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1.
Nanoscale ; 2020 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-32391820

RESUMO

Herein, we report for the first time the successful preparation of thiometallate-based precursors for use in a bottom-up synthetic process of supported Pt and PtNi nanoparticle catalyst. This precursor enabled the monodisperse synthesis of supported Pt nanoparticles and the in situ formation of S, which were caught directly in a collection system by the nanoparticle synthetic processes consisting of impregnation and thermal processes. S is proven to act as a capping agent in generating highly stable nanoparticles with the size ranging from 2 nm to 3 nm and further favors the formation of monodispersed particles by solid-state digestive ripening. The proposed synthetic methodology can be applied to high-quality PtNi alloy nanoparticle systems. The current route is readily scalable, and multi-gram quantities can be prepared. The prepared carbon-supported Pt and PtNi nanoparticles were characterized as electrocatalysts for the oxygen reduction reaction and exhibited superior performance and durability to commercial Pt/C.

2.
Am J Sports Med ; 48(7): 1696-1701, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32396461

RESUMO

BACKGROUND: The aging process is accompanied by several conditions that could affect the outcome of meniscal allograft transplantation (MAT). These conditions have made it difficult for clinicians to determine the effect of chronologic age on survivorship after MAT. HYPOTHESIS: Advanced age does not have an adverse effect on survivorship of MAT when controlling for age-related factors, such as cartilage status and time from previous meniscectomy. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: The records of 264 consecutive patients who underwent primary medial or lateral MAT were reviewed. To check whether there was a difference in MAT survivorship according to age, a cutoff value was calculated from a time-dependent receiver operating characteristic curve. Survival rates, as well as clinical improvement as determined using the Lysholm score, were compared between groups divided by the cutoff value. Patients were matched for cartilage status and elapsed time from previous meniscectomy. Differences in survivorship and clinical outcomes were assessed between the matched groups. RESULTS: A time-dependent receiver operating characteristic curve showed that the difference in MAT survivorship was maximized with a cutoff age of 43 years. Kaplan-Meier analysis showed a significant difference in MAT survivorship between the older and younger groups (log-rank test, P = .01). However, after matching for cartilage status and time from previous meniscectomy, which left 56 patients per group, there was no significant difference in MAT survivorship (log-rank test, P = .10) between the groups. Regarding clinical outcomes, the mean Lysholm scores were not significantly different between the older and younger groups (P = .19, before matching; P = .39, after matching). CONCLUSION: MAT survivorship was more affected by age-related prognostic factors, such as cartilage status and time from previous meniscectomy, than age itself. Clinical outcomes did not show differences according to age, either.

3.
J Mov Disord ; 2020 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-32344993

RESUMO

While many infectious disorders are unknown to most neurologists, COVID-19 is very different. It has impacted neurologists and other health care workers, not only in our professional lives but also through the fear and panic within our own families, colleagues, patients and their families, and even in the wider public. COVID-19 affects all sorts of individuals, but the elderly with underlying chronic conditions are particularly at risk of severe disease, or even death. Parkinson's disease (PD) shares a common profile as an age-dependent degenerative disorder, frequently associated with comorbidities, particularly cardiovascular diseases, so PD patients will almost certainly fall into the high-risk group. Therefore, the aim of this review is to explore the risk of COVID-19 in PD based on the susceptibility to severe disease, its impact on PD disease severity, potential long-term sequelae, and difficulties of PD management during this outbreak, where neurologists face various challenges on how we can maintain effective care for PD patients without exposing them, or ourselves, to the risk of infection. It is less than six months since the identification of the original COVID-19 case on New Year's Eve 2019, so it is still too early to fully understand the natural history of COVID-19 and the evidence on COVID-19-related PD is scant. Though the possibilities presented are speculative, they are theory-based, and supported by prior evidence from other neurotrophic viruses closely related to SARS-CoV-2. Neurologists should be on high alert and vigilant for potential acute and chronic complications when encountering PD patients who are suspected of having COVID-19.

