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1.
Semin Cell Dev Biol ; 142: 13-22, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-35623984

RESUMO

The generation of neuronal diversity involves temporal patterning mechanisms by which a given progenitor sequentially produces multiple cell types. Several parallels are evident between the brain development programs of Drosophila and vertebrates, such as the successive emergence of specific cell types and the use of combinations of transcription factors to specify cell fates. Furthermore, cell-extrinsic cues such as hormones and signaling pathways have also been shown to be regulatory modules of temporal patterning. Recently, transcriptomic and epigenomic studies using large single-cell sequencing datasets have provided insights into the transcriptional dynamics of neurogenesis in the Drosophila and mammalian central nervous systems. We review these commonalities in the specification of neuronal identity and highlight the conserved or convergent strategies of brain development by discussing temporal patterning mechanisms found in flies and vertebrates.


Assuntos
Proteínas de Drosophila , Drosophila , Animais , Drosophila/metabolismo , Vertebrados/metabolismo , Neurônios/metabolismo , Sistema Nervoso Central/metabolismo , Proteínas de Drosophila/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Mamíferos/metabolismo
2.
J Pediatr Psychol ; 49(4): 247-258, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-37654097

RESUMO

OBJECTIVES: We investigated whether the self-system belief of fear of abandonment mediated the effects of intervention-induced change in 2 protective factors-positive parenting and adaptive coping-and one risk factor-stressful events-on youth mental health problems and maladaptive grief. This study extends prior research on fear of abandonment in youth who experience parental death by examining pathways through which a program reduced fear of abandonment and, in turn, affected subsequent pathways to child mental health problems in the context of a randomized experiment. METHODS: This is a secondary data analysis study. We used data from the 4-wave longitudinal 2-arm parallel randomized controlled trial of the Family Bereavement Program conducted between 1996 and 1999 in a large city in the Southwestern United States. The sample consisted of 244 offspring between 8 and 16 at the pretest. They were assessed again at posttest, 11-month follow-up, and 6-year follow-up. Offspring, caregivers, and teachers provided data. RESULTS: Mediation analyses indicated that intervention-induced reductions in stressful events were prospectively associated with a lower fear of abandonment. For girls, fear of abandonment was related to self-reported maladaptive grief and teacher-reported internalizing problems 6 years later. CONCLUSIONS: This study extends prior research on the relation between intervention-induced changes in risk and protective factors and improvements in outcomes of bereaved youth. The findings support the reduction of stressful events as a key proximal target of prevention programs for bereaved children.


Assuntos
Luto , Saúde Mental , Criança , Feminino , Humanos , Adolescente , Pesar , Poder Familiar/psicologia , Medo
3.
Dev Psychopathol ; 35(5): 2482-2498, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37559382

RESUMO

This study evaluated whether the Family Bereavement Program (FBP), a prevention program for parentally bereaved families, improved parenting attitudes toward parental warmth and physical punishment in young adult offspring 15 years after participation and identified mediational cascade pathways. One hundred fifty-six parents and their 244 offspring participated. Data were collected at pretest (ages 8-16), posttest, and six- and 15-year follow-ups. Ethnicity of offspring was: 67% non-Hispanic Caucasian, 16% Hispanic, 7% African American, 3% Native American, 1% Asian or Pacific Islander, and 6% other; 54% were males. There was a direct effect of the FBP on attitudes toward physical punishment; offspring in the FBP had less favorable attitudes toward physical punishment. There were also indirect effects of the FBP on parenting attitudes. The results supported a cascade effects model in which intervention-induced improvements in parental warmth led to fewer externalizing problems in adolescence/emerging adulthood, which in turn led to less favorable attitudes toward physical punishment. In addition, intervention-induced improvements in parental warmth led to improvements in anxious romantic attachment in mid-to-late adolescence/emerging adulthood, which led to more favorable attitudes toward parental warmth in emerging/young adulthood. These findings suggest that the effects of relatively brief prevention programs may persist into subsequent generations.


