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1.
Cureus ; 16(5): e59541, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38826911

RESUMO

Idelalisib, a phosphoinositide 3-kinase delta (PI3Kδ) inhibitor, effectively treats relapsed chronic lymphocytic leukemia (CLL). While this targeted approach offers a therapeutic edge, particularly in B-cell malignancies, it is associated with complications such as pneumonitis. This report details idelalisib-induced pneumonitis, highlighting the importance of early diagnosis and tailored treatment in achieving a favorable patient outcome.

2.
Eur J Neurosci ; 59(9): 2240-2255, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38258622

RESUMO

Spatial memory encoding depends in part on cholinergic modulation. How acetylcholine supports spatial memory encoding is not well understood. Prior studies indicate that acetylcholine release is correlated with exploration, including epochs of rearing onto hind legs. Here, to test whether elevated cholinergic tone increases the probability of rearing, we tracked rearing frequency and duration while optogenetically modulating the activity of choline acetyltransferase containing (i.e., acetylcholine producing) neurons of the medial septum in rats performing a spatial working memory task (n = 17 rats). The cholinergic neurons were optogenetically inhibited using halorhodopsin for the duration that rats occupied two of the four open arms during the study phase of an 8-arm radial arm maze win-shift task. Comparing rats' behaviour in the two arm types showed that rearing frequency was not changed, but the average duration of rearing epochs became significantly longer. This effect on rearing was observed during optogenetic inhibition but not during sham inhibition or in rats that received infusions of a fluorescent reporter virus (i.e., without halorhodopsin; n = 6 rats). Optogenetic inhibition of cholinergic neurons during the pretrial waiting phase had no significant effect on rearing, indicating a context-specificity of the observed effects. These results are significant in that they indicate that cholinergic neuron activity in the medial septum is correlated with rearing not because it motivates an exploratory state but because it contributes to the processing of information acquired while rearing.


Assuntos
Neurônios Colinérgicos , Optogenética , Memória Espacial , Animais , Neurônios Colinérgicos/fisiologia , Neurônios Colinérgicos/efeitos dos fármacos , Neurônios Colinérgicos/metabolismo , Memória Espacial/fisiologia , Memória Espacial/efeitos dos fármacos , Masculino , Ratos , Optogenética/métodos , Ratos Long-Evans , Colina O-Acetiltransferase/metabolismo , Colina O-Acetiltransferase/genética , Acetilcolina/metabolismo , Memória de Curto Prazo/fisiologia , Memória de Curto Prazo/efeitos dos fármacos , Aprendizagem em Labirinto/fisiologia , Aprendizagem em Labirinto/efeitos dos fármacos
4.
bioRxiv ; 2023 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-37873370

RESUMO

Spatial memory encoding depends in part on cholinergic modulation. How acetylcholine supports spatial memory encoding is not well understood. Prior studies indicate that acetylcholine release is correlated with exploration, including epochs of rearing onto hind legs. Here, to test whether elevated cholinergic tone increases the probability of rearing, we tracked rearing frequency and duration while optogenetically modulating the activity of choline acetyltransferase containing (i.e., acetylcholine producing) neurons of the medial septum in rats performing a spatial working memory task (n = 17 rats). The cholinergic neurons were optogenetically inhibited using halorhodopsin for the duration that rats occupied two of the four open arms during the study phase of an 8-arm radial arm maze win-shift task. Comparing rats' behavior in the two arm types showed that rearing frequency was not changed but the average duration of rearing epochs became significantly longer. This effect on rearing was observed during optogenetic inhibition but not during sham inhibition or in rats that received infusions of a fluorescent reporter virus (i.e., without halorhodopsin; n = 6 rats). Optogenetic inhibition of cholinergic neurons during the pre-trial waiting phase had no significant effect on rearing, indicating a context-specificity of the observed effects. These results are significant in that they indicate that cholinergic neuron activity in the medial septum is correlated with rearing not because it motivates an exploratory state but because it contributes to the processing of information acquired while rearing.

