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1.
Nat Prod Res ; : 1-8, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38949646

ABSTRACT

Recent research has indicated that Panax notoginseng saponins (PNS) extracted from the radix of Panax notoginseng (Burkill) F. H. Chen exert antidepressant effects. This study aimed to assess the antidepressive effects of ginsenoside Rg1 and PNS in a depression model induced by chronic unpredictable mild stress (CUMS). Over a period of three weeks, rats were administered ginsenoside Rg1 at a dose of 30 mg/kg and PNS at dosages ranging from 100 to 200 mg/kg body weight per day. To assess how ginsenoside Rg1 and PNS influence depression-like behaviours in rats, various assessments were conducted, including coat state evaluation, forced swim test, and elevated plus maze test. The levels of cortisol and testosterone in serum samples were analysed using the liquid chromatography-electrospray ionisation tandem mass spectrometry (LC-ESI-MS/MS) method. LC-ESI-MS/MS method provides precise and accurate results. The lower limit of quantification values for cortisol and testosterone were determined as 100 and 2 pg/mL, respectively. Our data demonstrated that both ginsenoside Rg1 and PNS significantly reversed depression-like behaviour in rats by improving coat condition, reducing immobility time in the forced swim test, and increasing time spent in the open arms of the elevated plus maze test. Furthermore, ginsenoside Rg1 and PNS exhibited a regulatory effect on cortisol and testosterone levels in plasma. These findings suggest that ginsenoside Rg1 and PNS may be potential antidepressants in clinical treatment.

2.
Reprod Biol ; 23(4): 100798, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37717489

ABSTRACT

In the present study, we attempted to improve the developmental competence of vitrified immature porcine oocytes by the preservation of mitochondrial properties using Cyclosporin A (CsA, inhibitor of mitochondrial membrane permeability transition) and Docetaxel (stabilizer of microtubules, hence mitochondrial distribution). In Experiment 1, Mitotracker red staining revealed reduced mitochondrial activity (MA) in vitrified/warmed oocytes at 0 and 22 h of in vitro maturation (IVM) compared with fresh ones. However, by at 46 h of IVM, MA levels in vitrified oocytes were similar to those in fresh control. Treatment of oocytes with CsA or Docetaxel improved MA at 0 h and 22 h of IVM compared with non-treated vitrified oocytes. However, there were no significant differences among groups in percentages of survival, maturation and embryo development after subsequent IVM and parthenogenetic activation. Nevertheless, a pretreatment with a combination of 10 µg/mL CsA and 0.05 µM Docetaxel improved the blastocyst formation of vitrified oocytes compared with non-treatment counterparts (11.2 ± 1.6% vs 5.9 ± 1.6%, P < 0.05). In conclusion, vitrification reduced mitochondrial activity in GV-stage oocytes during 0-22 h of IVM; however, it was normalized by 46 h IVM. Docetaxel or CsA pretreatment alone did not improve development competence of vitrified oocytes. However, pretreatment with a combination of CsA and Docetaxel could improve blastocyst formation rates.


Subject(s)
Cyclosporine , Vitrification , Swine , Animals , Cyclosporine/pharmacology , Docetaxel/pharmacology , Cryopreservation/veterinary , Oocytes , Embryonic Development
3.
Adv Mater ; 35(40): e2304735, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37363886

ABSTRACT

The prognosis in cases of pancreatic ductal adenocarcinoma (PDAC) with current treatment modalities is poor owing to the highly desmoplastic tumor microenvironment (TME). Herein, a ß-glucans-functionalized zinc-doxorubicin nanoparticle system (ßGlus-ZnD NPs) that can be orally administered, is developed for targeted PDAC therapy. Following oral administration in PDAC-bearing mice, ßGlus-ZnD NPs actively target/transpass microfold cells, overcome the intestinal epithelial barrier, and then undergo subsequent phagocytosis by endogenous macrophages (ßGlus-ZnD@Mϕ). As hitchhiking cellular vehicles, ßGlus-ZnD@Mϕ transits through the intestinal lymphatic system and enters systemic circulation, ultimately accumulating in the tumor tissue as a result of the tumor-homing and "stealth" properties that are conferred by endogenous Mϕ. Meanwhile, the Mϕ that hitchhikes ßGlus-ZnD NPs is activated to produce matrix metalloproteinases, destroying the desmoplastic stromal barrier, and differentiates toward the M1 -like phenotype, modulating the TME and recruiting effector T cells, ultimately inducing apoptosis of the tumor cells. The combination of ßGlus-ZnD@Mϕ and immune checkpoint blockade effectively inhibits the growth of the primary tumor and suppresses the development of metastasis. It thus represents an appealing approach to targeted PDAC therapy.


