1,533 research outputs found
Fabrication of Modified MMT/Glass/Vinylester Multiscale Composites and Their Mechanical Properties
Montmorillonite (MMT) may become a preferred filler material for fiber-reinforced polymer (FRP) composites due to its high aspect ratio, large surface area, and low charge density. In the present paper, MMT/glass/vinylester multiscale composites are prepared with untreated and surface-treated MMT clay particles with an MMT content of 1.0 wt%. Effects of surface treatment on mechanical properties of MMT/glass/vinylester multiscale composites are investigated through tensile and bending tests, which revealed enhanced mechanical properties in the case of surface-treated MMT. Thermal properties are studied through thermogravimetric analysis (TGA) and dynamic mechanical analysis (DMA). X-Ray diffraction is performed to investigate the interaction between MMT and the matrix. Fourier Transform Infrared (FTIR) is also performed for both untreated and surface-treated MMT. Furthermore, Field Emission-Scanning Electron Microscope (FE-SEM) is conducted to investigate the path of fracture propagation within the composite surface, showing that the surface-treated MMT based multiscale composite has better interactions with the host matrix than the untreated MMT multiscale composites. These composites with enhanced mechanical strength can be used for various mechanical applications
Physiological responses of two halophytic grass species under drought stress environment
The physiological responses of two halophytic grass species, Halopyrum mucronatum (L.) Staph. and Cenchrus ciliaris (L.), under drought stress were evaluated. Biomass accumulation, relative water content, free proline, H2O2 content, stomatal conductance, photosynthetic performance and quantum yield (Fv/Fm ratio) were studied. Under drought conditions, these halophytic plants expressed differential responses to water defi cit. Stomatal conductance and free proline content were higher in H. mucronatum than in C. ciliaris, while H2O2 content in H. mucronatum was substantially lower than in C. ciliaris. Performance index showed considerable sensitivity to a water deficit condition, more so in C. ciliaris than in H. mucronatum. Results were discussed in relation to comparative physiological performance and antioxidant enzymes activity of both halophytic grasses under drought stress
Increased pulsatility index of the basilar artery is a risk factor for neurological deterioration after stroke: a case control study
Background : Higher pulsatility of the middle cerebral artery (MCA) is known to be associated with stroke progression. We investigated whether pulsatility index (PI) of the basilar artery (BA) can predict neurological deterioration (ND) after acute cerebral infarction.
Methods : A total of 708 consecutive patients with acute ischemic stroke who had undergone transcranial Doppler (TCD) ultrasonography were included. ND was defined as an increase in the National Institutes of Health Stroke Scale scores by two or more points after admission. The patients were categorized into quartiles according to BA PI. Multivariable logistic regression analysis was performed to examine whether BA PI is independently associated with ND.
Results : BA PI was well correlated with the right (n = 474, r2 = 0.573, P < 0.001) by Pearson correlation analysis although MCA PI could not be measured from right MCA (n = 234, 33.05%) and left MCA (n = 252, 35.59%) by TCD owing to insufficient temporal bone window. Multivariable logistic regression analysis including age, sex, cerebral atherosclerosis burden, National Institutes of Health Stroke Scale at admission, and the proportion of patients with current smoking status, hypertension, diabetes mellitus, atrial fibrillation revealed that the higher BA PI (odds ratio, 3.28; confidence interval, 1.07–10.17; P = 0.038) was independently associated with ND.
Conclusions : BA PI, which would be identified regardless of temporal window, could predict ND among acute stroke patients.The work was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (NRF-2017R1D1A1B03029909, NRF-2019R1F1A1059455) and by the Korean Society of Hypertension (2019). The funding has no role in design, collection, analysis, or interpretation of data; in the writing of the manuscript; and in the decision to submit the manuscript for publication
A Survey on Ubiquitous Healthcare Service Demand among Diabetic Patients
BackgroundAdvanced information technology can be used when developing diagnostic and treatment strategies to provide better care for diabetic patients. However, the levels of need and demand for the use of technological advances have not been investigated in diabetic patients. We proposed and developed an individualized, ubiquitous (U)-healthcare service using advanced information technology for more effective glucose control. Prior to our service initiation, we surveyed patient needs and other pertinent information.MethodsDuring August 2009, we conducted a 34-item questionnaire survey among patients with diabetes who were older than 40 years in two certain hospitals in Korea.ResultsThe mean age of the 228 participants was 61.2±9 years, and males made up 49.1% of the sample. Seventy-one percent replied that they wanted individualized healthcare service, and they also wanted their health information to be delivered through mobile devices such as a cellular phone or a personal digital assistant (40.4%). Most patients had never heard of U-healthcare services (81.1%); however, after explaining the concept, 71.1% of participants responded that they would use the service if it was provided. Despite their willingness, participants were concerned about technical difficulty in using the service (26.3%) as well as the cost of the service (29.8%).ConclusionThe current study suggests that more than 70% of diabetic patients are interested in using U-healthcare services. To encourage widespread use, the application program or device of U-healthcare services should be simple, easy to use and affordable while also including a policy for the protection of private information
