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1.
Molecules ; 27(23)2022 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-36500349

RESUMO

A series of boron, aluminum, gallium, and indium chelates containing the underexplored bis(phenolate) aza-dipyrromethene (aza-DIPY) core were prepared. These compounds were found to possess near-infrared absorption and emission profiles in the 710 to 770 nm domain and exhibit quantum yield values up to 14%. X-ray diffraction analysis revealed that heavier group 13 bis(phenolate) aza-DIPY chelates possessed octahedral geometries with either THF or pyridine groups occupying the axial positions as opposed to the tetrahedral geometry of the boron chelate.


Assuntos
Compostos de Boro , Corantes Fluorescentes , Cristalografia por Raios X , Fenóis , Quelantes
2.
Chempluschem ; 84(9): 1391-1395, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31944038

RESUMO

We have prepared nine structural isomers of a tetrakis(arylethynyl)benzene chromophore functionalized with 4-butoxyphenyl and pyridyl units as the respective donor and acceptor units and examined their steady-state spectroscopic parameters to study how small structural variations effect the electronic absorption and emission spectra. Unlike their 4-dibutylaminophenyl congeners that exhibited dynamic hypsochromic or bathochromic shifts in response to Lewis and Brønsted acids, the current class of compounds simply showed quenched fluorescence upon protonation; only AlCl3 elicited a red-shifted fluorescence response. Computational studies of each system were also performed to provide additional insight into the energy levels and electronic transitions present.

3.
Conn Med ; 81(3): 165-167, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29772163

RESUMO

In recentyears, theincidence ofvul- var carcinoma has increased over 400%, specifically in the population of young women. We present a patient with an extensive history of recurrent vulvar carcinoma in situ who underwent multiple surgi- cal procedures and subsequent reconstruction with a skin graft, who then returned with a rare recur- rence in the graft. Multiple hypotheses have been proposedto explain the recurrence ofthis type ofcar- cinoma; however, none provides a solid explanation. It has been noted that the increase in the incidence of vulvar cancer correlates with the increased incidence of HPV infection; the relationship between the two has been well-established. In conclusion, we recommend close and long-term follow-up for high-risk patients with this type of neoplasm.


Assuntos
Carcinoma in Situ/patologia , Recidiva Local de Neoplasia/etiologia , Neoplasias Cutâneas/patologia , Transplante de Pele/efeitos adversos , Neoplasias Vulvares/patologia , Adulto , Carcinoma in Situ/etiologia , Carcinoma in Situ/cirurgia , Feminino , Humanos , Recidiva Local de Neoplasia/patologia , Neoplasias Cutâneas/etiologia , Neoplasias Cutâneas/cirurgia , Neoplasias Vulvares/etiologia , Neoplasias Vulvares/cirurgia
4.
Neuron ; 92(5): 1049-1062, 2016 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-27866800

RESUMO

Little is known about how animals integrate multiple sensory inputs in natural environments to balance avoidance of danger with approach to things of value. Furthermore, the mechanistic link between internal physiological state and threat-reward decision making remains poorly understood. Here we confronted C. elegans worms with the decision whether to cross a hyperosmotic barrier presenting the threat of desiccation to reach a source of food odor. We identified a specific interneuron that controls this decision via top-down extrasynaptic aminergic potentiation of the primary osmosensory neurons to increase their sensitivity to the barrier. We also establish that food deprivation increases the worm's willingness to cross the dangerous barrier by suppressing this pathway. These studies reveal a potentially general neural circuit architecture for internal state control of threat-reward decision making.