4.
Sci Rep ; 10(1): 5788, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32238886

RESUMO

This study was performed to investigate the effect of the chloroform fraction from Actinidia arguta (CFAA) on cognitive dysfunction in a C57BL/6 mouse model fed a high-fat diet (HFD) for 12 weeks. The CFAA has the protective effect on high glucose-induced neurotoxicity in MC-IXC cell (neuroblastoma cell line). In a C57BL/6 mouse model fed a HFD for 12 weeks, the improved glucose tolerance and cognitive dysfunction were observed in a group ingesting CFAA. In the brain tissue analysis, the impaired cholinergic, antioxidant system and mitochondria functions were improved in the CFAA group. In addition, in a molecular biology study, it was observed that CFAA improves HFD-induced abnormal insulin signaling such as increase of IRS phosphorylation at serine residues and reduction of Akt phosphorylation caused by the increase of JNK phosphorylation and then inhibited apoptosis. In the UPLC Q-TOF/MS analysis, pentacyclic triterpenoids such as asiatic acid (AA), madecassic acid (MA) were identified in CFAA as main compounds. Therefore, these results propose that Actinidia arguta rich in pentacyclic triterpenoids may be effective as preventive matter a therapeutic strategy to improve neurodegenerative disease caused by HFD.

5.
Am J Sports Med ; 48(6): 1374-1378, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32255666

RESUMO

BACKGROUND: Factors associated with graft survival after lateral meniscal allograft transplantation (MAT) have not been fully determined, and survival analysis focused on effect of varus alignment has not been performed. HYPOTHESIS: Varus alignment of the knee leads to better graft survival and clinical outcomes after lateral MAT than normal alignment. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: The records of 204 consecutive patients who underwent lateral MAT were reviewed. After exclusion of cases undergoing revision MAT, cases without hip-knee-ankle standing radiographs, and cases with valgus alignment, the patients were categorized into 2 groups, those with normal alignment within -3° to 3° of the mechanical axis and those with varus alignment >3°. Cumulative graft survival rates were compared in the 2 groups before and after controlling for other covariates, including sex, age, body mass index (BMI), time from meniscectomy, the number of accompanying procedures, and cartilage status. Failure was defined as (1) a graft tear involving >50% or unstable peripheral rim of the allograft; (2) a Lysholm score <65 that was not improved afterward; (3) meniscectomy >50% or to the zone of meniscocapsular junction; or (4) conversion to revision MAT, realignment osteotomy, or arthroplasty. Clinical outcomes were compared between the 2 groups by Lysholm score. RESULTS: Of the 190 patients, 149 showed normal alignment of 0.3° ± 1.3° (range, -3° to 3°) and 41 showed varus alignment of 4.8° ± 0.6° (range, 4°-8°). A total of 22 patients (11.6%) experienced MAT failure: 21 patients with normal alignment and 1 with varus alignment. Kaplan-Meier survival analysis showed a significant difference in the cumulative graft survival rates between the 2 groups (log-rank test, P = .001). After controlling for age, sex, BMI, time from meniscectomy, the number of accompanying procedures, and cartilage status, varus alignment was found to be a significant protective factor (P = .004). On the other hand, there was no difference in clinical improvement measured by the Lysholm score between the 2 groups (P = .651). CONCLUSION: Varus alignment was associated with better graft survival after lateral MAT than normal alignment. However, no significant differences in clinical outcomes were observed.

