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1.
Cell Mol Neurobiol ; 42(1): 59-83, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33231827

RESUMO

In recent decades, a number of novel non-visual opsin photopigments belonging to the family of G protein- coupled receptors, likely involved in a number of non-image-forming processes, have been identified and characterized in cells of the inner retina of vertebrates. It is now known that the vertebrate retina is composed of visual photoreceptor cones and rods responsible for diurnal/color and nocturnal/black and white vision, and cells like the intrinsically photosensitive retinal ganglion cells (ipRGCs) and photosensitive horizontal cells in the inner retina, both detecting blue light and expressing the photopigment melanopsin (Opn4). Remarkably, these non-visual photopigments can continue to operate even in the absence of vision under retinal degeneration. Moreover, inner retinal neurons and Müller glial cells have been shown to express other photopigments such as the photoisomerase retinal G protein-coupled receptor (RGR), encephalopsin (Opn3), and neuropsin (Opn5), all able to detect blue/violet light and implicated in chromophore recycling, retinal clock synchronization, neuron-to-glia communication, and other activities. The discovery of these new photopigments in the inner retina of vertebrates is strong evidence of novel light-regulated activities. This review focuses on the features, localization, photocascade, and putative functions of these novel non-visual opsins in an attempt to shed light on their role in the inner retina of vertebrates and in the physiology of the whole organism.


Assuntos
Opsinas , Retina , Animais , Opsinas/fisiologia , Células Ganglionares da Retina , Células Fotorreceptoras Retinianas Bastonetes , Vertebrados
2.
Paediatr Anaesth ; 32(5): 617-624, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35156263

RESUMO

BACKGROUND: Pediatric spinal anesthesia is an old technique whose use is not widespread, in spite of reducing the risk of cardiorespiratory events (hypoxemia, bradycardia, and hypotension) associated with general anesthesia, especially in neonates and infants. This retrospective cohort study aimed to assess the safety and effectiveness of the pediatric spinal anesthesia program at our tertiary care hospital over 11 years. METHODS: Two hundred children, between 8 days and 13 years of age, who underwent lower body surgery under spinal anesthesia from May 2010 to July 2021 were included. Demographic and procedural data were collected, and success, failure, and complication rates calculated. RESULTS: The success rate was 97.5% (n = 195). The incidence of complications was 2% (n = 4). They were 2 cases of intraoperative hypoxemia and 2 cases of postoperative postdural puncture headache , and they quickly resolved with no sequelae. CONCLUSION: Pediatric spinal anesthesia is a safe and effective technique with good acceptance among anesthesiologists. Thus, the implementation of a pediatric spinal anesthesia program at a tertiary care hospital is feasible and affordable.


Assuntos
Raquianestesia , Cefaleia Pós-Punção Dural , Raquianestesia/efeitos adversos , Criança , Humanos , Hipóxia , Lactente , Recém-Nascido , Estudos Retrospectivos , Centros de Atenção Terciária
3.
Vet Pathol ; 56(5): 681-690, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31106677

RESUMO

Salmonella is a major foodborne pathogen and pork is one of the main sources of human salmonellosis. Understanding the pathogenesis and progression of the infection within the host is of interest to establish potential approaches to control the disease in pigs. The present study evaluates factors such as intestinal colonization, fecal shedding, and pathogen persistence by 2 studies using experimental challenge with Salmonella Typhimurium in weaned pigs and euthanasia at different time points (1, 2, and 6 and 2, 14, and 30 days postinfection [dpi], respectively). Histopathology of intestine at early time points (1 dpi and 2 dpi) showed severe damage to the epithelium together with an increase in polymorphonuclear cells and macrophages (P < .001), particularly in jejunum and ileum. Large quantities of Salmonella were detected within the contents of the ileum, cecum, and colon in early infection. Salmonella could also be observed in the medulla of tonsils and mesenteric lymph nodes. From 6 dpi onward, signs of recovery were observed, with progressive restoration of the epithelium, reduction of the inflammatory infiltrate, and elimination of Salmonella from the mucosa. Concentration of Salmonella in feces and ileum content decreased, but shedding did not cease even at 4 weeks after infection. Persistence of the bacteria in mesenteric lymph nodes was identified within the connective tissue at 14 and 30 dpi. Our results demonstrate a recovery of the disease after an initial acute phase but also show persistence within the lumen and surrounding lymphoid tissue. These findings are relevant to developing effective control strategies.


