RESUMO
Success of human myocardial tissue engineering for cardiac repair has been limited by adverse effects of scaffold materials, necrosis at the tissue core, and poor survival after transplantation due to ischemic injury. Here, we report the development of scaffold-free prevascularized human heart tissue that survives in vivo transplantation and integrates with the host coronary circulation. Human embryonic stem cells (hESCs) were differentiated to cardiomyocytes by using activin A and BMP-4 and then placed into suspension on a rotating orbital shaker to create human cardiac tissue patches. Optimization of patch culture medium significantly increased cardiomyocyte viability in patch centers. These patches, composed only of enriched cardiomyocytes, did not survive to form significant grafts after implantation in vivo. To test the hypothesis that ischemic injury after transplantation would be attenuated by accelerated angiogenesis, we created "second-generation," prevascularized, and entirely human patches from cardiomyocytes, endothelial cells (both human umbilical vein and hESC-derived endothelial cells), and fibroblasts. Functionally, vascularized patches actively contracted, could be electrically paced, and exhibited passive mechanics more similar to myocardium than patches comprising only cardiomyocytes. Implantation of these patches resulted in 10-fold larger cell grafts compared with patches composed only of cardiomyocytes. Moreover, the preformed human microvessels anastomosed with the rat host coronary circulation and delivered blood to the grafts. Thus, inclusion of vascular and stromal elements enhanced the in vitro performance of engineered human myocardium and markedly improved viability after transplantation. These studies demonstrate the importance of including vascular and stromal elements when designing human tissues for regenerative therapies.
Assuntos
Miócitos Cardíacos/transplante , Transplante de Células-Tronco/métodos , Animais , Diferenciação Celular , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/transplante , Feminino , Humanos , Miocárdio/citologia , Miócitos Cardíacos/citologia , Ratos , Ratos Sprague-Dawley , Engenharia Tecidual/métodos , Alicerces TeciduaisRESUMO
PURPOSE: To describe the biologic and clinical features of children with primitive neuroectodermal tumors (PNETs) arising in the pineal region (pineoblastomas) and evaluate prospectively the efficacy of radiation therapy (RT) and/or chemotherapy. PATIENTS AND METHODS: Between 1986 and 1992, 25 children with PNETs of the pineal region were treated as part of a Childrens Cancer Group study. Eight infants less than 18 months of age were nonrandomly treated with eight-drugs-in-1-day chemotherapy without RT. The remaining 17 patients were treated with craniospinal RT and randomized to receive either vincristine, lomustine (CCNU), and prednisone or the eight-drugs-in-1-day regimen. RESULTS: Of 24 completely staged patients, 20 (83%) had localized disease at diagnosis. All infants developed progressive disease a median of 4 months from the start of treatment. Of the 17 older patients treated with RT and chemotherapy, the Kaplan-Meier estimate of progression-free survival (PFS) at 3 years is 61% +/- 13%. This is superior to the PFS of children with other supratentorial PNETs (P = .026). Following RT, 12 of 17 patients (70.6%) had a residual pineal region mass, which persisted for as long as 5 years before resolving; only four subsequently developed progressive disease. CONCLUSION: (1) Eight-in-1 chemotherapy without RT appears to be ineffective therapy for young children with PNETs of the pineal region. (2) For children more than 18 months of age at diagnosis treated with craniospinal RT and chemotherapy, the PFS is superior to that of children with other supratentorial PNETs. (3) A residual enhancing mass following RT is not predictive of treatment failure.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/radioterapia , Glândula Pineal , Pinealoma/tratamento farmacológico , Pinealoma/radioterapia , Adolescente , Adulto , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/cirurgia , Criança , Pré-Escolar , Terapia Combinada , Progressão da Doença , Feminino , Humanos , Lactente , Lomustina/administração & dosagem , Masculino , Neoplasia Residual , Pinealoma/mortalidade , Pinealoma/cirurgia , Prednisona/administração & dosagem , Prognóstico , Estudos Prospectivos , Taxa de Sobrevida , Vincristina/administração & dosagemRESUMO
