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Undifferentiated sarcoma of the liver is rare, especially in adults, and is an aggressive malignancy that originates from the primary mesenchymal tissues. A 53-year-old man was referred to our hospital for further evaluation of a low-grade fever. Contrast-enhanced CT revealed an 18-cm tumor in the right lobe of the liver. The tumor was characterized by low-density areas suspected of cystic components, a high-density area suspected of hemorrhage, and contrast enhancement in the thickened marginal and internal septa. MRI revealed a high-intensity tumor with a heterogeneous structure on T2-weighted images. Angiosarcoma of the liver with intratumoral hemorrhage was suspected, and right hepatectomy was performed. The pathological diagnosis was an undifferentiated sarcoma based on the presence of undifferentiated mesenchymal tumor cells with a stellate to spindle-shaped pleomorphism. Following a multidisciplinary discussion, 4 courses of the AI regimen (doxorubicin and ifosfamide)were administered as adjuvant chemotherapy, and no recurrence was confirmed at 2 years and 6 months follow-up. Our case suggests that radical resection followed by adjuvant chemotherapy may contribute to a favorable prognosis for undifferentiated sarcoma of the liver.

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We present an optimization of Reverse NOE-pumping (RNP) in order to observe the 1H signals of ligands bound to proteins. Although various ligand-based NMR screening methods have been proposed, the most frequently used method has been Saturation-Transfer Difference (STD), owing to the relatively easy setup of experiments. Yet the critical point of STD is the selective irradiation of protein without irradiating ligand, and thus the STD technique is unable to observe 1H ligand signals, which resonate across the entire 1H spectral width. In the present study, the RNP experiment has been improved to develop an effective NMR-based screening technique. The optimized RNP spectra reveal less subtraction artifacts and phase distortion than the original RNP spectra, indicating its applicability to any type of ligand molecules.

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NMR screening methods based on 19F spin-spin relaxation time (19F-T2) were applied to fluorinated compounds bound to human serum albumin. Diflunisal and fleroxacin (the fluorinated compounds) contain two and three fluorine atoms per molecule, respectively, and are suitable as the model system for 19F NMR analysis. It was shown that 19F-T2 was more sensitive in monitoring the binding affinity to the target protein than 19F spin-lattice relaxation time (19F-T1). The comparisons of 19F signal intensities acquired at different echo times using 19F-T2 pulse sequence were also shown to be an effective means of assessing complex formation for fluorinated compounds.

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The 1H{19F} saturation transfer difference (STD) experiment presented here incorporates the WATERGATE W5 sequence to observe protein-ligand interactions in a human serum albumin (HSA)-fleroxacin complex. In conventional STD experiments, 1H of proteins are first saturated, and the ligands bound to these proteins are then observed. The method proposed here reverses this process: fluorine atoms in fleroxacin are selectively saturated, and saturation transfer then occurs to protons of fleroxacin as well as to those of HSA. The combined use of the present 1H{19F} STD and conventional STD methods is expected to provide better insight in the analysis of the role of fluorine atoms in a fluorinated compound.

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PURPOSE: The peripancreatic arterial system forms various arterial arcades and collateral branches; therefore, it stands to reason that the arterial supply into the pancreatic head region should be controlled as a whole peripancreatic arterial arcade rather than as the three major supplying arteries during isolated pancreatoduodenectomy (PD). We investigated the clinical importance of early control of the whole peripancreatic arterial arcade during PD. METHODS: The subjects of this retrospective study were 63 consecutive patients who underwent PD via a mesenteric approach at our hospital between October, 2014 and February, 2017. The patients were divided into an early control group (n = 27) and a late control group (n = 36) for comparative analysis. RESULTS: The peripancreatic arterial arcades and collateral branches were seen on preoperative multidetector row computed tomography (CT) images and during PD in all 63 patients. The early control group had significantly less intraoperative blood loss than the late control group. Early control of the whole peripancreatic arterial arcade was an independent factor associated with lower intraoperative blood loss in the multivariable analysis (P = 0.012). CONCLUSION: The arterial supply into the pancreatic head region should be controlled as a whole peripancreatic arterial arcade rather than as the three major supplying arteries during isolated PD.