Assuntos
Gastroenteropatias/veterinária , Trato Gastrointestinal/microbiologia , Tecido Linfoide/microbiologia , Salmonelose Animal/microbiologia , Salmonella typhimurium/isolamento & purificação , Doenças dos Suínos/microbiologia , Animais , Fezes/microbiologia , Gastroenteropatias/microbiologia , Suínos
4.
Proc Natl Acad Sci U S A ; 113(46): 13215-13220, 2016 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-27789727

RESUMO

In the vertebrate retina, three types of photoreceptors-visual photoreceptor cones and rods and the intrinsically photosensitive retinal ganglion cells (ipRGCs)-converged through evolution to detect light and regulate image- and nonimage-forming activities such as photic entrainment of circadian rhythms, pupillary light reflexes, etc. ipRGCs express the nonvisual photopigment melanopsin (OPN4), encoded by two genes: the Xenopus (Opn4x) and mammalian (Opn4m) orthologs. In the chicken retina, both OPN4 proteins are found in ipRGCs, and Opn4x is also present in retinal horizontal cells (HCs), which connect with visual photoreceptors. Here we investigate the intrinsic photosensitivity and functioning of HCs from primary cultures of embryonic retinas at day 15 by using calcium fluorescent fluo4 imaging, pharmacological inhibitory treatments, and Opn4x knockdown. Results show that HCs are avian photoreceptors with a retinal-based OPN4X photopigment conferring intrinsic photosensitivity. Light responses in HCs appear to be driven through an ancient type of phototransduction cascade similar to that in rhabdomeric photoreceptors involving a G-protein q, the activation of phospholipase C, calcium mobilization, and the release of the inhibitory neurotransmitter GABA. Based on their intrinsic photosensitivity, HCs may have a key dual function in the retina of vertebrates, potentially regulating nonvisual tasks together with their sister cells, ipRGCs, and with visual photoreceptors, modulating lateral interactions and retinal processing.


Assuntos
Células Fotorreceptoras de Vertebrados/fisiologia , Células Horizontais da Retina/fisiologia , Opsinas de Bastonetes/fisiologia , Animais , Cálcio/fisiologia , Células Cultivadas , Galinhas , Embrião não Mamífero , Luz , Retinaldeído/fisiologia , Opsinas de Bastonetes/genética , Ácido gama-Aminobutírico/fisiologia
5.
Front Physiol ; 13: 840623, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35283802

RESUMO

The use of medical ozone in the treatment of chronic pain is progressively expanding in Spain and today it is used both in public and private medical centers. However, there is a great lack of knowledge about this technology not only in primary care but also in medical specialties. Although its biochemical bases are well determined and there are various systematic reviews and meta-analyses in the literature that justify its use in pain medicine, some professionals still are prejudiced against it. The evidence level of using medical ozone according SIGN (Scotish Intercollegiate Guideline Network) criteria is similar or superior to most of the techniques used in a Pain Unit. In this paper, we have done a review on ozone therapy in pain medicine, compiling the evidence published about it.

6.
Front Neurosci ; 15: 593562, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33867910

RESUMO

The scientific and educational community is becoming increasingly aware of the impact of current academic working conditions on graduate students' mental health and how this is affecting scientific progress and ultimately society as a whole. Our study aimed to shed light on the work-related mental health issues affecting graduate students, providing a comprehensive research work including psychological and biological assessment. Our findings showed that a sizeable number of graduate student present anxiety, depression, or high burnout and that the time spent in academia plays an important role. The graduate student population displayed a specific work-related mental health issues profile with an altered hypothalamic-pituitary-adrenal (HPA) axis and low levels of work engagement. Finally, graduate students were equally stressed, with less work engagement, and more anxious and depressed than general workers.

7.
Saudi J Anaesth ; 15(4): 450-453, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34658737

RESUMO

Despite the advances in pediatric anesthesia, infants have higher mortality and critical incidents rates than children, especially ex-prematures and those with comorbidity. We present the case of a high-risk infant who underwent elective laparoscopic gastrostomy under opioid-free anesthesia (OFA) combined with transversus abdominis plane (TAP) block with Dexmedetomidine (DEX). Perioperative opioids were entirely avoided, and intraoperative anesthetics and postoperative analgesic were considerably reduced. The infant showed cardiorespiratory stability and optimal analgesia during the uneventful procedure and the postoperative period. We consider OFA and TAP block with DEX a safe and effective anesthetic combination for high-risk infants.

