NMR characterization of the electrostatic interaction of the basic residues in HDGF and FGF2 during heparin binding.

Electrostatic interaction is a major driving force in the binding of proteins to highly acidic glycosaminoglycan, such as heparin. Although NMR backbone chemical shifts have generally been used to identify the heparin-binding site on a protein, however, there is no correlation between the binding free energies and the perturbed backbone chemical shifts for individual residues. The binding event occurs at the end of a side chain of basic residue, and does not require causing significant alterations in the backbone environment at a distance of multiple bonds. We used the H2CN NMR pulse sequence to detect heparin binding through the side-chain resonances Hε-Cε-Nζ of Lys and Hδ-Cδ-Nε of Arg in the two proteins of hepatoma-derived growth factor (HDGF) and basic fibroblast growth factor (FGF2). H2CN titration experiments revealed chemical shift perturbations in the side chains, which were correlated with the free energy changes in various mutants. The residues K19 in HDGF and K125 in FGF2 demonstrated the most significant perturbations, consistent with our previous observation that the two residues are crucial for binding. The result suggests that H2CN NMR provides a precise evaluation for the electrostatic interactions. The discrepancy observed between backbone and side chain chemical shifts is correlated to the solvent accessibility of residues that the K19 and K125 backbones are highly buried with the restricted backbone conformation and are not strongly affected by the events at the end of the side chains.

Nuclear magnetic resonance structure of the cytoplasmic tail of heparin binding EGF-like growth factor (proHB-EGF-CT) complexed with the ubiquitin homology domain of Bcl-2-associated athanogene 1 from Mus musculus (mBAG-1-UBH).

The membrane form of heparin binding EGF-like growth factor (proHB-EGF) yields secreted HB-EGF and a membrane-anchored cytoplasmic tail (proHB-EGF-CT), which may be targeted to the nuclear membrane after a shedding stimulus. Bcl-2-associated athanogene 1 (BAG-1) accumulates in the nuclei and inhibits apoptosis in adenoma-derived cell lines. The maintenance of high levels of nuclear BAG-1 enhances cell survival. However, the ubiquitin homology domain of BAG-1 from Mus musculus (mBAG-1-UBH) is proposed to interact with proHB-EGF-CT, and this interaction may enhance the cytoprotection against the apoptosis inducer. The mechanism of the synergistic anti-apoptosis function of proHB-EGF-CT and mBAG-1-UBH is still unknown. We offer a hypothesis that proHB-EGF-CT can maintain high levels of nuclear BAG-1. In this study, we first report the three-dimensional nuclear magnetic resonance structure of proHB-EGF-CT complexed with mBAG-1-UBH. In the structure of the complex, the residues in the C-terminus and one turn between ß-strands ß1 and ß2 of mBAG-1-UBH bind to two terminals of proHB-EGF-CT, which folds into a loop with end-to-end contact. This end-to-end folding of proHB-EGF-CT causes the basic amino acids to colocalize and form a positively charged groove. The dominant forces in the binding interface between proHB-EGF-CT and mBAG-1-UBH are charge-charge interactions. On the basis of our mutagenesis results, the basic amino acid cluster in the N-terminus of proHB-EGF-CT is the crucial binding site for mBAG-1-UBH, whereas another basic amino acid in the C-terminus facilitates this interaction. Interestingly, the mBAG-1-UBH binding region on the proHB-EGF-CT peptide is also involved in the region found to be important for nuclear envelope targeting, supporting the hypothesis that proHB-EGF-CT is most likely able to trigger the nuclear translocation of BAG-1 in keeping its level high.

Mood disorders after traumatic brain injury in adolescents and young adults: a nationwide population-based cohort study.

OBJECTIVE: To delineate the relationship between traumatic brain injury (TBI) and mood disorders from population-based data in Taiwan. STUDY DESIGN: This prospectively followed cohort study involved a subset of the National Health Insurance Research Database containing complete inpatient and outpatient data of 1 million randomly drawn beneficiaries. We included 10- to 24-year-old patients (n = 15,203) receiving the diagnosis of TBI in ambulatory visits or hospitalization from 2000-2004 and their age- and sex-matched comparison insureds using health service in the same year (n = 76,015). Diagnosis of mood disorders was recorded within 5 years after the traumatic event or index use of health service. Baseline demographics, clinical characteristics, and premorbid psychiatric conditions were compared using χ(2) analysis. Increased risk during the 5-year follow-up period was represented by crude and adjusted hazard ratios with 95% CI using a Cox proportional hazard regression. RESULTS: A total of 451/15,203 patients with TBI (2.97%) received a diagnosis of mood disorders in the 5-year follow-up period compared with 1153/97,445 individuals (1.52%) without antecedent TBI. After adjusting for select premorbid comorbidities, TBI remained a significant predisposing factor with a 1.96-fold (95% CI 1.74-2.22) increase in risk of mood disorders. CONCLUSIONS: Our findings show a higher likelihood of manifesting mood disorders in adolescents and young adults who sustained a prior TBI. Health professionals should carefully monitor both the physical and psychological impacts of head trauma.