Assuntos
Luto , Poder Familiar , Masculino , Adolescente , Adulto Jovem , Humanos , Adulto , Feminino , Pais , Atitude , Ansiedade
4.
Chemistry ; 28(51): e202200953, 2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-35749651

RESUMO

An enzymatic biosensor has been developed for the determination of selenate (SeO4 2- ), in which selenate reductase (SeR) is chemically attached to a gold disk electrode by lipoic acid N-hydroxysuccinimide ester as linker, allowing the catalytic reduction of the SeO4 2- to SeO3 2- . Modification of the gold electrode was characterized by X-ray photoelectron spectroscopy (XPS), time-of-flight secondary ion mass spectroscopy (ToF-SIMS), and electrochemistry. Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) measurements were performed in different buffers for selenate determination. Under optimum conditions, the calibration curve was linear over the range 7.0-3900.0 µg L-1 with limits of detection and quantification of 4.97 and 15.56 µg L-1 , respectively. The possible interference of the relevant oxyanions SO4 2- , NO3 - , NO2 - , PO4 3- and AsO4 3- in the determination of SeO4 2- was studied. Finally, the proposed biosensor was used to determine SeO4 2- with recovery between 95.2 and 102.4 % in different real water samples.


Assuntos
Técnicas Biossensoriais , Bactérias , Técnicas Biossensoriais/métodos , Eletroquímica/métodos , Eletrodos , Ouro/química , Ácido Selênico
5.
Proc Natl Acad Sci U S A ; 116(23): 11508-11517, 2019 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-31097585

RESUMO

Opsins form a family of light-activated, retinal-dependent, G protein-coupled receptors (GPCRs) that serve a multitude of visual and nonvisual functions. Opsin 3 (OPN3 or encephalopsin), initially identified in the brain, remains one of the few members of the mammalian opsin family with unknown function and ambiguous light absorption properties. We recently discovered that OPN3 is highly expressed in human epidermal melanocytes (HEMs)-the skin cells that produce melanin. The melanin pigment is a critical defense against ultraviolet radiation (UVR), and its production is mediated by the Gαs-coupled melanocortin 1 receptor (MC1R). The physiological function and light sensitivity of OPN3 in melanocytes are yet to be determined. Here, we show that in HEMs, OPN3 acts as a negative regulator of melanin production by modulating the signaling of MC1R. OPN3 negatively regulates the cyclic adenosine monophosphate (cAMP) response evoked by MC1R via activation of the Gαi subunit of G proteins, thus decreasing cellular melanin levels. In addition to their functional relationship, OPN3 and MC1R colocalize at both the plasma membrane and in intracellular structures, and can form a physical complex. Remarkably, OPN3 can bind retinal, but does not mediate light-induced signaling in melanocytes. Our results identify a function for OPN3 in the regulation of the melanogenic pathway in epidermal melanocytes; we have revealed a light-independent function for the poorly characterized OPN3 and a pathway that greatly expands our understanding of melanocyte and skin physiology.


Assuntos
Epiderme/metabolismo , Melanócitos/metabolismo , Pigmentação/fisiologia , Receptor Tipo 1 de Melanocortina/metabolismo , Opsinas de Bastonetes/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Membrana Celular/metabolismo , AMP Cíclico/metabolismo , Proteínas de Ligação ao GTP/metabolismo , Células HEK293 , Células HeLa , Humanos , Melaninas/metabolismo , Transdução de Sinais/fisiologia , Pele/metabolismo
6.
Faraday Discuss ; 230(0): 172-186, 2021 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-33876167