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1H/31P NMR techniques were applied to analyze the binding mode of guanosine 2'-monophosphate (2'-GMP) to histone. To date, no structures of the complex comprising 2'-GMP and histone have been deposited in Protein Data Bank. Because the 31P nucleus can be a selective marker of phosphorylated compounds, the combined use of 1H and 31P NMR spectroscopy has been applied to investigate these molecular interactions. The complex formation was initially confirmed by 31P-diffusion ordered spectroscopy and 31P-T1 measurements. In 1H{1H} saturation transfer difference experiments, H2' and H3' signals of 2'-GMP were significantly attenuated, while the rest of the unexchangeable protons were observed, indicating that the contribution of H2' and H3' to the binding epitopes was low. The WaterLOGSY-type experiment with 31P detection also indicated that a phosphorylated group located close to H2' and H3' had little access to histone.

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BACKGROUND/AIM: Epithelial-to-mesenchymal transition (EMT) plays important roles in cancer progression. This study aimed to identify the exosomal miRNA (exo-miRNA) profiles related to the EMT status in pancreatic cancer (PC). MATERIALS AND METHODS: Comprehensive exo-miRNA-expression profiles in the culture media of PC cell lines were analyzed through microarray technology. The identified miRNAs were analyzed to investigate their clinical implication using The Cancer Genome Atlas (TCGA) dataset and clinical samples. RESULTS: We prioritized 291 exo-miRNAs differentially expressed between epithelial and mesenchymal cell types. Among them, survival analysis based on the TCGA dataset revealed that mir-196b and mir-204 significantly stratify the prognosis of PC cases. In addition, analysis of cell lines indicated miR-196b-3p as a mesenchymal marker and miR-204-3p as an epithelial marker. Finally, we demonstrated that miR-196b-3p and miR-204-3p in serum exosomes were differentially expressed among intraductal papillary mucinous neoplasms, mucinous cystic neoplasms, and PC. CONCLUSION: Serum exo-miRNA biomarkers potentially identify the pancreatic tumor status through less-invasive methods.

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1H/19F NMR-based screening methods were applied to a human serum albumin-fleroxacin complex. Fleroxacin contains three fluorine atoms in a molecule, which is suitable as a model fluorinated compound for NMR analysis with 1H and 19F detection. The 19F{1H} and 1H{1H} saturation transfer difference spectra were acquired and the 1H/19F spin-lattice relaxation rates were measured with and without any selective irradiation of protein resonance to identify the binding epitopes of fleroxacin. Because several 1H signals of fleroxacin resonated close to water, its precise signal intensities were unavailable. The 19F NMR-based screening methods successfully provide complementary information, indicating its importance in the analysis of fluorinated compounds.

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PURPOSE: This study aimed to explore the prognostic significance of the resection margin (R) status of pancreatic ductal adenocarcinoma (PDAC) patients receiving neoadjuvant therapy (NAT) or adjuvant chemotherapy (AC). METHODS: We retrospectively reviewed 427 consecutive patients, and the overall survival (OS) and disease-free survival (DFS) were analyzed based on the R status by a propensity score analysis (PSA). RESULTS: The R0 ratio of the NAT (+) group was significantly higher than that of the NAT (-) group (97.2% vs. 69.6%, P < 0.0001). Local recurrence was well controlled in the NAT (+) group compared to the NAT (-) group (15.3% vs. 34.1%, P = 0.0013). The PSA revealed no significant survival difference between R0 and R1 resection among those treated with AC (median survival time [MST]: 43.0 vs. 33.3 months, matching hazard ratio [HR]: 1.212, P = 0.5708). Furthermore, the DFS in R0 and R1 resection followed by AC was identical (MST: 20.6 vs. 17.7 months, matching HR: 1.020, P = 0.9482). CONCLUSIONS: NAT was a significant predictor of R0 resection. When patients completed AC, there were no marked differences in the OS or DFS between R0 and R1 resection. Our results demonstrated that the clinical impact of the R1 status has waned in the current era of PDAC management.

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Utilizing transglycosylation reaction catalyzed by ß- N -acetylhexosaminidase of Stenotrophomonas maltophilia , ß-D-fructofuranosyl-(2↔1)-α- N , N ´diacetylchitobioside (GlcNAc 2 -Fru) was synthesized from N -acetylsucrosamine and N , N ´-diacetylchitobiose (GlcNAc 2 ), and ß-D-fructofuranosyl-(2↔1)-α- N , N ´, N ´´-triacetylchitotrioside (GlcNAc 3 -Fru) was synthesized from GlcNAc 2 -Fru and GlcNAc 2 . Through purification by charcoal column chromatography, pure GlcNAc 2 -Fru and GlcNAc 3 -Fru were obtained in molar yields of 33.0 % and 11.7 % from GlcNAc 2 , respectively. The structures of these oligosaccharides were confirmed by comparing instrumental analysis data of fragments obtained by enzymatic hydrolysis and acid hydrolysis of them with known data of these fragments.

