RESUMO
Objective: To introduce a new self-developed irrigation device(SID) that does not employ a sheath or an irrigation-suction system and evaluate to its efficiency in transcanal endoscopic ear surgery (TEES) for attic cholesteatoma. Methods: 38 patients who were subjected to TEES for attic cholesteatoma between October 2019 to June 2021 were included in this study, including 17 males and 21 females with an average age of (38.6±11.9) years. SID and underwater continuous drilling were used during operation. Width of endoscope and irrigation speed were measured when SID was applied. The operating time, surgical view and complications were compared between two groups. Results: The width of the endoscope was 3.5-4.6 mm in diameter and the irrigation speed was 20-40 ml/min when SID was used. SID cleaned the lens at the tip of the endoscope and created a clear field of view during TEES. The operation time was (86.6±18.1) min. The skin of the external ear canal was found injured during operation in 3 patients, but there were no complications such as necrosis of the flap, stenosis of external ear canal, sensorineural hearing loss, facial paralysis and cerebrospinal fluid leakage. Conclusions: SID is simple and enhances the efficacy of TEES, providing a new irrigation choice in TEES for attic cholesteatoma.
Assuntos
Colesteatoma da Orelha Média , Procedimentos Cirúrgicos Otológicos , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Colesteatoma da Orelha Média/cirurgia , Orelha Média/cirurgia , SucçãoRESUMO
Objective: To evaluate the results of butterfly cartilage myringoplasty for anterior quadrant tympanic perforation under endoscope. Methods: Thirty-eight patients with anterior quadrant tympanic perforations who were subjected to endoscopic butterfly cartilage myringoplasty from April 2016 to October 2018 were included in this study, including 16 males and 22 females, with an average age of (34.5±14.2) years. The patients were reviewed retrospectively, and the pre-and post-operative pure tone audiometry (PTA) thresholds, pre-and post-operative air-bone gaps (ABG), post-operative graft success rates and complications were evaluated. SPSS 23.0 was used to analyze data. Results: Mean post-operative follow-up duration was (9.4±3.1) months (range 6-18 months). The graft survival rate was 94.7% (36/38) . The preoperative and postoperative mean PTA was (30.9±8.9) dB HL and (21.4±7.7) dB HL respectively. Preoperative and postoperative mean ABG was (18.4±6.3) dB and (10.8±6.0) dB respectively. There was significant difference between pre-and postoperative PTA and ABG (t=5.353 and 4.162, P<0.05 for both). A postoperative ABG reduction of (8.3±1.5) dB was reached. Two (4.7%) patients had postoperative myringitis, two (4.7%) had recurrent perforation, and one (2.4%) had lateral healing of transplanted tympanic membrane in the postoperative follow-ups. No intratympanic cholesteatoma was observed. Conclusions: Endoscopic butterfly inlay myringoplasty is a reliable, minimally invasive alternative method to repair anterior tympanic membrane perforations, with high closure rate and low risk of complications.
Assuntos
Miringoplastia , Perfuração da Membrana Timpânica , Adulto , Cartilagem , Endoscópios , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Membrana Timpânica , Perfuração da Membrana Timpânica/cirurgia , Adulto JovemRESUMO
Objective: To introduce a self-developed bone dust collector designed by the authors and evaluate its efficiency in mastoid obliteration following mastoidectomy. Methods: Consecutive patients, from April 2017 to March 2018, who prepared to receive mastoidectomy were randomly divided into two groups, and in each group the bone dust was harvested by self-developed bone dust collector or by conventional used method respectively in mastoidectomy. The amount of the harvested bone dust and the time consumed in the collecting procedure were compared between two groups. The infection of the bone dust after mastoid obliteration was also evaluated during follow up. Results: 33 patients were recruited in bone dust collector group, and 31 patients in conventional method group.There is no significance of difference between two groups in sex ratio, age and pneumatization of mastoid cells (P>0.05 for all). The median amount of bone dust harvested by bone dust collector was significantly larger than that collected by conventional method (1.8 g vs 1.1 g, P<0.05). The median time spent in bone dust collector group was significantly shorter than that spent in conventional method group (4 minutes vs 6 minutes, P<0.05). No bone dust infection was found in the follow-up in all patients. Conclusion: The present self-developed bone dust collector is a easy and useful apparatus which can significantly improve the efficiency of collecting bone dust in mastoidectomy.
