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31.

Background and objective

Persistent pain is reported in up to 34% of patients following total knee arthroplasty (TKA) for management of knee osteoarthritis (KOA). Persistent pain in this group is thought to be at least partly reflective of pain sensory hypersensitivity. The objective of this study was to evaluate sensory hypersensitivity, using mechanical and thermal quantitative sensory testing, in patients about to undergo TKA.

Design and methods

Pressure pain thresholds (PPT) and cold pain thresholds (CPT) were recorded from 30 participants prior to their TKA, and compared with recordings taken from 30 healthy control participants of similar age and gender. Thresholds were recorded locally and remotely (other knee, deltoid) to the operative knee. Group comparisons (KOA, control, groups) were made using a general linear mixed models approach with age, gender, and body mass index (BMI) included as covariates. Pairwise comparisons were conducted with Bonferonni correction for multiple comparisons.

Results

Significantly lower PPTs were at all measured sites in the KOA group compared to the control group (P < 0.001 at all sites, except the deltoid P = 0.004). Males demonstrated higher pain threshold compared to females, averaged over all sites, P = 0.02. There were no observed between-group differences in CPT (P = 0.122).

Conclusions

This study suggested that some individuals about to undergo TKA for their advanced KOA demonstrated widespread mechanical sensory hypersensitivity. These findings have potentially important clinical implications regarding perioperative and longer-term pain management in these patients.  相似文献   
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33.
BackgroundPenile prosthesis surgery has witnessed a migration from the inpatient to ambulatory surgical care setting. However, little is known about the cost savings afforded by this change in care setting and whether or not these savings come at the expense of worse perioperative outcomes.AimThe aim of this study was to identify predictors of index penile prosthesis (PP) surgery care setting, and whether ambulatory vs inpatient surgery is associated with comparable perioperative outcomes and costs.MethodsThis was a retrospective cohort study using all-payer claims data from the 2014 Healthcare Cost and Utilization Project State Databases from Florida and New York. Patient demographics, regional data, total charges (converted to costs), and 30-day revisit rates were abstracted for all patients undergoing index placement of an inflatable or malleable PP. Multivariable logistic and linear regression adjusted for facility clustering was utilized.OutcomesThe outcomes were index surgical and 30-day postoperative costs, as well as 30-day revisit rates.ResultsOf the 1,790 patients undergoing an index surgery, 394 (22.0%) received care in the inpatient setting compared to 1,396 (78.0%) in the ambulatory setting. Adjusted index procedural ($9,319.66 vs $ 10,191.35; P < .001) and 30-day acute care costs ($9,461.74 vs $10,159.42; P < .001) were lower in the ambulatory setting. The underinsured experienced lower odds of receiving surgery in the ambulatory setting (Medicaid vs private: odds ratio [OR] 0.19; 95% CI 0.06?0.55; P < .001). There was no difference in risk-adjusted odds of experiencing a 30-day revisit between patients undergoing surgery in the ambulatory vs inpatient settings (OR 1.31; 95% CI 0.78?2.21; P = .3).Clinical TranslationAmbulatory PP surgery confers significant cost savings and is associated with comparable perioperative outcomes relative to inpatient-based surgery.ConclusionsBoth clinical and nonclinical factors predict the care setting of index PP surgery. Notably, underinsured patients experienced lower odds of undergoing ambulatory surgery. Ambulatory surgery was less costly with similar 30-day revisit rates relative to inpatient-based care.Berger A, Friedlander DF, Herzog P, et al. Impact of Index Surgical Care Setting on Perioperative Outcomes and Cost Following Penile Prosthesis Surgery. J Sex Med 2019;16:1451–1458.  相似文献   
34.