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AIM: This study aimed to assess the clinical utility of preoperative evaluation of liver fibrosis using platelet-albumin-bilirubin (PALBI) grade, Fibrosis-4 index (FIB-4), and aspartate transaminase-to-platelet ratio index (APRI) for hepatocellular carcinoma (HCC) patients and explore the clinical impact of these models with regard to perioperative risks and HCC prognosis. METHODS: Between January 2003 and December 2018, 305 consecutive patients who underwent hepatectomy for HCC were enrolled. RESULTS: The APRI showed the most robust diagnostic performance through each fibrosis stage among three models (PALBI, FIB-4, and APRI): fibrosis stage 3 (f3), area under the curve [AUC] = 0.55, 0.72, and 0.76; and f4, AUC = 0.51, 0.71, and 0.76, respectively). In addition, survival analysis revealed that all three models were significantly associated with HCC prognosis. PALBI (grade 1 vs. 2, 3): recurrence-free survival (RFS): median survival time (MST), 34 vs. 17 months, 0.007; overall survival (OS): MST, 115 vs. 68, 0.02. FIB-4 (grade 1, 2 vs. 3): RFS: MST, 34 vs. 22, 0.004, OS: MST, 120 vs. 63, 0.0001. APRI (grade 1, 2 vs. 3), RFS: MST, 30 vs. 20, 0.0005; OS: MST, 107 vs. 55, 0.0003. Among three scoring systems, only PALBI grade was significantly associated with both operative time (median, 303 vs. 340 min, 0.01) and intraoperative blood loss (median, 581 vs. 859 mL, 0.03). CONCLUSIONS: This study showed robust performances of selected liver reserve and fibrosis models to predict HCC prognosis. Of them, PALBI might be used for assessing perioperative risks for hepatectomy for HCC.

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BACKGROUND: This study aimed to evaluate novel resectability criteria for pancreatic ductal adenocarcinoma (PDAC) proposed by the International Association of Pancreatology (IAP) by comparing them with the National Comprehensive Cancer Network (NCCN) guidelines. METHODS: 369 patients who underwent upfront surgery for PDAC were retrospectively analyzed. Overall survival (OS) of each group as defined by either of the guidelines were compared and preoperative prognostic factors for OS were identified. RESULTS: Based on the IAP-criteria, 157 patients were classified as resectable (R), 192 as borderline resectable (BR) and 20 as unresectable (UR), with the median survival time (MST) of 40 months, 17 and 11, respectively. In contrast to the NCCN-criteria, BR demonstrated significantly better OS than UR (P = 0.023) under the IAP-criteria. Performance status ≥2 (hazard ratio [HR]: 2.47, P = 0.014) and lymph node metastasis suspected by imaging (HR: 1.55, P = 0.003) were identified as independent prognostic factors by the multivariate analysis along with portal or arterial invasion, while carbohydrate antigen 19-9 ≥ 500 U/ml was not (HR: 1.23, P = 0.190). CONCLUSION: The IAP-criteria, which includes biological and conditional factors, resulted in superior separation of survival curves stratified by the resectablity when compared with the NCCN-criteria.

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BACKGROUND: Neoadjuvant chemotherapy (NAC) has become the standard of care for resectable esophageal squamous cell carcinoma (ESCC) which is one of the most lethal cancers, to improve resectability and prognosis. On this basis, to provide individually optimized therapy for ESCC, a minimally-invasive biomarker for response to NAC is strongly desired. This study aimed to identify the miRNA signature in serum specimens taken from ESCC patients undergoing NAC through genome-wide microarray technology. METHODS: Comprehensive miRNA-expression profiles of serum specimens from ESCC patients before initial treatment were analyzed using microarray. A qPCR assay was performed to test the robustness of identified serum-based miRNA signature for discriminating response to NAC with serum specimens taken from 100 ESCC cases undergoing NAC. RESULTS: We prioritized 62 miRNAs differentially expressed between responders and non-responders (absolute log2 fold change > 1.0, corresponding P < 0.05) and from the 62 miRNAs, we selected the miR-23a-5p, miR-193b-5p, and miR-873-3p, which were highly expressed in non-responders. Following qPCR analysis indicated the expression of miR-193b-5p and miR-873-3p in serum specimens were significantly higher in non-responders among three selected miRNAs (P = 0.004 and 0.001, respectively). Subsequently, we developed 2-miR-model (miR-193b-5p and miR-873-3p), 3-miR-model, and 2-miR + lymphatic invasion (ly) model based on logistic regression analysis, which achieved the better area under the receiver operating characteristic curves than those of single miRNAs as 2-miR-model, 0.70 (95% CI 0.57 to 0.82); 3-miR-model, 0.70 (95% CI 0.57 to 0.83); and 2-miR + ly, 0.73 (95% CI 0.60-0.86), respectively. Furthermore, we compared the detective power of the combined model: 2-miR + ly for discriminating non-responders to NAC, to other pretreatment clinical features. Consequently, 2-miR + ly model was superior to serum SCC antigen with great significance (P = 0.01) and to ly, and clinical T stage with marginal significance (P = 0.18, 0.07, respectively). CONCLUSIONS: Collectively, we demonstrated that the potential of a multi-miRNA biomarker for identifying NAC response in ESCC is realistic, and can be used in the clinic with the further validation.