Assuntos
Poeira , Processo Mastoide/cirurgia , Mastoidectomia/instrumentação , Manejo de Espécimes/instrumentação , Feminino , Humanos , MasculinoRESUMO
Graphitization occurs during the long-term service of a diamond-like carbon (DLC) modified artificial joint. Then, DLC wear debris, which are carbon particles with different sp2/sp3 ratios and sizes ranging from the nano- to micro-meter scale produced. In this paper, to promote the application of DLC coating for artificial joint modification, the cytotoxicity of DLC debris (nano-carbon particles, NCs) with different sp2/sp3 ratios was studied. The microstructure and physical characteristics of NCs with different sp2/sp3 ratios were investigated by Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), Transmission Electron Microscope (TEM) and Dynamic Light Scattering (DLS). Meanwhile, osteoblasts and macrophages were applied to characterize the cytotoxicity of the NCs. In vitro cytotoxicity assay results indicated that cells incubated with NCs of different sp2/sp3 ratios had greater osteogenic capacity, and these particles caused a weaker immune response in comparison with CoCrMo particles. Taken together, the results indicated that NCs with different sp2/sp3 ratios presented a good cytocompatibility than CoCrMo particles. But no significant differences were observed among NCs with different sp2/sp3 ratios. The better cytocompatibility of NCs is mainly attributable to their surface charge.
Assuntos
Carbono/toxicidade , Nanoestruturas/toxicidade , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Humanos , Interleucina-6/metabolismo , Macrófagos/efeitos dos fármacos , Camundongos , Microscopia Eletrônica de Transmissão , Modelos Teóricos , Nanoestruturas/química , Osteoblastos/efeitos dos fármacos , Espectroscopia Fotoeletrônica , Células RAW 264.7 , Fator de Necrose Tumoral alfa/metabolismoRESUMO
While a diamond-like carbon (DLC)-coated joint prosthesis represents the implant of choice for total hip replacement in patients, it also leads to concern due to the cytotoxicity of wear debris in the form of graphite nanoparticles (GNs), ultimately limiting its clinical use. In this study, the cytotoxicity of various GN doses was evaluated. Mouse macrophages and osteoblasts were incubated with GNs (<30 nm diameter), followed by evaluation of cytotoxicity by means of assessing inflammatory cytokines, results of alkaline phosphatase assays, and related signaling protein expression. Cytotoxicity evaluation showed that cell viability decreased in a dose-dependent manner (10-100 µg ml-1), and steeply declined at GNs concentrations greater than 30 µg ml-1. Noticeable cytotoxicity was observed as the GN dose exceeded this threshold due to upregulated receptor of activator of nuclear factor kB-ligand expression and downregulated osteoprotegerin expression. Meanwhile, activated macrophage morphology was observed as a result of the intense inflammatory response caused by the high doses of GNs (>30 µg ml-1), as observed by the increased release of TNF-α and IL-6. The results suggest that GNs had a significant dose-dependent cytotoxicity in vitro, with a lethal dose of 30 µg ml-1 leading to dramatic increases in cytotoxicity. Our GN cytotoxicity evaluation indicates a safe level for wear debris-related arthropathy and could propel the clinical application of DLC-coated total hip prostheses.
