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1.
Artigo em Inglês | MEDLINE | ID: mdl-38453435

RESUMO

BACKGROUND: VS-505 (AP301), an acacia and ferric oxyhydroxide polymer, is a novel fiber-iron-based phosphate binder. This two-part phase 2 study evaluated the tolerability, safety, and efficacy of oral VS-505 administered three times daily with meals in treating hyperphosphatemia in chronic kidney disease (CKD) patients receiving maintenance hemodialysis (MHD). METHODS: In Part 1, patients received dose-escalated treatment with VS-505 2.25, 4.50, and 9.00 g/day for 2 weeks each, guided by serum phosphorus levels. In Part 2, patients received randomized, open-label, fixed-dosage treatment with VS-505 (1.50, 2.25, 4.50, or 6.75 g/day) or sevelamer carbonate 4.80 g/day for 6 weeks. The primary efficacy endpoint was the change in serum phosphorus. RESULTS: The study enrolled 158 patients (Part 1: 25; Part 2: 133), with 130 exposed to VS-505 in total. VS-505 was well tolerated. The most common adverse events were gastrointestinal disorders, mainly feces discolored (56%) and diarrhea (15%; generally during weeks 1‒2 of treatment). Most gastrointestinal disorders resolved without intervention, and none were serious. In Part 1, serum phosphorus significantly improved (mean change -2.0 mg/dL; 95% confidence interval -2.7, -1.4) after VS-505 dose escalation. In Part 2, serum phosphorus significantly and dose-dependently improved in all VS-505 arms, with clinically meaningful reductions with VS-505 4.50 and 6.75 g/day, and sevelamer carbonate 4.80 g/day (mean change -1.6 (-2.2, -1.0), -1.8 (-2.4, -1.2), and -1.4 (-2.2, -0.5) mg/dL, respectively). In both Parts, serum phosphorus reductions occurred within 1 week of VS-505 initiation, returning to baseline within 2 weeks of VS-505 discontinuation. CONCLUSION: VS-505, a novel phosphate binder, was well tolerated with a manageable safety profile, and effectively and dose-dependently reduced serum phosphorus in CKD patients with hyperphosphatemia receiving MHD. Clinical Trial registration number: NCT04551300.

2.
BMC Nephrol ; 24(1): 275, 2023 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-37730535

RESUMO

BACKGROUND: Good knowledge of and attitudes toward hemodialysis and its complications might be expected to promote good practices and improve adherence. This study investigated, the knowledge, attitude, and practice of patients receiving hemodialysis regarding hemodialysis and its complications. METHODS: This cross-sectional study enrolled patients with uremia who were receiving hemodialysis at the Second Affiliated Hospital of Nanjing Medical University (China) between January 9, 2023, and January 16, 2023. A questionnaire was designed that included the following dimensions: demographic/clinical information, knowledge, attitude, and practice. Correlations between knowledge, attitude, and practice scores were evaluated by Pearson correlation analysis. RESULTS: The analysis included 493 patients (305 males, 61.87%). The average knowledge, attitude, and practice score was 19.33 ± 7.07 (possible range, 0-31), 28.77 ± 3.58 (possible range, 8-40), and 43.57 ± 6.53 (possible range, 11-55) points, respectively. A higher knowledge score was associated with younger age (P < 0.001), a higher education level (P < 0.001), and not living alone (P < 0.001), while a higher practice score was associated with a shorter history of hemodialysis (P < 0.001). There were positive correlations between the knowledge and practice scores (r = 0.220, P < 0.001) and between the attitude and practice scores (r = 0.453, P < 0.001), although the knowledge and attitude scores were not significantly correlated. CONCLUSIONS: The results provide important insights into the knowledge, attitudes, and practices of patients with uremia in Nanjing (China) regarding hemodialysis and its complications. These findings may facilitate education programs to improve self-care practices in patients receiving maintenance hemodialysis in Nanjing (China).