Assuntos
Tomada de Decisões/fisiologia , Fome/fisiologia , Interneurônios/fisiologia , Animais , Comunicação Autócrina/fisiologia , Caenorhabditis elegans , Retroalimentação , Modelos Neurológicos , Rede Nervosa , Neurônios/fisiologia , Neuropeptídeos/metabolismo , Recompensa
5.
Conserv Physiol ; 4(1): cow013, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27293761

RESUMO

Reintroduction of endangered fishes to historic habitat has been used as a recovery tool; however, these fish may face competition from other fishes that established in their native habitat since extirpation. This study investigated the physiological response of tidewater goby, Eucyclogobius newberryi, an endangered California fish, when competing for food with threespine stickleback, Gasterosteus aculeatus, a native species, and rainwater killifish, Lucania parva, a non-native species. Survival, growth and physiological indicators of stress (i.e. cortisol, glucose and lactate concentrations) were assessed for juvenile fish held for 28 days in two food-limited conditions. When fed a 75% ration, survival of E. newberryi was significantly lower when held with G. aculeatus. In all fish assemblages, weight and relative condition decreased then stabilized over the 28 day experiment, while length remained unchanged. Whole-body cortisol in E. newberryi was not affected by fish assemblage; however, glucose and lactate concentrations were significantly higher with conspecifics than with other fish assemblages. When fed a 50% ration, survival of E. newberryi decreased during the second half of the experiment, while weight and relative condition decreased and length remained unchanged in all three fish assemblages. Cortisol concentrations were significantly higher for all fish assemblages compared with concentrations at the start of the experiment, whereas glucose and lactate concentrations were depressed relative to concentrations at the start of the experiment, with the magnitude of decrease dependent on the species assemblage. Our findings indicate that E. newberryi exhibited reduced growth and an elevated generalized stress response during low food availability. In response to reduced food availability, competition with G. aculeatus had the greatest physiological effect on E. newberryi, with minimal effects from the non-native L. parva. This study presents the first reported cortisol, glucose and lactate concentrations in response to chronic stress for E. newberryi.

6.
Acta Crystallogr E Crystallogr Commun ; 71(Pt 11): 1315-8, 2015 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-26594499

RESUMO

Treatment of carbon-yl(1,2-diphenylpenta-1,3-dien-1-yl-5-yl-idene)bis-(tri-phenyl-phosphane)iridium, [IrCO(-C(Ph)=C(Ph)-CH=CH-CH=)(PPh3)2], with either bromine or iodine produced di-bromido-(1,2-diphenylpenta-1,3-dien-1-yl-5-yl-idene)(tri-phenyl-phosphine)iridium(III), [IrBr2{-C(Ph)=C(Ph)-CH=CH-CH=}(PPh3)], (I), and (1,2-diphenylpenta-1,3-dien-1-yl-5-yl-idene)di-iodido-(tri-phenyl-phosphane)iridium(III), [IrI2{-C(Ph)=C(Ph)-CH=CH-CH=}(PPh3)], (II), respectively, which are two rare examples of 16-electron metalla-benzenes. Structural elucidation of (I) and (II) reveals that these isotypic irida-benzenes are unusual, not only in their electron count, but also in their coordination sphere of the Ir(III) atom where they contain an apparent open coordination site. The crystal structures of (I) and (II) confirm that the mol-ecules are complexes containing five-coordinated Ir(III) with only one tri-phenyl-phosphine group bound to the iridium atom, unambiguously proving that the mol-ecules are indeed 16-electron, high-oxidation-state irida-benzenes. The coordination geometry of the Ir(III) atom in both structures can be best described as a distorted square pyramid with the P, two Br (or I) and one C atom in the basal plane and another C atom in the apical position.

7.
Chem Sci ; 5(3): 1008-1014, 2014 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-24729855

RESUMO

The synthesis and characterization of four fully-conjugated indacenedithiophenes (IDTs) are disclosed. In contrast to anthradithiophenes, regioselective synthesis of both syn and anti isomers is readily achieved. Thiophene fusion imparts increased paratropic character on the central indacene core as predicted by DFT calculations and confirmed by 1H NMR spectroscopy. IDTs exhibit red-shifted absorbance maxima with respect to their all-carbon analogues and undergo two-electron reduction and one-electron oxidation.

