Differential Diagnosis of Solid Pancreatic Lesions Using Detective Flow Imaging Endoscopic Ultrasonography.

The differential diagnosis of solid pancreatic lesions (SPLs) using B-mode endoscopic ultrasonography (EUS) is challenging. Detective flow imaging (DFI) offers the potential for detecting low-flow vessels in the pancreas, thus enhancing diagnostic accuracy. This retrospective study aimed to investigate DFI-EUS findings of SPLs and analyze their differential diagnostic accuracy for pancreatic cancer. We included 104 patients with pathologically confirmed SPLs who underwent EUS between April 2021 and June 2023. Expert endosonographers, blinded to the patients' clinical data, evaluated images obtained through B-mode, eFLOW, and DFI-EUS. The frame rate and vessel detection sensitivity were compared between eFLOW and DFI, and the diagnostic criteria for pancreatic cancer were established. The visualization rate for vessels in SPLs was significantly higher with DFI-EUS (96%) compared to eFLOW (27%). Additionally, DFI showed a superior frame rate, sensitivity (99%), and accuracy (88%) for detecting pancreatic cancer, although with a modest specificity (43%). On DFI-EUS, characteristics such as hypovascularity, peritumoral vessel distribution, or spotty vessel form were suggestive of pancreatic cancer. DFI-EUS significantly improved the visualization of vascular structures within the SPLs, highlighting its efficacy as a diagnostic modality for pancreatic cancer.

Novel peroral cholangioscopy-guided electrohydraulic lithotripsy for difficult stones.

Miwa and colleagues report on their experience with a newly developed peroral cholangioscope that is effective for the removal of difficult stones in the common bile duct and the cystic duct. The scope offers a large working channel and a high mobility bending section, increasing the efficacy of electrohydraulic lithotripsy.

Pancreatic duct lavage cytology combined with a cell-block method for patients with possible pancreatic ductal adenocarcinomas, including pancreatic carcinoma in situ.

BACKGROUND/AIMS: This study aimed to clarify the efficacy and safety of pancreatic duct lavage cytology combined with a cell-block method (PLC-CB) for possible pancreatic ductal adenocarcinomas (PDACs). METHODS: This study included 41 patients with suspected PDACs who underwent PLC-CB mainly because they were unfit for undergoing endoscopic ultrasonography-guided fine needle aspiration. A 6-Fr double lumen catheter was mainly used to perform PLC-CB. Final diagnoses were obtained from the findings of resected specimens or clinical outcomes during surveillance after PLC-CB. RESULTS: Histocytological evaluations using PLC-CB were performed in 87.8% (36/41) of the patients. For 31 of the 36 patients, final diagnoses (invasive PDAC, 12; pancreatic carcinoma in situ, 5; benignancy, 14) were made, and the remaining five patients were excluded due to lack of surveillance periods after PLC-CB. For 31 patients, the sensitivity, specificity, and accuracy of PLC-CB for detecting malignancy were 94.1%, 100%, and 96.8%, respectively. In addition, they were 87.5%, 100%, and 94.1%, respectively, in 17 patients without pancreatic masses detectable using endoscopic ultrasonography. Four patients developed postprocedural pancreatitis, which improved with conservative therapy. CONCLUSION: PLC-CB has an excellent ability to detect malignancies in patients with possible PDACs, including pancreatic carcinoma in situ.

Loop technique for guidewire manipulation during endoscopic ultrasound-guided hepaticogastrostomy.