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Uremia , Masculino , Humanos , Estudos Transversais , China/epidemiologia , Diálise Renal , Uremia/epidemiologia , Uremia/terapia
3.
Nutr Cancer ; 74(8): 2920-2929, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35225113

RESUMO

Studies regarding malnutrition in patients with nasopharyngeal carcinoma (NPC) using the Global Leadership Initiative in Malnutrition (GLIM) criteria are still limited. Our study aimed to investigate the prevalence of malnutrition using the GLIM criteria in NPC patients receiving radiotherapy and explore the relationship between pre-radiotherapy (pre-RT) malnutrition and survival. A total of 113 NPC patients were enrolled for nutritional assessment using the GLIM criteria at different radiotherapeutic time points, and related toxicities were graded. Regarding the results, 19 patients (16.8%) were malnourished before radiotherapy and 103 patients (91.2%) were malnourished at the end of radiotherapy. Among the phenotypic GLIM criteria, low fat-free muscle index (FFMI) before radiotherapy was associated with mucositis and radiodermatitis (p < 0.05). Importantly, patients with malnutrition before radiotherapy had significantly poorer 2-year progression free survival (PFS) than the patients being well-nourished (62.1% vs. 88.9%, p = 0.015). From the multivariate Cox regression model, being-well nourished before radiotherapy was the protective factor for PFS (HR: 0.27; 95%CI: 0.089-0.85; p = 0.023) and male was the risk factor for PFS (HR: 7.25; 95%CI: 1.548-34.00; p = 0.012). In conclusion, malnutrition according to the GLIM criteria is common in NPC patients undergoing radiotherapy, and pre-RT malnutrition is correlated with survival.Supplemental data for this article is available online at https://doi.org/10.1080/01635581.2022.2044059.


Assuntos
Desnutrição , Neoplasias Nasofaríngeas , Humanos , Liderança , Masculino , Desnutrição/etiologia , Carcinoma Nasofaríngeo/radioterapia , Neoplasias Nasofaríngeas/radioterapia , Avaliação Nutricional , Estado Nutricional
4.
Neurochirurgie ; 69(5): 101478, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37598621

RESUMO

OBJECTIVE: Pituitary abscess is an often misdiagnosed, rare clinical disorder. To improve diagnostic accuracy and the efficacy of surgical and antibiotic therapy for patients with pituitary abscess, herein, we retrospectively reviewed 15 patients who presented with pituitary abscesses from 2005 to 2022. DESIGN: Retrospective study. PATIENTS: Fifteen patients underwent transsphenoidal surgery and received antibiotic treatment. MEASUREMENTS: Complete details regarding medical history, clinical manifestations, laboratory examinations, imaging studies, and treatment strategies were obtained for all patients. RESULTS: Most patients presented with hypopituitarism and headaches, while some presented with fever, visual disturbances, and diabetes insipidus (DI). Abscesses showed significant annular enhancement post gadolinium injection. In most patients, pituitary abscess can be cured via microscopic or endoscopic drainage of the abscess followed by antibiotic treatment. Complete cure of pituitary abscess was observed in nine patients, with six cases of prolonged hypopituitarism and only one case of recurrence. Long-term hormone replacement therapy was effective in the postoperative management of hypopituitarism. CONCLUSIONS: The typical manifestations of pituitary abscess include hypopituitarism and headaches; the presence of an enhanced ring at the edge of the mass on contrast-enhanced magnetic resonance images (MRI) is highly suggestive of pituitary abscess. We recommend antibiotic treatment for 4-6 weeks postoperatively, based on the results of bacterial cultures or metagenomic next-generation sequencing (mNGS).

