Proto-Model of an Infrared Wide-Field Off-Axis Telescope

We develop a proto-model of an off-axis reflective telescope for infrared wide-field observations based on the design of Schwarzschild-Chang type telescope. With only two mirrors, this design achieves an entrance pupil diameter of 50 mm and an effective focal length of 100 mm. We can apply this design to a mid-infrared telescope with a field of view of 8 deg X 8 deg. In spite of the substantial advantages of off-axis telescopes in the infrared compared to refractive or on-axis reflective telescopes, it is known to be difficult to align the mirrors in off-axis systems because of their asymmetric structures. Off-axis mirrors of our telescope are manufactured at the Korea Basic Science Institute (KBSI). We analyze the fabricated mirror surfaces by fitting polynomial functions to the measured data. We accomplish alignment of this two-mirror off-axis system using a ray tracing method. A simple imaging test is performed to compare a pinhole image with a simulated prediction.Comment: 14 pages, 16 figure

Acidic pH shock induces the expressions of a wide range of stress-response genes

<p>Abstract</p> <p>Background</p> <p>Environmental signals usually enhance secondary metabolite production in <it>Streptomycetes </it>by initiating complex signal transduction system. It is known that different sigma factors respond to different types of stresses, respectively in <it>Streptomyces </it>strains, which have a number of unique signal transduction mechanisms depending on the types of environmental shock. In this study, we wanted to know how a pH shock would affect the expression of various sigma factors and shock-related proteins in <it>S. coelicolor </it>A3(2).</p> <p>Results</p> <p>According to the results of transcriptional and proteomic analyses, the major number of sigma factor genes were upregulated by an acidic pH shock. Well-studied sigma factor genes of <it>sigH </it>(heat shock), <it>sigR </it>(oxidative stress), <it>sigB </it>(osmotic shock), and <it>hrdD </it>that play a major role in the secondary metabolism, were all strongly upregulated by the pH shock. A number of heat shock proteins including the DnaK family and chaperones such as GroEL2 were also observed to be upregulated by the pH shock, while their repressor of <it>hspR </it>was strongly downregulated. Oxidative stress-related proteins such as thioredoxin, catalase, superoxide dismutase, peroxidase, and osmotic shock-related protein such as vesicle synthases were also upregulated in overall.</p> <p>Conclusion</p> <p>From these observations, an acidic pH shock was considered to be one of the strongest stresses to influence a wide range of sigma factors and shock-related proteins including general stress response proteins. The upregulation of the sigma factors and shock proteins already found to be related to actinorhodin biosynthesis was considered to have contributed to enhanced actinorhodin productivity by mediating the pH shock signal to regulators or biosynthesis genes for actinorhodin production.</p

Stimulation-Induced Side Effects of Deep Brain Stimulation in the Ventralis Intermedius and Posterior Subthalamic Area for Essential Tremor

Deep brain stimulation (DBS) targeting the ventralis intermedius (VIM) nucleus of the thalamus and the posterior subthalamic area (PSA) has been shown to be an effective treatment for essential tremor (ET). The aim of this study was to compare the stimulation-induced side effects of DBS targeting the VIM and PSA using a single electrode. Patients with medication-refractory ET who underwent DBS electrode implantation between July 2011 and October 2020 using a surgical technique that simultaneously targets the VIM and PSA with a single electrode were enrolled in this study. A total of 93 patients with ET who had 115 implanted DBS electrodes (71 unilateral and 22 bilateral) were enrolled. The Clinical Rating Scale for Tremor (CRST) subscores improved from 20.0 preoperatively to 4.3 (78.5% reduction) at 6 months, 6.3 (68.5% reduction) at 1 year, and 6.5 (67.5% reduction) at 2 years postoperation. The best clinical effect was achieved in the PSA at significantly lower stimulation amplitudes. Gait disturbance and clumsiness in the leg was found in 13 patients (14.0%) upon stimulation of the PSA and in significantly few patients upon stimulation of the VIM (p = 0.0002). Fourteen patients (15.1%) experienced dysarthria when the VIM was stimulated; this number was significantly more than that with PSA stimulation (p = 0.0233). Transient paresthesia occurred in 13 patients (14.0%) after PSA stimulation and in six patients (6.5%) after VIM stimulation. Gait disturbance and dysarthria were significantly more prevalent in patients undergoing bilateral DBS than in those undergoing unilateral DBS (p = 0.00112 and p = 0.0011, respectively). Paresthesia resolved either after reducing the amplitude or switching to bipolar stimulation. However, to control gait disturbance and dysarthria, some loss of optimal tremor control was necessary at that particular electrode contact. In the present study, the most common stimulation-induced side effect associated with VIM DBS was dysarthria, while that associated with PSA DBS was gait disturbance. Significantly, more side effects were associated with bilateral DBS than with unilateral DBS. Therefore, changing active DBS contacts to simultaneous targeting of the VIM and PSA may be especially helpful for ameliorating stimulation-induced side effects

