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Minh‐Ha Tran 《ISBT科学丛刊》2019,14(3):289-299
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Andreas Minh Luu Orlin Belyaev Philipp Hhn Michael Praktiknjo Monika Janot Waldemar Uhl Chris Braumann 《Journal of gastrointestinal oncology.》2021,12(2):474
BackgroundPancreatic cancer remains a relevant clinical problem due to poor prognosis. Even after curative pancreaticoduodenectomy tumor recurrences occur in up to 80%. Risk factors for postoperative tumor recurrences have been identified before, but data on risk factors for tumor recurrences in patients with long-term-survival is scarce.MethodsIn this retrospective study consecutive long-term survival-patients (defined as at least 60 months survival) undergoing pancreaticoduodenectomy for pancreatic cancer from 2007–2014 were identified in the 2nd largest pancreatic surgery center in Germany. Clinical, pathohistological and laboratory values were analyzed to identify risk factors for tumor recurrence.ResultsThirty-four of one-hundred-sixty-seven patients were identified as long-term-survival-patients in the study period. Of those, 10 patients (29.4%) suffered from tumor recurrence. Lymph vessel invasion was identified as an independent risk factor (P=0.031, hazard ratio 13.127, 95% confidence interval: 1.270–135.698). Median postoperative time to tumor recurrence in long-term-survival-patients was 49 months. Overall survival after diagnosis of tumor recurrence was 33 months. 80% (N=8) of the patients were asymptomatic. Half of the patients (N=5) suffered from local disease, with 40% undergoing curative tumor resection. CA 19-9 levels were significantly elevated at 57 U/mL (normal <27 U/mL).ConclusionsTumor recurrence in long-term-survival-patients is typically asymptomatic. Especially long-term-survival-patients with lymph vessel invasion are more likely to develop tumor recurrence. Therefore, a structured follow-up program including CT-scans and CA 19-9 surveillance must be continued in all patients undergoing pancreaticoduodenectomy even in cases of long-term-survival. 相似文献
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Trong N. Nguyen Anthony S. Podkowa Trevor H. Park Rita J. Miller Minh N. Do Michael L. Oelze 《Ultrasound in medicine & biology》2021,47(3):556-568
Quantitative ultrasound (QUS) was used to classify rabbits that were induced to have liver disease by placing them on a fatty diet for a defined duration and/or periodically injecting them with CCl4. The ground truth of the liver state was based on lipid liver percents estimated via the Folch assay and hydroxyproline concentration to quantify fibrosis. Rabbits were scanned ultrasonically in vivo using a SonixOne scanner and an L9-4/38 linear array. Liver fat percentage was classified based on the ultrasonic backscattered radiofrequency (RF) signals from the livers using either QUS or a 1-D convolutional neural network (CNN). Use of QUS parameters with linear regression and canonical correlation analysis demonstrated that the QUS parameters could differentiate between livers with lipid levels above or below 5%. However, the QUS parameters were not sensitive to fibrosis. The CNN was implemented by analyzing raw RF ultrasound signals without using separate reference data. The CNN outputs the classification of liver as either above or below a threshold of 5% fat level in the liver. The CNN outperformed the classification utilizing the QUS parameters combined with a support vector machine in differentiating between low and high lipid liver levels (i.e., accuracies of 74% versus 59% on the testing data). Therefore, although the CNN did not provide a physical interpretation of the tissue properties (e.g., attenuation of the medium or scatterer properties) the CNN had much higher accuracy in predicting fatty liver state and did not require an external reference scan. 相似文献
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Genetic and Environmental Variances of Bone Microarchitecture and Bone Remodeling Markers: A Twin Study 下载免费PDF全文
Åshild Bjørnerem Minh Bui Xiaofang Wang Ali Ghasem‐Zadeh John L Hopper Roger Zebaze Ego Seeman 《Journal of bone and mineral research》2015,30(3):519-527
All genetic and environmental factors contributing to differences in bone structure between individuals mediate their effects through the final common cellular pathway of bone modeling and remodeling. We hypothesized that genetic factors account for most of the population variance of cortical and trabecular microstructure, in particular intracortical porosity and medullary size – void volumes (porosity), which establish the internal bone surface areas or interfaces upon which modeling and remodeling deposit or remove bone to configure bone microarchitecture. Microarchitecture of the distal tibia and distal radius and remodeling markers were measured for 95 monozygotic (MZ) and 66 dizygotic (DZ) white female twin pairs aged 40 to 61 years. Images obtained using high‐resolution peripheral quantitative computed tomography were analyzed using StrAx1.0, a nonthreshold‐based software that quantifies cortical matrix and porosity. Genetic and environmental components of variance were estimated under the assumptions of the classic twin model. The