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1.
S D Med ; 75(10): 455, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36889266

RESUMO

INTRODUCTION: Breaking bad news to patients is a daunting yet inevitable task for most physicians. When done poorly, physicians can cause further pain to the patients while creating great distress for themselves; therefore, it is important medical students learn effective and compassionate techniques. The SPIKES model was created as a guiding framework for providers to use when breaking bad news. The objective of this project was to create a sustainable method to integrate use of the SPIKES model for giving bad news to patients into the curriculum for the University of South Dakota Sanford School of Medicine (SSOM). METHODS: The changes to the curriculum occurred in three phases - one for each Pillar of the University of South Dakota SSOM's curriculum. The first session was a lecture format introducing and defining the SPIKES model for the first-year students. The second lesson was both didactic and interactive, as students were able to practice the SPIKES model through role-playing with colleagues. Prior to COVID, the final lesson was planned to be a standardized patient encounter for the graduating students; however, this lesson ended up in a virtual lecture format. A pre- and post-survey was given for each lesson to determine the usefulness of the SPIKES model in preparing students for handling these challenging conversations. RESULTS: 197 students completed the pre-test survey, and 157 students completed the post-test survey. Overall, a statistically significant improvement was found in students' self-reported confidence, preparedness, and comfort. When the data was broken down based upon year of training, not all cohorts had statistically significant improvement in all three categories. CONCLUSIONS: The SPIKES model serves as a good framework for students to use and tailor to the specific patient encounters. It was evident these lessons greatly improved the student's confidence, comfort, and plan of action. The next step would be to study whether improvement is noted from a patient's perspective and what mode of instruction was most effective.


Assuntos
COVID-19 , Estudantes de Medicina , Humanos , Relações Médico-Paciente , Revelação da Verdade , Faculdades de Medicina , Currículo , Comunicação
2.
S D Med ; 75(8): 364-368, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36745985

RESUMO

BACKGROUND: In 2011, the AAP endorsed the recommendation of National Heart Lung and Blood Institute (NHLBI) for universal lipid screening in children 9-11 and 17-21 years old given the increasing prevalence of pediatric obesity. In 2017, a study conducted by the AAP showed low adherence with universal pediatric lipid screening. The purpose of this retrospective chart review is to assess the adherence rate for pediatric lipid screening at a rural, independently owned primary care and multispecialty clinic. METHODS: Patient data were compiled from the electronic medical record. Inclusion criteria include patients 9-11 or 17-21 years of age between Jan. 1, 2014-Dec. 31, 2019, with an appointment indication of well-child examination or annual physical. RESULTS: A low percentage of patients underwent a fasting lipid panel in both the 9-11 (n = 663) and 17-21 (n = 118) years age group, 3.3 percent and 4.2 percent respectively. Of those who underwent a fasting lipid panel, 59.0 percent in the 9-11 age group and 80.0 percent in the 17-21 years age group had at least one abnormal lipid level. Of the population classified as overweight and obese, 6.3 percent (16 out of 255) of the 9-11 years age group and 6.1 percent (three out of 49) of the 17-21 years age group underwent a lipid panel screen. DISCUSSION: The data show low adherence with universal lipid screening for patients ages 9-11 and 17-21 years old. Poor adherence may be due to inconsistent endorsement by professional medical societies and incongruent recommendations in the EMR. Further studies are required to determine the national adherence rate with the NHLBI recommendation.