Subject(s)
Carcinoma, Pancreatic Ductal , Pancreatic Neoplasms , beta-Glucans , Animals , Mice , Pancreatic Neoplasms/drug therapy , Pancreatic Neoplasms/genetics , Macrophages/pathology , Carcinoma, Pancreatic Ductal/drug therapy , Carcinoma, Pancreatic Ductal/genetics , Carcinoma, Pancreatic Ductal/pathology , Tumor Microenvironment , Pancreatic Neoplasms
4.
Res Microbiol ; 174(7): 104094, 2023.
Article in English | MEDLINE | ID: mdl-37356782

ABSTRACT

Bacterial plant pathogens must cope with various environmental conditions and defenses from their hosts for colonization and infection. Heat shock proteins (HSPs) play critical roles in a variety of cellular processes, such as the maintenance of cellular homeostasis in response to environmental stress. However, the significance of HSP40 family protein DnaJ in virulence of plant pathogenic bacteria has not yet been explored. To elucidate the function of DnaJ in Pseudomonas cichorii JBC1 (PcJBC1) virulence, we generated dnaJ-deficient (JBC1ΔdnaJ) mutant using CRISPR-CAS9. The disease severity by JBC1ΔdnaJ was significantly reduced compared with wild-type (WT) and dnaJ-complemented (JBC1ΔdnaJ + pdnaJ) strain. The defect of DnaJ suppressed siderophore production, extracellular DNA (eDNA) release, biofilm formation, and swarming motility and made the strain sensitive to stresses such as heat and H2O2. The supplementation of eDNA recovered the amount of biofilm formation by JBC1ΔdnaJ. Our results indicate that DnaJ is a key player in the survival and colonization of bacterial plant pathogens on plant surfaces as well as bacterial responses to abiotic and biotic stresses, which are determinative to cause disease. These findings can broaden our understanding of plant and bacterial pathogen interactions.


Subject(s)
Escherichia coli Proteins , HSP40 Heat-Shock Proteins , HSP40 Heat-Shock Proteins/genetics , HSP40 Heat-Shock Proteins/metabolism , Virulence , Hydrogen Peroxide , Heat-Shock Proteins/genetics , Plants/metabolism , Bacterial Proteins/metabolism
5.
Int Med Case Rep J ; 15: 431-435, 2022.
Article in English | MEDLINE | ID: mdl-36033341

ABSTRACT

We report three clinical cases using a submental flap to reconstruct the half-tongue defects after tongue cancer surgery at Hue Central Hospital (Hue city, Vietnam). The size of the flap ranged 30-60mm. The time to take flap ranged 50-60 minutes. All three patients did not have liquid accumulation, wound infection and bleeding after surgery; the flap survived well. All patients were taken the nasogastric tube out after ten days and discharged after two weeks. Postoperative functional (speech, swallowing) and tongue aesthetic assessments (symmetry) were good. These cases highlight that the submental flap is a choice for patients with flaws in the tongue. It ensures both functional and aesthetic for the regenerative tongue and donor site.

6.
ACS Nano ; 16(8): 12403-12414, 2022 08 23.
Article in English | MEDLINE | ID: mdl-35920682

ABSTRACT

The in situ transformation of low-toxicity precursors into a chemotherapeutic agent at a tumor site to enhance the efficacy of its treatment has long been an elusive goal. In this work, a zinc-based zeolitic imidazolate framework that incorporates pharmaceutically acceptable precursors is prepared as a nanoreactor (NR) system for the localized synthesis of an antitumor drug. The as-prepared NRs are administered intratumorally in a tumor-bearing mouse model and then irradiated with ultrasound (US) to activate the chemical synthesis. The US promotes the penetration of the administered NRs into the tumor tissue to cover the lesion entirely, although some NRs leak into the surrounding normal tissue. Nevertheless, only the tumor tissue, where the H2O2 concentration is high, is adequately exposed to the as-synthesized antitumor drug, which markedly impedes development of the tumor. No significant chemical synthesis is detected in the surrounding normal tissue, where the local H2O2 concentration is negligible and the US irradiation is not directly applied. The as-proposed tumor-specific in situ synthesis of therapeutic molecules induces hardly any significant in vivo toxicity and, thus, is potentially a potent biocompatible approach to precision chemotherapy.


