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1.
J Urol ; 210(5): 778-781, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37675864

RESUMO

PURPOSE: Up to 90% of men with a positive surgical margin show remaining cancer in subsequent reresections. The risk of local recurrence in men with no penile cancer but the precancerous lesion penile intraepithelial neoplasia at the surgical margin is less well studied and was the aim of this analysis. MATERIAL AND METHODS: This was a retrospective analysis of men with distal penile cancer undergoing penile-sparing surgery. A competing risks survival analysis adjusted for grade, lymphovascular invasion, and stage was performed to assess local recurrence-free survival in patients with penile intraepithelial neoplasia-positive margins and completely negative surgical margins. RESULTS: A negative surgical margin was described in 319 men (85%), whereas penile intraepithelial neoplasia in the surgical margin was found in 59 men (15%). Local recurrence was observed in 30/319 men with a negative surgical margin compared to 11/59 men with penile intraepithelial neoplasia in the surgical margin. Adjusted for T stage and grade, patients with penile intraepithelial neoplasia at the surgical margin had a higher risk to develop a local recurrence than those with a negative surgical margin without penile intraepithelial neoplasia (HR 1.51, 95% CI 1.07-2.12, P = .019). CONCLUSIONS: Men with a penile intraepithelial neoplasia-positive surgical margin have an increased risk to experience local recurrence compared to men with a negative surgical margin and should undergo closer surveillance and/or adjuvant treatment.

2.
World J Urol ; 41(6): 1581-1588, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37019998

RESUMO

PURPOSE: To describe our surgical technique and report the oncological outcomes and complication rates using a fascial-sparing radical inguinal lymphadenectomy (RILND) technique for penile cancer patients with cN+ disease in the inguinal lymph nodes. METHODS: Over a 10-year period, 660 fascial-sparing RILND procedures were performed in 421 patients across two specialist penile cancer centres. The technique used a subinguinal incision with an ellipse of skin excised over any palpable nodes. Identification and preservation of the Scarpa's and Camper's fascia was the first step. All superficial inguinal nodes were removed en bloc under this fascial layer with preservation of the subcutaneous veins and fascia lata. The saphenous vein was spared where possible. Patient characteristics, oncologic outcomes and perioperative morbidity were retrospectively collected and analysed. Kaplan-Meier curves estimated the cancer-specific survival (CSS) functions after the procedure. RESULTS: Median (interquartile range, IQR) follow-up was 28 (14-90) months. A median (IQR) number of 8.0 (6.5-10.5) nodes were removed per groin. A total of 153 postoperative complications (36.1%) occurred, including 50 conservatively managed wound infections (11.9%), 21 cases of deep wound dehiscence (5.0%), 104 cases of lymphoedema (24.7%), 3 cases of deep vein thrombosis (0.7%), 1 case of pulmonary embolism (0.2%), and 1 case of postoperative sepsis (0.2%). The 3-year CSS was 86% (95%Confidence Interval [95% CI] 77-96), 83% (95% CI 72-92), 58% (95% CI 51-66), respectively, for the pN1, pN2 and pN3 patients (p < 0.001), compared to a 3-year CSS of 87% (95% CI 84-95) for the pN0 patients. CONCLUSION: Fascial-sparing RILND offers excellent oncological outcomes whilst decreasing the morbidity rates. Patients with more advanced nodal involvement had poorer survival rates, emphasizing the need for adjuvant chemo-radiotherapy.


Assuntos
Neoplasias Penianas , Masculino , Humanos , Neoplasias Penianas/cirurgia , Neoplasias Penianas/patologia , Estudos Retrospectivos , Complicações Pós-Operatórias/etiologia , Excisão de Linfonodo/métodos , Veia Safena/patologia , Veia Safena/cirurgia , Fáscia , Canal Inguinal/patologia , Canal Inguinal/cirurgia
3.
J Neurosci ; 38(29): 6427-6438, 2018 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-29921715

RESUMO

The BRAIN Initiative arose from a grand challenge to "accelerate the development and application of new technologies that will enable researchers to produce dynamic pictures of the brain that show how individual brain cells and complex neural circuits interact at the speed of thought." The BRAIN Initiative is a public-private effort focused on the development and use of powerful tools for acquiring fundamental insights about how information processing occurs in the central nervous system (CNS). As the Initiative enters its fifth year, NIH has supported >500 principal investigators, who have answered the Initiative's challenge via hundreds of publications describing novel tools, methods, and discoveries that address the Initiative's seven scientific priorities. We describe scientific advances produced by individual laboratories, multi-investigator teams, and entire consortia that, over the coming decades, will produce more comprehensive and dynamic maps of the brain, deepen our understanding of how circuit activity can produce a rich tapestry of behaviors, and lay the foundation for understanding how its circuitry is disrupted in brain disorders. Much more work remains to bring this vision to fruition, and the National Institutes of Health continues to look to the diverse scientific community, from mathematics, to physics, chemistry, engineering, neuroethics, and neuroscience, to ensure that the greatest scientific benefit arises from this unique research Initiative.


