The prevalence of LRRK2 Gly2385Arg variant in Chinese Han population with Parkinson's disease.

We conducted a case-control study to determine the prevalence of the LRRK2 Gly2385Arg variant in patients with Parkinson's disease in Han population in mainland China. Heterozygous LRRK2 Gly2385Arg variant was identified in 14 of 235 patients with Parkinson's disease (5.69%), but not in 214 unrelated healthy controls. Multivariate analysis indicated the frequency of Gly2385Arg variant in the female patients with early age at onset is higher than their male counterparts. The founder haplotype analysis showed the variant carriers shared the same founder. Clinically, the LRRK2 Gly2385Arg carriers presented with classical Parkinson's disease symptoms. Our study indicates that the LRRK2 Gly2385Arg variant is a potential ethnic-specific genetic risk factor of Parkinson's disease within Chinese Han ethnicity.     

Enhancement of blood-brain barrier permeability to sodium fluorescein by stimulation of µ opioid receptors in mice

Summary The effects of opioids on the permeability of the blood-brain barrier (BBB) were examined in mice with sodium fluorescein as an indicator of the permeability. The brain was perfused with saline 30 min after injection of sodium fluorescein (40 mg/kg, i. v.) and examined by fluorometry. Morphine hydrochloride (0.3–10 mg/kg, s. c.) markedly increased the brain level of sodium fluorescein dose-dependently without influencing the plasma level, when administered 20 min before sodium fluorescein injection. Intracerebroventricularly (i. c. v.) injected morphine hydrochloride (0.5 and 1.0 Erg) increased the brain sodium fluorescein level. Buprenorphine (0.1 and 0.5 mg/kg, s. c.) was also effective. However, pentazocine, ethylketazocine, U-50488H and SKF-10047 had no significant influence. The i.c.v. administration of [D-Ala², McPhe⁴, Gly(ol)⁵]enkephalin (0.1 g) and [D-Ala², D-Leu⁵]enkephalin (0.5 g) but not of [D-Thr², Leu⁵]enkephalin-Thr increased the brain level of sodium fluorescein significantly. A small dose of naloxone (i. p.) significantly inhibited the effects of morphine, buprenorphine, [D-Ala², McPhe⁴, Gly(ol)⁵]enkephalin and [D-Ala³, D-Leu⁵]enkephalin. ICI-174864 co-administered i. c. v. with [D-Ala², D-Leu⁵]enkephalin was ineffective in antagonizing the effect of the latter. These findings suggest that the stimulation of µ opioid receptors results in an increase in BBB permeability to sodium fluorescein. Send offprint requests to K. Saeki     

Ara h 8, a Bet v 1-homologous allergen from peanut, is a major allergen in patients with combined birch pollen and peanut allergy

BACKGROUND: We recently described patients with soybean allergy mainly mediated by cross-reactivity to birch pollen allergens. A majority of those patients were reported to have peanut allergy. OBJECTIVE: We sought to study the occurrence of peanut allergy in patients allergic to birch pollen and characterized the Bet v 1-homologous peanut allergen Ara h 8. METHODS: Recombinant Ara h 8 was cloned with degenerated primers and expressed in Escherichia coli. Nine Swiss and 11 Dutch patients with peanut and birch pollen allergy and a positive double-blind, placebo-controlled food challenge result to peanut were investigated for IgE reactivity to birch pollen and purified peanut allergens and cross-reactivity between birch and peanut. Ara h 8 stability against digestion and roasting was assessed by means of RAST inhibition. The IgE cross-linking potency of Ara h 8 was tested on the basis of basophil histamine release. RESULTS: During double-blind, placebo-controlled food challenge, all patients experienced symptoms in the oral cavity, progressing to more severe symptoms in 40% of patients. CAP-FEIA detected recombinant (r) Ara h 8-specific IgE in 85%. IgE binding to Ara h 8 was inhibited by Bet v 1 in peanut extract immunoblotting and in RAST inhibition. In EAST inhibition recombinant rAra h 8 inhibited IgE binding to peanut in 4 of 7 tested patient sera. Antipeanut response was dominated by Ara h 8 in 12 of 17 tested patients. Furthermore, our results demonstrate a low stability of Ara h 8 to roasting and no stability to gastric digestion. Basophil histamine release with rAra h 8 was more than 20% in 5 of 7 tested sera. CONCLUSIONS: Peanut allergy might be mediated in a subgroup of our patients by means of cross-reaction of Bet v 1 with the homologous peanut allergen Ara h 8.     

