Animals ; Cardiovascular Diseases ; metabolism ; Humans ; Hydrogen Sulfide ; metabolism ; Hypertension ; metabolism ; Signal Transduction ; physiology

Rap1 is a small G protein belonging to the RAS superfamily. Rap1 signalling has effects on cell growth, cell proliferation and involves in regulation of the mitogen activated protein (MAP) kinase or ERK (extracellular signal regulated kinase) cascade. Rap1 will directly activate ERK through B-Raf. B-Raf is a member of Raf family, and presents in neuronal and hematopoietic cells. Oncogenic mutations of gene RAS are most frequent and detected in 20% - 30% of human leukemias and 10% - 15% of MDS cases. The review summarizes the regulatory function of Rap1 in development of hematopoietic cells and effect of Rap1 in hematologic malignancies.
Hematologic Neoplasms ; genetics ; metabolism ; Humans ; Signal Transduction ; rap1 GTP-Binding Proteins ; genetics ; metabolism

Previous study on the gene expression profile of human MDS by using microarray discovered that transcription of RAP1GAP was up-regulated, which was confirmed by quantitative RT-PCR in expanding cohort of MDS patients. This study was pourposed to investigate the expression of RAP1GAP in human MDS and its clinical relevance. The expression of RAP1GAP in bone marrow cells of 19 MDS patients was detected by flow cytometry and was compared with that in patients with non-malignant blood diseases and acute leukemias, meanwhile the relevance between expression level of RAP1GAP and hemoglobin, leukocytes, platelets, blasts percentage in bone marrow cells and IPSS score was analyzed. The results indicated that the expression level of RAP1GAp in MDS patients significantly increased as compared with patients with non-malignant blood diseases or AML (8.42 +/- 8.37% vs 2.97 +/- 4.75% or 2.26 +/- 4.24%). Among MDS patients, the expression level of RAP1GAP in MDS-RA was significantly higher than that in MDS-RAEB (11.64 +/- 9.07% vs 4.37 +/- 4.65%). However, no definitive correlation of expression level with above-mentioned clinical parameters was found in detected patients with DMS. In conclusion, the expression of RAP1GAP in MDS patients obviously increases, the relationship between expression level of RAP1GAP and laboratory hematological parameter and IPSS score does not be confirmed. The role played by RAP1GAP expression in the pathogenesis of MDS and its clinical significance during progression of MDS towards AML deserves further studies.
Adult ; Aged ; Aged, 80 and over ; Female ; Flow Cytometry ; GTPase-Activating Proteins ; genetics ; metabolism ; Gene Expression Profiling ; Humans ; Male ; Middle Aged ; Myelodysplastic Syndromes ; genetics ; metabolism

Aims: Piper nigrum L. (black pepper) is an economically important commodity plant in Malaysia, which generated RM 200.95 million from pepper export in the year of 2018. However, the increase in pepper production is restricted by diseases. Fusarium wilt is one of the major diseases of P. nigrum L. The objectives for this study were to isolate Fusarium spp. associated with Fusarium wilt of P. nigrum L. from selected pepper farms in the northwestern region of Sarawak and to characterize the Fusarium spp. isolated morphologically and molecularly. Methodology and results: Fusarium spp. were isolated from diseased root samples. The pathogen was grown on potato dextrose agar (PDA) under dark condition at circa (ca.) 25 °C for morphological characterisation. Molecular characterisation was done by using internal transcribed spacer (ITS). Phylogenetic tree was constructed to study the genetic relationship of the isolates. Fusarium solani, F. oxysporum, F. proliferatum were the three Fusarium species identified. There were variations in morphological characters observed between and among the species, including the colony form, margin, elevation, surface appearance and pigmentation. No distinctive morphological characteristic was specific to a location. In addition, growth rate, macroconidia sporulation rate, and microconidia sporulation rate of the isolates were not correlated. In molecular phylogeny, the three Fusarium species were separated into three distinct clades representing the three identified species. The genetic relatedness between isolates within each species was depicted in the tree. Conclusion, significance and impact of study Variations were observed among isolates in this study based on morphological and molecular characterization. This study would contribute information on the variations of Fusarium spp. associated with Fusarium wilt of P. nigrum L. from the northwestern region of Sarawak.
Fusarium ; Fusariosis ; Piper nigrum