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1.
bioRxiv ; 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38895332

RESUMEN

Background: Premature infants often experience frequent hypoxic episodes due to immaturity of respiratory control that may result in disturbances of gray and white matter development and long-term cognitive and behavioral abnormalities. We hypothesize that neonatal intermittent hypoxia alters cortical maturation of excitatory and inhibitory circuits that can be detected early with functional MRI. Methods: C57BL/6 mouse pups were exposed to an intermittent hypoxia (IH) regimen consisting of 12 to 20 daily hypoxic episodes of 5% oxygen exposure for 2 min at 37C from P3 to P7, followed by MRI at P12 and electrophysiological recordings in cortical slices and in vivo at several time points between P7 and P13. Behavioral tests were conducted at P41-P50 to assess animal activity and motor learning. Results: Adult mice after neonatal IH exhibited hyperactivity in open field test and impaired motor learning in complex wheel tasks. Patch clamp and evoked field potential electrophysiology revealed increased glutamatergic transmission accompanied by elevation of tonic inhibition. A decreased synaptic inhibitory drive was evidenced by miniature IPSC frequency on pyramidal cells, multi-unit activity recording in vivo in the motor cortex with selective GABA A receptor inhibitor picrotoxin injection, as well as by the decreased interneuron density at P13. There was also an increased tonic depolarizing effect of picrotoxin after IH on principal cells' membrane potential on patch clamp and direct current potential in extracellular recordings. The amplitude of low-frequency fluctuation on resting-state fMRI was larger, with a larger increase after picrotoxin injection in the IH group. Conclusions: Increased excitatory glutamatergic transmission, decreased numbers, and activity of inhibitory interneurons after neonatal IH may affect the maturation of connectivity in cortical networks, resulting in long-term cognitive and behavioral changes, including impaired motor learning and hyperactivity. Functional MRI reveals increased intrinsic connectivity in the sensorimotor cortex, suggesting neuronal dysfunction in cortical maturation after neonatal IH. The increased tonic inhibition, presumably due to tonic extrasynaptic GABA receptor drive, may be compensatory to the elevated excitatory glutamatergic transmission.

2.
Gut Microbes ; 16(1): 2333808, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38533575

RESUMEN

Premature infants lack a normal intestinal microbial community and also at risk of perinatal hypoxic-ischemic (HI) brain injury, which is considered to be one of the major factors for motor, sensory, and cognitive deficits. We hypothesized that neonatal gut microbiota composition modulated the immune reaction and severity of neonatal H-I brain injury. Neonatal C57BL/6J mouse pups were exposed to H-I protocol consisting of permanent left carotid artery ligation, followed by 8% hypoxia for 60 min. Microbial manipulation groups included 1) antibiotic treatment, E18 (maternal) to P5; 2) antibiotic treatment E18 to P5 + E. coli gavage; 3) antibiotic treatment E18 to P5 + B. infantis gavage; and 4) saline to pups with dams getting fresh water. The extent of brain injury and recovery was measured on MRI. Edematous injury volume was significantly higher in E. coli group than that in B. infantis group and in fresh water group. Gene expression in brains of pro-inflammatory cytokines (IL1ß, IL6, IL2, TNF-α and toll-like receptors 2-6) were elevated to a greater extent in the E. coli group at P10, no injury, and at P13, 72 hours after H-I relative to sham control and B. infantis groups. Significant effects of microbiome and brain injury and interaction of these factors were found in abundance of major phyla. The neuroinflammatory response and brain injury after neonatal hypoxia-ischemia are affected by intestinal microbiota, providing opportunities for therapeutic intervention through targeting the early colonization and development of the gut microbiota.


