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1.
Am J Ophthalmol Case Rep ; 35: 102080, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38827999

RESUMO

Introduction: Calcification of hydrophilic intraocular lenses (IOL) is a rare complication following cataract surgery. Secondary calcification is described as due to host factors or changes in the IOL environment and uveitis, proliferative diabetic retinopathy and sequelae of ocular surgery are recognised potentiators. The impact of systemic connective tissue disease on IOL opacification is yet to described. Purpose: To describe the clinical presentation and management of a young patient, with a rare subtype of Ehlers-Danlos syndrome, who presented with secondary IOL calcification 14 years after primary IOL insertion. Observations: Floret-like lesions were observed on the IOL surface. Positive staining for calcification was observed with Alizarin red and von Kossa method on laboratory analysis. Conclusions and importance: Patients with systemic connective tissue disease, such as a subtype of Ehlers-Danlos, may present with secondary IOL calcification many years after primary lens insertion. This poses an additional consideration when implanting IOLs in these patients.Good visual acuity can be achieved with IOL exchange.

3.
J Acoust Soc Am ; 154(4): 1982-1995, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37782119

RESUMO

Harbour porpoises are visually inconspicuous but highly soniferous echolocating marine predators that are regularly studied using passive acoustic monitoring (PAM). PAM can provide quality data on animal abundance, human impact, habitat use, and behaviour. The probability of detecting porpoise clicks within a given area (P̂) is a key metric when interpreting PAM data. Estimates of P̂ can be used to determine the number of clicks per porpoise encounter that may have been missed on a PAM device, which, in turn, allows for the calculation of abundance and ideally non-biased comparison of acoustic data between habitats and time periods. However, P̂ is influenced by several factors, including the behaviour of the vocalising animal. Here, the common implicit assumption that changes in animal behaviour have a negligible effect on P̂ between different monitoring stations or across time is tested. Using a simulation-based approach informed by acoustic biologging data from 22 tagged harbour porpoises, it is demonstrated that porpoise behavioural states can have significant (up to 3× difference) effects on P̂. Consequently, the behavioural state of the animals must be considered in analysis of animal abundance to avoid substantial over- or underestimation of the true abundance, habitat use, or effects of human disturbance.


Assuntos
Ecolocação , Phocoena , Toninhas , Animais , Humanos , Ecossistema , Acústica
4.
New Dir Stud Leadersh ; 2022(173): 83-91, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35478342

RESUMO

This article outlines the diversity of engineering leadership programs by comparing origin stories, definitions, program structure, instructional strategies, research, and program evaluation approaches of seven North American engineering leadership programs.


Assuntos
Liderança , Humanos , Avaliação de Programas e Projetos de Saúde
5.
Sci Total Environ ; 828: 154283, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35247396

RESUMO

In Africa groundwater is the principal source of drinking water (https://washdata.org/) and has significant potential to improve food production as a source of irrigation water. Although volumes of stored groundwater are high when compared to surface water, not all the available groundwater is suitable for irrigation. One of the principal factors that limit the development of groundwater is salinity, but quantitative evidence regarding the scale of salinization in Africa has been lacking. This paper presents an initial analysis of the extent of groundwater salinization in Africa, bringing together groundwater salinity data (n = 12,255) from across the continent. In our dataset c.80% of the samples have electrical conductivity values less than 2000 µS/cm. Samples with high conductivity values of more than 2000 µS/cm are restricted to limited geological and climatic environments. The data reveals salinity does not affect the water security status of most countries in Africa. However, salinity compounds water insecurity issues in arid low groundwater recharge environments. The paper discusses the role of anthropogenic processes such as river valley water resources development, extensive groundwater pumping, inter-basin groundwater transfer, and irrigation in altering the salinity of groundwater bodies. The paper further elucidates the origin of groundwater salinity by critically reviewing the natural and human-induced factors that control the salinization of the various groundwater bodies across Africa. Existing case studies reveal several causes of salinization, including i) human-induced salinization, ii) climate and hydrological change-induced paleo groundwater salinity, iii) rock dissolution, and iv), saltwater encroachment.


