Offline User Authentication Ensuring Non-Repudiation and Anonymity.

User authentication is the key to ensuring that only authorized users can deal with specific affairs and access services. Applications or systems possessing different properties or requirements need different authentication schemes. For example, some institutions or companies need executives to manage or inspect their corresponding departments while the inspected department should not know who the executives are but only can verify their legitimacy. This paper designs a non-repudiation and anonymity-ensured user authentication system to meet the mentioned special requirements. We also propose a user authentication scheme to ensure that the designed system can work as claimed. In the system, a department is equipped with an authentication device, namely the department authentication device, to authenticate an executive while the executive's identity is not revealed to the department and only the department's authentication device can identify the executive for non-repudiation. An executive is equipped with an authentication device to have himself/herself authenticated by the department's authentication device. Moreover, authentication data stored in an executive's authentication device does not need to be updated even when management personnel changes are made.

[The relationship between medication adherence and rehospitalization: a prospective study of schizophrenia patients discharged from psychiatric acute wards].

BACKGROUND: Antipsychotics have been regarded as the most effective therapy for schizophrenia; however, Taiwan's non-adherence rate for prescribed antipsychotics of 50-80% is an important issue that relates directly and significantly to schizophrenia patient relapse rates. PURPOSE: This study examines the correlational and predictive relationships between medication adherence and rehospitalization in schizophrenia patients discharged from an acute ward. METHODS: This study used a prospective research design. Schizophrenia patients discharged from a psychiatric acute ward who stated their plan to live in the community were recruited as participants. Participant medication adherence was assessed via home visits during the 6-month follow-up period using scales including the Medication Adherence Questionnaire (MAQ), drug attitudes, and regimen knowledge. Rehospitalization data were retrieved from electronic medical records. Relationships between medication adherence and rehospitalization were analyzed using t-tests and regression analysis. RESULTS: Seventy-seven patients with schizophrenia discharged from the acute ward were recruited in accordance with sampling criteria. The majority were male, young, unmarried, had poorer global function, had 12 years of education, and were not rehospitalized during the past 6-month period. Using binomial regression analysis, we found the relative risk for number of rehospitalizations during the 6-month period to be significantly less and the average scores for the total scale, attitude subscale, and knowledge subscale of medication adherence to have increased (0.194-0.79 times). CONCLUSIONS/IMPLICATIONS FOR PRACTICE: Our findings support that better medication adherence in people with schizophrenia decreases rehospitalization risk. We urge clinicians to develop sensitive interventions to promote antipsychotics adherence in this population.

Repeated colonization by multi-drug-resistant Acinetobacter calcoaceticus-A. baumannii complex and changes in antimicrobial susceptibilities in surgical intensive care units.

BACKGROUND: A nosocomial outbreak of multi-drug-resistant Acinetobacter calcoaceticus-A. baumannii (MDR-ACB) complex infection occurred in a newly constructed building at a 2,500-bed tertiary medical center in Taiwan. METHODS: An investigation was carried out by molecular approaches to trace the bacteria. Antimicrobial susceptibilities, risk factors, and the occurrence of nosocomial MDR-ACB infections were investigated. From January to December 2009, 53 patients were infected with MDR-ACB, and 23 environmental surveys were performed in two surgical intensive care units (ICUs) within the new building. Forty-two clinical isolates were obtained from patients and 22 samples from nine environmental surveys. RESULTS: Forty clinical isolates (95.2%) and 18 environmental samples (81.8%) were positive for MDR-ACB of type A, the predominant outbreak strain. This strain was identical to that isolated in an outbreak in the old hospital in 2006, as proved by repetitive extragenic palindromic-based polymerase chain reaction and pulsed-field gel electrophoresis. Although the outbreak isolates contained blaOXA-23-like and blaOXA-51-like genes, analysis of the antimicrobial susceptibilities demonstrated increases in resistance to cefepime and imipenem-cilastatin in MDR-ACB isolated in the later outbreak. CONCLUSIONS: Not only patients or healthcare workers, but also medical equipment, might have carried the predominant outbreak strain from the old district to the new building. Therefore, even in a new environment, infection control programs must be enforced continually, and healthcare providers must be educated repeatedly to prevent recurrent outbreaks of MDR-ACB infection in the hospital setting.

