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701.
Endogenous fluorescence provides morphological, spectral, and lifetime contrast that can indicate disease states in tissues. Previous studies have demonstrated that two-photon autofluorescence microscopy (2PAM) can be used for noninvasive, three-dimensional imaging of epithelial tissues down to approximately 150 μm beneath the skin surface. We report ex-vivo 2PAM images of epithelial tissue from a human tongue biopsy down to 370 μm below the surface. At greater than 320 μm deep, the fluorescence generated outside the focal volume degrades the image contrast to below one. We demonstrate that these imaging depths can be reached with 160 mW of laser power (2-nJ per pulse) from a conventional 80-MHz repetition rate ultrafast laser oscillator. To better understand the maximum imaging depths that we can achieve in epithelial tissues, we studied image contrast as a function of depth in tissue phantoms with a range of relevant optical properties. The phantom data agree well with the estimated contrast decays from time-resolved Monte Carlo simulations and show maximum imaging depths similar to that found in human biopsy results. This work demonstrates that the low staining inhomogeneity (~ 20) and large scattering coefficient (~ 10 mm(-1)) associated with conventional 2PAM limit the maximum imaging depth to 3 to 5 mean free scattering lengths deep in epithelial tissue. 相似文献
702.
Casas-Melley AT Malatack J Consolini D Mann K Raab C Flynn L Woolfrey P Menendez J Dunn SP 《Journal of pediatric surgery》2007,42(1):184-187
Background
Treatment of children with stage III and IV hepatoblastoma has shown little improvement with 5-year survival rates of 64% and 25%, respectively (J Clin Oncol 2000;18:2665-75). A timely and organized treatment program including preoperative chemotherapy combined with living donor liver transplantation and postoperative chemotherapy has been used seeking improved long-term survival in stage III and IV cases.Methods
A retrospective review of 8 patients with stage III and IV hepatoblastoma unresectable by conventional resection were treated with complete hepatectomy and transplantation. Approval was obtained from our institutional review board.Results
Since August of 2001, we have treated 6 patients with stage III hepatoblastoma and 2 patients with initial stage IV hepatoblastoma. These patients (age, 23 months-9 years) had all received extensive chemotherapy or prior resections. After chemotherapy, none had gross tumor documented outside of the liver at time of transplantation. All underwent hepatectomy including vena cava resection, in selected cases, with living donor orthotopic liver transplantation. All patients had at least 2 cycles of postoperative chemotherapy. Of 8 patients, 6 are alive and well with normalized alpha-fetoprotein levels. There were 2 late deaths from recurrent disease. Length of follow-up ranged from 7 to 53 months.Conclusion
Complete hepatectomy with living donor liver transplantation provides optimal surgical treatment in unresectable stage III and initial stage IV disease confined to the liver at resection. This series indicates that children tolerate complete hepatectomy, transplantation, and postoperative chemotherapy well. Referral to a transplant center during the first 3 cycles of chemotherapy appears to offers the best opportunity for long-term survival. 相似文献703.
Oudard S Banu E Vieillefond A Fournier L Priou F Medioni J Banu A Duclos B Rolland F Escudier B Arakelyan N Culine S;GETUG 《The Journal of urology》2007,177(5):1698-1702
PURPOSE: Collecting duct carcinoma of the kidney is a rare and aggressive neoplasm of the distal collecting tubules for which there is no established treatment. Since the histology of collecting duct carcinoma is similar to that of urothelial carcinoma, the standard chemotherapy regimen defined by a gemcitabine and platinum salts combination was prospectively investigated in patients with metastatic collecting duct carcinoma. MATERIALS AND METHODS: A total of 23 patients with metastatic collecting duct carcinoma with no prior systemic chemotherapy were treated with 1,250 mg/m(2) gemcitabine on days 1 and 8 plus 70 mg/m(2) cisplatin or carboplatin (AUC 5) in patients with renal insufficiency on day 1. The drugs were repeated every 21 days for 6 cycles according to toxicity and efficacy. The objective response rate was the primary end point. RESULTS: There were 1 complete and 5 partial responses for an objective response rate of 26% (95% CI 8 to 44). Median progression-free and overall survival was 7.1 (95% CI 3 to 11.3) and 10.5 months (95% CI 3.8 to 17.1), respectively. Toxicity was mainly hematological with grade 3-4 neutropenia and thrombocytopenia in 52% and 43% of patients, respectively. The severity of granulocytopenia and the number of metastatic sites were associated with overall survival on univariate and multivariate analyses. CONCLUSIONS: To our knowledge this is the first prospective, multicenter, phase II study showing that the platinum salts combination is an active and safe regimen as first line treatment in patients with metastatic collecting duct carcinoma. This platinum based chemotherapy should be considered the standard regimen in these patients. 相似文献
704.
