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Fulltext Length-weight relationship of six fish species from Sepang Besar River Estuary, Malaysia

Ya, N. A., Singh, H. R., Samat, A., Mohd Rashid, H. N., Ramli, N. H., Makhtar, N., et al.

Journal of Advanced Research in Applied Sciences and Engineering Technology, 2015;1(1):27-35.
MyJurnal

Length-weight relationship (LWR) of six fish species from the Sepang Besar River estuary,
Peninsular Malaysia were analyzes. A total of 594 individuals belonging to six species namely Arius
sagor, Photopectoralis bindus, Plotosus lineatus, Toxotes chatareus, Toxotes jaculatrix, and Thryssa
dussumieri collected from April 2014 to February 2015 were measured and weighed. Among them, four
species showed positive allometric growth and the other two species showed negative allometric
growth. The exponent b value of LWR ranged between 2.94 (Toxotes chatareus) and 3.50
(Photopectoralis bindus). This outcome of the present study has contributed to the knowledge of basic
information on the length–weight relationship of six most abundant species in Sepang Besar River
estuary which is important for future ecological studies and assist in fishery management. Copyright
© 2015 Penerbit Akademia Baru - All rights reserved.
Fulltext Molecular phylogeny of the bamboo sharks (Chiloscyllium spp.)

Masstor NH, Samat A, Nor SM, Md-Zain BM

Biomed Res Int, 2014;2014:213896.
PMID: 25013766 DOI: 10.1155/2014/213896

Chiloscyllium, commonly called bamboo shark, can be found inhabiting the waters of the Indo-West Pacific around East Asian countries such as Malaysia, Myanmar, Thailand, Singapore, and Indonesia. The International Union for Conservation of Nature (IUCN) Red List has categorized them as nearly threatened sharks out of their declining population status due to overexploitation. A molecular study was carried out to portray the systematic relationships within Chiloscyllium species using 12S rRNA and cytochrome b gene sequences. Maximum parsimony and Bayesian were used to reconstruct their phylogeny trees. A total of 381 bp sequences' lengths were successfully aligned in the 12S rRNA region, with 41 bp sites being parsimony-informative. In the cytochrome b region, a total of 1120 bp sites were aligned, with 352 parsimony-informative characters. All analyses yield phylogeny trees on which C. indicum has close relationships with C. plagiosum. C. punctatum is sister taxon to both C. indicum and C. plagiosum while C. griseum and C. hasseltii formed their own clade as sister taxa. These Chiloscyllium classifications can be supported by some morphological characters (lateral dermal ridges on the body, coloring patterns, and appearance of hypobranchials and basibranchial plate) that can clearly be used to differentiate each species.
Fulltext Population growth, trophic level, and reproductive biology of two congeneric archer fishes (Toxotes chatareus, Hamilton 1822 and Toxotes jaculatrix, Pallas 1767) inhabiting Malaysian coastal waters

Simon KD, Bakar Y, Samat A, Zaidi CC, Aziz A, Mazlan AG

J Zhejiang Univ Sci B, 2009 Dec;10(12):902-11.
PMID: 19946954 DOI: 10.1631/jzus.B0920173

Population growth, trophic level, and some aspects of reproductive biology of two congeneric archer fish species, Toxotes chatareus and Toxotes jaculatrix, collected from Johor coastal waters, Malaysia, were studied. Growth pattern by length-weight relationship (W=aL(b)) for the sexes differed, and exhibited positive allometric growth (male, female and combined sexes of T. chatareus; female and combined sexes of T. jaculatrix) and isometric growth (male samples of T. jaculatrix only). Trophic levels of both species were analyzed based on 128 specimens. The results show that, in both species, crustaceans and insects were the most abundant prey items, and among crustaceans the red clawed crab Sesarma bidens and Formicidae family insects were the most represented taxa. The estimated mean trophic levels for T. chatareus and T. jaculatrix were 3.422+/-0.009 and 3.420+/-0.020, respectively, indicating that they are largely carnivores. Fecundity of T. chatareus ranged from 38 354 to 147 185 eggs for females with total length ranging from 14.5 to 22.5 cm and total body weight from 48.7 to 270.2 g, and T. jaculatrix 25 251 to 150 456 eggs for females with total length ranging from 12.2 to 23.0 cm and total body weight from 25.7 to 275.0 g. Differences in values of gonadosomatic and hepatosomatic indexes calculated for both species in this study may have resulted from uneven sample size ranges.
Fulltext Mechanical Properties and In Vitro Evaluation of Thermoplastic Polyurethane and Polylactic Acid Blend for Fabrication of 3D Filaments for Tracheal Tissue Engineering