A robust and novel dynamic-ID-based authentication scheme for care team collaboration with smart cards.

Nowadays, users/patients may gain desired medical services on-line because of the rapid development of computer network technologies. Conventional healthcare services are provided by a single server. However, care team collaboration by integrating services is the key to improve financial and clinical performance. How a user/patient accesses desired medical services provided by multiple servers becomes a challenge to realize care team collaboration. User authentication plays an important role to protect resources or services from being accessed by unauthorized users. In this paper, we first discuss the perceived security drawbacks of pervasive smart-card-based remote user authentication schemes. Then, we propose a novel dynamic-ID-based user authentication scheme based on elliptic curve cryptosystem (ECC) for multi-server environment with smart cards. The proposed scheme ensures user anonymity and computational efficiency and complies with essential requirements of a secure smart-card-based authentication scheme for multi-server environment to enable care team collaboration.

A uniqueness-and-anonymity-preserving remote user authentication scheme for connected health care.

Connected health care provides new opportunities for improving financial and clinical performance. Many connected health care applications such as telecare medicine information system, personally controlled health records system, and patient monitoring have been proposed. Correct and quality care is the goal of connected heath care, and user authentication can ensure the legality of patients. After reviewing authentication schemes for connected health care applications, we find that many of them cannot protect patient privacy such that others can trace users/patients by the transmitted data. And the verification tokens used by these authentication schemes to authenticate users or servers are only password, smart card and RFID tag. Actually, these verification tokens are not unique and easy to copy. On the other hand, biometric characteristics, such as iris, face, voiceprint, fingerprint and so on, are unique, easy to be verified, and hard to be copied. In this paper, a biometrics-based user authentication scheme will be proposed to ensure uniqueness and anonymity at the same time. With the proposed scheme, only the legal user/patient himself/herself can access the remote server, and no one can trace him/her according to transmitted data.

Brain reorganization after bilateral arm training and distributed constraint-induced therapy in stroke patients: a preliminary functional magnetic resonance imaging study.

BACKGROUND: Bilateral arm training (BAT) and constraint-induced therapy (CIT) have shown beneficial effects in improving motor control and function of the upper extremities (UE) for patients with stroke. Thus far, no study has directly investigated the relative effects of BAT versus CIT on brain reorganization. This study compared the effects of BAT with distributed CIT (dCIT) on brain reorganization and motor function in 6 stroke patients. METHODS: In a pre-post randomized controlled trial, 6 stroke patients received BAT (intensive bilateral simultaneous and symmetrical training) or dCIT (restraint of the unaffected UE combined with intensive training of the affected UE) for a period of 3 weeks, 5 days per week. Functional magnetic resonance imaging (fMRI) examination and 3 clinical measures (Fugl-Meyer Assessment, Action Research Arm Test, and Motor Activity Log) were administered before and after the intervention. RESULTS: After intervention, patients showed varied patterns of fMRI changes and improved motor function. Two well-recovered patients, one from each group, showed large increases in bilateral hemisphere activation, especially in the ipsilesional hemisphere during affected hand movement and in the contralesional hemisphere during unaffected hand movement. During bilateral elbow movement, 3 of the 4 BAT patients showed increased bilateral cerebellum activation, especially in the left cerebellum, whereas 2 dCIT patients showed decreased cerebellar activation. CONCLUSIONS: The findings of this preliminary research revealed that neuroplastic changes after stroke motor rehabilitation may be specific to the intervention. Further research using a larger sample and more complex fMRI tasks is warranted to validate the findings.

The effects of bilateral arm training on motor control and functional performance in chronic stroke: a randomized controlled study.