5.
Biomark Res ; 11(1): 90, 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37817261

RESUMO

BACKGROUND: Recent advances in circulating cell-free DNA (cfDNA) analysis from biofluids have opened new avenues for liquid biopsy (LB). However, current cfDNA LB assays are limited by the availability of existing information on established genotypes associated with tumor tissues. Certain cancers present with a limited list of established mutated cfDNA biomarkers, and thus, nonmutated cfDNA characteristics along with alternative biofluids are needed to broaden the available cfDNA targets for cancer detection. Saliva is an intriguing and accessible biofluid that has yet to be fully explored for its clinical utility for cancer detection. METHODS: In this report, we employed a low-coverage single stranded (ss) library NGS pipeline "Broad-Range cell-free DNA-Seq" (BRcfDNA-Seq) using saliva to comprehensively investigate the characteristics of salivary cfDNA (ScfDNA). The identification of cfDNA features has been made possible by applying novel cfDNA processing techniques that permit the incorporation of ultrashort, ss, and jagged DNA fragments. As a proof of concept using 10 gastric cancer (GC) and 10 noncancer samples, we examined whether ScfDNA characteristics, including fragmentomics, end motif profiles, microbial contribution, and human chromosomal mapping, could differentiate between these two groups. RESULTS: Individual and integrative analysis of these ScfDNA features demonstrated significant differences between the two cohorts, suggesting that disease state may affect the ScfDNA population by altering nuclear cleavage or the profile of contributory organism cfDNA to total ScfDNA. We report that principal component analysis integration of several aspects of salivary cell-free DNA fragmentomic profiles, genomic element profiles, end-motif sequence patterns, and distinct oral microbiome populations can differentiate the two populations with a p value of < 0.0001 (PC1). CONCLUSION: These novel features of ScfDNA characteristics could be clinically useful for improving saliva-based LB detection and the eventual monitoring of local or systemic diseases.

6.
Res Sq ; 2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37503289

RESUMO

Background: Recent advances in circulating cell-free DNA (cfDNA) analysis from biofluids have opened new avenues for liquid biopsy (LB). However, current cfDNA LB assays are limited by the availability of existing information on established genotypes associated with tumor tissues. Certain cancers present with a limited list of established mutated cfDNA biomarkers, and thus, nonmutated cfDNA characteristics along with alternative biofluids are needed to broaden the available cfDNA targets for cancer detection. Saliva is an intriguing and accessible biofluid that has yet to be fully explored for its clinical utility for cancer detection. Methods: In this report, we employed a low-coverage single stranded (ss) library NGS pipeline "Broad-Range cell-free DNA-Seq" (BRcfDNA-Seq) using saliva to comprehensively investigate the characteristics of salivary cfDNA (ScfDNA). The identification of cfDNA features has been made possible by applying novel cfDNA processing techniques that permit the incorporation of ultrashort, ss, and jagged DNA fragments. As a proof of concept using 10 gastric cancer (GC) and 10 noncancer samples, we examined whether ScfDNA characteristics, including fragmentomics, end motif profiles, microbial contribution, and human chromosomal mapping, could differentiate between these two groups. Results: Individual and integrative analysis of these ScfDNA features demonstrated significant differences between the two cohorts, suggesting that disease state may affect the ScfDNA population by altering nuclear cleavage or the profile of contributory organism cfDNA to total ScfDNA. We report that principal component analysis integration of several aspects of salivary cell-free DNA fragmentomic profiles, genomic element profiles, end-motif sequence patterns, and distinct oral microbiome populations can differentiate the two populations with a p value of < 0.0001 (PC1). Conclusion: These novel features of ScfDNA characteristics could be clinically useful for improving saliva-based LB detection and the eventual monitoring of local or systemic diseases.