Background and Aim: Endoscopic ultrasound-guided hepaticogastrostomy (EUS-HGS) is widely used in the management of biliary obstructions; however, literature on guidewire manipulation is lacking. This study aimed to assess the utility and optimal conditions of the loop technique for guidewire manipulation during EUS-HGS. Methods: Consecutive patients who underwent EUS-HGS between April 2015 and January 2022 were included in this study. Patient characteristics and procedural details were retrospectively analyzed. Guidewire manipulations were classified as conventional technique or loop technique, based on the shape of the guidewire tip. Results: A total of 52 patients (Median age: 73 years, 38 male and 14 female) underwent EUS-HGS. The median guidewire insertion time was 49 s and the median overall procedure time was 20.5 min. The initial guidewire direction was toward the peripheral side in 23 patients (44%). Technical success rate of the EUS-HGS was 100%. Twenty patients (38%) underwent the procedure using the loop technique and 32 (62%) with the conventional technique. In the logistic regression analysis, an angle between the bile duct and needle of >70° was independently associated with use of the loop technique (OR 9.84; 95% CI: 2.24-43.13; P <0.01). Conclusion: This study revealed the utility of the loop technique in EUS-HGS. This technique is recommended if the bile duct is punctured at an angle >70°.

Mixed neuroendocrine-non-neuroendocrine neoplasm with mucinous adenocarcinoma and amphicrine carcinoma components in the bile duct: an autopsy case.

We report the first case of bile duct mixed neuroendocrine-non-neuroendocrine neoplasm (MiNEN) that had a mucinous carcinoma component. An 88-year-old man with biliary obstruction was diagnosed as having distal bile duct cancer using imaging examinations and endoscopic biopsy. The patient received the best supportive care without surgical resection for 13 months until death. An autopsy revealed a bulky mass involving the distal bile duct and multiple metastases in intra-abdominal lymph nodes, the liver, and the lungs. The primary cancer was microscopically diagnosed as a MiNEN, which consisted of mucinous adenocarcinoma and large cell-type neuroendocrine carcinoma (NEC) components. Metastatic lesions in the liver and lungs were composed of only NEC with rich extracellular mucin without adenocarcinoma cells. Using electron microscopy and immunohistochemistry, it was proved that all NEC cells in both primary and metastatic lesions had amphicrine features. On the basis of pathological findings, we thought that the MiNEN was initially derived from a mucinous adenocarcinoma that dedifferentiated to amphicrine NEC cells with mucin production.

A highly photostable and bright green fluorescent protein.

The low photostability of fluorescent proteins is a limiting factor in many applications of fluorescence microscopy. Here we present StayGold, a green fluorescent protein (GFP) derived from the jellyfish Cytaeis uchidae. StayGold is over one order of magnitude more photostable than any currently available fluorescent protein and has a cellular brightness similar to mNeonGreen. We used StayGold to image the dynamics of the endoplasmic reticulum (ER) with high spatiotemporal resolution over several minutes using structured illumination microscopy (SIM) and observed substantially less photobleaching than with a GFP variant optimized for stability in the ER. Using StayGold fusions and SIM, we also imaged the dynamics of mitochondrial fusion and fission and mapped the viral spike proteins in fixed cells infected with severe acute respiratory syndrome coronavirus 2. As StayGold is a dimer, we created a tandem dimer version that allowed us to observe the dynamics of microtubules and the excitatory post-synaptic density in neurons. StayGold will substantially reduce the limitations imposed by photobleaching, especially in live cell or volumetric imaging.

Cholangioscopy- versus fluoroscopy-guided transpapillary mapping biopsy for preoperative evaluation of extrahepatic cholangiocarcinoma: a prospective randomized crossover study.

BACKGROUND: To evaluate the lateral extent of extrahepatic cholangiocarcinoma, the value of cholangioscopy-guided mapping biopsy (CMB) compared with that of fluoroscopy-guided mapping biopsy (FMB) remains unknown. The aim of this study was to compare these two techniques. METHODS: In this prospective, randomized, crossover study, both CMB and FMB techniques were performed for all patients in a randomized order. Target sites for the mapping biopsy were determined based on resection lines of possible surgical procedures. At least two biopsy strokes were attempted at each target site. The primary outcome was the rate of site-based successful biopsies, which was defined as acquisition of epithelium-containing material appropriate for diagnosing benignancy/malignancy from each site, regardless of amount of materials obtained from the same site. RESULTS: Between September 2016 and October 2018, 28 patients (16 distal bile duct cancer and 12 perihilar bile duct cancer) were enrolled and divided into two groups of 14 patients: CMB first and FMB first. Although all 118 target sites could be approached using CMB, FMB forceps reached only 71% of them with significantly poor accessibility to the B2/3 confluence. Since several materials were too small and did not contain epithelium, the overall rates of site-based successful biopsies were 78% (92/118) using CMB and 64% (76/118) using FMB (P = 0.031). CONCLUSIONS: The rate of site-based successful biopsies using CMB was significantly higher than that using FMB when evaluated using specimens obtained from several biopsy strokes.