Asunto(s)
Lesiones Encefálicas , Microbioma Gastrointestinal , Hipoxia-Isquemia Encefálica , Animales , Ratas , Ratones , Recién Nacido , Embarazo , Femenino , Humanos , Animales Recién Nacidos , Ratas Wistar , Escherichia coli , Ratones Endogámicos C57BL , Lesiones Encefálicas/metabolismo , Isquemia/metabolismo , Hipoxia-Isquemia Encefálica/tratamiento farmacológico , Hipoxia-Isquemia Encefálica/metabolismo , Encéfalo/metabolismo , Hipoxia/metabolismo , Antibacterianos/farmacología
3.
J Exp Zool A Ecol Integr Physiol ; 339(9): 887-897, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37522484

RESUMEN

Ocypode quadrata, a Ghost crab species found along the western Atlantic coast, is considered a bioindicator of anthropogenic impact on sandy beaches. Ghost Crabbing, a touristic activity in which ghost crabs are chased just for fun, is a potentially threatening activity for this crab. In crustaceans, metabolites such as glucose and lactate, and the gene expression of crustacean hyperglycemic hormone (CHH) and heat shock proteins (HSPs) increase when the animals are exposed to several types of stress, including alterations in temperature, salinity, or exposure to xenobiotics. This work was developed to identify if being chased by humans would affect these markers of stress in this species of crab. The effects of chasing stress on hemolymph and tissue metabolites and the gene expression levels of CHH and HSP70 were investigated. The levels of lactate in the hemolymph of stressed crabs were six times higher than those of control crabs immediately after chasing and decreased progressively during recovery, indicating an active anaerobic metabolism during the stress. On the contrary, glucose levels in the hemolymph of the stressed crabs increased progressively from 30 to 60 min after chasing, indicating an inverse correlation between glucose and lactate and the conversion of lactate to glucose by gluconeogenesis. In stressed crabs, the levels of triglycerides in the hemolymph decreased 30 min after chasing, while the opposite tended to occur in the hepatopancreas, indicating that during recovery, the crabs use triglycerides as energy source to sustain aerobic metabolism. Finally, this study demonstrates that ghost crabs are stressed by minimum human contact and that "ghost crabbing" must not be encouraged as a tourist activity.


Asunto(s)
Braquiuros , Humanos , Animales , Braquiuros/fisiología , Glucosa/metabolismo , Triglicéridos , Lactatos
4.
Mol Cell Neurosci ; 126: 103864, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37268283

RESUMEN

Oxygen deprivation is one of the main causes of morbidity and mortality in newborns, occurring with a higher prevalence in preterm infants, reaching 20 % to 50 % mortality in newborns in the perinatal period. When they survive, 25 % exhibit neuropsychological pathologies, such as learning difficulties, epilepsy, and cerebral palsy. White matter injury is one of the main features found in oxygen deprivation injury, which can lead to long-term functional impairments, including cognitive delay and motor deficits. The myelin sheath accounts for much of the white matter in the brain by surrounding axons and enabling the efficient conduction of action potentials. Mature oligodendrocytes, which synthesize and maintain myelination, also comprise a significant proportion of the brain's white matter. In recent years, oligodendrocytes and the myelination process have become potential therapeutic targets to minimize the effects of oxygen deprivation on the central nervous system. Moreover, evidence indicate that neuroinflammation and apoptotic pathways activated during oxygen deprivation may be influenced by sexual dimorphism. To summarize the most recent research about the impact of sexual dimorphism on the neuroinflammatory state and white matter injury after oxygen deprivation, this review presents an overview of the oligodendrocyte lineage development and myelination, the impact of oxygen deprivation and neuroinflammation on oligodendrocytes in neurodevelopmental disorders, and recent reports about sexual dimorphism regarding the neuroinflammation and white matter injury after neonatal oxygen deprivation.


Asunto(s)
Lesiones Encefálicas , Sustancia Blanca , Recién Nacido , Humanos , Embarazo , Femenino , Oxígeno/metabolismo , Enfermedades Neuroinflamatorias , Recien Nacido Prematuro , Vaina de Mielina/metabolismo , Encéfalo/metabolismo , Oligodendroglía/metabolismo , Sustancia Blanca/metabolismo , Lesiones Encefálicas/metabolismo
5.
Metab Brain Dis ; 37(7): 2315-2329, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35778625