7.
Sci Rep ; 12(1): 1789, 2022 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-35110572

RESUMO

Despite the recent precipitous decline in the cost of genome sequencing, library preparation for RNA-seq is still laborious and expensive for applications such as high throughput screening. Limited availability of RNA generated by some experimental workflows poses an additional challenge and increases the cost of RNA library preparation. In a search for low cost, automation-compatible RNA library preparation kits that maintain strand specificity and are amenable to low input RNA quantities, we systematically tested two recent commercial technologies-Swift RNA and Swift Rapid RNA, presently offered by Integrated DNA Technologies (IDT) -alongside the Illumina TruSeq stranded mRNA, the de facto standard workflow for bulk transcriptomics. We used the Universal Human Reference RNA (UHRR) (composed of equal quantities of total RNA from 10 human cancer cell lines) to benchmark gene expression in these kits, at input quantities ranging between 10 to 500 ng. We found normalized read counts between all treatment groups to be in high agreement. Compared to the Illumina TruSeq stranded mRNA kit, both Swift RNA library kits offer shorter workflow times enabled by their patented Adaptase technology. We also found the Swift RNA kit to produce the fewest number of differentially expressed genes and pathways directly attributable to input mRNA amount.


Assuntos
Biomarcadores Tumorais/genética , Biblioteca Gênica , Neoplasias/genética , RNA Neoplásico/análise , RNA-Seq/métodos , RNA-Seq/normas , Transcriptoma , Perfilação da Expressão Gênica , Humanos , Neoplasias/patologia , RNA Neoplásico/genética , Análise de Sequência de RNA/métodos , Células Tumorais Cultivadas
8.
Endocrinology ; 160(6): 1547-1560, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-31127273

RESUMO

Sirtuin 1 (Sirt1) is an NAD-dependent class III deacetylase that functions as a cellular energy sensor. In addition to its well-characterized effects in peripheral tissues, evidence suggests that SIRT1 in neurons plays a role in the central regulation of energy balance and reproduction, but no studies have addressed the contribution of astrocytes. We show here that overexpression of SIRT1 in astrocytes causes markedly increased food intake, body weight gain, and glucose intolerance, but expression of a deacetylase-deficient SIRT1 mutant decreases food intake and body weight and improves glucose tolerance, particularly in female mice. Paradoxically, the effect of these SIRT1 mutants on insulin tolerance was reversed, with overexpression showing greater insulin sensitivity. The mice overexpressing SIRT1 were more active, generated more heat, and had elevated oxygen consumption, possibly in compensation for the increased food intake. The female overexpressing mice were also more sensitive to diet-induced obesity. Reproductively, the mice expressing the deacetylase-deficient SIRT1 mutant had impaired estrous cycles, decreased LH surges, and fewer corpora lutea, indicating decreased ovulation. The GnRH neurons were responsive to kisspeptin stimulation, but hypothalamic expression of Kiss1 was reduced in the mutant mice. Our results showed that SIRT1 signaling in astrocytes can contribute to metabolic and reproductive regulation independent of SIRT1 effects in neurons.


Assuntos
Astrócitos/metabolismo , Ingestão de Alimentos/fisiologia , Ciclo Estral/metabolismo , Intolerância à Glucose/metabolismo , Glucose/metabolismo , Sirtuína 1/metabolismo , Aumento de Peso/fisiologia , Animais , Ciclo Estral/genética , Feminino , Hormônio Foliculoestimulante/sangue , Intolerância à Glucose/genética , Hormônio Liberador de Gonadotropina/metabolismo , Hipotálamo/metabolismo , Resistência à Insulina/fisiologia , Leptina/sangue , Hormônio Luteinizante/sangue , Masculino , Camundongos , Neurônios/metabolismo , Sirtuína 1/genética , Testículo/metabolismo
9.
J Endocr Soc ; 3(2): 427-445, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30746504

RESUMO

Sirt1 is an NAD-dependent, class III deacetylase that functions as a cellular energy sensor. In addition to its well-characterized effects in peripheral tissues, emerging evidence suggests that neuronal Sirt1 activity plays a role in the central regulation of energy balance and glucose metabolism. In this study, we generated mice expressing an enzymatically inactive form (N-MUT) or wild-type (WT) SIRT1 (N-OX) in mature neurons. N-OX male and female mice had impaired glucose tolerance, and N-MUT female, but not male, mice had improved glucose tolerance compared with that of WT littermates. Furthermore, glucose tolerance was improved in all mice with caloric restriction (CR) but was greater in the N-OX mice, who had better glucose tolerance than their littermates. At the reproductive level, N-OX females had impaired estrous cycles, with increased cycle length and more time in estrus. LH and progesterone surges were absent on the evening of proestrus in the N-OX mice, suggesting a defect in spontaneous ovulation, which was confirmed by the ovarian histology revealing fewer corpora lutea. Despite this defect, the mice were still fertile when mated to WT mice on the day of proestrus, indicating that the mice could respond to normal pheromonal or environmental cues. When subjected to CR, the N-OX mice went into diestrus arrest earlier than their littermates. Together, these results suggested that the overexpression of SIRT1 rendered the mice more sensitive to the metabolic improvements and suppression of reproductive cycles by CR, which was independent of circadian rhythms.