Assuntos
Materiais Revestidos Biocompatíveis/toxicidade , Grafite/toxicidade , Prótese Articular , Nanopartículas/toxicidade , Animais , Carbono/química , Células Cultivadas , Materiais Revestidos Biocompatíveis/administração & dosagem , Materiais Revestidos Biocompatíveis/química , Diamante/química , Relação Dose-Resposta a Droga , Grafite/administração & dosagem , Grafite/química , Humanos , Mediadores da Inflamação/metabolismo , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Teste de Materiais , Camundongos , Nanopartículas/administração & dosagem , Nanopartículas/química , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Osteogênese/efeitos dos fármacos , Falha de Prótese , Células RAW 264.7RESUMO
Diamond-like carbon (DLC) films are potential candidates for artificial joint surface modification in biomedical applications, and the influence of the structural features of DLC surfaces on cell functions has attracted attention in recent decades. Here, the biocompatibility of DLC films with different structures was investigated using macrophages, osteoblasts and fibroblasts. The results showed that DLC films with a low ratio of sp(2)/sp(3), which tend to have a structure similar to that of diamond, led to less inflammatory, excellent osteogenic and fibroblastic reactions, with higher cell viability, better morphology, lower release of TNF-α (tumor necrosis factor-α) and IL-6 (interleukin-6), and higher release of IL-10 (interleukin-10). The results also demonstrated that the high-density diamond structure (low ratio of sp(2)/sp(3)) of DLC films is beneficial for cell adhesion and growth because of better protein adsorption without electrostatic repulsion. These findings provide valuable insights into the mechanisms underlying inhibition of an inflammatory response and the promotion of osteoblastogenesis and fibrous propagation, and effectively build a system for evaluating the biocompatibility of DLC films.
Assuntos
Tecnologia Biomédica/métodos , Diamante/química , Diamante/farmacologia , Adsorção , Animais , Bovinos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Citocinas/metabolismo , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Mediadores da Inflamação/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Macrófagos/ultraestrutura , Camundongos , Microscopia de Força Atômica , Microscopia de Fluorescência , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Soroalbumina Bovina/química , Análise Espectral RamanRESUMO
Development and selection of an ideal scaffold is of importance for tissue engineering. Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) is a biocompatible bioresorbable copolymer that belongs to the polyhydroxyalkanoate family. Because of its good biocompatibility, PHBHHx has been widely used as a cell scaffold for tissue engineering. This review focuses on the utilization of PHBHHx-based scaffolds in tissue engineering. Advances in the preparation, modification, and application of PHBHHx scaffolds are discussed.
Assuntos
Humanos , /química , Materiais Biocompatíveis/química , Caproatos/química , Engenharia Tecidual/métodos , Alicerces Teciduais/química , /uso terapêutico , Materiais Biocompatíveis/uso terapêutico , Osso e Ossos/fisiologia , Caproatos/uso terapêutico , Cartilagem/fisiologia , Liofilização , Músculo Liso/fisiologia , Regeneração , Propriedades de SuperfícieRESUMO
SRY-related high-mobility-group box 9 (Sox9) gene is a cartilage-specific transcription factor that plays essential roles in chondrocyte differentiation and cartilage formation. The aim of this study was to investigate the feasibility of genetic delivery of Sox9 to enhance chondrogenic differentiation of human umbilical cord blood-derived mesenchymal stem cells (hUC-MSCs). After they were isolated from human umbilical cord blood within 24 h after delivery of neonates, hUC-MSCs were untreated or transfected with a human Sox9-expressing plasmid or an empty vector. The cells were assessed for morphology and chondrogenic differentiation. The isolated cells with a fibroblast-like morphology in monolayer culture were positive for the MSC markers CD44, CD105, CD73, and CD90, but negative for the differentiation markers CD34, CD45, CD19, CD14, or major histocompatibility complex class II. Sox9 overexpression induced accumulation of sulfated proteoglycans, without altering the cellular morphology. Immunocytochemistry demonstrated that genetic delivery of Sox9 markedly enhanced the expression of aggrecan and type II collagen in hUC-MSCs compared with empty vector-transfected counterparts. Reverse transcription-polymerase chain reaction analysis further confirmed the elevation of aggrecan and type II collagen at the mRNA level in Sox9-transfected cells. Taken together, short-term Sox9 overexpression facilitates chondrogenesis of hUC-MSCs and may thus have potential implications in cartilage tissue engineering.
