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2.
J Vasc Surg ; 2020 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-32645420

RESUMO

OBJECTIVE: Vascular graft and endograft infection (VGEI) has high morbidity and mortality rates. Diagnosis is complicated since symptoms vary and can be non-specific. A recent meta-analysis identified the use of 18F-fluoro-D-deoxyglucose positron emission tomography-computed tomography (18F-FDG PET(/CT)) as the most valuable tool for diagnosing VGEI and favorable to computed tomography as the current standard. However, the availability and varied use of several interpretation methods, without consensus on which interpretation method is best, complicates clinical use. The aim of this study was to evaluate the diagnostic performance of different interpretation methods of 18F-FDG PET(/CT) in diagnosing VGEI. METHODS: A systematic review was performed according to the PRISMA guidelines. Data sources included PubMed/Medline, Embase, and Cochrane. A meta-analysis was conducted on the different interpretation methods for 18F-FDG PET(/CT) in diagnosing VGEI, including visual FDG uptake intensity, visual FDG uptake pattern, and quantitative SUVmax. RESULTS: Out of 613 articles, 13 were included-10 prospective and 3 retrospective articles. The FDG uptake pattern method (I2 26.2%) showed negligible heterogeneity, while the FDG uptake intensity (I2 42.2%) and SUVmax (I2 42.1%) methods both showed moderate heterogeneity. The pooled sensitivity for FDG uptake intensity was 0.90 (95% CI: 0.79-0.96), for uptake pattern 0.94 (95% CI: 0.89-0.97), and for the SUVmax method 0.95 (95% CI: 0.76-0.99). The pooled specificity for FDG uptake intensity was 0.59 (95% CI: 0.38-0.78), whereas for FDG uptake pattern it was 0.81 (95% CI: 0.71-0.88) and for SUVmax it was 0.77 (95% CI: 0.63-0.87). The uptake pattern interpretation method demonstrated the best positive and negative post-test probability-82% and 10%, respectively. CONCLUSION: This meta-analysis identified the FDG uptake pattern as the most accurate assessment method of 18F-FDG PET(/CT) for diagnosing VGEI. The optimal SUVmax cutoff, depending on the vendor, demonstrated strong sensitivity and moderate specificity.

3.
Sci Rep ; 10(1): 12568, 2020 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-32724093

RESUMO

Calcium fluorometry is critical to determine cell homeostasis or to reveal communication patterns in neuronal networks. Recently, characterizing calcium signalling in neurons related to interactions with nanomaterials has become of interest due to its therapeutic potential. However, imaging of neuronal cell activity under stable physiological conditions can be either very expensive or limited in its long-term capability. Here, we present a low-cost, portable imaging system for long-term, fast-scale calcium fluorometry in neurons. Using the imaging system, we revealed temperature-dependent changes in long-term calcium signalling in kidney cells and primary cortical neurons. Furthermore, we introduce fast-scale monitoring of synchronous calcium activity in neuronal cultures in response to nanomaterials. Through graph network analysis, we found that calcium dynamics in neurons are temperature-dependent when exposed to chitosan-coated nanoparticles. These results give new insights into nanomaterial-interaction in living cultures and tissues based on calcium fluorometry and graph network analysis.

4.
Artigo em Inglês | MEDLINE | ID: mdl-32616305

RESUMO

The effectiveness of postoperative radiotherapy (PORT) in improving outcomes remains debatable for oral squamous cell carcinoma (OSCC) patients with pathological intermediate-risk factors (IRFs) after surgery. A retrospective analysis was conducted on 432 intermediate-risk OSCC patients defined by histological reporting of close margin (<5mm), early nodal disease (pN1), depth of invasion/tumour thickness ≥5mm, perineural invasion, and/or lymphovascular invasion. Outcomes measured were disease-free survival (DFS), disease-specific survival (DSS), and overall survival (OS). PORT was associated with an improvement in 5-year DFS on univariable analysis (80% vs 71%; P=0.044), but this did not remain significant on multivariable analysis. PORT was not associated with differences in DSS or OS. The surgical salvage rate was similar in the PORT and surgery-only groups (41% vs 47%; P=0.972). Perineural invasion was found to be an independent predictor of inferior DSS (hazard ratio (HR) 2.19), DFS (HR 1.89), and OS (HR 1.97). Significantly worse outcomes were observed for patients with ≥4 concurrent IRFs. The application of PORT was associated with lower rates of recurrence, but the benefit was less apparent on mortality. Patients with perineural invasion and multiple concurrent IRFs were found to be at greatest risk, representing a subset of intermediate-risk OSCC patients who may benefit from PORT.