Safety and Recipient Satisfaction of Propofol Sedation in Outpatient Endoscopy: A 24-Hour Prospective Investigation Using a Questionnaire Survey.

BACKGROUND/AIMS: The aim of this study was to evaluate the safety of sedation with propofol as an alternative to benzodiazepine drugs in outpatient endoscopy. METHODS: In this prospective study, examinees who underwent outpatient endoscopy under propofol sedation and submitted a nextday questionnaire with providing informed consent were evaluated. Periprocedural acute responses, late adverse events within 24 hours, and examinee satisfaction were evaluated. RESULTS: Among the 4,122 patients who received propofol in the 17,978 outpatient-based endoscopic examinations performed between November 2016 and March 2018, 2,305 eligible examinees (esophagogastroduodenoscopy for 1,340, endoscopic ultrasonography for 945, and total colonoscopy for 20) were enrolled, and their responses to a questionnaire were analyzed. The mean propofol dose was 69.6±24.4 mg (range, 20-200 mg). Diazepam, midazolam, and/or pentazocine in combination with propofol was administered to 146 examinees. Mild oxygen desaturation was observed in 59 examinees (2.6%); and mild bradycardia, in 2 (0.09%). Other severe reactions or late events did not occur. After eliminating 181 invalid responses, 97.7% (2,065/2,124) of the patients desired propofol sedation in future examinations. CONCLUSION: Propofol sedation was found to be safe-without severe adverse events or accidents-for outpatient endoscopy on the basis of the patients' next-day self-evaluation. Given the high satisfaction level, propofol sedation might be an ideal tool for painless endoscopic screening.

Value of repeated cytology for intraductal papillary mucinous neoplasms of the pancreas with high risk potential of malignancy: Is it a promising method for monitoring a malignant transformation?

OBJECTIVES: The efficacy of and indications for cytological reexamination to detect malignant changes in branch duct type intraductal papillary mucinous neoplasms (BD-IPMNs) have not been studied in detail. We conducted a retrospective study to evaluate the efficacy and indications of cytological reexamination by using pancreatic juice (repeated cytology) for BD-IPMNs. METHODS: Forty-five patients who underwent repeated cytology after a diagnosis of benignancy by using initial cytology were recruited for this study. RESULTS: Thirty-eight patients, excluding 7 patients with lack of surveillance period after the final cytology, were classified into Malignancy (n = 13) and Benignancy groups (n = 25) on the bases of the findings from resected specimens or changes in BD-IPMNs after repeated cytology. The sensitivity and specificity to detect malignant changes in BD-IPMNs by using repeated cytology were 62% and 100%, respectively. For the 12 patients with mural nodules (MNs) ≥ 5 mm (67% of them were malignant), the sensitivity was 50%, whereas, for the 26 patients without MNs ≥ 5 mm (19% of them were malignant), it was 80%. In addition, malignant changes in BD-IPMNs after initial cytology occurred in 62% of the patients with changes in the MNs and 27% of the patients with an increase in the cyst size. CONCLUSION: Repeated cytology can play a role in the determination for surgery even after a diagnosis of benignancy by using initial cytology, especially for BD-IPMNs without MNs ≥5 mm. In addition, changes in the MNs or cyst size may be appropriate indications for repeated cytology.

Peroral Cholangioscopy-guided Electrohydraulic Lithotripsy with a SpyGlass DS Versus a Conventional Digital Cholangioscope for Difficult Bile Duct Stones.