6.
Nutrients ; 12(3)2020 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-32245029

RESUMO

To evaluate possibility as a skin whitening agent of Sorghum bicolor (S. bicolor), its antioxidant activity and anti-melanogenic effect on 3-isobutyl-1-methylxanthine (IBMX)-induced melanogenesis in B16/F10 melanoma cells were investigated. The result of total phenolic contents (TPC) indicated that 60% ethanol extract of S. bicolor (ESB) has the highest contents than other ethanol extracts. Antioxidant activity was evaluated using the 2,2'-azino-bis-(3-ethylbenzothiazolin-6-sulfonic acid) diammonium salt (ABTS)/1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical scavenging activities and malondialdehyde (MDA) inhibitory effect. These results showed ESB has significant antioxidant activities. Inhibitory effect against tyrosinase was also assessed using L-tyrosine (IC50 value = 89.25 µg/mL) and 3,4-dihydroxy-L-phenylalanine (L-DOPA) as substrates. In addition, ESB treatment effectively inhibited melanin production in IBMX-induced B16/F10 melanoma cells. To confirm the mechanism on anti-melanogenic effect of ESB, we examined melanogenesis-related proteins. ESB downregulated melanogenesis by decreasing expression of microphthalmia-associated transcription factor (MITF), tyrosinase and tyrosinase-related protein (TRP)-1. Finally, 9-hydroxyoctadecadienoic acid (9-HODE), 1,3-O-dicaffeoylglycerol and tricin as the main compounds of ESB were analyzed using the ultra-performance liquid chromatography-ion mobility separation-quadrupole time of flight/tandem mass spectrometry (UPLC-IMS-QTOF/MS2). These findings suggest that ESB may have physiological potential to be used skin whitening material.

7.
Anal Chim Acta ; 1107: 30-39, 2020 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-32200899

RESUMO

A periodic nano-porous surface on quartz crystal electrodes was carefully fabricated for increasing the mass-sensitive areas. Detailed porous structures were prepared by analyzing Au electrochemical reduction process of PS layer coated quartz crystals. The sensitivity measurement of the porous quartz crystals was performed with several traditional methods, and an optimized reduction time for higher sensitivity was determined. The frequency shift of the nano-porous quartz crystals showed 10 times bigger change with the same concentration of target solutions in self-assembly procedures. In the procedures, the freshly increased surface portion did not produce additional molecular slip-effects on the measured resonant resistance values, thus, the periodic porous chips showed another side merit for the mass sensor applications. We propose a possible use of the current porous surface as a platform for developing other high-performance sensors and analyses.

8.
Artigo em Inglês | MEDLINE | ID: mdl-32067077

RESUMO

PURPOSE: To perform a radiographic assessment of osteoarthritis, progression after partial meniscectomy (PM) in degenerative medial meniscus posterior root tears (MMPRTs) in relation to preoperative mechanical axis (MA). The hypothesis is that neutral-aligned knees with degenerative MMPRTs have better radiographic outcomes than those of varus-aligned knees after arthroscopic PM. METHODS: Records of 114 patients with degenerative MMPRTs and Kellgren-Lawrence (KL) grade ≤ 2 osteoarthritis, who underwent PM, had preoperative weight-bearing hip-to-ankle radiographs from 2004 to 2014, and were followed-up for at least 5 years were reviewed retrospectively. The mean follow-up period was 8.3 ± 2.8 years. Preoperative MA values were used to classify the patients into either a Neutral (N valgus 3° to varus 3°; n = 60) or Varus-aligned group (V varus > 3°; n = 54). Joint space width (JSW; mm) and KL grade (0/1/2/3/4) were measured preoperatively and finally on weight-bearing 45° flexion posteroanterior and anteroposterior radiographs, respectively. RESULTS: Preoperative JSW and KL grade did not differ significantly between the groups (N vs V; JSW 3.64 ± 0.83 vs 3.44 ± 0.81, P = 0.201; KL grade, 2/31/27/0/0 vs 0/22/32/0/0, P = 0.162); however, the final JSW and KL grade differed significantly between the groups (N vs V; JSW 3.03 ± 0.78 vs 2.07 ± 0.87; KL grade, 0/21/23/13/3 vs 0/10/26/21/6, both P < 0.001). The N group showed significantly less KL progression compared with the V group (N vs V; progression/no progression, 27/33 vs 42/12, P = 0.001). CONCLUSION: The progression of radiographic osteoarthritis after PM for degenerative MMPRTs was greater in varus-aligned knees than in neutral-aligned knees. PM should be considered cautiously in patients with varus-aligned knees. LEVEL OF EVIDENCE: Retrospective comparative study, Level III.

