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101.
OBJECTIVE: To compare the efficacy, results and complications of using the pulsed bipolar system (PlasmaKinetic; Gyrus Medical, Maple Grove, MN) and conventional bipolar electrosurgery (Kleppinger bipolar forceps; Richard Wolf Instruments, Vernon Hills, IL) in laparoscopic radical hysterectomy and pelvic lymphadenectomy in the management of early invasive cervical carcinoma. METHODS: This was a retrospective case-control study. We recruited consecutively 38 patients with cervical cancer for laparoscopic radical hysterectomy with pulsed bipolar system. For comparison, we recruited consecutively the latest 38 patients with cervical cancer for laparoscopic radical hysterectomy with conventional bipolar electrosurgery in the same period. From Jan. 2001 to Dec. 2005, total 76 patients with cervical cancer for laparoscopic radical hysterectomy were recruited for statistical analysis. RESULTS: No significant difference was found between the two groups in terms of age, body weight, staging, and hospital stay. There were statistically significant difference in blood loss and operative time. The blood loss was more in conventional bipolar electrosurgery group (mean 564 ml, median 500 ml, range 50-2400 ml) compared with pulsed bipolar system group (mean 397 ml, median 350 ml, range 100-1200 ml) (p<0.03). But there was no statistically significant difference in blood transfusion between the two groups (p=0.454). The operation time for the conventional bipolar electrosurgery group (mean 229 min, median 232 min, range 121-352 min) was longer than that for the pulsed bipolar system group (mean 172 min, median 177 min, range 65-267 min) (p<0.001). None of the laparoscopic procedure was required to be converted to laparotomy. There was no significant difference in the intra-operative complication, but there was statistically less postoperative complication in the pulsed bipolar system group (p<0.01). There was no significant difference in recurrence rate in both groups. CONCLUSIONS: Our findings indicate that pulsed bipolar system is more effective in laparoscopic radical hysterectomy when compared with conventional bipolar electrosurgery. Pulsed bipolar system has advantage over conventional bipolar electrosurgery in less blood loss, shorter operative time, less postoperative complication and may offer an alternative option for patients undergoing laparoscopic radical hysterectomy. 相似文献
102.
We aimed to investigate association between parental age and the risks of term low birth weight and macrosomia.This was a retrospective cohort study using a national database including 2,245,785 term singleton live births with complete parental age data. Old parental age was defined as 35 years or older. Odd ratios (OR) for term low birth weight and macrosomia were analyzed using univariate and multivariate logistic regression analysis.Neonatal sex, maternal occupation, parity, nationality, age, and paternal age were significant factors of term low birth weight and macrosomia, in univariate analysis. In multivariate analysis, old maternal age (≥35 years old) showed increased odds of term low birth weight and macrosomia (aOR = 1.122, 95% CI: 1.083 –1.162; and aOR = 1.166, 95% CI: 1.143 – 1.189, respectively). Similarly, old paternal age (≥35 years old) showed increased odds of term low birth weight and macrosomia (aOR = 1.090, 95% CI: 1.058 –1.122; and aOR = 1.101, 95% CI: 1.083 – 1.119, respectively). Maternal education that lasted more than 12 years had reduced odds of term low birth weight and macrosomia (OR = 0.817, 95% CI: 0.792 –0.842; and OR = 0.894, 95% CI: 0.879 – 0.91, respectively). Paternal education that lasted more than 12 years also had reduced odds of term low birth weight and macrosomia (OR = 0.865, 95% CI: 0.84 –0.892; and OR = 0.897, 95% CI: 0.881 – 0.913, respectively).This study suggests that not only maternal age but also paternal age are significantly associated with term low birth weight and macrosomia. In addition, parental education levels are also associated with term low birth weight and macrosomia. 相似文献
103.
