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71.
1. The plasma brain natriuretic peptide (BNP) concentration is elevated in patients with essential hypertension and normal systolic function. This may be related to left ventricular hypertrophy or diastolic dysfunction, both of which commonly occur in hypertension. 2. Echocardiography was performed on 32 patients with newly diagnosed untreated mild-to-moderate hypertension (19 men, 13 women; mean±SD age 51±15 years; diastolic blood pressure 99±12mmHg; systolic blood pressur. 153.2±18.0 mmHg; plasma creatinine 86±15 μmol/L; creatinine clearance 92.2±20.5 mL/min; left ventricular mass index 116±28 g/m2; left ventricular ejection fraction 66±9%). A 15 mL peripheral venous blood sample was obtained at the time of echocardiography for radioimmunoassay of BNP. 3. Sixteen patients had abnormal Doppler transmitral flow (E/A rati. < 1) and a higher median plasma BNP concentration compared with those patients with E/A ≥1 (12.9 vs 5.9 pmol/L, respectively; P = 0.006). The plasma BNP level correlated significantly with E/A ratio (r = -0.50; P = 0.035). Multivariate analysis showed that the E/A ratio is related to plasma BNP, independent of age and blood pressure. 4. Our results suggest that the plasma BNP level is influenced by diastolic dysfunction. Further studies are needed to determine whether assay of plasma BNP helps to identify patients with diastolic dysfunction.  相似文献   
72.
1对象和方法1.1 对象 本组共160例,女性146例,男性14例.72例为双侧单睑,88例为双上睑皮肤松驰,平均年龄37(18~56)岁.1.2 方法 嘱患者微闭眼下视,用美篮在睑缘上方6mm~8mm处画一条平行于睑缘的切口线,内中1/3交界处为最...  相似文献   
73.
74.
The expression of the anti-apoptotic molecules Bcl-2 and transforming growth factor-beta 1 is known to confer protective effects on the cerebral ischemia-reperfusion injury.The current study investigated the expression levels of Bcl-2 and transforming growth factor-beta 1 in response to multiple pre-ischemia electro-acupuncture at acupoints Zusanli(ST36)and Fengchi(GB20) stimulation.Rats were divided into five groups:uninjured,control,non-acupoint,GB20 and ST36. Rats in the non-acupoint,GB20 and ST36 groups received 30 minutes(3 times or 18 times)of electro-acupuncture stimulation before experimental cerebral ischemia was induced.Bcl-2 and transforming growth factor-beta 1 were found to be significantly increased in the ST36 groups with either 3 or 18 electro-acupuncture treatments(P<0.05).The production was higher with 18 electro-acupuncture treatments in the ST36 groups(P<0.05).In the GB20 groups,significant increase was only observed in transforming growth factor-beta 1 with 18 electro-acupuncture treatments(P<0.05).No significant elevation of the level of transforming growth factor-beta 1 was observed in the non-acupoint groups.However,the production of Bcl-2 increased with 18 treatments in the non-acupoint groups(P<0.05).The data suggest that multiple pre-ischemia electro-acupuncture at ST36 was effective in conferring neuroprotective effect on the brain by means of upregulation of Bcl-2 and transforming growth factor-beta 1 and the effect was increase with the number of treatment.  相似文献   
75.

Introduction

Given their relative simplicity of manufacture and ability to be injected repeatedly, vaccines in a protein format are attractive for breast and other cancers. However, soluble human epidermal growth factor receptor (HER2)/neu protein as a vaccine has not been immunogenic. When protein is directly targeted to antigen uptake receptors, such as DEC205 (DEC), efficient processing and presentation of antigen take place. The aim of this study was to determine the immunogenicity of a HER2 protein vaccine that directly targets to DEC+ dendritic cells (DCs) in a mouse breast cancer model.

Methods

We genetically engineered the HER2 extracellular domain into a monoclonal antibody specific for DEC (DEC-HER2). Mice of various genetic backgrounds were immunized with DEC-HER2 in combination with DC maturation stimuli (poly IC ± CD40 Ab). Vaccine-induced T cell immunity was determined by analyzing the ability of CD4+/CD8+ T cell to produce interferon (IFN)-gamma and proliferate upon antigen rechallenge. Sera were assessed for the presence of antigen specific antibody (Ab). For vaccine efficacy, FVB/N mice were immunized with DEC-HER2 in combination with poly IC and protection against neu-expressing mammary tumors was assessed. Protection mechanisms and tumor-specific T cell responses were also evaluated.

Results

We demonstrate that DEC-HER2 fusion mAb, but not Ctrl Ig-HER2, elicits strong, broad and multifunctional CD4+ T cell immunity, CD8+ T cell responses, and humoral immunity specific for HER2 antigen. Cross-reactivity to rat neu protein was also observed. Importantly, mice xeno-primed with DEC-HER2 were protected from a neu-expressing mammary tumor challenge. Both CD4+ and CD8+ T cells mediated the tumor protection. Robust anti-tumor T cell immunity was detected in tumor protected mice.