Objective Recently, a new digital peroral cholangioscopy (POCS) system, the SpyGlass DS (SpyDS), has been used for POCS-guided lithotripsy for difficult bile duct stones (DBDSs). The aim of this retrospective study was to compare the efficacy of SpyDS-guided electrohydraulic lithotripsy (EHL) for DBDS with that of a conventional digital cholangioscope. Methods Seventeen consecutive patients who had undergone POCS-guided EHL for DBDS with the SpyDS between October 2015 and January 2019 were enrolled in this study group (SpyDS group) using a prospectively maintained database. Fifteen other consecutive patients who had undergone POCS-guided EHL with a conventional digital cholangioscope (CHF-B260) just prior to the introduction of the SpyDS between December 2006 and September 2015 were analyzed as a control group (CHF group). The main outcome measurement was the total procedure time to complete stone removal. Results The rate of complete stone removal was 100% for both groups. The mean total procedure time for the SpyDS group was significantly shorter than that for the CHF group (67±30 minutes vs. 107±64 minutes, p=0.038). The mean number of endoscopic sessions for the SpyDS group was significantly lower than that for the CHF group (1.35±0.49 vs. 2.00±0.85, p=0.037). There were no significant differences in the rate of adverse events between the two groups. Conclusion The SpyDS appears useful for decreasing the procedure time and number of endoscopic sessions for complete stone removal in POCS-guided EHL for DBDS compared with a conventional digital cholangioscope.

Long-term Outcomes of Endoscopic Papillary Large-balloon Dilation for Common Bile Duct Stones.

Objective Endoscopic papillary large-balloon dilation (EPLBD) for common bile duct (CBD) stone removal has been confirmed to be safe and effective in the short term. The long-term outcomes of EPLBD, which have not been sufficiently evaluated, were therefore investigated in this study. Methods For patients who had undergone endoscopic CBD stone removal with EPLBD between October 2011 and December 2015, follow-up surveys were conducted using a postal survey, telephone interview, or medical record review in August 2017. The main outcome measurement was the recurrence rate of CBD stones after complete stone removal with EPLBD in patients who received follow-up for more than one year. Risk factors for such recurrence were secondarily analyzed. Results Of the 98 patients treated using EPLBD, 93 (95%) were followed up after complete stone removal and analyzed for the long-term outcomes. During the mean follow-up period of 33.7±16.6 months, CBD stones recurred in 16 patients (17%) with a mean interval of 12.7±12.7 months. Univariate analyses showed that a large stone size, multiple stones, a large distal CBD diameter, and a history of cholecystectomy were significant risk factors for stone recurrence (p=0.022, 0.013, 0.001 and 0.035, respectively). The large distal CBD diameter was the only significant risk factor for stone recurrence in a multivariate analysis (hazard ratio, 1.227; p=0.031). Conclusion The long-term outcomes of EPLBD for CBD stones, including the rate of stone recurrence, were found to be acceptable. A large distal CBD diameter was an independent risk factor for stone recurrence.

Analysis of skeletal-muscle condition after excessive loading of the lower legs by sequential magnetic resonance imaging.

OBJECTIVES: To determine the changes of muscle conditions of lower leg after stretch shortening cycle exercises by MRI. SUBJECTS AND METHODS: This study included 20 healthy male adult volunteers. After conducting control MRI, each subject performed 3 sets of exercise loading, each set consisting of 100 repetitions of rebound jumping on one foot. MRIs were performed immediately after exercise loading (0 h), 6, 30, and 168 h later. After constructing T1/T2/Fractional Anisotropy (FA)/Apparent Diffusion Coefficient (ADC) maps, the changes of three skeletal muscles of the leg (the tibialis anterior [TA], soleus [SOL], and gastrocnemius [GA]) were quantitatively evaluated in each map at each time point. RESULTS: The T1 and T2 values were prolonged after exercise loading, and there was a delay in the recovery of T1 at 6 and 30 h after exercise loading, as compared to those of T2 values over time. The ADC values were elevated in all three muscles immediately after exercise loading, then recovered more slowly than T1 and T2, and still had not returned to baseline 168 h after exercise loading. The FA value decreased in all three muscles after exercise loading, with the greatest decrease occurring immediately after exercise loading. As with the ADC values, the FA values were slow to recover from the decrease, and had not returned to baseline levels 168 h post-loading. CONCLUSION: The delay of T1 value recovery suggested that the T1 value may reflect the muscle condition like fatigue and damage. Changes in the ADC and FA values over time suggested that structural changes such as minute muscular injuries can be detected by diffusion-weighted MRI. Meanwhile, the changes observed in the T1 and T2 values suggested that the measured relaxation time data reflected not only the water volume in the muscle, but also the muscle condition after exercise loading.