5.
J Cancer Res Clin Oncol ; 149(17): 16055-16067, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37695389

RESUMO

PURPOSE: Glioblastoma is one of the malignant tumors with poor prognosis and no effective treatment is available at present. METHODS: To study the effect of cordycepin combined with temozolomide on glioblastoma, we explored the effect of the combination based on network pharmacology and biological verification. RESULTS: It was found that the drug combination significantly inhibited the cell growth, proliferation, migration and invasion of LN-229 cells. Drug combination inhibited epithelial-mesenchymal transition (EMT) by up-regulating the expression of E-cadherin and suppressing the expression of N-cadherin, Zeb1 and Twist1. Through network pharmacology, we further explored the molecular mechanism of drug combination against glioblastoma, and 36 drug-disease common targets were screened. The GO biological process analysis included 44 items (P < 0.01), which mainly involved the regulation of apoptosis, cell proliferation, cell migration, etc. The enrichment analysis of KEGG pathways included 28 pathways (P < 0.05), and the first four pathways were "MicroRNA in cancer, Proteoglycans in cancer, Pathways in cancer and PI3K-AKT signaling pathway". We detected the expression of important genes in the pathways and PPI network, and the results showed that the drug combination down-regulated NFKB1, MYC, MMP-9, MCL1, CTNNB1, and up-regulated PDCD4. CONCLUSION: Cordycepin combined with temozolomide may down-regulate MYC through "MicroRNA in cancer, Proteoglycans in cancer, Pathways in cancer and PI3K-AKT signaling pathway", which in turn regulate the expression of MCL1, CTNNB1, MMP9, PDCD4, thus regulating cell proliferation, migration and apoptosis in glioblastoma.


Assuntos
Glioblastoma , MicroRNAs , Humanos , Temozolomida/farmacologia , Temozolomida/uso terapêutico , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Glioblastoma/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Proteína de Sequência 1 de Leucemia de Células Mieloides/uso terapêutico , Linhagem Celular Tumoral , MicroRNAs/genética , Proliferação de Células , Combinação de Medicamentos , Proteoglicanas/metabolismo , Proteoglicanas/farmacologia , Proteoglicanas/uso terapêutico , Proteínas de Ligação a RNA , Proteínas Reguladoras de Apoptose/metabolismo
6.
BMJ Support Palliat Care ; 13(4): 445-452, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32917650

RESUMO

OBJECTIVES: To investigate the body composition and dietary intake in the patients with head and neck cancer (HNC) during radiotherapy (RT), and explore the relationship between them. METHODS: This was a prospective, longitudinal observational study. Adult patients with HNC undergoing RT between March 2017 and August 2018 were recruited. Patients' body compositions were evaluated by bioelectrical impedance analysis, and dietary intake was recorded by 24-hour dietary recall at three time points, including baseline (T1), mid-treatment (T2) and post-treatment (T3). Patients were divided into low, middle and high energy intake groups based on the average daily energy intake (DEI). Changes in body weight (BW), fat mass (FM), fat-free mass (FFM) and skeletal muscle mass (SMM) among these three groups were compared. RESULTS: From T1 to T3, the median loss of patients' BW, FM, FFM and SMM was 4.60, 1.90, 2.60 and 1.50 kg, respectively. The loss of BW was more dramatic from T2 to T3 than that from T1 to T2. BW loss was mainly contributed by SMM loss from T1 to T2 and by FM loss from T2 to T3. Meanwhile, patients' dietary intake reduced during treatment. High DEI group had a significantly attenuated loss of patients' BW, FFM, SMM and FM compared with the low DEI group. CONCLUSION: Patients' BW, FM, FFM and SMM all significantly reduced, especially from T2 to T3, with decreased DEI during RT, which stresses the importance of nutrition intervention during the whole course of RT.


Assuntos
Composição Corporal , Neoplasias de Cabeça e Pescoço , Adulto , Humanos , Estudos Longitudinais , Estudos Prospectivos , Composição Corporal/fisiologia , Peso Corporal , Ingestão de Alimentos , Neoplasias de Cabeça e Pescoço/radioterapia
7.
PeerJ ; 10: e12942, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35186504