Subject(s)
Antineoplastic Agents , Neoplasms , Zeolites , Mice , Animals , Drug Carriers/chemistry , Hydrogen Peroxide/chemistry , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Antineoplastic Agents/chemistry , Neoplasms/diagnostic imaging , Neoplasms/drug therapy , Neoplasms/pathology , Zeolites/chemistry , Nanotechnology
7.
Theriogenology ; 166: 21-28, 2021 May.
Article in English | MEDLINE | ID: mdl-33667861

ABSTRACT

Our aim was to establish an efficient culture system to produce embryos by SCNT of the endangered Vietnamese I pig. Reducing the serum concentration from 10.0% to 0.2% during culture efficiently synchronized I pig fibroblasts used as donor cells at the G0/G1 stage. Oocyte maturation in a defined porcine oocyte medium (POM) supplemented with EGF and gonadotrophins resulted in higher cleavage and blastocyst rates compared with a non-defined POM containing pig follicular fluid (but without EGF) and both the defined and non-defined variants of NCSU-37. For embryo culture PZM3 and PZM5 media were superior to NCSU-37, in terms of the percentage of cleaved embryos. Addition of serum to PZM3 medium on Day 5 of culture (Day 0 = SCNT) improved blastocyst development. When SCNT embryos were transferred at the blastocyst stage, 7 of 11 recipients became pregnant. However, live offspring were not obtained. In conclusion, we established a system for the production of I pig embryos by SCNT and achieved blastocyst production rate at 26.4% by improving culture systems for donor cells, oocytes and embryos culture. Transfer of embryos resulted in pregnancies; however, live offspring were not obtained.


Subject(s)
Blastocyst , Nuclear Transfer Techniques , Animals , Asian People , Cell Cycle , Cloning, Organism/veterinary , Culture Media , Embryo Culture Techniques/veterinary , Embryonic Development , Female , Humans , Nuclear Transfer Techniques/veterinary , Oocytes , Pregnancy , Swine
8.
Sci Total Environ ; 764: 144231, 2021 Apr 10.
Article in English | MEDLINE | ID: mdl-33385649

ABSTRACT

The removal of organics and ammonium from domestic wastewater was successfully achieved by a flat-panel air-cathode microbial fuel cell (FA-MFC). To elucidate the reason for complete ammonium removal in the single-chamber MFCs, microbial communities were analyzed in biofilms on the surface of each anode, separator, and cathode of separator-electrode assemblies (SEAs). The spatial distribution of bacterial families related to the nitrogen cycle varied based on local conditions. Since oxygen diffusing from the air-cathode created a locally aerobic condition, ammonia-oxidizing bacteria (AOB) Nitrosomonadacea and nitrite-oxidizing bacteria (NOB) Nitrospiraceae were present near the cathode. NOB (~12.1%) was more abundant than AOB (~4.4%), suggesting that the nitrate produced by NOB may be reduced back to nitrite by heterotrophic denitrifiers such as Rhodocyclaceae (~21.7%) and Comamonadaceae (~5%) in the anoxic zone close to the NOB layer. Near that zone, the "nitrite loop" also substantially enriched two nitrite-reducing bacterial families: Ignavibacteriaceae (~18.1%), facultative heterotrophs, and Brocadiaceae (~11.2%), anaerobic ammonium oxidizing autotrophs. A larger inner area of biofilm contained abundant heterotrophic denitrifiers and fermentation bacteria. These results indicate that the large-surface SEA of FA-MFC allows counter-diffusion between substrates and oxygen, resulting in interactions of bacteria involved in the nitrogen cycle for complete ammonium removal.