RESUMO

A proof-of-concept for the carbonation-assisted processing of ultramafic nickel ores is presented. Carbonation converts serpentine, the primary gangue or undesirable mineral, to magnesite. It prevents slime coating of fine gangue minerals on pentlandite, the main nickel-bearing mineral, during froth flotation, and improves nickel recovery and concentrate grade. Additionally, CO2 is captured and stored in the form of solid carbonates, thus removing it from the atmosphere. Microflotation experiments demonstrated improved nickel recovery (61.2 to 87.4 wt%) and concentrate grade (20.6 to 24.7 wt%) in carbonated vs. uncarbonated systems. The mechanism behind the improved nickel flotation was investigated by zeta potential measurements, optical imaging microscopy, X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry. These analyses confirmed the absence of slime coating in the carbonated system under the flotation conditions tested. Finally, a preliminary techno-economic analysis was performed to evaluate the cost metrics of incorporating carbonation into nickel mineral processing.

7.
Nature ; 507(7492): 358-61, 2014 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-24572358

RESUMO

How specific features in the environment are represented within the brain is an important unanswered question in neuroscience. A subset of retinal neurons, called direction-selective ganglion cells (DSGCs), are specialized for detecting motion along specific axes of the visual field. Despite extensive study of the retinal circuitry that endows DSGCs with their unique tuning properties, their downstream circuitry in the brain and thus their contribution to visual processing has remained unclear. In mice, several different types of DSGCs connect to the dorsal lateral geniculate nucleus (dLGN), the visual thalamic structure that harbours cortical relay neurons. Whether direction-selective information computed at the level of the retina is routed to cortical circuits and integrated with other visual channels, however, is unknown. Here we show that there is a di-synaptic circuit linking DSGCs with the superficial layers of the primary visual cortex (V1) by using viral trans-synaptic circuit mapping and functional imaging of visually driven calcium signals in thalamocortical axons. This circuit pools information from several types of DSGCs, converges in a specialized subdivision of the dLGN, and delivers direction-tuned and orientation-tuned signals to superficial V1. Notably, this circuit is anatomically segregated from the retino-geniculo-cortical pathway carrying non-direction-tuned visual information to deeper layers of V1, such as layer 4. Thus, the mouse harbours several functionally specialized, parallel retino-geniculo-cortical pathways, one of which originates with retinal DSGCs and delivers direction- and orientation-tuned information specifically to the superficial layers of the primary visual cortex. These data provide evidence that direction and orientation selectivity of some V1 neurons may be influenced by the activation of DSGCs.


Assuntos
Vias Neurais/fisiologia , Células Ganglionares da Retina/citologia , Células Ganglionares da Retina/fisiologia , Córtex Visual/citologia , Córtex Visual/fisiologia , Animais , Axônios/fisiologia , Sinalização do Cálcio , Corpos Geniculados/citologia , Corpos Geniculados/fisiologia , Células HEK293 , Humanos , Camundongos , Orientação/fisiologia , Vírus da Raiva/genética , Vírus da Raiva/fisiologia , Tálamo/citologia , Tálamo/fisiologia
8.
Curr Microbiol ; 77(7): 1233-1244, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32123985

RESUMO

Persisters of infectious agents are capable of surviving antibiotic treatment so the emergence of these subpopulations need to be overcome. In this study, we aimed to isolate, characterize and inhibit persister subpopulation in two clinical isolates Klebsiella pneumoniae and Proteus mirabilis. Different behavior profiles between the two isolates could be observed. The results of dose-dependent killing curve revealed that 2.3% (Klebsiella pneumoniae) versus 1.3% (Proteus mirabilis) persister cells could be recovered using 500 and 30 ug/ml ciprofloxacin, respectively. Upon resuscitation, persister cells exhibited only 65% versus 30% percentage growth and 5 versus 7 times cell elongation relative to Klebsiella pneumoniae and Proteus mirabilis, respectively. The levels of persister cells to ciprofloxacin of Klebsiella pneumoniae were dramatically decreased by about 79, 92, 97 and 83% in average by pre-exposure to hyperosmotic stress, temperature, different pHs, and hydrogen peroxide, respectively, while those of Proteus mirabilis were minimally decreased with corresponding reduction percentages of about 12%, 24 & 25%, and 0%. Regarding combating persisters, Klebsiella pneumoniae showed different response as compared to Proteus mirabilis. Among the tested sugars, the highest reduction of Klebsiella pneumoniae persister cells was obtained with pre-priming with sucrose while for Proteus mirabilis persister cells, the highest reduction was obtained with pre-priming with glucose. Using sodium salicylate with ciprofloxacin could eradicate persisters of Klebsiella pneumoniae at any tested concentration while for Proteus mirabilis it caused some reduction in persister cells at certain concentrations. Complete eradication of persisters was obtained by combining silver nitrate with ciprofloxacin for each test isolate.