PURPOSE: From 1986 to 1992, "eight-drugs-in-one-day" (8-in-1) chemotherapy both before and after radiation therapy (XRT) (54 Gy tumor/36 Gy neuraxis) was compared with vincristine, lomustine (CCNU), and prednisone (VCP) after XRT in children with untreated, high-stage medulloblastoma (MB). PATIENTS AND METHODS: Two hundred three eligible patients with an institutional diagnosis of MB were stratified by local invasion and metastatic stage (Chang T/M) and randomized to therapy. Median time at risk from study entry was 7.0 years. RESULTS: Survival and progression-free survival (PFS) +/- SE at 7 years were 55%+/-5% and 54%+/-5%, respectively. VCP was superior to 8-in-1 chemotherapy, with 5-year PFS rates of 63%+/-5% versus 45%+/-5%, respectively (P = .006). Upon central neuropathology review, 188 patients were confirmed as having MB and were the subjects for analyses of prognostic factors. Children aged 1.5 to younger than 3 years had inferior 5-year estimates of PFS, compared with children 3 years old or older (P = .0014; 32%+/-10% v 58%+/-4%, respectively). For MB patients 3 years of age or older, the prognostic effect of tumor spread (MO v M1 v M2+) on PFS was powerful (P = .0006); 5-year PFS rates were 70%+/-5%, 57%+/-10%, and 40%+/-8%, respectively. PFS distributions at 5 years for patients with M0 tumors with less than 1.5 cm2 of residual tumor, versus > or = 1.5 cm2 of residual tumor by scan, were significantly different (P = .023; 78%+/-6% v 54%+/-11%, respectively). CONCLUSION: VCP plus XRT is a superior adjuvant combination compared with 8-in-1 chemotherapy plus XRT. For patients with M0 tumors, residual tumor bulk (not extent of resection) is a predictor for PFS. Patients with M0 tumors, > or = 3 years with < or = 1.5 cm2 residual tumor, had a 78%+/-6% 5-year PFS rate. Children younger than 3 years old who received a reduced XRT dosage had the lowest survival rate.
Assuntos
Neoplasias Cerebelares/patologia , Meduloblastoma/patologia , Tumores Neuroectodérmicos Primitivos/patologia , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Cerebelares/tratamento farmacológico , Neoplasias Cerebelares/radioterapia , Quimioterapia Adjuvante , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Meduloblastoma/tratamento farmacológico , Meduloblastoma/radioterapia , Metástase Neoplásica , Estadiamento de Neoplasias , Tumores Neuroectodérmicos Primitivos/tratamento farmacológico , Tumores Neuroectodérmicos Primitivos/radioterapia , Prognóstico , Análise de SobrevidaRESUMO
PURPOSE: This study evaluates the response of new or recurrent head and neck cancers and the response of associated normal tissues to high dose reirradiation with curative intent. METHODS AND MATERIALS: From 1964 to 1991, 15 patients with in-field new second head and neck cancers and 85 patients with recurrent head and neck cancers have had high-dose reirradiation that overlapped with previously irradiated volumes. Reirradiation was given only to patients with no more than apparent minimal clinical radiation effects from the first radiation course. The reirradiation consisted of external beam only in 82 patients, external beam plus intracavitary or interstitial implant irradiation in 14 patients, and interstitial implant irradiation only in four patients. The combined overlapping dose from both the initial and subsequent irradiation (including brachytherapy) was 69-89 Gy in 14 patients, 90-99 Gy in 15 patients, 100-119 Gy in 27 patients, and 120 Gy or greater in 44 patients. Four patients had areas of overlap that received greater than 180 Gy. RESULTS: The actuarial 5-year survival was 37% for patients with new second primary cancers and 17% for patients with recurrent cancers. Loco-regional tumor control was achieved in 60% of the patients with new tumors and in 27% of the patients with recurrent tumors. Nine of the 100 patients developed severe adverse normal tissue effects from the reirradiation. CONCLUSION: High-dose reirradiation of head and neck cancers can be successful curative treatment in a significant proportion of patients. It is associated with substantial but acceptable risks in properly selected patients.
