Rehabilitation Applications Based on Behavioral Therapy for People With Knee Osteoarthritis: Systematic Review.

BACKGROUND: The development of digital applications based on behavioral therapies to support patients with knee osteoarthritis (KOA) has attracted increasing attention in the field of rehabilitation. This paper presents a systematic review of research on digital applications based on behavioral therapies for people with KOA. OBJECTIVE: This review aims to describe the characteristics of relevant digital applications, with a special focus on the current state of behavioral therapies, digital interaction technologies, and user participation in design. The secondary aim is to summarize intervention outcomes and user evaluations of digital applications. METHODS: A systematic literature search was conducted using the keywords "Knee Osteoarthritis," "Behavior Therapy," and "Digitization" in the following databases (from January 2013 to July 2023): Web of Science, Embase, Science Direct, Ovid, and PubMed. The Mixed Methods Assessment Tool (MMAT) was used to assess the quality of evidence. Two researchers independently screened and extracted the data. RESULTS: A total of 36 studies met the inclusion criteria and were further analyzed. Behavioral change techniques (BCTs) and cognitive behavioral therapy (CBT) were frequently combined when developing digital applications. The most prevalent areas were goals and planning (n=31) and repetition and substitution (n=27), which were frequently used to develop physical activity (PA) goals and adherence. The most prevalent combination strategy was app/website plus SMS text message/telephone/email (n=12), which has tremendous potential. This area of application design offers notable advantages, primarily manifesting in pain mitigation (n=24), reduction of physical dysfunction (n=21), and augmentation of PA levels (n=12). Additionally, when formulating design strategies, it is imperative to consider the perspectives of stakeholders, especially in response to the identified shortcomings in application design elucidated within the study. CONCLUSIONS: The results demonstrate that "goals and planning" and "repetition and substitution" are frequently used to develop PA goals and PA behavior adherence. The most prevalent combination strategy was app/website plus SMS text message/telephone/email, which has tremendous potential. Moreover, incorporating several stakeholders in the design and development stages might enhance user experience, considering the distinct variations in their requirements. To improve the efficacy and availability of digital applications, we have several proposals. First, comprehensive care for patients should be ensured by integrating multiple behavioral therapies that encompass various aspects of the rehabilitation process, such as rehabilitation exercises and status monitoring. Second, therapists could benefit from more precise recommendations by incorporating additional intelligent algorithms to analyze patient data. Third, the implementation scope should be expanded from the home environment to a broader social community rehabilitation setting.

The Effect of a Reminiscence Therapy-Based Hybrid Board Game on Anxiety and Loneliness Levels in Older Adults: An Experimental Study.

Background: Anxiety and loneliness are prevalent psychological issues faced by older adults. To tackle these concerns, group reminiscence therapy has been widely recognized as an effective non-pharmacological form of intervention. Despite its proven efficacy, the implementation of this therapy normally requires professional guidance, limiting its accessibility to specialized institutions such as hospitals. Objective: In this study, the objective is to empirically validate the effectiveness of a reminiscence therapy-based hybrid board game, Journey of Memories, in reducing anxiety and loneliness among older adults. Method: We conducted a 12-day randomized controlled study. A total of 38 elderly participants aged between 61 and 75 were recruited. They were randomly assigned to an experimental group (consisting of 20 individuals) and a control group (consisting of 18 individuals). Participants in the experimental group were required to engage in three sessions of the Journey of Memories hybrid board game intervention, with a 5-day interval between each session. No intervention was administered to participants in the control group. Results: The results found that after 3 sessions of board game-based reminiscence therapy, 20 participants in the experimental group showed significant reductions in anxiety levels (the State Anxiety subscale of State-Trait Anxiety Inventory [STAI-S] average scores decreased from 43.83 to 41.05, P = 0.000, the Trait Anxiety subscale State-Trait Anxiety Inventory [STAI-T] average scores decreased from 46.72 to 43.61, P = 0.030) and loneliness levels (UCLA Loneliness Scale [UCLA] average scores decreased from 39.11 to 36.11, P = 0.002). In addition, participants reported high scores of usability (3.77/5) and user experience (4.08/5). Conclusion: These results demonstrate that the hybrid board game can effectively reduce older adults' feelings of anxiety and loneliness while providing a satisfactory user experience, motivating them to participate in group reminiscence therapy.

Investigation on the Effectiveness of Augmented Reality Memory Training Game for Chinese Older Adults: A Randomized Controlled Trial.