Assuntos
Água Potável , Água Subterrânea , Poluentes Químicos da Água , Água Potável/análise , Monitoramento Ambiental , Água Subterrânea/análise , Humanos , Salinidade , Poluentes Químicos da Água/análise
6.
Proc Natl Acad Sci U S A ; 118(50)2021 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-34880135

RESUMO

Three types of variable lymphocyte receptor (VLR) genes, VLRA, VLRB, and VLRC, encode antigen recognition receptors in the extant jawless vertebrates, lampreys and hagfish. The somatically diversified repertoires of these VLRs are generated by serial stepwise copying of leucine-rich repeat (LRR) sequences into an incomplete germline VLR gene. Lymphocytes that express VLRA or VLRC are T cell-like, while VLRB-expressing cells are B cell-like. Here, we analyze the composition of the VLRB locus in different jawless vertebrates to elucidate its configuration and evolutionary modification. The incomplete germline VLRB genes of two hagfish species contain short noncoding intervening sequences, whereas germline VLRB genes in six representative lamprey species have much longer intervening sequences that exhibit notable genomic variation. Genomic clusters of potential LRR cassette donors, fragments of which are copied to complete VLRB gene assembly, are identified in Japanese lamprey and sea lamprey. In the sea lamprey, 428 LRR cassettes are located in five clusters spread over a total of 1.7 Mbp of chromosomal DNA. Preferential usage of the different donor cassettes for VLRB assemblage is characterized in our analysis, which reveals evolutionary modifications of the lamprey VLRB genes, elucidates the organization of the complex VLRB locus, and provides a comprehensive catalog of donor VLRB cassettes in sea lamprey and Japanese lamprey.


Assuntos
Anticorpos/metabolismo , Feiticeiras (Peixe)/genética , Lampreias/genética , Proteínas de Repetições Ricas em Leucina/metabolismo , Linfócitos/metabolismo , Filogenia , Animais , Variação Genética , Proteínas de Repetições Ricas em Leucina/genética , Especificidade da Espécie
8.
Artigo em Inglês | MEDLINE | ID: mdl-34035557

RESUMO

Förster resonance energy transfer (FRET) is a valuable tool for measuring molecular distances and the effects of biological processes such as cyclic nucleotide messenger signaling and protein localization. Most FRET techniques require two fluorescent proteins with overlapping excitation/emission spectral pairing to maximize detection sensitivity and FRET efficiency. FRET microscopy often utilizes differing peak intensities of the selected fluorophores measured through different optical filter sets to estimate the FRET index or efficiency. Microscopy platforms used to make these measurements include wide-field, laser scanning confocal, and fluorescence lifetime imaging. Each platform has associated advantages and disadvantages, such as speed, sensitivity, specificity, out-of-focus fluorescence, and Z-resolution. In this study, we report comparisons among multiple microscopy and spectral filtering platforms such as standard 2-filter FRET, emission-scanning hyperspectral imaging, and excitation-scanning hyperspectral imaging. Samples of human embryonic kidney (HEK293) cells were grown on laminin-coated 28 mm round gridded glass coverslips (10816, Ibidi, Fitchburg, Wisconsin) and transfected with adenovirus encoding a cAMP-sensing FRET probe composed of a FRET donor (Turquoise) and acceptor (Venus). Additionally, 3 FRET "controls" with fixed linker lengths between Turquoise and Venus proteins were used for inter-platform validation. Grid locations were logged, recorded with light micrographs, and used to ensure that whole-cell FRET was compared on a cell-by-cell basis among the different microscopy platforms. FRET efficiencies were also calculated and compared for each method. Preliminary results indicate that hyperspectral methods increase the signal-to-noise ratio compared to a standard 2-filter approach.

