Nutrition therapy in esophageal cancer-Consensus statement of the Gastroenterological Society of Taiwan.

A number of clinical guidelines on nutrition therapy in cancer patients have been published by national and international societies; however, most of the reviewed data focused on gastrointestinal cancer or non-cancerous abdominal surgery. To collate the corresponding data for esophageal cancer (EC), a consensus panel was convened to aid specialists from different disciplines, who are involved in the clinical nutrition care of EC patients. The literature was searched using MEDLINE, Embase, the Cochrane Central Register of Controlled Trials, and the ISI Web of Knowledge. We searched for the best evidence pertaining to nutrition therapy in the case of EC. The panel summarized the findings in 3 sections of this consensus statement, based on which, after the diagnosis of EC, an initial distinction is made between the patients, as follows: (1) Assessment; (2) Therapy in patients with resectable disease; patients receiving chemotherapy or chemoradiotherapy prior to resection, and patients with unresectable disease, requiring chemoradiotherapy or palliative therapy; and (3) Formula. The resulting consensus statement reflects the opinions of a multidisciplinary group of experts, and a review of the current literature, and outlines the essential aspects of nutrition therapy in the case of EC. The statements are: Patients with EC are among one of the highest risk to have malnutrition. Patient generated suggestive global assessment is correlated with performance status and prognosis. Nutrition assessment for patients with EC at the diagnosis, prior to definitive therapy and change of treatment strategy are suggested and the timing interval can be two weeks during the treatment period, and one month while the patient is stable. Patients identified as high risk of malnutrition should be considered for preoperative nutritional support (tube feeding) for at least 7-10 days. Various routes for tube feedings are available after esophagectomy with similar nutrition support benefits. Limited intrathoracic anastomotic leakage postesophagectomy can be managed with intravenous antibiotics and self-expanding metal stent (SEMS) or jejunal tube. Enteral nutrition in patients receiving preoperative chemotherapy or chemoradiation provides benefits of maintaining weight, decreasing toxicity, and preventing treatment interruption. Tube feeding or SEMS can offer nutrition support in patients with unresectable esophageal cancer, but SEMS is not recommended for those with neoadjuvant chemoradiation before surgery. Enteral immunonutrition may preserve lean body mass and attenuates stress response after esophagectomy. Administration of glutamine may decrease the severity of chemotherapy induced mucositis. Enteral immunonutrition achieves greater nutrition status or maintains immune functions during concurrent chemoradiation.

A randomised trial comparing real-time double-lumen endobronchial tube placement with the Disposcope® with conventional blind placement.

Double-lumen endobronchial tube placement is challenging. This study compared double-lumen tube placement with the Disposcope® , a wireless videostylet allowing real-time visualisation, with conventional blind placement. Patients undergoing elective thoracic surgery with normal airways requiring one-lung ventilation were randomly allocated into two groups (27 patients in each group). The Disposcope was used to assist left-sided double-lumen tube placement in one group, and conventional blind placement was performed in the control group. Placement in both groups was checked with fibreoptic bronchoscopy. The Disposcope-assisted group had a shorter total mean (SD) placement time (18.6 (2.5) s vs. 21.4 (2.9) s, p < 0.001), laryngoscopy to end of auscultation time (83.4 (3.0) s vs. 93.9 (5.7) s, p < 0.001) and total operation time (130.7 (6.1) s vs. 154.5 (6.3) s, p < 0.001). In the Disposcope-assisted group, the double-lumen tube was inserted in the correct side in all patients (100.0%), whereas in the conventional group, the double-lumen tube was placed in the correct side in 25 (92.6%) patients and in the wrong side in 2 (7.4%) patients; the difference was not significant (p = 0.150). In the Disposcope-assisted group, the double-lumen tube was inserted to the optimal depth in 24 (88.9%) patients, whereas in the conventional group it was inserted to the optimal depth in one (4.0%) patient. The Disposcope increased the success rate of double-lumen tube placement, and shortened the total operation time when compared with standard placement with confirmation using fibreoptic bronchoscopy, and may replace the conventional method.

Catheter-related right internal jugular vein thrombosis after chest surgery.

