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21.
Ohsang Kwon Kee Jeong Bae Hyun Sik Gong Jihyeung Kim Goo Hyun Baek 《Journal of clinical densitometry》2021,24(1):88-93
Introduction: Computed tomography (CT) can be used to assess bone status with measurement of Hounsfield unit (HU). The objective of this study was to evaluate whether HU of muscle might be associated with parameters of bone and muscle status. Methods: We reviewed 71 women aged over 50 yr of age who had distal radius fracture and underwent CT evaluation of affected wrist. We assessed HUs of forearm flexor muscles (flexor digitorum superficialis) and thenar muscles and bone HUs at the capitate and the ulnar head. Other parameters included femur neck and lumbar bone mineral density (BMD), upper extremity lean mass, hand grip strength, and muscle fiber cross-sectional area. We performed correlation analyses to determine associations between variables. Results: Thenar and forearm muscle HUs were significantly correlated with each other, but not with other parameters. HUs of the capitate and ulnar head were positively correlated with femur neck and lumbar BMDs and inversely correlated with age. Ulnar head HU was positively correlated hand grip strength. Conclusions: HUs of forearm and thenar muscles did not show significant correlations with bone or muscle parameters, although bone HUs correlated well with bone mineral densities. These results support the opportunistic use of CT for evaluating bone fragility. Clinical usefulness of muscle HU measurement needs further studies. 相似文献
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23.
Pil Whan Yoon Jong Yeal Kang Chul-Ho Kim Soong Joon Lee Jeong Joon Yoo Hee Joong Kim Sung Keun Kang Ju Hyeon Min Kang Sup Yoon 《Clinics in Orthopedic Surgery》2021,13(1):37
BackgroudOutcomes of traditional treatment for osteonecrosis of the femoral head (ONFH) are not always satisfactory. Hence, cell-supplementation therapy has been attempted to facilitate necrotic-tissue regeneration. Adipose-derived mesenchymal stem cell (ADMSC) transplantation is potentially advantageous over bone marrow-derived MSC implantation, but its outcomes for ONFH remain unclear. The aim of this study was to determine 2-year radiological and clinical outcomes of culture-expanded autologous ADMSC implantation for ONFH.MethodsEighteen hips with necrotic lesions involving ≥ 30% of the femoral head were included. ADMSCs were harvested by liposuction and culture expanded for 3 passages over 3 weeks. With a 6-mm single drilling, ADMSCs were implanted into the necrotic zone. All patients underwent magnetic resonance imaging (MRI), single-photon emission computed tomography/computed tomography (SPECT/CT) at screening and 6 months, 12 months, and 24 months postoperatively. The primary outcome was the change in the size of necrotic area on MRI. Secondary outcomes were changes in clinical scores and radioisotope uptake on SPECT/CT. Conversion total hip arthroplasty (THA) was defined as the endpoint.ResultsPreoperatively, the necrotic lesion extent was 63.0% (38.4%–96.7%) of the femoral head. The mean Harris hip score was 89.2, the University of California at Los Angeles (UCLA) score was 5.6, and Western Ontario and McMaster Universities Arthritis index (WOMAC) was 79.4. Three patients underwent THA and 1 patient died in an accident. Finally, 11 patients (14 hips) were available for ≥ 2-year follow-up. At the last follow-up, no surgery-related complications occurred, and 14 of 17 hips (82%) were able to perform daily activities without THA requirement. There was no significant decrease in lesion size between any 2 intervals on MRI. However, widening of high signal intensity bands on T2-weighted images inside the necrotic lesion was observed in 9 of 14 hips (64%); 11 of 14 hips (79%) showed increased vascularity on SPECT/CT at 2 years postoperatively. No significant differences were observed between preoperative and 24-month mean Harris hip score (89.2 vs. 88.6), WOMAC (79.4 vs. 75.7), and UCLA score (5.6 vs. 6.2).ConclusionsOur outcomes suggest that culture-expanded ADMSC implantation is a viable option for ONFH treatment without adverse events. 相似文献
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25.
An efficient synthesis of 3-(E)-hydroxy- and 3-(E)-acetoxypropenylcephem derivatives, key intermediates for the synthesis of 3-(E)-propenylcephalosporins was achievedvia Stille coupling reaction of 3-trifloxycephem with 3-(E)-tributylstannylallylic alcohol. 相似文献
26.