RESUMO

BACKGROUND: Glioblastoma is the most common and fatal primary malignant tumor in the central nervous system, and the prognosis is poor. Currently, there are no effective treatments for glioblastoma. Cordycepin is a natural active substance with significant anticancer activity and doxorubicin is a broad-spectrum anticancer drug. Cordycepin administered with doxorubicin is a potential drug combination for the treatment of glioblastoma. However, the mechanism of action for this drug combination has not yet been elucidated. AIM OF THE STUDY: To explore the complex mechanism of cordycepin combined with doxorubicin against glioblastoma using network pharmacology and biological verification. MATERIALS AND METHODS: We used an MTT assay, colony formation assay, and scratch healing to detect the growth, proliferation, and migration of LN-229, U251 and T98G cells. Putative targets and the potential mechanism of action for the drug combination in glioblastoma were obtained through online databases, network construction, and enrichment analyses. We verified the expression of EMT-related genes and identified important therapeutic targets by western blot. RESULTS: In this study, the combination of doxorubicin and cordycepin was found to significantly inhibit cell proliferation and migration and can induce apoptosis. These effects are better together than with either drug alone. The drug combination inhibited EMT by upregulating the expression of E-cadherin protein and downregulating the expression of N-cadherin, ZEB1, and Twist1 proteins. There were 71 potential targets for the drug combination in glioblastoma, and Kyoto Encyclopedia of Genes and Genome analysis suggested that the anticancer process may be mediated by proteoglycans in cancer, the tumor necrosis factor signaling pathway, microRNA in cancer, pathways in cancer, and other pathways. To study the molecular mechanism of anticancer activity, we detected the expression of target proteins with downregulated expression of NFKB1, MAPK8, MYC, and MMP-9 proteins and upregulated expression of cleaved caspase 3 that promoted the apoptosis of LN-229 cells. CONCLUSIONS: This study shows that the drug combination of doxorubicin and cordycepin effectively inhibits the growth and proliferation of LN-229 cells through multiple targets and multiple pathways, and the combination inhibits cell invasion and migration by regulating the EMT switch of tumor cells. Our findings provide new ideas about, and a theoretical basis for, the treatment of glioblastoma.


Assuntos
Glioblastoma , Humanos , Glioblastoma/tratamento farmacológico , Farmacologia em Rede , Linhagem Celular Tumoral , Doxorrubicina/farmacologia , Fatores de Transcrição/uso terapêutico
8.
Head Neck ; 44(9): 2046-2054, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35915864

RESUMO

BACKGROUND: Body composition may influence the prognosis of head and neck cancer (HNC) patients. To find out the most crucial factors in this relationship, we explored the association between body composition and survival. METHODS: In this prospective longitudinal study, HNC patients who underwent radiotherapy (RT) from March 2017 to December 2018 were recruited. The association between body composition and survival was analyzed using Cox proportional hazard regression. RESULTS: Final analysis included 316 patients, with a median follow-up of 34.4 months. Multivariable analysis revealed that weight loss 6 months before RT and body composition changes during RT did not affect the survival outcome. However, patients with low appendicular skeletal muscle mass index (ASMI) before RT exhibited poor overall survival (OS). ASMI before RT was an independent prognostic factor for OS. CONCLUSIONS: Body composition loss was common during RT, and ASMI before RT independently influenced the survival outcomes of HNC patients.


Assuntos
Neoplasias de Cabeça e Pescoço , Composição Corporal , Neoplasias de Cabeça e Pescoço/radioterapia , Humanos , Estudos Longitudinais , Prognóstico , Estudos Prospectivos
9.
Int J Med Inform ; 161: 104733, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35299099

