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81.
We used a dual-chamber culture system separated by a dialysis membrane to test the efficiency of expansion of whole cord blood and cell fractions. We found that expansion of progenitor cells was more efficient from whole blood than from purified CD34+ or partially purified mononuclear cell fractions. 相似文献
82.
A Mi Kim Jong Woon Kim Yoon Ha Kim Tae Young Kim Hyun Kyung Ryu Myeong Gyun Choi 《The Journal of international medical research》2021,49(3)
IntroductionSonography and magnetic resonance imaging (MRI) may be helpful to obtain an accurate diagnosis of acute abdominal pain in pregnancy. Adnexal torsion presenting in the first or second trimester can be confirmed and treated through laparoscopic surgery; however laparoscopic surgery in the third trimester can be difficult owing to the large uterus, and a gridiron incision can be useful.Case Report/Case presentationAn 18-year-old gravida 1, para 0 (G1P0) woman at 30 + 4 weeks of gestation presented with sudden-onset cyclic pain in the right lower quadrant. Abdominal ultrasonography showed a normal appendix, and MRI showed a normal appendix and normal ovaries. The patient’s prominent tender point was marked and compared with the MR images, which confirmed the mark as the position of the right ovary. Laparotomy was performed through a gridiron incision, and a folded right ovary was identified. The ovary was unfolded, and TachoSil® and Surgicel® were used to maintain the unfolded position. The patient’s pain resolved, and her postoperative course was uneventful. She delivered a healthy, 2540-g male baby at 35 weeks’ gestation.Discussion/ConclusionsA gridiron incision was useful to treat a folded ovary in the third trimester and to evaluate the adnexa and minimize uterine manipulation. 相似文献
83.
Shrikant R Mulay Dana Thomasova Mi Ryu Onkar P Kulkarni Adriana Migliorini Hauke Bruns Regina Gröbmayr Elena Lazzeri Laura Lasagni Helen Liapis Paola Romagnani Hans‐Joachim Anders 《The Journal of pathology》2013,230(3):322-335
Podocyte apoptosis as a pathway of podocyte loss is often suspected but rarely detected. To study podocyte apoptosis versus inflammatory forms of podocyte death in vivo, we targeted murine double minute (MDM)‐2 for three reasons. First, MDM2 inhibits p53‐dependent apoptosis; second, MDM2 facilitates NF‐κB signalling; and third, podocytes show strong MDM2 expression. We hypothesized that blocking MDM2 during glomerular injury may trigger p53‐mediated podocyte apoptosis, proteinuria, and glomerulosclerosis. Unexpectedly, MDM2 blockade in early adriamycin nephropathy of Balb/c mice had the opposite effect and reduced intra‐renal cytokine and chemokine expression, glomerular macrophage and T‐cell counts, and plasma creatinine and blood urea nitrogen levels. In cultured podocytes exposed to adriamycin, MDM2 blockade did not trigger podocyte death but induced G2/M arrest to prevent aberrant nuclear divisions and detachment of dying aneuploid podocytes, a feature of mitotic catastrophe in vitro and in vivo. Consistent with these observations, 12 of 164 consecutive human renal biopsies revealed features of podocyte mitotic catastrophe but only in glomerular disorders with proteinuria. Furthermore, delayed MDM2 blockade reduced plasma creatinine levels, blood urea nitrogen, tubular atrophy, interstitial leukocyte numbers, and cytokine expression as well as interstitial fibrosis. Together, MDM2‐mediated mitotic catastrophe is a previously unrecognized variant of podocyte loss where MDM2 forces podocytes to complete the cell cycle, which in the absence of cytokinesis leads to podocyte aneuploidy, mitotic catastrophe, and loss by detachment. MDM2 blockade with nutlin‐3a could be a novel therapeutic strategy to prevent renal inflammation, podocyte loss, glomerulosclerosis, proteinuria, and progressive kidney disease. Copyright © 2013 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. 相似文献
84.
Seung Min Kim Jin Hwan Park Hyun Sung Lee Won Bin Kim Jung Min Ryu Ho Jae Han Sang Ho Choi 《Infection and immunity》2013,81(10):3721-3730
Quorum sensing is a cell-to-cell communication system known to control many bacterial processes. In the present study, the functions of quorum sensing in the pathogenesis of Vibrio vulnificus, a food-borne pathogen, were assessed by evaluating the virulence of a mutant deficient in SmcR, a quorum-sensing regulator and homologue of LuxR. When biofilms were used as an inoculum, the smcR mutant was impaired in virulence and colonization capacity in the infection of mice. The lack of SmcR also resulted in decreased histopathological damage in mouse jejunum tissue. These results indicated that SmcR is essential for V. vulnificus pathogenesis. Moreover, the smcR mutant exhibited significantly reduced biofilm detachment. Upon exposure to INT-407 host cells, the wild type, but not the smcR mutant, revealed accelerated biofilm detachment. The INT-407 cells increased smcR expression by activating the expression of LuxS, an autoinducer-2 synthase, indicating that host cells manipulate the cellular level of SmcR through the quorum-sensing signaling of V. vulnificus. A whole-genome microarray analysis revealed that the genes primarily involved in biofilm detachment and formation are up- and downregulated by SmcR, respectively. Among the SmcR-regulated genes, vvpE encoding an elastolytic protease was the most upregulated, and the purified VvpE appeared to dissolve established biofilms directly in a concentration-dependent manner in vitro. These results suggest that the host cell-induced SmcR enhances the detachment of V. vulnificus biofilms entering the host intestine and thereby may promote the dispersal of the pathogen to new colonization loci, which is crucial for pathogenesis. 相似文献
85.