Assuntos
Neoplasias de Cabeça e Pescoço/radioterapia , Recidiva Local de Neoplasia/radioterapia , Segunda Neoplasia Primária/radioterapia , Relação Dose-Resposta a Droga , Estudos de Avaliação como Assunto , Neoplasias de Cabeça e Pescoço/mortalidade , Humanos , Recidiva Local de Neoplasia/mortalidade , Segunda Neoplasia Primária/mortalidade , Doses de RadiaçãoRESUMO
PURPOSE: To assess the impact of fractionation schedule, chemotherapy, and tumor location on local control and survival in patients treated with definitive irradiation for carcinoma of the pharyngeal walls. METHODS AND MATERIALS: Between May 1971 and December 1991, 74 patients with previously untreated squamous cell carcinoma of the pharyngeal walls (excluding nasopharynx, tonsil, and pyriform sinus) were treated with radical megavoltage irradiation with or without chemotherapy at Oregon Health Sciences University. RESULTS: Two-year local control rates by stage were: T1: 100%, T2: 55%, T3: 31%, and T4: 29% . Twice-a-day irradiation improved local control rates as compared with once-a-day irradiation for patients with Stage T3 lesions, with 5 out of 7 (71.4%) vs. 4 out of 19 (21%) patients controlled at 2 years (p = 0.015). No improvement was seen in 2-year local control of all stages when chemotherapy was used in conjunction with once-a-day fractionation; however, six of eight patients (75%) treated with twice-a-day irradiation combined with either induction or concurrent chemotherapy had local control. The 2-year local control rate of 100% (6 out of 6) for the group of patients treated with concurrent chemotherapy and b.i.d. irradiation (all with Stage T3 and T4 tumors) is a dramatic improvement over the 2-year local control rate of 30% (10 out of 33) for our entire group of patients with Stage T3 and T4 tumors. Local control rates did not differ by tumor location on the pharyngeal walls. Adjusted disease-specific survival rates by stage were: 1: 100%, II: 85%, III: 58%, IV: 40%. Overall survival rates by stage were: I: 75%, II: 67%, III: 33%, IV: 30%. CONCLUSION: We advocate radical irradiation as the primary therapy for pharyngeal wall carcinomas with the use of twice-a-day fractionation for Stages T2-T4. Our preliminary results with concurrent chemotherapy and b.i.d. irradiation for advanced T3 and T4 tumors appear to be comparable to reported results with hyperfractionated radiation alone. The relative contribution of chemotherapy to b.i.d. irradiation cannot be determined from this small retrospective series; however, in view of the relatively poor results for patients with advanced stage disease, we feel this treatment combination deserves further investigation.