Assuntos
Humanos , Diferenciação Celular/genética , Condrogênese/genética , Sangue Fetal/citologia , Células-Tronco Mesenquimais/citologia , Fatores de Transcrição SOX9/genética , Agrecanas/biossíntese , Western Blotting , Cartilagem/metabolismo , Proliferação de Células/genética , Condrócitos/metabolismo , Colágeno Tipo II/biossíntese , Citometria de Fluxo , Proteínas de Fluorescência Verde , Regulação da Expressão Gênica/fisiologia , Células Endoteliais da Veia Umbilical Humana/citologia , Imuno-Histoquímica , Imunofenotipagem , Cultura Primária de Células , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Engenharia Tecidual , TransfecçãoRESUMO
SRY-related high-mobility-group box 9 (Sox9) gene is a cartilage-specific transcription factor that plays essential roles in chondrocyte differentiation and cartilage formation. The aim of this study was to investigate the feasibility of genetic delivery of Sox9 to enhance chondrogenic differentiation of human umbilical cord blood-derived mesenchymal stem cells (hUC-MSCs). After they were isolated from human umbilical cord blood within 24 h after delivery of neonates, hUC-MSCs were untreated or transfected with a human Sox9-expressing plasmid or an empty vector. The cells were assessed for morphology and chondrogenic differentiation. The isolated cells with a fibroblast-like morphology in monolayer culture were positive for the MSC markers CD44, CD105, CD73, and CD90, but negative for the differentiation markers CD34, CD45, CD19, CD14, or major histocompatibility complex class II. Sox9 overexpression induced accumulation of sulfated proteoglycans, without altering the cellular morphology. Immunocytochemistry demonstrated that genetic delivery of Sox9 markedly enhanced the expression of aggrecan and type II collagen in hUC-MSCs compared with empty vector-transfected counterparts. Reverse transcription-polymerase chain reaction analysis further confirmed the elevation of aggrecan and type II collagen at the mRNA level in Sox9-transfected cells. Taken together, short-term Sox9 overexpression facilitates chondrogenesis of hUC-MSCs and may thus have potential implications in cartilage tissue engineering.
Assuntos
Diferenciação Celular/genética , Condrogênese/genética , Sangue Fetal/citologia , Células-Tronco Mesenquimais/citologia , Fatores de Transcrição SOX9/genética , Agrecanas/biossíntese , Western Blotting , Cartilagem/metabolismo , Proliferação de Células/genética , Condrócitos/metabolismo , Colágeno Tipo II/biossíntese , Citometria de Fluxo , Regulação da Expressão Gênica/fisiologia , Proteínas de Fluorescência Verde , Células Endoteliais da Veia Umbilical Humana/citologia , Humanos , Imuno-Histoquímica , Imunofenotipagem , Cultura Primária de Células , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Engenharia Tecidual , TransfecçãoRESUMO
Typically, production of induced pluripotent stem cells requires direct contact with feeder cells. However, once the stem cells have reached the appropriate maturation point, it is difficult to separate them from feeder cells, which must be irradiated with γ-rays or treated with the antibiotic mitomycin-C. We used a microporous poly-membrane-based indirect contact co-culture system with mouse embryonic fibroblasts to induce mouse pluripotent stem cells without radiation or antibiotics. We found that induced pluripotent stem cells induced by this co-culture method had a reprogramming efficiency and time similar to those induced using traditional methods. Furthermore, strongly expressed pluripotent markers showed a normal karyotype and formation and contained all three germ layers in a teratoma.
Assuntos
Células-Tronco Embrionárias/fisiologia , Células-Tronco Pluripotentes Induzidas/fisiologia , Animais , Antígenos de Diferenciação/metabolismo , Diferenciação Celular , Técnicas de Cocultura/instrumentação , Técnicas de Cocultura/métodos , Células Alimentadoras , Fibroblastos/fisiologia , Proteínas de Homeodomínio/metabolismo , Células-Tronco Pluripotentes Induzidas/transplante , Cariótipo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos SCID , Proteína Homeobox Nanog , Teratoma/patologia , Fatores de Transcrição/metabolismoRESUMO
Intrathymic injection is a common technique used for research concerning immunotolerance induction, gene therapy and T cell development in mice. Traditionally used protocols involve major surgery that exposes the thoracic cavity, which results in injury to the mice and increased risk of poor recovery and postsurgical complications such as infection. We introduce a simplified intrathymic injection technique that does not expose the thoracic cavity and virtually eliminates pain, distress and postoperative complications while maintaining high injection efficiency. The technique is suitable for both adult and neonatal mice.