86.
Jeehae Han Seungjin Ryu David M. Moskowitz Devorah Rothenberg Daniel J. Leahy Gil Atzmon Nir Barzilai Yousin Suh 《Mechanisms of ageing and development》2013
Despite evidence of a substantial genetic component, the genetic factors that underlie longevity in humans remain to be identified. Previous genome-wide linkage and association studies have not found strong evidence for the contribution of common variants besides the APOE gene, suggesting the role of rare variants in human longevity. To discover rare variants that might contribute to longevity, we selected 988 candidate genes and performed a pilot study to identify novel non-synonymous variants in 6 Ashkenazi Jewish centenarians older than 105. Our candidate genes act in pathways implicated in aging and longevity, including neurodegeneration, cognitive function, lipid metabolism, DNA repair, and genome maintenance. By implementing custom-designed Agilent SureSelect target capture and next-generation sequencing, we discovered a total of 89 novel non-synonymous SNPs (nsSNPs) and validated 51 nsSNPs by iPLEX MassArray assays. Genotyping analysis of these novel SNPs in 410 Ashkenazi Jewish controls and 390 centenarians showed significant enrichment (5.3 fold, p = 0.02) of the p.Y318C variant in PMS2 and significant depletion (7.5 fold, p = 0.04) of the p.V465A variant in GABRR3 in centenarians compared to controls. Our study presents the potential of targeted next-generation sequencing for discovery of rare but functional genetic variation which may lead to exceptional longevity in humans. 相似文献
87.
88.
Yoshihiro Omura Hirotoshi Imamura Shoichi Tani Hidemitsu Adachi Ryu Fukumitsu Tadashi Sunohara Nobuyuki Fukui Natsuhi Sasaki Tatsumaru Fukuda Tomoaki Akiyama Shinji Kajiura Masashi Shigeyasu Kento Asakura Ryo Horii Nobuyuki Sakai 《Journal of stroke and cerebrovascular diseases》2021,30(8):105853
BackgroundCopolymer (Onyx) embolization is an effective treatment for dural arteriovenous fistula (dAVF), however, some dAVFs have multiple, high-flow feeding vessels, resulting in insufficient embolization. For the treatment of such patients, we have developed a novel flow-control technique, the ‘damp-and-push technique’. The purpose of this study was to evaluate the technical efficiency and safety of this technique.MethodsSeven patients who had been diagnosed with intracranial dAVF were treated by transarterial Onyx embolization using the damp-and-push technique between 2016 and 2019. This technique was designed to reduce blood flow to the shunt site using a balloon catheter in the major feeding vessel other than the one injected with Onyx, leading to better Onyx penetration and enabling more controlled embolization of complex dAVFs. Retrospectively collected data were reviewed to assess the occlusion rates and clinical outcomes.ResultsThe dAVF was at a transverse sinus-sigmoid sinus junction in four patients, in the superior sagittal sinus in two, and in the tentorium in one. Five cases were Cognard type Ⅱb and two cases were Cognard type Ⅳ. All the patients were treated by transarterial Onyx injection via the main feeding vessel, combined with flow reduction in the other main feeding vessel using a balloon catheter. Complete occlusion was achieved in six patients and elimination of cerebral venous reflux was achieved in all the patients. There were no immediate or delayed post-interventional complications.ConclusionsTransarterial Onyx embolization of dAVF using the damp-and-push technique is safe and yields a high complete occlusion rate. 相似文献
89.
Bacteriophage chi is a well-known phage that infects pathogens such as E. coli, Salmonella, and Serratia via bacterial flagella. To further understand its host-phage interaction and infection mechanism via host flagella, the genome was completely sequenced and analyzed. The phage genome contains 59,407-bp-length DNA with a GC content of 56.51 %, containing 75 open reading frames (ORFs) with no tRNA genes. Its annotation and functional analysis revealed that chi is evolutionarily very closely related to Enterobacter phage Enc34 and Providencia phage Redjac. However, most of the annotated genes encode hypothetical proteins, indicating that further genomic study of phage chi is required to elucidate the bacterial-flagellum-targeting infection mechanism of phage chi. 相似文献
90.
Joo Won Chung Sung Ho Ryu Jung Hyun Jo Jeong Youp Park Sak Lee Seung Woo Park Si Young Song Jae Bock Chung 《Yonsei medical journal》2013,54(1):154-159