10.
Development ; 145(5)2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29437830

RESUMO

Human cleft lip with or without cleft palate (CL/P) is a common craniofacial abnormality caused by impaired fusion of the facial prominences. We have previously reported that, in the mouse embryo, epithelial apoptosis mediates fusion at the seam where the prominences coalesce. Here, we show that apoptosis alone is not sufficient to remove the epithelial layers. We observed morphological changes in the seam epithelia, intermingling of cells of epithelial descent into the mesenchyme and molecular signatures of epithelial-mesenchymal transition (EMT). Utilizing mouse lines with cephalic epithelium-specific Pbx loss exhibiting CL/P, we demonstrate that these cellular behaviors are Pbx dependent, as is the transcriptional regulation of the EMT driver Snail1. Furthermore, in the embryo, the majority of epithelial cells expressing high levels of Snail1 do not undergo apoptosis. Pbx1 loss- and gain-of-function in a tractable epithelial culture system revealed that Pbx1 is both necessary and sufficient for EMT induction. This study establishes that Pbx-dependent EMT programs mediate murine upper lip/primary palate morphogenesis and fusion via regulation of Snail1. Of note, the EMT signatures observed in the embryo are mirrored in the epithelial culture system.


Assuntos
Padronização Corporal/genética , Transição Epitelial-Mesenquimal/genética , Face/embriologia , Morfogênese/genética , Nariz/embriologia , Fator de Transcrição 1 de Leucemia de Células Pré-B/fisiologia , Fatores de Transcrição da Família Snail/genética , Animais , Apoptose/genética , Células Cultivadas , Fenda Labial/embriologia , Fenda Labial/genética , Fissura Palatina/embriologia , Fissura Palatina/genética , Embrião de Mamíferos , Face/anormalidades , Regulação da Expressão Gênica no Desenvolvimento , Lábio/embriologia , Camundongos , Camundongos Transgênicos , Palato/embriologia , Fator de Transcrição 1 de Leucemia de Células Pré-B/genética
11.
Nat Commun ; 8(1): 1970, 2017 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-29213092

RESUMO

Robustness to perturbation is a fundamental feature of complex organisms. Mutations are the raw material for evolution, yet robustness to their effects is required for species survival. The mechanisms that produce robustness are poorly understood. Nonlinearities are a ubiquitous feature of development that may link variation in development to phenotypic robustness. Here, we manipulate the gene dosage of a signaling molecule, Fgf8, a critical regulator of vertebrate development. We demonstrate that variation in Fgf8 expression has a nonlinear relationship to phenotypic variation, predicting levels of robustness among genotypes. Differences in robustness are not due to gene expression variance or dysregulation, but emerge from the nonlinearity of the genotype-phenotype curve. In this instance, embedded features of development explain robustness differences. How such features vary in natural populations and relate to genetic variation are key questions for unraveling the origin and evolvability of this feature of organismal development.


Assuntos
Evolução Molecular , Variação Genética , Modelos Genéticos , Fenótipo , Animais , Evolução Biológica , Simulação por Computador , Fator 8 de Crescimento de Fibroblasto/genética , Dosagem de Genes , Expressão Gênica , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Genótipo , Masculino , Camundongos , Mutação , Dinâmica não Linear , RNA/genética
12.
J Pharmacol Exp Ther ; 363(1): 104-113, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28778859