9.
Am J Physiol Regul Integr Comp Physiol ; 317(3): R379-R385, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31242019

RESUMO

In this study, myography was used to determine the effect of arterial size on nitric oxide (NO) vasodilatory mechanisms in the hindlimb vasculature of the toad Rhinella marina. Immunohistochemical analysis showed NO synthase (NOS) 1 immunoreactivity in perivascular nitrergic nerves in the iliac and sciatic arteries. Furthermore, NOS3 immunoreactivity was observed in the vascular smooth muscle of the sciatic artery, but not the endothelium. Acetylcholine (ACh) was used to facilitate intracellular Ca2+ signaling to activate vasodilatory pathways in the arteries. In the iliac artery, ACh-mediated vasodilation was abolished by blockade of the soluble guanylate cyclase pathway with the soluble guanylate cyclase inhibitor ODQ (1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one, 10-5 M) and blockade of the prostaglandin signaling pathway with indomethacin (10-5 M). Furthermore, disruption of the endothelium had no effect on the ACh-mediated vasodilation in the iliac artery, and generic inhibition of NOS with Nω-nitro-l-arginine (3 × 10-4 M) significantly inhibited the vasodilation, indicating NO signaling. In contrast to the iliac artery, ACh-mediated vasodilation of the sciatic artery had a significant endothelium-dependent component. Interestingly, the vasodilation was not significantly affected by Nω-nitro-l-arginine, but it was significantly inhibited by the specific NOS1 inhibitor N5-(1-imino-3-butenyl)-l-ornithine (vinyl-l-NIO, 10-4 M). ODQ mostly inhibited the ACh-mediated vasodilation. In addition, indomethacin also significantly inhibited the ACh-mediated vasodilation, indicating a role for prostaglandins in the sciatic artery. This study found that the mechanisms of vasodilation in the hindlimb vasculature of R. marina vary with vessel size and that the endothelium is involved in vasodilation in the smaller sciatic artery.


Assuntos
Artérias/fisiologia , Membro Posterior/irrigação sanguínea , Vasodilatação/fisiologia , Animais , Artérias/anatomia & histologia , Bufo marinus , Feminino , Humanos , Imuno-Histoquímica , Masculino , Óxido Nítrico Sintase/química , Óxido Nítrico Sintase/metabolismo , Nitroarginina/farmacologia , Oxidiazóis , Quinoxalinas , Transdução de Sinais
10.
BMJ Open Ophthalmol ; 4(1): e000227, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30997401

RESUMO

OBJECTIVE: During phacoemulsification, the corneal endothelium is protected by an ophthalmic viscosurgical device (OVD). In this in vitro study, we assessed six different OVDs for their effectiveness in protecting the corneal endothelium. METHODS AND ANALYSIS: Phacoemulsification was performed in cadaver eyes of young pigs. Five syringe units of six different OVDs were tested (Healon EndoCoat, Viscoat, Methylvisc, Healon, Healon GV, ProVisc). After surgery, the area of endothelium coated with OVD was determined in relation to the total endothelial surface. Additionally, an endothelial cell count was obtained. As a control, an endothelial cell count was obtained from freshly trephined corneas. Statistical analysis was performed using the Mann-Whitney U test and the Spearman correlation. RESULTS: The least postoperative endothelial coating and cell count were observed in the cohesive OVDs while the dispersive OVDs showed statistically significant higher values. Healon EndoCoat and Viscoat yielded a coating area of 86 (85-92)% and 85 (85-90)%, respectively. Endothelial cell count was highest in the two dispersive groups with 4065 (3928-4088) cells/mm2 (Methylvisc) and 4032 (4015-4115) cells/mm2 (Viscoat). Endothelial coating area and endothelial cell count correlated statistically significantly. CONCLUSION: Dispersive OVDs from this study showed greater adherence to the endothelial surface than the cohesive ones. Furthermore, postoperative endothelial cell counts of corneas treated with dispersive OVDs were higher than of corneas treated with cohesive OVDs. Our in vitro results suggest that dispersive OVDs protect the corneal endothelium better during phacoemulsification than cohesive OVDs.