Assuntos
Carcinoma de Células Escamosas/radioterapia , Neoplasias Faríngeas/radioterapia , Adolescente , Adulto , Idoso , Antineoplásicos/uso terapêutico , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/patologia , Terapia Combinada , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estadiamento de Neoplasias , Neoplasias Faríngeas/tratamento farmacológico , Neoplasias Faríngeas/patologia , Dosagem RadioterapêuticaRESUMO
OBJECTIVE: To conduct a systematic review of evidence relating to management of mild chronic hypertension during pregnancy, including associated risks, benefits, and harms of treatment with antihypertensive agents, nonpharmacologic measures, and aspirin and benefits of various monitoring strategies. DATA SOURCES: Using four broad search strategies, we searched English and non-English-language citations in 16 electronic databases from their inception to February 1999 and consulted relevant textbooks, references, and experts. STUDY SELECTION: Reviewers screened 6228 abstracts and found 215 articles that met multiple prespecified patient selection, study population, and design criteria. TABULATION, INTEGRATION, AND RESULTS: Forty-six studies consistently showed that chronic hypertension triples the risk for perinatal mortality (odds ratio [OR] 3.4; 95% confidence interval [CI] 3.0, 3.7) and doubles the risk for placental abruption (OR 2.1; 95% CI 1.1, 3.9). Thirteen small, randomized controlled trials had inadequate power to rule in or rule out moderate-to-large (20%-50%) benefits of antihypertensive treatment. Possible adverse effects were fetal renal failure when angiotensin-converting enzyme inhibitors are used in the second or third trimester and growth restriction when atenolol is used early in pregnancy. Trials showed that aspirin neither reduces nor increases perinatal and maternal morbidity, but they did not rule out possible small-to moderate beneficial or adverse effects. No studies provide guidance on benefits or consequences of various nonpharmacologic therapies or monitoring strategies. CONCLUSION: Mild chronic hypertension is associated with increased maternal and fetal risks. Beneficial treatment and monitoring regimens are not clear, but some treatments, such as angiotensin-converting enzyme inhibitors, are best avoided.
Assuntos
Hipertensão/terapia , Complicações Cardiovasculares na Gravidez/terapia , Descolamento Prematuro da Placenta/etiologia , Anti-Hipertensivos/uso terapêutico , Doença Crônica , Feminino , Humanos , Hipertensão/tratamento farmacológico , Lactente , Mortalidade Infantil , Seleção de Pacientes , Gravidez , Complicações Cardiovasculares na Gravidez/tratamento farmacológico , Medição de RiscoRESUMO
HYPOTHESIS: The adaptation of new techniques in treatment of epidermoid carcinoma of the anal canal during the past 3 decades has improved clinical outcomes. DESIGN: Retrospective consecutive case review. SETTING: A university hospital and Veterans Affairs medical center. PATIENTS: Medical records of 76 consecutive patients treated for invasive epidermoid cancer of the anal canal between 1970 and 1999 were reviewed. Twenty-one patients were excluded because of inadequate staging information and/or follow-up of less than 12 months. MAIN OUTCOME MEASURES: Locoregional recurrence, survival, colostomy-free survival, and morbidity. RESULTS: Fifty-five patients composed the study population. Ten were treated during decade 1 (1970-1979), 16 in decade 2 (1980-1989), and 29 in decade 3 (1990-1999). Mean age and sex distributions were similar. The prevailing primary treatment modality changed during the course of the study from sequential treatment (chemotherapy then radiation therapy then radical surgery) to concurrent chemoradiation (70% and 0% of cases, respectively, in decade 1 to 7% and 76% of cases, respectively, in decade 3). Locoregional control (50%, 81%, and 93%; P =.01), crude survival (median, 28, 30, and 76 months), and colostomy-free survival (mean, 13, 90, and 80 months) improved during the 3 decades. There were no differences in major complications during the 3 decades (40%, 56%, and 41%). CONCLUSION: Primary treatment with concurrent chemoradiation has improved the local recurrence, survival, and colostomy-free survival rates in patients with invasive epidermoid carcinoma of the anal canal without increasing major morbidity.