BACKGROUND: Central venous catheters (CVCs) are frequently used for monitoring haemodynamic status and rapidly delivering fluid therapy during the peri- and postoperative periods. Indwelling CVCs are typically used 7-14 days postoperatively for additional monitoring and treatment, but patients may develop asymptomatic catheter-related thrombosis, leading to life-threatening pulmonary embolism and death. Early detection helps to avoid such complications. METHODS: This prospective observational study investigated the risk factors associated with catheter-related right internal jugular vein thrombosis in patients undergoing chest surgery. The study enrolled 24 patients who were scheduled to receive chest surgeries during which catheters were needed. To detect thrombus formation, Doppler ultrasound examinations from the thyroid cartilage level to the supraclavicular region were used after CVC placement and on each of the following days until the catheter was removed. RESULTS: No thrombosis was found in patients before surgery, but it appeared in 75% (18/24) after surgery. The risks of thrombosis increased with a longer duration of anaesthesia, greater amounts of bleeding, and use of postoperative ventilator support. CONCLUSIONS: Earlier catheter removal may reduce the risk of catheter-related thrombosis and avoid possibly fatal complications after catheter-related thrombosis.

Electro-optically spectrum narrowed, multiline intracavity optical parametric oscillators.

We report on the first building of an active spectral narrowing mechanism in a pulsed, multiline optical parametric oscillator (OPO) based on a novel aperiodically poled lithium niobate (APPLN) device constructed using the aperiodic optical superlattice technique. The APPLN device functions simultaneously in the system as a multi-channel optical parametric down converter (OPDC) and an electro-optic (EO) gain spectral filter working on the corresponding (multiple) signal bands. When the APPLN OPO was installed in a diode pumped Nd:YVO4 laser system, highly narrowed dual-wavelength signal lines (at 1540 and 1550 nm) were observed at the output of the system through EO control of the APPLN. Correspondingly, an enhancement of the power spectral density of the source by a factor of ~7.8 with respect to the system operated in passive mode was found.

Electro-optic spectral tuning in a fan-out double-prism domain periodically poled lithium niobate intracavity optical parametric oscillator.

We report on the design and experimental demonstration of an electro-optically tunable, pulsed intracavity optical parametric oscillator (IOPO) based on a unique fan-out double-prism domain periodically poled lithium niobate (DPD PPLN) in a diode-pumped Nd:YVO4 laser. The PPLN device combines the functionalities of fan-out and ramped duty-cycle domain structured nonlinear crystals, working simultaneously as a continuous grating-period quasi-phase-matched optical parametric downconverter and an electro-optic beam deflector/Q switch in the laser system. When driving the fan-out DPD PPLN with a voltage pulse train and varying the DC offset of the pulse train, a pulsed IOPO was realized with its signal and idler being electro-optically tunable over the 1880 and 2453 nm bands at spectral tuning rates of 13.5 (measured) and 25.8 (calculated) nm/(kV/mm), respectively.

Adiabatic light transfer in titanium diffused lithium niobate waveguides.

We report on the realization of adiabatic light transfer in lithium niobate (LiNbO3) waveguides. This peculiar adiabatic tunneling scheme was implemented in a three-waveguide coupling configuration with the intermediate waveguide being inclined with respect to the outer waveguides to facilitate the adiabatic passage process. We have investigated and determined the adiabatic conditions of the LiNbO3 device in terms of the structure configuration of the waveguide system and found optimal structure parameters by both simulation and experimental approaches. Broadband adiabatic couplings of bandwidth ~456 and 185 nm and peak coupling efficiencies of >0.96 have been obtained with a 2-cm long device for TE- and TM-polarized fundamental modes, respectively. Longer (5 cm) devices were also studied and found to be useful in increasing the adiabaticity of the device, especially for the TM-polarized mode.

Electro-optically spectrum tailorable intracavity optical parametric oscillator.

We report a unique, pulsed intracavity optical parametric oscillator (IOPO) whose output spectrum is electro-optically (EO) tailorable based on an aperiodically poled lithium niobate (APPLN) working simultaneously as an optical parametric gain medium and an active gain spectrum filter in the system. We have successfully obtained from the IOPO the emission of single to multiple narrow-line signal spectral peaks in a near-infrared (1531 nm) band simply by electro-optic control. The power spectral density of the EO tailored signal can be enhanced by up to 10 times over the original (nontailored) signal.

Palliative enteral feeding for patients with malignant esophageal obstruction: a retrospective study.

BACKGROUND: Malignant esophageal obstruction leads to dysphagia, deterioration in quality of life, and malnutrition. Traditional bedside nasogastric (NG) tube placement is very difficult under these circumstances. However, endoscopically assisted NG tube placement under fluoroscopic guidance could be an alternative option for establishing palliative enteral nutrition. This study aimed to compare the clinical outcomes of enteral tube feeding and esophageal stenting for patients with malignant esophageal obstruction and a short life expectancy. METHODS: Thirty-one patients were divided into 3 groups according to their treatment modality: NG tube (n = 12), esophageal stent group (n = 10), and supportive care with nil per os (NPO) (n = 9). Enteral nutrition, clinical outcomes, length of hospital stay, and median survival were evaluated. RESULTS: There were no significant baseline differences among the groups, except in age. The tube and stent groups had significantly higher enteral calorie intake (p = 0.01), higher serum albumin (p < 0.01), shorter hospital stay (p = 0.01), and longer median survival (p < 0.01) than the NPO group. The incidence of dislodgement in the tube group was significantly higher than in the stent group (58% vs. 20%, respectively; p = 0.01). However, stenting costs more than NG tube placement. CONCLUSIONS: Palliative enteral feeding by NG tube is safe, inexpensive, and has a low complication rate. Endoscopically assisted NG tube placement under fluoroscopic guidance could be a feasible palliative option for malignant esophageal obstruction for patients who have a short life expectancy.