8.
Pain Physician ; 24(1): E75-E85, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33400440

RESUMO

BACKGROUND: The central analgesic tapentadol prolonged release (PR) has proven effective and generally well tolerated in a broad range of chronic pain conditions. Long-term data of its use are still scarce. OBJECTIVES: To evaluate long-term effectiveness, tolerability, and safety of tapentadol PR in patients with severe chronic osteoarthritis (OA) knee pain or low back pain (LBP) who responded to tapentadol in 1 of 4 preceding 12-week phase 3b clinical trials. STUDY DESIGN: Open-label, uncontrolled, observational extension study of up to 72 weeks. SETTING: Fourteen centers in Spain. Protocol approval by the reference ethics committee for all the participating centers. METHODS: Eligible patients started the extension trial on the tapentadol PR dosage optimized for them in the preceding trial; dose adjustments were permitted throughout the extension. Treatment effectiveness outcomes included changes in pain intensity, sleep, state of health, quality of life, patient and clinician global impression of change, and patients' satisfaction with treatment. Patients with OA knee pain also answered the Western Ontario and McMaster Universities OA index, and patients with LBP with a possible neuropathic pain component completed neuropathic pain-related questionnaires. RESULTS: Eighty-three patients were enrolled: 40 with OA knee pain, 43 with LBP. The full analysis set consisted of 81 patients. Mean pain intensity remained relatively stable over the 72-week extension period with mean increases from baseline of 0.44 (95% confidence interval [CI], -0.1,1.0; Numeric Rating Scale) for all patients, 0.2 (95% CI, -0.5, 0.9) for patients with OA, and 0.68 (95% CI, -0.2, 1.6) for patients with LBP. State of health and quality of life baseline ratings were maintained; overall impression of change was "improved." Most patients (88.9%) reported at least good treatment satisfaction at the end of treatment. Mean daily tapentadol PR doses slightly increased from 313.3 ± 139.5 mg at baseline to 315.7 ± 140.1 mg at end of study. Uptitration was required for 8.4% of the patients, 4.8% had a dose reduction during the trial. Adverse events considered probably/likely or certainly related to tapentadol PR treatment by the investigator were documented for 18.1% of all patients, most commonly constipation (7.2%). Seven patients (8.4%) experienced adverse events leading to premature discontinuation. LIMITATIONS: An open-label design, stable concomitant analgesics (World Health Organization step I), and dose adjustments were allowed during the study. All patients had benefitted from tapentadol PR in preceding trials. CONCLUSIONS: Sustained pain relief and quality of life for up to 72 treatment weeks under relatively stable dosing, as well as the good safety profile, indicate the usefulness of tapentadol PR for patients who suffer from severe chronic OA knee pain and LBP with limited risk for tolerance development.


Assuntos
Analgésicos/uso terapêutico , Dor Lombar/tratamento farmacológico , Osteoartrite do Joelho/tratamento farmacológico , Manejo da Dor/métodos , Tapentadol/uso terapêutico , Idoso , Dor Crônica/tratamento farmacológico , Preparações de Ação Retardada/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Espanha , Resultado do Tratamento
10.
Pediatr Qual Saf ; 5(1): e254, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32190799

RESUMO

Risk management in healthcare institutions begins by first identifying the potential risks within a certain organization or specific area and then goes on to develop further strategies to reduce harm. The most common tool for this type of analysis is Strengths-Weaknesses-Opportunities-Threats (SWOT). METHODS: We conducted a SWOT analysis in our pediatric anesthesia program: key factors were identified in a matrix, prioritized in a score table, represented in a graph, and finally analyzed. RESULTS: Items obtained partial scores from 20 to 120. The item "lack of clinical protocols" was given greater weight (60) and received a lower value (1), resulting in the highest partial score (60) among the negative key factors and indicating a need for greater efforts to improve this specific aspect. CONCLUSION: The SWOT tool proved effective in identifying safety and quality key factors, and it provided information for initiating an improvement program.