RESUMO

PURPOSE: To develop and validate machine learning (ML) models for cancer-associated deep vein thrombosis (DVT) and to compare the performance of these models with the Khorana score (KS). METHODS: We randomly extracted data of 2100 patients with cancer between Jan. 1, 2017, and Oct. 31, 2019, and 1035 patients who underwent Doppler ultrasonography were enrolled. Univariate analysis and Lasso regression were applied to select important predictors. Model training and hyperparameter tuning were implemented on 70% of the data using a ten-fold cross-validation method. The remaining 30% of the data were used to compare the performance with seven indicators (area under the receiver operating characteristic curve [AUC], sensitivity, specificity, accuracy, balanced accuracy, Brier score, and calibration curve), among all five ML models (linear discriminant analysis [LDA], logistic regression [LR], classification tree [CT], random forest [RF], and support vector machine [SVM]), and the KS. RESULTS: The incidence of cancer-associated DVT was 22.3%. The top five predictors were D-dimer level, age, Charlson Comorbidity Index (CCI), length of stay (LOS), and previous VTE (venous thromboembolism) history according to RF. Only LDA (AUC = 0.773) and LR (AUC = 0.772) outperformed KS (AUC = 0.642), and combination with D-dimer showed improved performance in all models. A nomogram and web calculator https://webcalculatorofcancerassociateddvt.shinyapps.io/dynnomapp/ were used to visualize the best recommended LR model. CONCLUSION: This study developed and validated cancer-associated DVT predictive models using five ML algorithms and visualized the best recommended model using a nomogram and web calculator. The nomogram and web calculator developed in this study may assist doctors and nurses in evaluating individualized cancer-associated DVT risk and making decisions. However, other prospective cohort studies should be conducted to externally validate the recommended model.


Assuntos
Neoplasias , Trombose Venosa , Humanos , Modelos Logísticos , Aprendizado de Máquina , Neoplasias/complicações , Neoplasias/epidemiologia , Estudos Prospectivos , Trombose Venosa/diagnóstico , Trombose Venosa/epidemiologia , Trombose Venosa/etiologia
10.
Eur J Oncol Nurs ; 53: 101943, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34281789

RESUMO

PURPOSE: Our study aims to investigate dietary intake characteristics and their association with skeletal muscle mass in head and neck cancer patients treated with radiotherapy. METHODS: From March 2017 to August 2018, patients with head and neck cancer who received radiotherapy at our affiliated hospital were enrolled. Dietary intake was assessed through 24-hr dietary recall and skeletal muscle mass was evaluated by bioelectrical impedance analysis at three-time points. Appendicular skeletal muscle mass was adjusted for height squared defined sarcopenia and correlated with dietary intake by generalized estimating equations (GEE). RESULTS: This study sample comprised 287 patients [median age: 54 years; 187 (65.2%) men]. Median dietary intake at post-treatment was 14.95 kcal/kg/day energy and 0.63 g/kg/day protein. Skeletal muscle mass decreased significantly in all patients. The prevalence of sarcopenia increased from 24.4% before treatment to 46.7% at the end of treatment. Exploratory univariate GEE analysis revealed that radiotherapy time-point, male-gender, age ≥60 and decreased dietary energy intake significantly impacted on muscle loss represented by the appendicular skeletal muscle index. After controlling covariates, dietary energy intake was only positively associated with muscle loss in women (P = 0.013, 95% CI = 0.003-0.027) but not in men (P = 0.788, 95% CI = -0.007-0.009). CONCLUSION: While the loss in skeletal muscle is more prevalent in men receiving radiotherapy, the effects of dietary energy intake were only associated with women. A prospective randomized clinical trial is required to identify the appropriate amount of dietary energy supplement by gender in cancer patients treated with radiotherapy.


Assuntos
Neoplasias de Cabeça e Pescoço , Sarcopenia , Ingestão de Alimentos , Feminino , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/radioterapia , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/patologia , Prevalência , Estudos Prospectivos , Sarcopenia/epidemiologia , Sarcopenia/etiologia , Sarcopenia/patologia
11.
J Pain Symptom Manage ; 62(2): 277-285, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33348033