Assuntos
Antibacterianos/farmacologia , Klebsiella pneumoniae , Proteus mirabilis , Ciprofloxacina/farmacologia , Farmacorresistência Bacteriana/fisiologia , Humanos , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/fisiologia , Testes de Sensibilidade Microbiana , Infecções por Proteus/microbiologia , Proteus mirabilis/efeitos dos fármacos , Proteus mirabilis/fisiologia , Estresse Fisiológico/fisiologia
9.
Kathmandu Univ Med J (KUMJ) ; 18(72): 329-332, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-34165086

RESUMO

Background The global health community has emphasized the importance of reporting epidemiological data by age and sex groups in the COVID-19 pandemic. However, age and sex disaggregated data of COVID-19 cases and deaths are rarely reported. Such data are very crucial for public to make truly informed choices about their own diseases risk and also for governments for public policy response. Objective To assess age and gender difference among COVID-19 cases and deaths in Nepal. Method This is a retrospective study which uses public data on COVID-19 cases and deaths released by Ministry of Health and Population, Government of Nepal from January to November, 2020. The data analysis was carried out using SPPS software version 26. Result Nepal reported 233,452 confirmed cases and 1,566 deaths of COVID-19 from 23 January 2020 to 30 November 2020. We found statistically significant differences on COVID-19 cases by age and gender in Nepal with higher number of cases among males of economically active age groups (20-60 years). Similarly, we found significant difference in COVID-19 mortality with more death occurred among male group compared to female group and with highest number of deaths among the people of above 60 years. Furthermore, we found differences in cases and deaths among provinces. Conclusion The age and gender differences in COVID cases and deaths in Nepal indicates needs of considering age and sex groups seriously while planning for testing, case management and vaccination against COVID-19 infections in Nepal.


Assuntos
COVID-19 , Caracteres Sexuais , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Morbidade , Nepal/epidemiologia , Pandemias , Estudos Retrospectivos , SARS-CoV-2 , Adulto Jovem
10.
J Sci Food Agric ; 97(14): 4780-4789, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28369913

RESUMO

BACKGROUND: Accumulation of lead (Pb) in agricultural soils has become a major factor for reduced crop yields and poses serious threats to humans consuming agricultural products. The present study investigated the effects of KNO3 seed priming (0 and 0.5% KNO3 ) on growth of maize (Zea mays L.) seedlings exposed to Pb toxicity (0, 1300 and 2550 mg kg-1 Pb). RESULTS: Pb exposure markedly reduced the growth of maize seedlings and resulted in higher Pb accumulation in roots than shoots. Pretreatment of seeds with KNO3 significantly improved the germination percentage and increased physiological indices. A stimulating effect of KNO3 seed priming was also observed on pigments (chlorophyll a, b, total chlorophyll and carotenoid contents) of Pb-stressed plants. Low translocation of Pb from roots to shoots caused an increased accumulation of total free amino acids and higher activities of catalase, peroxidase, superoxide dismutase and ascorbate peroxidase in roots as compared to shoot, which were further enhanced by exogenous KNO3 supply to prevent Pb toxicity. CONCLUSION: Maize accumulates more Pb in roots than shoot at early growth stages. Priming of seeds with KNO3 prevents Pb toxicity, which may be exploited to improve seedling establishment in crop species grown under Pb contaminated soils. © 2017 Society of Chemical Industry.