Objective: To evaluate the effectiveness of augmented reality (AR) game based on n-back training paradigm as a training tool for working memory (WM) of Chinese healthy older adults. Materials and Methods: One hundred eighteen older adults self-assessed as healthy were included in this study. Individuals were randomly divided into an intervention group (n = 57) and a control group (n = 61). Interventions, consisting of a 30-minute AR game-based training and a 30-minute health science program, were administered three times per week for 4 weeks, whereas the control group was required to view a 60-minute health science program three times per week for 4 weeks. Tests, Digit Span, Corsi Block-Tapping Task (CBT), and Stroop Color and Word Test (SCWT), were conducted for all participants before and after the experiment, and the game accuracy rate of the intervention group before and after intervention was recorded. Results: There was a statistically significant difference in terms of both CBT indicators, CBT forward span (z = -2.835, P = 0.005) and CBT backward span (z = 3.285, P = 0.001), and the SCWT indicator of Stroop Words Test (SW) (z = -1.894, P = 0.048) in the two groups. The intervention group showed significant improvements in the game accuracy of both medium level (z = -3.535, P < 0.05) and of high level (z = -3.953, P < 0.05). In addition, differences were observed in subgroup analysis in the accuracy of medium level (H = 6.218, P < 0.05) and high level (H = 8.002, P < 0.05) among older people with different levels of education. Conclusion: AR game based on n-back training paradigm could improve WM of Chinese older adults, showing potential for wider promotion and adoption.

Neuronal sensorimotor integration guiding salt concentration navigation in Caenorhabditis elegans.

Animals navigate their environment by manipulating their movements and adjusting their trajectory which requires a sophisticated integration of sensory data with their current motor status. Here, we utilize the nematode Caenorhabditis elegans to explore the neural mechanisms of processing the sensory and motor information for navigation. We developed a microfluidic device which allows animals to freely move their heads while receiving temporal NaCl stimuli. We found that C. elegans regulates neck bending direction in response to temporal NaCl concentration changes in a way which is consistent with a C. elegans' navigational strategy which regulates traveling direction toward preferred NaCl concentrations. Our analysis also revealed that the activity of a neck motor neuron is significantly correlated with neck bending and activated by the decrease in NaCl concentration in a phase-dependent manner. By combining the analysis of behavioral and neural response to NaCl stimuli and optogenetic perturbation experiments, we revealed that NaCl decrease during ventral bending activates the neck motor neuron which counteracts ipsilateral bending. Simulations further suggest that this phase-dependent response of neck motor neurons can facilitate curving toward preferred salt concentrations.

A colorimetric chemosensor for sensitive and selective detection of copper(II) ions based on catalytic oxidation of 1-naphthylamine.

Rapid on-site detection of copper(II) ions (Cu2+) with high sensitivity and selectivity is of great significance in the safety monitoring of drinking water and food. Colorimetric detection is a robust fast determination method with the main drawback of low sensitivity. Herein, we developed a colorimetric chemosensor based on a colored polymer product. Via a Cu-Fenton mechanism, 1-naphthylamine (α-NA) was oxidized by H2O2 and brownish-red poly(1-naphthylamine) (PNA) was produced. The obtained Cu2+ sensor showed a linear response from 0.05 µM to 7 µM, with a detection limit of 62 nM. Our findings expanded chromogenic reaction types for colorimetric detection.

Modulation of plasmonic chiral shell growth on gold nanorods via nonchiral surfactants.

Recently, in combination with seed-mediated growth, thiolated chiral molecule-guided growth has shown great promise in obtaining chiral plasmonic nanostructures. Previously, with the assistance of chiral cysteines (Cys), we realized helical growth of plasmonic shells on gold nanorod (AuNR) seeds dispersed in cetyltrimethylammonium bromide (CTAB) solution. Herein, we further studied the roles of non-chiral cationic surfactants in tuning the helical growth. Both the counter anion and the hydrocarbon chain length of the surfactants were found to affect the formation of helical shells greatly. In particular, we exhibited surfactant-modulated conversion of the chiral shell deposition mode between layer growth and island growth. By optimizing growth conditions, an obvious plasmonic circular dichroism (PCD) response could be achieved for the island helical shell. Our findings demonstrated promising potential of nanochemical synthesis in fabricating chiral plasmonic nanostructures with small structural sizes.

Effect of Exergame Intervention on Balance Ability of Adolescents: A Randomized Controlled Trial.