RESUMO

The increasing availability of prescription opioid analgesics for the treatment of pain has been paralleled by an epidemic of opioid misuse, diversion, and overdose. The development of abuse-deterrent formulations (ADFs) of conventional opioids such as oxycodone and morphine represents an advance in the field and has had a positive but insufficient impact, as most opioids are still prescribed in highly abusable, non-ADF forms, and abusers can tamper with ADF medications to liberate the abusable opioid within. The abuse liability of mu-opioid agonists appears to be dependent on their rapid rate of entry into the central nervous system (CNS), whereas analgesic activity appears to be a function of CNS exposure alone, suggesting that a new opioid agonist with an inherently low rate of influx across the blood-brain barrier could mediate analgesia with low abuse liability, regardless of formulation or route of administration. NKTR-181 is a novel, long-acting, selective mu-opioid agonist with structural properties that reduce its rate of entry across the blood-brain barrier compared with traditional mu-opioid agonists. NKTR-181 demonstrated maximum analgesic activity comparable to that of oxycodone in hot-plate latency and acetic-acid writhing models. NKTR-181 was distinguishable from oxycodone by its reduced abuse potential in self-administration and progressive-ratio break point models, with behavioral effects similar to those of saline, as well as reduced CNS side effects as measured by the modified Irwin test. The in vitro and in vivo studies presented here demonstrate that NKTR-181 is the first selective mu-opioid agonist to combine analgesic efficacy and reduced abuse liability through the alteration of brain-entry kinetics.


Assuntos
Analgésicos Opioides/farmacologia , Morfinanos/farmacologia , Transtornos Relacionados ao Uso de Substâncias/prevenção & controle , Analgésicos Opioides/química , Analgésicos Opioides/metabolismo , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/metabolismo , Células CACO-2 , Relação Dose-Resposta a Droga , Composição de Medicamentos , Humanos , Masculino , Morfinanos/química , Morfinanos/metabolismo , Permeabilidade , Ratos , Ratos Sprague-Dawley , Receptores Opioides mu/metabolismo , Fatores de Tempo
13.
Case Rep Ophthalmol Med ; 2017: 9821416, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28695031

RESUMO

This paper presents a case demonstrating repair of traumatic macular hole and submacular hemorrhage with intravitreal gas tamponade and t-PA in an office setting.

14.
Genesis ; 51(10): 677-89, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23897749

RESUMO

Mouse models provide valuable opportunities for probing the underlying pathology of human birth defects. By using an N-ethyl-N-nitrosourea-based screen for recessive mutations affecting craniofacial anatomy, we isolated a mouse strain, Dogface-like (DL), with abnormal skull and snout morphology. Examination of the skull indicated that these mice developed craniosynostosis of the lambdoid suture. Further analysis revealed skeletal defects related to the pathology of basal cell nevus syndrome (BCNS) including defects in development of the limbs, scapula, ribcage, secondary palate, cranial base, and cranial vault. In humans, BCNS is often associated with mutations in the Hedgehog receptor PTCH1 and genetic mapping in DL identified a point mutation at a splice donor site in Ptch1. By using genetic complementation analysis we determined that DL is a hypomorphic allele of Ptch1, leading to increased Hedgehog signaling. Two aberrant transcripts are generated by the mutated Ptch1(DL) gene, which would be predicted to reduce significantly the levels of functional Patched1 protein. This new Ptch1 allele broadens the mouse genetic reagents available to study the Hedgehog pathway and provides a valuable means to study the underlying skeletal abnormalities in BCNS. In addition, these results strengthen the connection between elevated Hedgehog signaling and craniosynostosis.


Assuntos
Síndrome do Nevo Basocelular/genética , Osso e Ossos/anormalidades , Craniossinostoses/genética , Modelos Animais de Doenças , Mutação Puntual , Receptores de Superfície Celular/genética , Animais , Síndrome do Nevo Basocelular/embriologia , Síndrome do Nevo Basocelular/patologia , Osso e Ossos/embriologia , Craniossinostoses/embriologia , Craniossinostoses/patologia , Embrião de Mamíferos , Proteínas Hedgehog/fisiologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Receptores Patched , Receptor Patched-1 , Transdução de Sinais/genética , Crânio/anormalidades , Crânio/embriologia
15.
Exp Dermatol ; 18(12): 1016-21, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19555433