Assuntos
Neoplasias do Ânus/terapia , Carcinoma de Células Escamosas/terapia , Adulto , Idoso , Neoplasias do Ânus/patologia , Neoplasias do Ânus/cirurgia , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , Quimioterapia Adjuvante , Colostomia , Fracionamento da Dose de Radiação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Complicações Pós-Operatórias/etiologia , Radioterapia Adjuvante , Estudos Retrospectivos , Análise de Sobrevida , Resultado do TratamentoRESUMO
OBJECT: Ependymomas in children continue to generate controversy regarding their histological diagnosis and grading. optimal management, and possible prognostic factors. To increase our knowledge of these tumors the authors addressed these issues in a cohort of children with prospectively staged ependymomas treated with radiotherapy and chemotherapy. METHODS: Children between the ages of 2 and 17.3 years harboring an intracranial ependymoma confirmed by a central review of the tumor's pathological characteristics were treated according to Children's Cancer Group Protocol 921 from 1986 to 1992. Treatment following surgery and postoperative tumor staging (including brain computerized tomography or magnetic resonance [MR] imaging, spinal MR imaging or myelography, and cerebrospinal fluid cytological investigation) included craniospinal irradiation with a local boost to the primary tumor and patient randomization to receive adjuvant chemotherapy with either 1) CCNU, vincristine, and prednisone, or 2) the eight-drugs-in-1-day regimen. Centralized review of the tumor pathological characteristics revealed 20 ependymomas and 12 anaplastic ependymomas in the 32 children included in the study. Diagnoses made at the individual institutions included anaplastic (malignant) ependymoma (15 patients), ependymoma (four patients), ependymoblastoma (nine patients), ependymoastrocytoma (one patient), and primitive neuroectodermal tumor (three patients), which were discordant with the centralized review diagnosis in 22 of 32 cases. Only three of the 32 patients had metastatic disease (two with M and one with M3 stages). At surgery, 47% of tumors were estimated to be totally resected. Among the 14 of 17 patients who suffered a relapse and were evaluated for site of relapse, 10 (71%) had an isolated local relapse, three (21%) had concurrent local and metastatic relapse, and only one (7%) had an isolated metastatic relapse. Kaplan-Meier estimates of 5-year progression-free survival (PFS) and overall survival rates were 50 +/- 10% and 64 +/- 9%, respectively. CONCLUSIONS: Predictors of PFS duration included an estimate of the extent of resection made at surgery (total compared with less than total, p = 0.0001) and the amount of residual tumor on postoperative imaging as verified by centralized radiological review (< or = 1.5 cm2 compared with > 1.5 cm2, p < 0.0001). No other factors, including centrally reviewed tumor histopathological type, location, metastasis and tumor (M and T) stages, patient age, race, gender, or chemotherapy treatment regimen significantly correlated with PFS duration. The pattern of predominantly local relapse and the important influence of residual tumor or the extent of resection on PFS duration confirms a prevailing impression that local disease control is the major factor in the prediction of outcome of ependymoma. Survival rates were comparable with those reported by other investigators who have treated patients with similar doses of radiation and no chemotherapy.
Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/radioterapia , Ependimoma/tratamento farmacológico , Ependimoma/radioterapia , Cuidados Pós-Operatórios , Adolescente , Adulto , Neoplasias Encefálicas/patologia , Criança , Pré-Escolar , Estudos de Coortes , Terapia Combinada , Ependimoma/patologia , Feminino , Humanos , Lactente , Masculino , Estadiamento de Neoplasias , Prognóstico , Estudos Prospectivos , Análise de SobrevidaRESUMO
Sequential intraarterial chemotherapy using bleomycin and methotrexate followed by high dose radiation and surgery was evaluated in 10 patients with stage III and IV squamous carcinomas of the maxillary sinus. Seven of 10 patients had extensive tumor necrosis in the surgical specimen, and no evidence of residual tumor was found in 4 of these patients. After a median follow up period of 24 months, there has been only one local recurrence in resected patients. Three patients died from pulmonary metastases. Although many unanswered questions remain regarding the efficacy of triple therapy for maxillary sinus malignancy, these results are encouraging and establish that surgical resection and healing are not compromised by preoperative chemotherapy and radiation.
