were dependent on MPO activity. Our in vivo studies using an ischemia/reperfusion-induced hepatic inflammation model revealed that compared to wild-type mice, neutrophils from MPO KO mice-displayed a pro-migratory phenotype while ameliorating tissue damage. These results suggest that MPO plays a negative role in the adhesive and migratory function of neutrophils by impairing αMß2 integrin function under sterile inflammatory conditions.

9.
Blood ; 129(2): 209-225, 2017 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-27903531

RESUMO

Downstream regulatory element antagonist modulator (DREAM), a transcriptional repressor, is known to modulate pain responses. However, it is unknown whether DREAM is expressed in anucleate platelets and plays a role in thrombogenesis. By using intravital microscopy with DREAM-null mice and their bone marrow chimeras, we demonstrated that both hematopoietic and nonhematopoietic cell DREAMs are required for platelet thrombus formation following laser-induced arteriolar injury. In a FeCl3-induced thrombosis model, we found that compared with wild-type (WT) control and nonhematopoietic DREAM knockout (KO) mice, DREAM KO control and hematopoietic DREAM KO mice showed a significant delay in time to occlusion. Tail bleeding time was prolonged in DREAM KO control mice, but not in WT or DREAM bone marrow chimeric mice. In vivo adoptive transfer experiments further indicated the importance of platelet DREAM in thrombogenesis. We found that DREAM deletion does not alter the ultrastructural features of platelets but significantly impairs platelet aggregation and adenosine triphosphate secretion induced by numerous agonists (collagen-related peptide, adenosine 5'-diphosphate, A23187, thrombin, or U46619). Biochemical studies revealed that platelet DREAM positively regulates phosphoinositide 3-kinase (PI3K) activity during platelet activation. Using DREAM-null platelets and PI3K isoform-specific inhibitors, we observed that platelet DREAM is important for α-granule secretion, Ca2+ mobilization, and aggregation through PI3K class Iß (PI3K-Iß). Genetic and pharmacological studies in human megakaryoblastic MEG-01 cells showed that DREAM is important for A23187-induced Ca2+ mobilization and its regulatory function requires Ca2+ binding and PI3K-Iß activation. These results suggest that platelet DREAM regulates PI3K-Iß activity and plays an important role during thrombus formation.


Assuntos
Proteínas Interatuantes com Canais de Kv/metabolismo , Ativação Plaquetária/fisiologia , Proteínas Repressoras/metabolismo , Trombose/metabolismo , Animais , Plaquetas/metabolismo , Modelos Animais de Doenças , Citometria de Fluxo , Humanos , Immunoblotting , Imunoprecipitação , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Reação em Cadeia da Polimerase , Transdução de Sinais/fisiologia
10.
Haematologica ; 102(2): 246-259, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27758820

RESUMO

Previous studies identified the Ser/Thr protein kinase, AKT, as a therapeutic target in thrombo-inflammatory diseases. Here we report that specific inhibition of AKT with ARQ 092, an orally-available AKT inhibitor currently in phase Ib clinical trials as an anti-cancer drug, attenuates the adhesive function of neutrophils and platelets from sickle cell disease patients in vitro and cell-cell interactions in a mouse model of sickle cell disease. Studies using neutrophils and platelets isolated from sickle cell disease patients revealed that treatment with 50-500 nM ARQ 092 significantly blocks αMß2 integrin function in neutrophils and reduces P-selectin exposure and glycoprotein Ib/IX/V-mediated agglutination in platelets. Treatment of isolated platelets and neutrophils with ARQ 092 inhibited heterotypic cell-cell aggregation under shear conditions. Intravital microscopic studies demonstrated that short-term oral administration of ARQ 092 or hydroxyurea, a major therapy for sickle cell disease, diminishes heterotypic cell-cell interactions in venules of sickle cell disease mice challenged with tumor necrosis factor-α. Co-administration of hydroxyurea and ARQ 092 further reduced the adhesive function of neutrophils in venules and neutrophil transmigration into alveoli, inhibited expression of E-selectin and intercellular adhesion molecule-1 in cremaster vessels, and improved survival in these mice. Ex vivo studies in sickle cell disease mice suggested that co-administration of hydroxyurea and ARQ 092 efficiently blocks neutrophil and platelet activation and that the beneficial effect of hydroxyurea results from nitric oxide production. Our results provide important evidence that ARQ 092 could be a novel drug for the prevention and treatment of acute vaso-occlusive complications in patients with sickle cell disease.


