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41.
Our previous work showed that a natural beta-(1-->3)-d-glucan schizophyllan (SPG) can form a stable complex with single-stranded oligonucleotides (ssODNs). When protein transduction peptides were attached to SPG and this modified SPG was complexed with ssODNs, the resultant complex could induce cellular transfection of the bound ODNs, without producing serious cytotoxicity. However, no technique was available to transfect double-stranded DNAs (dsDNA) or plasmid DNA using SPG. This paper presents a new approach to transfect dsDNA, showing preparation and transfection efficiency for a minimal-size gene having a loop-shaped poly(dA)(80) on both ends. This poly(dA) loops of dsDNA can form a complex with SPG. An siRNA-coding dsDNA with the poly(dA) loop was complexed with Tat-attached SPG to silence luciferase expression. When LTR-Luc-HeLa cells that can express luciferase under the control of the LTR promoter were exposed to this complex, the expression of luciferase was suppressed (i.e., RNAi effect was enhanced). Cytotoxicity studies showed that the Tat-SPG complex induced much less cell death compared to polyethylenimine, indicating that the proposed method caused less harm than the conventional method. The Tat-SPG/poly(dA) looped dsDNA complex had a structure similar to the viral genome in that the dsDNA ends were able to induce transfection and protection. The present work identifies the SPG and poly(dA) looped minimum-sized gene combination as a candidate for a non-toxic gene delivery system.  相似文献   
42.
To investigate the biological mechanism of gender identity disorder (GID), five candidate sex hormone-related genes, encoding androgen receptor (AR), estrogen receptors α (ERα) and β (ERβ), aromatase (CYP19), and progesterone receptor (PGR) were analyzed by a case–control association study. Subjects were 242 transsexuals (74 male-to-female patients (MTF) and 168 female-to-male patients (FTM)), and 275 healthy age- and geographical origin-matched controls (106 males and 169 females). The distributions of CAG repeat numbers in exon 1 of AR, TA repeat numbers in the promoter region of ERα, CA repeat numbers in intron 5 of ERβ, TTTA repeat numbers in intron 4 of CYP19, and six polymorphisms (rs2008112, rs508653, V660L, H770H, rs572698 and PROGINS) of PGR were analyzed. No significant difference in allelic or genotypic distribution of any gene examined was found between MTFs and control males or between FTMs and control females. The present findings do not provide any evidence that genetic variants of sex hormone-related genes confer individual susceptibility to MTF or FTM transsexualism.  相似文献   
43.
OBJECTIVE: Patients with atopic eczema (AE) often complain of sleep disturbance. Melatonin is involved in sleep, and the levels of blood melatonin in patients with AE are decreased in comparison to healthy subjects. However, the levels of breast-milk melatonin had only been reported in healthy subjects. Laughter increased natural killer cell activity in blood and free radical-scavenging capacity in saliva in healthy subjects. Thus, the effect of laughter on the levels of breast-milk melatonin was studied in mothers with AE. Moreover, the effect of feeding with breast milk after laughter on allergic responses in infants was studied. METHODS: Forty-eight infants aged 5-6 months were enrolled. All of the infants had AE and were allergic to latex and house dust mite (HDM). Half (n=24) of the mothers of these infants were patients with AE, while another 24 mothers were healthy subjects. The mothers viewed either an 87-min humorous DVD (Modern Times, featuring Charlie Chaplin) or an 87-min nonhumorous weather information DVD at 2000 h. After viewing, breast milk was collected sequentially from 2200, 2400, 0200, 0400 to 0600 h. The levels of breast-milk melatonin were measured. In addition, skin wheal responses to HDM and histamine were studied in infants. RESULTS: Laughter caused by viewing a humorous DVD increased the levels of breast-milk melatonin in both mothers with AE and healthy mothers. In addition, allergic responses to latex and HDM of infants were reduced by feeding with breast milk after laughter of mothers with AE or of healthy mothers. CONCLUSION: Laughter increased the levels of breast-milk melatonin in both mothers with AE and healthy mothers, and feeding infants with increased levels of melatonin-containing milk reduced allergic responses in infants. Thus, laughter of mothers may be helpful in the treatment of infants with AE.  相似文献   
44.
To evaluate the present status of prostate cancer in patients 75 years of age or older, we reviewed clinical characteristics of prostate cancer in patients from the Kitamurayama Hospital. The number of symptomatic advanced cases was greater in patients > or = 75 years old compared with patients < or = 74 years old. However, no significant difference in cause-specific survival rate was found between the two groups. In the cases examined, the difference in biological characteristics between groups did not affect the prognosis. On the other hand, for patients > or = 75 years old, improvement of urinary retention was low, and the incidence of adverse drug responses to endocrine therapy, such as dementia and thrombosis, was high. We recognize the necessity of a comprehensive medical plan that attaches importance to quality of life and safety for the treatment of patients over 75 years old with prostate cancer.  相似文献   
45.
46.

Purpose

Methamphetamine is the most widespread illegally used stimulant in the United States. Previously published case reports and series suggest a potential association between methamphetamine exposure and cardiomyopathy. The objective of this study is to demonstrate an association between methamphetamine use and cardiomyopathy.

Subject and Methods

Case-control study based on chart review of discharges from a tertiary care medical center from January 2001 to June 2004. Patients were ≤45 years old. Cases included patients with a discharge diagnosis of either cardiomyopathy or heart failure. Controls included hospitalized patients who had an echocardiographic assessment of left ventricular function with ejection fraction ≥55% and no wall motion abnormalities.

