Derivation and validation of a preoperative prognostic model for resectable pancreatic ductal adenocarcinoma.

BACKGROUND: The prognosis of patients with pancreatic ductal adenocarcinoma (PDAC) remains poor even after radical pancreaticoduodenectomy (PD). The study aimed to develop and validate a novel preoperative prognostic model to accurately predict the long-term survival of patients with PDAC. METHODS: Patients with PDAC of pancreatic head from Chinese PLA General Hospital were included. The preoperative PDAC model with contour plots was developed using a non-linear model in the training cohort and then tested in the validation cohort. RESULTS: Of 421 patients who met the inclusion criteria, 280 were in the training cohort and 141 in the validation cohort. Contour plots for preoperative PDAC model were established to visually predict the survival probabilities of these patients, based on preoperative carbohydrate antigen 19-9, preoperative fibrinogen to albumin ratio and pain symptoms. This model stratified patients into low- and high-risk groups with distinctly different long-term survival in the training cohort [median overall survival (OS) 32.1 vs. 17.5 months; median recurrence-free survival (RFS) 19.3 vs. 10.0 months, both P < 0.001] and the validation cohort (median OS 28.3 vs. 19.0 months; median RFS 17.5 vs. 11.2 months, both P < 0.001). Time-dependent receiver operating characteristic and decision curve analyses revealed that the model provided higher diagnostic accuracy and superior net benefit compared to other staging systems. CONCLUSIONS: This study constructed and validated a novel preoperative prognostic model that can accurately and conveniently predict the long-term survival of patients with resectable PDAC of pancreatic head. Besides, the model can screen high-risk patients with poor prognosis, which may provide references for personal treatment strategies in the future.

Step-by-step and orderly lowering of the height of inferior vena cava tumor thrombus is the key to robot-assisted thrombectomy for Mayo III/IV tumor thrombus.

BACKGROUND: The surgical management of Mayo III/IV tumor thrombi is difficult and risky, and robotic surgery is even more difficult. The purpose of this study was to introduce the step-by-step and orderly lowering of the height of inferior vena cava tumor thrombus, which was the core technique of robot operation for Mayo III/IV tumor thrombus. METHOD: A total of 18 patients were included in this study. The average tumor thrombus height was 2.4 cm above the level of the second porta hepatis (SPH), and 9 patients were prepared for cardiopulmonary bypass (CPB) before surgery. During the operation, the height of the tumor thrombus was lowered orderly for 2-3 times, and the blood flow blocking method was changed sequentially. The CPB was required when tumor thrombus in the atrium; After the height of the thrombus was lowered to the atrium entrance, CPB was stopped and the blood flow was blocked in the upper- and retro-hepatic inferior vena cava (IVC); After the tumor thrombus continued to descend to the lower part of the SPH, liver blood flow could be restored, and then, the blood flow was simply blocked in the retro-hepatic IVC to complete the removal of the thrombus and the repair or resection of the IVC. Finally, the diseased kidney and renal vein were removed. RESULTS: All operations were successfully completed, and 2 cases were transferred to laparotomy. Seven cases received CPB, while the other 11 did not. 15 patients underwent two times of the lowering of the tumor thrombus, 2 patients underwent one time and 1 patient underwent three times. The mean liver/IVC dissociation and vascular suspension time was 22.0 min. All patients had less than Clavien-Dindo grade III complications, no serious complications occurred during operation, and no patient died within 90 days. CONCLUSIONS: The step-by-step and orderly decline of tumor thrombus height is the key to the success of robot Mayo III / IV tumor thrombus surgery. This method can shorten FPH and CPB time and improve the success rate of surgery.

A novel online calculator to predict recurrence risk in patients with distal cholangiocarcinoma after radical pancreaticoduodenectomy.