Assuntos
Injeções/métodos , Timo/anatomia & histologia , Animais , Camundongos , Camundongos Endogâmicos C57BL , Agulhas , SeringasRESUMO
The direct sequencing of the Kit cDNA obtained from mutant mice was used to reveal the molecular nature of the W(-3Bao) ENU-induced mutation. There was a T to A transversion at the 441st nucleotide in the W(-3Bao) open reading frame (ORF), which introduced a pre-mature termination codon at residue 147. The gross embryonic development, hematopoiesis and spermatogenesis were examined in the mutant mice. There was no visible difference among the W(-3Bao/+), W(-3Bao/3Bao) and wild type embryos before embryonic day 12.5. W(-3Bao/3Bao) embryos appeared pale after E14.5 and dwarf after E16.5. An extremely low level of hematochrome and large red blood cells were found in W(-3Bao/3Bao) 18.5 days old embryos, leading to the stillbirth of the homozygotes. In 18.5 days old embryos the spermatogonia of W(-3Bao/3Bao) embryos did not migrate to the contorted seminiferous tubules properly, but instead were found in the interstitial tissue. The spermatogonia of W(-3Bao/+) or W(+/+) mice were present in both the interstitial tissue and contorted seminiferous tubules. In the adult male hetereozygotes, there are contorted seminiferous tubules with no spermatogonia, suggesting that the migration defect was dominant. In female W(-3Bao/3Bao) ovaries, primordial follicles were absent while primordial follicles appeared clearly in the ovaries of W(-3Bao/+) or W(+/+) mice. With a nonsense mutation in the Kit gene, W(-3Bao/+) mice show white spotting and an abnormal development of the contorted seminiferous tubules and W(-3Bao/3Bao) mice are stillborn due to severe macrocytic anemia, and have abnormal genital glands in both the male and female.
Assuntos
Mutação , Proteínas Proto-Oncogênicas c-kit/genética , Animais , Camundongos , FenótipoRESUMO
BACKGROUND: Discussions about medical errors facilitate professional learning for physicians and may provide emotional support after an error, but little is known about physicians' attitudes and practices regarding error discussions with colleagues. METHODS: Survey of faculty and resident physicians in generalist specialties in Midwest, Mid-Atlantic and Northeast regions of the US to investigate attitudes and practices regarding error discussions, likelihood of discussing hypothetical errors, experience role-modelling error discussions and demographic variables. RESULTS: Responses were received from 338 participants (response rate = 74%). In all, 73% of respondents indicated they usually discuss their mistakes with colleagues, 70% believed discussing mistakes strengthens professional relationships and 89% knew at least one colleague who would be a supportive listener. Motivations for error discussions included wanting to learn whether a colleague would have made the same decision (91%), wanting colleagues to learn from the mistake (80%) and wanting to receive support (79%). Given hypothetical scenarios, most respondents indicated they would likely discuss an error resulting in no harm (77%), minor harm (87%) or major harm (94%). Fifty-seven percent of physicians had tried to serve as a role model by discussing an error and role-modelling was more likely among those who had previously observed an error discussion (OR 4.17, CI 2.34 to 7.42). CONCLUSIONS: Most generalist physicians in teaching hospitals report that they usually discuss their errors with colleagues, and more than half have tried to role-model discussions. However, a significant number of these physicians report that they do not usually discuss their errors and some do not know colleagues who would be supportive listeners.
Assuntos
Atitude do Pessoal de Saúde , Docentes de Medicina , Internato e Residência , Erros Médicos/psicologia , Revelação da Verdade/ética , Competência Clínica , Feminino , Humanos , Masculino , Erros Médicos/ética , Estatística como Assunto , Inquéritos e QuestionáriosRESUMO
The influence of membrane lipid composition on the molecular activity of a major membrane protein (the sodium pump) was examined as a test of the membrane pacemaker theory of metabolism. Microsomal membranes from the kidneys of cattle (Bos taurus) and crocodiles (Crocodylus porosus) were found to possess similar sodium pump concentrations, but cattle membranes showed a four- to fivefold higher enzyme (Na(+)-K(+)-ATPase) activity when measured at 37 degrees C. The molecular activity of the sodium pumps (ATP/min) from both species was fully recoverable when delipidated pumps were reconstituted with membrane from the original source (same species). The results of experiments involving species membrane crossovers showed cattle sodium pump molecular activity to progressively decrease from 3,245 to 1,953 (P < 0.005) to 1,031 (P < 0.003) ATP/min when subjected to two cycles of delipidation and reconstitution with crocodile membrane as a lipid source. In contrast, the molecular activity of crocodile sodium pumps progressively increased from 729 to 908 (P < 0.01) to 1,476 (P = 0.01) ATP/min when subjected to two cycles of delipidation and reconstitution with cattle membrane as a lipid source. The lipid composition of the two membrane preparations showed similar levels of saturated ( approximately 31-34%) and monounsaturated ( approximately 23-25%) fatty acids. Cattle membrane had fourfold more n-3 polyunsaturated fatty acids (11.2 vs. 2.9%) but had a reduced n-6 polyunsaturate content (29 vs. 43%). The results support the membrane pacemaker theory of metabolism and suggest membrane lipids and their polyunsaturates play a significant role in determining the molecular activity of the sodium pump.