Conclusions

Immunization of mice with HER2 protein vaccine targeting DEC+ DCs in vivo induced high levels of T- and B-cell immunity. Non-targeted HER2 protein was poorly immunogenic for CD4+ and CD8+ T cells. This vaccination approach provided long-term survival benefit for mice challenged with neu-expressing tumor following as little as 2.7 ??g of HER2 protein incorporated in the vaccine. Vaccine-induced CD4+ and CD8+ T cells were both essential for tumor protection. This immunization strategy demonstrates great potential towards the development of vaccines for breast cancer patients.  相似文献   
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77.
Background : In the past, practitioners have used distance and/or near visual acuity (VA) to calculate required magnification for low vision aids. Magnification was usually under‐estimated when compared with the final magnification prescribed. Recent studies have emphasised the importance of acuity reserve in determining the required magnification for optimum reading rate. Two different approaches have been proposed for the appropriate acuity reserve to use in calculating magnification. These are a fixed acuity reserve of 0.3 log unit or an individual determination of optimum acuity reserve. The aim of this study was to investigate the magnification and reading rates with low vision aids selected by the two methods. Methods : Nineteen low vision subjects with age‐related macular degeneration (AMD) who were experienced magnifier‐users were recruited. Reading rates and near VA with low vision aids determined by the fixed and individual acuity reserve methods were compared with the same measures made with the subjects' own magnifiers. Results : There were no significant differences in reading rate and near VA measured with low vision aids selected by either the fixed or individual acuity reserve methods or the subjects' own magnifiers. Reading rate with low vision aids was not significantly different from reading rate for large print with conventional near additions. Thus, for experienced users, magnifiers do not cause reduced reading rate. Conclusions : The fixed acuity reserve method is simple to apply as only near VA and print size of the target reading task are required. For the individual acuity reserve method, reading rates at different print sizes need to be measured. We recommend the use of a fixed acuity reserve (0.3 log unit) for the calculation of required magnification for low vision patients. If near VA or reading rate are not satisfactory with the magnification calculated by this method, individual assessment of required acuity reserve is necessary.  相似文献   
78.
We have investigated whether a protective immune response occurred in mice infected with a virulent cloned strain of Plasmodium chabaudi. Animals inoculated intravenously with 10(7) parasitized erythrocytes (PE) showed an exponentially increasing parasitaemia and died by day 6 of the infection, presenting a pronounced anaemia. Smaller inocula produced a longer pre-patent period but did not change the lethal course of infection, since mice injected with 100 parasites died on day 12. When anaemia was compensated for by red blood cell (RBC) transfusion, infected mice recovered and thereafter exhibited a strong immunity, comparable to that of mice immunized by a drug-controlled infection. The immune response was P. chabaudi specific, as the mice were fully susceptible to a challenge by P. yoelii. Three transfusions of 5 x 10(9) RBC per mouse at 2-day intervals were necessary before all the animals were able to control the infection. Transfusion of a larger number of RBC resulted in a lower anaemia and a delay in reticulocytaemia but, paradoxically, the expression of the immune response was delayed. Three transfusions of 1.2 x 10(10) RBC enabled three out of eight mice to survive the infection, while six transfusions enabled all the mice to survive. The data suggest that parasitized immature RBC could play an important role in triggering the protective immune response.  相似文献   
79.
80.

Background and Purpose

SU4312, a potent and selective inhibitor of VEGF receptor-2 (VEGFR-2), has been designed to treat cancer. Recent studies have suggested that SU4312 can also be useful in treating neurodegenerative disorders. In this study, we assessed neuroprotection by SU4312 against 1-methyl-4-phenylpyridinium ion (MPP+)-induced neurotoxicity and further explored the underlying mechanisms.

Experimental Approach

MPP+-treated neurons and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated zebrafish were used to study neuroprotection by SU4312. NOS activity was assayed in vitro to examine direct interactions between SU4312 and NOS isoforms.

Key Results

SU4312 unexpectedly prevented MPP+-induced neuronal apoptosis in vitro and decreased MPTP-induced loss of dopaminergic neurons, reduced expression of mRNA for tyrosine hydroxylase and impaired swimming behaviour in zebrafish. In contrast, PTK787/ZK222584, a well-studied VEGFR-2 inhibitor, failed to prevent neurotoxicity, suggesting that the neuroprotective actions of SU4312 were independent of its anti-angiogenic action. Furthermore, SU4312 exhibited non-competitive inhibition of purified neuronal NOS (nNOS) with an IC50 value of 19.0 μM but showed little or no effects on inducible and endothelial NOS. Molecular docking simulations suggested an interaction between SU4312 and the haem group within the active centre of nNOS.

Conclusions and Implication

SU4312 exhibited neuroprotection against MPP+ at least partly via selective and direct inhibition of nNOS. Because SU4312 could reach the brain in rats, our study also offered a support for further development of SU4312 to treat neurodegenerative disorders, particularly those associated with NO-mediated neurotoxicity.  相似文献   
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