In the past few decades, scientists have actively worked on developing effective drug delivery systems (DDSs) as means to control life-threatening diseases and challenging illnesses. In order to develop such DDSs, nanobiotechnological strategies have been introduced, and many nanomaterial-based DDS platforms have been proposed. Among these nanomaterials, DDSs based on exosomes and hybrids of exosomes have been focused upon and developed due to their low toxicity, high bioactivity, and biocompatibility. In this review, we describe the processes involved in drug loading into exosomes and the surface modification of exosomes with treatment agents. Furthermore, we describe the synthesis methods of hybrid exosomes with organic or inorganic nanoparticles. Moreover, we focus on the effective therapeutic applications of exosome-based DDSs against various diseases. In conclusion, we show that exosomes and hybrids of exosomes show excellent drug carrier potential and capacity.In the past few decades, scientists have actively worked on developing effective drug delivery systems (DDSs) as means to control life-threatening diseases and challenging illnesses. 相似文献
104.
Taehyeok Hwang Hyo Jung Lee Woo Sung Park Dong-Min Kang Mi-Jeong Ahn Hyonok Yoon Jae Cheal Yoo Dong Kyu Moon Dong Kyun Woo 《International journal of medical sciences》2022,19(7):1131
Although melanogenesis is a defense mechanism against ultraviolet (UV)-induced skin damage, abnormally excessive melanin production causes pigmentation disorders. Tyrosinase, as a key factor for melanin synthesis, plays an important role in inducing skin pigmentation. Therefore, the inhibition of tyrosinase is crucial in preventing skin pigmentation in the cosmetics and medicine fields. However, the majority of well-known tyrosinase inhibitors have been discontinued due to toxic effects on the skin or lack of selectivity and/or stability. In this study, we evaluated possible anti-melanogenic effects of catechin-7-O-α-L-rhamnopyranoside (C7R) isolated from the stem bark of Ulmus parvifolia, to discover a new tyrosinase inhibitor that has both safety and stability. When C7R was pretreated in B16F10 melanoma cells stimulated by α-melanocyte-stimulating hormone, this compound reduced melanin accumulation and murine tyrosinase activity. In line with these results, C7R inhibits tyrosinase purified from a mushroom in vitro like kojic acid and arbutin. Furthermore, C7R exhibited a competitive inhibition on a Lineweaver-Burk plot. Next, the underlying mechanisms of the C7R-mediated tyrosinase inhibitory effect were sought through docking simulation and pharmacophore analysis between tyrosinase residues and C7R. The results of these analyses showed that C7R had binding energy of -14.5kcal/mol, and indicated that C7R interacts with tyrosinase through an aromatic ring and various hydrophobic and hydrogen bonds. Together, our results suggest that C7R can be applied as a novel natural anti-melanogenic agent that inhibits tyrosinase. 相似文献
105.
Kookjin Heo Young-Woong Song Dahee Hwang Min-Young Kim Jang-Yeon Hwang Jaekook Kim Jinsub Lim 《RSC advances》2022,12(22):14209
In this article, we report the effect of a Li6.75La3Zr2Al0.25O12 (LLZAO) composite Li(Ni0.8Co0.1Mn0.1)O2 (NCM811) cathode material on the performance of all-solid-state batteries (ASSBs) with oxide-based organic/inorganic hybrid solid electrolytes. The layered structure of Ni-rich cathode material Li(NixCo(1−x)/2Mn(1−x)/2)O2 (x > 0.6) (NCM) exhibiting a high specific capacity is among the suitable cathode materials for next-generation energy storage systems, particularly electric vehicles and portable devices for all-solid-state batteries. However, the ASSBs present a problem—the resistance at the interface between a cathode and solid electrolyte is larger than that with a liquid electrolyte because of point contact. To solve this problem, using a simultaneous co-precipitation method, we composited various amounts of LLZAO material and an ion conducting material on the cathode material''s surface. Therefore, to optimize the value of the LLZAO material in the composite cathode material, the structure, cycling stability, and rate performance of the NCM–LLZAO composite cathode material in ASSBs with oxide-based inorganic/organic-hybrid electrolytes were investigated using powder X-ray diffraction analysis, field-emission scanning electron microscopy, electrochemical impedance spectroscopy, and galvanostatic measurements. A composite cathode material contributes to the improvement of interfacial resistance between cathode material and solid electrolyte in the all-solid-state batteries. 相似文献
106.