11.
Mol Biol Rep ; 36(7): 1957-65, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18985438

RESUMO

This work describes the cloning and structural analysis of a Tpt1 cDNA coding for the porcine translationally controlled tumor protein (TCTP) molecule and its expression in porcine cells and tissues. Pig Tpt1 cDNA is 842-pb long that displays typical features of translationally controlled mRNAs, including a 5'-UTR containing a 5'-terminal oligopyrimidine tract (5'-TOP), and a 3'-UTR with a high CG-content and one AU rich element (ARE). Both 5'-UTR and 3'-UTR are highly conserved when they are compared with those of other mammals. The pig Tpt1 cDNA contains a 516-b open reading frame that encodes a predicted TCTP protein composed of 172 amino acids that exhibits extensive conservation compared with TCTP sequences from other species and a common structural feature with all the other TCTP proteins analyzed in mammals. Expression analysis demonstrated that Tpt1 mRNA is ubiquitously expressed in normal porcine tissues and cells, showing a higher expression in spleen, lymph nodes and lung, and a lower one in skin and heart. The pig Tpt1 gene localizes on the porcine chromosome 11, region p11.


Assuntos
Biomarcadores Tumorais/genética , Cromossomos de Mamíferos/metabolismo , Sus scrofa/genética , Regiões 3' não Traduzidas/genética , Regiões 5' não Traduzidas/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Biomarcadores Tumorais/química , Biomarcadores Tumorais/metabolismo , Clonagem Molecular , DNA Complementar/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Dados de Sequência Molecular , Filogenia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Alinhamento de Sequência , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico , Proteína Tumoral 1 Controlada por Tradução
12.
Front Neurosci ; 13: 1226, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31780892

RESUMO

According to the World Health Organization, an unhealthy diet and insufficient physical activity are the leading global risks to health. Dietary behavior is a modifiable factor in cardiovascular disease (CVD) prevention. Furthermore, the fact that cardiovascular events and stress-related emotional disorders share a common epidemiology may indicate the existence of pathways linking these two diseases (Chauvet-Gelinier and Bonin, 2017). Psychosocial stress can lead to changes in dietary patterns (DP) and under chronic stress conditions, high caloric and hyperpalatable foods are preferred. The interplay between these two factors impacts on several biological pathways: for example, it can prime the hippocampus to produce a potentiated neuroinflammatory response, generating memory deficits; it can also affect gut microbiota composition, ultimately influencing behavior and brain health and creating a predisposition to the development of diseases such as obesity, CVD, diabetes and metabolic syndrome. Though both cognition and emotion can be heavily affected by caloric intake, diet composition and stress, the molecular pathways involved remain elusive (Spencer et al., 2017). In this review, we describe the interplay between stress and DP at a molecular level, and how these factors relate to brain health and mental fitness. Finally, we show how these findings could give rise to novel therapeutic targets for chronic diseases.

13.
Res Vet Sci ; 124: 310-316, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31030118

RESUMO

NOD-like receptors (NLRs) play a key role in the innate immune system, acting as a second line of surveillance against pathogens. NLRs detect particular bacteria that have gained access to the cytoplasm, evading recognition by other pattern recognition receptors, such as Toll-like receptors. It has been demonstrated that coding sequence-single nucleotide polymorphisms may alter the ligand recognition ability of NLRs, affecting their pathogen-sensing function. However, there have been no data relating to the identification and functional analysis of SNPs in porcine NLR promoters. We examined the promoter sequences of the porcine NOD1 and NOD2 genes with the aim to identify and to evaluate the effect of genetic variations on promoter activity. Six SNPs in NOD1 and three SNPs in NOD2 were identified. Luciferase reporter gene assays showed significant differences in promoter activity between allele variants of NOD1 -920G>A (NC_010460.4:g.42431413G>A) and NOD2 -1670G>A (NC_010448.4:g.34169122T>C) SNPs. The results suggest that promoter polymorphisms could modify the expression levels of porcine NOD1 and NOD2 genes.


Assuntos
Proteína Adaptadora de Sinalização NOD1/genética , Proteína Adaptadora de Sinalização NOD2/genética , Polimorfismo de Nucleotídeo Único/genética , Regiões Promotoras Genéticas/genética , Sus scrofa/genética , Animais , Proteína Adaptadora de Sinalização NOD1/metabolismo , Proteína Adaptadora de Sinalização NOD2/metabolismo , Análise de Sequência de DNA , Sus scrofa/metabolismo
14.
Gene ; 408(1-2): 9-17, 2008 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-18006249