Assuntos
Jacarés e Crocodilos/metabolismo , Bovinos/metabolismo , Lipídeos de Membrana/metabolismo , Modelos Biológicos , ATPase Trocadora de Sódio-Potássio/metabolismo , Animais , Ácidos Graxos Ômega-3/metabolismo , Ácidos Graxos Ômega-6/metabolismo , Membranas Intracelulares/metabolismo , Rim/metabolismo , Microssomos/metabolismoRESUMO
The activity of the ubiquitous Na(+)/K(+)-ATPase represents a substantial portion of the resting metabolic activity of cells, and the molecular activity of this enzyme from tissues of different vertebrates can vary several-fold. Microsomes were prepared from the kidney and brain of the rat (Rattus norvegicus) and the cane toad (Bufo marinus), and Na(+)/K(+)-ATPase molecular activity was determined. The membrane lipids surrounding this enzyme were isolated and phospholipids prepared. 'Surface pressure/area' isotherms were measured in monolayers for both membrane lipids and phospholipids using classic Langmuir trough techniques. Microsomal lipid composition was also measured. Whilst significant correlations were observed between membrane composition and Na(+)/K(+)-ATPase molecular activity, the strongest correlations were found between the molecular activity and parameters describing the packing of the surrounding membrane lipids and phospholipids. The influence of membrane lipid composition, especially membrane acyl composition, on the activity of a membrane protein mediated by physical properties of the lipids may represent a fundamental principle applicable to other membrane proteins.
Assuntos
Lipídeos de Membrana/análise , ATPase Trocadora de Sódio-Potássio/metabolismo , Animais , Encéfalo/ultraestrutura , Bufo marinus , Ácidos Graxos/análise , Rim/ultraestrutura , Cinética , Microssomos/química , Microssomos/enzimologia , Fosfolipídeos/análise , Ratos , ATPase Trocadora de Sódio-Potássio/análise , Especificidade da EspécieRESUMO
A 32-year-old recent Russian immigrant, mother of a 20-month-old son, presented with right hip pain. She had a history of peptic ulcer disease and a positive Helicobacter pylori serology. Her pain was not relieved by analgesics. Spine and pelvic films were unremarkable. A bone scan was consistent with metastatic disease. She underwent several diagnostic tests including computed tomography of the chest and abdomen, magnetic resonance imaging of the spine, mammogram, and breast ultrasound. A bone marrow biopsy revealed adenocarcinoma, primary site unknown. An upper endoscopy performed eight weeks after her initial presentation showed an ulcerating gastric carcinoma. She was treated with chemotherapy but died two months after diagnosis. Our patient had an uncommon presentation of a common disease. Recognizing her country of origin, and other risk factors, may have facilitated an earlier diagnosis.