Subject(s)
Ammonium Compounds , Bioelectric Energy Sources , Biofilms , Bioreactors , Humans , Nitrites , Nitrogen , Wastewater
9.
Chemosphere ; 263: 128340, 2021 Jan.
Article in English | MEDLINE | ID: mdl-33297266

ABSTRACT

Anaerobic ammonium oxidation (anammox), a low-energy-consuming technology, can be used to remove nitrogen from industrial saline wastewater. However, high salinity inhibits anammox microbial activity. This study investigated the effect of salinity on nitrogen removal performance and microbial community structure. The experiment used an up-flow anammox reactor fed with synthetic wastewater with salinity increased from 0.5 to 2.5%. Results indicated that 80% nitrogen removal efficiency can be achieved at 2% salinity with a nitrogen loading rate of 2.0 kg-N/m3/d. Anammox performance significantly deteriorated at 2.5% salinity. High-throughput sequencing revealed that Planctomycetes (representative anammox bacteria) increased with salinity, replacing Proteobacteria (representative heterotrophic denitrifying bacteria) in the microbial community. qPCR analysis indicated that relative abundance of "Candidatus Kuenenia" within anammox bacteria increased from 3.96 to 83.41%, corresponding to salinity of 0.5-2.0%, and subsequently decreased to 63.27% at 2.5% salinity, correlating with nitrogen-removal performance. Thus, anammox has potential in nitrogen removal from wastewater with salinity up to 2%.


Subject(s)
Microbiota , Nitrogen , Bioreactors , Denitrification , Oxidation-Reduction , Salinity , Sewage , Wastewater
10.
Sci Total Environ ; 742: 140596, 2020 Nov 10.
Article in English | MEDLINE | ID: mdl-33167297

ABSTRACT

The annual flood pulse of the Mekong River is crucial to sustain agriculture production, nutrition, and the livelihood of millions of people living in the Vietnamese part of the Mekong Delta (VMD). However, climate change impacts on precipitation, temperature and sea-level combined with land subsidence, upstream hydropower development, and water infrastructures (i.e. high-dykes construction) are altering the hydrological regime of the VMD. This study investigates future changes in flood hazard and agricultural production caused by these different scales of human-induced stresses. A quasi- two-dimensional (quasi-2D) hydrodynamic model was used to simulate eight scenarios representing the individual and compound impacts of these drivers for a baseline (1971-2000) and future (2036-2065) period. The scenarios map the most likely future pathway of climate change (RCP 4.5) combined with the best available Mekong upstream hydropower development, and land subsidence scenarios as well as the current delta development plan. We found that sea-level rise and land subsidence would cause the highest changes in flood hazard and damage to rice crop, followed by hydropower and climate change impacts. Expansion of high-dyke areas in two northernmost delta provinces (An Giang and Dong Thap) would have the smallest impact. The combination of all modelled drivers is projected to increase delta inundation extent by 20%, accompanied with prolonging submergence of 1-2 months, and 2-3 times increase in annual flood damage to rice crops in the flood-prone areas of the VMD. These findings of likely increasing risk of tidal induced flood hazard and damage call for well-planned adaptation and mitigation measures, both structural and non-structural.

11.
Anim Sci J ; 91(1): e13412, 2020.
Article in English | MEDLINE | ID: mdl-32618066

ABSTRACT

The Vietnamese Ban pig is a precious genetic resource that needs to be preserved. In vitro embryo production from in vitro matured (IVM) oocytes is an important tool for the utilization of cryopreserved porcine sperm. The aim of this study was to compare two media for the IVM of Ban pig oocytes. Immature oocytes were subjected to IVM either in a non-defined (TCM-199 + pig follicular fluid) or in a defined base medium (POM + epidermal growth factor). At the end of IVM, the oocytes were in vitro fertilized (IVF) with frozen Ban sperm. Ten hours after IVF, the oocytes were either subjected to orcein staining to check fertilization and maturation status or cultured in vitro for 7 days. There was no difference between the two IVM media in terms of percentages of oocyte maturation and blastocyst production. However, the percentage of male pronuclear formation after IVF and the total cell numbers in blastocysts were higher with the defined system. Zygotes obtained by the two IVM systems survived vitrification at similar rates. In conclusion, the two IVM systems were both effective for the production of Ban pig embryos; however, better embryo quality was achieved with the defined one.


