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BACKGROUND: Eribulin mesylate is a novel, nontaxane, microtubule dynamics inhibitor. In this study, we assessed the efficacy and safety of eribulin versus eribulin plus the oral small-molecule tyrosine kinase inhibitor anlotinib in patients with locally recurrent or metastatic breast cancer. PATIENTS AND METHODS: In this single-center, open-label, phase II clinical study (NCT05206656) conducted in a Chinese hospital, patients with human epidermal growth factor receptor 2 (HER2)-negative, locally recurrent or metastatic breast cancer previously treated with anthracycline- or taxane-based chemotherapy were randomized (1 : 1) to receive eribulin alone or in combination with anlotinib. The primary efficacy endpoint was investigator-assessed progression-free survival (PFS). RESULTS: From June 2020 to April 2022, a total of 80 patients were randomly assigned to either eribulin monotherapy or eribulin plus anlotinib combination therapy, with 40 patients in each group. The data cut-off was 10 August 2022. The median PFS was 3.5 months [95% confidence interval (CI) 2.8-5.5 months] for eribulin and 5.1 months (95% CI 4.5-6.9 months) for eribulin plus anlotinib (hazard ratio = 0.56, 95% CI 0.32-0.98; P = 0.04). The objective response rates were 32.5% versus 52.5% (P = 0.07), respectively, and disease control rates were 67.5% versus 92.5% (P = 0.01), respectively. Patients <50 years of age, with an Eastern Cooperative Oncology Group performance status score of 0, visceral metastasis, number of treatment lines of four or more, hormone receptor negative (triple-negative), and HER2 low expression appeared to benefit more from combined treatment. The most common adverse events in both groups were leukopenia (n = 28, 70.0%, patients in the eribulin monotherapy group versus n = 35, 87.5%, patients in the combination therapy group), aspartate aminotransferase elevations (n = 28, 70.0%, versus n = 35, 87.5%), neutropenia (n = 25, 62.5%, versus n = 31, 77.5%), and alanine aminotransferase elevations (n = 25, 62.5%, versus n = 30, 75.0%). CONCLUSION: Eribulin plus anlotinib can be considered an alternative treatment option for HER2-negative locally advanced or metastatic breast cancer.
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Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/patologia , Furanos/efeitos adversos , Cetonas/efeitos adversosRESUMO
PURPOSE: This single-center retrospective study aimed to observe survival and prognosis of elderly patients with esophageal cancer receiving radical radiotherapy combined with S1 chemotherapy, and to preliminarily explore whether hematologic indicators or inflammatory indicators before radiotherapy are prognostic factors. MATERIAL AND METHODS: We retrospectively collected data of 80 elderly patients with esophageal cancer who had received radical concurrent chemoradiotherapy from January 2015 to July 2018. The patients were older than 70 years. Radiation therapy was delivered with intensity-modulated irradiation therapy (IMRT) or volumetric modulated arc therapy (VMAT), while the chemotherapy regimen was S1 alone. Toxicities were evaluated in accordance with the criteria of the Radiation Therapy Oncology Group. Baseline hematologic basic nutritional indicators, such as hemoglobin (HGB), albumin (ALB), and prealbumin (PAB), along with inflammatory indicators, such as the ratio of neutrophils to lymphocytes (NLR), the ratio of platelets to lymphocytes (PLR), were collected to preliminarily analyze their relationship with progression and survival. RESULTS: The median follow-up time was 39 months (range 30-65 months). The median overall survival and progression-free survival times were 24 and 17 months, respectively. The 1-, 2-, and 3-year overall survival rates were 76.5%, 48.1%, and 31.3%, respectively. The 1-, 2-, and 3-year progression-free survival rates were 57.5%, 37.8%, and 29.4%, respectively. T stage, clinical staging, and lesion region were independent prognostic factors for OS. No significant associations with prognosis were observed either for baseline hematologic or for inflammatory indicators (all P>0.05). The rates of esophagitis (grade 2 and above) and hematologic toxicity were 60% and 45%, respectively. CONCLUSION: Oral S-1 combined with definitive concurrent radiotherapy for elderly patients with esophageal cancer has a significant survival benefit. The toxicities are well tolerated. It seems that prognosis does not correlate with baseline hematologic nutritional indicators and inflammatory indicators.