Objective: Balance is a strong indicator of physical development of adolescents, and there is a trend of employing exergame for balance training. However, the effectiveness of exergame specifically designed for balance training on adolescents' balance abilities in various postures remains unclear. Materials and Methods: In this study, an exergame for balance training was developed with Kinect and a randomized controlled trial was conducted to assess its effect on balance ability development. Thirty-two healthy adolescents (age: 11.44 ± 0.51) were recruited to participate in an 8-week trial and randomly allocated to an exergame group (N = 16) or control group (N = 16). Results: The static balance test in the eagle stance posture and the dynamic balance test using the Y-Balance Test were both conducted before and after the intervention. From the results of Mann-Whitney U test, the intervention group presented greater improvement during the eagle stance test with eyes closed than the control group with P = 0.009 and P = 0.03 in left and right leg, respectively. The intervention group also showed a more significant improvement in dynamic balance (P = 0.002), which was reflected by the higher increase of composite scores. Furthermore, the balance ability when standing with nondominant leg or eyes closed, both presented higher improvements than standing with dominant leg or eyes opened, respectively. Moreover, 75% participants reported high interest and 87.5% participants expressed high engagement with exergame (score ≥4) using 5-score scale questionnaire. Conclusion: The proposed exergame for balance training could potentially promote balance training and serve as an educational tool for healthy adolescents to enhance their balance abilities.

Real-time intelligent classification of COVID-19 and thrombosis via massive image-based analysis of platelet aggregates.

Microvascular thrombosis is a typical symptom of COVID-19 and shows similarities to thrombosis. Using a microfluidic imaging flow cytometer, we measured the blood of 181 COVID-19 samples and 101 non-COVID-19 thrombosis samples, resulting in a total of 6.3 million bright-field images. We trained a convolutional neural network to distinguish single platelets, platelet aggregates, and white blood cells and performed classical image analysis for each subpopulation individually. Based on derived single-cell features for each population, we trained machine learning models for classification between COVID-19 and non-COVID-19 thrombosis, resulting in a patient testing accuracy of 75%. This result indicates that platelet formation differs between COVID-19 and non-COVID-19 thrombosis. All analysis steps were optimized for efficiency and implemented in an easy-to-use plugin for the image viewer napari, allowing the entire analysis to be performed within seconds on mid-range computers, which could be used for real-time diagnosis.

Gold-Nanoparticle-Based Chiral Plasmonic Nanostructures and Their Biomedical Applications.

As chiral antennas, plasmonic nanoparticles (NPs) can enhance chiral responses of chiral materials by forming hybrid structures and improving their own chirality preference as well. Chirality-dependent properties of plasmonic NPs broaden application potentials of chiral nanostructures in the biomedical field. Herein, we review the wet-chemical synthesis and self-assembly fabrication of gold-NP-based chiral nanostructures. Discrete chiral NPs are mainly obtained via the seed-mediated growth of achiral gold NPs under the guide of chiral molecules during growth. Irradiation with chiral light during growth is demonstrated to be a promising method for chirality control. Chiral assemblies are fabricated via the bottom-up assembly of achiral gold NPs using chiral linkers or guided by chiral templates, which exhibit large chiroplasmonic activities. In describing recent advances, emphasis is placed on the design and synthesis of chiral nanostructures with the tuning and amplification of plasmonic circular dichroism responses. In addition, the review discusses the most recent or even emerging trends in biomedical fields from biosensing and imaging to disease diagnosis and therapy.

GRID2 aberration leads to disturbance in neuroactive ligand-receptor interactions via changes to the species richness and composition of gut microbes.

