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71.
HIV-1 Immunogen is a gp120-depleted whole killed virus vaccine candidate formulated with Incomplete Freund's Adjuvant (HIV-IFA). We evaluated in a mouse model the immunogenicity of HIV-IFA by itself and when combined with HYB2055, an immunomodulatory oligonucleotide consisting of a novel DNA structure and synthetic CpR immunostimulatory motif, as an adjuvant. C57/BL6 mice were immunized with HIV-IFA alone or combined with HYB2055. Mice treated with HYB2055 or with PBS were used as controls. Compared to HIV-IFA alone, immunization with HIV-IFA and HYB2055 combination elicited strong production of HIV- and p24-specific IFNgamma, RANTES, MIP 1alpha, and MIP 1beta, as well as high titers of HIV- and p24-specific antibodies. Inclusion of HYB2055 also reduced levels of IL-5 produced by HIV-IFA alone. HYB2055 enhances the immunogenicity of HIV-IFA and shifts responses towards a type 1 cytokine profile. The immune enhancing effects of HYB2055 adjuvant were dose-dependent. These findings warrant clinical evaluation of the HIV-1 immunogen/HYB2055 candidate as a therapeutic vaccine for HIV-1 infected patients.  相似文献   
72.
A validated model of disease progression in IgA nephropathy   总被引:4,自引:0,他引:4  
BACKGROUND: IgA nephropathy (IgAN) is the most common primary glomerulonephritis in the general population. There is accumulating evidence that immunosuppressive treatment is efficacious in IgAN. However, it is critical to define appropriate indicators for this therapy especially in the wake of potentially deleterious side effects to immunosuppressives. METHODS: This study retrospectively reviewed IgAN cases collected since 1981 to identify clinical and/or histological parameters for disease progression; 310 patients with biopsy proven IgAN, diagnosed from January 1981 to March 2004, were included. RESULTS: We defined a clinical prognostic index (CPI) using multivariate analysis, which incorporated these clinical/ histological parameters. Semiquantitative scores were assigned as follows: 2 points if creatinine (Cr) was >1.4 mg/dL, 1 point if proteinuria was >1 g/24 hr, 1 point if a patient was affected by hypertension, and 1 point if a patient was older than 30 yrs. Dividing our population into two groups (scores 0-2 = low CPI group; scores 3-5 = high CPI group), we demonstrated a significantly different 10-yr renal survival rate; in the low CPI group, renal survival since time of biopsy at 10 yrs was 91.7%; in the high CPI group the renal survival at 10 yrs was 35%. We validated the CPI in an independent sample from Verona (validation group) and demonstrated similar results for the CPI. CONCLUSIONS: The CPI is convenient to use for defining the risk of disease progression.  相似文献   
73.
HCV‐RNA assessment during therapy with Direct‐Acting Antiviral (DAA) regimens still relies on assays requiring blood collection and transport to a specialised laboratory, which may compromise linkage to care. GeneXpert‐HCV Viral Load (GXHVL) (Cepheid) is a plasma‐based assay used at point of care (POC) with a sensitivity of ≤10 IU/mL, and, results available within 2 hours. Fifty‐nine consecutive HCV‐patients ready for DAAs treatment were enrolled. HCV‐RNA was simultaneously tested using Roche TaqMan RT‐PCR (venous blood sample) and GXHVL (capillary blood collected by fingerstick), at baseline (BL), week 4 (W4) of therapy, end of therapy (EOT) and week 12 of follow‐up (W12FU). Both assays demonstrated undetectable HCV‐RNA in all patients at EOT and identified the single case of HCV‐relapse at W12FU. GXHVL used as a point‐of‐care assay in the outpatient setting provides results fully comparable to the laboratory‐based test. Its excellent performance and ease of use suggest its adoption in non‐specialist settings where simplicity of care is paramount to implement HCV eradication campaigns.  相似文献   
74.
In Streptococcus pyogenes, efflux-mediated erythromycin resistance is associated with the mef gene, represented mostly by mef(A), although a small portion of strains carry different mef subclasses. We characterized the composite genetic elements, including mef subclasses other than mef(A), associated with other resistance genes in S. pyogenes isolates. Determination of the genetic elements was performed by PCR mapping. The strains carrying mosaic mef(A/E), in which the 5' region was identical to mef(A) and the 3' region was identical to mef(E), also carried tet(O). The two genes were found enclosed in an element similar to S. pyogenes prophage Φm46.1, designated the Φm46.1-like element. In S. pyogenes strains carrying mef(E) and tet(M), mef(E) was included in a typical mega element, and in some strains, it was physically associated with tet(M) in the composite element Tn2009. S. pyogenes strains carrying mef(I) also carried catQ; the two genes were linked in a fragment representing a portion of the 5216IQ complex of Streptococcus pneumoniae, designated the defective IQ element. In the only isolate carrying a novel mef gene, this was associated with catQ and tet(M) in a genetic element similar to the 5216IQ complex of S. pneumoniae (5216IQ-like complex), suggesting that the novel mef is in fact a variant of mef(I). This study demonstrates that the composite elements containing mef are shared between S. pyogenes and S. pneumoniae and suggests that it is important to distinguish the mef subclass on the basis of the genetic element containing it.  相似文献   
75.
Intake of 3,4-methylenedioxymethamphetamine (MDMA, ecstasy) in humans leads to marked behavioral alterations. In a recent paper, we demonstrated that chronic MDMA intake produces a latent hippocampal hyperexcitability that parallels a reduced threshold for limbic seizures and a slowing of electroencephalographic activity. These phenomena suggest an alteration in hippocampal function. So far, only a few studies have focused on the hippocampal formation as a potential target for the effects induced by MDMA. In this study we sought to evaluate whether the intrinsic cells of the hippocampus might be modified chronically by ecstasy intake. In particular, we examined whether administration of MDMA, at doses producing hippocampal hyperexcitability also produces rearrangements of DNA strands measured by the comet assay. We found that MDMA, at very low doses, comparable with those self-administered by humans, produces acute oxidative stress and DNA single and double-strand breaks, which persist together with long-lasting metabolic changes in the hippocampal formation. These persisting effects are accompanied by behavioral sensitization, reduced seizure threshold and long-lasting slowing of electroencephalographic activity, and hyperexcitability of the hippocampus, without affecting the basal ganglia. The present data indicate that the intake of very low doses of MDMA, comparable to those consumed by humans, produces selective hippocampal alterations which may underlie cognitive impairment and seizure susceptibility.  相似文献   
76.
Down syndrome (DS) is generally considered as an "atheroma-free model". In this preliminary study, we investigated homocysteine, folate and Vitamin B(12) levels in 13 DS patients (male, average age 60 years) and 20 age-matched individuals. We also studied lipid fractions, and polymorphisms for Cystothionine beta-synthase (CBS), 5,10-methyl-tetrahydro-folate reductase (MTHFR) and apolipoprotein E (Apo-E) genes. However, DS patients with the MTHFR TT genotype showed an increased of plasma homocysteine (tHcy). Our results indicate that this group of "healthy old" Down syndrome patients, although showing some classical biochemical risk factors for atherosclerosis, did not suffer clinical cardiovascular alterations.  相似文献   
77.