RESUMO

OBJECTIVES: The objective of this study was to identify the nutrition impact symptom (NIS) clusters in patients with head and neck cancer (HNC) receiving concurrent chemoradiotherapy (CCRT) and explore their relationships with the weight loss rate (WLR). METHODS: This longitudinal study included 169 patients. At baseline (T1), the demographics, clinical information, and weight before radiotherapy (RT) were recorded. At the third week (T2) and the end of RT (T3), we assessed the weight, prevalence, severity, and interference of the NIS with the Head and Neck Patient Symptom Checklist. The mean scores of the severity of NIS at T2 and T3 were used as a whole to perform the exploratory factor analysis and identify the symptom clusters. Cronbach's α coefficient was used to evaluate the internal consistency of the symptom clusters. Generalized estimating equations were used to analyze the relationships between clusters and the WLR. RESULTS: We extracted three clusters from 14 NISs: the RT-specific symptom cluster including pain, difficulty swallowing, oral mucositis, thick saliva, difficulty chewing, and dry mouth (Cronbach's α = 0.820); the gastrointestinal symptom cluster including nausea, loss of appetite, feeling full, vomiting, and taste change (Cronbach's α = 0.592); the psychological status cluster including depressed, anxious, and lack of energy (Cronbach's α = 0.710). The multivariable model showed that participants with more serious RT-specific symptom cluster (ß = 1.020, 95% CI: 0.570-1.471, P < 0.001) had higher WLR. CONCLUSIONS: The NIS had close internal connections with each other, so the strategies applied by healthcare professionals should focus on multiple related symptoms, especially to manage the RT-specific symptom cluster.


Assuntos
Neoplasias de Cabeça e Pescoço , Quimiorradioterapia/efeitos adversos , Neoplasias de Cabeça e Pescoço/terapia , Humanos , Estudos Longitudinais , Estado Nutricional , Síndrome
12.
World J Gastroenterol ; 21(5): 1636-40, 2015 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-25663784

RESUMO

AIM: To evaluate whether the application of sorafenib during the peri-operative period of liver transplantation improves prognosis in liver cancer patients. METHODS: We searched PubMed, EMBASE and MEDLINE for eligible articles. A total of 4 studies were found that fulfilled the previously agreed-upon standards. We then performed a systematic review and meta-analysis on the enrolled trials that met the inclusion criteria. RESULTS: Out of the 104 studies identified in the database, 82 were not clinical experiments, and 18 did not fit the inclusion standards. Among the remaining 4 articles, only 1 was related to the preoperative use of sorafenib, whereas the other 3 were related to its postoperative use. As the heterogeneity among the 4 studies was high, with an I(2) of 86%, a randomized effect model was applied to pool the data. The application of sorafenib before liver transplantation had a hazard ratio (HR) of 3.29 with a 95% confidence interval (CI) of 0.33-32.56. The use of sorafenib after liver transplantation had an HR of 1.44 (95%CI: 0.27-7.71). The overall pooled HR was 1.68 (95%CI: 0.41-6.91). CONCLUSION: The results showed that the use of sorafenib during the peri-operative period of liver transplantation did not improve patient survival significantly. In fact, sorafenib could even lead to a worse prognosis, as its use may increase the hazard of poor survival.


Assuntos
Antineoplásicos/administração & dosagem , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/cirurgia , Transplante de Fígado , Terapia Neoadjuvante , Niacinamida/análogos & derivados , Compostos de Fenilureia/administração & dosagem , Inibidores de Proteínas Quinases/administração & dosagem , Antineoplásicos/efeitos adversos , Quimioterapia Adjuvante , Distribuição de Qui-Quadrado , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Transplante de Fígado/efeitos adversos , Transplante de Fígado/mortalidade , Terapia Neoadjuvante/efeitos adversos , Terapia Neoadjuvante/mortalidade , Niacinamida/administração & dosagem , Niacinamida/efeitos adversos , Razão de Chances , Compostos de Fenilureia/efeitos adversos , Inibidores de Proteínas Quinases/efeitos adversos , Fatores de Risco , Sorafenibe , Fatores de Tempo , Resultado do Tratamento
13.
Mol Imaging Biol ; 5(6): 418-26, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14667496