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OBJECTIVES: This study aimed to clarify the correlation between image classification and the pathological degree of portal system invasion (PSI) and to evaluate the prognostic impact of PSI in pancreatic cancer (PC). METHODS: Pancreatic cancer patients with surgical resections (head, n = 244; body and tail, n = 80) were enrolled in this study. RESULTS: Based on imaging findings, portal vein (PV) invasion was classified as type A (absent), B (unilateral narrowing), C (bilateral narrowing), or D (stenosis or obstruction with collaterals). Splenic vein (SPV) invasion was classified as type α (absent), ß (stenosis), or γ (obstruction). The pathological grade of venous invasion was classified as grade 0 (no invasion), 1 (tunica adventitia), 2 (tunica media), or 3 (tunica intima). In PV and SPV invasions, image classification and pathological grade showed significant correlation (PV: ρ = 0.696; SPV: ρ = 0.681). Patients with PV invasion deeper than type B exhibited significantly poorer survival than type A (P < 0.0001). In contrast, there was no difference in survival among types α, ß, and γ. CONCLUSIONS: Image classification was correlated with the pathological grade of PSI in PC. Although not applicable for SPV invasion, image classification of PV invasion is a robust indicator for PC prognosis.

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BACKGROUND: The association between neoadjuvant therapy (NAT) and nutritional status in pancreatic cancer (PC) is unknown. OBJECTIVE: The aim of this study was to assess the impact of NAT on nutritional status. METHODS: Overall, 161 patients who underwent pancreatoduodenectomy for PC between August 2010 and March 2017 were enrolled and were divided into two groups: the neoadjuvant group (NAG; n = 67) and the control group (CG; n = 94). Based on relative dose intensity (RDI), patients in the NAG group were further divided into RDI ≥ 80% (n = 39) and RDI < 80% (n = 19). Changes in nutritional index, inflammatory index, and inflammation-based prognostic scores during NAT and the perioperative period were assessed. RESULTS: Retinol-binding protein, prealbumin, neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, and prognostic nutrition index significantly worsened in the NAG after NAT (p = 0.007, p = 0.03, p = 0.04, p = 0.007, and p = 0.004, respectively). The recovery of rapid turnover proteins after postoperative day 5 was significantly worse in the NAG compared with the CG (p < 0.05), but tended to be more prompt in the RDI ≥ 80% group among the NAG. There was no significant difference in the incidence of postoperative complications, length of hospital stay, and time to postoperative adjuvant therapy between the NAG and the CG. CONCLUSIONS: NAT for PC could aggravate nutritional status and hamper its postoperative recovery. Furthermore, malnutrition might decrease tolerance of NAT. These findings suggest the importance of nutritional support for patients with NAT in PC.

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Natural products such as polyketides often possess various spin systems, consisting of a methine group directly bonded to a methyl group (e.g., ─CHA ─CHB (CH3 )─CHC ─). The methine proton HB splits into a broadened multiplet by coupling with several vicinal protons, rendering analysis difficult of n JH-H with respect to HB in double-quantum filtered COSY or exclusive COSY. For the purpose of measuring n JH-H in the aforesaid spin system, we have developed new techniques, named multifrequency homo-decoupling (MDEC)-J-resolved COSY and DPFGSE-MDEC-J-resolved COSY. This method incorporates MDEC pulse scheme into J-resolved COSY for the selective decouple of individual methyl groups, avoiding decoupling of the target protons resonating in methyl region. Determinations of n JH-H of the multiplet signals can easily be performed using the proposed pulse sequence.