Prostate Cancer Can Be Detected Even in Patients with Decreased PSA Less than 2.5 ng/ml after Treatment of Chronic Prostatitis
Prostate Cancer with Solitary Metastases to the Bilateral Testis
We present the case of an 81-year-old patient with testicular metastasis from prostate carcinoma. After the initial diagnosis of prostate cancer, he had an 8-year course of hormonal therapy and showed no clinical evidence of metastasis to other organs. Asymptomatic metastasis of prostate carcinoma to the testis is a rare clinical condition. We diagnosed his condition, based on histopathology following a subcapsular orchiectomy and transurethral resection of the prostate
Analgesic effect of highly reversible ω-conotoxin FVIA on N type Ca2+ channels
<p>Abstract</p> <p>Background</p> <p>N-type Ca<sup>2+ </sup>channels (Ca<sub>v</sub>2.2) play an important role in the transmission of pain signals to the central nervous system. ω-Conotoxin (CTx)-MVIIA, also called ziconotide (Prialt<sup>®</sup>), effectively alleviates pain, without causing addiction, by blocking the pores of these channels. Unfortunately, CTx-MVIIA has a narrow therapeutic window and produces serious side effects due to the poor reversibility of its binding to the channel. It would thus be desirable to identify new analgesic blockers with binding characteristics that lead to fewer adverse side effects.</p> <p>Results</p> <p>Here we identify a new CTx, FVIA, from the Korean <it>Conus Fulmen </it>and describe its effects on pain responses and blood pressure. The inhibitory effect of CTx-FVIA on N-type Ca<sup>2+ </sup>channel currents was dose-dependent and similar to that of CTx-MVIIA. However, the two conopeptides exhibited markedly different degrees of reversibility after block. CTx-FVIA effectively and dose-dependently reduced nociceptive behavior in the formalin test and in neuropathic pain models, and reduced mechanical and thermal allodynia in the tail nerve injury rat model. CTx-FVIA (10 ng) also showed significant analgesic effects on writhing in mouse neurotransmitter- and cytokine-induced pain models, though it had no effect on acute thermal pain and interferon-γ induced pain. Interestingly, although both CTx-FVIA and CTx-MVIIA depressed arterial blood pressure immediately after administration, pressure recovered faster and to a greater degree after CTx-FVIA administration.</p> <p>Conclusions</p> <p>The analgesic potency of CTx-FVIA and its greater reversibility could represent advantages over CTx-MVIIA for the treatment of refractory pain and contribute to the design of an analgesic with high potency and low side effects.</p
Delayed Diagnosis of an Intraurethral Foreign Body Causing Urosepsis and Penile Necrosis
Cases of self-inserted foreign bodies in the male urethra and urinary bladder are unusual. In most cases, the type of foreign body can be identified by taking a history or from radiological findings; sometimes, however, it is difficult to identify the foreign body because of decreased mental capacity of the patient or unknown radiological characteristics of the foreign body. We experienced a chronic alcoholic patient with septicemia and penile necrosis in whom a fragment of mirror glass had passed through the urethra into the bladder. The glass, 2 cm in length and 0.7 cm in diameter, was detected by cystoscopy and was removed by using a resectosope
Penile Growth in Response to Human Chorionic Gonadotropin (hCG) Treatment in Patients with Idiopathic Hypogonadotrophic Hypogonadism
Penile growth is under androgenic control. Human chorionic gonadotropin (hCG) has a stimulatory effect on testicular steroidogenesis and penile growth. The purpose of this study was to evaluate the effect of hCG treatment on the gonadal response and penile growth in male idiopathic hypogonadotrophic hypogonadism (IHH) presenting with micropenis. A total of 20 IHH patients who met the criteria for micropenis were included in this study. hCG (1,500-2,000 IU) was administrated intramuscularly, 3 times per week, for 8 weeks. Basic laboratory and hormonal indexes (including serum testosterone and LH levels), penis length (flaccid and stretched), and testicular volume were measured before and 24 weeks after hCG treatment. The patients' mean age was 18.9 years (range, 12 to 24 years). The mean serum testosterone level was significantly increased after hCG treatment (baseline, 2, 4, 12, and 24 weeks: 0.90±1.35 ng/ml, 1.77±1.31 ng/ml, 3.74±2.24 ng/ml, 5.49±1.70 ng/ml, and 5.58±1.75 ng/ml, respectively; p<0.05). Mean penile length also increased significantly 24 weeks after treatment (flaccid length: from 3.39±1.03 cm to 5.14±1.39 cm; stretched length: from 5.41±1.43 cm to 7.45±1.70 cm; p<0.001). Mean testicular volumes increased significantly as well (left: from 5.45 cc to 6.83 cc; right: from 5.53 cc to 7.03 cc). There were no remarkable adverse effects of the hCG treatment. The hCG treatment increased the serum testosterone level, penile length, and testicular volume in IHH patients. Our results suggest that hCG treatment has a beneficial effect on gonadal function and penile growth in patients with IHH presenting with micropenis
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