RESUMO

Integrins are heterodimeric cell adhesion molecules with major roles in a variety of biological processes ranging from cell migration to tissue organization, immune and non-immune defense mechanisms and oncogenic transformation. Members of the beta(3) integrin subfamily are composed of a beta(3) subunit (CD61) non-covalently associated with two alpha subunits, alpha(IIb) (CD41) and alpha(v) (CD51), to constitute a group of transmembrane glycoproteins that participate in many physiologically important events. This investigation has focused on the molecular characterization of the cDNA encoding the porcine beta(3) integrin subunit. The deduced 762-amino acid sequence was 93, 92, 91, 89, 79 and 73% homologous to human, dog, rabbit, mouse, chicken and Xenopus laevis CD61 protein, respectively. Porcine CD61 molecule shares many structural features with human CD61, including a region containing a metal ion-dependent adhesion site (MIDAS) folding into an I domain-like structure. Through PCR-SSCP analysis and sequencing, six polymorphic positions were detected in the cDNA sequence of porcine CD61, and their frequencies were observed from a collection of 47 pigs. Expression analysis was done at two different levels: expression of the CD61 mRNA by RT-PCR and localization of the protein by immunohistochemistry. Our results show that CD61 transcripts were detected mainly in platelets and hematopoietic tissues. The immunohistochemical tissue localization of CD61 protein by a specific monoclonal antibody against CD61 recombinant protein showed that CD61 was expressed on vascular and non-vascular smooth muscle, epithelium and myeloid cells, being undetectable in cells of the lymphoid lineage. Furthermore, pulmonary intravascular macrophages (PIM), a subpopulation of macrophages which seem to play an important role in blood clearance, expressed much more CD61 when compared to pulmonary alveolar macrophages (PAM). The knowledge of the structure and distribution of the CD61 provides insight into the physiological function of the porcine beta(3) integrins and should be of importance in understanding the role of this integrin family in biological processes.


Assuntos
Integrina beta3/genética , Suínos/genética , Sequência de Aminoácidos , Animais , Células Cultivadas , Clonagem Molecular , Imuno-Histoquímica , Integrina beta3/química , Integrina beta3/metabolismo , Dados de Sequência Molecular , Polimorfismo de Nucleotídeo Único , Subunidades Proteicas/química , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo , RNA Mensageiro/metabolismo , Alinhamento de Sequência , Suínos/metabolismo
15.
A A Pract ; 11(11): 293-295, 2018 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-29851688

RESUMO

Spinal anesthesia is practical and safe in infants and toddlers and prevents perioperative complications including cardiorespiratory instability and apnea. Other perioperative advantages include reduced time from surgery completion to operating room exit and first feed. This article presents the case of an ex-premature infant who underwent laparoscopic inguinal hernia repair under spinal anesthesia. The infant remained calm and stable throughout the uneventful procedure and postoperative period. Spinal anesthesia may be feasible for laparoscopic herniotomy when pneumoperitoneum pressure and operative time are restricted to 8 mm Hg and 60 minutes, respectively, with sensory level at T10 or higher.


Assuntos
Raquianestesia/métodos , Hérnia Inguinal/cirurgia , Herniorrafia/métodos , Feminino , Humanos , Lactente , Laparoscopia , Duração da Cirurgia , Resultado do Tratamento
16.
Sci Rep ; 8(1): 7788, 2018 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-29773876

RESUMO

Salmonella is a major foodborne pathogen which successfully infects animal species for human consumption such as swine. The pathogen has a battery of virulence factors which it uses to colonise and persist within the host. The host microbiota may play a role in resistance to, and may also be indirectly responsible from some of the consequences of, Salmonella infection. To investigate this, we used 16S rRNA metagenomic sequencing to determine the changes in the gut microbiota of pigs in response to infection by Salmonella Typhimurium at three locations: ileum mucosa, ileum content and faeces. Early infection (2 days post-infection) impacted on the microbiome diversity at the mucosa, reflected in a decrease in representatives of the generally regarded as desirable genera (i.e., Bifidobacterium and Lactobacillus). Severe damage in the epithelium of the ileum mucosa correlated with an increase in synergistic (with respect to Salmonella infection; Akkermansia) or opportunistically pathogenic bacteria (Citrobacter) and a depletion in anaerobic bacteria (Clostridium spp., Ruminococcus, or Dialliser). Predictive functional analysis, together with metabolomic analysis revealed changes in glucose and lipid metabolism in infected pigs. The observed changes in commensal healthy microbiota, including the growth of synergistic or potentially pathogenic bacteria and depletion of beneficial or competing bacteria, could contribute to the pathogen's ability to colonize the gut successfully. The findings from this study could be used to form the basis for further research aimed at creating intervention strategies to mitigate the effects of Salmonella infection.