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Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Esofagite , Radioterapia de Intensidade Modulada , Humanos , Idoso , Carcinoma de Células Escamosas do Esôfago/terapia , Estudos Retrospectivos , Quimiorradioterapia/efeitos adversos , Radioterapia de Intensidade Modulada/efeitos adversos , Análise de Sobrevida , Esofagite/etiologia , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversosRESUMO
Objective: Based on the data of Global Burden of Disease 2019 data, to analyze the past, current, and future burden of disability-adjusted life years (DALYs) in China and compare with the international status. Methods: The total number of DALYs, age-standardized DALY rate, and the composition of different subgroups were extracted and described to analyze the time trend in 2000-2019 and the current situation in 2019 for Chinese female breast cancer. The burden of DALYs in 2050 was predicted by Joinpoint using average annual percent change (AAPC). Results: In 2000-2019, the ranking of DALYs caused by female breast cancer in China rose from the fourth to the second in all female cancers. The total DALYs increased by 48.4%, of which the years lived with disability increased from 4.8% to 8.8%. The age-standardized DALY rate only slightly decreased (AAPC=-0.3%; which increased during 2016-2019, AAPC=1.6%). In 2019, the age-standardized DALY rate for breast cancer in China was 278.0/100 000. The DALYs were 2.88 million (accounting for 14.2% of the global burden and 12.1% of all female cancers burden in China), 26.5% of which attributed known risk factors (overweight and obesity were the largest: 0.34 million DALYs, but some common breast cancer risk factors were not available on the platform, such as menstruation and fertility). In 2050, the prediction suggests that the total DALYs caused by female breast cancer in China will reach 3.80 million person-years-5.16 million person-years, increasing 32.1%-79.4% over 2019. From 2000 to 2019, the peak age of DALYs and DALY rate became older, and the DALYs among females aged 65 years and above increased faster than those younger than 65 years (AAPC were 4.8% and 1.3%, respectively). In 2019, females aged 45-74 (the starting age recommended by local guidelines for breast cancer screening) contributed 74.3% of the total DALYs. Conclusions: Over the past 20 years, the age-standardized DALY rate for breast cancer in female populations in China has not changed obviously. Without the continuous expansion of effective intervention and population aging, the burden of DALYs for female breast cancer in China will increase. DALYs for breast cancer attributed leading risk factors were still limited.
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Neoplasias da Mama , Pessoas com Deficiência , Idoso , Neoplasias da Mama/epidemiologia , China/epidemiologia , Efeitos Psicossociais da Doença , Anos de Vida Ajustados por Deficiência , Feminino , Carga Global da Doença , Humanos , Anos de Vida Ajustados por Qualidade de VidaRESUMO
Lesion mimic mutants spontaneously produce disease spots in the absence of biotic or abiotic stresses. Analyzing lesion mimic mutants' sheds light on the mechanisms underlying programmed cell death and defense-related responses in plants. Here, we isolated and characterized the rice (Oryza sativa) spotted leaf 36 (spl36) mutant, which was identified from an ethyl methanesulfonate-mutagenized japonica cultivar Yundao population. spl36 displayed spontaneous cell death and enhanced resistance to rice bacterial pathogens. Gene expression analysis suggested that spl36 functions in the disease response by upregulating the expression of defense-related genes. Physiological and biochemical experiments indicated that more cell death occurred in spl36 than the wild type and that plant growth and development were affected in this mutant. We isolated SPL36 by map-based cloning. A single base substitution was detected in spl36, which results in a cysteine-to-arginine substitution in SPL36. SPL36 is predicted to encode a receptor-like protein kinase containing leucine-rich domains that may be involved in stress responses in rice. spl36 was more sensitive to salt stress than the wild type, suggesting that SPL36 also negatively regulates the salt-stress response. These findings suggest that SPL36 regulates the disease resistance response in rice by affecting the expression of defense- and stress-related genes.
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Catalysts with a single atom site allow highly tuning of the activity, stability, and reactivity of heterogeneous catalysts. Therefore, atomistic understanding of the pertinent mechanism is essential to simultaneously boost the intrinsic activity, site density, electron transport, and stability. Here, we report that atomically dispersed nickel (Ni) in zincblende cadmium-zinc sulfide quantum dots (ZCS QDs) delivers an efficient and durable photocatalytic performance for water splitting under sunlight. The finely tuned Ni atoms dispersed in ZCS QDs exhibit an ultrahigh photocatalytic H2 production activity of 18.87 mmol hour-1 g-1. It could be ascribed to the favorable surface engineering to achieve highly active sites of monovalent Ni(I) and the surface heterojunctions to reinforce the carrier separation owing to the suitable energy band structures, built-in electric field, and optimized surface H2 adsorption thermodynamics. This work demonstrates a synergistic regulation of the physicochemical properties of QDs for high-efficiency photocatalytic H2 production.