Assuntos
Sobrepeso , Obesidade Infantil , Humanos , Criança , Adolescente , Adulto Jovem , Adulto , Estudos Retrospectivos , Obesidade Infantil/diagnóstico , Obesidade Infantil/epidemiologia , Obesidade Infantil/prevenção & controle , Programas de Rastreamento , Atenção Primária à Saúde , Lipídeos
3.
Pediatr Crit Care Med ; 20(10): e473-e479, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31232856

RESUMO

OBJECTIVES: To assess the relationship between quantitative and perceived cardiopulmonary resuscitation performance when healthcare providers have access to and familiarity with audiovisual feedback devices. DESIGN: Prospective observational study. SETTING: In situ simulation events throughout a pediatric quaternary care center where the use of continuous audiovisual feedback devices during cardiopulmonary resuscitation is standard. SUBJECTS: Healthcare providers who serve as first responders to in-hospital cardiopulmonary arrest. INTERVENTIONS: High-fidelity simulation of resuscitation with continuous audiovisual feedback. MEASUREMENTS AND MAIN RESULTS: Objective data was collected using accelerometer-based measurements from a cardiopulmonary resuscitation defibrillator/monitor. After the simulation event but before any debriefing, participants completed self-evaluation forms to assess whether they believed the cardiopulmonary resuscitation performed met the American Heart Association guidelines for chest compression rate, chest compression depth, chest compression fraction, chest compression in target, and duration of preshock pause and postshock pause. An association coefficient (kappa) was calculated to determine degree of agreement between perceived performance and the quantitative performance data that was collected from the CPR defibrillator/monitor. Data from 27 mock codes and 236 participants was analyzed. Average cardiopulmonary resuscitation performance was chest compression rate 106 ± 10 compressions per minute; chest compression depth 2.05 ± 0.6 in; chest compression fraction 74% ± 10%; chest compression in target 22% ± 21%; preshock pause 8.6 ± 7.2 seconds; and postshock pause 6.4 ± 8.9 seconds. When all healthcare providers were analyzed, the association coefficient (κ) for chest compression rate (κ = 0.078), chest compression depth (κ = 0.092), chest compression fraction (κ = 0.004), preshock pause (κ = 0.321), and postshock pause (κ = 0.40) was low, with no variable achieving moderate agreement (κ > 0.4). CONCLUSIONS: Cardiopulmonary resuscitation performance during mock codes does not meet the American Heart Association's quality recommendations. Healthcare providers have poor insight into the quality of cardiopulmonary resuscitation during mock codes despite access to and familiarity with continuous audiovisual feedback.


Assuntos
Atitude do Pessoal de Saúde , Reanimação Cardiopulmonar/normas , Parada Cardíaca/terapia , Treinamento por Simulação/métodos , Recursos Audiovisuais , Reanimação Cardiopulmonar/psicologia , Feedback Formativo , Fidelidade a Diretrizes , Pessoal de Saúde/psicologia , Pessoal de Saúde/normas , Hospitais Pediátricos , Humanos , Guias de Prática Clínica como Assunto , Estudos Prospectivos
4.
Appl Environ Microbiol ; 84(8)2018 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-29427422

RESUMO

Candida is a member of the normal human microbiota and often resides on mucosal surfaces such as the oral cavity or the gastrointestinal tract. In addition to their commensality, Candida species can opportunistically become pathogenic if the host microbiota is disrupted or if the host immune system becomes compromised. An important factor for Candida pathogenesis is its ability to form biofilm communities. The two most medically important species-Candida albicans and Candida glabrata-are often coisolated from infection sites, suggesting the importance of Candida coculture biofilms. In this work, we report that biofilm formation of the coculture population depends on the relative ratio of starting cell concentrations of C. albicans and C. glabrata When using a starting ratio of C. albicans to C. glabrata of 1:3, ∼6.5- and ∼2.5-fold increases in biofilm biomass were observed relative to those of a C. albicans monoculture and a C. albicans/C. glabrata ratio of 1:1, respectively. Confocal microscopy analysis revealed the heterogeneity and complex structures composed of long C. albicans hyphae and C. glabrata cell clusters in the coculture biofilms, and reverse transcription-quantitative PCR (qRT-PCR) studies showed increases in the relative expression of the HWP1 and ALS3 adhesion genes in the C. albicans/C. glabrata 1:3 biofilm compared to that in the C. albicans monoculture biofilm. Additionally, only the 1:3 C. albicans/C. glabrata biofilm demonstrated an increased resistance to the antifungal drug caspofungin. Overall, the results suggest that interspecific interactions between these two fungal pathogens increase biofilm formation and virulence-related gene expression in a coculture composition-dependent manner.IMPORTANCECandida albicans and Candida glabrata are often coisolated during infection, and the occurrence of coisolation increases with increasing inflammation, suggesting possible synergistic interactions between the two Candida species in pathogenesis. During the course of an infection, the prevalence of each Candida species may change over time due to differences in metabolism and in the resistance of each species to antifungal therapies. Therefore, it is necessary to understand the dynamics between C. albicans and C. glabrata in coculture to develop better therapeutic strategies against Candida infections. Existing in vitro work has focused on understanding how an equal-part culture of C. albicans and C. glabrata impacts biofilm formation and pathogenesis. What is not understood, and what is investigated in this work, is how the composition of Candida species in coculture impacts overall biofilm formation, virulence gene expression, and the therapeutic treatment of biofilms.