BACKGROUND: A number of in vitro assays are used to determine susceptibility of HSV to antiviral agents, but results from these in vitro assays do not necessarily correlate with treatment outcome. OBJECTIVES: A method with improved capability for identifying an isolate as acyclovir (ACV) or penciclovir (PCV) resistant when resistance is borderline could greatly improve the management of HSV disease. STUDY DESIGN: A comparative evaluation of four in vitro assays, plaque reduction (PRA), DNA hybridization, plating efficiency (PEA) and plaque autoradiography (PAR) was performed to accurately identify and measure resistance of a TK-altered clinical HSV isolate (HSV-1 N4) from a patient who was non-responsive to ACV treatment. Two established criteria for the prediction of antiviral resistance, IC(50)> or =2.0 microg/ml or an IC(50) greater than 10x above a sensitive virus IC(50), as well as testing in human (MRC-5) and nonhuman (Vero and CV-1 monkey kidney) cell lines were evaluated. RESULTS: The PRA and DNA hybridization assays accurately identified HSV-1 N4 as ACV(r) in human cells when using the 10x above sensitive virus IC(50) resistance criterion. Moreover, the PEA and PAR assays failed to classify HSV-1 N4 as drug resistant and indicate that these technologies alone are inadequate for identifying resistant virus. CONCLUSIONS: The data presented herein indicate that the PRA and DNA hybridization assays most accurately identified an otherwise borderline-resistant isolate as drug resistant: (i) when a sensitive virus is used within each individual assay as a control, (ii) when ACV and PCV susceptibility is evaluated in human cells, and (iii) when the 10x above sensitive IC(50) criterion is used to classify a virus as drug-resistant. Testing of additional clinical samples is warranted to further confirm these findings.  相似文献   
35.
Influence of nanoporous alumina membranes on long-term osteoblast response   总被引:8,自引:0,他引:8  
A major goal of bone tissue engineering is to design better scaffold configuration and materials to better control osteoblast behavior. Nanoporous architecture has been shown to significantly affect cellular response. In this work, nanoporous alumina membranes were fabricated by a two-step anodization method to investigate bone cell response. Osteoblasts were seeded on nanoporous alumina membranes to investigate both short-term adhesion and proliferation and long-term functionality and matrix production. Cell adhesion and proliferation were characterized using a standard MTT assay and cell counting. The total protein content was measured after cell lysis using the BCA assay. Matrix production was characterized in terms of surface concentrations of calcium and phosphorous, components of bone matrix, using X-ray photoelectron spectroscopy (XPS). The results from nanoporous alumina membranes were compared with those of amorphous alumina, aluminum, commercially available ANOPORE and glass. Results indicate improved osteoblast adhesion and proliferation and increased matrix production after 4 weeks of study.  相似文献   
36.
Recently, sequences from a novel virus, termed GB virus C (GBV-C), were identified in serum from several patients with cryptogenic hepatitis. In the present study, the nucleotide sequence of this virus has been extended to near-genome length. GBV-C encodes a putative single large polyprotein in which the structural proteins are positioned at the N-terminal end, with the nonstructural proteins located at the C-terminal end. Amino acid sequence analysis of this large polyprotein reveals the presence of protease, helicase, and replicase motifs. Sequence alignments of the polyprotein followed by phylogenetic analyses suggest that GBV-C is a member of the Flaviviridae, most closely related to the recently described GB virus A. © 1996 Wiley-Liss, Inc.  相似文献   
37.
ABSTRACT: BACKGROUND: Neural tube defects (NTDs) are common birth defects (~1 in 1000 pregnancies in the US and Europe) that have complex origins, including environmental and genetic factors. A low level of maternal folate is one well-established risk factor, with maternal periconceptional folic acid supplementation reducing the occurrence of NTD pregnancies by 50-70%. Gene variants in the folate metabolic pathway (e.g., MTHFR rs1801133 (677 C > T) and MTHFD1 rs2236225 (R653Q)) have been found to increase NTD risk. We hypothesized that variants in additional folate/B12 pathway genes contribute to NTD risk. METHODS: A tagSNP approach was used to screen common variation in 82 candidate genes selected from the folate/B12 pathway and NTD mouse models. We initially genotyped polymorphisms in 320 Irish triads (NTD cases and their parents), including 301 cases and 341 Irish controls to perform case-control and family based association tests. Significantly associated polymorphisms were genotyped in a secondary set of 250 families that included 229 cases and 658 controls. The combined results for 1441 SNPs were used in a joint analysis to test for case and maternal effects. RESULTS: Nearly 70 SNPs in 30 genes were found to be associated with NTDs at the p < 0.01 level. The ten strongest association signals (p-value range: 0.0003-0.0023) were found in nine genes (MFTC, CDKN2A, ADA, PEMT, CUBN, GART, DNMT3A, MTHFD1 and T (Brachyury)) and included the known NTD risk factor MTHFD1 R653Q (rs2236225). The single strongest signal was