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OBJECTIVE: Metabolic disorders and inflammation of chondrocytes are major pathological changes in aging cells and osteoarthritis (OA). Recent studies demonstrated age-related mitochondrial dysfunction may be a key contributing factor in the development of OA. Mitofusin 2 (MFN2) is a key regulator of mitochondrial fusion, cell metabolism, autophagy and apoptosis. This study was performed to ascertain whether MFN2 was involved in the aging of chondrocytes and OA. METHODS: Metabolic measurements were taken in rat chondrocytes between different ages (3-week, 5-month, 12-month). MFN2 activity was detected in both human and rat chondrocytes during aging and OA. Then, knockdown of MFN2 with small interfering RNA (siRNA) was performed to confirm whether MFN2 contributes to metabolic changes. Lentiviruses were used to establish MFN2-overexpression/knockdown OA models both in vivo and in vitro to confirm whether MFN2 contributes to OA progress. Further, regulatory mechanism of MFN2 was assessed and interaction between MFN2 and PARKIN was performed. RESULTS: A metabolic shift to mitochondrial respiration was confirmed in rat chondrocytes during aging. MFN2 expression was elevated in both human and rat chondrocytes during aging and OA. Knockdown of MFN2 with siRNA reversed the age-related metabolic changes in rat chondrocytes. Overexpression of MFN2 exacerbated inflammation and OA progress, while knockdown of MFN2 ameliorated inflammation and OA progress. Further, MFN2 could be ubiquitinated by PARKIN, declined PARKIN expression during aging and OA might result in elevated MFN2 expression. CONCLUSIONS: Elevated MFN2 contributes to metabolic changes and inflammation during aging of rat chondrocytes and osteoarthritis.
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Envelhecimento/metabolismo , Condrócitos/metabolismo , GTP Fosfo-Hidrolases/metabolismo , Proteínas Mitocondriais/metabolismo , Osteoartrite/metabolismo , Trifosfato de Adenosina/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/genética , Animais , Apoptose/genética , Autofagia/genética , Estudos de Casos e Controles , Respiração Celular , Senescência Celular , Modelos Animais de Doenças , Feminino , GTP Fosfo-Hidrolases/genética , Técnicas de Silenciamento de Genes , Glucose/metabolismo , Humanos , Inflamação , Masculino , Meniscos Tibiais/cirurgia , Pessoa de Meia-Idade , Mitocôndrias/metabolismo , Dinâmica Mitocondrial/genética , Proteínas Mitocondriais/genética , Osteoartrite/genética , Consumo de Oxigênio , Ratos , Espécies Reativas de Oxigênio/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Adulto JovemRESUMO
Objective: The aim of this retrospective study was to evaluate the prognostic significance of pretreatment Neutrophil-to-Lymphocyte Ratio(NLR) in locally advanced non-small cell lung cancer(NSCLC) patients treated with thoracic radiotherapy. Methods: We retrospectively analyze 420 patients who received thoracic radiotherapy alone, sequential chemoraiotherapy or concurrent chemoradiotherapy for locally advanced stage NSCLC from January 2007 to December 2010 of our hospital. The patients were divided into two groups (high NLR group and low NLR group) with appropriate cutoff point using the receiver operating characteristic (ROC) curve method. The survival curve was established by Kaplan-Meier method. The Log-rank test was used to compare the survival of the two NLR groups and the multivariate analysis was carried out by Cox regression model. Results: Among the 420 patients, 99 received radiotherapy alone, 139 received sequential chemoradiotherapy and 182 received concurrent chemoradiotherapy. 345 patients died and 75 were still alive. The median follow-up time was 5.2 years and the median overall survival was 22 months. The cut-off value of pretreatment NLR was 2.1. The 5-year PFS and OS rates in high NLR group and low NLR group were 10.6% vs 15.7% (P=0.033) and 15.5% vs 22.7% (P=0.012). Multivariate analysis confirmed that pretreatment NLR (hazard ratio 1.06, P=0.041) was independent prognostic factor of OS. Conclusions: Our study revealed that the pretreatment NLR is the independent prognostic factor of OS in patients with locally advanced stage NSCLC treated with thoracic radiotherapy. However, NLR is still greatly influenced by patient's condition and treatment which needs further research.