9.
Mov Disord ; 35(5): 868-876, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32039503

RESUMO

BACKGROUND: SNCA multiplication is a genomic cause of familial PD, showing dosage-dependent toxicity. Until now, nonallelic homologous recombination was suggested as the mechanism of SNCA duplication, based on various types of repetitive elements found in the spanning region of the breakpoints. However, the sequence at the breakpoint was analyzed only for 1 case. OBJECTIVES: We have analyzed the breakpoint sequences of 6 patients with PD who had duplicated SNCA using whole-genome sequencing data to elucidate the mechanism of SNCA duplication. METHODS: Six patient samples with SNCA duplication underwent whole-genome sequencing. The duplicated regions were defined with nucleotide-resolution breakpoints, which were confirmed by junction polymerase chain reaction and Sanger sequencing. The search for potential non-B DNA-forming sequences and stem-loop structure predictions was conducted. RESULTS: Duplicated regions ranged from the smallest region of 718.3 kb to the largest one of 4,162 kb. Repetitive elements were found at 8 of the 12 breakpoint sequences on each side of the junction, but none of the pairs shared overt homologies. Five of these six junctions had microhomologies (2-4 bp) at the breakpoint, and a short stretch of sequences was inserted in 3 cases. All except one junction were located within or next to stem-loop structures. CONCLUSION: Our study has determined that homologous recombination mechanisms involving repetitive elements are not the main cause of the duplication of SNCA. The presence of microhomology at the junctions and their position within stem-loop structures suggest that replication-based rearrangements may be a common mechanism for SNCA amplification. © 2020 International Parkinson and Movement Disorder Society.

10.
J Neurol ; 267(6): 1672-1678, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32067125

RESUMO

Evolution of vestibular function requires further elucidation in spinocerebellar ataxia (SCA). This study aimed to determine temporal evolution in the findings of head impulse tests (HITs) in SCA type 6 (SCA6). We serially evaluated HITs in 12 patients with SCA6 using video-oculography for 3 months to 5 years [median = 12 months, interquartile range (IQR) = 9-50] at two university hospitals in South Korea. Patients (8/12, 67%) usually showed abnormal responses at least for one semicircular canal during video-HITs. The gains of the vestibulo-ocular reflex (VOR) for the anterior canals (ACs) were larger than those for the posterior canals (PCs, p = 0.005) at initial presentation. During the follow-up, the VOR gains decreased for the horizontal canals (HCs, p = 0.008) and ACs (p = 0.021), but those for the PCs remained unchanged (p = 0.212). Perverted HITs were observed in seven patients (7/12, 58%). The differences in the head impulse VOR gains were larger between the ACs and PCs (ΔACs - PCs) in those with perverted HITs than in those without (p = 0.003). The gains for each semicircular canal showed a negative correlation with the Scale for the Assessment and Rating of Ataxia (HCs, Spearman's coefficient = - 0.675, p = 0.003; ACs, - 0.637, p = 0.006; PCs, - 0.605, p = 0.010). The head impulse gain of the VOR may serve a marker for clinical decline in SCA6. The dissociation in the temporal evolution of the VOR gain indicates dissimilar cerebellar modulation of the vestibular signals from each semicircular canal.

11.
Small ; 16(4): e1906458, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31894633

RESUMO

Battery-type materials are promising candidates for achieving high specific capacity for supercapacitors. However, their slow reaction kinetics hinders the improvement in electrochemical performance. Herein, a hybrid structure of P-doped Co3 O4 (P-Co3 O4 ) ultrafine nanoparticles in situ encapsulated into P, N co-doped carbon (P, N-C) nanowires by a pyrolysis-oxidation-phosphorization of 1D metal-organic frameworks derived from Co-layered double hydroxide as self-template and reactant is reported. This hybrid structure prevents active material agglomeration and maintains a 1D oriented arrangement, which exhibits a large accessible surface area and hierarchically porous feature, enabling sufficient permeation and transfer of electrolyte ions. Theoretical calculations demonstrate that the P dopants in P-Co3 O4 @P, N-C could reduce the adsorption energy of OH- and regulate the electrical properties. Accordingly, the P-Co3 O4 @P, N-C delivers a high specific capacity of 669 mC cm-2 at 1 mA cm-2 and an ultralong cycle life with only 4.8% loss over 5000 cycles at 30 mA cm-2 . During the fabrication of P-Co3 O4 @P, N-C, Co@P, N-C is simultaneously developed, which can be integrated with P-Co3 O4 @P, N-C for the assembly of asymmetric supercapacitors. These devices achieve a high energy density of 47.6 W h kg-1 at 750 W kg-1 and impressive flexibility, exhibiting a great potential in practical applications.