FeoC from Klebsiella pneumoniae contains a [4Fe-4S] cluster.

Iron is essential for pathogen survival, virulence, and colonization. Feo is suggested to function as the ferrous iron (Fe(2+)) transporter. The enterobacterial Feo system is composed of 3 proteins: FeoB is the indispensable component and is a large membrane protein likely to function as a permease; FeoA is a small Src homology 3 (SH3) domain protein that interacts with FeoB; FeoC is a winged-helix protein containing 4 conserved Cys residues in a sequence suitable for harboring a putative iron-sulfur (Fe-S) cluster. The presence of an iron-sulfur cluster on FeoC has never been shown experimentally. We report that under anaerobic conditions, the recombinant Klebsiella pneumoniae FeoC (KpFeoC) exhibited hyperfine-shifted nuclear magnetic resonance (NMR) and a UV-visible (UV-Vis) absorbance spectrum characteristic of a paramagnetic center. The electron paramagnetic resonance (EPR) and extended X-ray absorption fine structure (EXAFS) results were consistent only with the [4Fe-4S] clusters. Substituting the cysteinyl sulfur with oxygen resulted in significantly reduced cluster stability, establishing the roles of these cysteines as the ligands for the Fe-S cluster. When exposed to oxygen, the [4Fe-4S] cluster degraded to [3Fe-4S] and eventually disappeared. We propose that KpFeoC may regulate the function of the Feo transporter through the oxygen- or iron-sensitive coordination of the Fe-S cluster.

Crystal structure of the Klebsiella pneumoniae NFeoB/FeoC complex and roles of FeoC in regulation of Fe2+ transport by the bacterial Feo system.

Feo is a transport system commonly used by bacteria to acquire environmental Fe(2+). It consists of three proteins: FeoA, FeoB, and FeoC. FeoB is a large protein with a cytosolic N-terminal domain (NFeoB) that contains a regulatory G protein domain and a helical S domain. The C-terminal region of FeoB is a transmembrane domain that likely acts as the Fe(2+) permease. NFeoB has been shown to form a trimer pore that may function as an Fe(2+) gate. FeoC is a small winged-helix protein that possesses four conserved cysteine residues with a consensus sequence that likely provides binding sites for the [Fe-S] cluster. Therefore, FeoC is presumed to be an [Fe-S] cluster-dependent regulator that directly controls transcription of the feo operon. Despite the apparent significance of the Feo system, however, the function of FeoC has not been experimentally demonstrated. Here, we show that Klebsiella pneumoniae FeoC (KpFeoC) forms a tight complex with the intracellular N-terminal domain of FeoB (KpNFeoB). The crystal structure of the complex reveals that KpFeoC binds to KpNFeoB between the switch II region of the G protein domain and the effector S domain and that the long KpFeoC W1 loop lies above the KpNFeoB nucleotide-binding site. These interactions suggest that KpFeoC modulates the guanine nucleotide-mediated signal transduction process. Moreover, we showed that binding of KpFeoC disrupts pore formation by interfering with KpNFeoB trimerization. These results provide strong evidence suggesting that KpFeoC plays a crucial role in regulating Fe(2+) transport in Klebsiella pneumonia in addition to the presumed gene regulator role.

Population based study on patients with traumatic brain injury suggests increased risk of dementia.