RESUMO

Excessive amounts of protein deposits, beta-amyloid (Abeta) plaques, are commonly detected in the postmortem brains of Alzheimer's disease (AD) patients. These Abeta plaques are believed to play an important role in the pathogenesis of the disease. Development of Abeta plaque-specific imaging agents for detecting and monitoring the changes of Abeta plaque deposition in living brains are reported. These agents, if successfully developed, may serve as potential biomarkers for the disease. Several iodinated derivatives based on variety of core structures are labeled with radioiodine as single photon emission computed tomography (SPECT) imaging agents. Thioflavin (or benzothiazole) derivatives displayed excellent in vitro characteristics with high binding affinities for Abeta aggregates (in subnanomolar to nanomolar range) and excellent plaque labeling of AD brain sections. However, the in vivo kinetic properties appeared unfavorable for further development. A novel series of imidazo-pyridine derivative, such as 2-(4'-dimethylaminophenyl)-6-iodo-imidazo[1,2-a]pyridine (IMPY), exhibited highly desirable in vivo properties. Additional structural modification resulting in stilbene derivatives displayed good binding affinities for Abeta aggregates. In addition, fluorene compounds with a rigid tricyclic structure showed in vitro and in vivo characteristics as potential SPECT imaging agents. Criteria for selection of radioiodinated tracers with suitable in vivo properties to detect amyloid plaques are discussed.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Radioisótopos do Iodo , Placa Amiloide/diagnóstico por imagem , Compostos Radiofarmacêuticos , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Animais , Autorradiografia , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Humanos , Técnicas In Vitro , Radioisótopos do Iodo/química , Radioisótopos do Iodo/farmacocinética , Masculino , Camundongos , Camundongos Endogâmicos ICR , Placa Amiloide/metabolismo , Compostos Radiofarmacêuticos/química , Compostos Radiofarmacêuticos/farmacocinética , Tomografia Computadorizada de Emissão de Fóton Único/métodos
14.
Nan Fang Yi Ke Da Xue Xue Bao ; 27(6): 866-9, 2007 Jun.
Artigo em Zh | MEDLINE | ID: mdl-17584657

RESUMO

OBJECTIVE: To observe the histopathological changes of a novel small-caliber vascular graft after implantation in canine theca interna under scanning electron microscope. METHOD: A 3 cm segment of the vascular graft (diameter of 4 mm) was implanted in an end-to-end fashion to bridge the severed carotid artery in 19 healthy dogs. Color Doppler sonography was performed 2 weeks after the operation to observe the patency rate of artificial blood vessel. At 1, 8, 12 and 24 week postimplantation, the arteries (4, 4, 6 and 5, respectively) were collected for optical and scanning electron microscopies after angiography to observe the patency of the arteries. RESULTS: Of the total of 19 arteries, occlusion occurred in 1 at 12 weeks and 1 at 24 weeks. Optical and electron microscopies showed that 1 week after implantation, slight fibroplasias and formation of red thrombus could be seen at the vascular anastomosis without endothelial cell lining. At 8 weeks, the host tissue grew into the lumen of the graft through the pores to form uniform neointima consisting of plenty of collagen fibers, but still without endothelial cells. At 12 weeks, discontinuous endothelial cells were seen to grow on the surface of the neointima. In the middle segment of the vascular graft, immature endothelial cells were found to grow in clusters. The structure of the neointima was loose in comparison with that at the anastomosis, with occasional inflammation cells. Twenty-four weeks after grafting, endothelial cells grew over the entire inner wall of the patent graft, and the surface of the neointima at the anastomosis was lined with continuous endothelial cells. CONCLUSION: The vascular graft can be useful for reconstruction of canine carotid artery defect and achieves good endothelialization 24 weeks after implantation.


Assuntos
Implante de Prótese Vascular/métodos , Prótese Vascular , Artérias Carótidas/cirurgia , Modelos Animais , Animais , Artérias Carótidas/diagnóstico por imagem , Artérias Carótidas/fisiologia , Colágeno/metabolismo , Cães , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Células Endoteliais/ultraestrutura , Microscopia Eletrônica de Varredura , Fatores de Tempo , Túnica Íntima/citologia , Túnica Íntima/metabolismo , Túnica Íntima/ultraestrutura , Ultrassonografia Doppler em Cores , Grau de Desobstrução Vascular
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