Assuntos
Antifúngicos/farmacologia , Biofilmes , Candida albicans/fisiologia , Candida glabrata/fisiologia , Técnicas de Cocultura , Biofilmes/crescimento & desenvolvimento , Candida albicans/patogenicidade , Candida glabrata/patogenicidade , Expressão Gênica/fisiologia , Genes Fúngicos/fisiologia , Testes de Sensibilidade Microbiana , Virulência/genética
5.
J Pediatr Hematol Oncol ; 38(1): 17-21, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26491854

RESUMO

Diastolic dysfunction has been shown to occur earlier than systolic dysfunction in iron overload states in adult patients with sickle cell disease (SCD). Tissue Doppler imaging (TDI)-derived E/E' has emerged as a noninvasive marker of diastolic function. We sought to determine diastolic function in children with SCD and study its relation with iron overload. A retrospective review of medical records of 225 pediatric patients with SCD who received an echocardiogram between January 2008 and December 2012 was performed. Echocardiographic measures including M-mode, spectral Doppler, and TDI-derived E/E' were compared with previously published data in healthy children. The left ventricular end-diastolic and end-systolic dimensions were significantly higher in SCD (P<0.0001) and the shortening fraction was similar (P=0.66). E/E' ratio was significantly higher in SCD at the mitral annulus, septum, and tricuspid annulus. In 54% of subjects, the septal E/E' was >8, indicating elevated left ventricular filling pressure. However, there was no significant correlation between ferritin level and E/E' ratios. Pediatric patients with SCD have a high prevalence of elevated estimated left ventricular filling pressure, but this does not correlate with ferritin levels.


Assuntos
Anemia Falciforme/complicações , Ferritinas/sangue , Sobrecarga de Ferro/complicações , Disfunção Ventricular Esquerda/diagnóstico por imagem , Adolescente , Anemia Falciforme/sangue , Anemia Falciforme/diagnóstico por imagem , Criança , Diástole , Ecocardiografia Doppler , Feminino , Humanos , Sobrecarga de Ferro/sangue , Sobrecarga de Ferro/diagnóstico por imagem , Masculino , Estudos Retrospectivos , Disfunção Ventricular Esquerda/etiologia
6.
J Ind Microbiol Biotechnol ; 43(10): 1355-63, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27423881

