Inside stent placement is suitable for preoperative biliary drainage in patients with perihilar cholangiocarcinoma.

BACKGROUND/PURPOSE: Endoscopic biliary stenting (EBS) is commonly used for preoperative drainage of localized perihilar cholangiocarcinoma (LPHC). This study retrospectively compared the utility of inside stent (IS) and conventional stent (CS) for preoperative EBS in patients with LPHC. METHODS: EBS was performed in 56 patients with LPHC. EBS involved the placement of a CS (n = 32) or IS (n = 24). Treatment outcomes were compared between these two groups. RESULTS: Preoperative recurrent biliary obstruction (RBO) occurred in 23 patients (71.9%) in the CS group and 7 (29.2%) in the IS group, with a significant difference (p = 0.002). The time to RBO (TRBO) was significantly longer in IS than in CS (log-rank: p < 0.001). The number of stent replacements was significantly lower in IS than CS [0.38 (0-3) vs. 1.88 (0-8), respectively; p < 0.001]. Gemcitabine-based neoadjuvant chemotherapy (NAC) was administered to 26 patients (46.4%). Among patients who received NAC, TRBO was longer in IS than in CS group (log-rank: p < 0.001). The IS group had a significantly shorter preoperative and postoperative hospital stay than the CS group (20.0 vs. 37.0 days; p = 0.024, and 33.5 vs. 41.5 days; p = 0.016).　 Both the preoperative and the postoperative costs were significantly lower in the IS group than in the CS group (p = 0.049 and p = 0.0034, respectively). CONCLUSION: Compared with CS, IS for preoperative EBS in LPHC patients resulted in fewer complications and lower re-intervention rates. The fact that the IS group had shorter preoperative and postoperative hospital stays and lower costs both preoperatively and postoperatively compared to the CS group may suggest that the use of IS has the potential to benefit not only the patient but also the healthcare system.

The Diagnosis of Esophageal Tuberculosis Through an Endoscopic Ultrasound-guided Fine-needle Aspiration Biopsy: A Case Study.

A 54-year-old woman presented with an elevated esophageal lesion. Computed tomography (CT) and magnetic resonance imaging revealed a mass in the pancreatic head. Endoscopic ultrasound (EUS) showed a well-defined, round, hypoechoic mass, which was considered lymph node enlargement. An EUS-guided fine-needle aspiration biopsy (FNAB) was performed on the esophagus and the mass above the pancreatic head. The pathologically confirmed epithelial cells and multinucleated giant cells were positive for T-SPOT. Clinically, tuberculous lymphadenitis and esophageal tuberculosis were suspected, with successful treatment with anti-tuberculosis therapy resulting in a good response. Our findings suggest that an EUS-FNAB is useful for diagnosing esophageal tuberculosis.

Isolated pancreatic metastasis from malignant melanoma: a case report and literature review.

Isolated pancreatic metastasis from malignant melanoma is rare. Pancreatic metastasis is difficult to diagnose in patients with unknown primary malignant melanoma. Endoscopic ultrasound-guided fine-needle aspiration plays an important role in confirming the diagnosis. A 67-year-old woman was referred to our institution because of a mass in her pancreas. Computed tomography and magnetic resonance imaging revealed a 35-mm mass localized on the pancreatic tail, with low attenuation, surrounded by a high-attenuation rim. Endoscopic ultrasonography revealed a hypoechoic mass with central anechoic areas. Endoscopic ultrasound-guided fine-needle aspiration of the mass was performed, and the pathological diagnosis was malignant melanoma. Intense fluorodeoxyglucose uptake was observed in the pancreatic tail on positron emission tomography-computed tomography. No other malignant melanoma was found. Distal pancreatectomy was performed. Six months postoperatively, positron emission tomography-computed tomography revealed high uptake in the left nasal cavity, and biopsy revealed the mass to be a malignant melanoma, indicating that the primary site of the malignant melanoma was the left nasal cavity and that the pancreatic mass and peritoneal lesion were metastases. The patient had survived > 2 years after the distal pancreatectomy. Pancreatic resection of isolated pancreatic metastasis can possibly prolong survival; however, metastatic melanoma usually has poor prognosis.

Strangeness contribution to the proton spin from lattice QCD.