8.
Org Lett ; 16(3): 812-5, 2014 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-24422680

RESUMO

A readily available N,N'-diamidocarbene (DAC) was found to insert into the P-H bonds of primary and secondary phosphines as well as a phosphonate ester. In contrast, tertiary phosphines catalyzed the ring contraction of the DAC to an iminopyrrolidinedione. Treating the DAC with trimethyl phosphite afforded the corresponding diamidophosphonate ester and olefinic products expected from an Arbuzov-type reaction.

9.
Top Curr Chem ; 349: 159-95, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-23097030

RESUMO

The growing demand for flexible electronic devices and hydrogen storage materials has spurred a resurgence of interest in polyaryl hydrocarbons including graphene, acenes, fullerenes, polythiophenes, etc. Indenofluorenes are another polyaryl molecular scaffold that has shown utility in the organic and hybrid materials arena, with polymers incorporating the indeno[1,2-b]fluorene moiety being common in organic light emitting diodes. This review examines the syntheses and properties of the five distinct indenofluorene regioisomers, with a focus on small molecule applications in organic electronics of this intriguing and somewhat underexplored family of polyaryl hydrocarbons.

10.
J Am Chem Soc ; 135(50): 18798-801, 2013 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-24303890

RESUMO

An N,N'-diamidocarbene (DAC) was found to activate a broad range of primary as well as secondary aliphatic and aromatic amines. The relative rates measured for the insertion of the DAC into the primary amines were consistent with an electrophilic activation mechanism; in contrast, the DAC functioned as a nucleophile upon treatment with secondary aryl amines. Collectively, these results constituted the first ambiphilic process for an isolable carbene. By comparison, an analogous diaminocarbene was found to serve exclusively as a nucleophile under similar conditions and led to the discovery of the first organic reagent to reversibly activate ammonia.

11.
J Vis Exp ; (79): e50693, 2013 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-24121477

RESUMO

RNA interference by feeding worms bacteria expressing dsRNAs has been a useful tool to assess gene function in C. elegans. While this strategy works well when a small number of genes are targeted for knockdown, large scale feeding screens show variable knockdown efficiencies, which limits their utility. We have deconstructed previously published RNAi knockdown protocols and found that the primary source of the reduced knockdown can be attributed to the loss of dsRNA-encoding plasmids from the bacteria fed to the animals. Based on these observations, we have developed a dsRNA feeding protocol that greatly reduces or eliminates plasmid loss to achieve efficient, high throughput knockdown. We demonstrate that this protocol will produce robust, reproducible knock down of C. elegans genes in multiple tissue types, including neurons, and will permit efficient knockdown in large scale screens. This protocol uses a commercially available dsRNA feeding library and describes all steps needed to duplicate the library and perform dsRNA screens. The protocol does not require the use of any sophisticated equipment, and can therefore be performed by any C. elegans lab.


Assuntos
Técnicas de Silenciamento de Genes/métodos , Interferência de RNA , RNA de Cadeia Dupla/administração & dosagem , Animais , Caenorhabditis elegans , Ensaios de Triagem em Larga Escala/métodos , Plasmídeos/administração & dosagem , Plasmídeos/genética , RNA de Cadeia Dupla/genética
12.
Genetics ; 194(2): 363-73, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23525334

RESUMO

We developed a novel knockdown strategy to examine cell-specific gene function in Caenorhabditis elegans. In this strategy a null mutation in any gene is replaced with a genetically stable transgene that contains a wild-type copy of the gene fused to a 3' tag that targets the mRNA transcript for degradation by the host nonsense-mediated decay (NMD) machinery. In NMD-defective animals, tagged transgene mRNA is expressed at levels similar to the endogenous gene it replaced and is translated into wild-type protein that fully rescues gene function. Cell-specific activation of NMD cell autonomously knocks down transgene expression in specific cell types without affecting its expression or function in other cells of the organism. To demonstrate the utility of this system, we replaced the goa-1 gene, encoding the pan-neuronally expressed G-protein subunit GOA-1, with a degradation-tagged transgene. We then knocked down expression of the transgene from only two neurons, the hermaphrodite-specific neurons (HSNs), and showed that GOA-1 acts cell autonomously in the HSNs to inhibit egg-laying behavior.


