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The establishment and survival of the population of species in their breeding ground can be attributed to the species’ reproductive characteristic and capacity. The Monopterus albus species is an introduced fish in the Philippines. It is a protogynous hermaphrodite which has a natural ability for sex reversal. This study describes the histomorphology of the different stages of gonadal maturation and determines the concentration levels of the steroid hormones 17ß-estradiol (E2) and testosterone (T) in the blood plasma. These aim to a further understanding on the gonadal development and sex differentiation of the rice paddy eel as a hermaphroditic fish. Fish samples were collected randomly from farm ponds located in three provinces within the island of Luzon, Philippines. The sexual identity of the fish was categorized based on the presence or absence of ovarian and testicular tissues. Histological analysis of the gonad showed that immature, maturing-matured female gonad exhibited ovarian tissues of varying stages. The intersex gonad showed the existence of both ovarian and testicular tissues. Enzyme-linked immunosorbent assay (ELISA) was used to determine the concentration levels of gonadal steroid hormones. Differences in the concentration levels of the two hormones were evident across all the stages of gonad maturation. The functional role of these hormones in vitellogenesis and spermatogenesis leads to the development of this sex-changing gonads. This reproductive characteristic contributes to our understanding of the reproductive success of hermaphroditic fish.

Arius manillensis is an endemic and economically important catfish of Laguna de Bay, Philippines. This study generated data on some aspects of its reproductive biology that are vital for the enhancement of propagation efforts for inland fisheries in the Southeast Asian region. Monthly assessments were conducted for one whole year to establish the distinct spawning season(s) through determinations of gonadosomatic index (GSI), fecundity through counting the number of two classes of follicles, and size at sexual maturity. Sex ratio was taken into account. Peaks in GSI occurred in March to April and July to August. These peaks correspond with months of peaks in fecundity. The parallel patterns of these reproductive aspects strengthen the occurrence of two distinct spawning seasons. GSI did not show significant correlation with body parameters while fecundity was significantly correlated with body weight (BW) and length (BL) and gonad weight (GW). Size and weight of apparent sexual maturity or peak reproductive capacity is about 20 cm and 200 g, respectively. Sex ratio was female-biased (2.11: 1). Female dominance indicates a unique reproductive behavior of A. manilensis where males could have evolved survival mechanism(s) to elude capture during breeding seasons and evidently during spawning on the cold months.

Objective: To investigate if the protective effect of α-tocopherol against the impact of ethanol on brain morphogenesis involved the activity of the selenoproteins phospholipid hydroperoxide glutathione peroxidase (PHGPx; GPx4) and selenoprotein P (SelPP) that have roles against oxidative stress.Methods: Forty female mice were randomly assigned into natural control (CON), positive control (ETOH), low-, medium-, and high-α-tocopherol-supplemented-ethanol groups (LTOC, MTOC, HTOC, respectively). CON received drinking water without ethanol while ETOH, LTOC, MTOC and HTOC groups received 20% ethanol in drinking water. The supplemented groups were given respective dosages of α-tocopherol, 0.410, 0.819, and 1.640 mg/g body weight, at day 14 before mating onwards to the day 9 of gestation. At 10.5 ED of gestation (1 100 h), the pregnant females were sacrificed by cervical dislocation and the embryos were harvested. Total RNA were extracted, cDNA synthesis and qRT-PCR analyses were carried out.Results: The level of expression of PHGPx in the positive control was significantly lower than that of the natural control. Among the three α-tocopherol-supplemented groups, only the medium dose-group was significantly higher than the positive control. The level of expression of SelPP in the positive control was significantly lower than those of the natural control, the low- and medium-dose-tocopherol supplemented groups. In the high dose-α-tocopherol supplemented group, the level of expression was not significantly different from the positive control but significantly lower than the natural control.Conclusions: The activity of the selenoproteins PHGPx and SelPP are involved in the internetwork of antioxidative enzymes with vitamin E when given up to a medium dose only and is one of the possible pathways of shielding embryonic development against the impact of ethanol on brain morphogenesis. This study strengthens the impact of dietary α-tocopherol and Selenium supplement during the critical period of pregnancy.