Subject(s)
Blastocyst , Embryo, Mammalian , Fertilization in Vitro/methods , In Vitro Oocyte Maturation Techniques/methods , In Vitro Oocyte Maturation Techniques/veterinary , Oocytes , Spermatozoa , Swine , Vitrification , Zygote , Animals , Cryopreservation/veterinary , Female , Male , Vietnam
12.
Biomolecules ; 10(6)2020 06 22.
Article in English | MEDLINE | ID: mdl-32580482

ABSTRACT

Manganese-oxidizing bacteria have been widely investigated for bioremediation of Mn-contaminated water sources and for production of biogenic Mn oxides that have extensive applications in environmental remediation. In this study, a total of 5 Mn-resistant bacteria were isolated from river water and investigated for Mn removal. Among them, Ochrobactrum sp. NDMn-6 exhibited the highest Mn removal efficiency (99.1%). The final precipitates produced by this strain were defined as a mixture of Mn2O3, MnO2, and MnCO3. Optimal Mn-removal performance by strain NDMn-6 was obtained at a temperature range of 25-30 °C and the salinity of 0.1-0.5%. More interestingly, strain NDMn-6 could be resistant to salinities of up to 5%, revealing that this strain could be possibly applied for Mn remediation of high salinity regions or industrial saline wastewaters. This study also revealed the potential of self-detoxification mechanisms, wherein river water contaminated with Mn could be cleaned by indigenous bacteria through an appropriate biostimulation scheme.


Subject(s)
Manganese Compounds/isolation & purification , Ochrobactrum/isolation & purification , Rivers/chemistry , Water Pollutants, Chemical/isolation & purification , Manganese Compounds/chemistry , Manganese Compounds/metabolism , Ochrobactrum/metabolism , Water Pollutants, Chemical/chemistry , Water Pollutants, Chemical/metabolism
13.
J Hazard Mater ; 377: 179-185, 2019 09 05.
Article in English | MEDLINE | ID: mdl-31158587

ABSTRACT

The anaerobic antimonate [Sb(V)] reduction with a solid-state electrode serving as the sole electron donor was demonstrated by employing a bioelectrochemical system. The highest Sb(V) reduction efficiency was observed at the biocathode potential of -0.7 V versus standard hydrogen electrode using a cathode potential range from -0.5 V to -1.1 V. The scanning electron microscopy and energy dispersive X-ray spectroscopy indicated that both amorphous and crystallized Sb2O3 were formed as products of Sb(V) reduction. The irreversible recovery of bioelectrochemical Sb(V), when the cathode potential deviated from the optimal potential, was explained through the alteration in microbial communities, which was further elucidated by the next-generation sequencing of 16S rRNA gene amplicons. Chryseobacterium koreense and Stenotrophomonas nitritireducens were the dominant species of microbial consortia at Sb(V)-reducing biocathodes. This study revealed a novel option for bioremediation of Sb at underground contaminated sites, where the delivery of organic electron donors is limited or ineffective.


Subject(s)
Antimony/chemistry , Bacteria/metabolism , Biodegradation, Environmental , Anaerobiosis , Chryseobacterium/chemistry , Chryseobacterium/metabolism , Electrodes , Electrons , Hydrogen/chemistry , Hydrogen/metabolism , Oxidation-Reduction , RNA, Ribosomal, 16S , Stenotrophomonas/chemistry , Stenotrophomonas/metabolism
14.
Materials (Basel) ; 12(10)2019 May 25.
Article in English | MEDLINE | ID: mdl-31130636

ABSTRACT

Magnesium is an essential element involved in various biochemical processes in the human body. In addition to oral supplementation, topical magnesium application is another conventional form of magnesium delivery for the treatment of skin diseases and muscle inflammation. Cucumber extract is a well-known superfood for human skin. It has been widely used in various skincare product lines because of its known benefits to the skin. The benefit of cucumber extract to the human skin would be significantly enhanced if the cucumber extract was fermented to convert the reducing sugars to beneficial organic acids. In this study, we developed a protocol for lactic acid fermentation of cucumber extract using hydromagnesite as a neutralizing agent. Various lactic acid bacteria were screened for fermentation of cucumber extract. The best fermenting performance was observed with Lactobacillus paracasei, which could convert approximately 13 g/L of reducing sugars (glucose and fructose) to lactic acid and a minor amount of acetic acid within 2 days of incubation. The final fermented cucumber extract contains magnesium in the form of salts of organic acids, which have high absorption ability and bioavailability. The product is a potent ingredient for producing dermal magnesium products.