Assuntos
Proteínas de Caenorhabditis elegans/genética , Caenorhabditis elegans/genética , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/genética , Técnicas de Silenciamento de Genes/métodos , Animais , Proteínas de Caenorhabditis elegans/metabolismo , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/metabolismo , Neurônios/metabolismo , Estabilidade de RNA , RNA Mensageiro/metabolismo , Transgenes/genética
13.
J Emerg Med ; 44(3): e303-6, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22883713

RESUMO

BACKGROUND: Uterine perforation is a rare but recognized complication of abortion. Perforations may not be recognized at the time of the procedure, and patients may present days or weeks later with sequelae of the complication. OBJECTIVES: To raise awareness of this rare complication that can present days to weeks after the precipitating event. CASE REPORT: A 21-year-old woman presented 3 weeks after an elective abortion with symptoms of bowel obstruction. Exploratory laparotomy revealed small bowel herniation into a perforated uterus, causing the obstruction. In retrospect, a pre-operative ultrasound and computed tomography (CT) scan suggested this finding, but it went unrecognized at that time. A small bowel resection was performed and the patient made an uneventful recovery. CONCLUSION: Intrauterine bowel after abortion has been described only a handful of times in the literature. Uterine perforation during abortion is usually asymptomatic and generally can be managed conservatively, but herniation of bowel through the uterine defect can result in obstruction and strangulation. Intrauterine bowel requires prompt laparotomy and possible resection of non-viable bowel. Although ultrasound and CT scans may aid in diagnosis of this rare complication, a clinical suspicion for uterine perforation should be maintained by health care providers when treating patients who have had an abortion.


Assuntos
Aborto Induzido/efeitos adversos , Dilatação e Curetagem/efeitos adversos , Hérnia/complicações , Obstrução Intestinal/etiologia , Perfuração Uterina/etiologia , Procedimentos Cirúrgicos Eletivos , Feminino , Herniorrafia , Humanos , Obstrução Intestinal/diagnóstico por imagem , Obstrução Intestinal/cirurgia , Laparotomia , Gravidez , Segundo Trimestre da Gravidez , Tomografia Computadorizada por Raios X , Perfuração Uterina/complicações , Perfuração Uterina/diagnóstico por imagem , Adulto Jovem
15.
Org Lett ; 14(21): 5510-3, 2012 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-23094710

RESUMO

The reversible [2 + 1] cycloadditions between an N,N'-diamidocarbene (DAC) and eight aldehydes were examined using NMR spectroscopy. Variable temperature magnetization transfer experiments revealed higher exchange rates and lower activation barriers when electron-deficient aldehydes were employed. Likewise, competitive equilibrium studies indicated a thermodynamic preference for electron-deficient aryl and sterically unhindered alkyl aldehydes compared to more electron-rich or bulkier substrates. Collectively, these and other data collected were consistent with the oxiranation process proceeding in an asynchronous manner.

16.
J Am Chem Soc ; 134(25): 10349-52, 2012 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-22697518

RESUMO

Herein we report the synthesis and characterization of a series of 6,12-diarylindeno[1,2-b]fluorenes (IFs). Functionalization with electron donor and acceptor groups influences the ability of the IF scaffold to undergo two-electron oxidation and reduction to yield the corresponding 18- and 22-π-electron species, respectively. A single crystal of the pentafluorophenyl-substituted IF can serve as an active layer in an organic field-effect transistor (OFET). The important finding is that the single-crystal OFET yields an ambipolar device that is able to transport holes and electrons.