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Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Quimiorradioterapia/métodos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/radioterapia , Linfócitos , Neutrófilos , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Humanos , Estimativa de Kaplan-Meier , Contagem de Leucócitos , Neoplasias Pulmonares/mortalidade , Contagem de Linfócitos , Subpopulações de Linfócitos , Análise Multivariada , Prognóstico , Modelos de Riscos Proporcionais , Curva ROC , Estudos RetrospectivosRESUMO
Tumor necrosis factor receptor-associated factor 6 (TRAF6) is a crucial adaptor molecule of the interleukin-1 receptor/Toll-like receptor (IL-1/TLR) superfamily, which can trigger downstream signaling cascades involved in innate immunity. The function of TRAF6 has been clarified in mammals but is poorly understood in chicken. In our study, we investigated TRAF6 function in birds, particularly in chicken innate immune responses, by cloning and characterizing chicken TRAF6 (chTRAF6). The full-length coding sequence of chTRAF6 comprised 1638 bp and encoded a 545-amino acid protein, which shares high sequence similarity with TRAF6 of other species and consists of four structurally conserved domains. Quantitative real-time polymerase chain reaction revealed that chTRAF6 was widely expressed in all tested tissues and its expression was induced in chicken embryo fibroblast cells treated with poly(I:C) and poly(dA:dT). Increased expression of chTRAF6 was observed both in vitro and in vivo following infection with Newcastle disease virus in chickens. Taken together, these results suggest that chTRAF6 plays a vital role in host defense against viral infection in chicken.
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Proteínas Aviárias/genética , Galinhas/genética , Fator 6 Associado a Receptor de TNF/genética , Animais , Proteínas Aviárias/química , Proteínas Aviárias/metabolismo , Galinhas/imunologia , Galinhas/metabolismo , Resistência à Doença/genética , Resistência à Doença/imunologia , Expressão Gênica , Imunidade Inata/genética , Domínios e Motivos de Interação entre Proteínas , Transdução de Sinais , Fator 6 Associado a Receptor de TNF/química , Fator 6 Associado a Receptor de TNF/metabolismoRESUMO
OBJECTIVE: Dexmedetomidine, a highly selective α2-adrenergic receptor agonist with sedative and analgesic properties, is used as an anesthetic adjunct. We determined the effects of different dexmedetomidine doses on the median effective concentration (EC50) of propofol and bispectral index (BIS) values during anesthesia induction. PATIENTS AND METHODS: This randomized, prospective, case-control clinical trial involved 120 patients (56 women; physical status, American Society of Anesthesiologists grades I or II) scheduled to undergo surgery requiring general anesthesia from July 15th, 2014 to June 15th, 2015. The patients were divided into groups of 30 and received dexmedetomidine (0.5 µg/kg, group L; 0.75 µg/kg, group M; 1 µg/kg, group H) with propofol for loss of consciousness or propofol only (control group, group C). EC50, BIS, hemodynamics, and side effects were assessed. RESULTS: The EC50 of propofol was significantly lower in the dexmedetomidine groups than in group C, and decreased with increasing dexmedetomidine dose (p < 0.05). BIS values significantly decreased after 2 min of dexmedetomidine infusion in all dexmedetomidine groups; the values at 8 and 10 min were lower in the dexmedetomidine groups than in group C. The heart rate was lower in the dexmedetomidine groups than in group C. The incidence of bradycardia at loss of consciousness increased with increasing dexmedetomidine dose. CONCLUSIONS: Dexmedetomidine significantly and dose-dependently reduced the EC50 of propofol and BIS values during anesthesia induction. A loading dexmedetomidine dose of 0.5 µg/kg significantly reduced the EC50 of propofol and BIS value, and was associated with a lower incidence of bradycardia than higher doses.