RESUMO

Epidermal development and differentiation are tightly controlled processes that culminate in the formation of the epidermal barrier. A critical regulator of different stages of epidermal development and differentiation is the transcription factor p63. More specifically, we previously demonstrated elsewhere that p63 is required for both the commitment to stratification and the commitment to terminal differentiation. We now demonstrate that DeltaNp63alpha, the predominantly expressed p63 isoform in postnatal epidermis, also plays a role in the final stages of epidermal differentiation, namely the formation of the epidermal barrier. We found that DeltaNp63alpha contributes to epidermal barrier formation by directly inducing expression of ALOX12, a lipoxygenase which contributes to epidermal barrier function. Our data demonstrate that DeltaNp63alpha directly interacts with the promoter of Alox12 in the developing epidermis. Furthermore, we found that the induction of Alox12 expression by DeltaNp63alpha depends on intact p63 binding sites in the Alox12 promoter. Finally, we found that DeltaNp63alpha can induce Alox12 expression only in differentiating keratinocytes, consistent with the role of ALOX12 in epidermal barrier formation.


Assuntos
Araquidonato 12-Lipoxigenase/metabolismo , Epiderme/metabolismo , Fosfoproteínas/metabolismo , Transativadores/metabolismo , Animais , Araquidonato 12-Lipoxigenase/genética , Cálcio/farmacologia , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Células Cultivadas , Imunoprecipitação da Cromatina , DNA/metabolismo , Regulação para Baixo/genética , Indução Enzimática , Epiderme/embriologia , Epiderme/enzimologia , Genes Reporter/genética , Quinase I-kappa B/genética , Queratinócitos/citologia , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Luciferases/genética , Luciferases/metabolismo , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Mifepristona/farmacologia , Análise de Sequência com Séries de Oligonucleotídeos , Fosfoproteínas/genética , Mutação Puntual/genética , Regiões Promotoras Genéticas/genética , Ligação Proteica/genética , Elementos de Resposta/genética , Pele/efeitos dos fármacos , Pele/embriologia , Pele/metabolismo , Transativadores/genética , Transdução Genética
16.
Ann N Y Acad Sci ; 1144: 176-88, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19076376

RESUMO

Adult rats and mice born to dams exposed to alcohol (fetal alcohol-exposed [FAE]) exhibit enhanced activity of their hypothalamic-pituitary-adrenal (HPA) axis when exposed to stressors. However, the mechanisms responsible for this phenomenon remain incompletely understood. Here two possibilities are reviewed: one that pertains to nitric oxide (NO), an unstable gas that stimulates the HPA axis; and one that focuses on catecholamines, which also stimulate this axis. Significant alterations were not observed in levels of NO synthase, the enzyme responsible for NO formation, in the paraventricula nucleus (PVN) of FAE rats. However, the stimulatory influence of this gas on the hypothalamic-pituitary-adrenal (HPA) axis was enhanced in these animals, thereby providing a mechanism likely to participate in the neuroendocrine hyperactivity that is the hallmark of this model. It was also recently shown that, while the ability of catecholamines to release adrenocorticotropic hormone (ACTH) was comparable in control rats and rats exposed to alcohol during embryonic development, there was a significant upregulation of the C1 brain-stem region when these latter animals were exposed to mild footshocks. Since this region sends prominent projections to the PVN, its increased activity may participate in the HPA axis hyperactivity observed in FAE offspring. Finally, microarray technology was used to search for potential differences in genes present in the brains of control and FAE mice. When these brains were collected on day 17.5 of embryonic development, several genes were upregulated, while others were downregulated, which may provide potential new candidates that mediate the influence of prenatal alcohol on the HPA axis of adult offspring.


