In silico approaches in the identification of Cryptococcus neoformans chemoreceptors

Cryptococcus neoformans, a pathogenic, yeast-like fungus, typically forms biofilms on medical devices that prevents the efficient penetration of antifungal drugs. As quorum sensing (QS)-related chemoreceptors play a crucial role in the pathogenesis of Cryptococcus neoformans particularly in biofilm formation, studying them would enable a clearer understanding on the host-pathogen interaction. However, information regarding C. neoformans QS-related chemoreceptors such as the encoding DNA sequences, protein structures and the binding ligands remain unknown till today. Here, we provide information to facilitate researchers to comprehend the basic views on gene homology and its various applications in the identification of novel chemoreceptors in microorganism especially the novel QS-related chemoreceptors for future use.Keywords: Cryptococcus neoformans, homology-based transfer, quorum sensing, chemoreceptor

Professional pathway for civil aviation authority of Malaysia (CAAM) aircraft maintenance license holder registered at BEM

This paper proposes a professional pathway for Civil Aviation Authority of Malaysia (CAAM) Aircraft Maintenance License Holder (AML) currently registered with the Board of Engineers Malaysia (BEM). It carries out a study on how the professional pathway enhances the AML holder professional development and complement CAAM functions. It highlights the importance of professional development and the importance of compliance of code of conduct as an aircraft maintenance engineering professional. The aircraft maintenance engineering professionals covered the holder of aircraft maintenance license non type rated category B1 and B2 registered as engineering technician, category B1 and B2 with type rating who is registered as engineering technologist and category C with type rating who is registered as graduate engineer at Board of Engineers Malaysia. Literatures were reviewed and reference to existing professional pathway practices of Engineering Council, United Kingdom through its licensed society such as Royal Aeronautical Society, United Kingdom was an example analyzed. This paper resulted in the proposal of professional development pathway for the CAAM AML holders who are registered at BEM various categories. This paper also clarifies that airworthiness certification of the CAAM AML holders are governed by CAAM. Professional registration of the CAAM AML holder at BEM ensures AML holders complies with the professional code of conduct and ethics as registered engineering professional such as professional engineer (P.Eng). It also ensure continuous professional development as BEM registered engineering personnel. The outcome shows that AML holder professional registration at BEM enhances the AML holder professional development and complement CAAM functions in achieving the Malaysian aerospace blueprint 2030 effectively

Diel osmorespiration rhythms of juvenile marble goby (Oxyeleotris marmorata)

Oxyeleotris marmorata is an ambush predator. It is known for slow growth rate and high market demand. Farming of O. marmorata still remains a challenge. In order to establish a proper feeding practice to stimulate growth, knowledge of its metabolic processes and cost should be examined. Therefore, this study was designed to investigate the diel osmorespiration rhythms of O. marmorata in response to feeding challenge by using an osmorespirometry assay. The results have shown that oxygen consumption rate of the fed fish was approximately 3 times higher than that of the unfed fish in early evening to support specific dynamic action. Digestion and ingestion processes were likely to be completed within 18–20 h in parallel with the ammonia excretion noticeable in early morning. Under resting metabolism, metabolic oxygen consumption was influenced by diel phase, but no effect was noted in ammonia excretion. As a nocturnal species, O. marmorata exhibited standard aerobic metabolic mode under dark phase followed by light phase, with high oxygen consumption rate found in either fed or unfed fish. It can be confirmed that both the diel phase and feeding have a significant interactive impact on oxygen consumption rate, whereas ammonia metabolism is impacted by feeding state. High metabolic rate of O. marmorata supports the nocturnal foraging activity in this fish. This finding suggested that feeding of O. marmorata should be performed during nighttime and water renewal should be conducted during daytime

Synthesis and electrical studies of quaternary chalcogenide semiconductor Cu2ZnSnSe4