5.
Anesthesiology ; 133(2): 251-254, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32667153
7.
Artigo em Inglês | MEDLINE | ID: mdl-32501855

RESUMO

BACKGROUND: Acute colonic pseudo-obstruction (Ogilvie syndrome [OS]) is a rare but devastating condition that can develop in orthopaedic patients postoperatively. The objective of this study was to identify the risk factors for developing OS after total hip arthroplasty (THA) or total knee arthroplasty (TKA) and to compare the outcomes between patients who did and did not develop OS postoperatively. METHODS: This was a retrospective review using the National Inpatient Sample, a national database incorporating inpatient hospitalization information. ICD-9 codes were used to identify patients who underwent primary and revision THA or TKA. Patients were separated based on the diagnosis of OS. Primary outcomes assessed included patient mortality, postoperative complications, length of stay, and cost during index hospitalization. RESULTS: From 2001 to 2014, a total of 12,541,169 patients underwent primary and revision THA or TKA. Of those, 3,182 patients (0.03%) developed OS postoperatively. There was an increased incidence of OS in revision THA and TKA compared with primary THA and TKA. Fluid and electrolyte disorders were associated with the largest increased adjusted risk of OS. Patients with OS had an increased adjusted risk of overall postoperative complications and being discharged to skilled nursing facility. Patients with OS had an increased average length of stay and hospitalization cost compared with patients without OS. DISCUSSION: Given our findings, the risk factors for the development of OS, including revision surgery, should be identified and minimized during the perioperative period to prevent the development of this morbid and potentially life-threatening complication. LEVEL OF EVIDENCE: III (Retrospective cohort study).

8.
Pestic Biochem Physiol ; 167: 104596, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32527442

RESUMO

Pretreatment with sublethal concentrations (LC10) of three insecticides (chlorfenapyr, dinotefuran, and spinosad) enhanced tolerance to a lethal dose of the respective insecticide in the Western flower thrips, Frankliniella occidentalis. To identify genes responding to sublethal treatment with insecticides, transcriptome analysis was conducted for thrips treated with LC10 of the three insecticides. When based on a fold change >1.5 or < -1.5 as a selection criterion, 199 transcripts were commonly up-regulated, whereas 31 transcripts were commonly down-regulated following all three insecticide treatments. The differential expression levels of representative genes were validated by quantitative PCR. Most over-transcribed transcripts could be categorized as basic biological processes, such as proteolysis and lipid metabolism. Detoxification genes, such as one glutathione S transferase S1, three UDP-glucuronosyltransferases, four CYP450s, and one ABC transporter G family member 20, were commonly overexpressed in all three insecticide-treated groups. Knockdown of the five representative commonly overexpressed genes via ingestion RNA interference increased mortalities to all the three test insecticides, supporting their common role in tolerance induction. In contrast, three C2H2-type zinc finger-containing proteins were significantly down-regulated in all insecticide-treated thrip groups. Since the tested insecticides have distinct structures and modes of action, the roles of commonly expressed genes in tolerance were discussed.