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Using d-glucurono-6,3-lactone (GlcL) and sucrose (Suc) as raw materials, we synthesized sucuronic acid (SucA), in which the d-glucose (Glc) residue of Suc was replaced with d-glucuronic acid, by a three-step chemoenzymatic method. In the 1st chemical step, methyl d-glucuronate (GlcAM) was synthesized by treating GlcL with a strong base anion exchange resin, Amberlite IRA402BL OH AG, in anhydrous methanol. In the 2nd step, which included an enzyme reaction, methyl sucuronate (SucAM) was synthesized from GlcAM and fructose by exploiting the transfructosylation activity of the Microbacterium saccharophilum K-1 ß-fructofuranosidase, a reaction that is suppressed in the presence of high-concentration Glc. In this reaction, the addition of a Suc-non-assimilating yeast, Saccharomyces bisporus NBRC1131, to the reaction mixture increased the amount of SucAM generated, because Glc was removed from the mixture by this yeast. In the 3rd chemical step for producing sodium sucuronate (SucA·Na), SucAM was treated with Amberlite IRA402BL OH AG in water to hydrolyze SucAM's ester bond, and product was then treated with NaOH. The molar yield of SucA·Na from GlcL was 34.2%. SucA was stable at 37 °C in buffer solutions at pH 3, 5, 7, or 9. However, at temperatures exceeding 75 °C, the glycosidic bond of this disaccharide was hydrolyzed not only in acidic buffers (pH 3 and 5) but also in alkaline buffer (pH 9). SucA was not a suitable substrate for the ß-fructofuranosidases of M. saccharopilum K-1 and Saccharomyces cerevisiae.

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Two kinds of oligosaccharides, N-acetylraffinosamine (RafNAc) and N-acetylplanteosamine (PlaNAc), were synthesized from N-acetylsucrosamine and melibiose using the transgalactosylation activity of Aspergillus niger α-galactosidase. RafNAc and PlaNAc are novel trisaccharides in which d-glucopyranose residues in raffinose (Raf) and planteose are replaced with N-acetyl-d-glucosamine. These trisaccharides were more stable in acidic solution than Raf. RafNAc was hydrolyzed more rapidly than Raf by α-galactosidase of green coffee bean. In contrast, RafNAc was not hydrolyzed by Saccharomyces cerevisiae invertase, although Raf was hydrolyzed well by this enzyme. These results indicate that the physicochemical properties and steric structure of RafNAc differ considerably from those of Raf.

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Subtilisin-like proteases are broadly expressed in organisms ranging from bacteria to mammals. During maturation of these enzymes, N-terminal propeptides function as intramolecular chaperones, assisting the folding of their catalytic domains. However, we have identified an exceptional case, the serine protease from Aeromonas sobria (ASP), that lacks a propeptide. Instead, ORF2, a protein encoded just downstream of asp, appears essential for proper ASP folding. The mechanism by which ORF2 functions remains an open question, because it shares no sequence homology with any known intramolecular propeptide or other protein. Here we report the crystal structure of the ORF2-ASP complex and the solution structure of free ORF2. ORF2 consists of three regions: an N-terminal extension, a central body, and a C-terminal tail. Together, the structure of the central body and the C-terminal tail is similar to that of the intramolecular propeptide. The N-terminal extension, which is not seen in other subtilisin-like enzymes, is intrinsically disordered but forms some degree of secondary structure upon binding ASP. We also show that C-terminal (ΔC1 and ΔC5) or N-terminal (ΔN43 and ΔN64) deletion eliminates the ability of ORF2 to function as a chaperone. Characterization of the maturation of ASP with ORF2 showed that folding occurs in the periplasmic space and is followed by translocation into extracellular space and dissociation from ORF2, generating active ASP. Finally, a PSI-BLAST search revealed that operons encoding subtilases and their external chaperones are widely distributed among Gram-negative bacteria, suggesting that ASP and its homologs form a novel family of subtilases having an external chaperone.

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The (1)H-(19) F heteronuclear NMR experiments were achieved using the conventional spectrometer equipped with a single high band amplifier and a (1)H/(19)F/(13) C double-tuned probe. Although double high band amplifiers are generally required to perform such experiments, a simple modification of pathway in the conventional spectrometer was capable of acquiring various (1)H-(19)F heteronuclear spectra. The efficiency of the present technique was demonstrated in an application for (19)F{(1)H} and (1)H{(19)F} saturation transfer difference experiments.

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