Quaternary chalcogenide semiconductor has attracted much attention as absorber-layer materials in solar cells. The absorber-layer material, Cu2ZnSnSe4 (CZTSe) which is a p-type semiconductor that has high absorption coefficient, had been synthesized by using solvothermal method. The variation of concentrations of the Copper (II) Chloride dihydrate have brought some effects towards producing the stoichiometry and non-stoichiometry copper zinc tin selenide that may lead to the improvement of efficiency of solar cells. The synthesized reaction was conducted at 250°C for 24 hours. Properties of the samples have been characterized by X-ray diffraction (XRD) to determine the crystal structure of the sample and X-ray Fluorescence (XRF) to determine the elemental composition of the sample. The electrical properties such as resistance and conductivity have been studied through Van der Pauw configuration. The CZTSe has been successfully synthesized at concentrations of 0.15 M with no impurities phases existed

Paraneoplastic secretion of multiple phosphatonins from a deep fibrous histiocytoma causing oncogenic osteomalacia

Context: Literature suggests that oncogenic osteomalacia is usually caused by a benign mesenchymal tumor secreting fibroblast growth factor subtype-23 (FGF-23), but the involvement of other phosphatonins has only been scarcely reported. We have previously published a seemingly typical case of oncogenic osteomalacia. Following curative neoplasm resection, we now report unique molecular characteristics and biology of this tumor. Case Description: A 25-year-old man had been diagnosed with severe oncogenic osteomalacia that gradually crippled him over 6 years. 68Ga-DOTA-TATE positron emission tomography/computed tomography scan localized the culprit tumor to his left sole, which on resection revealed a deep fibrous histiocytoma displaying a proliferation of spindle cells with storiform pattern associated with multinucleated giant cells resembling osteoclasts. Circulating FGF-23, which was elevated more than 2-fold, declined to undetectable levels 24 h after surgery. Microarray analysis revealed increased tumor gene expression of the phosphatonins FGF-23, matrix extracellular phosphoglycoprotein (MEPE) and secreted frizzled-related protein subtype 4, with elevated levels of all 3 proteins confirmed through immunoblot analysis. Differential expression of genes involved in bone formation and bone mineralization were further identified. The patient made an astonishing recovery from being wheelchair bound to fully self-ambulant 2 months postoperatively. Conclusion: This report describes oncogenic osteomalacia due to a deep fibrous histiocytoma, which coincidentally has been found to induce profound muscle weakness via the overexpression of 3 phosphatonins, which resolved fully upon radical resection of the tumor. Additionally, genes involved in bone formation and bone remodeling contribute to the molecular signature of oncogenic osteomalacia

Evaluation of crystalline amino acids as potent stimulatory chemoattractants for the slipper lobster Thenus orientalis

Intensive research on the effectiveness of chemoattractants has been widely explored to improve the feed qualities in expanding crustacean farming. Taste preferences in slipper lobster remained unknown despite their significant contribution to the lobster fisheries. Chemoattractants allow better performance in aquaculture species by increasing food attractiveness and palatability. Amino acids (AA) have been leading in previous research on crustacean feeding behavior. Given that slipper lobster possesses chemoreceptors to detect and orient towards food, this study investigated an approach to identify the AA with the most potent chemoattractant in eliciting a response from slipper lobster. Behavioral assays were performed to evaluate the responses of slipper lobster Thenus orientalis (carapace length, 52.34 ± 1.52 mm) on 15 crystalline AA and three derivatives of AA (DAA) at three concentrations between 10̄⁻¹ and 10⁻³ M as test substances (TS). Meretrix sp. extract was used as a positive control and clean filtered seawater as a negative control. The behavioral responses of 14 T. orientalis were evaluated based on their antennular flicking rate, third maxillipeds activity, and substrate probing by the pereiopods. T. orientalis responded to the solutions of single AA down to a concentration of 10⁻³ M, excluding histidine and serine. The behavioral activity displayed by T. orientalis increased with the TS concentrations. L-glutamic acid monosodium salt monohydrate, betaine, and glycine solutions elicited the most behavioral responses, whereas histidine exhibited the lowest behavioral responses. Conclusively, L-glutamic acid monosodium salt monohydrate, betaine, and glycine can be potential chemoattractants for T. orientalis