12.
Cytokine Growth Factor Rev ; 41: 18-27, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29680500

RESUMO

Epidermal growth factor receptor (EGFR) is a known target in cancer therapy and targeting the receptor has proven to be extremely successful in treating cancers that are dependent on EGFR signaling. To that effect, targeted therapies to EGFR such as Cetuximab, Panitumumab-monoclonal antibodies and Gefitinib, Erlotinib-tyrosine kinase inhibitors have had success in therapeutic scenarios. However, the development of resistance to these drugs makes it necessary to combine anti- EGFR therapies with other inhibitors, so that resistance can be overcome by the targeting of alternate signaling pathways. On the other hand, components of the inflammatory pathway, within and around a tumor, provide a conducive environment for tumor growth by supplying numerous cytokines and chemokines that foster carcinogenesis. Interleukin 6 (IL-6) is one such cytokine that is found to be associated with inflammation-driven cancers and which also plays a crucial role in acquired resistance to anti-EGFR drugs. The EGFR and IL-6 signaling pathways crosstalk in multiple ways, through various mediators and downstream signaling pathways driving resistance and hence co-targeting them has potential for future cancer treatments. Here we provide an overview on the crosstalk between the EGFR and IL-6 pathways, and discuss how co-targeting these two pathways could be a promising combination therapy of the future.


Assuntos
Carcinogênese/metabolismo , Receptores ErbB/metabolismo , Interleucina-6/metabolismo , Neoplasias/metabolismo , Transdução de Sinais/fisiologia , Animais , Humanos , Inflamação/metabolismo
13.
Am J Physiol Regul Integr Comp Physiol ; 314(2): R242-R251, 2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-29046317

RESUMO

Nitrite ([Formula: see text]) causes vasodilation in mammals due to the formation of (nitric oxide) NO by endogenous [Formula: see text] reduction in the vascular wall. In this study, we determined if a similar mechanism operates in amphibians. Dual-wire myography of the iliac artery from Rhinella marina showed that applied [Formula: see text] caused a concentration-dependent vasodilation in normoxia (21% O2; EC50: 438 µM). Hypoxia (0.63% O2) significantly increased the maximal dilation to [Formula: see text] by 5% ( P = 0.0398). The addition of oxyhemoglobin significantly increased the EC50 ( P = 0.0144; EC50: 2,236 µM) but did not affect the maximal vasodilation. In contrast, partially deoxygenated hemoglobin (90% desaturation) did not affect the EC50 ( P = 0.1189) but significantly ( P = 0.0012) increased the maximal dilation to [Formula: see text] by 11%. The soluble guanylyl cyclase inhibitor 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ) completely abolished the response to [Formula: see text] ( P < 0.0001), and of the nitric oxide synthase inhibitors, only N5-(1-imino-3-butenyl)-l-ornithine (vinyl-l-NIO; P = 0.0028) significantly reduced the [Formula: see text] vasodilation. The xanthine oxidoreductase inhibitor allopurinol ( P = 0.927), the nitric oxide-scavenger 2-(4-carboxyphenyl)-4,5-dihydro-4,4,5,5-tetramethyl-1H-imidazolyl-1-oxy-3-oxide (C-PTIO; P = 0.478), and disruption of the endothelium ( P = 0.094) did not affect the [Formula: see text] vasodilation. Incubation of iliac arteries with 1 mM [Formula: see text] did not a cause a change in the cGMP concentration (P = 0.407). Plasma [Formula: see text] was found to be 0.86 ± 0.20 µmol/l, while nitrate ([Formula: see text]) was 19.55 ± 2.55 µmol/l. Both cygb and ngb mRNAs were expressed in the iliac artery, and it is possible that these globins facilitate [Formula: see text] reduction in hypoxia. In addition, [Formula: see text] intracellular disproportionation processes could be important in the generation of NO from [Formula: see text].


