336 research outputs found
A Novel Surgical Technique: Single-Incision Transumbilical Laparoscopic Roux-en-Y Gastric Bypass
Conventional laparoscopic Roux-en-Y gastric bypass (LRYGB) is a gold standard for bariatric surgery, but the procedure requires five to seven incisions for placement of multiple trocars and thus may produce less-than-ideal cosmetic results. We have developed a new approach, single-incision transumbilical LRYGB (SITU-LRYGB) to treat morbid obesity. We compared the surgical results and patient satisfaction in a study of five-port LRYGB and SITU-LRYGB. Fifty morbidly obese patients (14 males, 36 females) underwent either Roux-en-Y gastric bypass with five-port LRYGB or the SITU-LRYGB approach. During the operation, we used a novel intraoperative liver traction method with a “liver suspension tape” that we specifically designed for SITU-LRYGB. Compared to five-port surgery with SITU-LRYGB, there were no intraoperative complications, wound healing was excellent, and there was no abdominal scarring. SITU surgical time was longer than that with five-port LRYGB (99.8 vs. 67.6 min, P < 0.001). Patients treated with the five-port method were more obese than those in the SITU group (127.9 vs. 112.4 kg, P = 0.016). After the bariatric surgery, no difference in comorbidity was found in both groups. Patient satisfaction was greater with SITU than with the five-port method (4.48 vs. 3.96, P = 0.006). Roux-en-Y gastric bypass can be successfully achieved via a single umbilical incision, a method that provides a short operative time and good recovery and eliminates abdominal scarring
A water-immersible 2-axis scanning mirror microsystem for ultrasound and photoacoustic microscopic imaging applications
For both ultrasound and photoacoustic microscopic imaging, a fast scanning ability is required, whereas the liquid environment for acoustic propagation limits the usage of traditional MEMS scanning mirrors. In this paper, a new waterimmersible scanning mirror microsystem has been designed, fabricated and tested. To achieve reliable underwater scanning, flexible polymer torsion hinges fabricated by laser micromachining were used to support the reflective silicon mirror plate. Two efficient electromagnetic microactuators consisting of compact RF choke inductors and high-strength neodymium magnet disc were constructed to drive the silicon mirror plate around a fast axis and a slow axis, respectively. The performance of the water-immersible scanning mirror microsystem in both air and water were tested using the laser tracing method. For the fast axis, the resonance frequency reached 224 Hz in air and 164 Hz in water, respectively. The scanning angles in air and water under ±10 V AC driving (at the resonance frequencies) were ±13.6° and ±10°. The scanning angles in both air and water under ±16 V DC driving were ±12°. For the slow axis, the resonance frequency reached 55 Hz in air and 38 Hz in water, respectively. The scanning angles in air and water under ±10 V AC driving (at the resonance frequencies) were ±8.5° and ±6°. The scanning angles in both air and water under ±10 V DC driving were ± 6.5°. The feasibility of using such a water-immersible scanning mirror microsystem for scanning ultrasound microscopic (SAM) imaging has been demonstrated with a 25-MHz ultrasound pulse/echo system and a target consisting of three optical fibers
Real-time photoacoustic flow cytography and photothermolysis of single circulating melanoma cells in vivo
Metastasis is responsible for as many as 90% of cancer-related deaths, and the deadliest skin cancer, melanoma, has a high propensity for metastasis. Since hematogenous spread of circulating tumor cells (CTCs) is cancer’s main route of metastasis, detecting and destroying CTCs can impede metastasis and improve patients’ prognoses. Extensive studies employing exogenous agents to detect tumor-specific biomarkers and guide therapeutics to CTCs have achieved promising results, but biosafety remains a critical concern. Taking another approach, physical detection and destruction of CTCs is a safer way to evaluate and reduce metastasis risks. Melanoma cells strongly express melanosomes, providing a striking absorption contrast with the blood background in the red to near-infrared spectrum. Exploiting this intrinsic optical absorption contrast of circulating melanoma cells, we coupled dual-wavelength photoacoustic flow cytography with a nanosecond-pulsed laser killing mechanism that specifically targets melanoma CTCs. We have successfully achieved in vivo label-free imaging of rare single CTCs and CTC clusters in mice. Further, the photoacoustic signal from a CTC immediately hardware-triggers a lethal pinpoint laser irradiation that lyses it on the spot in a thermally confined manner. Our technology can facilitate early inhibition of metastasis by clearing circulating tumor cells from vasculature
Intraprostatic injection of botulinum toxin type- A relieves bladder outlet obstruction in human and induces prostate apoptosis in dogs