BACKGROUND: Most studies of bilateral arm training (BAT) did not employ a randomized controlled trial design and involved very limited functional training tasks. OBJECTIVE: Compare the effects of BAT with control intervention (CI) on motor control and motor performance of the upper extremity and also functional gains in patients with chronic stroke. METHODS: . This 2-group randomized controlled trial with pretreatment and posttreatment measures enrolled 33 stroke patients (mean age = 53.85 years) 6 to 67 months after onset of a first stroke. They received either a BAT program concentrating on both upper extremities moving simultaneously in functional tasks by symmetric patterns or CI (control treatment) for 2 hours on weekdays for 3 weeks. Outcome measures included kinematic analyses assessing motor control strategies for unilateral and bimanual reaching and clinical measures involving the Fugl-Meyer Assessment (FMA) of motor-impairment severity and the Functional Independence Measure (FIM) and the Motor Activity Log (MAL) evaluating functional ability. RESULTS: After treatment, the BAT group showed better temporal and spatial efficiency during unilateral and bilateral tasks and less online error correction only during the bilateral task than the control group. The BAT group showed a significantly greater improvement in the FMA than the control group but not in the FIM and MAL. CONCLUSIONS: Relative to CI, BAT improved the spatiotemporal control of the affected arm in both bilateral and unilateral tasks, decreased online corrections to perform bilateral tasks, and reduced motor impairment. These findings support the use of BAT to improve motor control and motor function of the affected upper limb in stroke patients.

Responsiveness and validity of three outcome measures of motor function after stroke rehabilitation.

BACKGROUND AND PURPOSE: This study investigated and compared the responsiveness and validity of the Fugl-Meyer Assessment (FMA), the Action Research Arm Test (ARAT), and the Wolf Motor Function Test (WMFT) for patients after stroke rehabilitation. METHODS: A total of 57 patients with stroke received 1 of 3 rehabilitation treatments for 3 weeks. At pretreatment and posttreatment, the 3 outcome measures, as well as the Functional Independence Measure (FIM) as the external criterion, were administered. The standardized response mean (SRM) and the Wilcoxon signed rank test were used to examine the responsiveness. Construct validity and predictive validity were examined by the Spearman correlation coefficient (rho). RESULTS: The responsiveness of the FMA, ARAT, and WMFT functional ability scores was large (SRM=0.95-1.42), whereas the WMFT performance time score was small (SRM=0.38). The responsiveness of the FMA was significantly larger than those of the ARAT and the WMFT-TIME, but not the WMFT functional ability scores. With respect to construct validity, correlations between the FMA and other measures were relatively high (rho=0.42-0.76). The FMA and the WMFT performance time scores at pretreatment had moderate predictive validity with the FIM scores at posttreatment (rho=0.42-0.47). In addition, the ARAT and the WMFT functional ability scores revealed a low predictive validity with the FIM (rho=0.17-0.26). CONCLUSIONS: The results support the FMA and the WMFT-FAS are suitable to detect changes over time for patients after stroke rehabilitation. While simultaneously considering the responsiveness and validity attributes, the FMA may be a relatively sound measure of motor function for stroke patients based on our results. Further research based on a larger sample is needed to replicate the findings.

Effects of constraint-induced therapy versus bilateral arm training on motor performance, daily functions, and quality of life in stroke survivors.

BACKGROUND AND OBJECTIVE: This study investigated the relative effects of distributed constraint-induced therapy (CIT) and bilateral arm training (BAT) on motor performance, daily function, functional use of the affected arm, and quality of life in patients with hemiparetic stroke. METHODS: A total of 60 patients were randomized to distributed CIT, BAT, or a control intervention of less specific but active therapy. Each group received intensive training for 2 hours/day, 5 days/week, for 3 weeks. Pretreatment and posttreatment measures included the Fugl-Meyer Assessment (FMA), Functional Independence Measure (FIM), Motor Activity Log (MAL), and Stroke Impact Scale (SIS). The proximal and distal scores of FMA were used to examine separate upper limb (UL) elements of movement. RESULTS: The distributed CIT and BAT groups showed better performance in the overall and the distal part score of the FMA than the control group. The BAT group exhibited greater gains in the proximal part score of the FMA than the distributed CIT and control groups. Enhanced performance was found for the distributed CIT group in the MAL, the subtest of locomotion in the FIM, and certain domains of the SIS (eg, ADL/IADL). CONCLUSION: BAT may uniquely improve proximal UL motor impairment. In contrast, distributed CIT may produce greater functional gains for the affected UL in subjects with mild to moderate chronic hemiparesis.