OBJECTIVE: The relationship between traumatic brain injury (TBI) and the risk of dementia remains controversial. This population based study was designed to estimate and compare the risk of dementia in TBI and non-TBI individuals during the 5 year period after TBI. METHODS: This study was a retrospective cohort study. Data were obtained from the Longitudinal Health Insurance Database 2000. We included 44,925 patients receiving ambulatory or hospital care and 224,625 non-TBI patients; patients were matched for sex, age and year of index use of healthcare. Patients <15 years of age and those admitted to the intensive care unit were excluded. Each individual was studied for 5 years to identify the subsequent development of dementia. Data were analysed by Cox proportional hazard regression. RESULTS: During the 5 year follow-up period, 1196 TBI (2.66%) and 224,625 non-TBI patients (1.53%) patients developed dementia. During the 5 year follow-up period, TBI was independently associated with a 1.68 (range 1.57-1.80) times greater risk of dementia after adjusting for sociodemographic characteristics and selected comorbidities. CONCLUSIONS: The findings of this study suggest an increased risk of dementia among individuals with TBI. We suggest the need for more intensive medical monitoring and health education in individuals with TBI.

High 18F-fluoro-2-deoxy-D-glucose uptake in adult-type rhabdomyoma of the larynx.

Rhabdomyomas are rare benign mesenchymal tumors of the skeletal muscles and uncommon in the head and neck region. Laryngeal rhabdomyomas are much rarer. We present the case of a 32-year-old woman who was admitted to our hospital for shortness of breath due to pneumothorax. As otolaryngologists, we were consulted for a soft tissue tumor over the left side of the larynx that was accidentally found on the chest computed tomography (CT). The patient underwent laryngomicrosurgery for tumor biopsy, and histological examination revealed a laryngeal rhabdomyoma. After the operation, magnetic resonance imaging of the neck was performed and the tumor was suspected as rhabdomyosarcoma. Positron emission tomography/computed tomography (PET/CT) showed an 18F-fluoro-2-deoxy-D-glucose (FDG)-avid soft tissue mass on the left side of the larynx. After complete tumor removal via transoral laser microsurgery, no recurrence was reported for 5 years.

Cost Utility Analysis of Multidisciplinary Postacute Care for Stroke: A Prospective Six-Hospital Cohort Study.

Background: Few studies have compared the optimal duration and intensity of organized multidisciplinary neurological/rehabilitative care delivered in a regional/district hospital with the standard rehabilitative care delivered in the general neurology/rehabilitation ward of a medical center. This study measured functional outcomes and conducted cost-utility analysis of an organized multidisciplinary postacute care (PAC) project in secondary care compared with standard rehabilitative care delivered in tertiary care. Methods: This prospective cohort study enrolled 1,476 patients who had a stroke between March 2014 and March 2018 and had a modified Rankin scale score of 2-4. After exact matching for age ± 1 year, sex, year of stroke diagnosis, nasogastric tube, and Foley catheter and propensity score matching for the other covariates, we obtained 120 patients receiving PAC (the PAC group) from four regional/district hospitals and 120 patients not receiving PAC (the non-PAC group) from two medical centers. Results: At baseline, the non-PAC group showed significantly better functional outcomes than the PAC group, including EuroQol-5 dimensions (EQ-5D), Mini-Mental State Examination (MMSE) and Barthel index (BI). During weeks 7-12 of rehabilitation, improvements in all functional outcomes were significantly larger in the PAC group (P < 0.001) except for Functional Oral Intake Scale (FOIS). Cost-utility analysis revealed that the PAC group had a significantly lower mean (± standard deviation) of direct medical costs (US$3,480 ± $1,758 vs. US$3,785 ± $3,840, P < 0.001) and a significantly higher average gain of quality-adjusted life years (0.1993 vs. 0.1233, P < 0.001). The PAC project was an economically "dominant" strategy. Conclusions: The PAC project saved costs and significantly improved the functional outcomes of patients with stroke with slight to moderately severe disabilities. Randomized control trials are required to corroborate these results.

Predicting 30-Day Readmission for Stroke Using Machine Learning Algorithms: A Prospective Cohort Study.