12.
Biol Blood Marrow Transplant ; 26(5): 965-971, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31962166

RESUMO

Although long-term antiviral prophylaxis is recommended to prevent varicella zoster virus (VZV) infection in seropositive recipients of allogeneic and autologous (auto-) hematopoietic cell transplantation (HCT), studies of VZV infections in pediatric auto-HCT recipients are rare. This study aimed to investigate the incidence and characteristics of VZV infection in pediatric auto-HCT recipients and explore the risk factors of VZV infection and its effect on survival outcomes. This study included all pediatric patients who underwent auto-HCT at Samsung Medical Center, Seoul, Korea, between January 1998 and December 2013. Before 2006, short-term acyclovir prophylaxis was provided until neutrophil engraftment; thereafter, routine prophylaxis was not provided. Patients who developed either herpes zoster or chickenpox within 2 years from transplantation were identified, and a chart review was performed. A total of 413 recipients and 698 auto-HCTs were included. Sixty-one episodes of VZV infections were identified in 54 patients. Fourteen cases of VZV infection (23%; 14 of 61) occurred within 30 days after auto-HCT. The cumulative incidence of the first episode of VZV infection at 2 years after transplantation was 14% (95% confidence interval [CI], 7.9% to 22.8%) in all recipients and 9% (95% CI, 1.0 to 26.6) in VZV-seronegative patients. Notably, the VZV infection rate increased with age and the VZV infection rate in patients age 15 to 19 years was almost three times higher than in patients age 0 to 4 years (28% versus 10%; P = .003). However, there was no difference in the VZV infection rate between recipients of single auto-HCT and recipients of tandem auto-HCT. Two patients died of disseminated VZV infection. VZV infection is a considerable risk in auto-HCT recipients with or without short-term prophylaxis. Universal antiviral prophylaxis might be considered, particularly in older children, regardless of VZV serologic results. To our knowledge, this is the largest study of VZV infection in pediatric auto-HCT recipients reported to date.

13.
Arthroscopy ; 36(2): 524-532, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31901388

RESUMO

PURPOSE: To compare the serial changes in radiographic outcomes in terms of the mechanical axis (MA) angle and medial joint space width (JSW) between medial meniscus posterior root tear (MM PRT) and non-root tear (MM NRT) after arthroscopic partial meniscectomy (APM). METHODS: Patients who underwent APM for degenerative MM PRT or MM NRT from January 1999 to July 2012 were retrospectively reviewed. One hundred ten patients each in the MM PRT group and the MM NRT group, who were matched through propensity score matching (adjusting for confounding factors such as age, sex, body mass index, anatomic axis, cartilage state of the medial compartment, and follow-up period), were included in the study. The MA angle on weightbearing whole-leg radiographs and the medial JSW on weightbearing 45° flexion posteroanterior radiographs were measured to evaluate the radiographic outcomes. The serial changes were compared between radiographs taken before surgery, at postoperative 3 to 5 years, and at postoperative 5 years to the last follow-up. The linear mixed model was used to compare the changes in radiographic outcomes during the follow-up period between groups. RESULTS: The 2 groups were balanced with standardized mean differences of <0.2 after propensity score matching. Both the MM PRT and NRT groups showed increased varus alignment after surgery. However, there was no significant difference in the change in the MA angle during the follow-up period between groups (P = .182). The medial JSW also showed progression of joint space narrowing after surgery in both groups; however, there was no significant difference in the change in medial JSW during the follow-up period between groups (P = .270). CONCLUSION: The radiographic outcomes after partial meniscectomy in terms of the MA angle and medial JSW show comparable results between degenerative MM PRT and NRT after proper matching of confounding factors. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