Two-dimensional aperiodic nonlinear photonic crystal in a dual-wavelength Nd:YVO4 laser for pulsed orange generation.

We report the design and construction of a highly integrated two-dimensional (2D) aperiodic nonlinear photonic crystal (NPC) for working in a diode-pumped, dual-wavelength (1064 and 1342 nm) Nd:YVO4 laser to demonstrate a compact, high-peak-power intracavity sum-frequency generator (ISFG) radiating at orange 593.5 nm. The 2D aperiodic NPC was built in quasi-phase-matched LiNbO3whose crystal domain was structured based on the aperiodic optical superlattice technique to best achieve its simultaneous performance of a dual-wavelength electro-optic Bragg Q-switch and a SFG in the Nd:YVO4 laser. When the NPC device was driven with a 350-V Q-switching voltage and a 1-kHz switching rate, we measured pulse energy of ~4.3 µJ (or peak power of ~531 W) at orange 593.5 nm from the constructed ISFG with 5.28-W diode power.

Characterization and analysis of finite-beam Bragg diffraction in a periodically poled lithium niobate electro-optic grating.

We report the study, both theoretical and experimental, of the finite-beam Bragg diffraction behavior of an electro-optic (EO) volume grating made of a periodically poled lithium niobate (PPLN) crystal. When a Gaussian laser beam is used, the experimental observations show that the diffraction characteristics of the PPLN EO Bragg device, including the diffraction mode pattern and diffraction efficiency, are closely related to the interaction beam size and applied voltage, which cannot be modeled properly by a simplified theory using the plane-wave approximation. In this work, we have developed a theoretical model for describing the diffraction behavior of a PPLN EO Bragg device based on the coupled-wave theory with the aid of the plane-wave decomposition method. Specifically, we found that it is the angular distribution (or the dephasing bandwidth) of the plane wave elements decomposed from the incident Gaussian beam and grating strength that determine the Bragg coupling behavior of the device. We also identified some other electro-optically induced effects in the PPLN grating as an important mechanism in affecting the diffraction performance of the present device, especially at high working voltages.

Rapid molecular diagnosis of the Gilbert's syndrome-associated exon 1 mutation within the UGT1A1 gene.

Gilbert's syndrome is suspected in patients with unconjugated hyperbilirubinemia caused by decreased activity of the UDP-glucuronosyltransferase 1A1 (UGT1A1) gene in the absence of abnormal liver function and hemolysis. The major genetic variants underlying Gilbert's syndrome are TATA-box repeats of the promoter region and exon 1 G211A of the coding region, particularly in Asians. The efficacy of DNA melting curve analysis, however, has not been established for the G211A mutation. For rapid and accurate molecular diagnosis of Gilbert's syndrome, DNA melting curve analysis was evaluated for its genotyping capability not only for TATA-box repeats of the UGT1A1 promoter, but also for G211A of UGT1A1 exon 1. TA repeats within the TATA-box sequence and the exon 1 G211A mutation of the UGT1A1 gene were analyzed by DNA melting curve analysis. To evaluate the assay reliability, direct sequencing or polyacrylamide gel electrophoresis was used as a comparative method. All homozygous and heterozygous polymorphisms of A(TA)7TAA within the TATA-box allele and of exon 1 G211A mutants of the UGT1A1 gene were successfully identified with DNA melting curve analysis. DNA melting curve analysis is, therefore, an effective molecular method for the rapid diagnosis of Gilbert's syndrome, as it detects not only TATA-box polymorphisms but also the exon 1 G211A mutation located within the UGT1A1 gene.

Tunable, pulsed multiline intracavity optical parametric oscillator using two-dimensional MgO: periodically poled lithium niobate-aperiodically poled lithium niobate.