Background: Machine learning algorithms for predicting 30-day stroke readmission are rarely discussed. The aims of this study were to identify significant predictors of 30-day readmission after stroke and to compare prediction accuracy and area under the receiver operating characteristic (AUROC) curve in five models: artificial neural network (ANN), K nearest neighbor (KNN), random forest (RF), support vector machine (SVM), naive Bayes classifier (NBC), and Cox regression (COX) models. Methods: The subjects of this prospective cohort study were 1,476 patients with a history of admission for stroke to one of six hospitals between March, 2014, and September, 2019. A training dataset (n = 1,033) was used for model development, and a testing dataset (n = 443) was used for internal validation. Another 167 patients with stroke recruited from October, to December, 2019, were enrolled in the dataset for external validation. A feature importance analysis was also performed to identify the significance of the selected input variables. Results: For predicting 30-day readmission after stroke, the ANN model had significantly (P < 0.001) higher performance indices compared to the other models. According to the ANN model results, the best predictor of 30-day readmission was PAC followed by nasogastric tube insertion and stroke type (P < 0.05). Using a machine learning ANN model to obtain an accurate estimate of 30-day readmission for stroke and to identify risk factors may improve the precision and efficacy of management for these patients. Conclusion: Using a machine-learning ANN model to obtain an accurate estimate of 30-day readmission for stroke and to identify risk factors may improve the precision and efficacy of management for these patients. For stroke patients who are candidates for PAC rehabilitation, these predictors have practical applications in educating patients in the expected course of recovery and health outcomes.

Impact of Multidisciplinary Stroke Post-Acute Care on Cost and Functional Status: A Prospective Study Based on Propensity Score Matching.

Few papers discuss how the economic burden of patients with stroke receiving rehabilitation courses is related to post-acute care (PAC) programs. This is the first study to explore the economic burden of stroke patients receiving PAC rehabilitation and to evaluate the impact of multidisciplinary PAC programs on cost and functional status simultaneously. A total of 910 patients with stroke between March 2014 and October 2018 were separated into a PAC group (at two medical centers) and a non-PAC group (at three regional hospitals and one district hospital) by using propensity score matching (1:1). A cost-illness approach was employed to identify the cost categories for analysis in this study according to various perspectives. Total direct medical cost in the per-diem-based PAC cohort was statistically lower than that in the fee-for-service-based non-PAC cohort (p < 0.001) and annual per-patient economic burden of stroke patients receiving PAC rehabilitation is approximately US $354.3 million (in 2019, NT $30.5 = US $1). Additionally, the PAC cohort had statistical improvement in functional status vis-à-vis the non-PAC cohort and total score of each functional status before rehabilitation and was also statistically significant with its total score after one-year rehabilitation training (p < 0.001). Early stroke rehabilitation is important for restoring health, confidence, and safe-care abilities in these patients. Compared to the current stroke rehabilitation system, PAC rehabilitation shortened the waiting time for transfer to the rehabilitation ward and it was indicated as an efficient policy for treatment of stroke in saving medical cost and improving functional status.

Multidisciplinary Care after Acute Care for Stroke: A Prospective Comparison between a Multidisciplinary Post-Acute Care Group and a Standard Group Matched by Propensity Score.

In this large-scale prospective cohort study, a propensity score matching method was applied in a natural experimental design to investigate how post-acute care (PAC) after stroke affects functional status and to identify predictors of functional status. The main objective of this study was to examine longitudinal changes in various measures of functional status in stroke patients and predictors of scores for these measures before and after PAC. A group of patients who had received PAC for stroke at one of two medical centers (PAC group, n = 273) was compared with a group who had received standard care for stroke at one of four hospitals (three regional hospital and one district hospital; non-PAC group, n = 273) in Taiwan from March, 2014, to October, 2018. The patients completed the functional status measures before rehabilitation, the 12th week and the 1st year after rehabilitation. Generalized estimating equations were used to estimate differences-in-differences models for examining the effects of PAC. The average age was 68.0 (SD = 8.1) years, and males accounted for 57.9%. During the follow-up period, significant risk factors for poor functional outcomes were advanced age, hemorrhagic stroke, and poor function scores before rehabilitation (p < 0.05). Between-group comparisons at subsequent time points revealed significantly higher functional status scores in the PAC group versus the non-PAC group (p < 0.001). Notably, for all functional status measures, between-group differences in total scores significantly increased over time from baseline to 1 year post-rehabilitation (p < 0.001). The contribution of this study is its further elucidation of the clinical implications and health policy implications of rehabilitative care after stroke. Specifically, it improves understanding of the effects of PAC in stroke patients at different follow-up times. Therefore, a policy implication of this study is that standard care for stroke should include intensive rehabilitative PAC to maximize recovery of overall function.

Structural fold, conservation and Fe(II) binding of the intracellular domain of prokaryote FeoB.

