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991.
Won Hee Park Tae Young Shin Sang Min Yoon Soo-Hwan Park Yong Jin Kang Do Kyung Kim Jee-Young Han Do Hwan Seong 《Journal of Korean medical science》2014,29(7):1018-1020
Sparganosis is a parasitic infestation of human by plerocercoid larvae. Sparganum is usually reported to be found in the subcutaneous tissues as well as other organs, including scrotum. However, testicular sparganosis is extremely rare, because of strong capsule of tunica albuginea. An urban-living 54-yr-old Korean man presented with left scrotal pain for 6 yr. Both testes look normal physically. Ultrasonography revealed poorly defined, heterogeneous mass with increased echogenicity in the left testis. This case was misdiagnosed as testicular tumor and underwent orchiectomy, but was diagnosed as testicular sparganosis by histopathology. Sparganosis should be included for differential diagnosis of testis tumor in countries where sparganosis is prevalent.
Graphical Abstract
相似文献992.
Jin Seon Kwon Sung Won Kim Doo Yeon Kwon Seung Hun Park A. Reum Son Jae Ho Kim Moon Suk Kim 《Biomaterials》2014
Human turbinate mesenchymal stromal cells (hTMSCs) are an alternate source of adult stem cells for regenerative medicine. In this work, we demonstrated that hTMSCs are easily harvested from turbinate tissue using a minimal surgical procedure. hTMSCs showed positive expression of mesenchymal stem cell markers and proliferated at a high rate. The specific surface proteins of harvested hTMSCs were relatively tolerant of ex vivo manipulation in culture. hTMSCs exhibited osteogenic differentiation in vitro in the presence of osteogenic factors. To examine osteogenic differentiation of hTMSCs in vivo in an injectable hydrogel, cells were incorporated into a methoxy polyethylene glycol–polycaprolactone block copolymer (MPEG–PCL (MP)) solution simply by mixing. hTMSC-loaded MP solutions exhibited a temperature-dependent solution-to-gel phase transition. The hTMSC attached and grew well on in vitro- and in vivo-formed MP hydrogels. hTMSC-loaded MP solutions formed a hydrogel almost immediately upon injection into animals and the cells remained viable, even after 12 weeks. Injected hTMSCs in in situ-formed MP hydrogels differentiated into osteogenic cells, mainly in the presence of osteogenic factors. Differentiated osteoblasts were identified by Alizarin Red S, von Kossa, and alkaline phosphatase (ALP) staining, and osteonectin, osteopontin, and osteocalcin mRNA expression. To the best of our knowledge, this is the first study to show hTMSCs undergoing osteogenic differentiation in in vivo-formed MP hydrogels. In conclusion, hTMSCs could serve as adult stem cell sources and, when embedded in an in situ-formed hydrogel, may provide numerous benefits as a noninvasive alternative for bone tissue engineering applications. 相似文献
993.
994.
Min-Jeong Shin Eugene Shim Borum Kang Sungha Park Sang-Hak Lee Chi Young Shim Eunju Park Namsik Chung 《Yonsei medical journal》2009,50(6):757-763
Purpose
In the present study, we tested whether the presence of metabolic syndrome (MetS) would worsen the features of inflammation, plasma omega 3 fatty acid levels and antioxidant potential in treated hypertensive patients.Materials and Methods
Two groups were classified by the components of MetS: a reference group of treated hypertensive subjects: hypertension (HTN) group (n = 39) and with more than two additional MetS components: HTN with Mets group (n = 40). We further compared the parameters between HTN group and HTN with MetS group.Results
The results showed that age (p < 0.001) and body mass index (BMI) (p < 0.001) were significantly different between HTN group and HTN with MetS group. Age- and BMI-adjusted total radical trapping antioxidant potential (TRAP) (p < 0.01) was significantly lower, whereas age- and BMI-adjusted CD (p < 0.05) and interleukin (IL) 6 (p < 0.05) were significantly higher in HTN with MetS group than in HTN group. Moreover, HTN with MetS group had significantly lower levels of age- and BMI-adjusted plasma phospholipid eicosapentaenoic acid (EPA) than HTN group (p < 0.05). On the other hand, the levels of age- and BMI-adjusted intracellular cell adhesion molecule-1 (ICAM-1), adiponectin and high molecular weight (HMW)-adiponectin were not significantly different between the groups.Conclusion
In conclusion, our results showed increased inflammatory marker, reduced antioxidant potential and EPA levels in treated hypertensive patients in the presence of MetS, suggesting the importance of changes of therapeutic lifestyle to modify the features of MetS. 相似文献995.