Epidermal growth factor and insulin short‐term increase hPepT1‐mediated glycylsarcosine uptake in Caco‐2 cells

Aims: Little is known about the physiological regulation of the human intestinal di/tri‐peptide transporter, hPepT1. In the present study we evaluated the effects of epidermal growth factor (EGF) and insulin on hPepT1‐mediated dipeptide uptake in the intestinal cell line Caco‐2. Methods: Caco‐2 cells were grown on filters for 23–27 days. Apical dipeptide uptake was measured using [¹⁴C]glycylsarcosine([¹⁴C]Gly‐Sar). HPepT1 mRNA levels were investigated using RT‐PCR, cytosolic pH was determined using the pH‐sensitive fluorescent probe BCECF. Results: Basolateral application of EGF increased [¹⁴C]Gly‐Sar uptake with an ED₅₀ value of 0.77 ± 0.25 ng mL^?1 (n = 3?6) and a maximal stimulation of 33 ± 2% (n = 3?6). Insulin stimulated [¹⁴C]Gly‐Sar uptake with an ED₅₀ value of 3.5 ± 2.0 ng mL^?1 (n = 3?6) and a maximal stimulation of approximately 18% (n = 3?6). Gly‐Sar uptake followed simple Michaelis‐Menten kinetics. K_m in control cells was 0.98 ± 0.11 mM (n = 8) and V_max was 1.86 ± 0.07 nmol cm^?2 min^?1 (n = 8). In monolayers treated with 200 ng mL^?1 of EGF, K_m was 1.11 ± 0.05 mM (n = 5) and V_max was 2.79 ± 0.05 nmol cm^?2 min^?1 (n = 5). In monolayers treated with 50 ng mL^?1 insulin, K_m was 1.03 ± 0.08 mM and V_max was 2.19 ± 0.06 nmol cm^?2 min^?1 (n = 5). Kinetic data thus indicates an increase in the number of active transporters, following stimulation. The incrased Gly‐Sar uptake was not accompanied by changes in hPepT1 mRNA, nor by measurable changes in cytosolic pH. Conclusions: Short‐term stimulation with EGF and insulin caused an increase in hPepT1‐mediated uptake of Gly‐Sar in Caco‐2 cell monolayers, which could not be accounted for by changes in hPepT1 mRNA or proton‐motive driving force.     

A novel p.Gly417Valfs*12 mutation in the MTTP gene causing abetalipoproteinemia: Presentation of the first patient in Mexico and analysis of the previously reported cases

BackgroundOur aims were to describe the first Mexican patient with abetalipoproteinemia and to perform a comparative analysis of biochemical, clinical, and genetic characteristics of 100 cases reported in the literature.MethodsWe performed biochemical and molecular screenings in a Mexican girl with extremely low lipid levels and in her family. Further, we integrated and evaluated the characteristics of the cases with abetalipoproteinemia described in the literature.ResultsOur patient is a six‐year‐old girl who presented vomiting, chronic diarrhea, failure to thrive, malabsorption, acanthocytosis, anemia, transaminases elevation, and extremely low lipid levels. MTTP gene sequencing revealed homozygosity for a novel mutation p.Gly417Valfs*12 (G deletion c.1250). With the analysis of the reported cases, 60 clinical features (14 classical and 46 non‐classical) were observed, being the most common acanthocytosis (57.5%), malabsorption (43.7%), and diarrhea (42.5%); 48.8% of the patients presented only classic clinical features, while the remaining 51.2% developed secondary effects due to a fat‐soluble vitamin deficiency. An odds ratio analysis disclosed that patients diagnosed after 10 years of age have an increased risk for presenting clinical complications (OR = 18.0; 95% CI 6.0‐54.1, p < 0.0001). A great diversity of mutations in MTTP has been observed (n = 76, being the most common p.G865X and p.N139_E140) and some of them with possible residual activity.ConclusionThe first Mexican patient with abetalipoproteinemia presents a novel MTTP mutation p.Gly417Valfs*12. Three factors that could modulate the phenotype in abetalipoproteinemia were identified: age at diagnosis, treatment, and the causal mutation.     

Calcium deposition in photocrosslinked poly(Pro‐Hyp‐Gly) hydrogels encapsulated rat bone marrow stromal cells

Reproducing the features of the extracellular matrix is important for fabricating three‐dimensional (3D) scaffolds for tissue regeneration. A collagen‐like polypeptide, poly(Pro‐Hyp‐Gly), is a promising material for 3D scaffolds because of its excellent physical properties, biocompatibility, and biodegradability. In this paper, we present a novel photocrosslinked poly(Pro‐Hyp‐Gly) hydrogel as a 3D scaffold for simultaneous rat bone marrow stromal cell (rBMSC) encapsulation. The hydrogels were fabricated using visible‐light photocrosslinking at various concentrations of methacrylated poly(Pro‐Hyp‐Gly) (20–50 mg/ml) and irradiation times (3 or 5 min). The results show that the rBMSCs encapsulated in the hydrogels survived 7 days of incubation. Calcium deposition on the encapsulated rBMSCs was assessed with scanning electron microscope observation, Alizarin Red S, and von Kossa staining. The most strongly stained area was observed in the hydrogel formed with 30 mg/ml of methacrylated poly(Pro‐Hyp‐Gly) with 5‐min irradiation. These findings demonstrate that poly(Pro‐Hyp‐Gly) hydrogels support rBMSC viability and differentiation, as well as demonstrating the feasibility of using poly(Pro‐Hyp‐Gly) hydrogels as a cytocompatible, biodegradable 3D scaffold for tissue regeneration.     