Assuntos
Inseticidas , Tisanópteros , Animais , Flores , Interferência de RNA , Transcriptoma
9.
World J Surg ; 2020 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-32494998

RESUMO

BACKGROUND: Frailty in the vascular surgical ward is common and predicts poor surgical outcomes. The aim of this study was to analyze transitions in frailty state in elderly patients after vascular surgery and to evaluate influence of patient characteristics on this transition. METHODS: Between 2014 and 2018, 310 patients, ≥65 years and scheduled for elective vascular surgery, were included in this cohort study. Transition in frailty state between preoperative and follow-up measurement was determined using the Groningen Frailty Indicator (GFI), a validated tool to measure frailty in vascular surgery patients. Frailty is defined as a GFI score ≥4. Patient characteristics leading to a transition in frailty state were analyzed using multivariable Cox regression analysis. RESULTS: Mean age was 72.7 ± 5.2 years, and 74.5% were male. Mean follow-up time was 22.7 ± 9.5 months. At baseline measurement, 79 patients (25.5%) were considered frail. In total, 64 non-frail patients (20.6%) shifted to frail and 29 frail patients (9.4%) to non-frail. Frail patients with a high Charlson Comorbidity Index (HR = 0.329 (CI: 0.133-0.812), p = 0.016) and that underwent a major vascular intervention (HR = 0.365 (CI: 0.154-0.865), p = 0.022) had a significantly higher risk to remain frail after the intervention. CONCLUSIONS: The results of this study, showing that after vascular surgery almost 21% of the non-frail patients become frail, may lead to a more effective shared decision-making process when considering treatment options, by providing more insight in the postoperative frailty course of patients.

10.
Anesthesiology ; 133(1): 13-15, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32550679
11.
J Endovasc Ther ; : 1526602820936185, 2020 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-32567964

RESUMO

Purpose: To compare the impact of 2 commercially available custom-made fenestrated endografts on patient anatomy. Materials and Methods: The records of 234 patients who underwent fenestrated endovascular aneurysm repair for abdominal aortic aneurysm from March 2002 to July 2016 in 2 hospitals were screened to identify those who had pre- and postoperative computed tomography angiography assessments with a slice thickness of ≤2 mm. The search identified 145 patients for further analysis: 110 patients (mean age 72.4±7.1 years; 94 men) who had been treated with the Zenith Fenestrated (ZF) endograft and 35 patients (mean age 72.3±7.3 years; 30 men) treated with the Fenestrated Anaconda (FA) endograft. Measurements included aortic diameters at the level of the superior mesenteric artery (SMA) and renal arteries, target vessel angles, target vessel clock positions, and the target vessel tortuosity index. Variables were tested for inter- and intraobserver agreement. Results: There was a good agreement between observers in all tested variables. The native anatomy changed in both groups after endograft implantation. In the ZF group, changes were seen in the angles of the celiac artery (p=0.012), SMA (p=0.022), left renal artery (LRA) (p<0.001), and the right renal artery (RRA) (p<0.001); the aortic diameter at the SMA level (p<0.001); and the LRA (p<0.001) and RRA (p<0.001) clock positions. In the FA group, changes were seen in the angles of the LRA (p=0.001) and RRA (p<0.001) and in the SMA tortuosity index (p=0.044). Between group differences in changes were seen for the aortic diameters at the SMA and renal artery levels (p<0.001 for both) and the LRA clock position (p=0.019). Conclusion: Both custom-made fenestrated endografts altered vascular anatomy. The data suggest a higher conformability of the Fenestrated Anaconda endograft compared with the Zenith Fenestrated.

12.
Ann Biomed Eng ; 2020 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-32399843

RESUMO

The use of helmets in equestrian sports has reduced the occurrence of traumatic brain injuries although, despite improvements to helmets, concussion remains a common injury. Currently, equestrian helmets are designed to pass certification standards involving a linear drop test to a rigid surface, while most concussions in equestrian sports result from oblique impacts to a compliant surface. The purpose of this study was to: (1) Compare the head kinematics and brain tissue response of the current equestrian helmet standard (EN1) and proposed standard EN13087-11 (EN2) to those associated with reconstructions of real-world equestrian concussion accidents. (2) Design a test protocol that would reflect the real-world conditions associated with concussion in equestrian sports. (3) To assess the protective capacity of an equestrian helmet using the flat turf and 45° turf proposed test protocols. Results for reconstructions of real-world concussions were obtained from a previous study (Clark et al. in J. Sci. Med. Sport 23:222-236, 2020). Using one jockey helmet model, impact tests were conducted according to the EN1 and EN2 protocols. Additionally, helmeted and unhelmeted tests were conducted at 5.9 and 6.0 m/s on to flat turf and 45° turf anvils for front, front-boss and rear-boss impact locations. The results demonstrated EN1 and EN2 both had higher magnitude accelerations and shorter duration impacts than reconstructed real-world concussive impacts. Impacts to turf anvils, on the other hand, produced similar head kinematics compared to the reconstructed real-world concussive impacts. Additionally, this study demonstrated that helmeted impacts significantly decreased rotational kinematics and brain tissue response below what is associated with unhelmeted impacts for oblique falls. However, the head kinematics and brain tissue response associated with these helmeted falls were consistent with concussion, suggesting that scope exists to improve the capacity of equestrian helmets to protect against concussion.