We compute the strangeness and light-quark contributions Δs, Δu, and Δd to the proton spin in n(f)=2 lattice QCD at a pion mass of about 285 MeV and at a lattice spacing a≈0.073 fm, using the nonperturbatively improved Sheikholeslami-Wohlert Wilson action. We carry out the renormalization of these matrix elements, which involves mixing between contributions from different quark flavors. Our main result is the small negative value Δs(MS)(√(7.4) GeV)=-0.020(10)(4) of the strangeness contribution to the nucleon spin. The second error is an estimate of the uncertainty, due to the missing extrapolation to the physical point.

Weak gel of chitin with ionic liquid, 1-allyl-3-methylimidazolium bromide.

This paper reports the formation of weak gel of chitin with an ionic liquid, 1-allyl-3-methylimidazolium bromide (IL). When a mixture of 5% (w/w) chitin with IL was heated at 100 degrees C for 48h, the clear liquid was obtained. The experimental process was observed by the CCD camera view and the SEM analysis. From a mixture of chitin with IL in the higher concentration (7%, w/w), a more viscous material, i.e., a gel-like material was obtained. The rheological evaluations showed that both 5% (w/w) and 7% (w/w) chitins with IL behaved as weak gels.

Nucleon distribution amplitudes from lattice QCD.

We calculate low moments of the leading-twist and next-to-leading-twist nucleon distribution amplitudes on the lattice using two flavors of clover fermions. The results are presented in the MS[over ] scheme at a scale of 2 GeV and can be immediately applied in phenomenological studies. We find that the deviation of the leading-twist nucleon distribution amplitude from its asymptotic form is less pronounced than sometimes claimed in the literature.

High-speed three-dimensional human retinal imaging by line-field spectral domain optical coherence tomography.

Line-field spectral domain optical coherence tomography (LF-SDOCT) has been developed for very high-speed three-dimensional (3D) retinal imaging. By this technique, the A-line rate significantly improved to 823,200 A-lines/s for single frame imaging and 51,500 A-lines/s for continues frame imaging. The frame rate at continues frame imaging is 201 fps. This 3D acquisition speed is more than two fold higher acquisition speed than the standard flying spot SD-OCT. In this paper, the integration time of the camera was optimized for the in vivo retinal measurement and the degradation of the lateral resolution due to the ocular aberrations was suppressed by introducing the pupil stop. Owing to an optimal integration time, the motion artifact can be significantly suppressed. Also a pupil stop was employed in order to enhance the contrast of the OCT image for the effect of ocular aberrations. The in vivo 3D retinal imaging with 256 cross-sectional images (256 A-lines/image) was successfully performed in 1.3 seconds, corresponding to 0.8 volume/s. The maximum on-axis system sensitivity was measured to be 89.4 dB at a depth of 112 mum with an axial resolution of 7.4 mum in tissue. It is shown that LF-SDOCT might have a sensitivity advantage in comparison to the flying spot SD-OCT in the ultra high-speed acquisition mode.

Non-iterative numerical method for laterally superresolving Fourier domain optical coherence tomography.

A numerical deconvolution method to cancel lateral defocus in Fourier domain optical coherence tomography (FD-OCT) is presented. This method uses a depth-dependent lateral point spread function and some approximations to design a deconvolution filter for the cancellation of lateral defocus. Improved lateral resolutions are theoretically estimated; consequently, the effect of lateral superresolution in this method is derived. The superresolution is experimentally confirmed by a razor blade test, and an intuitive physical interpretation of this effect is presented. The razor blade test also confirms that this method enhances the signal-to-noise ratio of OCT. This method is applied to OCT images of medical samples, in vivo human anterior eye segments, and exhibits its potential to cancel the defocusing of practical OCT images. The validity and restrictions involved in each approximation employed to design the deconvolution filter are discussed. A chromatic and a two-dimensional extensions of this method are also described.

Standard and line-field fourier domain optical coherence tomography.

Standard Fourier domain optical coherence tomography (FD-OCT) and line-field Fourier domain optical coherence tomography (LF-FDOCT) are described. The standard FD-OCT has the measurement speed of 36 frames/sec and one frame consisting 500 A-scans. The LF-FDOCT is an improved version of FD-OCT and determines a cross section of a sample without any mechanical scanning. The LF-FDOCT has the measurement speed of 30 frames/sec, which is corresponding to 480 KH/ A-scan. A galvano-meter is introduced into the LF-FDOCT and it enables three-dimensional OCT measurement with only one-dimensional mechanical scanning.