251 research outputs found
A diagnostic support tool for lumbar spinal stenosis: a self-administered, self-reported history questionnaire
<p>Abstract</p> <p>Background</p> <p>There is no validated gold-standard diagnostic support tool for LSS, and therefore an accurate diagnosis depends on clinical assessment. Assessment of the diagnostic value of the history of the patient requires an evaluation of the differences and overlap of symptoms of the radicular and cauda equina types; however, no tool is available for evaluation of the LSS category. We attempted to develop a self-administered, self-reported history questionnaire as a diagnostic support tool for LSS using a clinical epidemiological approach. The aim of the present study was to use this tool to assess the diagnostic value of the history of the patient for categorization of LSS.</p> <p>Methods</p> <p>The initial derivation study included 137 patients with LSS and 97 with lumbar disc herniation who successfully recovered following surgical treatment. The LSS patients were categorized into radicular and cauda equina types based on history, physical examinations, and MRI. Predictive factors for overlapping symptoms between the two types and for cauda equina symptoms in LSS were derived by univariate analysis. A self-administered, self-reported history questionnaire (SSHQ) was developed based on these findings. A prospective derivation study was then performed in a series of 115 patients with LSS who completed the SSHQ before surgery. All these patients recovered following surgical treatment. The sensitivity of the SSHQ was calculated and clinical prediction rules for LSS were developed. A validation study was subsequently performed on 250 outpatients who complained of lower back pain with or without leg symptoms. The sensitivity and specificity of the SSHQ were calculated, and the test-retest reliability over two weeks was investigated in 217 patients whose symptoms remained unchanged.</p> <p>Results</p> <p>The key predictive factors for overlapping symptoms between the two categories of LSS were age > 50, lower-extremity pain or numbness, increased pain when walking, increased pain when standing, and relief of symptoms on bending forward (odds ratio ≥ 2, p < 0.05). The key predictive factors for cauda equina type symptoms were numbness around the buttocks, walking almost causes urination, a burning sensation around the buttocks, numbness in the soles of both feet, numbness in both legs, and numbness without pain (odds ratio ≥ 2, p < 0.05). The sensitivity and specificity of the SSHQ were 84% and 78%, respectively, in the validation data set. The area under the receiver operating characteristic curve was 0.797 in the derivation set and 0.782 in the validation data set. In the test-retest analysis, the intraclass correlation coefficient for the first and second tests was 85%.</p> <p>Conclusion</p> <p>A new self-administered, self-reported history questionnaire was developed successfully as a diagnostic support tool for LSS.</p
Micro-Welding of Copper Plate by Frequency Doubled Diode Pumped Pulsed Nd:YAG Laser
AbstractA pulsed laser of 532nm wavelength with ms range pulse duration was newly developed by second harmonic generation of diode pumped pulsed Nd:YAG laser. High electro-optical conversion efficiency more than 13% could be achieved, and 1.5kW peak power green laser pulse was put in optical fiber of 100μm in diameter. In micro- welding of 1.0mm thickness copper plate, a keyhole welding was successfully performed by 1.0kW peak power at spot diameter less than 200μm. The frequency doubled pulsed laser improved the processing efficiency of copper welding, and narrow and deep weld bead was stably obtained
Signal Changes in the Brain on Susceptibility-Weighted Imaging Under Reduced Cerebral Blood Flow: A Preliminary Study
OBJECTIVES: To reveal the characteristics of susceptibility‐weighted imaging (SWI) under low cerebral blood flow (CBF) induced by hyperventilation (HV). MATERIALS AND METHODS: This study was approved by the institutional review board. Informed consent was obtained. Six healthy volunteers (5 men, 1 woman; mean age, 29 years; range, 24‐33 years) underwent SWI and arterial spin labeling perfusion imaging under normal ventilation (NV) and HV at 3.0 T. Regions of interest (ROIs) were placed on gray matter (GM) and white matter (WM) of the frontal lobe (FL) and occipital lobe (OL). Intensities of ROIs were compared between NV and HV. Contrast of veins compared with adjacent cerebral parenchyma (CV) was also compared between NV and HV. RESULTS: CBF during HV (CBFHV) was decreased compared with CBF during NV (CBFNV) (29.1 ± 4.6%). FL‐GMHV and OL‐GMHV showed significant signal decreases compared with FL‐GMNV and OL‐GMNV, respectively (P= .018, .017). CVHV was significantly increased compared with CVNV (164.1 ± 29.9%) (P= .00019). CONCLUSIONS: SWI sensitively reflects HV‐induced decreases in CBF. The present results might assist in the interpretation of SWI in clinical practice, since CBF decreases might also influence signal changes on SWI
Methanol stimulates the colony-formation rate in a human hepatoma cell line (HLE).