Nosocomial outbreak of infection with multidrug-resistant Acinetobacter baumannii in a medical center in Taiwan.

OBJECTIVE: To investigate a nosocomial outbreak of infection with multidrug-resistant (MDR) Acinetobacter baumannii in the intensive care units at China Medical University Hospital in Taiwan. DESIGN: Prospective outbreak investigation. SETTING: Three intensive care units in a 2,000-bed university hospital in Taichung, Taiwan. METHODS: Thirty-eight stable patients in 3 intensive care units, all of whom had undergone an invasive procedure, were enrolled in our study. Ninety-four A. baumannii strains were isolated from the patients or the environment in the 3 intensive care units, during the period from January 1 through December 31, 2006. We characterized A. baumannii isolates by use of repetitive extragenic palindromic-polymerase chain reaction (REP-PCR) and random amplified polymorphic DNA (RAPD) fingerprinting. The clinical characteristics of the source patients and the environment were noted. RESULTS: All of the clinical isolates were determined to belong to the same epidemic strain of MDR A. baumannii by the use of antimicrobial susceptibility tests, REP-PCR, and RAPD fingerprinting. All patients involved in the infection outbreak had undergone an invasive procedure. The outbreak strain was also isolated from the environment and the equipment in the intensive care units. Moreover, an environmental survey of one of the intensive care units found that both the patients and the environment harbored the same outbreak strain. CONCLUSION: The outbreak strain of A. baumannii might have been transmitted among medical staff and administration equipment. Routine and aggressive environmental and equipment disinfection is essential for preventing recurrent outbreaks of nosocomial infection with MDR A. baumannii.

Significance of inflammatory cytokines in the progression of colorectal cancer.

BACKGROUND/AIMS: Circulating levels of inflammatory cytokines are associated with the disease status of cancer patients. Our purpose was to determine whether the profile of serum levels of interleukin-1 -2, -6, and -8, and tumor necrosis factor in patients with colorectal cancer correlated with tumor stages and survival. METHODOLOGY: Serum concentrations of individual cytokines in 164 colorectal cancer patients were determined before operation by enzyme-linked immunosorbent assay. The clinical significance of each serum cytokine was evaluated in relation to tumor progression and survival. RESULTS: Levels of interleukin-6 and interleukin-8 were significantly higher in patients than in controls. The serum concentrations of interleukin-2 and interleukin-6 were correlated with Dukes' stages. Only the levels of interleukin-6 were found to be associated with patient survival by univariate analysis. However, multivariate analysis did not identify interleukin-6 level as an independent factor of prognosis. CONCLUSIONS: Elevation of serum cytokines, such as interleukin-6, may be related to the development and progression of colorectal cancer. Interleukin-6 level is associated with the clinical outcome, but is not an effective prognostic predictor.

Serum interleukin-6 levels reflect the disease status of colorectal cancer.

BACKGROUND AND OBJECTIVES: Interleukin-6 (IL-6) has been shown to be associated with cancer development. However, its role in the progression of colorectal cancer has never been elucidated. Our intention was to investigate this role and identify its prognostic significance. METHODS: One hundred and sixty-four consecutive colorectal cancer patients, whose local lesions were resected, were selected. The preoperative serum IL-6 levels were measured and the relationships between the elevation of IL-6 and both the clinicopathological factors and prognosis of patients were investigated. RESULTS: Median IL-6 level was significantly higher in patients with colorectal cancer than in normal controls. High levels of serum IL-6 (>12 pg/ml) were correlated with larger tumor size, elevated serum CRP levels, and liver metastases (P < 0.05). IL-6 levels also increased in a stage-related manner (P < 0.01). Although serum IL-6 correlated with survival, it is not an independent prognostic indicator. CONCLUSIONS: Serum IL-6 levels correlated with disease status of colorectal cancer but could not be regarded as an independent predictor for prognosis.