BACKGROUND: With the increasing interest with botulinum toxin – A (BTX-A) application in the lower urinary tract, we investigated the BTX-A effects on the canine prostate and also in men with bladder outlet obstruction (BOO) due to benign prostatic hyperplasia (BPH). METHODS: Transperineal injection into the prostate using transrectal ultrasound (TRUS) was performed throughout the study. Saline with or without 100 U of BTX-A was injected into mongrel dogs prostate. One or 3 months later, the prostate was harvested for morphologic and apoptotic study. In addition, eight BPH patients refractory to α-blockers were treated with ultrasound guided intraprostatic injection of 200 U of BTX-A. RESULTS: In the BTX-A treated dogs, atrophy and diffuse apoptosis was observed with H&E stain and TUNEL stain at 1 and 3 months. Clinically, the mean prostate volume, symptom score, and quality of life index were significantly reduced by 18.8%, 73.1%, and 61.5% respectively. Maximal flow rate significantly increased by 72.0%. CONCLUSION: Intraprostatic BTX-A injection induces prostate apotosis in dogs and relieves BOO in humans. It is therefore a promising alternative treatment for refractory BOO due to BPH
PALM: A Paralleled and Integrated Framework for Phylogenetic Inference with Automatic Likelihood Model Selectors
BACKGROUND: Selecting an appropriate substitution model and deriving a tree topology for a given sequence set are essential in phylogenetic analysis. However, such time consuming, computationally intensive tasks rely on knowledge of substitution model theories and related expertise to run through all possible combinations of several separate programs. To ensure a thorough and efficient analysis and avert tedious manipulations of various programs, this work presents an intuitive framework, the phylogenetic reconstruction with automatic likelihood model selectors (PALM), with convincing, updated algorithms and a best-fit model selection mechanism for seamless phylogenetic analysis. METHODOLOGY: As an integrated framework of ClustalW, PhyML, MODELTEST, ProtTest, and several in-house programs, PALM evaluates the fitness of 56 substitution models for nucleotide sequences and 112 substitution models for protein sequences with scores in various criteria. The input for PALM can be either sequences in FASTA format or a sequence alignment file in PHYLIP format. To accelerate the computing of maximum likelihood and bootstrapping, this work integrates MPICH2/PhyML, PalmMonitor and Palm job controller across several machines with multiple processors and adopts the task parallelism approach. Moreover, an intuitive and interactive web component, PalmTree, is developed for displaying and operating the output tree with options of tree rooting, branches swapping, viewing the branch length values, and viewing bootstrapping score, as well as removing nodes to restart analysis iteratively. SIGNIFICANCE: The workflow of PALM is straightforward and coherent. Via a succinct, user-friendly interface, researchers unfamiliar with phylogenetic analysis can easily use this server to submit sequences, retrieve the output, and re-submit a job based on a previous result if some sequences are to be deleted or added for phylogenetic reconstruction. PALM results in an inference of phylogenetic relationship not only by vanquishing the computation difficulty of ML methods but also providing statistic methods for model selection and bootstrapping. The proposed approach can reduce calculation time, which is particularly relevant when querying a large data set. PALM can be accessed online at http://palm.iis.sinica.edu.tw
Intramuscular electroporation with the pro-opiomelanocortin gene in rat adjuvant arthritis
Endogenous opioid peptides have an essential role in the intrinsic modulation and control of inflammatory pain, which could be therapeutically useful. In this study, we established a muscular electroporation method for the gene transfer of pro-opiomelanocortin (POMC) in vivo and investigated its effect on inflammatory pain in a rat model of rheumatoid arthritis. The gene encoding human POMC was inserted into a modified pCMV plasmid, and 0–200 μg of the plasmid-POMC DNA construct was transferred into the tibialis anterior muscle of rats treated with complete Freund's adjuvant (CFA) with or without POMC gene transfer by the electroporation method. The safety and efficiency of the gene transfer was assessed with the following parameters: thermal hyperalgesia, serum adrenocorticotropic hormone (ACTH) and endorphin levels, paw swelling and muscle endorphin levels at 1, 2 and 3 weeks after electroporation. Serum ACTH and endorphin levels of the group into which the gene encoding POMC had been transferred were increased to about 13–14-fold those of the normal control. These levels peaked 1 week after electroporation and significantly decreased 2 weeks after electroporation. Rats that had received the gene encoding POMC had less thermal hypersensitivity and paw swelling than the non-gene-transferred group at days 3, 5 and 7 after injection with CFA. Our promising results showed that transfer of the gene encoding POMC by electroporation is a new and effective method for its expression in vivo, and the analgesic effects of POMC cDNA with electroporation in a rat model of rheumatoid arthritis are reversed by naloxone
Investigation of vancomycin- resistant Enterococci (VRE) colonization in a intensive care of medical center in southern Taiwan
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