Assuntos
Artéria Ilíaca/efeitos dos fármacos , Nitrito de Sódio/farmacologia , Vasodilatação/efeitos dos fármacos , Vasodilatadores/farmacologia , Proteínas de Anfíbios/genética , Proteínas de Anfíbios/metabolismo , Animais , Bufo marinus , Citoglobina/genética , Citoglobina/metabolismo , Feminino , Hemoglobinas/metabolismo , Artéria Ilíaca/metabolismo , Técnicas In Vitro , Masculino , Neuroglobina/genética , Neuroglobina/metabolismo , Óxido Nítrico/metabolismo , Nitrito Redutases/metabolismo , Oxirredução , Oxiemoglobinas/metabolismo , Nitrito de Sódio/metabolismo , Vasodilatadores/metabolismo
15.
J Occup Health ; 59(4): 313-326, 2017 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-28539534

RESUMO

BACKGROUND: Mount Oyama, on the Japanese island of Miyakejima, began erupting in June 2000, necessitating the evacuation of 3,000 island residents. Volcanic gas emissions, primarily consisting of sulfur dioxide (SO2), gradually decreased and residents returned to the island after the evacuation order was lifted in February 2005. OBJECTIVES: To assess the exposure-effect and exposure-response relationships between SO2 exposure and effects on respiratory system in adult Miyakejima residents. METHOD: Health checkups focusing on pulmonary function and respiratory/irritative symptoms were conducted six times every November from 2006 to 2011. The study population comprised 168 subjects who underwent all health checkups. SO2 concentrations were measured at six fixed monitoring stations in inhabitable areas. RESULT: Based on the annual mean SO2 concentration, inhabitable areas were classified into three categories; namely, lower (L), higher (H-1), and highest (H-2) areas. Average SO2 concentrations (ppb) during 3 months prior to each health checkup dropped from 11.3 to 3.29, 32.2 to 13.4 and 75.1 to 12.6 from 2006 to 2010/2011 in L, H-1, and H-2. No significant declines in pulmonary function were observed in all areas. However, prevalence of subjective symptoms such as "Cough," "Irritation and/or pain in throat," "Irritation, runny nose, and/or nasal sniffles," and "Irritation and/or pain in the eyes," dependently increased on SO2 concentration. Odds ratios were statistically significant at approximately 70 ppb of SO2 or above. CONCLUSION: Adult residents of Miyakejima island showed no deterioration in pulmonary function at SO2 levels, but complained of respiratory/irritative symptoms in an SO2 concentration-dependent manner.


Assuntos
Poluentes Atmosféricos/efeitos adversos , Poluição do Ar/efeitos adversos , Exposição Ambiental/efeitos adversos , Doenças Respiratórias/induzido quimicamente , Doenças Respiratórias/epidemiologia , Dióxido de Enxofre/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Exposição Ambiental/análise , Monitoramento Ambiental , Feminino , Humanos , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Testes de Função Respiratória , Sistema Respiratório , Dióxido de Enxofre/análise , Erupções Vulcânicas/efeitos adversos
16.
Gen Comp Endocrinol ; 244: 201-208, 2017 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-27102941