Assuntos
Chumbo/toxicidade , Nitratos/farmacologia , Compostos de Potássio/farmacologia , Sementes/efeitos dos fármacos , Sementes/crescimento & desenvolvimento , Zea mays/efeitos dos fármacos , Antioxidantes/análise , Antioxidantes/metabolismo , Carotenoides/análise , Clorofila/análise , Contaminação de Alimentos/prevenção & controle , Germinação/efeitos dos fármacos , Chumbo/análise , Raízes de Plantas/química , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Poluentes do Solo/análise , Zea mays/crescimento & desenvolvimento
11.
J Neurosci ; 35(6): 2329-43, 2015 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-25673829

RESUMO

Retinal ganglion cell (RGC) loss is a hallmark of glaucoma and the second leading cause of blindness worldwide. The type and timing of cellular changes leading to RGC loss in glaucoma remain incompletely understood, including whether specific RGC subtypes are preferentially impacted at early stages of this disease. Here we applied the microbead occlusion model of glaucoma to different transgenic mouse lines, each expressing green fluorescent protein in 1-2 specific RGC subtypes. Targeted filling, reconstruction, and subsequent comparison of the genetically identified RGCs in control and bead-injected eyes revealed that some subtypes undergo significant dendritic rearrangements as early as 7 d following induction of elevated intraocular pressure (IOP). By comparing specific On-type, On-Off-type and Off-type RGCs, we found that RGCs that target the majority of their dendritic arbors to the scleral half or "Off" sublamina of the inner plexiform layer (IPL) undergo the greatest changes, whereas RGCs with the majority of their dendrites in the On sublamina did not alter their structure at this time point. Moreover, M1 intrinsically photosensitive RGCs, which functionally are On RGCs but structurally stratify their dendrites in the Off sublamina of the IPL, also underwent significant changes in dendritic structure 1 week after elevated IOP. Thus, our findings reveal that certain RGC subtypes manifest significant changes in dendritic structure after very brief exposure to elevated IOP. The observation that RGCs stratifying most of their dendrites in the Off sublamina are first to alter their structure may inform the development of new strategies to detect, monitor, and treat glaucoma in humans.


Assuntos
Dendritos/patologia , Glaucoma/patologia , Células Ganglionares da Retina/patologia , Animais , Encéfalo/patologia , Morte Celular/fisiologia , Tamanho Celular , Progressão da Doença , Feminino , Pressão Intraocular/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Retina/patologia
13.
J Neurosci ; 33(11): 4642-56, 2013 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-23486939

RESUMO

The thalamus is crucial in determining the sensory information conveyed to cortex. In the visual system, the thalamic lateral geniculate nucleus (LGN) is generally thought to encode simple center-surround receptive fields, which are combined into more sophisticated features in cortex, such as orientation and direction selectivity. However, recent evidence suggests that a more diverse set of retinal ganglion cells projects to the LGN. We therefore used multisite extracellular recordings to define the repertoire of visual features represented in the LGN of mouse, an emerging model for visual processing. In addition to center-surround cells, we discovered a substantial population with more selective coding properties, including direction and orientation selectivity, as well as neurons that signal absence of contrast in a visual scene. The direction and orientation selective neurons were enriched in regions that match the termination zones of direction selective ganglion cells from the retina, suggesting a source for their tuning. Together, these data demonstrate that the mouse LGN contains a far more elaborate representation of the visual scene than current models posit. These findings should therefore have a significant impact on our understanding of the computations performed in mouse visual cortex.


