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81.
Midtrimester premature rupture of membranes (PROM) is an unusual complication of multiple gestation that most often results in poor obstetric outcome. Presented are four cases of twin pregnancy complicated by preterm PROM and umbilical cord prolapse at 16 to 21 weeks' gestation. After a period of expectant management, dilation and evacuation of only the presenting fetus was performed with careful ultrasound guidance, to attempt delayed interval delivery. This resulted in pregnancy prolongation of 42 to 133 days for the remaining cotwins. Dilation and evacuation of a single demised fetus in twin pregnancy complicated by PROM and cord prolapse can be accomplished with favorable clinical outcome.  相似文献   
82.
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   
83.
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   
84.
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   
85.
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   
86.
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   
87.
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   
88.
Several inflammatory cytokines that promote inflammation and pathogenesis in asthma signal through the Janus kinase 1 (JAK1) pathway. This phase I, randomized, placebo‐controlled trial assessed the pharmacokinetics and safety of single and multiple ascending doses up to 15 mg twice daily for 14 days of a JAK1 inhibitor, GDC‐0214, in healthy volunteers (HVs; n = 66). Doses were administered with a dry powder, capsule‐based inhaler. An accompanying open‐label gamma scintigraphy study in HVs examined the lung deposition of a single dose of inhaled Technetium‐99m (99mTc)‐radiolabeled GDC‐0214. GDC‐0214 plasma concentrations were linear and approximately dose‐proportional after both single and multiple doses. Peak plasma concentrations occurred at 15–30 min after dosing. The mean apparent elimination half‐life ranged from 32 to 56 h across all single and multiple dose cohorts. After single and multiple doses, all adverse events were mild or moderate, and none led to treatment withdrawal. There was no clear evidence of systemic toxicity due to JAK1 inhibition, and systemic exposure was low, with plasma concentrations at least 15‐fold less than the plasma protein binding‐corrected IC50 of JAK1 at the highest dose. Scintigraphy showed that approximately 50% of the emitted dose of radiolabeled GDC‐0214 was deposited in the lungs and was distributed well to the peripheral airways. 99mTc‐radiolabeled GDC‐0214 (1 mg) exhibited a mean plasma Cmax similar to that observed in phase I at the same dose level. Overall, inhaled GDC‐0214 exhibited pharmacokinetic properties favorable for inhaled administration.

Study Highlights
  • WHAT IS THE CURRENT KNOWLEDGE ON THE TOPIC?
Many factors drive asthma pathogenesis, including several cytokines that signal through the Janus kinase 1 (JAK1) pathway. Inhibition of JAK1 is a possible target for asthma treatments, but previous studies show oral JAK1 inhibitors lead to increased risk of severe infections, malignancy and cardiovascular events.
  • WHAT QUESTION DID THIS STUDY ADDRESS?
This study investigated the safety, pharmacokinetics, and lung deposition of GDC‐0214, an inhaled JAK1 inhibitor designed to target the lungs.
  • WHAT DOES THIS STUDY ADD TO OUR KNOWLEDGE?
Inhaled delivery of a JAK inhibitor for 14 days exhibited low systemic exposure, leading to few adverse events and limited systemic toxicity, while demonstrating high deposition in the lungs.
  • HOW MIGHT THIS CHANGE CLINICAL PHARMACOLOGY OR TRANSLATIONAL SCIENCE?
Local pulmonary application of JAK inhibitors may be an effective treatment for asthma with limited systemic risks.  相似文献   
89.
BackgroundThis study aimed to examine the prognostic significance of sarcopenia combined with systemic inflammation in patients who underwent curative hepatectomy for hepatocellular carcinoma (HCC).MethodsBetween January 2010 and July 2019, we identified 159 patients with HCC who underwent curative hepatectomy at three institutional centers. We retrospectively analyzed clinicopathological outcomes, surgical outcomes, platelet lymphocyte ratio (PLR) as a systemic inflammatory marker, and computed tomography (CT)-assessed sarcopenia at the third lumbar vertebra level (L3).ResultsSarcopenia was noted in 74 (46.5%) of 159 patients and was significantly associated with male sex, low body mass index (BMI), and high PLR. In the multivariate analysis, sarcopenia [hazard ratio (HR): 2.127, P=0.026] and high PLR (HR: 1.971, P=0.038) were associated with a decrease in overall survival (OS) but not in recurrence-free survival (RFS). The combination of sarcopenia and PLR status stratified the 5-year OS into 82.0% (non-sarcopenia and a low PLR), 68.3% (sarcopenia or a high PLR), and 44.4% (sarcopenia and a high PLR) (P=0.001). In the multivariate analysis, “sarcopenia and a high PLR” and “sarcopenia or a high PLR” were revealed to be significant predictors of OS (HR: 4.300, P=0.001 and HR: 2.723, P=0.010, respectively).ConclusionsSarcopenia and high PLR were significantly associated with poor OS. The combination of these two factors may be useful for predicting survival of patients with HCC undergoing curative hepatectomy.  相似文献   
90.
Type 1 diabetes (T1D) is caused by dysregulation of the immune system in the pancreatic islets, which eventually leads to insulin-producing pancreatic β-cell death and destabilization of glucose homeostasis. One of the major characteristics of T1D pathogenesis is the production of inflammatory mediators by macrophages that result in destruction or damage of pancreatic β-cells. In this study the inflammatory microenvironment of T1D was simulated with RAW264.7 cells and MIN6 cells, acting as macrophages and pancreatic β-cells respectably. In this setting, peroxiredoxin-1, an anti-oxidant enzyme was knocked down to observe its functions in the pathogenesis of T1D. RAW264.7 cells were primed with lipopolysaccharide and co-cultured with MIN6 cells while PRX-1 was knocked down in one or both cell types. Our results suggest that hindrance of PRX-1 activity or the deficiency of this enzyme in inflammatory conditions negatively affects pancreatic β-cell survival. The observed decrease in viability of MIN6 cells seems to be caused by nitric oxide production. Additionally, it seems that PRX-1 affects previously reported protective activity of IL-6 in pancreatic β cells as well. These results signify new, undiscovered roles for PRX-1 in inflammatory conditions and may contribute toward our understanding of autoimmunity.  相似文献   
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