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Agonistas de Receptores Adrenérgicos alfa 2/farmacologia , Dexmedetomidina/farmacologia , Propofol/administração & dosagem , Propofol/farmacologia , Anestésicos Intravenosos , Monitores de Consciência , Relação Dose-Resposta a Droga , Interações Medicamentosas , Feminino , Humanos , Hipnóticos e Sedativos , Masculino , Estudos ProspectivosRESUMO
Hepatic oval cells (HOCs) are recognized as facultative liver progenitor cells that play a role in liver regeneration after acute liver injury. Here, we investigated the in vitro proliferation and differentiation characteristics of HOCs in order to explore their potential capacity for intrahepatic transplantation. Clusters or scattered HOCs were detected in the portal area and interlobular bile duct in the liver of rats subjected to the modified 2-acetylaminofluorene and partial hepatectomy method. Isolated HOCs were positive for c-kit and CD90 staining (99.8% and 88.8%, respectively), and negative for CD34 staining (3.6%) as shown by immunostaining and flow cytometric analysis. In addition, HOCs could be differentiated into hepatocytes and bile duct epithelial cells after leukemia inhibitory factor deprivation. A two-cuff technique was used for orthotopic liver transplantation, and HOCs were subsequently transplanted into recipients. Biochemical indicators of liver function were assessed 4 weeks after transplantation. HOC transplantation significantly prolonged the median survival time and improved the liver function of rats receiving HOCs compared to controls (P = 0.003, Student t-test). Administration of HOCs to rats also receiving liver transplantation significantly reduced acute allograft rejection compared to control liver transplant rats 3 weeks following transplantation (rejection activity index score: control = 6.3 ± 0.9; HOC = 3.5 ± 1.5; P = 0.005). These results indicate that HOCs may be useful in therapeutic liver regeneration after orthotopic liver transplantation.
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Diferenciação Celular/fisiologia , Proliferação de Células , Transplante de Células/métodos , Hepatócitos/citologia , Transplante de Fígado/métodos , Animais , Feminino , Citometria de Fluxo , Rejeição de Enxerto/diagnóstico , Hepatectomia , Imuno-Histoquímica , Fígado/anatomia & histologia , Fígado/cirurgia , Masculino , Cultura Primária de Células , Ratos , Ratos Endogâmicos Lew , Reação em Cadeia da Polimerase em Tempo Real/métodos , Taxa de SobrevidaRESUMO
Hepatic oval cells (HOCs) are recognized as facultative liver progenitor cells that play a role in liver regeneration after acute liver injury. Here, we investigated the in vitro proliferation and differentiation characteristics of HOCs in order to explore their potential capacity for intrahepatic transplantation. Clusters or scattered HOCs were detected in the portal area and interlobular bile duct in the liver of rats subjected to the modified 2-acetylaminofluorene and partial hepatectomy method. Isolated HOCs were positive for c-kit and CD90 staining (99.8% and 88.8%, respectively), and negative for CD34 staining (3.6%) as shown by immunostaining and flow cytometric analysis. In addition, HOCs could be differentiated into hepatocytes and bile duct epithelial cells after leukemia inhibitory factor deprivation. A two-cuff technique was used for orthotopic liver transplantation, and HOCs were subsequently transplanted into recipients. Biochemical indicators of liver function were assessed 4 weeks after transplantation. HOC transplantation significantly prolonged the median survival time and improved the liver function of rats receiving HOCs compared to controls (P=0.003, Student t-test). Administration of HOCs to rats also receiving liver transplantation significantly reduced acute allograft rejection compared to control liver transplant rats 3 weeks following transplantation (rejection activity index score: control=6.3±0.9; HOC=3.5±1.5; P=0.005). These results indicate that HOCs may be useful in therapeutic liver regeneration after orthotopic liver transplantation.
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Animais , Feminino , Masculino , Ratos , Proliferação de Células , Diferenciação Celular/fisiologia , Transplante de Células/métodos , Hepatócitos/citologia , Transplante de Fígado/métodos , Citometria de Fluxo , Rejeição de Enxerto/diagnóstico , Hepatectomia , Imuno-Histoquímica , Fígado/anatomia & histologia , Fígado/cirurgia , Cultura Primária de Células , Ratos Endogâmicos Lew , Reação em Cadeia da Polimerase em Tempo Real/métodos , Taxa de SobrevidaRESUMO
UNLABELLED: BACKGROUND; Heavy ions represent the best tool for external radiotherapy (RT) of inoperable tumours. Heavy ion RT has been used in the treatment of various tumours, especially for radioresistant tumours mediated by hypoxia, localized near organs at risk. Most of these treatments are concentrated in deep-seated tumours such as those of the brain, head, lung, liver, rectum and urogenital organs, and treatment of skin carcinomas is limited. OBJECTIVES: To evaluate the outcome and toxicity after carbon ion RT for skin carcinomas at the Heavy Ion Research Facility in Lanzhou, China. METHODS: Between November 2006 and March 2009, 45 patients with skin carcinoma [squamous cell carcinoma (SCC) (n = 16), basal cell carcinoma (BCC) (n = 12), malignant melanoma (MM) (n = 7), Bowen disease (n = 8) and Paget disease (n = 2)] were treated with carbon ion RT within a clinical Phase I trial. Patients received total doses of 60-70 GyE for SCC and BCC, 61-75 GyE for MM, 60 GyE for Bowen disease and 42·5 GyE for Paget disease, administered in 6-11 fractions over 6-11 days, with a fraction dose of 7-10 GyE. RESULTS: The mean follow-up was 24 months, range 12-36 months. The actuarial local control rates at 1 and 3 years were 90·9% and 65·5% for SCC, 91·7% and 80·2% for BCC, 85·7% and 42·9% for MM, 90% and 90% for Bowen and Paget diseases, respectively. The actuarial 1- and 3-year overall survival rates for 45 patients were 88·9% and 86%, respectively. No severe side-effects greater than Common Toxicity Criteria grade 3 have been observed. CONCLUSIONS: The results demonstrated that heavy ion RT offers high local tumour control and progression-free survival rates without significant radiation-induced toxicity for patients with skin carcinomas.