RESUMEN

Therapeutic hypothermia (TH) is the standard treatment for neonatal hypoxia-ischemia (HI) with a time window limited up to 6 h post injury. However, influence of sexual dimorphism in the therapeutic window for TH has not yet been elucidated in animal models of HI. Therefore, the aim of this study was to investigate the most effective time window to start TH in male and female rats submitted to neonatal HI. Wistar rats (P7) were divided into the following groups: NAÏVE and SHAM (control groups), HI (submitted to HI) and TH (submitted to HI and TH; 32ºC for 5 h). TH was started at 2 h (TH-2 h group), 4 h (TH-4 h group), or 6 h (TH-6 h group) after HI. At P14, animals were subjected to behavioural tests, volume of lesion and reactive astrogliosis assessments. Male and female rats from the TH-2 h group showed reduction in the latency of behavioral tests, and decrease in volume of lesion and intensity of GFAP immunofluorescence. TH-2 h females also showed reduction of degenerative cells and morphological changes in astrocytes. Interestingly, females from the TH-6 h group showed an increase in volume of lesion and in number of degenerative hippocampal cells, associated with worse behavioral performance. Together, these results indicate that TH neuroprotection is time- and sex-dependent. Moreover, TH started later (6 h) can worsen volume of brain lesion in females. These data indicate the need to develop specific therapeutic protocols for each sex and reinforce the importance of early onset of the hypothermic treatment.


Asunto(s)
Hipotermia Inducida , Hipoxia-Isquemia Encefálica , Animales , Masculino , Femenino , Ratas , Hipoxia-Isquemia Encefálica/terapia , Hipoxia-Isquemia Encefálica/patología , Gliosis/terapia , Gliosis/patología , Ratas Wistar , Animales Recién Nacidos , Encéfalo , Isquemia/patología , Isquemia/terapia , Modelos Animales de Enfermedad
6.
Behav Brain Res ; 430: 113935, 2022 07 26.
Artículo en Inglés | MEDLINE | ID: mdl-35605797

RESUMEN

Chronic cerebral hypoperfusion leads to neuronal loss in the hippocampus and spatial memory impairments. Physical exercise is known to prevent cognitive deficits in animal models; and there is evidence of sex differences in behavioral neuroprotective approaches. The aim of present study was to investigate the effects of acrobatic training in male and female rats submitted to chronic cerebral hypoperfusion. Males and females rats underwent 2VO (two-vessel occlusion) surgery and were randomly allocated into 4 groups of males and 4 groups of females, as follows: 2VO acrobatic, 2VO sedentary, Sham acrobatic and Sham sedentary. The acrobatic training started 45 days after surgery and lasted 4 weeks; animals were then submitted to object recognition and water maze testing. Brain samples were collected for histological and morphological assessment and flow cytometry. 2VO causes cognitive impairments and acrobatic training prevented spatial memory deficits assessed in the water maze, mainly for females. Morphological analysis showed that 2VO animals had less NeuN labeling and acrobatic training prevented it. Increased number of GFAP positive cells was observerd in females; moreover, males had more branched astrocytes and acrobatic training prevented the branching after 2VO. Flow cytometry showed higher mitochondrial potential in trained animals and more reactive oxygen species production in males. Acrobatic training promoted neuronal survival and improved mitochondrial function in both sexes, and influenced the glial scar in a sex-dependent manner, associated to greater cognitive benefit to females after chronic cerebral hypoperfusion.


Asunto(s)
Isquemia Encefálica , Memoria Espacial , Animales , Femenino , Masculino , Ratas , Astrocitos/patología , Isquemia Encefálica/patología , Cicatriz/patología , Modelos Animales de Enfermedad , Hipocampo , Aprendizaje por Laberinto , Memoria Espacial/fisiología
7.
Gen Comp Endocrinol ; 302: 113661, 2021 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-33220302

RESUMEN

To test the hypothesis of conservation of stanniocalcin 1 and 2 (STC-1; STC-2) metabolic functions in vertebrates, we performed an in vitro study to determine if these hormones are implicated in regulation of the gluconeogenesis pathway, glycogen synthesis, and 14C-glucose conversion to 14CO2 in livers from fed and fasting rats (Rattus norvegicus). Stc1 and Stc2 gene expressions increased in the liver after fasting. STC-1 participated in the regulation of the hepatic gluconeogenesis pathway in rats when the precursor was 14C-lactate. STC-2 demonstrated variational signaling on rat hepatic gluconeogenesis activity and Pck1 gene expression, decreasing levels in the fed state when the substrate was 14C-alanine and increasing levels during fasting when the substrate was 14C-lactate. At the concentrations used in this study, STC-1 and STC-2 did not affect glycogen concentration and synthesis from 14C-glucose or 14C-glucose conversion to 14CO2 in the livers from fed or fasting rats. These findings highlight the role of stanniocalcins in the hepatic gluconeogenesis pathway in mammals and confirm the conservation of STC-1 and STC-2 metabolic functions in the vertebrates.