Human AP endonuclease suppresses DNA mismatch repair activity leading to microsatellite instability

The multifunctional mammalian apurinic/apyrimidinic (AP) endonuclease (APE) participates in the repair of AP sites in the cellular DNA as well as participating in the redox regulation of the transcription factor function. The function of APE is considered as the rate-limiting step in DNA base excision repair. Paradoxically, an unbalanced increase in APE protein leads to genetic instability. Therefore, we investigated the mechanisms of genetic instability that are induced by APE. Here, we report that the overexpression of APE protein disrupts the repair of DNA mismatches, which results in microsatellite instability (MSI). We found that expression of APE protein led to the suppression of the repair of DNA mismatches in the normal human fibroblast cells. Western blot analysis revealed that hMSH6 protein was markedly reduced in the APE-expressing cells. Moreover, the addition of purified Mutα (MSH2 and MSH6 complex) to the extracts from the APE-expressing cells led to the restoration of mismatch repair (MMR) activity. By performing MMR activity assay and MSI analysis, we found that the co-expression of hMSH6 and APE exhibited the microsatellite stability, whereas the expression of APE alone generated the MSI-high phenotype. The APE-mediated decrease in MMR activity described here demonstrates the presence of a new and highly effective APE-mediated mechanism for MSI

Molecular Imaging of High-Risk Atherosclerotic Plaques: Is It Clinically Translatable?

The explosive epidemics of diabetes and obesity as well as an aging population have led to cardiovascular diseases as the leading cause of world-wide morbidity and mortality beyond cancer. The recent introduction of drug-eluting stents and medications such as statins, dual anti-platelet therapy, and angiotensin converting enzyme inhibitors has dramatically improved clinical outcomes in patients with cardiovascular diseases. However, mortality is still increasing despite state-of-the-art therapeutics, as current diagnostic and therapeutic strategies against cardiovascular disease center on "locking the barn door after the horse has been stolen". Novel diagnostic solutions that identify individuals at risk before the disease is overt are needs. Imaging approaches that visualize molecular targets rather than anatomical structures aim to illuminate vital molecular and cellular aspects of atherosclerosis biology in vivo. Recent technological advances in small animal imaging systems and dedicated targeted/activatable molecular imaging probes have positioned molecular imaging to greatly impact atherosclerosis imaging in the next decade. However, several issues must be addressed before its clinical translation

Bilateral adrenal pheochromocytoma with a germline L790F mutation in the RET oncogene

About ten percent of pheochromocytomas are associated with familial syndrome. Hereditary pheochromocytoma has characteristics of early onset, multifocality and bilaterality. We experienced a case of 44-year-old man with bilateral pheochromocytoma without evidence of medullary thyroid cancer. Genetic test detected a L790F germline mutation of RET oncogene. The author found a necessity for genetic tests in cases of young-age, bilateral pheochromocytoma

Management of Patients with Ischemic Heart Disease in Spine Surgery

In ischemic heart disease (IHD), the myocardium does not receive enough blood and oxygen. Although the IHD-related mortality rate is decreasing, the risk remains and is a major predictor of cardiac complications following noncardiac surgery. Given the increase in the older population, the number of patients with spinal diseases requiring surgery is increasing. Among these patients, those with underlying IHD or a high risk of cardiac complications before and after surgery are also increasing. Given that cardiac complications following spinal surgery are associated with delayed patient recovery and even death, spinal surgeons should be knowledgeable about overall patient management, including medication therapy in those at high risk of developing perioperative cardiac complications for successful patient care. Before surgery, the underlying medical conditions of patients should be evaluated. Patients with a history of myocardial infarction should be checked for a history of surgical treatments, and the anticoagulant dose should be controlled depending on the surgery type. In addition, the functional status of patients must be examined before surgery. Functional status can be assessed according to the metabolic equivalent of task (MET). More preoperative cardiac examinations are needed for patients who are unable to perform four METs in daily because of the high risk of postoperative cardiac complications. Patients with a history of IHD require appropriate preoperative management and further postoperative evaluation. When considering surgery, spinal surgeons should be knowledgeable about patient care before and after surgery

大韓獸醫學會誌 (2015) 第 55 卷 第 1 號

Abstract : A 14-year-old, 7.4 kg, neutered male mongrel dog presented with vomiting, anorexia, and hematuria starting 3 days prior to admission. Serum biochemical profiles indicated severe azotemia. Computed tomography revealed loss of normal left kidney structure. The organ was 1.5 to 2 times larger than the right kidney with mixed attenuation. Histopathologic examination was performed after nephrectomy. The renal mass and mesenteric membrane were positive for vimentin and stained blue with Masson&apos;s trichrome. In conclusion, this was a rare occurrence of primary renal fibrosarcoma, most likely originated from the renal capsule, with local invasion into the mesenteric membrane