Genetic Variants of LRRK2 in Taiwanese Parkinson’s Disease

Genetic variants of leucine-rich repeat kinase 2 (LRRK2) were reported to alter the risk for Parkinson’s disease (PD). However, the genetic spectrum of LRRK2 variants has not been clearly disclosed yet in Taiwanese population. Herein, we sequenced LRRK2 coding region in 70 Taiwanese early onset PD patients (age at onset ≤ 50), and found six amino acid-changing single nucleotide polymorphisms (SNPs, N551K, R1398H, R1628P, S1647T, G2385R and M2397T), one reported (R1441H) and 2 novel missense (R767H and S885N) mutations. We examined the frequency of identified LRRK2 variants by genotyping 573 Taiwanese patients with PD and 503 age-matched control subjects. The results showed that PD patients demonstrated a higher frequency of G2385R A allele (4.6%) than control subjects (2.1%; odds ratio = 2.27, 95% confidence interval: 1.38–3.88, P = 0.0017). Fewer PD patients (27.7%) carried the 1647T-2397T haplotype as compared with the control subjects (33.0%; odds ratio = 0.80, 95% confidence interval: 0.65–0.97, P = 0.0215). However, the frequency of 1647T-2385R-2397T haplotype (4.3%) in PD patients was still higher than in control subjects (1.9%, odds ratio: 2.15, 95% confidence interval: 1.27–3.78, P = 0.0058). While no additional subject was found to carry R767H and R1441H, one more patient was observed to carry the S885N variant. Our results indicate a robust risk association regarding G2385R and a new possible protective haplotype (1647T-2397T). Gene-environmental interaction and a larger cohort study are warranted to validate our findings. Additionally, two new missense mutations (R767H and S885N) regarding LRRK2 in PD patients were identified. Functional studies are needed to elucidate the effects of these LRRK2 variants on protein function.     

Evidence for a novel bursting mechanism in rodent trigeminal neurons.

We investigated bursting behavior in rodent trigeminal neurons. The essential mechanisms operating in the biological systems were determined based on testable predictions of mathematical models. Bursting activity in trigeminal motoneurons is consistent with a traditional mechanism employing a region of negative slope resistance in the steady-state current-voltage relationship (Smith, T. G. 1975. Nature. 253:450-452). However, the bursting dynamics of trigeminal interneurons is inconsistent with the traditional mechanisms, and is far more effectively explained by a new model of bursting that exploits the unique stability properties associated with spike threshold (Baer, S. M., T. Erneux, and J. Rinzel. 1989. SIAM J. Appl. Math. 49:55-71).     

Kinetic resolution of N-protected amino acid esters in organic solvents catalyzed by a stable industrial alkaline protease

Summary An industrial alkaline protease Alcalase has been found to be very stable in organic solvents and usable as a catalyst for resolution of N-protected amino acids, in both aqueous solution and organic solvent with high yield and optical purity. Only the L-amino acid ester has been hydrolysed.Abbreviation Cbz- carbobenzyloxy- - OMe methyl ester - Hop homophenylalanine - Nol norleucine - Aba -amino butyric acid - Nov norvaline - Fug furylglycine     

Sweet pepper ferredoxin-like protein ( pflp) gene as a novel selection marker for orchid transformation

A novel method for selection of transgenic plants utilizing the sweet pepper ( Capsicum annuum L.) ferredoxin-like protein ( pflp) gene as selection marker and Erwinia carotovora as the selection agent has been developed. An expression vector containing a pflp cDNA driven by a cauliflower mosaic virus 35S promoter was successfully transformed into protocorm-like bodies of Oncidium orchid by Agrobacterium tumefaciens and particle bombardment, respectively. Erwinia carotovora was used as a selection agent to screen transformants, thereby obtaining transgenic plants without the use of an antibiotic selection agent. A total of 32 independent transgenic orchid lines were obtained, out of which 9 transgenic lines (beta-glucuronidase positive) were randomly selected and confirmed by Southern and northern blot analyses. The transgenic orchid plants showed enhanced resistance to E. carotovora, even when the entire plant was challenged with the pathogen. Our results suggest the novel use of the pflp gene as a resistance selection marker in plant genetic engineering strategies. In the future, the use of the pflp gene as a selection marker may facilitate the use of smaller gene constructs due to removal of bulky antibiotic selection and reporter genes. These constructs can then be used to incorporate additional genes of choice.     