Abdul Samat A, Abdul Hamid ZA, Jaafar M, Yahaya BH

Polymers (Basel), 2021 Sep 13;13(18).
PMID: 34577988 DOI: 10.3390/polym13183087

Surgical reconstruction of extensive tracheal lesions is challenging. It requires a mechanically stable, biocompatible, and nontoxic material that gradually degrades. One of the possible solutions for overcoming the limitations of tracheal transplantation is a three-dimensional (3D) printed tracheal scaffold made of polymers. Polymer blending is one of the methods used to produce material for a trachea scaffold with tailored characteristics. The purpose of this study is to evaluate the mechanical and in vitro properties of a thermoplastic polyurethane (TPU) and polylactic acid (PLA) blend as a potential material for 3D printed tracheal scaffolds. Both materials were melt-blended using a single screw extruder. The morphologies (as well as the mechanical and thermal characteristics) were determined via scanning electron microscopy (SEM), Fourier Transform Infrared (FTIR) spectroscopy, tensile test, and Differential Scanning calorimetry (DSC). The samples were also evaluated for their water absorption, in vitro biodegradability, and biocompatibility. It is demonstrated that, despite being not miscible, TPU and PLA are biocompatible, and their promising properties are suitable for future applications in tracheal tissue engineering.
Myocardial Disarray and Fibrosis across Hypertrophic Cardiomyopathy Stages Associate with ECG Markers of Arrhythmic Risk

Ashkir Z, Samat AHA, Ariga R, Finnigan L, Jermy S, Akhtar MA, et al.

Eur Heart J Cardiovasc Imaging, 2024 Oct 17.
PMID: 39417278 DOI: 10.1093/ehjci/jeae260

BACKGROUND: Myocardial disarray, an early feature of hypertrophic cardiomyopathy (HCM) and a substrate for ventricular arrhythmia, is poorly characterised in prehypertrophic sarcomeric variant carriers (SARC+LVH-).
OBJECTIVES: Using diffusion tensor cardiac magnetic resonance (DT-CMR) we assessed myocardial disarray and fibrosis in both SARC+LVH- and HCM patients and evaluated the relationship between microstructural alterations and electrocardiographic (ECG) parameters associated with arrhythmic risk.
METHODS: Sixty-two individuals (24 SARC+LVH-, 24 HCM and 14 matched controls) were evaluated with multiparametric CMR including stimulated echo acquisition mode (STEAM) DT-CMR, and blinded quantitative 12-lead ECG analysis.
RESULTS: Mean diastolic fractional anisotropy (FA) was reduced in HCM compared to SARC+LVH- and controls (0.49±0.05 vs 0.52±0.04 vs 0.53±0.04, p=0.009), even after adjustment for differences in extracellular volume (ECV) (p=0.038). Both HCM and SARC+LVH- had segments with significantly reduced FA relative to controls (54% vs 25% vs 0%, p=0.002). Multiple repolarization parameters were prolonged in HCM and SARC+LVH-, with corrected JT interval (JTc) being most significant (354±42ms vs 356±26ms vs 314±26ms, p=0.002). Among SARC+LVH-, JTc duration correlated negatively with mean FA (r=-0.6, p=0.002). In HCM, the JTc interval showed a stronger association with ECV (r=0.6 p=0.019) than FA (r=-0.1 p=0.72). JTc discriminated SARC+LVH- from controls (Area-under-the-receiver-operator-curve 0.88, CI 0.76-1.00, p<0.001), and in HCM correlated with the ESC HCM sudden cardiac death risk score (r=0.5, p=0.014).
CONCLUSION: Low diastolic FA, suggestive of myocardial disarray, is present in both SARC+LVH- and HCM. Low FA and raised ECV were associated with repolarization prolongation. Myocardial disarray assessment using DT-CMR and repolarization parameters such as the JTc interval demonstrate significant potential as markers of disease activity in HCM.