15.
Anim Sci J ; 90(7): 840-848, 2019 Jul.
Article in English | MEDLINE | ID: mdl-31006939

ABSTRACT

We report the cryopreservation of oocytes from Ban miniature pigs which are endemic in Vietnam. Immature cumulus-oocyte complexes were collected from antral follicles of 7-8 mo old female cyclic Ban pigs and vitrified in micro-drops. Oocyte morphology, lipid content, post-warming survival, nuclear maturation, and embryo development were compared to those of oocytes from commercially slaughtered Landrace × Large white hybrid pigs. The size of oocytes in the two breeds was similar. However, significantly lower amounts of intracellular lipid were detected in Ban oocytes. There was no difference (p > 0.05) between Ban and Landrace × Large white oocytes in percentages of post-warming survival (93.1 ± 3.4% vs. 70.7 ± 16.7%, respectively) and nuclear maturation after in vitro maturation (80.4 ± 5.1% vs. 90.0 ± 1.3% respectively). Similarly, cleavage (30.8 ± 7.8% vs. 10.3 ± 6.1%, respectively) and blastocyst development rates (9.4 ± 5.0% vs. 0.79 ± 0.79, respectively) were not different (p > 0.05) between vitrified Ban and Landrace × Large white oocytes after in vitro fertilization and embryo culture. In conclusion, high survival and maturation rates were achieved after vitrification of immature Ban oocytes and their cryo-tolerance was similar to that of Landrace × Large white oocytes, despite the difference in lipid content. We succeeded to generate reasonable rates of blastocysts from vitrified Ban oocytes by in vitro fertilization.


Subject(s)
Cryopreservation/methods , Oocytes , Swine, Miniature , Tissue Preservation/methods , Animals , Blastocyst , Cell Survival , Cells, Cultured , Embryonic Development , Female , Fertilization in Vitro , In Vitro Oocyte Maturation Techniques , Lipid Metabolism , Oocytes/cytology , Oocytes/metabolism , Oocytes/physiology , Specimen Handling/methods , Swine
16.
J Environ Manage ; 236: 746-754, 2019 Apr 15.
Article in English | MEDLINE | ID: mdl-30772731

ABSTRACT

A total of three bacteria isolated from activated sludge of a wastewater treatment plant were found to reduce selenite to elemental selenium nanoparticles as both amorphous nanospheres and monoclinic nanocrystals. The three isolated strains, which are potential candidates for bioremediation of selenite-contaminated water sources, were designated as Citrobacter sp. NVK-2, Providencia sp. NVK-2A, and Citrobacter sp. NVK-6 based on 16S rRNA sequencing. Despite belonging to the same genus, the kinetics of selenite reduction by strain NVK-2 (Vmax = 58.82 µM h-1, Km = 3737.12 µM) completely differed from that of strain NVK-6 (Vmax = 19.23 µM h-1, Km = 1300.17 µM). The selenite reduction rate by strain NVK-2A (Vmax = 9.26 µM h-1, Km = 3044.73 µM) was the slowest among the investigated microorganisms. The microbial selenite reduction rates according to various organic sources indicated that simple organic sources such as acetate and lactate were better than more complex organic sources such as propionate, butyrate, and glucose for selenite removal. Interestingly, the selenite reduction rate was significantly enhanced when the organic source was strategically divided into small portions and consecutively supplied to the culture.


Subject(s)
Selenium , Sewage , Bacteria , Kinetics , RNA, Ribosomal, 16S , Selenious Acid
17.
J Reprod Dev ; 64(5): 457-462, 2018 Oct 12.
Article in English | MEDLINE | ID: mdl-30101829

ABSTRACT

We compared the efficacy of the microdrop and minimum volume cooling (MVC) methods for the vitrification of in vitro-produced porcine zygotes and blastocysts after equilibration in low concentrations of cryoprotectant agents. Zygotes and blastocysts were equilibrated in 2% (v/v) ethylene glycol and 2% (v/v) propylene glycol for 13-15 min. Then, they were vitrified in a medium comprised of 17.5% ethylene glycol, 17.5% propylene glycol, 0.3 M sucrose, and 50 mg/ml polyvinylpyrrolidone either by either dropping them directly into liquid nitrogen (microdrop method) or placing them on Cryotop sheets in a minimum volume of medium and plunging into liquid nitrogen (MVC method). Both zygotes and blastocysts were successfully vitrified. For the vitrification of zygotes, the MVC and microdrop methods were equally effective; however, for blastocyst vitrification, MVC was superior. For both methods, the vitrification of zygotes produced higher-quality embryos than the vitrification of blastocysts.