Sung Hoon Choi Chang Moo Kang Jee Ye Kim Ho Kyoung Hwang Woo Jung Lee 《Surgical endoscopy》2013,27(4):1412-1413
Background
Spleen-preserving distal pancreatectomy can be performed safely and effectively by resecting both splenic vessels (Warshaw procedure) [1–4]. This simplified spleen-preserving technique might also be applied to minimally invasive distal pancreatectomy of benign and borderline malignant tumor [5, 6].Methods
Although the conservation of both splenic vessels is paramount to preserving the spleen during laparoscopic distal pancreatectomy, preservation of the splenic vessels is not always possible, especially under the following conditions: (1) relatively large tumor, (2) associated with chronic pancreatitis, (3) tumor abutting splenic vascular structures, and (4) bleeding during the splenic vessel conserving procedure, which are potential indications of laparoscopic extended Warshaw procedure. Patient preparation and position was the same as that described in our previous study [7].Results
During the study’s time period, 38 consecutive patients underwent laparoscopic spleen-preserving distal pancreatectomy. Of those, five patients underwent a laparoscopic extended Warshaw procedure, which all included among 16 patients of extended distal pancreatectomy by dividing the pancreas at the pancreatic neck. All patients were women with a median age of 55 (range, 38–75) years. Median total operation time and blood loss were 215 (range, 200–386) minutes and 100 (range, 0–300) ml, respectively. The median length of hospital stay was 8 (range, 5–15) days. All of postoperative complications (two grade A and two grade B postoperative pancreatic fistula; one grade A bleeding) were able to be treated conservatively. During the median follow-up period of 11 (range, 7–42) months, one focal splenic infarction and one gastric varix were noted; however, no clinically significant complications were reported.Conclusions
Laparoscopic spleen-preserving extended distal pancreatectomy with resection of both the splenic vessels is feasible and safe [8]. This surgical technique is thought to increase the chance of preservation of the spleen with minimally invasive distal pancreatectomy in well-selected benign or borderline malignant tumor of the distal pancreas. 相似文献107.
Daegwang Yoo Shin Hwang Ki-Hun Kim Chul-Soo Ahn Deog-Bok Moon Tae-Yong Ha Dong-Hwan Jung Gil-Chun Park Bo-Hyun Jung Sung-Hwa Kang Sung-Gyu Lee 《Journal of gastrointestinal surgery》2014,18(9):1604-1609
Background
Atrophy of the pancreatic parenchyma, which occurs frequently after pylorus-preserving pancreaticoduodenectomy (PPPD), is often associated with pancreatic exocrine insufficiency. Many surgeons prefer to insert a drainage tube into the remnant pancreatic duct primarily to prevent pancreatic leakage at the pancreaticojejunostomy (PJ) after PPPD. Drainage methods vary widely but can be roughly classified as internal or external drainage. This study intended to evaluate their effects on pancreatic parenchymal atrophy following PPPD.Methods
Fifty-seven patients who underwent PPPD were retrospectively divided into two groups, 28 who underwent external and 29 who underwent internal pancreatic drainage. External drainage tubes were removed 4 weeks after PPPD. The volume of the pancreatic parenchyma was serially measured on abdominal computed tomography (CT) scans before PPPD, as well as 7 days and 3, 6, and 12 months after surgery. Degree of pancreatic parenchymal atrophy was determined by calculating pancreatic volume relative to that on day 7.Results
Univariate analysis showed that patient sex, age, body mass index, concurrent pancreatitis, pathology, and types of PJ did not significantly affect changes in pancreatic volume following PPPD. The degree of pancreatic volume atrophy did not differ significantly in the external and internal drainage groups. No patient in the external drainage group experienced drainage-related surgical complications. The incidence of PJ leak was comparable in the two groups. Postoperative pancreatic atrophy did not induce new-onset diabetes mellitus at 1 year.Conclusions
Both external and internal pancreatic drainage methods showed similar atrophy rate of the pancreatic parenchyma following PPPD. 相似文献108.