14.
Orthop Traumatol Surg Res ; 106(3): 435-442, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31924547

RESUMO

BACKGROUND: Femoral coronal bowing (FCB) has been reported to be a risk factor for mechanical malalignment after total knee arthroplasty (TKA). However, the effects of FCB on the long-term survivorship (when postoperative mechanical alignment (MA) is neutral after TKA) have not been determined. HYPOTHESIS: The effects of FCB on the cumulative survivorship after TKA may be significantly smaller compared with those of MA. PATIENTS AND METHODS: Consecutive 328 knees of 211 patients (10 males, 201 females) who underwent TKA between 1995 and 2009 (mean age of 64.2±6.7 years at the time of TKA, mean follow-up period of 11.9±2.5 years) were retrospectively evaluated. FCB and MA were evaluated using preoperative and immediate postoperative whole-leg anteroposterior radiographs, respectively. The patients were grouped according to FCB and postoperative MA, which included group A (FCB≤5°, MA≤3°), B (FCB>5°, MA≤3°), C (FCB>5°, MA>3°), and D (FCB≤5°, MA>3°). Primary end-point was defined as aseptic mechanical failures requiring revision TKA. Survivorship was assessed using the Kaplan-Meier method and compared using log-rank tests. Factors associated with the risk of aseptic mechanical failures were analyzed by Cox regression analysis. Preoperative and final follow-up clinical outcomes were assessed using Hospital for Special Surgery (HSS) scores. RESULTS: Group A, B, C, and D included 190, 73, 40, and 25 knees, respectively. The 10-year survivorship was similar between group A and B (96.3±1.4% vs. 98.6±1.4%; p=0.733) and group C and D (87.3±5.3 vs. 87.6±6.7%; p=0.974); however, it was significantly higher in group B than in group C (p=0.036) and in group A than in group D (p=0.005). Age (OR=0.991; 95% CI 0.906-1.085; p=0.002) and MA>3° (OR=3.645; 95% CI 1.744-7.604; p=0.001) were associated with the risk of aseptic mechanical failures. The mean preoperative and final HSS scores in the four groups were not significantly different. DISCUSSION: Marked FCB was not associated with long-term survivorship for knees with neutral alignment after TKA. However, non-neutral postoperative alignment reduced long-term survivorship for knees with marked FCB. LEVEL OF EVIDENCE: III, Retrospective comparative cohort study.

15.
Xenotransplantation ; 27(1): e12559, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31566261

RESUMO

BACKGROUND: We aimed to investigate (a) the long-term survival of corneal grafts from α1,3-galactosyltransferase gene-knockout miniature (GTKOm) pigs in non-human primates as a primary outcome and (b) the effect of anti-CD20 antibody on the survival of corneal grafts from GTKOm pigs as a secondary outcome. METHODS: Nine rhesus macaques undergoing full-thickness corneal xenotransplantation using GTKOm pigs were systemically administered steroid, basiliximab, intravenous immunoglobulin, and tacrolimus with (CD20 group) or without (control group) anti-CD20 antibody. RESULTS: Graft survival was significantly longer (P = .008) in the CD20 group (>375, >187, >187, >83 days) than control group (165, 91, 72, 55, 37 days). When we compared the graft survival time between older (>7- month-old) and younger (≤7-month-old) aged donor recipients, there was no significant difference. Activated B cells were lower in the CD20 group than control group (P = .026). Aqueous humor complement C3a was increased in the control group at last examination (P = .043) and was higher than that in the CD20 group (P = .014). Anti-αGal IgG/M levels were unchanged in both groups. At last examination, anti-non-Gal IgG was increased in the control group alone (P = .013). CONCLUSIONS: The GTKOm pig corneal graft achieved long-term survival when combined with anti-CD20 antibody treatment. Inhibition of activated B cells and complement is imperative even when using GTKO pig corneas.