RESUMO

An evolutionary engineering approach for enhancing heterologous carotenoids production in an engineered Saccharomyces cerevisiae strain was used previously to isolate several carotenoids hyper-producers from the evolved populations. ß-Carotene production was characterized in the parental and one of the evolved carotenoids hyper-producers (SM14) using bench-top bioreactors to assess the impact of pH, aeration, and media composition on ß-carotene production levels. The results show that with maintaining a low pH and increasing the carbon-to-nitrogen ratio (C:N) from 8.8 to 50 in standard YNB medium, a higher ß-carotene production level at 25.52 ± 2.15 mg ß-carotene g(-1) (dry cell weight) in the carotenoids hyper-producer was obtained. The increase in C:N ratio also significantly increased carotenoids production in the parental strain by 298 % [from 5.68 ± 1.24 to 22.58 ± 0.11 mg ß-carotene g(-1) (dcw)]. In this study, it was shown that Raman spectroscopy is capable of monitoring ß-carotene production in these cultures. Raman spectroscopy is adaptable to large-scale fermentations and can give results in near real-time. Furthermore, we found that Raman spectroscopy was also able to measure the relative lipid compositions and protein content of the parental and SM14 strains at two different C:N ratios in the bioreactor. The Raman analysis showed a higher total fatty acid content in the SM14 compared with the parental strain and that an increased C:N ratio resulted in significant increase in total fatty acid content of both strains. The data suggest a positive correlation between the yield of ß-carotene per biomass and total fatty acid content of the cell.


Assuntos
Reatores Biológicos , Saccharomyces cerevisiae/metabolismo , Análise Espectral Raman , beta Caroteno/biossíntese , Biomassa , Fermentação , Nitrogênio/metabolismo
7.
Appl Environ Microbiol ; 80(12): 3729-40, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24727267

RESUMO

Biocatalyst robustness toward stresses imposed during fermentation is important for efficient bio-based production. Osmotic stress, imposed by high osmolyte concentrations or dense populations, can significantly impact growth and productivity. In order to better understand the osmotic stress tolerance phenotype, we evolved sexual (capable of in situ DNA exchange) and asexual Escherichia coli strains under sodium chloride (NaCl) stress. All isolates had significantly improved growth under selection and could grow in up to 0.80 M (47 g/liter) NaCl, a concentration that completely inhibits the growth of the unevolved parental strains. Whole genome resequencing revealed frequent mutations in genes controlling N-acetylglucosamine catabolism (nagC, nagA), cell shape (mrdA, mreB), osmoprotectant uptake (proV), and motility (fimA). Possible epistatic interactions between nagC, nagA, fimA, and proV deletions were also detected when reconstructed as defined mutations. Biofilm formation under osmotic stress was found to be decreased in most mutant isolates, coupled with perturbations in indole secretion. Transcriptional analysis also revealed significant changes in ompACGL porin expression and increased transcription of sulfonate uptake systems in the evolved mutants. These findings expand our current knowledge of the osmotic stress phenotype and will be useful for the rational engineering of osmotic tolerance into industrial strains in the future.


Assuntos
Acetilglucosamina/metabolismo , Proteínas de Escherichia coli/genética , Escherichia coli/citologia , Escherichia coli/metabolismo , Pressão Osmótica , Mutação Puntual , Escherichia coli/química , Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Cloreto de Sódio/metabolismo
8.
J Cardiol ; 83(3): 184-190, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37684005

RESUMO

BACKGROUND: As the catheter-based device closure of the patent foramen ovale (PFO) is expanding, novel devices aim to address the limitations of first-generation occluders (e.g. bulk, erosion, dislodgment). The second-generation device from Encore Medical (Eagan, MN, USA) features an articulating frame structure which allows the device to better conform to atrial anatomies, has lower disc thickness and metal mass/surface area, and is fully retrievable at any point in the procedure. The aim of the study was to evaluate the feasibility and safety of a novel low-profile, fully retrievable, Encore PFO closure device in the animal model. METHODS: Six swine underwent implantation of the novel PFO occluder under fluoroscopic and intra-cardiac echocardiography guidance and survived for 140 days. Interim transthoracic echocardiography (TTE) was conducted on Day 29. Following terminal angiography and TTE at 140 days, the hearts were subjected to gross and histopathologic analysis. RESULTS: All animals were successfully implanted and survived for 140 days. Interim TTE revealed proper device retention with no blood flow across the septum or thrombus in any of the animals. X-ray and pathology results showed preserved implant integrity with no fractures, and complete integration of the devices into the septum with complete re-endothelialization and nearly complete coverage by a mature, relatively thin neoendocardium. No surface fibrin deposition or thrombosis was reported. CONCLUSIONS: In the standard porcine model, device retention and biocompatibility remained favorable following structural and functional device modifications exemplified by the second-generation PFO occluder from Encore Medical, including marked reduction of metal mass.