Assuntos
Etanol/farmacologia , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Neuropeptídeos/sangue , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Efeitos Tardios da Exposição Pré-Natal/sangue , Hormônio Adrenocorticotrópico/sangue , Animais , Hormônio Liberador da Corticotropina/sangue , Feminino , Transtornos do Espectro Alcoólico Fetal/metabolismo , Humanos , Sistema Hipotálamo-Hipofisário/fisiologia , Camundongos , Neurotransmissores/metabolismo , Sistema Hipófise-Suprarrenal/fisiologia , Gravidez , Ratos , Vasopressinas/sangue
17.
Avian Dis ; 52(3): 487-90, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18939640

RESUMO

Tetracycline (tet) resistance in Campylobacter isolated from organically raised broilers was investigated in this study. Two hundred forty-five samples from an organic broiler farm were collected weekly from the first week to the end of the production cycle, and they were cultured for thermophilic Campylobacter. Tetracycline resistance of these Campylobacter isolates was identified by the agar dilution method, whereas DNA fingerprinting profiles of tet-susceptible and tet-resistant strains were determined by pulsed-field gel electrophoresis (PFGE). None of the Campylobacter isolates from the third and the fourth week of the production period were resistant to tetracycline, whereas 66.7% of the isolates from the fifth week were resistant to this antibiotic. Although the prevalence of tetracycline resistance reached 100.0% during the sixth and seventh week, less than 34.0% of the isolates from the 10th week were resistant to this antimicrobial agent. In addition, only 13.8% of Campylobacter isolates from the intestinal tracts of these organically raised broilers were resistant to tetracycline. The presence of the tet(O) gene was detected in 98.9% of tet-resistant Campylobacter isolates, and tet-susceptible and tet-resistant Campylobacter strains showed distinct PFGE genotypes. The results suggest that the Campylobacter strains isolated from the early stage of the production were susceptible to tetracycline, but they were subsequently displaced by tet-resistant Campylobacter.


Assuntos
Infecções por Campylobacter/veterinária , Campylobacter/patogenicidade , Galinhas , Doenças das Aves Domésticas/epidemiologia , Doenças das Aves Domésticas/virologia , Resistência a Tetraciclina , Animais , Campylobacter/genética , Infecções por Campylobacter/epidemiologia , Impressões Digitais de DNA , Primers do DNA/genética , Eletroforese em Gel de Campo Pulsado , Prevalência
18.
Dev Biol ; 314(2): 351-61, 2008 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-18191829

RESUMO

Rohon-Beard mechanosensory neurons (RBs), neural crest cells, and neurogenic placodes arise at the border of the neural- and non-neural ectoderm during anamniote vertebrate development. Neural crest cells require BMP expressing non-neural ectoderm for their induction. To determine if epidermal ectoderm-derived BMP signaling is also involved in the induction of RB sensory neurons, the medial region of the neural plate from donor Xenopus laevis embryos was transplanted into the non-neural ventral ectoderm of host embryos at the same developmental stage. The neural plate border and RBs were induced at the transplant sites, as shown by expression of Xblimp1, and XHox11L2 and XN-tubulin, respectively. Transplantation studies between pigmented donors and albino hosts showed that neurons are induced both in donor neural and host epidermal tissue. Because an intermediate level of BMP4 signaling is required to induce neural plate border fates, we directly tested BMP4's ability to induce RBs; beads soaked in either 1 or 10 ng/ml were able to induce RBs in cultured neural plate tissue. Conversely, RBs fail to form when neural plate tissue from embryos with decreased BMP activity, either from injection of noggin or a dominant negative BMP receptor, was transplanted into the non-neural ectoderm of un-manipulated hosts. We conclude that contact between neural and non-neural ectoderm is capable of inducing RBs, that BMP4 can induce RB markers, and that BMP activity is required for induction of ectopic RB sensory neurons.


Assuntos
Proteínas Morfogenéticas Ósseas/fisiologia , Ectoderma/fisiologia , Embrião não Mamífero/fisiologia , Neurônios Aferentes/classificação , Neurônios Aferentes/fisiologia , Animais , Proteína Morfogenética Óssea 4 , Desenvolvimento Embrionário/fisiologia , Placa Neural/fisiologia , Proteínas de Xenopus/fisiologia , Xenopus laevis/embriologia
19.
Alcohol Clin Exp Res ; 29(11): 2053-62, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16340464