Asunto(s)
Ayuno , Gluconeogénesis , Animales , Glucosa/metabolismo , Glicoproteínas , Homeostasis , Hormonas/metabolismo , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Hígado/metabolismo , Ratas
8.
Neuroscience ; 448: 191-205, 2020 11 10.
Artículo en Inglés | MEDLINE | ID: mdl-32905840

RESUMEN

Neonatal hypoxic-ischemic encephalopathy is a major cause of mortality and disability in newborns and the only standard approach for treating this condition is therapeutic hypothermia, which shows some limitations. Thus, putative neuroprotective agents have been tested in animal models. The present study evaluated the administration of lactate, a potential energy substrate of the central nervous system (CNS) in an animal model of hypoxia-ischemia (HI), that mimics in neonatal rats the brain damage observed in human newborns. Seven-day-old (P7) male and female Wistar rats underwent permanent common right carotid occlusion combined with an exposition to a hypoxic atmosphere (8% oxygen) for 60 min. Animals were assigned to four experimental groups: HI, HI + LAC, SHAM, SHAM + LAC. Lactate was administered intraperitoneally 30 min and 2 h after hypoxia in HI + LAC and SHAM + LAC groups. HI and SHAM groups received vehicle at the same time points. The volume of brain lesion was evaluated in P9. Animals underwent behavioral assessments: negative geotaxis, righting reflex (P8 and P14), and cylinder test (P20). Lactate administration reduced the volume of brain lesion and improved behavioral parameters after HI in both sexes. Thus, lactate administration could be a neuroprotective strategy for the treatment of neonatal HI, a disorder still affecting a significant percentage of human newborns.


Asunto(s)
Lesiones Encefálicas , Hipoxia-Isquemia Encefálica , Fármacos Neuroprotectores , Animales , Animales Recién Nacidos , Encéfalo , Modelos Animales de Enfermedad , Femenino , Hipoxia , Hipoxia-Isquemia Encefálica/tratamiento farmacológico , Isquemia , Ácido Láctico , Masculino , Ratas , Ratas Wistar
9.
Life Sci ; 256: 117922, 2020 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-32522569

RESUMEN

To test the hypothesis of STC-1 participation in maintenance of glucose homeostasis in fed and fasting (48 h) rats, we investigated that this hormone may be implicated in the regulation of renal gluconeogenesis pathway from lactate and lactate oxidation in renal cortex and medulla. Our results demonstrate the hSTC-1 role on lactate metabolism in the renal cortex and medulla from fed and fasting rats. hSTC-1 increased the gluconeogenesis activity in fed state in renal cortex, and this increase was induced by raise in Pck1 gene expression. In fasting animals hSTC-1 increase the renal medulla gluconeogenesis activity, but Pck1 gene expression was not alter. The stimulatory effect of hSTC-1 on 14C-lactate oxidation occurred only in the renal cortex from fed rats. These findings show the hSTC-1 contribution to lactate homeostasis and supplies glucose to other tissues. This response may represent a strategy of action of STC-1 in response to fasting stress as postulated by different authors. On the other hand, hSTC-1 acts downstream of adenylcyclase pathway, decreasing the gluconeogenesis activity induced by cAMP intracellular increase or stimulating the phosphodiesterase activity in the renal cortex. However, no hSTC-1 effect on 14C-lactate oxidation was found after increase in the intracellular cAMP. The findings also revealed that the renal cortex and medulla respond differently to hSTC-1, possibly due to the higher level of STC-1 gene expression in inner renal medulla than in renal cortex.