The most preferred decellularization technique in creating bioscaffolds for complex organs such as kidneys is through detergent perfusion. Detergents such as sodium dodecyl sulfate (SDS) flow to the kidneys to remove cells but using this technique alone requires long treatment times. Coupling this technique with sonication treatment decreases decellularization time but may cause damages in the microarchitecture of the kidney. This study evaluated the effects of decellularization parameters specifically SDS concentration (0.25%, 0.625%, and 1.0%wt/vol), flowrate (15, 30, and 45 mL/min), and sonicator power (0, 60, and 120 W) on the length of time needed to produce acellular and intact bioscaffolds. Decellularization was carried out by perfusing SDS to the renal artery of the cadaveric porcine kidney while exposed to sonication treatment. Results showed that a significant decrease in decellularization time was observed in producing acellular scaffold when perfusion decellularization was coupled with sonication. In addition, SDS concentration, SDS flowrate, and sonicator power had significant effects on the decellularization time while only sonicator power had a significant effect on the microarchitecture integrity of the scaffold. Lastly, H&E results showed that the produced bioscaffold showed complete cell removal with only minimal to moderate disruptions on the microarchitecture of the kidney.

Objective To assess the histoarchitecture of the maternal liver and kidney as influenced by selenium supplementation within the periconception period and to determine which of the periconception stages of selenium intake is most favorable of the liver and kidney. Methods Thirty-six 7-week-old female mice were divided into four groups where all groups were given 6.0 g of food pellets per day. Un-supplemented group (U) received no selenium in the food pellet, Pre-gestation supplemented group (P) was given 3.0 μg selenium/d for 21 d, Pre-gestation to Gestation supplemented group (PG) was given 3.0 μg selenium/d for 37 d, and Gestation supplemented group (G) was given 3.0 μg selenium/d for 16 d only. Results The occurrences of vacuolated hepatocytes and congested central veins in the liver were observed. The P and the G groups incurred the lowest and highest percent occurrence, respectively, of murine mothers that exhibited presence of vacuolated hepatocytes. The mean percent occurrence of congested central veins did not significantly vary among groups. The occurrences of shrunken and swollen glomeruli were observed in the kidney. The mean percent occurrence of shrunken glomeruli showed that P and G groups were significantly lower than those of U and PG groups. The mean percent occurrences of swollen glomeruli did not vary significantly among groups. Conclusion The histological analyses of the liver and the kidney obtained from different stages of periconception indicate that selenium supplementation would be best during pregestation stage.

Objective To determine the influence of maternal Isoflavone-supplementation during peri-conception period on the reproductive organs of the first generation (F1) murine weanling-stage offspring. Methods Sexually-mature female mice were randomly distributed into the Control group (C) that was fed with food pellets only, treatment groups that were designated as High Dose (HD), Medium Dose (MD) and Low dose (LD) that were fed with food pellets + Isoflavone Genistein dosages of 150.0, 100.0, and 50.0 mg/kg body weight, respectively. Supplement was given two weeks prior to mating and throughout a 21-day gestation period. The pups that were delivered on the 21st day were allowed to mature up to the 28th-day postnatal age then sacrificed by cervical dislocation. The testis and epididymis of males and ovaries and oviducts of females were obtained for histological analyses. Results Histological analysis of the testes showed clogged luminal spaces and indistinct population of spermatogenic cells in the HD group while the development of the ovaries from all test groups appeared intact. The luminal and tubular diameter of epididymis were unaffected in the isoflavone-supplemented groups. The epididymis of HD group exhibited poorly developed cauda segment and atrophy of the caput segment but not for MD and LD groups. The oviducts of the HD and MD groups exhibited collapsed muscularis layer and indistinguishable mucosa layer with HD being the more severe. The LD and Control groups showed well-developed mucosa layer. Conclusion Results showed that maternal isoflavone-supplementation when administered at a high dose of 150 mg/kg body weight during peri-conception period can induce adverse effects on the reproductive organs of first generation (F1) murine weanling-stage offspring.