17.
PLoS One ; 7(5): e37831, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22629462

RESUMO

Dopamine signaling modulates voluntary movement and reward-driven behaviors by acting through G protein-coupled receptors in striatal neurons, and defects in dopamine signaling underlie Parkinson's disease and drug addiction. Despite the importance of understanding how dopamine modifies the activity of striatal neurons to control basal ganglia output, the molecular mechanisms that control dopamine signaling remain largely unclear. Dopamine signaling also controls locomotion behavior in Caenorhabditis elegans. To better understand how dopamine acts in the brain we performed a large-scale dsRNA interference screen in C. elegans for genes required for endogenous dopamine signaling and identified six genes (eat-16, rsbp-1, unc-43, flp-1, grk-1, and cat-1) required for dopamine-mediated behavior. We then used a combination of mutant analysis and cell-specific transgenic rescue experiments to investigate the functional interaction between the proteins encoded by two of these genes, eat-16 and rsbp-1, within single cell types and to examine their role in the modulation of dopamine receptor signaling. We found that EAT-16 and RSBP-1 act together to modulate dopamine signaling and that while they are coexpressed with both D1-like and D2-like dopamine receptors, they do not modulate D2 receptor signaling. Instead, EAT-16 and RSBP-1 act together to selectively inhibit D1 dopamine receptor signaling in cholinergic motor neurons to modulate locomotion behavior.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Reguladores de Proteínas de Ligação ao GTP/metabolismo , Proteínas de Membrana/metabolismo , Atividade Motora/fisiologia , Neurônios Motores/metabolismo , Receptores de Dopamina D1/metabolismo , Transdução de Sinais/fisiologia , Animais , Animais Geneticamente Modificados , Comportamento Animal/fisiologia , Caenorhabditis elegans , Proteínas de Caenorhabditis elegans/genética , Neurônios Colinérgicos/metabolismo , Reguladores de Proteínas de Ligação ao GTP/genética , Proteínas de Membrana/genética , Receptores de Dopamina D2
19.
J Fam Pract ; 60(7): 404-9, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21731918

RESUMO

Motion-controlled game consoles like Wii may be used to play virtual sports, but the injuries associated with them are real. Here's what to watch for--and a handy table linking specific games to particular injuries.


Assuntos
Jogos de Vídeo/efeitos adversos , Revelação , Humanos , Incidência , Estados Unidos/epidemiologia , Ferimentos e Lesões/classificação , Ferimentos e Lesões/epidemiologia , Ferimentos e Lesões/etiologia
20.
JPEN J Parenter Enteral Nutr ; 35(5): 625-9, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21799186

RESUMO

INTRODUCTION: A critical review of the pulmonary complications associated with blind placement of narrow-bore nasoenteric tubes (NETs) is discussed. Preventive measures and placement techniques are addressed to decrease patient morbidity and mortality. METHODS: A thorough database review was conducted to identify all randomized controlled and retrospective trials specifically addressing pulmonary complications from narrow-bore NET placement. Five unique studies, comprising more than 9900 NET placements, were identified. On the basis of the literature reviewed, the authors identified 3 major complications associated with blind NET placement: patient mortality directly resulting from NET misplacement, incidence of tracheopulmonary malpositioning, and correlation between NET misplacement and mechanical ventilation. RESULTS: Of the 9931 NET placements reviewed, there were 187 total improper tube placements in the tracheobronchial tree, which translates to a 1.9% mean overall malposition rate. Of these 187 misplacements, there were 35 (18.7%) reported pneumothoraces, at least 5 of which resulted in patient death. NET malpositioning was reported in 13%-32% of subsequent repositioning attempts. This increased risk exposes the patient population to a cumulative mortality from tracheobronchial malpositioning approaching >20%. Unexpectedly, of the 187 total misplacements, 113 (60.4%) of the patients were mechanically ventilated. CONCLUSIONS: Practitioners need to be aware of the potential for pulmonary complications associated with blind NET placement. Changes in institutional protocol should be considered to minimize unnecessary risks. As with any procedure, experienced personnel should be primarily used for tube placement and responsible for assisting others with less familiarity to learn the proper methods.


Assuntos
Nutrição Enteral/efeitos adversos , Intubação Gastrointestinal/efeitos adversos , Intubação Gastrointestinal/métodos , Nutrição Enteral/métodos , Humanos , Pneumotórax/diagnóstico por imagem , Pneumotórax/etiologia , Radiografia , Ensaios Clínicos Controlados Aleatórios como Assunto , Respiração Artificial , Fatores de Risco , Resultado do Tratamento
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