BACKGROUND: Patients with distal cholangiocarcinoma (DCC) are prone to relapse even after radical pancreaticoduodenectomy. In this study, we sought to create an online nomogram calculator to accurately predict the recurrence risk of DCC. METHODS: A total of 184 patients were included. Multivariate Cox regression analysis was used to identify independent prognosis factors for recurrence-free survival and overall survival. A nomogram was constructed according to the prognostic factors in the training cohort and then tested in the validation cohort. RESULTS: Multivariate Cox analysis showed preoperative carbohydrate antigen 19-9 (p < 0.001), maximum tumor size (p = 0.076), perineural invasion (p = 0.044), and N stage (p = 0.076) were independent prognostic factors for DCC relapse. We then constructed a nomogram with these four factors. The consistency index (C-index) of the nomogram in the training and validation cohorts were 0.703 and 0.665, respectively. Time-dependent receiver operating characteristic and decision curve analyses revealed that the nomogram provided higher diagnostic power and net benefit compared with other staging systems. CONCLUSION: In this study, we developed an online nomogram calculator that can accurately predict the recurrence risk of DCC and identify patients with a high risk of recurrence in a simple and convenient manner.

Robotic versus open pancreaticoduodenectomy for distal cholangiocarcinoma: a multicenter propensity score-matched study.

BACKGROUND: Pancreatoduodenectomy is the only potentially curative treatment for distal cholangiocarcinoma (DCC). In this study, we sought to compare the perioperative and oncological outcomes of robotic pancreaticoduodenectomy (RPD) and open pancreaticoduodenectomy (OPD) based on a multicenter propensity score-matched study. METHODS: Consecutive patients with DCC who underwent RPD or OPD from five centers in China between January 2014 and June 2019 were included. A 1:1 propensity score matching (PSM) was performed. Univariable and multivariable Cox regression analyses were used to identify independent prognosis factors for overall survival (OS) and recurrence-free survival (RFS) of these patients. RESULTS: A total of 217 patients and 228 patients underwent RPD and OPD, respectively. After PSM, 180 patients in each group were enrolled. There were no significant differences in operative time, lymph node harvest, intraoperative transfusion, vascular resection, R0 resection, postoperative major morbidity, reoperation, 90-day mortality, and long-term survival between the two groups before and after PSM. Whereas, compared with the OPD group, the RPD group had significantly lower estimated blood loss (150.0 ml vs. 250.0 ml; P < 0.001), and a shorter postoperative length of stay (LOS) (12.0 days vs. 15.0 days; P < 0.001). Multivariable analysis showed carbohydrate antigen 19-9 (CA19-9), R0 resection, N stage, perineural invasion, and tumor differentiation significantly associated with OS and RFS of these patients. CONCLUSIONS: RPD was comparable to OPD in feasibility and safety. For patients with DCC, RPD resulted in similar oncologic and survival outcomes as OPD.

Rapid Analysis of the Quality of Amoxicillin and Clavulanate Potassium Tablets Using Diffuse Reflectance Near-Infrared Spectroscopy.

The cycle-closed dimer of amoxicillin influences its critical quality and is an important impurity in amoxicillin and clavulanate potassium tablets. The quality of the tablets could be rapidly evaluated using the impurity as an indicator. Here, we report a quantitative model to determine the cycle-closed dimer in samples from different manufacturers using diffuse reflectance near-infrared (NIR) spectroscopy by partial least squares regression for one y variable (PLS1) and hierarchical cluster analysis. Because the contents of the (active pharmaceutical ingredients) APIs (amoxicillin and clavulanate potassium) and water are also the important indexes of the tablet quality, three other quantitative models were used to confirm the API data and water content. All of the four models facilitate rapid and complete control of the tablet quality. In addition, quantitative models were validated in terms of specificity, linearity, accuracy, repeatability, and intermediate precision according to the International Conference on Harmonisation guidelines by evaluating the characteristics of the NIR spectra. These results confirmed that the models were satisfactory.

[Update of near-infrared models for testing ceftazidime, water and arginine in ceftazidime for injection].