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Carbono/uso terapêutico , Radioterapia com Íons Pesados , Neoplasias Cutâneas/radioterapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Radioterapia/efeitos adversos , Resultado do TratamentoRESUMO
The aim of this study was to provide information about the morphology and topography of the recurrent laryngeal nerve (RLN), its external features and branches, as well as its relationship to the inferior thyroid artery, the inferior horn of the thyroid cartilage and the thyroid gland. The RLNs in 50 adult cadavers (100 sides) were dissected and analyzed. A communicating loop connecting one branch of the RLN to another or a twig originating from the cervical sympathetic trunk was present in 13 of 100 sides. A double left RLN appeared in 2 sides; a right non-recurrent inferior laryngeal nerve appeared in one side. All of the RLNs, including looped ones, bifurcated into laryngeal branches and extralaryngeal branches, with most of the former further dividing into the anterior and posterior branches entering the larynx. The relations of the RLN to the inferior thyroid artery, the inferior horn of the thyroid cartilage and the thyroid gland were inconstant. The information gained from this study will be of value in thyroid surgery.
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Nervo Laríngeo Recorrente/anatomia & histologia , Glândula Tireoide/irrigação sanguínea , Adulto , Artérias/anatomia & histologia , Humanos , Cartilagem Tireóidea/anatomia & histologia , Glândula Tireoide/anatomia & histologiaRESUMO
Debilitating diseases such as osteo- and rheumatoid arthritis, trauma and bone cancer can be treated by using prostheses. The wear resistance of materials for joint replacement can affect the service-quality and service-life of prostheses. Materials for joint replacement and friction and wear were briefly reviewed in this paper.
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Prótese Articular , Ligas , Cerâmica , Ligas de Cromo , Fricção , Humanos , Falha de PróteseRESUMO
The ultrastructure of the megakaryocytes in the bone marrow from 14 cases of megaloblastic anemia was studied. The commonest change observed was that the development of the nucleus lagged behind that of the cytoplasm. There were some evidences supporting the theory of ineffective thrombocytopoiesis. The mechanism of the relationship between the changes of morphology and function based on the impaired DNA synthesis and methylation due to folate and vitamin B12 deficiency were also discussed.
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Anemia Megaloblástica/patologia , Megacariócitos/ultraestrutura , Medula Óssea/patologia , HumanosRESUMO
We characterized the presence of the monooxygenase arylhydrocarbon-hydroxylase (AHH), in mouse bone marrow cells taken directly from animals and from bone marrow colony culture. Using a standard radio-isotopic assay it was found that AHH activity was present in mouse bone marrow cells and that there was demonstratable activity in preparations taken directly from differentiated erythroid and myeloid colony cultures. Murine colonies of erythroid (CFU-E) and granulocytes (CFU-GM) were grown and AHH activity determined in non-induced and 3-methylcholanthrene (3-MC) induced cultures. Addition of 3-MC to erythropoietin dependent CFU-E was found to induce AHH activity above controls in a dose dependent manner, with 75 micrograms generating a maximal effect. CFU-E taken from different incubation periods (1-4 days) revealed that AHH was maximal in 2 1/2 day cultures and thereafter declined. In contrast, maximal AHH activity was obtained from 6-7 day CFU-GM and 40 micrograms of 3-MC stimulated the activity by 88%. These results demonstrate that AHH is present in normal mouse bone marrow cells and developing hemopoietic colonies, and that induction of AHH may indicate an important role for these cytochrome P-450 monooxygenases in cell development and differentiation as well as in the metabolism of various drugs.