Asunto(s)
Gluconeogénesis/efectos de los fármacos , Glicoproteínas/metabolismo , Hormonas/metabolismo , Riñón/metabolismo , Lactatos/metabolismo , Proteínas Recombinantes/metabolismo , Adenilil Ciclasas/metabolismo , Animales , Dióxido de Carbono/metabolismo , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Regulación de la Expresión Génica , Glucosa/metabolismo , Glicoproteínas/genética , Hormonas/genética , Humanos , Corteza Renal/metabolismo , Médula Renal/metabolismo , Masculino , Oxidación-Reducción , Hidrolasas Diéster Fosfóricas/metabolismo , Ratas , Ratas Wistar , Proteínas Recombinantes/genética , Transducción de Señal
10.
Cell Mol Neurobiol ; 40(8): 1417-1428, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32170571

RESUMEN

Neonatal hypoxia-ischemia (HI) is the leading cause of mortality and morbidity in newborns, occurring in approximately 2% of live births. Neuroprotective actions of progesterone (PROG) have already been described in animal models of brain lesions. However, PROG actions on neonates are still controversial. Here, we treated male Wistar rats exposed to HI with PROG. Five experimental groups were defined (n = 6/group) according to the scheme of PROG administration (10 mg/kg): SHAM (animals submitted to a fictitious surgery, without ischemia induction, and maintained under normoxia), HI (animals undergoing HI), BEFORE (animals undergoing HI and receiving PROG immediately before HI), AFTER (animals undergoing HI and receiving PROG at 6 and 24 h after HI) and BEFORE/AFTER (animals undergoing HI and receiving PROG immediately before and 6 and 24 h after HI). At P14 (7 days following HI), the volumes of lesion of the cerebral hemisphere and the hippocampus ipsilateral to the cerebral ischemia were evaluated, along with p-Akt, cleaved caspase-3 and GFAP expression in the hippocampus. PROG reduces the loss of brain tissue caused by HI. Moreover, when administered after HI, PROG was able to increase p-Akt expression and reduce both cleaved caspase-3 and GFAP expression in the hippocampus. In summary, it was possible to observe a neuroprotective action of PROG on the brain of neonatal animals exposed to experimental HI. This is the first study suggesting PROG-dependent Akt activation is able to regulate negatively cleaved caspase-3 and GFAP expression protecting neonatal hypoxic-ischemic brain tissue from apoptosis and reactive gliosis.


Asunto(s)
Encéfalo/efectos de los fármacos , Hipoxia-Isquemia Encefálica/tratamiento farmacológico , Isquemia/metabolismo , Fármacos Neuroprotectores/farmacología , Progesterona/farmacología , Animales , Animales Recién Nacidos , Encéfalo/metabolismo , Hipoxia/tratamiento farmacológico , Hipoxia/metabolismo , Hipoxia-Isquemia Encefálica/metabolismo , Hipoxia-Isquemia Encefálica/patología , Isquemia/tratamiento farmacológico , Masculino , Ratas Wistar
11.
Int J Dev Neurosci ; 79: 86-95, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31693927

RESUMEN

INTRODUCTION: Neonatal Hypoxia-Ischemia (HI) is a major cause of morbidity and mortality, and is frequently associated with short and long-term neurologic and cognitive impairments. The HI injury causes mitochondrial damage leading to increased production of reactive oxygen species (ROS). Phytoestrogens are non-steroidal plant substances structurally and functionally similar to estrogen. Coumestrol is a potent isoflavonoid with a protective effect against ischemic brain damage in adult rats. Our aim was to determine if coumestrol treatment following neonatal HI attenuates the long-term cognitive deficits induced by neonatal HI, as well as to investigate one possible mechanism underlying its potential effect. METHODS: On the 7th postnatal day, male Wistar rats were submitted to the Levine-Rice HI model. Intraperitoneal injections of 20 mg/kg of coumestrol, or vehicle, were administered immediately pre-hypoxia or 3 h post-hypoxia. At 12 h after HI the mitochondrial status and ROS levels were determined. At 60th postnatal day the cognitive deficits were revealed in the Morris water maze reference and working spatial memories. Following behavioral analysis, histological assessment was performed and reactive astrogliosis was measured by GFAP expression. RESULTS: Results demonstrate that both pre- and post-HI administration of coumestrol were able to counteract the long-term cognitive and morphological impairments caused by HI, as well as to block the late reactive astrogliosis. The pre-HI administration of coumestrol was able to prevent the early mitochondrial dysfunction in the hippocampus of injured rat pups. CONCLUSION: Present data suggest that coumestrol exerts protection against experimental neonatal brain hypoxia-ischemia through, at least in part, early modulation of mitochondrial function.