Assuntos
Microbiota , Infecções por Salmonella/microbiologia , Salmonella typhimurium/patogenicidade , Suínos/microbiologia , Animais , Fezes/microbiologia , Íleo/microbiologia , Mucosa Intestinal/microbiologia
17.
Dev Comp Immunol ; 31(7): 738-47, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17169425

RESUMO

CD14 is a membrane-associated glycosylphosphatidylinositol (GPI)-anchored protein that binds lipopolysaccharide (LPS) of Gram-negative bacteria and enables LPS-dependent responses in a variety of cells. In this study a cDNA containing the porcine CD14 coding sequence has been cloned and its complete sequence determined. The amino acid sequence deduced from pig CD14 cDNA encodes a 373 amino acid polypeptide that exhibits 75%, 72%, 69%, 66%, 57% and 56% similarity to CD14 from cow, horse, human, rabbit, mouse and rat, respectively. Structural analysis showed that the porcine CD14 is a membrane glycoprotein with a GPI-anchor site and an extracellular domain containing 11 leucine-rich repeats. In addition, the LPS-binding regions identified in the human CD14 are highly conserved in the N-terminal domain of the porcine sequence. Fluorescence in situ hybridization was used to locate the CD14 gene on the pig chromosome 2, band q28. Expression analysis revealed that porcine CD14 transcripts were detected in all tissues and cells examined, suggesting that the expression of porcine CD14 gene is not restricted to myeloid cell lineage. Finally, we report that LPS stimulation significantly up-regulated CD14 gene expression in porcine alveolar macrophages.


Assuntos
Receptores de Lipopolissacarídeos/genética , Suínos/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Mapeamento Cromossômico , Clonagem Molecular , DNA Complementar/genética , Hibridização in Situ Fluorescente , Receptores de Lipopolissacarídeos/biossíntese , Receptores de Lipopolissacarídeos/imunologia , Lipopolissacarídeos/imunologia , Macrófagos Alveolares/imunologia , Dados de Sequência Molecular , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Alinhamento de Sequência , Análise de Sequência de DNA , Suínos/imunologia
19.
Mol Neurobiol ; 54(4): 2507-2517, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-26984602

RESUMO

The vertebrate retina contains typical photoreceptor (PR) cones and rods responsible for day/night vision, respectively, and intrinsically photosensitive retinal ganglion cells (ipRGCs) involved in the regulation of non-image-forming tasks. Rhodopsin/cone opsin photopigments in visual PRs or melanopsin (Opn4) in ipRGCs utilizes retinaldehyde as a chromophore. The retinoid regeneration process denominated as "visual cycle" involves the retinal pigment epithelium (RPE) or Müller glial cells. Opn4, on the contrary, has been characterized as a bi/tristable photopigment, in which a photon of one wavelength isomerizes 11-cis to all-trans retinal (Ral), with a second photon re-isomerizing it back. However, it is unknown how the chromophore is further metabolized in the inner retina. Nor is it yet clear whether an alternative secondary cycle occurs involving players such as the retinal G-protein-coupled receptor (RGR), a putative photoisomerase of unidentified inner retinal activity. Here, we investigated the role of RGR in retinoid photoisomerization in Opn4x (Xenopus ortholog) (+) RGC primary cultures free of RPE and other cells from chicken embryonic retinas. Opn4x (+) RGCs display significant photic responses by calcium fluorescent imaging and photoisomerize exogenous all-trans to 11-cis Ral and other retinoids. RGR was found to be expressed in developing retina and in primary cultures; when its expression was knocked down, the levels of 11-cis, all-trans Ral, and all-trans retinol in cultures exposed to light were significantly higher and those in all-trans retinyl esters lower than in dark controls. The results support a novel role for RGR in ipRGCs to modulate retinaldehyde levels in light, keeping the balance of inner retinal retinoid pools.


Assuntos
Proteínas do Olho/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Retina/metabolismo , Vias Visuais/metabolismo , Animais , Cálcio/metabolismo , Células Cultivadas , Embrião de Galinha , Galinhas , Isomerismo , Modelos Biológicos , Células Ganglionares da Retina/metabolismo , Retinaldeído/metabolismo , Retinoides/metabolismo
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