Lee BI Oh SH Woo EJ Lee SY Cho MH Kwon O Seo JK Lee JY Baek WS 《Physics in medicine and biology》2003,48(13):1971-1986
In magnetic resonance electrical impedance tomography (MREIT), we try to reconstruct a cross-sectional resistivity (or conductivity) image of a subject. When we inject a current through surface electrodes, it generates a magnetic field. Using a magnetic resonance imaging (MRI) scanner, we can obtain the induced magnetic flux density from MR phase images of the subject. We use recessed electrodes to avoid undesirable artefacts near electrodes in measuring magnetic flux densities. An MREIT image reconstruction algorithm produces cross-sectional resistivity images utilizing the measured internal magnetic flux density in addition to boundary voltage data. In order to develop such an image reconstruction algorithm, we need a three-dimensional forward solver. Given injection currents as boundary conditions, the forward solver described in this paper computes voltage and current density distributions using the finite element method (FEM). Then, it calculates the magnetic flux density within the subject using the Biot-Savart law and FEM. The performance of the forward solver is analysed and found to be enough for use in MREIT for resistivity image reconstructions and also experimental designs and validations. The forward solver may find other applications where one needs to compute voltage, current density and magnetic flux density distributions all within a volume conductor. 相似文献
996.
Overexpression of S100A4 is closely related to the aggressiveness of gastric cancer 总被引:25,自引:0,他引:25
Cho YG Nam SW Kim TY Kim YS Kim CJ Park JY Lee JH Kim HS Lee JW Park CH Song YH Lee SH Yoo NJ Lee JY Park WS 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2003,111(5):539-545
Elevated levels of the calcium-binding protein S100A4 cause metastasis of benign rat mammary tumor cells. To investigate whether S100A4 plays an important role in the invasion and metastasis of gastric cancers, we examined the gene mutations in the coding regions and expression patterns of the S100A4 in gastric adenocarcinoma in Korea. Moderate to strong expression of S100A4 was found in 53 (68.8%) of the 77 gastric adenocarcinomas, whilst normal gastric epithelium either failed to stain or showed weak staining. Interestingly, S100A4 expression was more frequently observed in gastric cancer patients with advanced gastric cancer (p=0.039), positive lymph node metastasis (p=0.001), and peritoneal dissemination (p=0.022). No gene mutations were found in the analyzed genomic area in 77 gastric adenocarcinomas and 15 gastric cancer cell lines. We found one single nucleotide polymorphism without an amino acid change, A99G, in two cases. These data suggest that the overexpression of S100A4 may be closely related to the aggressiveness of gastric cancer in Korea. 相似文献
997.
A web-based real-time operating, management, and monitoring system for checking temperature and humidity within infant incubators using the Intranet has been developed and installed in the infant Intensive Care Unit (ICU). We have created a pilot system which has a temperature and humidity sensor and a measuring module in each incubator, which is connected to a web-server board via an RS485 port. The system transmits signals using standard web-based TCP/IP so that users can access the system from any Internet-connected personal computer in the hospital. Using this method, the system gathers temperature and humidity data transmitted from the measuring modules via the RS485 port on the web-server board and creates a web document containing these data. The system manager can maintain centralized supervisory monitoring of the situations in all incubators while sitting within the infant ICU at a work space equipped with a personal computer. The system can be set to monitor unusual circumstances and to emit an alarm signal expressed as a sound or a light on a measuring module connected to the related incubator. If the system is configured with a large number of incubators connected to a centralized supervisory monitoring station, it will improve convenience and assure meaningful improvement in response to incidents that require intervention. 相似文献
998.