Assuntos
Aminopiridinas/uso terapêutico , Anemia Falciforme/tratamento farmacológico , Anemia Falciforme/metabolismo , Plaquetas/metabolismo , Comunicação Celular/efeitos dos fármacos , Imidazóis/uso terapêutico , Neutrófilos/metabolismo , Inibidores de Proteínas Quinases/uso terapêutico , Administração Oral , Adulto , Aminopiridinas/farmacologia , Anemia Falciforme/genética , Anemia Falciforme/mortalidade , Animais , Biomarcadores , Adesão Celular/efeitos dos fármacos , Modelos Animais de Doenças , Feminino , Humanos , Hidroxiureia/farmacologia , Hidroxiureia/uso terapêutico , Imidazóis/farmacologia , Masculino , Camundongos Knockout , Pessoa de Meia-Idade , Ativação de Neutrófilo/efeitos dos fármacos , Ativação de Neutrófilo/imunologia , Neutrófilos/imunologia , Óxido Nítrico/metabolismo , Oxirredução/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Ativação Plaquetária/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , Migração Transendotelial e Transepitelial/efeitos dos fármacos , Migração Transendotelial e Transepitelial/imunologia , Resultado do Tratamento , Fator de Necrose Tumoral alfa/metabolismo , Adulto Jovem
11.
Cancer Cell ; 30(2): 337-348, 2016 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-27424808

RESUMO

Mutations in the isocitrate dehydrogenase-1 gene (IDH1) are common drivers of acute myeloid leukemia (AML) but their mechanism is not fully understood. It is thought that IDH1 mutants act by inhibiting TET2 to alter DNA methylation, but there are significant unexplained clinical differences between IDH1- and TET2-mutant diseases. We have discovered that mice expressing endogenous mutant IDH1 have reduced numbers of hematopoietic stem cells (HSCs), in contrast to Tet2 knockout (TET2-KO) mice. Mutant IDH1 downregulates the DNA damage (DD) sensor ATM by altering histone methylation, leading to impaired DNA repair, increased sensitivity to DD, and reduced HSC self-renewal, independent of TET2. ATM expression is also decreased in human IDH1-mutated AML. These findings may have implications for treatment of IDH-mutant leukemia.


Assuntos
Proteínas Mutadas de Ataxia Telangiectasia/genética , Dano ao DNA , Reparo do DNA , Proteínas de Ligação a DNA/genética , Células-Tronco Hematopoéticas/enzimologia , Isocitrato Desidrogenase/genética , Proteínas Proto-Oncogênicas/genética , Animais , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Proteínas de Ligação a DNA/metabolismo , Dioxigenases , Regulação para Baixo , Células-Tronco Hematopoéticas/citologia , Humanos , Isocitrato Desidrogenase/metabolismo , Camundongos , Mutação , Proteínas Proto-Oncogênicas/metabolismo
12.
Artigo em Inglês | MEDLINE | ID: mdl-27051454

RESUMO

Purpose. A patient-assessor-blinded, randomized, sham-controlled crossover trial was performed to investigate the effectiveness of laser acupuncture on anthropometric measurements and appetite sensation in obese subjects. Methods. Fifty-two obese subjects were randomly assigned to either the laser acupuncture group or the sham laser acupuncture group. Subjects within each group received the relevant treatment three times a week for 8 weeks. After a two-week washout period, the subjects then received the treatment of the opposite group for another 8 weeks. BMI, body fat percentage, waist-to-hip ratio (WHR), waist circumference, hip circumference, and appetite sensations were measured before and after 8 weeks of treatment. Results. BMI, body fat percentage, WHR, waist circumference, and hip circumference decreased significantly (p < 0.05) in the laser acupuncture group compared to baseline but there was no decrease in those variables in the sham laser acupuncture group. Laser acupuncture significantly improved scores on the fullness, hunger, satiety, desire to eat, and overall well-being relative to the baseline (p < 0.05). Conclusions. Laser acupuncture is well tolerated and improves anthropometric measurements and appetite sensations in obese subjects.