OBJECTIVE: To explore the association between phenotype and the gut microbiome following damage to the GRID2 gene. METHODS: Ten wild-type (WT) mice and 11 GRID2 knockout heterozygous mice (GRID2(±)) of a similar age and weight were randomly selected. Fresh feces were collected from both groups of mice under specified pathogen-free (SPF) conditions. The bacterial genomes were extracted from the feces, the 16S rRNA genes were sequenced, and the data were analyzed to determine clustering, diversity, abundance, LEfSe, and functional differences. Differential expression and enrichment analyses of the RNA-seq and protein levels of the GRID2 gene were also performed using data in the GENE database and the new version of the Human Protein Atlas portal (www.proteinatlas.org). RESULTS: The diversity analysis showed differences in species composition between the two groups at different levels. At phylum level, compared with the WT group, the distribution was more bacteriophages but showed a lower content of Tenericutes in the GRID2(±) group. At the order level, compared with the WT group, a higher content of Actinomycetales and Bacteriophages were found in the GRID2(±) group. The species difference analysis showed that 17 species, including E. faecalis and Paracoccus spp., showed differences in content between the two groups. LEfSe analysis showed that the abundance of Clostridiaceae, Allobaculum, and other groups decreased in the GRID2(±) group compared with the WT group, while Mycoplasma, Sphingomonas, and Alphaproteobacteria increased in abundance. Functional analysis revealed eight differential functions between the WT and GRID2(±) group (P < 0.05). The most significantly disrupted were neuroactive ligand-receptor interactions (P < 9.99e-4). In addition, the differential expression and enrichment analyses performed at RNA-seq and protein levels revealed that the GRID2 gene showed organ-specific expression and was mainly enriched in the brain tissue. CONCLUSIONS: Compared with the WT group, the defective GRID2 gene affected the species richness and composition of gut microbes in the GRID2(±) mice, which in turn affected the function of gut microbes, leading to the disruption of neuroactive ligand-receptor interactions. Our findings indicate that the host gene, GRID2, can influence the abundance of a subset of gut microbes but the exact mechanisms still need further investigation.

Effects of magnesium valproate adjuvant therapy on patients with dementia: A systematic review and meta-analysis.

BACKGROUND: Current research has found contradictory results on the treatment of magnesium valproate (VPM) in patients with dementia (PwD). OBJECTIVES: Here, we conducted a meta-analysis to evaluate the efficacy and safety of VPM in the adjuvant treatment of PwD. PURPOSE: Current research has found contradictory results on the treatment of VPM in PwD. Here, we conducted a meta-analysis to evaluate the efficacy and safety of VPM in the adjuvant treatment of PwD. METHODS: MEDLINE via PubMed, Cochrane Library, EBSCO, Embase, China National Knowledge (CNKI), and Wan Fang databases were researched to gather relevant data on magnesium valproate assistant therapy for patients with dementia (PwD) by using medical subject headings and term words. RESULTS: After the final screening, 22 RCT studies (a total of 1899 participants) were included in this meta-analysis, which compared VPM adjuvant treatment with antidementia or psychotropic drug monotherapy. Significant differences were found in the scores on mini-mental state examination (P = .028), Alzheimer disease assessment scale cognitive subscale (P < .05), Bech-Rafaelsen Mania Rating Scale (P < .05), behavioral pathology in Alzheimer disease rating scale (P = .001), activities of daily living (P < .05), and Pittsburgh Sleep Quality Index (P < .05). Besides, the levels of inflammatory factors including IL-1ß, IL-6, and TNF-α were significantly lower than those in the monotherapy group (P < .05). While there was no increase in the incidence of adverse events (P = .383), VPM as an assistant therapy is generally well tolerated in PwD. CONCLUSION: By meta-analysis, evidence was found to support VPM additional used for the treatment of cognitive function, psychiatric symptoms, or disease improvement in PwD. VPM may be a potential drug to aid in the treatment of dementia patients. However, there was lack of enough evidence to classification of dementia severity in our inclusion study. More research is still needed, including clinical trials evaluating VPM as a complementary therapy.

Transforming waste into value: pomelo-peel-based nitrogen-doped carbon dots for the highly selective detection of tetracycline.

Tetracycline (TC) is widely used as a veterinary drug, and its residue in livestock products could enter the human body and cause damage. In this study, we developed an eco-friendly approach that utilized pomelo peel as a carbon source to synthesize new water-soluble N-doped carbon dots (P-NCDs) with blue fluorescence, obtaining a high quantum yield of up to 76.47% and achieving the goal of turning waste into value. Our prepared P-NCDs can selectively recognized TC, and their fluorescence was quenched based on the IFE. P-NCDs could measure the TC concentration in the linear range of 0-100 µmol L-1 with a detection limit (LOD, S/N = 3) as low as 0.045 µmol L-1. Furthermore, we have successfully applied our P-NCDs to the detection of TC in milk samples with convincing results within 90 s. Overall, our newly synthesized fluorescent sensor, P-NCDs, demonstrated huge potential to become an alternative way to detect TC in a simple, efficient, sensitive way without using any special instruments.

Improving peroxidase activity of gold nanorod nanozymes by dragging substrates to the catalysis sites via cysteine modification.