Assuntos
Forame Oval Patente , Dispositivo para Oclusão Septal , Suínos , Animais , Resultado do Tratamento , Cateterismo Cardíaco/métodos , Ecocardiografia , Forame Oval Patente/diagnóstico por imagem , Forame Oval Patente/cirurgia , Fluoroscopia
10.
Crit Care Clin ; 19(1): 127-49, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12688581

RESUMO

The critical care aspects of obstetrics and pregnancy are varied and demand that critical care practitioners have a thorough knowledge of fetal and maternal changes in physiology as pregnancy progresses. Pregnancy can affect every organ system; and organ-specific conditions as well as syndromes that span multiple organ systems were described. Care of the critically ill, pregnant patient requires a true multidisciplinary approach for optimal outcomes. A review of the current concepts and suggestions for therapy were presented.


Assuntos
Complicações na Gravidez/terapia , Adulto , Doenças Autoimunes/fisiopatologia , Cuidados Críticos , Fenômenos Fisiológicos do Sistema Digestório , Eclampsia/fisiopatologia , Eclampsia/terapia , Desenvolvimento Embrionário e Fetal/fisiologia , Feminino , Síndrome HELLP/fisiopatologia , Síndrome HELLP/terapia , Hemodinâmica , Humanos , Incidência , Rim/fisiologia , Pré-Eclâmpsia/fisiopatologia , Pré-Eclâmpsia/terapia , Gravidez , Complicações na Gravidez/epidemiologia , Complicações Cardiovasculares na Gravidez/fisiopatologia , Prevalência , Doenças Respiratórias/fisiopatologia , Doenças Respiratórias/terapia , Procedimentos Cirúrgicos Operatórios , Ferimentos e Lesões
11.
J Voice ; 16(1): 52-60, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12002887

RESUMO

Aerobic instructors frequently experience vocal fatigue and are at risk for the development of vocal fold pathology. Six female aerobic instructors, three with self-reported voice problems and three without, served as subjects. Measures of vocal function (perturbation and EGG) were obtained before and after a 30-minute exercise session. Results showed that the group with self-reported voice problems had greater amounts of jitter, lower harmonic-to-noise ratios, and less periodicity in sustained vowels overall, but no significant differences in measures of perturbation and EGG were found before and immediately after instruction. Measures of vocal parameters showed that subjects with self-reported voice problems projected with relatively greater vocal intensity and phonated for a greater percentage of time across beginning, middle, and ending periods of aerobic instruction than subjects with no reported voice problems.


Assuntos
Exercício Físico , Ensino , Distúrbios da Voz/diagnóstico , Qualidade da Voz , Adulto , Eletromiografia/métodos , Feminino , Glote/fisiologia , Humanos , Fonética , Reprodutibilidade dos Testes , Acústica da Fala , Distúrbios da Voz/epidemiologia
12.
Pediatr Dev Pathol ; 17(4): 250-64, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24735181

RESUMO

Heterotaxy is a rare disease with high morbidity and mortality. Controversy exists over how to classify these syndromes with most cases stratified into asplenia/polysplenia syndromes or right/left isomerism. In an effort to review comprehensively specific pheonotypes associated with heterotaxy syndromes, we reviewed published cases series, adopted a classification scheme based on spleen status, and evaluated autopsy cases retrospectively with abnormal laterality at our institution. We categorized 116 cases as situs inversus totalis, polysplenia, asplenia, and single right-sided spleen. Cardiovascular abnormalities occurred in 87.1% of polysplenia, 90.5% of asplenia, and all cases of single right-sided spleen. For polysplenia, 48.9% had bilateral bilobed lungs, 87% had right-sided stomach, 58.1% had midline symmetric liver, and 60.4% had malrotated intestines. For asplenia, 51.9% had bilateral trilobed lungs, 86.7% had right-sided stomach, 45.8% had symmetric liver, and 65.5% had malrotated intestines. Atrioventricular septal defects occurred in 91.2% of asplenia compared to 56.8% of polysplenia cases. Eight percent had pulmonary/aortic stenosis or atresia. Double outlet right ventricle was more common in polysplenia (32.6%) compared to asplenia (21.4%). Total anomalous systemic venous return was described in 55.6% of polysplenia and total anomalous pulmonary venous connections in 81% of asplenia cases. Greater than half of the cases had no heterotaxy diagnosis. Although, we found similar heterotaxy-associated characteristics, the frequencies differed from previous studies. We found great variation in how heterotaxy-associated defects were described, diagnosed, and reported. Although there are known associated characteristics with the polysplenia/asplenia syndromes, correct identification requires a standardized approach for diagnosis and reporting.