13.
Cell Oncol (Dordr) ; 39(3): 279-86, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26902080

RESUMO

BACKGROUND: Insulinomas are the most common type of neuroendocrine (NE) pancreatic islet tumors. Patients with insulinomas may develop complications associated with hyperinsulinemia. To increase the treatment options for insulinoma patients, we have tested a conditionally replicating adenovirus that has been engineered in such a way that it can specifically express therapeutic genes in NE tumors. METHODS: We used a promoter-specific adenoviral vector delivery system that is regulated by an INSM1 (insulinoma-associated-1) promoter, which is silent in normal adult tissues but active in developing NE cells and tumors. Through a series of modifications, using an insulator (HS4) and neuron-restrictive silencer elements (NRSEs), an oncolytic adenoviral vector was generated that retains tumor specificity and drives the expression of a mutated adenovirus E1A gene (Δ24E1A) and the herpes simplex virus thymidine kinase (HSV-tk) gene. The efficacy of this vector was tested in insulinoma-derived MIN, RIN, ßTC-1 and pancreatic (Panc-1) cells using in vitro cell survival and in vivo tumor growth assays. RESULTS: Using in vitro insulinoma-derived cell lines and an in vivo subcutaneous mouse tumor model we found that the INSM1 promoter-driven viruses were able to replicate specifically in INSM1-positive cells. INSM1-specific HSV-tk expression in combination with ganciclovir treatment resulted in dose-dependent tumor cell killing, leaving INSM1-negative cells unharmed. When we combined the INSM1-promoter driven HSV-tk with Δ24E1A and INSM1p-HSV-tk (K5) viruses, we found that the co-infected insulinoma-derived cells expressed higher levels of HSV-tk and exhibited more efficient tumor suppression than cells infected with INSM1p-HSV-tk virus alone. CONCLUSIONS: INSM1 promoter-driven conditionally replicating adenoviruses may serve as a new tool for the treatment of insulinoma and may provide clinicians with additional options to combat this disease.


Assuntos
Terapia Genética/métodos , Insulinoma , Terapia Viral Oncolítica/métodos , Neoplasias Pancreáticas , Regiões Promotoras Genéticas , Proteínas Repressoras/genética , Adenoviridae , Animais , Antineoplásicos/farmacologia , Western Blotting , Linhagem Celular Tumoral , Ganciclovir/farmacologia , Vetores Genéticos , Humanos , Camundongos , Timidina Quinase/genética , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Tissue Eng Part A ; 22(3-4): 197-207, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26529401

RESUMO

Advancement of engineered ear in clinical practice is limited by several challenges. The complex, largely unsupported, three-dimensional auricular neocartilage structure is difficult to maintain. Neocartilage formation is challenging in an immunocompetent host due to active inflammatory and immunological responses. The large number of autologous chondrogenic cells required for engineering an adult human-sized ear presents an additional challenge because primary chondrocytes rapidly dedifferentiate during in vitro culture. The objective of this study was to engineer a stable, human ear-shaped cartilage in an immunocompetent animal model using expanded chondrocytes. The impact of basic fibroblast growth factor (bFGF) supplementation on achieving clinically relevant expansion of primary sheep chondrocytes by in vitro culture was determined. Chondrocytes expanded in standard medium were either combined with cryopreserved, primary passage 0 chondrocytes at the time of scaffold seeding or used alone as control. Disk and human ear-shaped scaffolds were made from porous collagen; ear scaffolds had an embedded, supporting titanium wire framework. Autologous chondrocyte-seeded scaffolds were implanted subcutaneously in sheep after 2 weeks of in vitro incubation. The quality of the resulting neocartilage and its stability and retention of the original ear size and shape were evaluated at 6, 12, and 20 weeks postimplantation. Neocartilage produced from chondrocytes that were expanded in the presence of bFGF was superior, and its quality improved with increased implantation time. In addition to characteristic morphological cartilage features, its glycosaminoglycan content was high and marked elastin fiber formation was present. The overall shape of engineered ears was preserved at 20 weeks postimplantation, and the dimensional changes did not exceed 10%. The wire frame within the engineered ear was able to withstand mechanical forces during wound healing and neocartilage maturation and prevented shrinkage and distortion. This is the first demonstration of a stable, ear-shaped elastic cartilage engineered from auricular chondrocytes that underwent clinical-scale expansion in an immunocompetent animal over an extended period of time.


Assuntos
Condrócitos , Cartilagem da Orelha , Orelha , Engenharia Tecidual , Alicerces Teciduais/química , Animais , Células Cultivadas , Condrócitos/citologia , Condrócitos/metabolismo , Humanos , Ovinos
15.
Int J Oncol ; 48(1): 173-80, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26530405