RESUMO

Water deprivation of the Spinifex hopping mouse, Notomys alexis, induced a biphasic pattern of food intake with an initial hypophagia that was followed by an increased, and then sustained food intake. The mice lost approximately 20% of their body mass and there was a loss of white adipose tissue. Stomach ghrelin mRNA was significantly higher at day 2 of water deprivation but then returned to the same levels as water-replete (day 0) mice for the duration of the experiment. Plasma ghrelin was unaffected by water deprivation except at day 10 where it was significantly increased. Plasma leptin levels decreased at day 2 and day 5 of water deprivation, and then increased significantly by the end of the water deprivation period. Water deprivation caused a significant decrease in skeletal muscle leptin mRNA expression at days 2 and 5, but then it returned to day 0 levels by day 29. In the hypothalamus, water deprivation caused a significant up-regulation in both ghrelin and neuropeptide Y mRNA expression, respectively. In contrast, hypothalamic GHSR1a mRNA expression was significantly down-regulated. A significant increase in LepRb mRNA expression was observed at days 17 and 29 of water deprivation. This study demonstrated that the sustained food intake in N. alexis during water deprivation was uncoupled from peripheral appetite-regulating signals, and that the hypothalamus appears to play an important role in regulating food intake; this may contribute to the maintenance of fluid balance in the absence of free water.


Assuntos
Regulação do Apetite/fisiologia , Grelina/metabolismo , Leptina/metabolismo , Murinae/fisiologia , Animais , Apetite , Austrália , DNA Complementar/genética , Ingestão de Alimentos/fisiologia , Regulação da Expressão Gênica/fisiologia , Hipotálamo/metabolismo , Rim/metabolismo , Camundongos , Neuropeptídeo Y/genética , RNA Mensageiro/genética , Regulação para Cima , Privação de Água
17.
Cell Tissue Res ; 366(3): 679-692, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27543051

RESUMO

In mammals, nitric oxide (NO) produced by nitric oxide synthase 3 (NOS3) localised in vascular endothelial cells is an important vasodilator but the presence of NOS3 in the endothelium of amphibians has been concluded to be absent, based on physiological studies. In this study, a nos3 cDNA was sequenced from the toad, Rhinella marina. The open reading frame of R. marina nos3 encoded an 1170 amino acid protein that showed 81 % sequence identity to the recently cloned Xenopus tropicalis nos3. Rhinella marina nos3 mRNA was expressed in a range of tissues and in the dorsal aorta and pulmonary, mesenteric, iliac and gastrocnemius arteries. Furthermore, nos3 mRNA was expressed in the aorta of Xenopus laevis and X. tropicalis. Quantitative real-time PCR showed that removal of the endothelium of the lateral aorta of R. marina significantly reduced the expression of nos3 mRNA compared to control aorta with the endothelium intact. However, in situ hybridisation was not able to detect any nos3 mRNA in the dorsal aorta of R. marina. Immunohistochemistry using a homologous R. marina NOS3 antibody showed immunoreactivity (IR) within the basal region of many endothelial cells of the dorsal aorta and iliac artery. NOS3-IR was also observed in the proximal tubules and collecting ducts of the kidney but not within the capillaries of the glomeruli. This is the first study to demonstrate that vascular endothelial cells of an amphibian express NOS3.


Assuntos
Anfíbios/metabolismo , Vasos Sanguíneos/enzimologia , Óxido Nítrico Sintase Tipo III/metabolismo , Sequência de Aminoácidos , Animais , Northern Blotting , Feminino , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Hibridização In Situ , Masculino , Óxido Nítrico Sintase Tipo III/química , Óxido Nítrico Sintase Tipo III/genética , Especificidade de Órgãos/genética , Filogenia , Reação em Cadeia da Polimerase , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Alinhamento de Sequência , Análise de Sequência de Proteína
18.
Am J Physiol Regul Integr Comp Physiol ; 311(1): R66-78, 2016 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-27122370