Background
Increased nuclear factor κB (NF-κB) bioexpression, as well as TNF-α, IL-1β and IL-6 levels, were observed after aneurysmal subarachnoid hemorrhage (SAH). It is of interest to investigate the effect of 6-mercaptopurine (6-mp) on cytokines/NF-κB in this SAH model.Materials and methods
A rodent double-hemorrhage SAH model was employed. Serum and cerebrospinal fluid (CSF) samples were collected to examine IL-1, IL-6 and TNF-α levels. NF-κB subunit p65 and its inhibitor of nuclear factor κB (IκB) were examined (by Western blot). TNF-α was used to induce the phosphorylation of IκB in the presence or absence of 6-mp.Results
Nuclear NF-κB subunit p65/IκB kinase in the basilar artery was over-expressed, and cytokines was notably increased in the SAH groups, compared with the controls (P?0.01). In the 6-mp SAH group, obvious reduction was observed in NF-κB subunit p65 (nuclei) (P?0.01). Treatment with 6-mp significantly reduced IL-1β and TNF-α levels to those of the healthy control. 6-Mercaptopurine also significantly increased the level of IκB in the TNF-α-stimulated SAH rats.Conclusions
Through inhibiting IκB bioexpression, 6-mp decreases NF-κB-related IL-1β, IL-6, and TNF-α in the presence of SAH. The study suggests 6-mp exerts vascular anti-inflammatory properties through inhibiting IκB kinase and subsequently blocks bio-activation of NF-κB and related cytokines, which may contribute to its antivasospastic effect in animals subjected to SAH. 相似文献109.
Background
We evaluated vascular patency and potential changes in preserved spleens after laparoscopic spleen-preserving distal pancreatectomy (SPDP) with conservation of both splenic vessels.Methods
We retrospectively analyzed the patency of conserved splenic vessels in patients who underwent laparoscopic or robotic splenic vessel-conserving SPDP from January 2006 to August 2010. The patency of the conserved splenic vessels was evaluated by abdominal computed tomography and classified into three grades according to the degree of severity.Results
Among 30 patients with splenic vessel-conserving laparoscopic SPDP, 29 patients with complete follow-up data were included in this study. During the follow-up period (median: 13.2?months), grades 1 and 2 splenic arterial obliteration were observed in one patient each. A total of five patients (17.2%) showed grade 1 or 2 obliteration in conserved splenic veins. Most patients (82.8%) had patent conserved splenic vein. Four patients (13.8%) eventually developed collateral venous vessels around gastric fundus and reserved spleen, but no spleen infarction was found, and none presented clinical relevant symptoms, such as variceal bleeding. There was no statistical difference in vascular patency between the laparoscopic and robotic groups (P?>?0.05).Conclusions
Most patients showed intact vascular patency in conserved splenic vessels and no secondary changes in the preserved spleen after laparoscopic splenic vessel-conserving SPDP. 相似文献110.
Jin Wook Lee Hyo Jeong Lee Dae Sung Kim Jiyoung Yoon Seung Wook Hong Ha Won Hwang Jong-Soo Lee Gwang-Un Kim Sinwon Lee Jaewon Choe Jin Hwa Park Dong-Hoon Yang Jeong-Sik Byeon 《Gut and liver》2022,16(3):404
Background/AimsThe worldwide coronavirus disease 2019 pandemic has led endoscopists to use personal protective equipment (PPE) for infection prevention. This study aimed to investigate whether wearing a face shield as PPE affects the quality of colonoscopy.MethodsWe reviewed the medical records and colonoscopy findings of patients who underwent colonoscopies at Asan Medical Center, Korea from March 10 to May 31, 2020. The colonoscopies in this study were performed by five gastroenterology fellows and four expert endoscopists. We compared colonoscopy quality indicators, such as withdrawal time, adenoma detection rate (ADR), mean number of adenomas per colonoscopy (APC), polypectomy time, and polypectomy adverse events, both before and after face shields were added as PPE on April 13, 2020.ResultsOf the 1,344 colonoscopies analyzed, 715 and 629 were performed before and after the introduction of face shields, respectively. The median withdrawal time was similar between the face shield and no-face shield groups (8.72 minutes vs 8.68 minutes, p=0.816), as was the ADR (41.5% vs 39.8%, p=0.605) and APC (0.72 vs 0.77, p=0.510). Polypectomy-associated quality indicators, such as polypectomy time and polypectomy adverse events were also not different between the groups. Quality indicators were not different between the face shield and no-face shield groups of gastroenterology fellows, or of expert endoscopists.ConclusionsColonoscopy performance was not unfavorably affected by the use of a face shield. PPE, including face shields, can be recommended without a concern about colonoscopy quality deterioration. 相似文献