The studies were carried out to evaluate the constituents in the aerial part of Aconitum chiisanense (Ranunculaceae). From the butanol fraction of the methanol extract, kaempferol 3- O-beta-glucopyranoside-7- O-(6-trans-caffeoyl)-beta-glucopyranosyl-(1-->2)-alpha-rhamnopyranoside (I), quercetin 3- O-beta-glucopyranoside-7- O-(6-trans-caffeoyl)-beta-glucopyranosyl-(1-->2)-alpha-rhamnopyranoside (II), kaempferol 3- O-beta-glucopyranoside-7- O-(6-trans-feruloyl)-beta-glucopyranosyl-(1-->2)-alpha-rhamnopyranoside (III), kaempferol 3- O-beta-glucopyranoside-7- O-(6-benzoyl)-beta-glucopyranosyl-(1-->2)-alpha-rhamnopyranoside (IV), kaempferol 7- O-(6-trans)-caffeoyl)-beta-glucopyranosyl-(1-->2)-alpha-rhamnopyranoside (V), and kaempferol 7- O-beta-glucopyranosyl-(1-->2)-alpha-rhamnopyranoside (VI) were isolated and identified on the basis of their physicochemical and spectroscopic evidence (UV, IR, FAB(-)MS, (1)H-NMR, (13)C-NMR, (1)H- (1)H COSY, HMQC and HMBC). New compounds I-VI were named chiisanin (I), chiiribanin (II), chiiribaconin (III), chiirin (IV), chiiricanin (V), and chiirirhamnin (VI), respectively. 相似文献
27.
AB-type amphiphilic copolymers (abbreviated as LE) composed of poly (L-leucine) (PLL) as the A component and poly (ethylene
oxide) (PEO) as the B component were synthesized by the ring-opening polymerization of L-leucine N-carboxy-anhydride initiated
by methoxy polyoxyethylene amine (Me-PEO-NH2) and characterized. Core-shell type nanoparticles were prepared by the diafiltration method. Particle size distribution obtained
by dynamic light scattering was dependent on PLL composition and the size for LE-1, LE-2 and LE-3 was 369.6±267, 523.4±410
and 561.2±364 nm, respectively. Shapes of the nanoparticles observed by transmission electron microscope (TEM) were almostly
spherical. The critical micelle concentration (CMC) of the nanoparticles determined by a fluorescence probe technique was
dependent on the composition of hydrophobic PLL, and the CMC for LE-1, LE-2 and LE-3 was 2. 0×10−6, 1.7×10−6 and 1.5×10−6 (mol/l), respectively. Clonazepam release from core-shell type nanoparticles in vitro was dependent on PLL composition and
drug loading content. 相似文献
28.
Pretreatment of low dose radiation reduces radiation-induced apoptosis in mouse lymphoma (EL4) cells
Induction of an adaptive response to ionizing radiation in mouse lymphoma (EL4) cells was studied by using cell survival fraction
and apoptotic nucleosomal DNA fragmentation as biological end points. Cells in early log phase were pre-exposed to low dose
of γ-rays (0.01 Gy) 4 or 20 hrs prior to high dose γ-ray (4, 8 and 12 Gy for cell survival fraction analysis; 8 Gy for DNA
fragmentation analysis) irradiation. Then cell survival fractions and the extent of DNA fragmentation were measured. Significant
adaptive response, increase in cell survival fraction and decrease in the extent of DNA fragmentation were induced when low
and high dose γ-ray irradiation time interval was 4 hr. Addition of protein or RNA synthesis inhibitor, cycloheximide or 5,6-dichloro-1-β-d-ribofuranosylbenzimidazole
(DRFB), respectively during adaptation period, the period from low dose γ-ray irradiation to high dose γ-ray irradiation,
was able to inhibit the induction of adaptive response, which is the reduction of the extent DNA fragmentation in irradiated
EL4 cells. These data suggest that the induction of adaptive response to ionizing radiation in EL4 cells required both protein
and RNA synthesis. 相似文献
29.
Baek NI Kim JM Park JH Ryu JH Kim DS Lee YH Park JD Kim SI 《Archives of pharmacal research》1997,20(3):280-282
A genuine dammarane-glycoside, named as ginsenoside Rs3, was isolated from the MeOH extracts of Korean red ginseng (Panax ginseng C.A. Meyer) through repeated silica gel column chromatographies and its chemical structure was determined as (20S)-protopanaxadiol 3-O-[6″-O-acetyl-β-D-glucopyranosyl (1→2)-β-D-glucopyranoside on the basis of several spectral and physical evidences including HMBC
and FAB-MS. 相似文献
30.
Ahn YK Park JC Park WS Kim NH Kim JW Kim SH Cho JH Jeong MH Cho JG Kang JC 《Journal of Korean medical science》1999,14(5):571-574
Epicardial fat may anteriorly produce an echo-free space that can be mistaken for pericardial fluid. We recently experienced a 67-year-old woman with prominent epicardial fat which was presented as an echogenic tumor-like mass. She underwent open pericardiostomy to relieve large amount of pericardial effusion. Operative findings revealed only prominent epicardial fat. Biopsy of the pericardial and fat tissues revealed an inflammation and normal fat cells without any malignant cell infiltration. 相似文献