Asunto(s)
Encéfalo/efectos de los fármacos , Cognición/efectos de los fármacos , Disfunción Cognitiva/tratamiento farmacológico , Cumestrol/farmacología , Hipoxia-Isquemia Encefálica/tratamiento farmacológico , Mitocondrias/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Animales , Encéfalo/metabolismo , Disfunción Cognitiva/metabolismo , Cumestrol/uso terapéutico , Hipoxia-Isquemia Encefálica/metabolismo , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , Mitocondrias/metabolismo , Fármacos Neuroprotectores/uso terapéutico , Fitoestrógenos/farmacología , Fitoestrógenos/uso terapéutico , Ratas , Ratas Wistar , Especies Reactivas de Oxígeno/metabolismo
12.
Mol Cell Endocrinol ; 485: 81-87, 2019 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-30738951

RESUMEN

In this study we determined the effect of fed and fasting (48 h) states on the expression of stanniocalcin-1 (Stc1) and stanniocalcin-2 (Stc2) in rat brown adipose tissue (BAT), as well as the in vitro effects of human stanniocalcin 1 and 2 (hSTC-1 and hSTC-2) hormones on lipid and glucose metabolism. In addition, lactate, glycogen levels and hexokinase (HK) activity were determined. In fasting Stc2 expression increased markedly. The targets of action of hSTC-1 and hSTC-2 were glucose uptake and oxidation as well as glycogen storage, controlling the energetic metabolism in BAT. The reduction in glycogen concentration induced by hSTC-2 in fed state might have deleterious consequences in BAT, such as decreased thermogenic activity, FA esterification and other adipocyte functions. On the other hand, the increase of glucose uptake caused by hSTC-1 of fed rats could play a role as a plasma glucose-clearing hormone in the postprandial period.


Asunto(s)
Tejido Adiposo Pardo/metabolismo , Glucosa/metabolismo , Glicoproteínas/genética , Péptidos y Proteínas de Señalización Intercelular/genética , Animales , Ayuno , Glucógeno/metabolismo , Glicoproteínas/metabolismo , Hexoquinasa/metabolismo , Humanos , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Metabolismo de los Lípidos , Masculino , Periodo Posprandial , Ratas , Ratas Wistar , Termogénesis
13.
Metab Brain Dis ; 33(3): 813-821, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29363039

RESUMEN

Progesterone displays a strong potential for the treatment of neonatal hypoxic-ischemic encephalopathy since it has been shown to be beneficial in the treatment of the central nervous system injuries in adult animals. Here, we evaluated the effects of the administration of progesterone (10 mg/kg) in seven-days-old male Wistar rats submitted to neonatal hypoxia-ischemia (HI). Progesterone was administered immediately before ischemia and/or 6 and 24 h after the onset of hypoxia. The body weight of the animals, the volume of brain lesion and the expression of p-Akt and procaspase-3 in the hippocampus were evaluated. All animals submitted to HI showed a reduction in the body weight. However, this reduction was more remarkable in those animals which received progesterone before surgery. Administration of progesterone was unable to reduce the volume of brain damage caused by HI. Moreover, no significant differences were observed in the expression of p-Akt and procaspase-3 in animals submitted to HI and treated with either progesterone or vehicle. In summary, progesterone did not show a neuroprotective effect on the volume of brain lesion in neonatal rats submitted to hypoxia-ischemia. Furthermore, progesterone was unable to modulate p-Akt and procaspase-3 signaling pathways, which may explain the absence of neuroprotection. On the other hand, it seems that administration of progesterone before ischemia exerts some systemic effect, leading to a remarkable reduction in the body weight.