UNLABELLED: To find a more reasonable index to decide whether the universal quantitative NIR model needs to be updated and to develop a general method to update universal quantitative NIR models, the quantitative models for testing ceftazidime, water and arginine contents in ceftazidime for injection were taken as example. The study was performed by analyzing the similarity between new sample spectra and the training set spectra of the original models. At first, new samples of ceftazidime for injection were divided into five groups by cluster analysis. Then representative samples of each group were selected by sample selection strategy. Spectra of those samples were used to update the original quantitative models. The prediction deviation of the new ceftazidime powder injection samples by the models before and after updating was calculated. Decreasing the prediction deviation was regarded as the standard to decide if the updating was effective. At the same time, the correlation coefficient of new sample spectra and reference sample spectra was defined as the index to study the general method for model updating. (Reference sample refers to training set sample) Finally, the proposed method was validated by updating universal models for testing ceftazidime, water and arginine contents in ceftazidime powder injections. Results show that the correlation coefficient of new sample spectra and training set sample spectra of the original model was calculated within modeling wavelength range. It was proved that when correlation coefficient rT < 96.5%, the model needs to be updated. Accordingly, rT = 96.5% was set as the threshold. The quantitative models were updated by the method mentioned above. As a result, when testing ceftazidime for injection containing sodium carbonate using newly updated models, the average predicting deviation of ceftazidime contents decreased from 8.1% to 2.3%. And the average predicting deviation of water contents decreased from 2.2% to 0.3%. Meanwhile, with regard to samples containing arginine using the updated models, the average predicting deviation of ceftazidime contents decreased from 7.0% to 1.9%. The average predicting deviation of water contents decreased from 0.6% to 0.3%. And that of arginine contents de- creased from 2.3% to 0.4%. CONCLUSION: The newly updated models can be used for testing ceftazidime, water and arginine contens in ceftazidime for injection samples of domestic market. It is reasonable to set rT as the index to decide whether the model needs updating. Moreover, it is necessary to take PCA scores graph of new sample spectra and training set spectra of the original model into account. The proposed method for updating models can be used as a usual approach. And rT = 96.5% can be set as the threshold to determine whether the model needs to be updated.

Ultrasound-guided percutaneous high-frequency irreversible electroporation in porcine livers using four electrode needles: A feasibility and safety study.

BACKGROUND: Malignant liver tumors seriously endanger human health. Among different therapeutic approaches, high-frequency irreversible electroporation (H-FIRE) is a recently emerging tumor ablation technique. The objective of this study was to evaluate the feasibility and safety of ultrasound-guided percutaneous H-FIRE using four electrode needles in porcine livers. METHODS: Twelve experimental pigs underwent percutaneous H-FIRE ablation using a compound steep-pulse therapeutic device. Liver tissues adjacent to the gallbladder, blood vessels, and bile ducts were selected as the ablation targets. Pigs were randomly divided into three groups: (1) immediately after ablation (N = 4), (2) 2 days after ablation (N = 4), and (3) 7 days after ablation (N = 4). Blood routine, liver and kidney function, and myocardial enzyme levels were measured before and after ablation. Ultrasound, contrast-enhanced ultrasound (CEUS), contrast-enhanced magnetic resonance imaging (MRI), and hematoxylin-eosin staining were performed to evaluate the ablation performance. RESULTS: Ultrasound-guided percutaneous H-FIRE ablations using four electrode needles were successfully performed in all 12 experimental pigs. The general conditions of the pigs, including postoperative activities and feeding behaviors, were normal, with no significant changes compared with the preoperative conditions. The imaging features of ultrasound, CEUS, and MRI demonstrated no significant changes in the gallbladder walls, bile ducts, or blood vessels close to the ablation areas. Laboratory tests showed that liver function indices and myocardial enzymes increased temporarily after H-FIRE ablation, but decreased to normal levels at 7 days after ablation. Histopathological examinations of porcine liver specimens showed that this technique could effectively ablate the target areas without damaging the surrounding or internal vascular systems and gallbladder. CONCLUSIONS: This study demonstrated the feasibility and safety of ultrasound-guided percutaneous H-FIRE ablation in porcine livers in vivo, and proposed a four-needle method to optimize its clinical application.

Advances in rapid drug detection technology.

Spurious/Falsely-labeled/Falsified/Counterfeit (SFFC)drugs have become a major threat to public health, especially in rural areas of developing countries.The goal of this review is to provide an overview of rapid detection technologies for counterfeits recently reported, such as Near Infrared Spectroscopy, Near Infrared Chemical Imaging, Raman Spectroscopy, X-Ray Fluorescence, X-RayPowder Diffraction, Ion Mobility Spectrometry, Ion MobilityMass Spectrometry,Isotope Ratio Mass Spectrometry and visual analytical methods The advantages of each of these detection methods are introduced. Examples of characterization of SFFC drugs using the detection technology mentioned are presented. In addition, new characteristics and trends of SFFC drugs are listed and the solution is discussed.

Characterization of Solid-State Drug Polymorphs and Real-Time Evaluation of Crystallization Process Consistency by Near-Infrared Spectroscopy.