16.
Xenotransplantation ; 27(2): e12562, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31642566

RESUMO

BACKGROUND: Xenogeneic islet transplantation using porcine pancreata has been a promising option for substituting human islet transplantation. Moreover, recent advances in pre-clinical results have put islet xenotransplantation closer to the possibility of clinical application. While preparing for the era of clinical xenotransplantation, developing non-invasive immune monitoring method which could predict the graft fate could benefit the patient. However, there are few reports showing predictive immune parameters associated with the fate of the graft in islet xenotransplantation. METHODS: The absolute number and ratio of T-cell subsets have been measured via flow cytometry from the peripheral blood of 16 rhesus monkeys before and after porcine islet xenotransplantation. The correlation between the graft survival and the absolute number or ratio of T cells was retrospectively analyzed. RESULTS: The ratio of CD4+ versus CD8+ T cells was significantly reduced due to CD8+ effector memory cells' increase. Correlation analyses revealed that CD4+ /CD8+ , CD4+ /CD8+ naïve, CD4+ naïve/CD8+ naïve, and CD4+ central memory/CD8+ naïve cell ratios negatively correlated with the duration of graft survival. Conversely, further analyses discovered strong, positive correlation of CD4+ /CD8+ cell ratios within the early graft-rejected monkeys (≤60 days). CONCLUSIONS: This retrospective study demonstrated that CD4+ /CD8+ ratios correlated with graft survival, especially in recipients which rejected the graft in early post-transplantation periods. CD4+ /CD8+ ratios could be used as a surrogate marker to predict the graft fate in pig-to-NHP islet xenotransplantation.

17.
J Med Primatol ; 49(1): 44-46, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31657019

RESUMO

Ectopic ureter is a congenital abnormality where the ureter terminates at a site other than the urinary bladder. A five-year-old female rhesus monkey presented with a urine odor, a wet perineum, and persistent dribbling of urine. An ultrasound examination revealed a cyst-like structure (1 × 0.75 cm) on the left side of the bladder. Computed tomographic excretory urography (CTEU) imaging revealed a left unilateral extramural ectopic ureter, which was connected to the vagina. The perineum and wet hair were dried and disinfected with 0.4% chlorhexidine for perineal hygiene and skin care. The animal was closely monitored for potential moist dermatitis near the perineum and for urinary tract infection. The complete blood count (CBC) and blood chemistry results showed no signs of inflammation during the observation period. This is the first report of detailed diagnosis of ectopic ureter by ultrasound and CTEU in a female rhesus monkey.

18.
Am J Sports Med ; 48(2): 326-333, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31825644

RESUMO

BACKGROUND: Long-term outcomes after lateral meniscal allograft transplantation (MAT) are not completely understood. PURPOSE/HYPOTHESIS: We investigated changes in meniscal extrusion in the coronal and sagittal planes using magnetic resonance imaging (MRI) after lateral MAT through long-term follow-up. We hypothesized that meniscal extrusion would progress during follow-up. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Patients subjected to lateral MAT were followed up by MRI evaluation in both planes at 1, 4 to 6, and >8 years after MAT. Meniscal extrusion and entire meniscal widths in the coronal plane and anterior (ACMD) and posterior (PCMD) cartilage meniscal distances in the sagittal plane were measured, and values were compared at each time point. Clinical outcomes were evaluated using the Lysholm score. RESULTS: A total of 27 lateral MATs were included with a mean MRI follow-up period of 10.3 years (range, 8.1-15.3 years). The mean absolute meniscal extrusion (coronal plane) was not significantly different at each time point. However, the relative value differed (0.27 ± 0.04 at 1 year; 0.33 ± 0.06 at >8 years after MAT) owing to entire meniscal width reduction. There was no difference in the mean absolute value of the ACMD in the sagittal plane. However, relative values differed (0.21 ± 0.01 at 1 year; 0.27 ± 0.06 at >8 years) owing to entire meniscal width reduction. Absolute and relative values of the PCMD remained unaffected at each time point. The Lysholm score increased after surgery but did not differ postoperatively. CONCLUSION: During the long-term follow-up of extrusion after lateral MAT using MRI, absolute extrusion remained unchanged across all planes. Relative extrusion in the coronal plane and of the ACMD in the sagittal plane significantly increased, with no differences in the PCMD on follow-up. Clinical outcomes after surgery improved compared with those before surgery and were maintained throughout the long-term follow-up period.