Subject(s)
Blastocyst/cytology , Cryopreservation/methods , Cryoprotective Agents/chemistry , Animals , Cold Temperature , Dimethyl Sulfoxide , Embryo Culture Techniques , Ethylene Glycol , Female , Male , Oocytes/physiology , Propylene Glycol , Spermatozoa/physiology , Swine , Vitrification , Zygote
18.
J Environ Manage ; 223: 852-859, 2018 Oct 01.
Article in English | MEDLINE | ID: mdl-29986334

ABSTRACT

Mine wastes from tungsten mine which contain a high concentration of arsenic (As) may expose many environmental problems because As is very toxic. This study aimed to evaluate bioleaching efficiency of As and manganese (Mn) from tungsten mine wastes using the pure and mixed culture of Acidithiobacillus ferrooxidans and A. thiooxidans. The electrochemical effect of the electrode through externally applied voltage on bacterial growth and bioleaching efficiency was also clarified. The obtained results indicated that both the highest As extraction efficiency (96.7%) and the highest Mn extraction efficiency (100%) were obtained in the mixed culture. A. ferrooxidans played a more important role than A. thiooxidans in the extraction of As whereas A. thiooxidans was more significant than A. ferrooxidans in the extraction of Mn. Unexpectedly, the external voltage applied to the bioleaching did not enhance metal extraction rate but inhibited bacterial growth, resulting in a reverse effect on bioleaching efficiency. This could be due to the low electrical tolerance of bioleaching bacteria. However, this study asserted that As and Mn could be successfully removed from tungsten mine waste by the normal bioleaching using the mixed culture of A. ferrooxidans and A. thiooxidans.


Subject(s)
Acidithiobacillus , Arsenic/chemistry , Manganese/chemistry , Arsenic/isolation & purification , Manganese/isolation & purification , Metals , Mining , Tungsten , Waste Management
19.
Bioresour Technol ; 258: 57-63, 2018 Jun.
Article in English | MEDLINE | ID: mdl-29522926

ABSTRACT

A flat-panel air-cathode microbial fuel cell (FA-MFC) is known to overcome the low conductivity and biodegradability of domestic wastewater. This study evaluated the normalized energy recovery (NER) based on the volume of wastewater treated (NERV) and chemical oxygen demand (COD) removal (NERCOD) using FA-MFCs with three anode spacing conditions and different flow rates (within a hydraulic retention time of 30 min). Generation of current was similar (11.7 ±â€¯0.5 mA) at different spacings; however, COD removal was affected by the flow rates. The NERV for both acetate and domestic wastewater showed good agreements with the flow rates in all anode spacing conditions. The NERCOD results were negatively correlated with the COD removal rates, independent of the anode spacing. The FA-MFCs yielded an NERCOD of 0.22 kWh/kg-COD from extremely low-strength domestic wastewater (150 mg-COD/L). The FA-MFC has a significant potential as an energy-sustainable wastewater treatment technology.


Subject(s)
Bioelectric Energy Sources , Wastewater , Biological Oxygen Demand Analysis , Electricity , Electrodes
20.
J Environ Manage ; 211: 36-41, 2018 Apr 01.
Article in English | MEDLINE | ID: mdl-29427929

ABSTRACT

Iron contamination in groundwater has attracted much attention from environmentalists and government agencies because it can cause many problems in human life and in industrial and agricultural activities when groundwater is directly used without any treatment. This study aims to investigate the electrochemical oxidation of Fe(II) to Fe(III) and recovery of insoluble Fe(III) using non-corrosive graphite electrode which serves as a controllable, low-cost, low maintenance and virtually unlimited electron acceptor for Fe(II) oxidation. The lab-scale results indicated that Fe(II) removal up to 100% was obtained at an applied voltage higher than 2 V. The Fe(II) removal efficiency was linearly increased with the increase of potential supply in the range of 1-4 V in the salinity 0.5%. The Fe(II) removal rate could no longer be enhanced at the applied potential higher than 8 V in the condition without salinity. The results from SEM-EDS and XRD revealed that Fe was recovered as FeOOH by conventional filtration with a recovery efficiency of 82.7-92.1%. The electrochemical Fe(II) removal might be an alternative for the conventional method of the in situ Fe removal from groundwater. Besides, the recovered FeOOH can be used as a raw material for environmental remediation and pigment industry.


Subject(s)
Groundwater/chemistry , Iron/chemistry , Water Pollutants, Chemical/chemistry , Electrodes , Environmental Restoration and Remediation , Iron/isolation & purification , Oxidation-Reduction , Water Pollutants, Chemical/isolation & purification
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