Asunto(s)
Lesiones Encefálicas/tratamiento farmacológico , Encéfalo/efectos de los fármacos , Hipoxia-Isquemia Encefálica/tratamiento farmacológico , Progesterona/farmacología , Animales , Animales Recién Nacidos , Peso Corporal/efectos de los fármacos , Encéfalo/metabolismo , Lesiones Encefálicas/metabolismo , Caspasa 3/metabolismo , Masculino , Fármacos Neuroprotectores/farmacología , Progesterona/metabolismo , Ratas Wistar
14.
Water Sci Technol ; 76(7-8): 2195-2202, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29068349

RESUMEN

In the present study, nine coagulants having potential to be used for sewage treatment were compared to assess their efficiency in removing total coliform bacteria, Escherichia coli and adenovirus. The coagulants tested were metallic and organic and their efficiency was compared when treating samples of raw and treated sewage (activated sludge). Before the efficiency tests of the coagulants, viral concentration methods were compared. Coagulation tests were carried out by using the jar-test system and the doses used ranged from 100 ppm to 1,000 ppm. Viral DNA was extracted and subjected to real-time polymerase chain reaction (qPCR) using primers for the gene of AdV hexon. Aluminum sulfate (1,000 ppm) presented the best results for raw sewage among metal coagulants whereas Acquapol® C118 and WW (1,000 ppm) had the most satisfactory results among organic coagulants, both reducing up to 7 logs for coliforms and 4 logs for virus. For the treated effluent, FeCl2 (1,000 ppm) presented best results for metal coagulants, whereas, from organic coagulants, the best removal rates were for Acquapol® 893/11 (1,000 ppm), both reducing up to 3 logs for coliforms and 4 logs for virus.


Asunto(s)
Enterobacteriaceae/aislamiento & purificación , Escherichia coli/aislamiento & purificación , Aguas del Alcantarillado/microbiología , Virus/aislamiento & purificación , Microbiología del Agua , Reacción en Cadena en Tiempo Real de la Polimerasa , Taninos , Instalaciones de Eliminación de Residuos
15.
Braz J Microbiol ; 46(3): 715-23, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26413052

RESUMEN

Adenoviruses are among the most promising viral markers of fecal contamination. They are frequently found in the water, sediment and soil of regions impacted by human activity. Studies of the bioaccumulation of enteric viruses in shrimp are scarce. The cities located in the northern coast of the lake systems in Southern Brazil have high urbanization and intensive farming rates, and poor sewage collection and treatment. One hundred (n = 100) Farfantepenaeus paulensis pink-shrimp specimens and 48 water samples were collected from coastal lagoons between June 2012 and May 2013. Water samples were concentrated and the shrimp, mashed. After DNA extraction, samples were analyzed by real time polymerase chain reaction (qPCR) in order to detect and quantify viral genomes. Thirty-five percent of shrimp samples were positive for contamination, predominantly by avian adenoviruses. A total of 91.7% of water samples contained adenoviruses DNA, with the human form being the most frequent. Our results provided evidence of significant bioaccumulation of adenoviruses in shrimp, showing the extent of the impact of fecal pollution on aquatic ecosystems.


Asunto(s)
Adenoviridae/clasificación , Adenoviridae/aislamiento & purificación , Heces/virología , Penaeidae/virología , Contaminación del Agua , Animales , Brasil , Ecosistema , Geografía , Reacción en Cadena en Tiempo Real de la Polimerasa , Aguas del Alcantarillado/virología
16.
Braz. j. microbiol ; 46(3): l7235-723, July-Sept. 2015. tab, ilus
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1469613

RESUMEN

Adenoviruses are among the most promising viral markers of fecal contamination. They are frequently found in the water, sediment and soil of regions impacted by human activity. Studies of the bioaccumulation of enteric viruses in shrimp are scarce. The cities located in the northern coast of the lake systems in Southern Brazil have high urbanization and intensive farming rates, and poor sewage collection and treatment. One hundred (n = 100) Farfantepenaeus paulensis pink-shrimp specimens and 48 water samples were collected from coastal lagoons between June 2012 and May 2013. Water samples were concentrated and the shrimp, mashed. After DNA extraction, samples were analyzed by real time polymerase chain reaction (qPCR) in order to detect and quantify viral genomes. Thirty-five percent of shrimp samples were positive for contamination, predominantly by avian adenoviruses. A total of 91.7% of water samples contained adenoviruses DNA, with the human form being the most frequent. Our results provided evidence of significant bioaccumulation of adenoviruses in shrimp, showing the extent of the impact of fecal pollution on aquatic ecosystems..