RESUMO

BACKGROUND: Prenatal ethanol exposure results in a spectrum of cognitive and behavioral deficits and affects an estimated thirteen percent of children born in the United States. The basis of prenatal ethanol-induced impairment of brain function has been widely studied in animal models, where significant changes in the physiological and structural plasticity of hippocampal function have been documented. Here, we explored the possibility that exposure to moderate levels of alcohol in utero might also result in long-lasting impairment of adult hippocampal neurogenesis, a novel form of plasticity that occurs throughout adulthood. METHODS: Female mice were trained to voluntarily consume 10% EtOH throughout pregnancy using the two-bottle choice paradigm, which results in moderate blood alcohol levels of approximately 121 mg/dl, as previously described (Allan et al., 2003). Offspring were exposed to standard or enriched living conditions for 8-12 weeks post-weaning. BrdU was administered at 50 mg/kg for 12 consecutive days. Mice in each housing condition were sacrificed at either 24 hrs or four weeks following the final BrdU injection, and BrdU cells within the dentate gyrus were evaluated using immuno-histochemical methods. RESULTS: Neither fetal alcohol exposure (FAE) nor enriched environment affected the number of proliferating progenitors within the subgranular zone (SGZ) of the dentate gyrus. However, FAE severely impaired the neurogenic response to enriched environment. Control mice housed in enriched environment displayed a two-fold increase in hippocampal neurogenesis, whereas FAE mice responded to enriched environment with neither enhanced progenitor survival nor enhanced neuronal differentiation. CONCLUSIONS: These observations indicate that moderate FAE results in a long-term, persistent defect in neurogenic responses to behavioral challenge.


Assuntos
Giro Denteado/efeitos dos fármacos , Etanol/toxicidade , Feto/efeitos dos fármacos , Hipocampo/fisiologia , Abrigo para Animais , Plasticidade Neuronal/efeitos dos fármacos , Efeitos Tardios da Exposição Pré-Natal , Animais , Bromodesoxiuridina/farmacologia , Giro Denteado/metabolismo , Giro Denteado/fisiologia , Modelos Animais de Doenças , Planejamento Ambiental , Etanol/sangue , Feminino , Transtornos do Espectro Alcoólico Fetal/metabolismo , Desenvolvimento Fetal/efeitos dos fármacos , Desenvolvimento Fetal/fisiologia , Feto/fisiologia , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Abrigo para Animais/normas , Imuno-Histoquímica , Troca Materno-Fetal , Camundongos , Plasticidade Neuronal/fisiologia , Gravidez
20.
Dev Biol ; 278(2): 347-57, 2005 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-15680355

RESUMO

Specification of both neural crest cells and Rohon-Beard (RB) sensory neurons involves a complex series of interactions between the neural and non-neural ectoderm. The molecular mechanisms directing this process are not well understood. The zebrafish narrowminded (nrd) mutation is unique, since it is one of two mutations in which defects are observed in both cell populations: it leads to a complete absence of RB neurons and a reduction in neural crest cells and their derivatives. Here, we show that nrd is a mutation in prdm1, a SET/zinc-finger domain transcription factor. A Morpholino-mediated depletion of prdm1 phenocopies the nrd mutation, and conversely overexpression of prdm1 mRNA rescues the nrd RB sensory neuron and neural crest phenotype. prdm1 is expressed at the border of the neural plate within the domain where neural crest cells and RB sensory neurons form. Analysis of prdm1 function by overexpression indicates that prdm1 functions to promote the cell fate specification of both neural crest cells and RB sensory neurons, most likely as a downstream effector of the BMP signaling pathway.


Assuntos
Proteínas do Tecido Nervoso/genética , Crista Neural/fisiologia , Neurônios Aferentes/citologia , Proteínas Repressoras/genética , Fatores de Transcrição/genética , Proteínas de Peixe-Zebra/genética , Peixe-Zebra/embriologia , Animais , Sequência de Bases , Fatores de Transcrição Hélice-Alça-Hélice Básicos , Mapeamento Cromossômico , Primers do DNA , Proteínas de Ligação a DNA , Embrião não Mamífero/fisiologia , Hibridização In Situ , Proteínas Nucleares , Fator 1 de Ligação ao Domínio I Regulador Positivo , Mapeamento por Restrição , Dedos de Zinco
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