Assuntos
Carcinoma de Células Escamosas/terapia , Seio Maxilar , Neoplasias dos Seios Paranasais/terapia , Adulto , Idoso , Antineoplásicos/administração & dosagem , Carcinoma de Células Escamosas/radioterapia , Carcinoma de Células Escamosas/cirurgia , Humanos , Infusões Intra-Arteriais , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias dos Seios Paranasais/radioterapia , Neoplasias dos Seios Paranasais/cirurgia , Dosagem Radioterapêutica , Artérias TemporaisRESUMO
BACKGROUND: Surgical resection of tongue base cancer can leave the patient with significant functional deficits. Other therapies, such as external beam radiation followed by neck dissection and radiation implants, have shown equal tumor control with good functional outcome. METHODS: Between March 1991 and July 1999, 12 patients at Oregon Health Sciences University, the Portland Veterans Administration Medical Center and West Virginia University School of Medicine Hospital were treated with external beam radiation followed by neck dissection and Ir192 implants. Two patients had T1 disease, two had T2, five patients had T3 tumors, and three had T4 tumors. Six had N2a necks, three had N2b necks, and three had N2c. Follow-up ranged from 13 months to 8 years. RESULTS: After external beam radiation, five patients had complete response and seven had partial response in the neck without complications. One patient underwent a unilateral radical neck dissection, eight had unilateral selective neck dissections involving levels I to IV, and three had dissections involving levels I to III. One of the five patients who had a complete clinical response in the neck had pathologically positive nodes. One patient had a pulmonary embolus that was treated and had no permanent sequelae. There were three complications from brachytherapy. Two patients had soft tissue necrosis at the primary site and one patient had radionecrosis of the mandible. All healed without further therapy. One patient had persistent disease and underwent a partial glossectomy but died of local disease. Distant metastasis developed in two patients. All others show no evidence of disease and are able to eat a normal diet by mouth. CONCLUSION: This combination of therapies should be considered when treating tongue base cancer.
Assuntos
Braquiterapia , Carcinoma de Células Escamosas/terapia , Esvaziamento Cervical , Neoplasias da Língua/terapia , Idoso , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/radioterapia , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias da Língua/patologia , Neoplasias da Língua/radioterapia , Resultado do TratamentoRESUMO
The effect of ginseng extract G115 on reproductive performance was studied in two generations of Sprague-Dawley rats. Animals of both sexes were fed wither control diet or diet supplemented with ginseng extract G115 at dose levels of 1 . 5, 5 or 15 mg/kg body weight/day. Parameters of reproduction and lactation in the treated groups were comparable to those of the controls for two generations of dams and pups. For F1 males and females, no treatment-related effects were seen in weekly body weights and food consumption, haematological and clinical chemical data, and ophthalmic, gross and histopathological examinations. The gross autopsies of F1 and F2 animals also revealed no significant treatment-related findings.
Assuntos
Panax , Plantas Medicinais , Reprodução/efeitos dos fármacos , Animais , Peso Corporal/efeitos dos fármacos , Feminino , Masculino , Extratos Vegetais/farmacologia , Gravidez , Ratos , Ratos EndogâmicosRESUMO
Cranial nerve damage following head and neck radiotherapy is an unusual event. Cranial neuropathy following concurrent chemotherapy and radiotherapy is unreported. The authors report a case of a 54-year-old man treated with curative chemotherapy and radiotherapy for a stage III nasopharyngeal carcinoma who developed an unilateral hypoglossal nerve palsy five years after therapy. Follow-up examination and magnetic resonance imaging (MRI) show no evidence of recurrent disease. Hypoglossal nerve injury occurring after head and neck radiotherapy is an indirect effect due to progressive soft tissue fibrosis and loss of vascularity. This process develops over years leading to nerve entrapment and permanent damage. Cranial nerve palsies, including damage to the hypoglossal nerve, can develop years after therapy with no evidence of tumour recurrence. Chemotherapy and radiotherapy have improved progression-free and overall survival in advanced nasopharyngeal cancer. As more patients achieve long-term tumour control following chemotherapy and radiotherapy, we must be cognizant of potential late injury to cranial nerves.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Doenças do Nervo Hipoglosso/etiologia , Neoplasias Nasofaríngeas/terapia , Lesões por Radiação/etiologia , Radioterapia de Alta Energia/efeitos adversos , Terapia Combinada , Seguimentos , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
This paper addresses implications of recent tobacco legislation, policy, and tobacco use among youth in the context of health care policy and services. Tobacco use prevalence and definitions and diagnoses of nicotine addiction and dependence are described. Assessment of smoking prevalence in Texas provides a case study of the problem and potential solutions for tobacco use among youth. The case study highlights specific implications to be considered when providing health care focused on prevention and risk reduction for youth. The paper concludes with implications and critical Internet resources for health care providers engaging in youth tobacco control.