13.
Org Lett ; 22(11): 4424-4428, 2020 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-32406695

RESUMO

We report a simple reductive amination protocol to ligate two peptides, while simultaneously installing a ß-turn mimic at the ligation junction. This strategy uses commercially available materials, mild chemical conditions, and a chemoselective ligation reaction of unprotected peptide substrates accessed through standard solid phase methods. This system was implemented in a designed ß-hairpin system, and biophysical analysis demonstrates effective mimicry of the ß-turn.

14.
Brain Behav Immun ; 2020 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-32413559

RESUMO

Emerging evidence suggests that Complex Regional Pain Syndrome (CRPS) is in part a post-traumatic autoimmune disease mediated by an adaptive immune response after limb injuries. We previously observed in a murine tibial fracture model of CRPS that pain-related behaviors were dependent upon adaptive immune mechanisms including the neuropeptide-dependent production of IgM for 5 months after injury. However, the time course of induction of this immune response and the demonstration of germinal center formation in lymphoid organs has not been evaluated. Using the murine fracture model, we employed behavioral tests of nociceptive sensitization and limb dysfunction, serum passive transfer techniques, western blot analysis of IgM accumulation, fluorescence-activated cell sorting (FACS) of lymphoid tissues and immunohistochemistry to follow the temporal activation of the adaptive immune response over the first 3 weeks after fracture. We observed that: 1) IgM protein levels in the skin of the fractured mice were elevated at 3 weeks post fracture, but not at earlier time points, 2) serum from fracture mice at 3 weeks, but not 1 and 2 weeks post fracture, had pro-nociceptive effects when passively transferred to fractured muMT mice lacking B cells, 3) fracture induced popliteal lymphadenopathy occurred ipsilateral to fracture beginning at 1 week and peaking at 3 weeks post fracture, 4) a germinal center reaction was detected by FACS analysis in the popliteal lymph nodes from injured limbs by 3 weeks post fracture but not in other lymphoid tissues, 5) germinal center formation was characterized by the induction of T follicular helper cells (Tfh) and germinal center B cells in the popliteal lymph nodes of the injured but not contralateral limbs, and 6) fracture mice treated with the Tfh signaling inhibitor FK506 had impaired germinal center reactions, reduced IgM levels, reduced nociceptive sensitization, and no pronociceptive serum effects after administration to fractured muMT mice. Collectively these data demonstrate that tibia fracture induces an adaptive autoimmune response characterized by popliteal lymph node germinal center formation and Tfh cell dependent B cell activation, resulting in nociceptive sensitization within 3 weeks.