Surface chemistry control is a key means to improve substrate selectivity and enhance catalytic activity of nanozymes, a kind of novel artificial enzymes. Herein, we demonstrated that apart from chemical properties of functional groups, their spatial distance to the catalytic sites is also very important to improve the catalytic performance of nanozymes. Using cetyltrimethylammonium bromide (CTAB) coated gold nanorods (AuNR) as the example, we showed that cysteine (Cys) surface modification can greatly enhance the peroxidase activity of AuNR for the oxidation of substrate 3,3',5,5'-tetramethylbenzidine (TMB). By using cysteine derivatives, the key role of the carboxylic group in cysteine is revealed in improving substrate binding and activity enhancement. The electrostatic interactions of carboxylic groups from adsorbed cysteine molecules with protonated amino groups of TMB bring TMB molecules to the surface Au active sites and thus markedly increase catalytic activity. In contrast, despite having two carboxylic groups, glutathione (GSH) surface modification only leads to quite limited improvement of catalytic activity. We speculated that due to large molecular size of GSH, the spatial distance between TMB-GSH and Au is larger than that between TMB-Cys and Au. Furthermore, Raman characterization indicated that at high Cys coverage, they form patches on rod surface via zwitterionic interactions, which may give additional benefits by decreasing the steric hindrance of TMB diffusion to surface Au atom sites. In all, our study highlights the importance of fine surface tuning in the design of nanozymes.

Constructing chiral gold nanorod oligomers using a spatially separated sergeants-and-soldiers effect.

A sergeants-and-soldiers (S&S) effect is very useful to the fabrication of supramolecular chirality. This strategy has not yet been explored in the construction of chiral plasmonic superstructures. Herein, we demonstrate a spatially separated S&S effect in fabricating plasmonic superstructures and modulating their chiroptical responses. Specifically, chiral cysteine (Cys) molecules, acting as sergeants, are sandwiched between a gold nanorod (AuNR) core and a Au shell via AuNR-templated Au overgrowth. Cationic surfactants, CTAB (cetyltrimethylammonium bromide) or CPC (cetylpyridinium chloride), are modified on the AuNR@Cys@Au shell surface, thus spatially separating from the chiral sergeants. During the assembly process, the surfactants act as soldiers which could transfer and amplify the local chirality induced by the adsorbed chiral molecules from the plasmonic monomers to the oligomers. Huge PCD signals could be achieved in the plasmonic oligomers by finely tuning chiral sergeants and achiral soldiers, indicating the feasibility of the S&S effect in fabricating chiral plasmonic superstructures.

Effect of intensive self-management education on seizure frequency and quality of life in epilepsy patients with prodromes or precipitating factors.

PURPOSE: To explore the impact of an intensive self-management education strategy on seizure frequency and quality of life in patients with epileptic seizures with prodromes or precipitating factors. The intensive self-management education included monthly education sessions on prodromes and precipitating factors aiming to help patients to adopt self-management strategies. METHODS: Adult patients with epilepsy (PWE) able to identify prodromes or precipitating factors of their seizures were randomly assigned to an intensive education group (IEG) (n = 45) or a regular education group(REG) (n = 47). All patients received a single face-to-face self-management education session at the time of enrollment. Both groups of patients received monthly telephone follow-up for 1 year. PWE in the IEG received intensive education during each follow-up call. Primary outcomes were seizure frequency, quality of life(Quality of life in epilepsy-31 inventory scores, QOLIE 31), and drug adherence(Morisky medication adherence scale,MMAS). RESULTS: At the end of the 1-year follow-up period, seizure frequency in the IEG was significantly lower than at baseline (p < 0.001), but not in the REG(p = 0.085). Quality of life had improved significantly in the IEG (p < 0.001), but not in the REG (p = 0.073). Drug adherence was better in the IEG than in the REG (p = 0.003), and there were fewer accidental injuries in the IEG than the REG (p = 0.031). CONCLUSIONS: In PWE aware of seizure prodromes or precipitating factors, intensive self-management education may reduce seizure frequency, improve quality of life, increase adherence with antiepileptic medication and reduce accidental injuries caused by seizures.

A phenomics-based approach for the detection and interpretation of shared genetic influences on 29 biochemical indices in southern Chinese men.