Assuntos
Indústria Farmacêutica/legislação & jurisprudência , Política de Saúde/legislação & jurisprudência , Promoção da Saúde/legislação & jurisprudência , Fumar/legislação & jurisprudência , Adolescente , Comportamento do Adolescente , Comportamentos Relacionados com a Saúde , Humanos , Internet , Prevalência , Fumar/epidemiologia , Prevenção do Hábito de Fumar , Texas/epidemiologia , TabagismoRESUMO
Obesity is a common nutritional disturbance in children, ranging from 18% to 30% in children of various ages. It is even more problematic among ethnically diverse populations. Because childhood is a critical period for the initiation of obesity, appropriate measurement and assessment of children at risk are essential. Current approaches to the measurement of fatness and classification of obesity vary in their accuracy and reproducibility. Measurement of body fatness in children and adolescents is most accurately estimated by combinations of measures.
Assuntos
Obesidade/diagnóstico , Obesidade/terapia , Adolescente , Criança , Pré-Escolar , Humanos , Lactente , Recém-Nascido , Avaliação em Enfermagem , Avaliação Nutricional , Obesidade/classificação , Obesidade/etiologia , Reprodutibilidade dos Testes , Fatores de RiscoRESUMO
Obesity is a common nutritional disturbance of children and affects 25% to 30% of children and adolescents. This paper examines obesity in childhood, the measurement of obesity in children, and the relationship of obesity to coronary heart disease risks and discusses weight reduction issues in children. Clinically useful definitions of obesity in children have not been established, although the body mass index, together with anthropometric measurements, may provide the practitioner with useful assessment parameters. Discussions of weight in children must acknowledge the nutritional requirements of the normally occurring growth process. Because growth (and subsequently weight) varies widely among children even of the same age, measurement, classification, and control of weight must take into account the growth process and growth requirements. Interventions in childhood obesity should be directed toward family involvement in the chosen strategy and nutritional prudence coupled with typical activity.
Assuntos
Obesidade , Adolescente , Terapia Comportamental , Índice de Massa Corporal , Criança , Pré-Escolar , Dieta Redutora , Exercício Físico , Família/psicologia , Humanos , Profissionais de Enfermagem , Avaliação Nutricional , Obesidade/diagnóstico , Obesidade/etiologia , Obesidade/terapia , Prevalência , Fatores de RiscoRESUMO
Complex tissues contain multiple cell types that are hierarchically organized within morphologically and functionally distinct compartments. Construction of engineered tissues with optimized tissue architecture has been limited by tissue fabrication techniques, which do not enable versatile microscale organization of multiple cell types in tissues of size adequate for physiological studies and tissue therapies. Here we present an 'Intaglio-Void/Embed-Relief Topographic molding' method for microscale organization of many cell types, including induced pluripotent stem cell-derived progeny, within a variety of synthetic and natural extracellular matrices and across tissues of sizes appropriate for in vitro, pre-clinical, and clinical studies. We demonstrate that compartmental placement of non-parenchymal cells relative to primary or induced pluripotent stem cell-derived hepatocytes, compartment microstructure, and cellular composition modulate hepatic functions. Configurations found to sustain physiological function in vitro also result in survival and function in mice for at least 4 weeks, demonstrating the importance of architectural optimization before implantation.