Vlcek M Radikova Z Penesova A Kvetnansky R Imrich R 《Autonomic neuroscience : basic & clinical》2008,143(1-2):53-57
The low frequency component of heart rate variability (HRV) is believed to be affected by sympathetic activity, but an evidence for this suggestion remains controversial. This study analyzed association between HRV and plasma catecholamines in response to two distinct conditions activating sympathetic nervous system. Changes in HRV were analysed from ECG recording and plasma norepinephrine and epinephrine levels were measured in response to head-up tilt (60 degrees, 10 min) in 14 healthy volunteers (6 males, mean age 27.2+/-0.8) and in response to insulin-induced hypoglycemia (0.1 IU per kg, i.v. bolus) in 11 healthy volunteers (5 males, mean age 26.6+/-0.9 yr). Normalized low frequency power, low/high frequency ratio, plasma catecholamines increased, whereas normalized high frequency power decreased in response to head-up tilt or hypoglycemia. When analyzed individual time points of orthostatic test, plasma epinephrine correlated positively with low/high frequency ratio and negatively with normalized high frequency at the 3rd min of the head-up tilt. When all data at different time points were pooled significant correlations were found between catecholamines and normalized low frequency power and low/high frequency ratio. In insulin-induced hypoglycemia test plasma epinephrine correlated negatively with normalized high frequency power at the 30th minute. When all data measured at different time points were pooled no significant correlation was found between plasma catecholamines and HRV parameters. In conclusion, the present study shows an increase in low frequency component of HRV in response to orthostasis or hypoglycemia with significant, however inconsistent association to changes in plasma catecholamines. 相似文献
705.
Genetic immunization with LYVE-1 cDNA yields function-blocking antibodies against native protein 总被引:2,自引:0,他引:2
Cardones AR Leitner WW Fang L Murakami T Kapoor V Udey MC Hwang ST 《Microvascular research》2006,71(1):32-39
LYVE-1 is a surface bound hyaluronic acid (HA) receptor that is preferentially expressed by lymphatic endothelial cells (LEC). cDNA encoding full-length human LYVE-1 was coated onto gold particles that were then delivered via helium-assisted jet propulsion (gene gun) into the skin of Balb/C mice. LYVE-1 antisera, but not control pre-immune sera, recognized LYVE-1-transfected 293T cells by flow cytometry. While 40-70% of cultured human dermal microvascular endothelial cells (HMEC) were positive for LYVE-1 staining, human lung microvascular endothelial cells (LMEC) were negative. LYVE-1 antisera was used to effectively separate HMEC into LYVE-1 (hi) and LYVE-1(lo) populations that were enriched or depleted, respectively, for podoplanin, another LEC marker. By immunohistochemistry, LYVE-1 antisera detected CD31(lo) podoplanin(hi) lymphatic channels in normal and psoriatic human skin as well as in human tonsil. LYVE-1 antisera also blocked binding of FITC-labeled HA to HMEC (but not LMEC), demonstrating that these antibodies recognized regions of LYVE-1 required for HA binding. In summary, gene gun-assisted delivery of cDNA encoding LYVE-1 into skin resulted in reliable production of antisera that specifically and functionally recognized native LYVE-1 protein. 相似文献
706.
Multidetector CT (MDCT) is increasingly used for imaging congenital heart disease (CHD) patients in addition to echocardiography,
due to its ability to provide high quality three-dimensional images, giving a comprehensive evaluation of complex heart malformations.