甘草甜素等对黄曲霉毒素B1致大鼠肝癌作用的影响

应用黄曲霉毒素B_1(AFB_1)致大鼠肝癌作用的短期体内实验模型,研究两种治疗慢性乙肝的中药制剂甘草甜素和水飞蓟素及可食植物柑果之果皮、果汁对AFB_1致肝癌作用的影响。发现甘草甜素具有明显抑制AFB_1诱发肝癌前病变的作用。文中对甘草甜素的抑制机理进行了讨论。     

Association between the MnSOD Ala-9Val polymorphism and development of schizophrenia and abnormal involuntary movements in the Xhosa population

Reactive oxygen species (ROS)-mediated damage has been hypothesized to play a role in the development and poor outcome of schizophrenia, as well as the development of neuroleptic-induced abnormal involuntary movements. Recently, the functional polymorphism (Ala-9Val) in the manganese superoxide dismutase (MnSOD) gene (part of the antioxidant defense mechanism) was found to be associated with schizophrenia in a Turkish population. This study was aimed at replicating this finding in a Xhosa population. In addition, the role of Ala-9Val in abnormal involuntary movement and tardive dyskinesia development in the Xhosa population was also investigated. The schizophrenic patient group (n=286) and a healthy control group (n=243) were genotyped for the Ala-9Val polymorphism using heteroduplex-single stranded conformational polymorphism (HEX-SSCP) analysis. No significant difference in genotype or allele frequency could be observed between the schizophrenia and control group (P=0.294 and P=0.528 respectively). In addition no association could be found between the polymorphism and symptom severity (SANS and SAPS). The Xhosa schizophrenia patient group with abnormal involuntary movements (n=54) and a subgroup with tardive dyskinesia (n=30) was found to significantly differ in Ala-9Val genotype frequency (P=0.008 and P=0.011 respectively) compared to the Xhosa schizophrenia patient group without abnormal involuntary movements (n=204). However, no significant difference was found for the allele frequencies (P=0.955 and P=0.161). Further, using ANCOVA no association was found between AIMS score and genotype in the group with abnormal involuntary movements (P=0.1234). However, in the patient group with tardive dyskinesia an association was observed between genotype and AIMS score (P=0.0365). These results do not support a major role of the MnSOD Ala-9Val polymorphism in the development of schizophrenia or symptom severity in the Xhosa population. Yet it seems to be involved in the development of abnormal involuntary movements and tardive dyskinesia and may even modulate the severity of tardive dyskinesia.     

Association of the DRD2 and DRD3 polymorphisms with response to pramipexole in Parkinson’s disease patients

Objective  To evaluate the impact of the DRD2 TaqIA and DRD3 Ser9Gly polymorphisms on the efficacy of pramipexole in treating patients with Parkinson’s disease (PD). Methods  Thirty patients with PD prospectively received pramipexole 0.25 mg three times daily for 2 months. Unified Parkinson Disease Rating Scale (UPDRS) assessments were conducted at baseline and 2 months after treatment initiation. Improvement by 20% or more in the total score on the UPDRS was considered to indicate responsiveness. The PCR–restriction fragment length polymorphism analysis was used to analyze the DRD2 Taq1A and DRD3 Ser9Gly genotype. Results  The DRD2 Taq1A allele frequencies were A141.7 (A1) and 58.3% (A2), and the DRD3 Ser9Gly allele frequencies were 68.3 (Ser) and 31.7% (Gly). When the subjects were grouped by the DRD3 Ser9Gly polymorphism, the response rates for pramipexole treatment were significantly higher in the Ser/Ser group (60%) than in the group containing the Gly allele (13%). There was a significant association between the DRD3 Ser9Gly polymorphism and response rate to pramipexole in PD patients (P = 0.024). When the subjects were grouped by the DRD2 Taq1A polymorphism, there were no significant differences among the three Taq1A genotypes. Conclusions  DRD3 Ser9Gly polymorphisms are significantly associated with the therapeutic efficacy of pramipexole in Chinese patients with PD. A large-scale and multi-dose group study in patients with PD is necessary for evaluating the impact of the genetic polymorphisms of the dopamine receptor on the therapeutic effects of pramipexole.