data were consistent with the proportion of variance accounted for by genetic factors being: 72% to 81% (standard errors ~18%) for the distal tibial total, cortical, and medullary cross‐sectional area (CSA); 67% and 61% for total cortical porosity, before and after adjusting for total CSA, respectively; 51% for trabecular volumetric bone mineral density (vBMD; all p < 0.001). For the corresponding distal radius traits, genetic factors accounted for 47% to 68% of the variance (all p ≤ 0.001). Cross‐twin cross‐trait correlations between tibial cortical porosity and medullary CSA were higher for MZ (rMZ = 0.49) than DZ (rDZ = 0.27) pairs before (p = 0.024), but not after (p = 0.258), adjusting for total CSA. For the remodeling markers, the data were consistent with genetic factors accounting for 55% to 62% of the variance. We infer that middle‐aged women differ in their bone microarchitecture and remodeling markers more because of differences in their genetic factors than differences in their environment. © 2014 American Society for Bone and Mineral Research. 相似文献
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Pharmacokinetics of oral and intravenous ofloxacin in children with multidrug-resistant typhoid fever. 总被引:3,自引:1,他引:3 下载免费PDF全文
D B Bethell N P Day N M Dung C McMullin H T Loan D T Tam L T Minh N T Linh N Q Dung H Vinh A P MacGowan L O White N J White 《Antimicrobial agents and chemotherapy》1996,40(9):2167-2172
The pharmacokinetics of oral and intravenous ofloxacin (7.5 mg.kg of body weight-1 given over 30 min) were studied in an open crossover study of 17 Vietnamese children, aged between 5 and 14 years, with acute uncomplicated typhoid fever. Following oral administration, the median (95% confidence interval [CI]) time to peak concentration of ofloxacin in serum (Cmax) was 1.7 h (1.4 to 1.9 h) and the mean (95% CI) Cmax was 5.5 mg.liter-1 (4.7 to 6.3 mg.liter-1) compared with a Cmax of 8.7 mg.liter-1 (7.6 to 9.7 mg.liter-1) following the intravenous infusion. The median (95% CI) total apparent volume of distribution following the first intravenous dose, 1.35 liter.kg-1 (1.17 to 1.73 liter.kg-1), was significantly larger than that following the second dose, 0.99 liter.kg-1 (0.86 to 1.17 liter.kg-1; P < 0.0005), although the estimates for systemic clearance were similar: 0.255 liter.kg-1 h-1 (0.147 to 0.325 liter.kg-1 h-1) compared with 0.172 liter.kg-1 h-1 (0.127 to 0.292 liter.kg-1 h-1; P = 0.14). The mean residence times (95% CI) following intravenous and oral administration were similar: 5.24 h (4.84 to 6.58 h) and 6.24 h (5.32 to 7.85 h), respectively. The mean (95% CI) oral bioavailability was 91% (74 to 109%). The peak concentrations in serum were 10 to 100 times higher than the maximum MICs for ofloxacin against multidrug-resistant Salmonella typhi isolated in this area. Although the systemic clearance values were higher than those reported previously for adults, these data overall suggest that weight-or area-adjusted dose regimens for the treatment of typhoid in older children should be the same as those for adults. 相似文献
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Thi Minh Chau Ngo Phuong Anh Ton Nu Chi Cao Le Minh Tiep Vo Thi Ngoc Thuy Ha Thi Bich Thao Do Phuoc Vinh Nguyen Giang Tran Thi Antonella Santona 《Journal de Mycologie Médicale》2022,32(3):101291
BackgroundNannizzia incurvata, a species belonging to the Nannizzia gypsea complex, is considered a neglected pathogen.ObjectiveTo detected N. incurvata isolates from dermatophytosis patients in Hue city - Viet Nam, and test the antifungal susceptibility of this species. Moreover, fungal capability to produce hydrolytic enzymes was evaluated.MethodsPatients’ samples were collected and cultured on Sabouraud-chloramphenicol-cycloheximide medium. Dermatophytes isolates were initially macroscopically and microscopically identified. ITS PCR-RFLP and ITS rDNA sequences were performed to determine and confirm species. An ITS Neighbor-Joining phylogenetic tree evaluated the genetic relationship among isolates. Fungal hydrolytic enzymes were examined, including lipase, phospholipase and protease. Antifungal susceptibility testing was carried out by the disk diffusion method. MICs of itraconazole, voriconazole, and terbinafine against these isolates were determined by the broth microdilution method.ResultsTwelve isolates of N. gypsea complex were preliminary morphologically identified. PCR-RFLP and ITS-rDNA sequencing identified and confirmed dermatophytes as N. incurvata strains, respectively. An evident polymorphism among isolates was highlighted in the phylogenetic tree. All isolates showed the activity of lipase, phospholipase, and protease production. Overall, all N. incurvata isolates were susceptible to itraconazole, voriconazole, clotrimazole, miconazole, and terbinafine. Few isolates were susceptible to griseofulvin, and none of them were susceptible to fluconazole.ConclusionsThere was a presence of polyclonal N. incurvata isolates in dermatophytosis patients from Hue city, identified by PCR-RLFP and confirmed by ITS sequencing. We confirmed PCR-RLFP as a reliable technique to identify this species. Azole and terbinafine are the optimal choices for N. incurvata treatment except for fluconazole. 相似文献