Assuntos
Adenocarcinoma/diagnóstico , Artralgia/etiologia , Articulação do Quadril , Neoplasias Gástricas/diagnóstico , Adenocarcinoma/patologia , Adenocarcinoma/terapia , Adulto , Diagnóstico Diferencial , Evolução Fatal , Feminino , Humanos , Anamnese , Neoplasias Gástricas/patologia , Neoplasias Gástricas/terapiaRESUMO
Muscle membrane fatty acid (FA) composition is linked to insulin action. The aims of this study were to compare the FA composition of muscle and erythrocyte membrane phospholipid in young children; to investigate the effect of diet on these lipid compositions; and to investigate differential incorporation of FA into muscle, erythrocyte and adipose tissue membrane phospholipid, and adipose tissue triglyceride. Skeletal muscle biopsies and fasting blood samples were taken from 61 normally nourished children (45 males and 16 females), less than 2 yr old (means +/- SE, 0.80 +/- 0.06 yr), undergoing elective surgery. Adipose tissue samples were taken from 15 children. There were significant positive correlations between muscle and erythrocyte docosahexaenoic acid (DHA) (r = 0.44, P < 0.0001), total n-3 polyunsaturated fatty acids (PUFA) (r = 0.39, P = 0.002), and the n-6/n-3 PUFA ratio (r = 0.39, P = 0.002). Adipose tissue triglyceride had lower levels of long-chain PUFA, especially DHA, than muscle and erythrocytes (0.46 +/- 0.18% vs. 2.44 +/- 0.26% and 3.17 +/- 0.27%). Breast-fed infants had higher levels of DHA than an age-matched group of formula-fed infants in both muscle (3.91 +/- 0.21% vs. 1.94 +/- 0.18%) and erythrocytes (3.81 +/- 0.40% vs. 2.65 +/- 0.23%). The results of this study show that (i) erythrocyte FA composition is a reasonable index of muscle DHA, total n-3 PUFA, and the n-6/n-3 PUFA ratio; (ii) breast feeding has a potent effect on the FA composition of all these tissues; and (iii) there is a wide range in long-chain PUFA levels in muscle, erythrocytes, and adipose tissue.
Assuntos
Aleitamento Materno , Membrana Eritrocítica/química , Ácidos Graxos/análise , Alimentos Infantis , Músculo Esquelético/química , Fosfolipídeos/análise , Tecido Adiposo/química , Membrana Celular/química , Ácidos Docosa-Hexaenoicos/análise , Ácidos Graxos/sangue , Ácidos Graxos Ômega-3/análise , Ácidos Graxos Ômega-6 , Ácidos Graxos Insaturados/análise , Feminino , Humanos , Lactente , Masculino , Triglicerídeos/análiseRESUMO
The major body organs of mammals have sodium pumps that turn over energy (ATP) three to four times faster than those of ectotherms, at the same temperature. To examine if membranes play a role in these differences in molecular activity, membrane cross-over experiments were performed using two representative species, Rattus norvegicus and Bufo marinus. Microsomal membrane of kidney and brain displayed characteristic molecular activity differences (three- to four-fold) between the species. These molecular activity differences could be removed by delipidation. Pre-existing molecular activities and differences could be restored when reconstituted with original membrane. Using the same reconstitution method, species membrane cross-over experiments resulted in toad sodium pumps in rat membrane significantly increasing (approximately 30-40%) and rat sodium pumps in toad membrane significantly decreasing (approximately 40%) activities in both kidney and brain. Analysis of membrane composition showed reduced cholesterol content and differences in the fatty acids of phospholipids with higher overall unsaturation in the mammal. The scope for membranes to determine protein performance and its broader implications for metabolism are discussed.
Assuntos
ATPase Trocadora de Sódio-Potássio/metabolismo , Animais , Encéfalo/enzimologia , Encéfalo/metabolismo , Bufo marinus , Colesterol/metabolismo , Ácidos Graxos/metabolismo , Membranas Intracelulares/enzimologia , Membranas Intracelulares/metabolismo , Rim/enzimologia , Rim/metabolismo , Masculino , Lipídeos de Membrana/metabolismo , Microssomos/enzimologia , Microssomos/metabolismo , Fosfolipídeos/metabolismo , Ratos , Ratos Sprague-Dawley , Especificidade da EspécieRESUMO
The basal promoter of the human hsp70 gene is predominantly controlled by a CCAAT element at position -70 relative to the transcriptional initiation site. We report the isolation of a novel cDNA clone encoding a 114-kDa polypeptide that binds to the CCAAT element of the hsp70 promoter. Expression of this CCAAT-binding factor (CBF) cDNA activated transcription from cotransfected hsp70 promoter-reporter gene constructs in a CCAAT-dependent manner. CCAAT-binding factor shows no homology to the previously identified human CCAAT transcription factor or rat CCAAT/enhancer-binding protein.