FeoB is a G-protein coupled membrane protein essential for Fe(II) uptake in prokaryotes. Here, we report the crystal structures of the intracellular domain of FeoB (NFeoB) from Klebsiella pneumoniae (KpNFeoB) and Pyrococcus furiosus (PfNFeoB) with and without bound ligands. In the structures, a canonical G-protein domain (G domain) is followed by a helical bundle domain (S-domain), which despite its lack of sequence similarity between species is structurally conserved. In the nucleotide-free state, the G-domain's two switch regions point away from the binding site. This gives rise to an open binding pocket whose shallowness is likely to be responsible for the low nucleotide-binding affinity. Nucleotide binding induced significant conformational changes in the G5 motif which in the case of GMPPNP binding was accompanied by destabilization of the switch I region. In addition to the structural data, we demonstrate that Fe(II)-induced foot printing cleaves the protein close to a putative Fe(II)-binding site at the tip of switch I, and we identify functionally important regions within the S-domain. Moreover, we show that NFeoB exists as a monomer in solution, and that its two constituent domains can undergo large conformational changes. The data show that the S-domain plays important roles in FeoB function.

Multidiscipline Stroke Post-Acute Care Transfer System: Propensity-Score-Based Comparison of Functional Status.

Few studies have investigated the characteristics of stroke inpatients after post-acute care (PAC) rehabilitation, and few studies have applied propensity score matching (PSM) in a natural experimental design to examine the longitudinal impacts of a medical referral system on functional status. This study coupled a natural experimental design with PSM to assess the impact of a medical referral system in stroke patients and to examine the longitudinal effects of the system on functional status. The intervention was a hospital-based, function oriented, 12-week to 1-year rehabilitative PAC intervention for patients with cerebrovascular diseases. The average duration of PAC in the intra-hospital transfer group (31.52 days) was significantly shorter than that in the inter-hospital transfer group (37.1 days) (p < 0.001). The intra-hospital transfer group also had better functional outcomes. The training effect was larger in patients with moderate disability (Modified Rankin Scale, MRS = 3) and moderately severe disability (MRS = 4) compared to patients with slight disability (MRS = 2). Intensive post-stroke rehabilitative care delivered by per-diem payment is effective in terms of improving functional status. To construct a vertically integrated medical system, strengthening the qualified local hospitals with PAC wards, accelerating the inter-hospital transfer, and offering sufficient intensive rehabilitative PAC days are the most essential requirements.

Backbone resonance assignments of the PRYSPRY domain of TRIM25.

TRIM25 is a member of the tripartite motif (TRIM) family and has been implicated in the regulation of innate immune signaling via the RIG-I (retinoic acid-inducible gene-I) pathway for antiviral defense. As the essential first step towards the structural and functional characterization of the TRIM25/RIG-I interaction, the backbone resonance of the PRYSPRY domain of TRIM25 is assigned here based on triple-resonance experiments using uniformly [(2)H, (13)C, (15)N]-labeled protein.

¹H, ¹³C and ¹5N resonance assignments of Ca²âº-bound human S100A15.

S100A15 (koebnerisin) is overexpressed in psoriatic skin and displays distinct localizations in skin and breast with divergent functions in inflammation. Here we report the backbone and side-chain resonance assignments for the Ca(2+)-bound human S100A15.

Prevalence, incidence, and comorbidity of clinically diagnosed obsessive-compulsive disorder in Taiwan: a national population-based study.

Obsessive-compulsive disorder (OCD) is a chronic debilitating anxiety disorder significant in intrusive thoughts and compensation repetitive behaviors. Few studies have reported on this condition Asia. This study estimated the prevalence, incidence and psychiatric comorbidities of OCD in Taiwan. We identified study subjects for 2000-2008 with a principal diagnosis of OCD according to the International Classification of Disease, 9th Revision, Clinical Modification (ICD-9-CM) diagnostic criteria by using National Health Research Institute database. These patients received either outpatient or inpatient care for their condition. Rates were directly age- and sex-adjusted to the 2004 Taiwan population distribution. The estimated mean annual incidence was 27.57 per 10(5) inhabitants and the one year prevalence was 65.05 per 10(5) inhabitants. Incidence and prevalence increased with age, peaking at age 18-24 years in males and at 35-44 years in females. About 53% of adults (≥18 years) and 48% of child and adolescent patients (6-17 years) had one or more comorbid psychiatric conditions. The most common comorbid diagnosis was depressive disorders for both adult and child-adolescent patients. We found a lower prevalence and incidence of clinically diagnosed OCD than that of community studies. Many Asian patients with OCD also had various psychiatric comorbidities, a clinically relevant finding.