19.
Arch Orthop Trauma Surg ; 140(3): 391-400, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31845061

RESUMO

INTRODUCTION: In total knee arthroplasty (TKA) using the intramedullary tibial cutting guide (IMTCG), the positioning of the IMTCG is important for accurate tibial bone resection. The aim of this study was to evaluate the ideal entry point of IMTCG and affecting radiologic factors. MATERIALS AND METHODS: From May 2017 to February 2018, 91 consecutive TKAs for osteoarthritis were included. From preoperative full-length radiographs, we measured the medial proximal tibia angle (MPTA), lateral distal tibia angle (LDTA), tibial bowing angle (TBA), medial to lateral width of the tibial plateau, tibial length, and ideal coronal entry point. In preoperative short knee lateral radiographs, we measured the anterior to posterior length of the tibial plateau, tibial posterior slope angle (TPSA), metaphysio-diaphyseal angle (MDA), and ideal sagittal entry point. The ideal coronal and sagittal entry points were defined as the points crossing the tibial plateau and tibial anatomical axis on the coronal and sagittal radiographs, respectively. RESULTS: The ideal entry point was 51.4 ± 4.3% (SD) from the medial margin and 27.0 ± 5.8% (SD) from the anterior margin of the tibial plateau. However, the range varied from 39.8 to 60.5% on the coronal plane and from 9.6 to 37.7% on the sagittal plane, respectively. As the MPTA (rho = - 0.490) and TBA (rho = - 0.433) were increased, the coronal entry point moved medially. As TPSA (rho = - 0.761) and MDA (rho = - 0.495) were increased, the sagittal entry point moved anteriorly. CONCLUSIONS: The ideal entry point of IMTCG should vary according to the individual tibial morphology.

20.
Orthop Traumatol Surg Res ; 106(3): 487-493, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31859252

RESUMO

BACKGROUND: Knee malalignment is strongly associated with risk of knee osteoarthritis (OA). Although several studies have described the relationship between valgus knee alignment and incidence of severe lateral OA, little research is available on the association with non-valgus (neutral or varus) knee alignment. Therefore, we performed a retrospective study to determine: 1) whether a substantial proportion of severe lateral OA patients have non-valgus knee alignment and 2) whether there are any difference in clinical manifestations between patients with valgus and non-valgus alignment. HYPOTHESIS: A large proportion of severe lateral OA patients in Korea have non-valgus knee alignment. PATIENTS AND METHODS: The medical records of 647 patients (825 knees) who visited our outpatient clinic from 2008 to 2018 and were diagnosed with lateral OA were retrospectively reviewed. Knee OA severity was evaluated according to the Kellgren-Lawrence (K-L) grading system and those with K-L grade 3 or 4 were enrolled in this study. Alignment was measured by the hip-knee-ankle angle on full-limb radiographs and classified as varus (<180°), neutral (180°), or valgus (>180°). Patients with K-L grade 4 lateral OA (bone-on-bone arthritis) were divided into two groups according to knee alignment (non-valgus or valgus) and compared for recommended treatment (surgery or conservative treatment) as an indicator of clinical manifestations. RESULTS: Of the 825 knees, 67.1% (553/825) were K-L grade 3 or 4. Of these 553 K-L grade 3/4 knees, 20.4% (113/553) had neutral, 23.3% (129/553) varus, and 56.2% (331/553) valgus knee alignment. Notably, 43.8% (242/553) of the K-L grade 3 or 4 knees had non-valgus alignment (95% CI: 40%-48%, exact binomial test). Of the K-L grade 4 patients (263 knees), the proportion recommended conservative treatment was significantly higher in the non-valgus group (80.2% (69/86)) than the valgus group (62.1% (110/177)) (χ2 test, p=0.003)). CONCLUSION: In contrast to the widespread belief that most lateral OA patients have valgus knee alignment, a substantial proportion of Korean patients with severe lateral OA in this study had non-valgus alignment. In addition, these non-valgus alignment patients presented with significantly milder clinical manifestations in bone-on-bone lateral OA than valgus patients. While orthopaedic surgeons tend to initially consider surgery for bone-on-bone lateral OA, full-limb radiographs should be acquired to assess knee alignment, because patients with non-valgus alignment may be treated conservatively. LEVEL OF EVIDENCE: III, Case control study.

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