Herein, we aimed to develop a strategy for evaluating the consistency of pharmaceutically important crystallization processes in real time, focusing on two typical cases of polymorphism. Theoretical analysis using a combination of 13C solid-state nuclear magnetic resonance spectroscopy with other polymorphism analysis techniques identified a number of marker signals, the changes of which revealed the presence of two or more structural orientations (lattices and/or molecular conformations) in both cefazolin sodium pentahydrate (α-CEZ-Na) and cephathiamidine (CETD). The proportions of these forms were shown to be batch-dependent and were defined as critical quality attributes (CQAs) to evaluate process consistency. Subsequently, real-time analysis by chemometrics-assisted near-infrared spectroscopy (NIR) was used to obtain useful information corresponding to CQAs. The pretreated spectra of representative samples were transformed by first derivative and vector normalization methods and used to calculate standard deviations at each wavelength and thus detect significant differences. As a result, vibrational responses of H2O, CH3, and CH2 moieties (at 5,280, 4,431, and 4,339 cm-1, respectively) were shown to be sensitive to the CQAs of α-CEZ-Na, which allowed us to establish a highly accurate discrimination model. Moreover, signals of H2O, CONH, and COOH moieties (at 5,211, 5,284, and 5,369 cm-1, respectively) played the same role in the case of CETD, as confirmed by theoretical results. Thus, we established a technique for the rapid evaluation of crystallization process consistency and deepened our understanding of crystallization behavior by using NIR in combination with polymorphism analysis techniques.

Compilation of a Near-Infrared Library for Construction of Quantitative Models of Oral Dosage Forms for Amoxicillin and Potassium Clavulanate.

The accuracy of quantitative models for near-infrared (NIR) spectroscopy is dependent upon calibration samples with concentration variations. Conventional sample-collection methods have shortcomings (especially time-consumption), which creates a "bottleneck" in the application of NIR models for Process Analytical Technology (PAT) control. We undertook a study to solve the problem of sample collection for construction of NIR quantitative models. Amoxicillin and potassium clavulanate oral dosage forms (ODFs) were used as examples. The aim of this study was to find an approach to construct NIR quantitative models rapidly using a NIR spectral library based on the idea of a universal model. The NIR spectral library of amoxicillin and potassium clavulanate ODFs was defined and comprised the spectra of 377 batches of samples produced by 26 domestic pharmaceutical companies, including tablets, dispersible tablets, chewable tablets, oral suspensions, and granules. The correlation coefficient (rT) was used to indicate the similarities of the spectra. The calibration sets of samples were selected from a spectral library according to the median rT of the samples to be analyzed. The rT of the samples selected was close to the median rT. The difference in rT of these samples was 1.0-1.5%. We concluded that sample selection was not a problem when constructing NIR quantitative models using a spectral library compared with conventional methods of determining universal models. Sample spectra with a suitable concentration range in NIR models were collected rapidly. In addition, the models constructed through this method were targeted readily.

Application of Solid-State NMR to Reveal Structural Differences in Cefazolin Sodium Pentahydrate From Different Manufacturing Processes.

Solid-state Nuclear magnetic resonance, thermogravimetric analysis, X-ray diffraction, and Fourier-transform infrared spectroscopy were combined with theoretical calculation to investigate different crystal packings of α-cefazolin sodium obtained from three different vendors and conformational polymorphism was identified to exist in α-cefazolin sodium. Marginal differences observed among cefazolin sodium pentahydrate 1, 2, and 3 were speculated as being caused by the proportion of conformation 2.

Identification of the components of bitespiramycin by liquid chromatography-mass spectrometry.

Reversed-phase liquid chromatography coupled with electrospray ionization tandem mass spectrometry (LC/ESI-MS/MS) was used to characterize the components of bitespiramycin, a group of 4"-acylated spiramycins produced by bioengineered strains. In total 38 components were characterized in commercial samples, including 12 impurities that had never been reported before and 12 other that were partially characterized. The structures of these unknown compounds were deduced by comparison of their fragmentation patterns with those of known major components. Their ultraviolet spectra were used to confirm the presence of an α-, ß-, γ-, δ-unsaturated butadiene in the macrocyclic lactone. Compared with the classical method, LC/ESI-MS/MS is particularly advantageous in terms of sensitivity and efficiency to characterize minor components at trace levels in multi-component antibiotics.