Asunto(s)
Animales , Adenoviridae/clasificación , Adenoviridae/aislamiento & purificación , Heces/virología , Penaeidae/virología , Contaminación del Agua , Brasil , Ecosistema , Aguas del Alcantarillado/virología , Geografía , Reacción en Cadena en Tiempo Real de la Polimerasa
17.
Braz. j. microbiol ; 46(3): 715-723, July-Sept. 2015. tab, ilus
Artículo en Inglés | LILACS | ID: lil-755819

RESUMEN

Adenoviruses are among the most promising viral markers of fecal contamination. They are frequently found in the water, sediment and soil of regions impacted by human activity. Studies of the bioaccumulation of enteric viruses in shrimp are scarce. The cities located in the northern coast of the lake systems in Southern Brazil have high urbanization and intensive farming rates, and poor sewage collection and treatment. One hundred (n = 100) Farfantepenaeus paulensis pink-shrimp specimens and 48 water samples were collected from coastal lagoons between June 2012 and May 2013. Water samples were concentrated and the shrimp, mashed. After DNA extraction, samples were analyzed by real time polymerase chain reaction (qPCR) in order to detect and quantify viral genomes. Thirty-five percent of shrimp samples were positive for contamination, predominantly by avian adenoviruses. A total of 91.7% of water samples contained adenoviruses DNA, with the human form being the most frequent. Our results provided evidence of significant bioaccumulation of adenoviruses in shrimp, showing the extent of the impact of fecal pollution on aquatic ecosystems.

.


Asunto(s)
Animales , Adenoviridae/clasificación , Adenoviridae/aislamiento & purificación , Heces/virología , Penaeidae/virología , Contaminación del Agua , Brasil , Ecosistema , Geografía , Reacción en Cadena en Tiempo Real de la Polimerasa , Aguas del Alcantarillado/virología
18.
Braz. j. microbiol ; 44(3): 953-957, July-Sept. 2013. tab
Artículo en Inglés | LILACS | ID: lil-699826

RESUMEN

Viral gastroenteritis and other waterborne diseases are a major concern for health in Brazil. A number of studies were conducted about the presence of viruses on water samples from Brazilian areas. However, the knowledge about the occurrence of viral contamination of drinking water sources in rural settings of the country is insufficient. On the present work, 15 samples from 5 dairy farms located at the municipality of Tenente Portela were collected and analysed for the presence of human adenoviruses (HAdV), as well as human enteroviruses (EV) and rotaviruses (RV). HAdV was present on 66.66% of the water samples, and have been found in all samples from artesian wells and springs, which are used as sources of drinking water for the individuals inhabiting those farms. EV and RV found only in one sample each. The detection rates of HAdV on the water from these dairy farms are alarming and point towards a situation of elevated environmental contamination by fecal microorganisms of human origin and poor basic sanitation conditions.


Asunto(s)
Animales , Humanos , Adenovirus Humanos/aislamiento & purificación , Enterovirus/aislamiento & purificación , Rotavirus/aislamiento & purificación , Microbiología del Agua , Animales Domésticos , Brasil , Prevalencia , Población Rural
19.
Braz J Microbiol ; 44(3): 953-7, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24516464

RESUMEN

Viral gastroenteritis and other waterborne diseases are a major concern for health in Brazil. A number of studies were conducted about the presence of viruses on water samples from Brazilian areas. However, the knowledge about the occurrence of viral contamination of drinking water sources in rural settings of the country is insufficient. On the present work, 15 samples from 5 dairy farms located at the municipality of Tenente Portela were collected and analysed for the presence of human adenoviruses (HAdV), as well as human enteroviruses (EV) and rotaviruses (RV). HAdV was present on 66.66% of the water samples, and have been found in all samples from artesian wells and springs, which are used as sources of drinking water for the individuals inhabiting those farms. EV and RV found only in one sample each. The detection rates of HAdV on the water from these dairy farms are alarming and point towards a situation of elevated environmental contamination by fecal microorganisms of human origin and poor basic sanitation conditions.


Asunto(s)
Adenovirus Humanos/aislamiento & purificación , Enterovirus/aislamiento & purificación , Rotavirus/aislamiento & purificación , Microbiología del Agua , Animales , Animales Domésticos , Brasil , Humanos , Prevalencia , Población Rural
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