RESUMO

Accurate detection of neuroendocrine (NE) tumors is critically important for better prognosis and treatment outcomes in patients. To demonstrate the efficacy of using an adenoviral vector for the detection of NE tumors, we have constructed a pair of adenoviral vectors which, in combination, can conditionally replicate and release Gaussia luciferase into the circulation after infecting the NE tumors. The expression of these two vectors is regulated upstream by an INSM1-promoter (insulinoma-associated-1) that is specifically active in NE tumors and developing NE tissues, but silenced in normal adult tissues. In order to retain the tumor-specificity of the INSM1 promoter, we have modified the promoter using the core insulator sequence from the chicken ß-globin HS4 insulator and the neuronal restrictive silencing element (NRSE). This modified INSM1-promoter can retain NE tumor specificity in an adenoviral construct while driving a mutated adenovirus E1A gene (∆24E1A), the Metridia, or Gaussia luciferase gene. The in vitro cell line and mouse xenograft human tumor studies revealed the NE specificity of the INSM1-promoter in NE lung cancer, neuroblastoma, medulloblastoma, retinoblastoma, and insulinoma. When we combined the INSM1-promoter driven Gaussia luciferase with ∆24E1A, the co-infected NE tumor secreted higher levels of Gaussia luciferase as compared to the INSM1p-Gaussia virus alone. In a mouse subcutaneous xenograft tumor model, the combination viruses secreted detectable level of Gaussia luciferase after infecting an INSM1-positive NE lung tumor for ≥12 days. Therefore, the INSM1-promoter specific conditional replicating adenovirus represents a sensitive diagnostic tool to aid clinicians in the detection of NE tumors.


Assuntos
Terapia Genética , Luciferases/genética , Tumores Neuroendócrinos/genética , Proteínas Repressoras/genética , Adenoviridae/genética , Animais , Carcinoma Neuroendócrino , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica , Vetores Genéticos , Humanos , Luciferases/biossíntese , Camundongos , Tumores Neuroendócrinos/diagnóstico , Tumores Neuroendócrinos/patologia , Regiões Promotoras Genéticas
16.
Blood ; 126(16): 1952-64, 2015 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-26333777

RESUMO

Platelet-leukocyte interactions on activated endothelial cells play an important role during microvascular occlusion under oxidative stress conditions. However, it remains poorly understood how neutrophil-platelet interactions are regulated during vascular inflammation. By using intravital microscopy with mice lacking nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 2 (NOX2) and their bone marrow chimera, we demonstrated that NOX2 from both hematopoietic and endothelial cells is crucial for neutrophil-platelet interactions during tumor necrosis factor alpha-induced venular inflammation. Platelet NOX2-produced reactive oxygen species (ROS) regulated P-selectin exposure upon agonist stimulation and the ligand-binding function of glycoprotein Ibα. Furthermore, neutrophil NOX2-generated ROS enhanced the activation and ligand-binding activity of αMß2 integrin following N-formyl-methionyl-leucyl phenylalanine stimulation. Studies with isolated cells and a mouse model of hepatic ischemia/reperfusion injury revealed that NOX2 from both platelets and neutrophils is required for cell-cell interactions, which contribute to the pathology of hepatic ischemia/reperfusion injury. Platelet NOX2 modulated intracellular Ca(2+) release but not store-operated Ca(2+) entry (SOCE), whereas neutrophil NOX2 was crucial for SOCE but not intracellular Ca(2+) release. Different regulation of Ca(2+) signaling by platelet and neutrophil NOX2 correlated with differences in the phosphorylation of AKT, ERK, and p38MAPK. Our results indicate that platelet and neutrophil NOX2-produced ROS are critical for the function of surface receptors essential for neutrophil-platelet interactions during vascular inflammation.


Assuntos
Plaquetas/metabolismo , Comunicação Celular , Glicoproteínas de Membrana/metabolismo , NADPH Oxidases/metabolismo , Neutrófilos/enzimologia , Vasculite/enzimologia , Animais , Plaquetas/patologia , Cálcio/metabolismo , Sinalização do Cálcio/genética , Feminino , Humanos , Sistema de Sinalização das MAP Quinases/genética , Masculino , Glicoproteínas de Membrana/genética , Camundongos , Camundongos Knockout , NADPH Oxidase 2 , NADPH Oxidases/genética , Neutrófilos/patologia , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Vasculite/genética , Vasculite/patologia , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
18.
Trials ; 16: 217, 2015 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-25972018

RESUMO

BACKGROUND: Obesity-related diseases have a profound economic impact on health care systems. Laser acupuncture has been shown to have beneficial effects on obesity. However, to our knowledge, those trials were either non-randomized, non-blinded or included low-calorie diet control. We have, therefore, designed a patient-assessor-blinded, randomized, sham-controlled crossover trial to investigate the significance of laser acupuncture on obesity. METHODS/DESIGN: 104 subjects above 20 years of age with a body mass index (BMI) of over 25 kg/m(2) will be divided into 2 groups: experimental and control. Each subject will receive the treatment relevant to their group 3 times a week for 8 weeks. After 8 weeks of treatment the subject will enter a 2-week washout period, after which the subjects will switch groups. Measurements will include BMI, body fat percentage, waist-to-hip ratio (WHR), waist circumference, hip circumference, skinfold thickness, thigh circumference, body fat, blood pressure, heart rate, hunger and the 36-item Short-Form Health Survey (SF-36). DISCUSSION: The results of this study will provide the basis for future large-scale multicenter trials investigating the effects of laser acupuncture on obesity. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02167308 ; registration date: 14 June 2014.