15.
Laryngoscope ; 2020 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-32364619

RESUMO

OBJECTIVES/HYPOTHESIS: Internal nasal valve compromise is a major cause of nasal obstruction, with a growing number of ways to treat this condition. In this study, we compared the effects of butterfly graft, spreader graft, and the bioabsorbable nasal implant on nasal airflow resistance. STUDY DESIGN: Cadaver study. METHODS: Computational fluid dynamics (CFD) simulations were completed from nine preoperative and postoperative cadaveric subjects. Each cadaveric head underwent placement of a bioabsorbable nasal implant (BNI) (Spirox Latera; Stryker ENT, Plymouth, MN), butterfly graft, or spreader graft. Pre- and postoperative computed tomography (CT) scans were used to generate three-dimensional models of the nasal airway used in steady-state CFD simulations of airflow and heat transfer during inspiration. RESULTS: Butterfly graft placement resulted in a mean improvement in nasal airway resistance of 24.9% (±7.3), whereas BNI placement resulted in a 6.7% (±1.2) improvement, and spreader graft placement also resulted in a consistent improvement of 2.6% (±13.5). Pressure within the main nasal cavity was consistently lower following butterfly graft placement versus a spreader graft or BNI. Butterfly and spreader graft placement also resulted in modest improvements in airflow allocation, whereas BNI demonstrated more variation (-1% to 12%). Heat flux was not significantly different; however, a small improvement in total heat flux was seen with all three interventions. CONCLUSIONS: The results of this study demonstrate reduction in nasal airway resistance in all three surgical interventions, with the butterfly graft demonstrating superiority to the other two techniques. However, these data only reflect a static environment and not dynamic changes in airflow seen during respiration. LEVEL OF EVIDENCE: NA Laryngoscope, 2020.

17.
Anesthesiology ; 132(6): 1304-1306, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32243331
18.
Nature ; 580(7801): 52-55, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32238942

RESUMO

Conservation laws are deeply related to any symmetry present in a physical system1,2. Analogously to electrons in atoms exhibiting spin symmetries3, it is possible to consider neutrons and protons in the atomic nucleus as projections of a single fermion with an isobaric spin (isospin) of t = 1/2 (ref. 4). Every nuclear state is thus characterized by a total isobaric spin T and a projection Tz-two quantities that are largely conserved in nuclear reactions and decays5,6. A mirror symmetry emerges from this isobaric-spin formalism: nuclei with exchanged numbers of neutrons and protons, known as mirror nuclei, should have an identical set of states7, including their ground state, labelled by their total angular momentum J and parity π. Here we report evidence of mirror-symmetry violation in bound nuclear ground states within the mirror partners strontium-73 and bromine-73. We find that a J π = 5/2- spin assignment is needed to explain the proton-emission pattern observed from the T = 3/2 isobaric-analogue state in rubidium-73, which is identical to the ground state of strontium-73. Therefore the ground state of strontium-73 must differ from its J π = 1/2- mirror bromine-73. This observation offers insights into charge-symmetry-breaking forces acting in atomic nuclei.

19.
Oral Oncol ; 105: 104661, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32244173

RESUMO

INTRODUCTION: Oral squamous cell carcinoma (OSCC) is the seventh most common cancer globally, and has been identified as a growing health concern. This study aims to evaluate the current literature comparing elective neck dissection to observation in the treatment of early-stage tongue SCC, focusing on nodal recurrence, overall survival, disease specific survival statistics from randomised controlled trials comparing the two interventions. METHODS: Systematic review and meta-analysis was conducted according to PRISMA guidelines. The odds ratio (OR) was used as a summary statistic. RESULTS: From 8 studies, there was a total of 372 cases of recurrence, 98 (15.1%) in END group and 274 (41.5%) in the Observation group. There was a significantly lower rate of recurrence in the END group compared to observation (OR 0.25, 95% CI 0.16-0.39, I2 = 54%, P < 0.00001). END was associated with higher overall survival rates when compared with observation (OR 1.95, 95% CI 1.40-2.73, I2 = 14%, P < 0.0001). END was also associated with higher disease-specific survival compared with observation (OR 1.88, 95% CI 1.21-2.93), I2 = 47%, P = 0.005), with no significant heterogeneity noted. CONCLUSIONS: END was associated with significantly lower recurrence rates and higher overall and disease-specific survival compared to a conservative observation approach in early-stage oral SCC with clinically N0 neck.

20.
Org Lett ; 22(9): 3734-3738, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32306737

RESUMO

A novel four-step bidirectional strategy has been used to synthesize the IJK fragment of the marine polyether natural product CTX3C from a simple monocyclic precursor in a concise and efficient manner. The four-step bidirectional sequence involves ring-closing metathesis, alcohol oxidation, enol carbonate formation, and palladium-mediated Tsuji-Trost allylation.

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