BACKGROUND: Phenomics provides new technologies and platforms as a systematic phenome-genome approach. However, few studies have reported on the systematic mining of shared genetics among clinical biochemical indices based on phenomics methods, especially in China. This study aimed to apply phenomics to systematically explore shared genetics among 29 biochemical indices based on the Fangchenggang Area Male Health and Examination Survey cohort. RESULT: A total of 1999 subjects with 29 biochemical indices and 709,211 single nucleotide polymorphisms (SNPs) were subjected to phenomics analysis. Three bioinformatics methods, namely, Pearson's test, Jaccard's index, and linkage disequilibrium score regression, were used. The results showed that 29 biochemical indices were from a network. IgA, IgG, IgE, IgM, HCY, AFP and B12 were in the central community of 29 biochemical indices. Key genes and loci associated with metabolism traits were further identified, and shared genetics analysis showed that 29 SNPs (P < 10- 4) were associated with three or more traits. After integrating the SNPs related to two or more traits with the GWAS catalogue, 31 SNPs were found to be associated with several diseases (P < 10- 8). Using ALDH2 as an example to preliminarily explore its biological function, we also confirmed that the rs671 (ALDH2) polymorphism affected multiple traits of osteogenesis and adipogenesis differentiation in 3 T3-L1 preadipocytes. CONCLUSION: All these findings indicated a network of shared genetics and 29 biochemical indices, which will help fully understand the genetics participating in biochemical metabolism.

Development and validation of the Chinese Version of the Adult Epilepsy Self-Management Scale (C-ESMS) in Western China.

PURPOSE: To develop and validate the Epilepsy Self-Management Scale (ESMS) for Chinese persons with epilepsy (PWE). METHODS: On the basis of ESMS, the standard translation procedure was used to set up the Chinese version of the ESMS (C-ESMS). A consecutive cohort of PWE admitted in Sichuan Provincial People's Hospital were recruited randomly from May 2017 to December 2017 and required to complete the C-ESMS. Project analysis was employed to test the homogeneity of each dimension. Content validity was evaluated by experts. Exploratory factor analysis and confirmatory factor analysis (CFA) were applied to assess the validity. Cronbach's alpha was used to evaluate the reliability. RESULTS: Of the 400 completed C-ESMS forms, only 394 (98.5%) were suitable for analysis. The C-ESMS included 34 items and five dimensions, after removing four and modifying three items. The correlation coefficient of all 34 items was greater than 0.4. Each item level (I-CVI) and scale level CVI (S-CVI) was equal to 1. Five factors were extracted and together they explained 51.24% of the data's variance. The factor load of each item was 0.446-0.843. The CFA showed that CMIN/DF was 1.325, goodness of fit was 0.835, comparative fit index was 0.921, and root mean square error of approximation was 0.041. The total Cronbach's alpha of the scale was 0.848, and Cronbach's alpha in each dimension was 0.784-0.845. CONCLUSION: The C-ESMS exhibited good reliability and validity for adult PWE in western China.

Expression and characterization of Kunitz domain 3 and C-terminal of human tissue factor pathway inhibitor-2.

Human tissue factor pathway inhibitor-2 (hTFPI-2) is a serine protease inhibitor and its inhibitory activity is enhanced by heparin. The Kunitz domain 3 and Cterminal of hTFPI-2 (hTFPI-2/KD3C), which has the activity toward heparin calcium, have been successfully expressed in Pichia pastoris and purified by SPSepharose and heparin-Sepharose chromatography. The Fourier transformed infrared spectroscopy (FTIR), Raman spectroscopy, and circular dichroism (CD) experiment results implied that hTFPI-2/KD3C contained small contents of alpha-helix and beta-strand, but large amounts of random coil and two kinds of disulfide bonds, gauche-gauche-gauche (ggg) and trans-gauchetrans (tgt). The interaction of hTFPI-2/KD3C with heparin calcium was investigated by CD. It was found that heparin calcium induced b-strands in hTFPI-2/ KD3C to different extents depending on the ratio of hTFPI-2/KD3C and heparin calcium.

Spectroscopic analysis on the effect of temperature on Kunitz domain 1 of human tissue factor pathway inhibitor-2.

The conformation of Kunitz domain 1 of human tissue factor pathway inhibitor-2 (hTFPI-2/KD1) has been studied by fourier transform infrared spectroscopy, circular dichroism, and Raman spectroscopy. It was found that hTFPI-2/KD1 contained approximately 17% alpha-helices, 24% beta-strands, 46% random coils, 13% beta-turns, and two kinds of disulfide bonds(ggg and tgt) at 25 degrees C. The detailed conformational changes of the heated protein observed by fourier transform infrared spectroscopy, circular dichroism and Raman spectroscopy revealed that hTFPI-2/KD1 was thermally stable. However, KD1 could form an intermediate form at high temperature, then return to its normal conformation when the temperature was lowered. Activity assays also showed that hTFPI-2/KD1 was able to keep its inhibitory activity on plasmin after being heated to 80 degrees C for 5 min.