Using 4-slice or 16-slice CT, diagnostic information in CHD patients is limited to extra-cardiac anatomy, mainly the pulmonary
arteries, aorta and venous connections. Due to high heart rates in babies however, coronary evaluation and intra-cardiac analysis
were not reliable with the first generations of MDCT. Larger detector size with 64-slice CT and faster acquisition time, up
to 75 ms for one slice, has progressively improved coronary and intra-cardiac visualization. Because radiation dose is the
main concern, especially in children, every attempt to minimize dose whilst preserving image quality is important: the ALARA
concept should always be applied in this population. The 80 kVp setting is now well accepted as a standard for more and more
radiological teams involved in CT of children. Different acquisition strategies are now possible for childhood coronary imaging,
using retrospective or even prospective gating. Using the latest technology, sub-mSv acquisitions are now attainable for scanning
a whole thorax, providing a complete analysis of any 3-D cardiac malformation, including coronary artery course visualisation.
This review will describe how technological developments have improved image quality with continuous reduction of radiation
dose. 相似文献
707.
Julia Bohosova Marek Kasik Adela Kubickova Karolina Trachtova Michal Stanik Alexandr Poprach Ondrej Slaby 《Journal of clinical laboratory analysis》2022,36(6)
BackgroundRenal cell carcinoma is difficult to diagnose and unpredictable in disease course and severity. There are no specific biomarkers for diagnosis and prognosis estimation feasible in clinical practice. Long non‐coding RNAs (lncRNAs) have emerged as potent regulators of gene expression in recent years. Aside from their cellular role, their expression patterns could be used as a biomarker of ongoing pathology.MethodsIn this work, we used next‐generation sequencing for global lncRNA expression profiling in tumor and non‐tumor tissue of RCC patients. The four candidate lncRNAs have been further validated on an independent cohort. PVT1, as the most promising lncRNA, has also been studied using functional in vitro tests.ResultsNext‐generation sequencing showed significant dysregulation of 1163 lncRNAs; among them top 20 dysregulated lncRNAs were AC061975.7, , AC124017.1, AC148477.4, LINC02437, GATA3‐AS, LINC01762, LINC01230, LINC01271, LINC01187, LINC00472, AP000696.1, LINC00982, LINC01543, AC007849.1, and AL031710.1 as down‐regulated lncRNAs; and SLC16A1‐AS1, PVT1, LINC0887, and LUCAT1 as up‐regulated lncRNAs. We observed statistically significant dysregulation of PVT1, LUCAT1, and LINC00982. Moreover, we studied the effect of artificial PVT1 decrease in renal cell line 786–0 and observed an effect on cell viability and migration.ConclusionOur results show not only the diagnostic but also the therapeutic potential of PVT1 in renal cell carcinoma. AC019197.1相似文献
708.
Bethany A. Harris Adela Scharff Melanie Smith Gayle Brooks Heather Thompson-Brenner James F. Boswell 《Clinical psychology & psychotherapy》2023,30(2):302-316
Baseline interpersonal problems have been associated with treatment outcome in eating disorders (ED) and are important for understanding ED maintenance and aetiology. Despite this evidence, little is known about trajectories of change in interpersonal problems in the context of treatment, particularly in intensive ED treatment. This study examined the trajectory of total interpersonal problems in residential ED treatment, as well as two subdomains previously highlighted in ED research of being overly Cold (interpersonally distant) or overly Domineering (interpersonally controlling), as a function of different primary presenting ED diagnoses: anorexia nervosa restricting subtype (AN-R), binge-purge subtype (AN-BP), and bulimia nervosa or binge eating (BN/BED). Interpersonal problem data were collected at admission, discharge, and 6-month follow-up. Trajectories were analysed with multilevel models. Results showed small-to-medium statistically significant reductions in interpersonal problems across diagnostic groups from admission to discharge for total interpersonal scores, and gains appeared to be maintained at follow-up for both AN groups. Patients diagnosed with primary AN experienced steeper declines in total interpersonal problems from admission to follow-up compared with patients diagnosed with BN/BED, with AN-R experiencing the steepest trajectory. Planned contrasts indicated anyone with relevant binge eating behaviours had higher average levels of both Cold, as well as Domineering problems. Exploratory contrasts suggested that patients who had more Domineering problems also exhibited more binge symptoms and were typically slower to improve. Overall, results suggest interpersonal problems are generally malleable in residential ED treatment, yet change patterns differ by presenting ED symptoms and interpersonal problem subdomain. 相似文献
709.