Results

One hundred and seven cases and 114 controls were identified. Both groups had similar gender distribution, length of hospital stay, rates of health insurance, prevalence of coronary artery disease, diabetes mellitus, hypertension, cigarette smoking, alcohol abuse, and marijuana and cocaine use. Cases were older than controls (mean age: 38 vs 35 years; P=.008), had higher body mass index (BMI) (mean BMI: 37 vs 30 kg/m2; P<.001), and higher prevalence of renal failure (13% vs 4.4%; P=.03). Methamphetamine users had a 3.7-fold increased odds ratio [95% confidence interval, 1.8-7.8] for cardiomyopathy, adjusting for age, body mass index, and renal failure.

Conclusions

Methamphetamine use was associated with cardiomyopathy in young patients.  相似文献   
47.
Objective. The usefulness of 18F-fluoro-2-deoxyglucose positron emission tomography (18FDG-PET), whose high rate of FDG accumulation indicates high metabolism and malignant potential, has already been reported. The aims of this study were to evaluate the malignancy of primary gastrointestinal stromal tumour (GIST) in the stomach by 18FDG-PET and to correlate the FDG uptake values with known risk factors as determined by histology after EUS-guided fine needle aspiration (EUS-FNA) or endoscopic biopsy. Material and Methods. Of 29 patients with histologically proven GI-mesenchymal tumours, 21 with gastric GISTs underwent 18FDG-PET. Tumour size, mitotic index, Ki-67 labelling index (LI) and cellularity of the tumour tissue were compared with the standardized uptake value (SUV) of FDG. Results. Strong correlations were found between the SUV of FDG and EUS size, and mitotic index of EUS-FNA specimens (tumour size versus SUV, p=0.004, r=0.542; number of mitotic cells versus SUV, p=0.0078; n=21). Moreover, we examined the association between SUV and risk categories based on EUS-FNA findings using ROC curves. The cut-off values of FDG SUV were 2.2, 4.2 and 6.5 for the very low-, low-, intermediate- and high-risk groups, respectively. Conclusions. 18FDG-PET may be used to assess malignancy of GISTs. This image modality helps us determine the management strategy for these patients and complements the information on the biological behaviour and cellular proliferation of the tumours.  相似文献   
48.
49.
BACKGROUND: Bone and mineral metabolism is abnormal in most chronic haemodialysis patients and is associated with a high mortality risk. Because of possible pathogenic links between anaemia and intact parathyroid hormone (iPTH), the present study evaluated associations of mineral metabolism indicators with haemoglobin (Hb). METHODS: Data were collected from 317 facilities (12 089 haemodialysis patients) in Australia, Belgium, Canada, France, Germany, Italy, Japan, New Zealand, Spain, Sweden, the United Kingdom and the United States by the Dialysis Outcomes and Practice Patterns Study (DOPPS). The major outcome studied was probability of haemodialysis patients having a target Hb, per guidelines, of >/=11 g/dl at baseline. Major predictor variables were patient characteristics and laboratory markers of mineral metabolism: albumin-corrected serum calcium (calcium(Alb)), serum phosphorus (PO(4)) and iPTH. Analyses were adjusted for demographics, 15 comorbidity classes, baseline laboratory values, body mass index, years on dialysis, erythropoietin dose, vitamin D and catheter use, cause of end-stage renal disease and country. RESULTS: The adjusted odds ratio (AOR) of having Hb >/=11 g/dl was significantly higher (P<0.0001) in patients with higher calcium(Alb) (AOR = 1.32 per 1 mg/dl), higher PO(4) (AOR = 1.08 per 1 mg/dl) and lower iPTH (AOR = 0.96 per 100 pg/ml). Furthermore, 4 month intrapatient changes in Hb concentration were significantly (P<0.0001) related to 4 month changes in calcium(Alb) (0.17 g/dl Hb rise per 1 mg/dl higher calcium(Alb)) and PO(4) (0.11 g/dl Hb rise per 1 mg/dl higher PO(4)). Mean weekly recombinant human erythropoietin (rHuEpo) doses were higher for patients with high PO(4) or iPTH levels, but lower for patients with calcium(Alb) >9.5 mg/dl, after patient mix and Hb concentration adjustments. CONCLUSIONS: The results of this study indicate that higher serum calcium(Alb) and PO(4) levels are each independently associated with better anaemia control. This relationship is independent of vitamin D use, PTH levels and prescribed rHuEpo dose. Despite this benefit of better anaemia control at higher serum calcium(Alb) and PO(4) concentrations, lower calcium and PO(4) levels, as recommended by the K/DOQI guidelines, should still serve as the long-term goal for HD patients in order to minimize tissue calcification and mortality risk.  相似文献   
50.
Candida albicans is both a commensal and a pathogen in the oral mucosa. Previous studies have indicated that epithelial cell-associated carbohydrate moiety can inhibit C. albicans growth. In the present study, the mechanisms by which epithelial cells inhibit Candida growth were studied by examining the effect of hyaluronan (HA). A coculture of C. albicans and KB cells or COS-7 cells inhibited in vitro growth of the fungus by 50-87% at an effector-to-target (E:T) ratio of 80:1. Removing extracellular HA by hyaluronidase caused a significant decrease in the anti-Candida activity of the cells. In addition anti-Candida activity was observed at 1 micro g/ml HA (2000 kDa). The antifungal activity of extracellular HA was further studied by transiently transfecting COS-7 cells with human HSA1, HSA2, or HSA3 in order to produce high levels of extracellular HA. All of the transfectants inhibited C. albicans growth in vitro by 51-65% compared to 38% inhibition by the vector control (P<0.05). These results suggest that the anti-Candida activity of epithelial-cells is mediated by extracellular HA.  相似文献   
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