L-glutamic acid-g-poly hydroxyethyl methacrylate nanoparticles: acute and sub-acute toxicity and biodistribution potential in mice

The aim of this safety study in mice was to determine in vivo toxicity and biodistribution potential of a single and multiple doses of L-glutamic acid-g-p(HEMA) polymeric nanoparticles as a drug delivery system. The single dose did not cause any lethal effect, and its acute oral LD₅₀ was >2.000 mg/kg body weight (bw). Multiple doses (25, 50, or 100 mg/kg bw) given over 28 days resulted in no significant differences in body and relative organ weights compared to control. These results are supported by biochemical and histological findings. Moreover, nanoparticle exposure did not result in statistically significant differences in micronucleus counts in bone marrow cells compared to control. Nanoparticle distribution was time-dependent, and they reached the organs and even bone marrow by hour 6, as established by ex vivo imaging with the IVIS^® spectrum imaging system. In conclusion, L-glutamic acid-g-p(HEMA) polymeric nanoparticles appear biocompatible and have a potential use as a drug delivery system.KEY WORDS: biocompatibility, blood biochemistry, genotoxicity, histology, in vivo toxicity, micronucleus test, polymers     

Antibody-based immunotherapies for Parkinsonian syndromes

<正>what is the rationale for immunotherapies in Parkinsonian syndromes(PS)? PS are neurodegenerative diseases which are clinically characterized by a hypokinetic phenotype in combination with additional motor and non-motor symptoms. One major patholog-     

慢性应激诱导DPP-4表达及对脂肪炎症和代谢的影响

目的　分析慢性应激诱导脂肪二肽基肽酶-4（DPP-4）表达及对脂肪炎症和糖代谢的影响。 方法　雄性SPF级小鼠20只随机分慢性应激（Stress）组和正常对照（Control）组。Stress组小鼠每天在自制式束缚器中限制活动2 h，实验持续14 d。采用免疫组化方法检测巨噬细胞表面标志物（CD11b）在脂肪中的表达，实时定量PCR法检测脂肪组织中DPP-4、细胞因子（Adiponectin、MCP-1、IL-6、TNF-α）及糖代谢（IRS-1、GLUT-4）等指标的mRNA的相对表达量；ELISA法检测DPP-4酶活性及GLP-1浓度。 结果　Stress小鼠腹部白色脂肪组织（WAT）与Control组相比显著的退缩及其重量显著降低（P<0.001）。Stress组WAT出现大量的单核细胞、中性粒细胞浸润反应和炎症性改变；Stress显著降低Adiponectin的表达，并显著增高MCP-1、IL-6、TNF-α的mRNA表达及其血液中的浓度（P<0.001）；Stress组WAT组织中DPP-4 mRNA表达及其血液中的活性显著增高，而GLP-1血液中的浓度显著降低（P<0.001）；Stress组WAT组织中IRS-1及GLUT-4的mRNA水平显著低于Control组（P<0.001）。 结论　慢性应激诱导脂肪DPP-4异常表达，进而引起脂肪炎症和糖代谢异常等反应。     

Description of Leprosy Classification at Baseline among Patients Enrolled at the Uniform Multidrug Therapy Clinical Trial for Leprosy Patients in Brazil

The uniform multidrug therapy clinical trial, Brazil (U-MDT/CT-BR), database was used to describe and report the performance of available tools to classify 830 leprosy patients as paucibacillary (PB) and multibacillary (MB) at baseline. In a modified Ridley and Jopling (R&J) classification, considering clinical features, histopathological results of skin biopsies and the slit-skin smear bacterial load results were used as the gold standard method for classification. Anti-phenolic glycolipid-I (PGL-I) serology by ML Flow test, the slit skin smear bacterial load, and the number of skin lesions were evaluated. Considering the R&J classification system as gold standard, ML Flow tests correctly allocated 70% patients in the PB group and 87% in the MB group. The classification based on counting the number of skin lesions correctly allocated 46% PB patients and 99% MB leprosy cases. Slit skin smears properly classified 91% and 97% of PB and MB patients, respectively. Based on U-MDT/CT-BR results, classification of leprosy patients for treatment purposes is unnecessary because it does not impact clinical and laboratories outcomes. In this context, the identification of new biomarkers to detect patients at a higher risk to develop leprosy reactions or relapse remains an important research challenge.     

Variation in the Susceptibility of Drosophila to Different Entomopathogenic Nematodes

Entomopathogenic nematodes (EPNs) in the genera Heterorhabditis and Steinernema are lethal parasites of insects that are of interest as models for understanding parasite-host interactions and as biocontrol agents for insect pests. EPNs harbor a bacterial endosymbiont in their gut that assists in insect killing. EPNs are capable of infecting and killing a wide range of insects, yet how the nematodes and their bacterial endosymbionts interact with the insect immune system is poorly understood. Here, we develop a versatile model system for understanding the insect immune response to parasitic nematode infection that consists of seven species of EPNs as model parasites and five species of Drosophila fruit flies as model hosts. We show that the EPN Steinernema carpocapsae, which is widely used for insect control, is capable of infecting and killing D. melanogaster larvae. S. carpocapsae is associated with the bacterium Xenorhabdus nematophila, and we show that X. nematophila induces expression of a subset of antimicrobial peptide genes and suppresses the melanization response to the nematode. We further show that EPNs vary in their virulence toward D. melanogaster and that Drosophila species vary in their susceptibilities to EPN infection. Differences in virulence among different EPN-host combinations result from differences in both rates of infection and rates of postinfection survival. Our results establish a powerful model system for understanding mechanisms of host-parasite interactions and the insect immune response to parasitic nematode infection.     

Post-Lyme disease syndrome

About 10% of patients with Lyme disease continue to experience musculoskeletal pain and cognitive dysfunction after recommended antibiotic treatment. This condition is called post-Lyme disease syndrome (PLDS) or post-treatment Lyme disease syndrome. These two terms are used interchangeably. The pathogenesis of PLDS has been controversial. The hypothesis that patients with PLDS may harbor hidden reservoirs of Borrelia burgdorferi after their initial antibiotic treatment is difficult to accept. The prospective, double-blind studies contradict this point of view. Also, recently published research applying xenodiagnosis to PLDS supports the opinion that PLDS most likely has an autoimmune background. Lengthy courses of antibiotics are not justified in patients with PLDS because of the lack of benefit, and they are fraught with hazards. Most patients with PLDS recover from persistent symptoms with time. However, it can take months before they feel completely well.