Assuntos
Mapeamento Encefálico , Corpos Geniculados/citologia , Neurônios/fisiologia , Vias Visuais/fisiologia , Percepção Visual/fisiologia , Potenciais de Ação , Animais , Biofísica , Feminino , Fatores de Transcrição Forkhead/metabolismo , Corpos Geniculados/fisiologia , Proteínas de Fluorescência Verde , Técnicas In Vitro , Indóis/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Estimulação Luminosa , Proteínas Repressoras/metabolismo , Células Ganglionares da Retina/fisiologia , Versicanas/metabolismo , Campos Visuais/fisiologia
14.
J Neurosci ; 33(24): 10085-97, 2013 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-23761904

RESUMO

Neurons in layer VI of visual cortex represent one of the largest sources of nonretinal input to the dorsal lateral geniculate nucleus (dLGN) and play a major role in modulating the gain of thalamic signal transmission. However, little is known about how and when these descending projections arrive and make functional connections with dLGN cells. Here we used a transgenic mouse to visualize corticogeniculate projections to examine the timing of cortical innervation in dLGN. Corticogeniculate innervation occurred at postnatal ages and was delayed compared with the arrival of retinal afferents. Cortical fibers began to enter dLGN at postnatal day 3 (P3) to P4, a time when retinogeniculate innervation is complete. However, cortical projections did not fully innervate dLGN until eye opening (P12), well after the time when retinal inputs from the two eyes segregate to form nonoverlapping eye-specific domains. In vitro thalamic slice recordings revealed that newly arriving cortical axons form functional connections with dLGN cells. However, adult-like responses that exhibited paired pulse facilitation did not fully emerge until 2 weeks of age. Finally, surgical or genetic elimination of retinal input greatly accelerated the rate of corticogeniculate innervation, with axons invading between P2 and P3 and fully innervating dLGN by P8 to P10. However, recordings in genetically deafferented mice showed that corticogeniculate synapses continued to mature at the same rate as controls. These studies suggest that retinal and cortical innervation of dLGN is highly coordinated and that input from retina plays an important role in regulating the rate of corticogeniculate innervation.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Corpos Geniculados/fisiologia , Retina/fisiologia , Córtex Visual/fisiologia , Vias Visuais/fisiologia , Fatores Etários , Análise de Variância , Animais , Animais Recém-Nascidos , Fatores de Transcrição Hélice-Alça-Hélice Básicos/deficiência , Toxina da Cólera/metabolismo , Potenciais Pós-Sinápticos Excitadores/fisiologia , Enucleação Ocular , Regulação da Expressão Gênica no Desenvolvimento/genética , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteína Básica da Mielina/genética , Proteínas do Tecido Nervoso/deficiência , Proteína Vesicular 1 de Transporte de Glutamato/metabolismo , Córtex Visual/citologia
15.
J Neurosci ; 33(45): 17797-813, 2013 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-24198370

RESUMO

When the head rotates, the image of the visual world slips across the retina. A dedicated set of retinal ganglion cells (RGCs) and brainstem visual nuclei termed the "accessory optic system" (AOS) generate slip-compensating eye movements that stabilize visual images on the retina and improve visual performance. Which types of RGCs project to each of the various AOS nuclei remain unresolved. Here we report a new transgenic mouse line, Hoxd10-GFP, in which the RGCs projecting to all the AOS nuclei are fluorescently labeled. Electrophysiological recordings of Hoxd10-GFP RGCs revealed that they include all three subtypes of On direction-selective RGCs (On-DSGCs), responding to upward, downward, or forward motion. Hoxd10-GFP RGCs also include one subtype of On-Off DSGCs tuned for forward motion. Retrograde circuit mapping with modified rabies viruses revealed that the On-DSGCs project to the brainstem centers involved in both horizontal and vertical retinal slip compensation. In contrast, the On-Off DSGCs labeled in Hoxd10-GFP mice projected to AOS nuclei controlling horizontal but not vertical image stabilization. Moreover, the forward tuned On-Off DSGCs appear physiologically and molecularly distinct from all previously genetically identified On-Off DSGCs. These data begin to clarify the cell types and circuits underlying image stabilization during self-motion, and they support an unexpected diversity of DSGC subtypes.