RESUMO

Most vertebrates, including cartilaginous fishes, maintain their plasma SO4 (2-) concentration ([SO4 (2-)]) within a narrow range of 0.2-1 mM. As seawater has a [SO4 (2-)] about 40 times higher than that of the plasma, SO4 (2-) excretion is the major role of kidneys in marine teleost fishes. It has been suggested that cartilaginous fishes also excrete excess SO4 (2-) via the kidney. However, little is known about the underlying mechanisms for SO4 (2-) transport in cartilaginous fish, largely due to the extraordinarily elaborate four-loop configuration of the nephron, which consists of at least 10 morphologically distinguishable segments. In the present study, we determined cDNA sequences from the kidney of holocephalan elephant fish (Callorhinchus milii) that encoded solute carrier family 26 member 1 (Slc26a1) and member 6 (Slc26a6), which are SO4 (2-) transporters that are expressed in mammalian and teleost kidneys. Elephant fish Slc26a1 (cmSlc26a1) and cmSlc26a6 mRNAs were coexpressed in the proximal II (PII) segment of the nephron, which comprises the second loop in the sinus zone. Functional analyses using Xenopus oocytes and the results of immunohistochemistry revealed that cmSlc26a1 is a basolaterally located electroneutral SO4 (2-) transporter, while cmSlc26a6 is an apically located, electrogenic Cl(-)/SO4 (2-) exchanger. In addition, we found that both cmSlc26a1 and cmSlc26a6 were abundantly expressed in the kidney of embryos; SO4 (2-) was concentrated in a bladder-like structure of elephant fish embryos. Our results demonstrated that the PII segment of the nephron contributes to the secretion of excess SO4 (2-) by the kidney of elephant fish. Possible mechanisms for SO4 (2-) secretion in the PII segment are discussed.


Assuntos
Peixe Elétrico/metabolismo , Túbulos Renais Proximais/metabolismo , Rim/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Sulfatos/metabolismo , Sequência de Aminoácidos , Animais , DNA Complementar/genética , Embrião não Mamífero/metabolismo , Proteínas de Peixes/metabolismo , Néfrons/metabolismo , Oócitos/metabolismo , Distribuição Tecidual , Xenopus
19.
PLoS One ; 11(3): e0150770, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26943160

RESUMO

Rainbow trout, Oncorhynchus mykiss, are intensively cultured globally. Understanding their requirement for long-chain polyunsaturated fatty acids (LC-PUFA) and the biochemistry of the enzymes and biosynthetic pathways required for fatty acid synthesis is important and highly relevant in current aquaculture. Most gnathostome vertebrates have two fatty acid desaturase (fads) genes with known functions in LC-PUFA biosynthesis and termed fads1 and fads2. However, teleost fish have exclusively fads2 genes. In rainbow trout, a fads2 cDNA had been previously cloned and found to encode an enzyme with Δ6 desaturase activity. In the present study, a second fads2 cDNA was cloned from the liver of rainbow trout and termed fads2b. The full-length mRNA contained 1578 nucleotides with an open reading frame of 1365 nucleotides that encoded a 454 amino acid protein with a predicted molecular weight of 52.48 kDa. The predicted Fads2b protein had the characteristic traits of the microsomal Fads family, including an N-terminal cytochrome b5 domain containing the heme-binding motif (HPPG), histidine boxes (HDXGH, HFQHH and QIEHH) and three transmembrane regions. The fads2b was expressed predominantly in the brain, liver, intestine and pyloric caeca. Expression of the fasd2b in yeast generated a protein that was found to specifically convert eicosatetraenoic acid (20:4n-3) to eicosapentaenoic acid (20:5n-3), and therefore functioned as a Δ5 desaturase. Therefore, rainbow trout have two fads2 genes that encode proteins with Δ5 and Δ6 desaturase activities, respectively, which enable this species to perform all the desaturation steps required for the biosynthesis of LC-PUFA from C18 precursors.


Assuntos
Ácidos Graxos Dessaturases/genética , Ácidos Graxos Dessaturases/isolamento & purificação , Oncorhynchus mykiss/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , DNA Complementar/genética , Ácidos Graxos Dessaturases/química , Ácidos Graxos Dessaturases/metabolismo , Perfilação da Expressão Gênica , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase em Tempo Real , Saccharomyces cerevisiae/metabolismo , Alinhamento de Sequência , Análise de Sequência de RNA
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