Assuntos
Cardiopatias Congênitas/patologia , Síndrome de Heterotaxia/patologia , Intestinos/anormalidades , Fígado/anormalidades , Pulmão/anormalidades , Situs Inversus/patologia , Baço/anormalidades , Estômago/anormalidades , Adolescente , Autopsia , Baltimore , Criança , Pré-Escolar , Feminino , Predisposição Genética para Doença , Cardiopatias Congênitas/genética , Cardiopatias Congênitas/mortalidade , Síndrome de Heterotaxia/genética , Síndrome de Heterotaxia/mortalidade , Humanos , Lactente , Recém-Nascido , Masculino , Fenótipo , Prognóstico , Estudos Retrospectivos , Situs Inversus/genética , Situs Inversus/mortalidade
13.
Am J Surg ; 207(3): 387-92; discussion 391-2, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24581763

RESUMO

BACKGROUND: Obesity's effect on the outcomes of trauma patients remains inconclusive. METHODS: A retrospective review of all falls, motor vehicle collisions (MVCs), and penetrating trauma patients admitted from January 2008 to December 2012 was performed. The outcomes evaluated included mortality, length of stay at hospital, and discharge disposition. Patients were grouped according to the body mass index (BMI) and stratified by injury severity scores. RESULTS: Two thousand one hundred ninety six patients were analyzed; 132 penetrating, 913 falls, and 1,151 MVCs. Penetrating traumas had no significant difference in outcomes. In falls, obese patients had a lower mortality (P = .035). In MVCs, obese patients had longer hospitalizations (P = .02), and mild and moderate MVC injuries were less likely to be discharged home (P = .032 and .003). Obese patients sustained fewer head injuries in falls and MVCs (P = .005 and .043, respectively). CONCLUSIONS: In falls, a higher BMI may benefit patients. However, an increasing BMI is associated with a longer length of stay at hospital, and decreased likelihood of discharge to home.


Assuntos
Acidentes por Quedas/estatística & dados numéricos , Acidentes de Trânsito/estatística & dados numéricos , Obesidade/complicações , Ferimentos Penetrantes/epidemiologia , Índice de Massa Corporal , Comorbidade , Humanos , Illinois/epidemiologia , Escala de Gravidade do Ferimento , Tempo de Internação , Obesidade/epidemiologia , Avaliação de Resultados em Cuidados de Saúde , Alta do Paciente/estatística & dados numéricos , Sistema de Registros , Estudos Retrospectivos , Ferimentos e Lesões/epidemiologia
14.
Crit Care Clin ; 26(4): 665-8, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20970054

RESUMO

Performance of procedures upon the obese critically ill patient in the ICU or in the radiology suite, require certain considerations. Additional staff, equipment and proper ergonomics are often necessary to perform these procedures safely for both patient and staff.