Assuntos
Tronco Encefálico/fisiologia , Percepção de Movimento/fisiologia , Retina/fisiologia , Vias Visuais/fisiologia , Percepção Visual/fisiologia , Animais , Movimentos Oculares/fisiologia , Camundongos , Camundongos Transgênicos , Estimulação Luminosa , Células Ganglionares da Retina/fisiologia
16.
J Neurosci ; 33(1): 35-51, 2013 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-23283320

RESUMO

The use of neurotropic viruses as transsynaptic tracers was first described in the 1960s, but only recently have such viruses gained popularity as a method for labeling neural circuits. The development of retrograde monosynaptic tracing vectors has enabled visualization of the presynaptic sources onto defined sets of postsynaptic neurons. Here, we describe the first application of a novel viral tracer, based on vesicular stomatitis virus (VSV), which directs retrograde transsynaptic viral spread between defined cell types. We use this virus in the mouse retina to show connectivity between starburst amacrine cells (SACs) and their known synaptic partners, direction-selective retinal ganglion cells, as well as to discover previously unknown connectivity between SACs and other retinal ganglion cell types. These novel connections were confirmed using physiological recordings. VSV transsynaptic tracing enables cell type-specific dissection of neural circuitry and can reveal synaptic relationships among neurons that are otherwise obscured due to the complexity and density of neuropil.


Assuntos
Rede Nervosa/fisiologia , Marcadores do Trato Nervoso/farmacologia , Neurônios/fisiologia , Retina/fisiologia , Sinapses/fisiologia , Animais , Camundongos , Rede Nervosa/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Retina/efeitos dos fármacos , Sinapses/efeitos dos fármacos , Vesiculovirus
17.
Front Surg ; 11: 1426170, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39381617

RESUMO

Introduction: This study explores the profound impact of nasal structure on individuals' self-image and emotional well-being, emphasizing the increasing popularity of rhinoplasty in Saudi Arabia, influenced by societal beauty standards portrayed on social media. The investigation aims to unravel the complex interplay between demographic factors, such as gender and age distribution, and prevalent nasal deformities in a cohort of 293 participants. Material and methods: This retrospective study at the University of Hail and King Khalid Hospital, Saudi Arabia, investigated nasal deformities in 293 participants aged 15-54. Ethical approval was obtained, and data, including bio-demographics and nasal deformities, were retrospectively reviewed. Statistical analyses, utilizing chi-square and Fisher exact tests, assessed associations, enhancing internal validity. The study targeted a diverse population, emphasizing ethical guidelines and systematic sampling. Results: Our study of 293 participants revealed a prevalence of common nasal deformities. Dorsal hump deformity (59.0%) was the most prevalent, followed by external nasal deviation (54.6%). Significant gender differences were observed, with males more prone to external nasal deviation (65.6%), while decreased nasal tip rotation was more common in females (40.6%). Variations in nasal tip shape were statistically significant, with broad nasal tip shape more prevalent in females (35.2%). Conclusion: In conclusion, our study highlights the prevalence of common nasal deformities, emphasizing significant gender variations. These findings contribute to a deeper understanding of nasal anatomy, essential for informed decision-making in rhinoplasty.