8-Substituted 2-alkynyl-N(9)-propargyladenines as A2A adenosine receptor antagonists.

Structure-activity relationships of 2-alkynyladenine derivatives were explored by varying substituents at the 9-, 8- and 2-positions of the purine moiety in order to optimize A2A adenosine receptor antagonist activity in vitro. A propargyl group at the 9-position was found to be important for A2A antagonist activity, and the introduction of a halogen, aryl, or heteroaryl at the 8-position further enhanced activity. A series of 8-substituted 2-alkynyl-N(9)-propargyladenine derivatives exhibited potent antagonist activity, with IC50 values in the low nM range. Compound 4a from this series was found to be orally active at a dose of 3 mg/kg in a mouse catalepsy model and a 6-hydroxydopamine-lesioned rat model of Parkinson's disease.

Effects of cytidine 5'-diphosphocholine (CDP-choline) on the thermal nociceptive threshold in streptozotocin-induced diabetic mice.

Neuropathy accompanied by abnormal sensory perception is the most common complication in insulin-dependent and -independent diabetes mellitus. Since there are very few effective therapeutic regimens for sensory abnormalities in diabetes, we examined the effect of cytidine 5'-diphosphocholine (CDP)-choline on the thermal nociceptive threshold in streptozotocin-induced diabetic mice using the tail-flick test. Diabetic mice showed a shorter tail-flick latency at 1-4 weeks after streptozotocin treatment and a longer tail-flick latency after 8-12 weeks. This hyper- and hypoalgesia in diabetic mice was almost completely inhibited by daily treatment with CDP-choline (100 mg/kg/day, p.o.) beginning on the day of streptozotocin treatment. Daily treatment with CDP-choline beginning 5 weeks after streptozotocin treatment attenuated the development of hypoalgesia. Diabetic mice showed a significant increase in Na(+)-K(+)-ATPase activity at 3 weeks after streptozotocin treatment, whereas Na(+)-K(+)-ATPase activity was decreased at 12 weeks after treatment. These alterations were normalized by daily treatment with CDP-choline (100 mg/kg/day, p.o.) beginning the day of streptozotocin treatment. These results provide evidence to support the therapeutic potency of CDP-choline on the development of thermal hyper- and hypoalgesia and the progression of thermal hypoalgesia in diabetic mice. Moreover, these effects of CDP-choline may result from the normalization of Na(+)-K(+)-ATPase activity.

Diabetes-related changes in contractile responses of stomach fundus to endothelin-1 in streptozotocin-induced diabetic rats.

The contractile response of the stomach fundus to endothelin-1 (ET-1) was examined in streptozotocin (STZ)-induced diabetic rats. In STZ-diabetic rats (versus age-matched control rats) (a) ET-1 caused a longer-lasting contraction of stomach fundus strips, and (b) in the dose-response curve, the ET-1-induced contraction was significantly greater for a given concentration (3 x 10(-7) to 10(-7) M). Although repeated application of ET-1 led to desensitization, the desensitization was less pronounced in STZ-diabetic rats than in the controls. The density of the binding sites for [(125)I]-ET-1 was increased in the diabetic stomach fundus (versus the controls), but Kd values were similar between the two groups. The ET(B) receptor mRNA expression level was significantly increased in the diabetic stomach fundus. These results suggest that the diabetes-related enhancement of the ET-1-induced contraction of the stomach fundus may be due to an increase in the ET(B) receptor population.