Purpose

Oxidative stress has been found to play a key role in several diseases, that range from cancer to neurodegenerative disorders. Besides traditional anti-oxidant agents, in recent years much attention has been focused on nanotechnological solutions, including cerium oxide nanoparticles (nanoceria).

Methods

Thanks to its extraordinary catalytic properties, nanoceria mimics the activity of superoxide dismutase and of catalase, therefore acting as a reactive oxygen species (ROS) scavenger in many biological contexts. In this paper, we report on nanoceria interactions with PC12 cell line, that represents a valuable model for many features of central dopaminergic neurons.

Results

Nanoceria confirmed a strong anti-ROS action but, most interestingly, also showed beneficial effects on both cell differentiation and dopamine production.

Conclusions

Even if deeper examinations will be necessary in order to better clarify the mechanisms at the base of the documented effects, nanoceria demonstrated a significant potential as pharmacological agent in the treatment of neurological disorders.  相似文献   
78.
The presence of both a uterovaginal septum and imperforate hymen is described in a young patient presenting with ongoing chronic pelvic pain and a double pyocolpos. Ultrasound and magnetic resonance imaging scans were performed. The patient underwent laparoscopic adesiolysis, hymenotomy with drainage of 200 mL of pus, and excision of a complete longitudinal vaginal septum. Over the past 5 years of regular follow-up examinations, the patient has always reported regular menstrual cycles and an absence of pelvic pain.  相似文献   
79.
Kainic acid (KA) induced seizures provokes an extensive neuronal degeneration initiated by c-Jun N-terminal kinases (JNK) as central mediators of excitotoxicity. However, the actions of their individual isoforms in cellular organelles including mitochondria remain to be elucidated. Here, we have studied the activation of JNK1, JNK2 and JNK3 and their activators, mitogen-activated protein kinase kinase (MKK) 4/7, in brain mitochondria, cytosolic and nuclear fractions after KA seizures. In the mitochondrial fraction, KA significantly increased the presence of JNK1, JNK3 and MKK4 and stimulated their phosphorylation i.e. activation. The pro-apoptotic proteins, Bim and Bax were induced and, consequently, the ratio Bcl-2-Bax decreased. These changes were paralleled by the release of cytochrome c and cleavage of poly(ADP-ribose)-polymerase (PARP).The JNK peptide inhibitor, D-JNKI-1 (XG-102) reversed these pathological events in the mitochondria and almost completely abolished cytochrome c release and PARP cleavage. Importantly, JNK3, but not JNK1 or JNK2, was associated with Bim in mitochondria and D-JNKI-1 prevented the formation of this apoptotic complex.Apart from of the attenuation of c-Jun phosphorylation in the nucleus, D-JNKI-1 did not affect the level of JNK3 isoform in the nuclear and cytosolic fractions. These findings provide novel insights into the mode of action of individual JNK isoforms in cell organelles and points to the JNK3 pool in mitochondria as a target of the JNK inhibitor D-JNKI-1 to confer neuroprotection.  相似文献   
80.

Objective

The purpose of this study was to evaluate changes in subthalamic nucleus (STN) neuronal activity in Parkinson’s disease (PD) patients during deep brain stimulation (DBS) surgery under general anesthesia, and to compare these data with those recorded in the same subjects during previous surgery under local anesthesia.

Methods

Five patients with advanced PD, who had previously undergone bilateral STN-DBS under local anesthesia, underwent re-implantation under general anesthesia (with an anesthetic protocol based on the intravenous infusion of remifentanyl and ketamine) owing to surgical device complications. The microelectrode recording (MER) data obtained were analyzed by an off-line spike-sorting software. Neurophysiological data (number of spikes detected, mean firing rate, pause index and burst index) obtained under local and general anesthesia were then evaluated and compared by means of statistical analysis.

Results

We found no statistically significant difference between the first and second surgical procedures in any of the neurophysiological parameters analyzed.

Conclusions

Bilateral STN-DBS for advanced PD with MER guidance is possible and reliable under a ketamine-based anesthetic protocol.

Significance

General anesthesia can be proposed for those patients who do not accept an “awake surgery” for clinical reasons, such as excessive fear, poor cooperation or severe “off”-medication effects.  相似文献   
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