18.
Cureus ; 15(6): e40454, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37465794

RESUMO

BACKGROUND: Chronic rhinosinusitis (CRS) is a widespread condition worldwide that is leading to a significant burden on society in terms of healthcare consumption and productivity loss. Multiple risk factors have been implicated in the pathogenesis of CRS, such as nasal allergies, bronchial asthma, smoking, nasal polyps, and immune system-related diseases. The present study aimed to assess the prevalence of CRS, the most common risk factors, and the association between diabetes, body mass index (BMI), and CRS in Saudi Arabia. METHODS: A cross-sectional study was conducted through random sampling that included 3602 participants from different regions of Saudi Arabia from November 2022 to January 2023. Electronic questionnaires were used for data collection. RESULTS: A total of 3602 individuals responded to our questionnaires; 948 (26.3%) were diagnosed by physicians as having chronic rhinosinusitis, and 75.1% were females. The majority (41.5%) were between the ages of 18 and 28 years. We found that smoking was significantly associated with sinusitis (OR 2.01, 95% CI 1.23-5.69) (p value 0.003) and that obesity was also significantly associated with sinusitis, 17.0% of persons with sinusitis were obese class I (BMI 30-35 kg/m2); 7.8% were obese class II (BMI>35 kg/m2); and 29.4% were overweight, whereas 45.8% were of normal weight. All percentages differ significantly from persons with normal weight (p value = 0.000). The most common risk factors for sinusitis were nasal allergies (44.4%), stuffy nose (22.8%), and deviation of the nasal septum (19.2%). All percentages differ significantly from persons without comorbidity (p value = 0.000). CONCLUSION: The present study showed a slight increase in the prevalence of CRS in Saudi Arabia, which is attributable to increased exposure to allergens. The most common risk factors were nasal allergies, nasal blockage, deviation of the nasal septum, and asthma. There was a significant correlation between CRS and BMI in the form of increased prevalence in overweight and obese compared to normal-weight individuals.

19.
J Pharm Bioallied Sci ; 15(Suppl 1): S554-S557, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37654340

RESUMO

Aim: To find out the prevalence of OSMF and its Co-relation of clinical grading to various habit factors (time span of habit practiced in years, repetition of habit practiced per day, time of habit practiced in minutes per use). Method: This descriptive, cross-sectional survey was carried out and close ended questionnaire was used for data collection. Demographic details like gender & age and different tissue exploiting habits like, chewing gutkha, chewing areca nut, chewing panmasala with or without tobacco, plain tobacco, mawa, smoking, alcohol was recorded. Also, duration of habit in years, repetition of habit per day, time of habit per use & site of involvement was recorded. Results: Among 5297 patients examined at OPD, 120 were diagnosed with OSMF. The present study found no statistical relation between age, gender & OSMF. The present study concluded that majority 83 (69.17%) of the OSMF patients are guthka user and buccal mucosa was most affected site. OSMF was more prevalent in patients who practiced the habit for more than 15 years. Conclusion: Among the OSMF patients, guthka was most commonly practiced & buccal mucosa was most commonly involved. Duration and frequency of consumption were significantly associated with severity of OSMF.

20.
J Neurosci ; 31(48): 17437-48, 2011 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-22131405

RESUMO

A fundamental feature of the mammalian visual system is the presence of separate channels that work in parallel to efficiently extract and analyze specific elements of a visual scene. Despite the extensive use of the mouse as a model system, it is not clear whether such parallel organization extends beyond the retina to subcortical structures, such as the dorsal lateral geniculate (dLGN) of thalamus. To begin to address this, we examined the morphology of biocytin-filled relay cells recorded in dLGN of mice. Based on a quantitative assessment of their dendritic architecture, we found that even at early postnatal ages relay cells could be readily classified as X-like (biconical), Y-like (symmetrical), or W-like (hemispheric) and that each cell type was regionally specified in dLGN. X-like cells were confined primarily to the monocular ventral region of dLGN. Y-like cells occupied a central core that also contained ipsilateral eye projections, whereas W-like cells were found along the perimeter of dLGN. Similar to cat, Y-like cells were more prevalent than X- and W-like cells, and X-like cells tended to be smaller than other cell types. However, the dendritic fields of X- and W-like cells did not exhibit an orientation bias with respect to optic tract or boundaries of dLGN. Although we found clear morphological differences among relay cells, an analysis of their electrophysiological properties did not reveal any additional distinguishing characteristics. Overall, these data coupled with recent observations in the retina suggest that the mouse has many of the hallmark features of a system-wide parallel organization.


Assuntos
Dendritos/fisiologia , Corpos Geniculados/citologia , Neurônios/citologia , Animais , Forma Celular/fisiologia , Tamanho Celular , Corpos Geniculados/fisiologia , Camundongos , Neurônios/fisiologia
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