observed in a new candidate, MFTC rs17803441 (OR = 1.61 [1.23-2.08], p = 0.0003 for the minor allele). Though nominally significant, these associations did not remain significant after correction for multiple hypothesis testing. CONCLUSIONS: To our knowledge, with respect to sample size and scope of evaluation of candidate polymorphisms, this is the largest NTD genetic association study reported to date. The scale of the study and the stringency of correction are likely to have contributed to real associations failing to survive correction. We have produced a ranked list of variants with the strongest association signals. Variants in the highest rank of associations are likely to include true associations and should be high priority candidates for further study of NTD risk.  相似文献   
38.
Lee SJ  Koo H  Lee DE  Min S  Lee S  Chen X  Choi Y  Leary JF  Park K  Jeong SY  Kwon IC  Kim K  Choi K 《Biomaterials》2011,32(16):4021-4029
Herein, we developed the photosensitizer, protoporphyrin IX (PpIX), conjugated glycol chitosan (GC) nanoparticles (PpIX-GC-NPs) as tumor-homing drug carriers with cellular on/off system for photodynamic imaging and therapy, simultaneously. In order to prepare PpIX-GC-NPs, hydrophobic PpIXs were chemically conjugated to GC polymer and the amphiphilic PpIX-GC conjugates formed a stable nanoparticle structure in aqueous condition, wherein conjugated PpIX molecules formed hydrophobic inner-cores and they were covered by the hydrophilic GC polymer shell. Based on the nanoparticle structure, PpIX-GC-NPs showed the self-quenching effect that is 'off' state with no fluorescence signal and phototoxicity with light exposure. It is due to the compact crystallized PpIX molecules in the nanoparticles as confirmed by dynamic light scattering and X-ray diffraction methods. However, after cellular uptake, compact nanoparticle structure gradually decreased to generate strong fluorescence signal and singlet oxygen generation when irradiated. Importantly, PpIX-GC-NPs-treated mice presented prolonged blood circulation, enhanced tumor targeting ability, and improved in vivo therapeutic efficiency in tumor-bearing mice, compared to that of free PpIX-treated mice. These results proved that this tumor-homing cellular 'on/off' nanoparticle system of PpIX-GC-NPs has a great potential for synchronous photodynamic imaging and therapy in cancer treatment.  相似文献   
39.
ObjectiveIn young women, EOC is a rare disease with an uncertain genetic and biological substrate.MethodsWe report a long follow-up of EOC patients treated at Gustave Roussy between 1990 and 2009. We matched young patients aged ≤30 years to randomly selected older patients aged ≥40 years according to known prognostic factors (i.e. FIGO stage, histology and surgical residual disease) and the date of diagnosis with a threshold at the year 2000 to balance the treatment procedures.ResultsEOC was diagnosed in 68 patients aged ≤30 years matched with 111 patients aged ≥40 years. Low-grade (LG) (i.e. serous and endometrioid) (52%, n = 35) and mucinous (i.e. 23%, n = 16 infiltrative and 12% n = 8 expansile) tumors are prevalent. High-grade (HG) tumors are rare (7%, n = 5). Early stage diseases (53%, n = 36 FIGO I/II) are predominant. Response to platinum based chemotherapy is observed to be inferior in young patients as compared to matched older patients (ORR, 29 vs 84% p = 0.0002). For HG tumors the PFS is of 0% at 5 and 10 years in younger as compared to 30% in older patients. No difference in PFS (median 4.9 vs 9.8 ms, p = 0.58) and OS (not reached vs 15.3 ms, p = 0.47) is found overall among younger and older patients respectively. The median follow-up was 72 months (range, 11–288 months). No genetic abnormalities were found.ConclusionsYoung EOC patients are most often diagnosed at an early FIGO stage with LG serous or mucinous histology. Tumors are significantly more resistant to platinum-based chemotherapy in younger patients.  相似文献   
40.
One hundred healthy infants enrolled as controls in a tuberculosis vaccine study in Nyanza Province, Kenya provided anonymized samples for DNA sequence-based typing at the HLA-A, -B, -C, -DPB1, -DQA1, -DQB1, -DRB1, and -DRB3/4/5 loci. The purpose of the study was to characterize allele frequencies in the local population, to support studies of T cell immunity against pathogens, including Mycobacterium tuberculosis. There are no detectable deviations from Hardy Weinberg proportions for the HLA-B, -C, -DRB1, -DPB1, -DQA1 and -DQB1 loci. A minor deviation was detected at the HLA-A locus due to an excess of HLA-A*02:02, 29:02, 30:02, and 68:02 homozygotes. The genotype data are available in the Allele Frequencies Net Database under identifier 3393.  相似文献   
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