<P>Effects of methanol on colony-formation of human hepatoma cells were investigated. Among five human hepatoma cell lines (Hep G2, HLE, HuH-6, HuH-7, and PLC/PRF/5), only HLE cells showed enhanced colony formation due to methanol. The effective concentrations of methanol were around 1%. The enhancement occurred in a greater degree when the cells were seeded in the culture medium containing methanol than when methanol was added 24h after the cells were seeded. Methanol itself, however, did not enhance the cell proliferation.</p
Symmetrical Skin Lesions on the Gluteal Region in a Patient with Anti-Laminin-332 Mucous Membrane Pemphigoid
Mucous membrane pemphigoid (MMP), previously
called cicatricial pemphigoid, is a rare subepidermal
immunobullous disorder that primarily affects
the mucous membranes (1,2). MMP is divided
into two major subtypes, anti-BP180-type MMP and
anti-laminin-332 (previously called laminin 5 or epiligrin)
MMP. Anti-laminin-332 MMP is known to be
associated with malignant tumors (3), which may
cause overexpression of autoantibodies and induce
autoimmunity to laminin-332 (4). MMP primarily affects
the mucous membranes, and widespread skin
lesions are rare. In MMP, circumscribed skin lesions
have been previously reported as occurring on the
head, neck, and upper trunk (5). We report a case of
anti-laminin-332 MMP presenting with symmetrical
skin lesions characteristic of MMP on the weightbearing
areas of the gluteal regio
Qualitative Analysis of the Psychosocial Adaptation Process in Children with Chronic Kidney Disease : Toward Effective Support During Transition from Childhood to Adulthood
【Background】 Pediatric chronic renal disease only shows abnormal values in a urinalysis in the initial stage, and subjective signs and symptoms are rare. If adolescents with chronic renal disease face a disease crisis combined with the usual developmental crisis, this may cause psychosocial maladaptation. We analyzed psychosocial adaptation in Japanese children with chronic renal disease in order to identify factors influencing healthy adaptation. 【Methods】 Ten children and adult patients with chronic kidney disease attending Tottori University Hospital, Japan in 2016 participated in a semi-structured interview (a modified version of the grounded theory approach) comprising questions about episodes since disease onset and thoughts/feelings at onset. 【Results】 Twenty-four concepts extracted from the data were sorted into 5 categories. These concepts and categories were expanded on an orthogonal axis with time and self-esteem in order to establish an adaptation model for children with chronic kidney disease. Category names are as follows. (Cat. 1: Emotional impact on being informed of disease, Cat. 2: Social challenges of treatment and resulting identity diffusion, Cat. 3: Emotional conflict on school return, Cat. 4: Resilience and related factors, Cat. 5: Re-establishment of identity). 【Conclusion】 Since pediatric chronic renal disease has few manifestations, it is difficult for patients to accept. Children facing a chronic disease crisis plus adolescent developmental crisis may show identity diffusion. In order for children to re-establish their identity and adapt to society, factors supporting resilience are important. Key factors include school life, interactions with friends, counseling by adult mentors and family acceptance. Healthcare professionals need to provide age-appropriate information on renal disease and support patients
Pharmacokinetic analysis of new synthetic antimalarial N-251
Background
With the emergence and growing number of drug-resistant Plasmodium falciparum, a new drug for malaria control must be urgently developed. The new antimalarial synthetic compound N-251 was recently discovered. As an endoperoxide structure in the body, the compound shows high antimalarial activity and curative effects. We performed a pharmacokinetic (PK) analysis of N-251 under various conditions using mice to understand the inhibitory effect of N-251 in parasite-infected mice.
Results
PK study of N-251 after intravenous and oral administration in mice showed plasma concentration of N-251 was decreased drastically by intravenous route. Cmax was reached in 2 h after oral administration of N-251, and the level decreased to a level similar to that obtained after intravenous administration. The area under the curves (AUCs) of the plasma concentration of N-251 increased dose-proportionally in both administrations, and bioavailability (F) was approximately 23%. Additionally, Tmax, Cmax, AUC, and F increased in fasted mice compared to normal-fed mice after the administration of N-251, indicating the influence of diet on the absorption kinetics of N-251. Furthermore, in parasite-infected fasted mice, the plasma concentration-time profile of N-251 was similar to that in normal-fasted mice. Based on the PK parameters of single oral administration of N-251, we investigated the effect of multiple oral doses of N-251 (68 mg/kg three times per day for 2 days) in normal-fed mice. The plasma concentration of N-251 was between 10 and 1000 ng/mL. The simulation curve calculated based on the PK parameters obtained from the single-dose study well described the plasma concentrations after multiple oral dosing, indicating that N-251 did not accumulate in the mice. Multiple oral administrations of N-251 in mice were required to completely eliminate parasites without accumulation of N-251.
Conclusions
N-251 has been selected as a potent antimalarial candidate. We found that N-251 showed short half-life in plasma, and AUCs increased proportionally to dose. With multiple doses of N-251, the plasma level of N-251 was greater than 10 ng/mL in normal-fed mice, and accumulation of N-251 was not observed; however, multiple treatments with N-251 are required for the complete cure of parasite-infected mice. Determining the appropriate dosage was an important step in the clinical applications of N-251
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