Assuntos
Terapia por Acupuntura/instrumentação , Terapia a Laser/instrumentação , Lasers Semicondutores/uso terapêutico , Obesidade/terapia , Terapia por Acupuntura/efeitos adversos , Terapia por Acupuntura/métodos , Adiposidade , Adulto , Antropometria , Índice de Massa Corporal , Protocolos Clínicos , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Terapia a Laser/efeitos adversos , Terapia a Laser/métodos , Lasers Semicondutores/efeitos adversos , Masculino , Obesidade/diagnóstico , Obesidade/fisiopatologia , Projetos de Pesquisa , Inquéritos e Questionários , Taiwan , Fatores de Tempo , Resultado do Tratamento , Redução de Peso , Adulto Jovem
19.
Cell Mol Life Sci ; 72(14): 2627-43, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25650236

RESUMO

Platelets primarily mediate hemostasis and thrombosis, whereas leukocytes are responsible for immune responses. Since platelets interact with leukocytes at the site of vascular injury, thrombosis and vascular inflammation are closely intertwined and occur consecutively. Recent studies using real-time imaging technology demonstrated that platelet-neutrophil interactions on the activated endothelium are an important determinant of microvascular occlusion during thromboinflammatory disease in which inflammation is coupled to thrombosis. Although the major receptors and counter receptors have been identified, it remains poorly understood how heterotypic platelet-neutrophil interactions are regulated under disease conditions. This review discusses our current understanding of the regulatory mechanisms of platelet-neutrophil interactions in thromboinflammatory disease.


Assuntos
Plaquetas/fisiologia , Comunicação Celular , Proteínas de Membrana/fisiologia , Neutrófilos/fisiologia , Anemia Falciforme/metabolismo , Anemia Falciforme/patologia , Plaquetas/enzimologia , Plaquetas/metabolismo , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patologia , Células Endoteliais/patologia , Humanos , Proteínas de Membrana/metabolismo , Modelos Biológicos , Neutrófilos/enzimologia , Neutrófilos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais
20.
J Craniomaxillofac Surg ; 43(3): 382-9, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25600627

RESUMO

BACKGROUND: Carved autologous costal cartilage and porous polyethylene implants (Medpor) are the most common approaches for total ear reconstruction, but these approaches may have inconsistent cosmetic outcomes, a high risk of extrusion, or other surgical complications. Engineering ear cartilage to emulate native auricular tissue is an appealing approach, but often the cell-seeded scaffolds are susceptible to shrinkage and architectural changes when placed in vivo. The aim of this study was to assess the most favorable conditions for in vitro pre-culture of cell-seeded type I collagen scaffolds prior to in vivo implantation. METHODS: Sheep auricular chondrocytes were seeded into this type I collagen scaffold. The cell-seeded constructs were cultured in either static or dynamic conditions for two days or two weeks and then implanted into nude mice for another six weeks. The harvested constructs were evaluated histologically, immunohistochemically, and biochemically. RESULTS: Robust neo-cartilage formation was found in these collagen scaffolds seeded with auricular chondrocytes, which was comparable to native cartilage morphologically, histologically, and biochemically. Culture under dynamic conditions prior to implantation improved the neo-cartilage formation histologically and biochemically. CONCLUSION: Dynamic culture of this cell-seeded fibrous collagen material could permit predictable engineered auricular cartilage and a promising approach for external ear reconstruction.


Assuntos
Condrócitos/fisiologia , Colágeno Tipo I/química , Cartilagem da Orelha/citologia , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Animais , Técnicas de Cultura de Células , Separação Celular/métodos , Células Cultivadas , Condrogênese/fisiologia , DNA/análise , Cartilagem da Orelha/anatomia & histologia , Cartilagem da Orelha/química , Elastina/análise , Glicosaminoglicanos/análise , Hidroxiprolina/análise , Camundongos , Camundongos Nus , Ovinos , Tela Subcutânea/cirurgia , Propriedades de Superfície , Fatores de Tempo
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