Objective To investigate the effects of pregestational and gestational exposure to an isoflavone of sexually mature female mice on their reproductive health and on the postnatal development of their offspring. Methods Sexually-mature ICR female mice were randomly segregated into Control group 1 that was given the normal diet consisting of food pellets, Control group 2 that was given food pellets with additional corn oil of 2 mL/kg bodyweight. The three (3) isoflavone treatment groups were given 50 mg/kg body weight, 100 mg/kg body weight and 150 mg/kg body weight for low dose (LD), medium dose (MD) and high dose (HD) respectively. Treatments were administered 2 weeks prior to mating and gestation and thereafter until parturition. The delivered pups were weaned up until 21 days. On the 21st day, postnatal development were determined, excluding the birth weight of pups which was measured one day post-parturition. The dams were sacrificed as well and the markers of maternal health were determined. Results There were no significant differences found between the control groups and the treatment groups in terms of the markers of maternal reproductive health. For postnatal development, only HD group displayed a significantly higher mean AGD from the other groups. Conclusions The data implies that exposure to the isoflavone genestein, with the given dosages, does not impact the maternal reproductive health while the high dose brings about masculinization of the pups which implies that isoflavone exerts its action as an endocrine disruptor affecting postnatal development. This could be attributed to the decrease in estrogen due to the inhibition of aromatase, an enzyme involved in estrogen synthesis.

Objective To assess the parasitic infestation of vegetables in selected markets in Metro Manila, Philippines. Methods A total of 80 vegetables were purchased from public and private markets in Munoz, Quezon City, and Alabang, Muntinlupa City. Vegetables were washed, and the washings were collected and examined for parasitic organisms. Results In all vegetables examined, 36 of 80 (45.0%) were infested with parasitic organisms. Vegetables obtained from Muntinlupa City showed that 17 of 40 (42.5%) have parasitic infestation as compared with those obtained from Quezon City with 19 of 40 (47.5%). Significant differences on the parasitic organisms existed between the public and private markets and between the two locations (P Conclusions Findings indicate that vegetables can be potential source of parasitic infection. There is a need to be vigilant in ensuring that foodstuffs sold in our market systems are safe and fit for consumption.

Heavy metal levels (Pb and Cu) on adult mud crabs (Scylla spp.) from the East Bataan Coast were determined. Muscle tissue from each crab was processed through nitric acid digestion and analyzed using atomic absorption spectroscopy. The average concentrations in the samples were 3.37 × 10(-3) and 1.01 mg/L-both within WHO acceptable limits. These were contrasted with the levels found in sediments from catch and grow-out sites (17.9, 14.5, 37.8, and 31.3 mg/L) and were found to be significantly lower in concentration. It takes 3-8 months before adult mud crabs can be harvested from grow-out ponds, and the data suggests that the organisms, even when constantly exposed to high levels of Pb and Cu, do not bio-accumulate toxic levels of these heavy metals. Mud crabs constitute a major economic natural resource in the Philippines and in the province of Bataan. Commanding high prices due to the quality of its meat, it is also a preferred culture product due to its impressive size, rapid growth rate, and high flesh content. Mud crab culture in Bataan is primarily driven by grow-out of captured juveniles in pen or pond cultures sourced from nearby bodies of water-making them vulnerable to prolonged exposure to pollutants. The East Bataan Coast shares its waters with the polluted Manila Bay, giving rise to the concern of the quality of seafood acquired from the area.

Cdc6 is a key regulator of DNA replication in eukaryotes. In this work, the expression pattern of an Arabidopsis cdc6 homologue is characterized by RT-PCR and in situ hybridization. The data suggest that cdc6At expression is cell cycle regulated. During development, high cdc6At mRNA levels are found in regular cycling cells. In addition, cdc6At expression is also observed in cells that are probably undergoing endoreduplication, suggesting a possible role of Cdc6At in this process in plants.

Eukaryotic DNA replication requires an ordered and regulated machinery to control G1/S transition. The formation of the pre-replicative complex (pre-RC) is a key step involved in licensing DNA for replication. Here, we identify all putative components of the full pre-RC in the genome of the model plant Arabidopsis thaliana. Different from the other eukaryotes, Arabidopsis houses in its genome two putative homologs of ORC1, CDC6 and CDT1. Two mRNA variants of AtORC4 subunit, with different temporal expression patterns, were also identified. Two-hybrid binary interaction assays suggest a primary architectural organization of the Arabidopsis ORC, in which AtORC3 plays a central role in maintaining the complex associations. Expression profiles differ among pre-RC components suggesting the existence of various forms of the complex, possibly playing different roles during development. In addition, the expression of the putative pre-RC genes in non-proliferating plant tissues suggests that they might have roles in processes other than DNA replication licensing.

This study aims to assess the bioaccumulation of total lead and the effect of heavy metal on the muscles of fish obtained in the coastal lagoon of the Manila Bay. Fish species muscles were assessed for lead concentrations and were examined for histological alterations. Results showed that lead bioaccumulation in the muscles, and a degree of disintegration in the muscle fibers of all the fish examined were found.