A biodegradable nanofiber scaffold by electrospinning and its potential for bone tissue engineering 总被引:49,自引:0,他引:49
Microporous, non-woven poly( epsilon -caprolactone) (PCL) scaffolds were made by electrostatic fiber spinning. In this process, polymer fibers with diameters down to the nanometer range, or nanofibers, are formed by subjecting a fluid jet to a high electric field. Mesenchymal stem cells (MSCs) derived from the bone marrow of neonatal rats were cultured, expanded and seeded on electrospun PCL scaffolds. The cell-polymer constructs were cultured with osteogenic supplements under dynamic culture conditions for up to 4 weeks. The cell-polymer constructs maintained the size and shape of the original scaffolds. Scanning electron microscopy (SEM), histological and immunohistochemical examinations were performed. Penetration of cells and abundant extracellular matrix were observed in the cell-polymer constructs after 1 week. SEM showed that the surfaces of the cell-polymer constructs were covered with cell multilayers at 4 weeks. In addition, mineralization and type I collagen were observed at 4 weeks. This suggests that electrospun PCL is a potential candidate scaffold for bone tissue engineering. 相似文献
999.
Cytokine responses in mice infected with<Emphasis Type="Italic"> Clonorchis sinensis</Emphasis> 总被引:5,自引:0,他引:5
FVB and BALB/c mice show different morbidity, development of Clonorchis sinensis, and pathological changes following C. sinensis infection. FVB mice are susceptible and BALB/c mice are relatively more resistant to C. sinensis infection. To investigate the relationship between cytokine reaction and susceptibility to C. sinensis infection in FVB and BALB/c mice, we described both the patterns and kinetics of Th1 cytokines and Th2 cytokines in spleen cell culture. Interleukin (IL)-4 and IL-10 cytokine production in the culture supernatants of the concanavalin-A-stimulated spleen cells increased at 2–3 weeks post-infection in both strains. IL-5 production increased between 2 and 5 weeks post-infection in both strains, and reached a peak level at 2 weeks post-infection in BALB/c mice and 4 weeks post-infection in FVB mice. In contrast, gamma interferon (IFN-) production decreased between 2 and 4 weeks in both strains. IL-2 production increased slightly in BALB/c mice following infection, but was unchanged in FVB mice. IL-4 production over preinfection levels was significantly higher in FVB mice, whereas IFN-, IL-2, and IL-10 production were significantly higher in BALB/c mice. The levels of serum immunoglobulin E (IgE) and blood eosinophils in both mouse strains significantly increased between 3 and 6 weeks postinfection. Serum IgE levels were significantly higher in FVB mice than in BALB/c mice. The results of this study suggest that susceptibility to C. sinensis infection is associated with Th2 cytokine production, especially IL-4 which is predominant in relatively susceptible FVB mice. 相似文献
1000.
Sung Jae Shin Byung Soo Lee Won-Jung Koh Elizabeth J. B. Manning Kelly Anklam Srinand Sreevatsan Randall S. Lambrecht Michael T. Collins 《Journal of clinical microbiology》2010,48(11):4057-4062
Infections caused by the Mycobacterium avium complex (MAC) are on the rise in both human and veterinary medicine. A means of effectively discriminating among closely related yet pathogenetically diverse members of the MAC would enable better diagnosis and treatment as well as further our understanding of the epidemiology of these pathogens. In this study, a five-target multiplex PCR designed to discriminate MAC organisms isolated from liquid culture media was developed. This MAC multiplex was designed to amplify a 16S rRNA gene target common to all Mycobacterium species, a chromosomal target called DT1 that is unique to M. avium subsp. avium serotypes 2 and 3, to M. avium subsp. silvaticum, and to M. intracellulare, and three insertion sequences, IS900, IS901, and IS1311. The pattern of amplification results allowed determination of whether isolates were mycobacteria, whether they were members of the MAC, and whether they belonged to one of three major MAC subspecies, M. avium subsp. paratuberculosis, M. avium subsp. avium, and M. avium subsp. hominissuis. Analytical sensitivity was 10 fg of M. avium subsp. paratuberculosis genomic DNA, 5 to 10 fg of M. avium subsp. avium genomic DNA, and 2 to 5 fg of DNA from other mycobacterial species. Identification accuracy of the MAC multiplex was evaluated by testing 53 bacterial reference strains consisting of 28 different mycobacterial species and 12 nonmycobacterial species. Identification accuracy in a clinical setting was evaluated for 223 clinical MAC isolates independently identified by other methods. Isolate identification agreement between the MAC multiplex and these comparison assays was 100%. The novel MAC multiplex is a rapid, reliable, and simple assay for