Three-dimensional cytomorphology in fine needle aspiration biopsy of parathyroid lesions

OBJECTIVE: To elucidate three-dimensional (3-D) cytomorphology in fine needle aspiration biopsy (FNAB) of parathyroid lesions. STUDY DESIGN: Ultrasound-guided FNAB was performed on parathyroid lesions from 10 patients with hyperparathyroidism. The aspirates were stained and observed under a light microscope (LM). The aspirates were also fixed, dehydrated, critical point dried, spattered with gold ions and observed with a scanning electron microscope (SEM). Findings under SEM were correlated with the appearances under LM as well as with serum parathyroid hormone (PTH) concentrations. RESULTS: Under LM, nine cases displayed isokaryosis and one case, anisokaryosis. These appearances corresponded to isocytosis or anisocytosis under SEM. Under SEM, 3-D cytomorphology of parathyroid lesions displayed isocytotic, scattered cells in five cases, uniform cellular arrangements in four cases and anisocytotic, scattered cells in one case. The cell surface was rather smooth in five cases. The other five cases had significant granules on the cell surfaces; these all had serum PTH concentrations > or = 268 pg/mL. CONCLUSION: 3-D cytomorphology in FNAB of parathyroid lesions was a rather smooth cell surface in cases with low serum PTH and a granular cell surface in cases with significantly increased serum PTH. These characteristics and the absence of microvilli might be helpful in the differential diagnosis between parathyroid and follicular thyroid lesions.     

Tumour necrosis factor-alpha enhances bradykinin-induced signal transduction via activation of Ras/Raf/MEK/MAPK in canine tracheal smooth muscle cells

Inhalation of tumour necrosis factor-alpha (TNF-alpha) induced a bronchial hyperreactivity to contractile agonists. However, the mechanisms of TNF-alpha involved in the pathogenesis of bronchial hyperreactivity were not completely understood. Therefore, we investigated the effect of TNF-alpha on bradykinin (BK)-induced inositol phosphate (IP) accumulation and Ca(2+) mobilization, and up-regulation of BK receptor density in canine cultured tracheal smooth muscle cells (TSMCs). Pretreatment of TSMCs with TNF-alpha potentiated BK-induced IP accumulation and Ca(2+) mobilization. However, there was no effect on the IP response induced by endothelin-1 (ET-1), 5-hydroxytryptamine (5-HT), and carbachol. Pretreatment with PDGF B-chain homodimer (PDGF-BB) also enhanced BK-induced IP response. These enhancements induced by TNF-alpha and PDGF-BB might be due to an increase in BK B(2) receptor density (B(max)), since [3H]BK binding to TSMCs was inhibited by the B(2) selective agonist and antagonist, BK and Hoe 140, but not by the B(1) selective reagents. The enhancing effects of TNF-alpha and PDGF-BB were attenuated by PD98059 (an inhibitor of activation of MAPK kinase, MEK) and cycloheximide (an inhibitor of protein synthesis), suggesting that TNF-alpha may share a common signalling pathway with PDGF-BB via protein(s) synthesis in TSMCs. Furthermore, overexpression of dominant negative mutants, H-Ras-15A and Raf-N4, significantly suppressed p42/p44 mitogen-activated protein kinase (MAPK) activation induced by TNF-alpha and PDGF-BB and attenuated the effect of TNF-alpha on BK-induced IP response, indicating that Ras and Raf may be required for activation of these kinases. These results suggest that the augmentation of BK-induced responses produced by TNF-alpha might be, at least in part, mediated through activation of Ras/Raf/MEK/MAPK pathway in TSMCs.