Assuntos
Obesidade , Quartos de Pacientes , Radiologia , Cuidados Críticos , Drenagem/instrumentação , Drenagem/métodos , Gastrostomia/métodos , Humanos , Proctoscopia , Sigmoidoscopia
16.
J Comp Neurol ; 515(5): 548-64, 2009 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-19479997

RESUMO

In rats, whisking behavior is characterized by high-frequency synchronous movements and other stereotyped patterns of bilateral coordination that are rarely seen in the bilateral movements of the limbs. This suggests that the motor systems controlling whisker and limb movements must have qualitative or quantitative differences in their interhemispheric connections. To test this hypothesis, anterograde tracing methods were used to characterize the bilateral distribution of projections from the whisker and forepaw regions in the primary motor (MI) cortex. Unilateral tracer injections in the MI whisker or forepaw regions revealed robust projections to the corresponding MI cortical area in the contralateral hemisphere. Both MI regions project bilaterally to the neostriatum, but the corticostriatal projections from the whisker region are denser and more evenly distributed across both hemispheres than those from the MI forepaw region. The MI whisker region projects bilaterally to several nuclei in the thalamus, whereas the MI forepaw region projects almost exclusively to the ipsilateral thalamus. The MI whisker region sends dense projections to the contralateral claustrum, but those to the ipsilateral claustrum are less numerous. By contrast, the MI forepaw region sends few projections to the claustrum of either hemisphere. Bilateral deposits of different tracers in MI revealed overlapping projections to the neostriatum, thalamus, and claustrum when the whisker regions were injected, but not when the forepaw regions were injected. These results suggest that the bilateral coordination of the whiskers depends, in part, on MI projections to the contralateral neostriatum, thalamus, and claustrum.


Assuntos
Gânglios da Base/anatomia & histologia , Comportamento Exploratório/fisiologia , Córtex Motor/anatomia & histologia , Neostriado/anatomia & histologia , Vias Neurais , Tálamo/anatomia & histologia , Vibrissas/inervação , Animais , Comportamento Animal/fisiologia , Mapeamento Encefálico/métodos , Masculino , Vias Neurais/anatomia & histologia , Vias Neurais/fisiologia , Prosencéfalo/anatomia & histologia , Ratos , Ratos Sprague-Dawley
17.
J Comp Neurol ; 510(1): 100-16, 2008 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-18615539

RESUMO

Rat whisking behavior is characterized by high amounts of bilateral coordination in which whisker movements on both sides of the face are linked. To elucidate the neural substrate that might mediate this bilateral coordination, neuronal tracers were used to characterize the bilateral distribution of corticothalamic projections from primary motor (MI) cortex. Some rats received tracers in the MI whisker region, whereas others received tracers in the MI forepaw region. The MI whisker region projects bilaterally to the anteromedial (AM), ventromedial (VM), and ventrolateral (VL) nuclei, and to parts of the intralaminar nuclei. By contrast, the MI forepaw region sends virtually no projections to the contralateral thalamus. Consistent with these findings, bilateral injections of different tracers into the MI whisker region of each hemisphere produced tracer overlap on both sides of the thalamus. Furthermore, MI whisker projections to the contralateral thalamus terminate in close proximity to the thalamocortical neurons that project to the MI whisker region of that contralateral hemisphere. The terminal endings of the contralateral corticothalamic projections contain small synaptic varicosities and other features that resemble the modulator pathways described for other corticothalamic projection systems. In addition, tracer injections into AM, VM, and VL revealed dense clusters of labeled neurons in layer VI of the medial agranular (Agm) zone, which corresponds to the MI whisker region. These results suggest that projections from the MI whisker region to the contralateral thalamus may modulate the callosal interactions that are presumed to play a role in coordinating bilateral whisking behavior.


Assuntos
Córtex Cerebral/fisiologia , Cérebro/fisiologia , Córtex Motor/fisiologia , Ratos , Transmissão Sináptica/fisiologia , Tálamo/fisiologia , Vibrissas/fisiologia , Animais , Membro Anterior/fisiologia , Lateralidade Funcional/fisiologia , Masculino , Movimento/fisiologia , Terminações Nervosas/ultraestrutura , Vias Neurais/fisiologia , Vias Neurais/ultraestrutura , Ratos Sprague-Dawley
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