Serum C-reactive protein correlates with survival in colorectal cancer patients but is not an independent prognostic indicator.

BACKGROUND: C-reactive protein (CRP) is an acute-phase protein synthesized in liver and up-regulated by pro-inflammatory cytokines, such as interleukin-6 (IL-6), interleukin-8 (IL-8) and tumour necrosis factor (TNF). Elevated CRP has been reported to be associated with reduced crude survival rates in patients with colorectal cancer. OBJECTIVE: To investigate the prognostic significance of preoperative serum CRP in relation to the disease-specific survival rate and expression of different cytokines. METHODS: One hundred and seventy-two consecutive patients with colorectal cancer, whose primary lesions were resected, were selected from April 1995 to December 1999. Preoperative serum CRP levels were measured, and the relationship between the elevation of CRP and clinicopathological factors was investigated. Prognostic significance was analysed by univariate and multivariate tests. RESULTS: One-third of patients had increased CRP levels, and this was associated with larger tumour size, lymph node or liver metastasis, and advanced Dukes' stage. Higher CRP levels were also related to the elevation of IL-6 and IL-8. The most important prognostic factor predicting survival was Dukes' stage (P < 0.001). Multivariate analysis indicated that CRP level is not an independent factor predicting survival. CONCLUSIONS: A preoperative elevation of serum CRP does not have the independent prognostic significance reported by earlier studies. Whether the elevated CRP can predict the development of cachexia or whether this association characterizes a pattern in tumour behaviour remains to be determined.

Association of proline-directed protein kinase FA with tumorigenesis, invasion, and poor prognosis of human colon carcinoma.

BACKGROUND: Initial studies revealed that the multisubstrate proline-directed protein kinase F(A) (PDPK F(A)) is overexpressed in various types of human carcinomas relative to normal controls. Suppression of overexpressed PDPK F(A) inhibits the growth of cancer cells, suggesting a role of this PDPK in human malignancy. In this study, we combine immunohistologic, molecular, cellular, animal, and clinicopathologic studies to demonstrate an essential and critical role of PDPK F(A) in progression and poor prognosis of human colon carcinoma. METHODS: The stable antisense clones of human colon carcinoma cells with specific suppression of PDPK F(A) were established for tumorigenesis and invasion studies. In immunohistologic and clinicopathologic studies, the expression and localization of PDPK F(A) were analyzed by immunohistochemical staining of the specimens obtained from human colon carcinoma patients with Dukes Stage B/C. RESULTS: Initial molecular and cellular studies revealed that the antisense clone of colon carcinoma cells (COLO-205) with specific suppression of PDPK F(A) dramatically lost capabilities of adhesion, chemotaxis, and invasion when compared with the parental or control-transfected colon carcinoma cells. This is the first indication of an association of overexpressed PDPK F(A) with colon carcinoma progression. In agreement with this notion, the in vivo study also revealed that the mice injected with the antisense clone with low-level PDPK F(A) only developed very small tumors (< 0.5 cm(3)) even after a 6-week observation. This is in contrast to the parental or control-transfected cells that developed large tumors (> 5 cm(3)) under identical conditions. Pathologic evaluation revealed invasion to the muscle layer in all tumors formed by the parental cells. In contrast, there was no sign of invasion in mice injected with the antisense clone, confirming an essential role of PDPK F(A) in colon carcinoma progression. Clinicopathologic study also revealed that PDPK F(A) is preferentially overexpressed in the invasive area of colon carcinomatous tissues and overexpression of PDPK F(A) is statistically and closely correlated with venous/lymphatic infiltration, lymph node metastasis, and poor prognosis of colon carcinoma patients with Dukes Stage B/C. CONCLUSIONS: The results demonstrate an essential and critical role of overexpressed PDPK F(A) in progression and poor prognosis of colon carcinoma patients. Suppression of overexpressed PDPK F(A) may provide a new powerful adjuvant approach to prevent human colon carcinoma progression and poor prognosis after surgery and chemotherapy.