We report a tunable, pulsed multiline intracavity optical parametric oscillator (IOPO) realized in an Nd:YVO4 laser using a two-dimensionally domain engineered MgO:LiNbO3 as simultaneously an electro-optic Bragg Q switch and a multichannel optical parametric downconverter. The MgO:LiNbO3 was periodically and aperiodically poled along the crystallographic y and x axes, respectively, to simultaneously satisfy the phase-matching conditions required by the two quasi-phase-matching devices. When Q switched by 1 kHz, 300 V pulses, three signal lines at 1518, 1526, and 1534 nm were simultaneously generated, each with a peak power of ∼1 kW from the IOPO at 8.3 W diode power at 50°C. Spectral tuning of the three-line IOPO with temperature was demonstrated.

Double-prism domain PPLN for simultaneous laser Q-switching and optical parametric oscillation in a Nd:YVO4 laser.

We report a design and demonstration of an electro-optically Q-switched intracavity optical parametric oscillator (IOPO) based on a unique ramped duty-cycle periodically poled lithium niobate (PPLN) in a diode-pumped 1064-nm Nd:YVO(4) laser. The PPLN crystal, having a double-prism domain (DPD) structure with a domain period of 30 µm, can work simultaneously as an electro-optic (EO) beam deflector (and therefore an EO Q-switch in the laser cavity) and an optical parametric down converter. The characterized deflection sensitivity of the DPD PPLN device was 1.15°/kV-cm. At a 180-V Q-switching voltage and a 1-kHz switching rate, we measured a down-converted signal at 1550 nm with pulse energy of >8.1 µJ (or peak power of >2.3 kW) from the constructed IOPO at 7.5-W diode pump power. Continuous wavelength tuning of the IOPO signal was also demonstrated.

Electro-optically tunable, multi-wavelength optical parametric generators in aperiodically poled lithium niobates.

We report on the design and demonstration of electro-optically tunable, multi-wavelength optical parametric generators (OPGs) based on aperiodically poled lithium niobate (APPLN) crystals. Two methods have been proposed to significantly enhance the electro-optic (EO) tunability of an APPLN OPG constructed by the aperiodic optical superlattice (AOS) technique. This is done by engineering the APPLN domain structure either in the crystal fabrication or in the crystal design process to increase the length or block-number difference of the two opposite-polarity domains used in the structure. Several orders of magnitude enhancement on the EO tuning rate of the APPLN OPGs constructed by the proposed techniques for simultaneous multiple signal wavelength generation over a conventional one has been demonstrated in a near infrared band (1500-1600 nm).

Internal Q-switching and self-optical parametric oscillation in a two-dimensional periodically poled Nd:MgO:LiNbO3 laser.

We report on an internally Q-switched self-optical parametric oscillator (SOPO) based on a monolithic two-dimensional (2D) periodically poled Nd:MgO:LiNbO(3) (Nd:MgO:PPLN) integrating three device functionalities of a laser gain medium, an electro-optic Bragg Q-switch, and an optical parametric gain medium (OPGM). The quasi-phase-matching conditions required by the Bragg Q-switch and OPGM are both satisfied in the 2D nonlinear photonic crystal (NPC) structure formed in the Nd:MgO:PPLN. A 1525 nm signal with a pulse energy of ∼3.3 µJ (>350 W peak power) was obtained from the SOPO at 8.5 W diode pump power. An off-angle signal at 1612 nm, amplified by a unique gain-enhancement effect in this 2D NPC, was also observed. Tuning of the SOPO in the eye-safe region was demonstrated.

Protein Profile in Corpus Luteum during Pregnancy in Korean Native Cows.

Steroidogenesis requires coordination of the anabolic and catabolic pathways of lipid metabolism, but the profile of proteins associated with progesterone synthesis in cyclic and pregnant corpus luteum (CL) is not well-known in cattle. In Experiment 1, plasma progesterone level was monitored in cyclic cows (n = 5) and pregnant cows (n = 6; until d-90). A significant decline in the plasma progesterone level occurred at d-19 of cyclic cows. Progesterone level in abbatoir-derived luteal tissues was also determined at d 1 to 5, 6 to 13 and 14 to 20 of cyclic cows, and d-60 and -90 of pregnant cows (n = 5 each). Progesterone level in d-60 CL was not different from those in d 6 to 13 CL and d-90 CL, although the difference between d 6 to 13 and d-90 was significant. In Experiment 2, protein expression pattern in CL at d-90 (n = 4) was compared with that in CL of cyclic cows at d 6 to 13 (n = 5). Significant changes in the level of protein expression were detected in 32 protein spots by two-dimensional polyacrylamide gel electrophoresis (2-DE), and 23 of them were identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). Six proteins were found only in pregnant CL, while the other 17 proteins were found only in cyclic CL. Among the above 6 proteins, vimentin which is involved in the regulation of post-implantation development was included. Thus, the protein expression pattern in CL was disorientated from cyclic luteal phase to mid pregnancy, and alterations in specific CL protein expression may contribute to the maintenance of pregnancy in Korean native cows.