discrimination of MAC species and subspecies in liquid culture media.Since the early 1980s, there has been an increase in disease caused by organisms broadly categorized as nontuberculous mycobacteria (NTM), a generic term for mycobacteria not in the Mycobacterium tuberculosis complex and other than M. leprae (32). Of these NTM, Mycobacterium avium complex (MAC) species are the most common cause of human and animal disease globally (6, 14, 16, 24). The clinical relevance of the MAC in humans has been amplified in recent decades with the increasing population of immunocompromised individuals resulting from longer life expectancy, immunosuppressive chemotherapy, and the AIDS pandemic (27). The MAC is divided into two main species: M. avium and M. intracellulare. M. avium is further subdivided (per Turenne et al.) into four subspecies: M. avium subsp. avium, M. avium subsp. hominissuis, M. avium subsp. paratuberculosis, and M. avium subsp. silvaticum (39).Members of the family Mycobacteriaceae, comprising the MAC, differ in virulence and ecology. Those designated M. avium subsp. hominissuis are genomically diverse, low-virulence, opportunistic pathogens for both animals and humans. The majority of human M. avium subsp. hominissuis infections occur in HIV-immunocompromised people, immunocompetent persons with underling pulmonary disease, and children with cystic fibrosis (2, 12, 17). Considered ubiquitous in the environment (the most likely source of infection for humans), M. avium subsp. hominissuis has been isolated from water, soil, and dust (9). Domestic water distribution systems have been reported as possible sources of M. avium subsp. hominissuis infections in hospitals, homes, and commercial buildings (26, 27). In animals, M. avium subsp. hominissuis is found as a cause of lymphadenitis of the head and mesenteric lymph nodes of swine recognized at slaughter.Mycobacterium avium subsp. avium has long been recognized as a primary pathogen causing avian tuberculosis in wild and domestic birds (37, 38). Members of this subspecies also sporadically cause disease in other animals (6, 15, 30).For veterinarians, the MAC member of greatest importance is M. avium subsp. paratuberculosis. This MAC member causes a chronic granulomatous enteritis called Johne''s disease or paratuberculosis, most often in ruminants (16, 22, 31). Mycobacterium avium subsp. paratuberculosis is capable of infecting and causing disease a wide array of animal species, including nonhuman primates, without need of immunosuppressive coinfections. The herd-level prevalence of M. avium subsp. paratuberculosis infections in dairy cattle exceeds 50% in most major dairy product-producing countries (29, 31). Two systematic reviews and meta-analyses report a consistent association of M. avium subsp. paratuberculosis with Crohn''s disease, and the zoonotic potential of M. avium subsp. paratuberculosis continues to be a controversial subject discussed in the literature (1, 11). Unlike for most other M. avium subspecies, isolation of M. avium subsp. paratuberculosis requires the addition of the siderophore mycobactin to culture media and prolonged culture incubation for successful isolation from a tissue, soil, or fecal samples (43). After this lengthy incubation period with special media, resultant acid-fast organisms then need to be accurately identified.Unlike the M. avium subspecies, whose type strains were obtained from nonhuman hosts, the type strain of M. intracellulare (ATCC 13950) was isolated from a human, specifically a child who died from disseminated disease. Recently, numerous isolates considered to be M. intracellulare were reclassified as M. chimaera sp. nov. as part of the MAC (35). Few of these isolates were found to be clinically relevant, suggesting that this MAC species has low pathogenicity, and this factor is crucial to therapeutic decision making. Mycobacterium intracellulare appears to have a distinct environmental niche, more prevalent in biofilms and at significantly higher CFU numbers than M. avium (10, 36). It accounts for more documented human infections than M. avium subsp. hominissuis in several countries, including South Korea and Japan (19, 20, 23).Contemporary methods for MAC identification, e.g., high-performance liquid chromatography (HPLC) of cell wall mycolic acids, and genetic probes based on rRNA targets, e.g., AccuProbe, cannot discriminate among M. avium subspecies (2, 9). Given the differences in pathogenicity among M. avium subspecies and the implications regarding the infection source, a practical and accurate method of simply identifying M. avium subspecies is needed (13, 25, 35). In this study, we describe the specificity, discrimination capacity, and sensitivity of a novel five-target PCR, called the MAC multiplex, using a wide array of reference and clinical MAC isolates and numerous nonmycobacterial organisms. 相似文献