Assuntos
Mapeamento Encefálico/métodos , Neurociências/métodos , Animais , Humanos , National Institutes of Health (U.S.) , Estados Unidos
4.
J Shoulder Elbow Surg ; 28(10): 2031-2038, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31350107

RESUMO

BACKGROUND: To date, no gold-standard technique exists for the treatment of chronic acromioclavicular joint (ACJ) instability. We systematically reviewed the clinical results of 3 main categories of ACJ reconstruction for high-grade chronic instability. METHODS: A literature search was performed according to Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. The inclusion criteria were clinical studies involving patients with ACJ instability (Rockwood grades III-VI) for at least 6 weeks, managed with ACJ stabilization, with a minimum 1-year follow-up. Depending on the surgical technique, patients were divided into 1 of 3 groups: nonbiological fixation between the coracoid and clavicle, for example, suture loops and synthetic ligaments (group 1); biological reconstruction of the coracoclavicular ligaments, for example, allograft or autograft ligament reconstruction (group 2); and ligament and/or tendon transfer, for example, the Weaver-Dunn procedure (group 3). Patient demographic characteristics, functional scores, radiographic outcomes, and complications were compared. RESULTS: Two independent investigators reviewed 960 articles. A total of 27 studies met the inclusion criteria, comprising 590 patients divided into 1 of 3 groups. The complication rates were similar among the 3 groups: 15% for nonbiological fixation, 15% for biological reconstruction, and 17% for ligament and/or tendon transfer, with failure rates of 8%, 7%, and 5%, respectively. In terms of functional results, the mean Constant score was 87.2 points for nonbiological fixation (n = 89), 92.4 points for biological reconstruction (n = 86), and 87.4 points for ligament and/or tendon transfer (n = 49). CONCLUSION: On comparison of the results of 3 different ACJ reconstruction methods, all techniques showed similar complication rates. Among the level II studies, ACJ reconstruction with a tendon graft showed superior results.


Assuntos
Articulação Acromioclavicular/cirurgia , Artroplastia/métodos , Luxações Articulares/cirurgia , Instabilidade Articular/cirurgia , Articulação Acromioclavicular/fisiopatologia , Artroplastia/efeitos adversos , Doença Crônica , Humanos , Ligamentos Articulares/transplante , Procedimentos de Cirurgia Plástica/métodos , Técnicas de Sutura , Suturas , Transferência Tendinosa
5.
Intern Med J ; 47(4): 394-399, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28401723

RESUMO

There has been a decline in the proportion of clinical academics compared with full-time clinicians, since 2004. A Working Party was established to help develop and implement a model for the training of clinical academics. After a highly successful first summit in 2014 that summarised the challenges faced by clinical academics in Australia and New Zealand, a second summit was convened late in 2015 to report on progress and to identify key areas for further action. The second summit provided survey results that identified the varied training pathways currently offered to clinical academics and the institutions willing to be involved in developing improved pathways. A literature review also described the contributions that clinical academics make to the health sector and the challenges faced by this workforce sector. Current training pathways created for clinical academics by Australasian institutions were presented as examples of what can be done. The perspectives of government and research organisations presented at the summit helped define how key stakeholders can contribute. Following the summit, there was a strong commitment to continue to work towards developing a sustainable and defined training pathway for clinical academics. The need for a coordinated and integrated approach was highlighted. Some key objectives were agreed upon for the next phase, including identifying and engaging key advocates within government and leading institutions; publishing and profiling the contributions of successful clinical academics to healthcare outcomes; defining the stages of a clinical academic training pathway; and establishing a mentoring programme for training clinical academics.


Assuntos
Competência Clínica/normas , Educação de Pós-Graduação em Medicina , Docentes de Medicina/organização & administração , Internato e Residência , Acreditação , Austrália , Necessidades e Demandas de Serviços de Saúde , Humanos , Satisfação no Emprego , Liderança , Nova Zelândia , Avaliação de Programas e Projetos de Saúde , Pesquisa Qualitativa
7.
ANZ J Surg ; 94(7-8): 1221-1227, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39016334

RESUMO

The Supervisor Support Consensus Statement has been developed after consultation with supervisors of surgical training for the Royal Australasian College of Surgeons (RACS) programmes in Australia and Aotearoa New Zealand and other key stakeholders. Six key areas have been recognized with specific recommendations crafted to improve the support and recognition of Supervisors: 1. Clarity of role, 2. Education and Training, 3. Local support, 4. RACS support, 5. Recognition and valuing of the Supervisor role, 6. Risk Management. The purpose of this consensus statement is to clearly articulate supervisor opinions on the support they require to undertake this important role. It has been produced by an independent writing group of experienced surgical supervisors and educators, with support from RACS education department. The consensus statement is a response to a needs assessment of supervisors of surgical training. The statements in this consensus document have been generated from comments and feedback from supervisors that have been refined through process of extensive consultation using a Delphi methodology. We advise specialty training Committees consider these statements and mandate them as part of their accreditation of terms. The role of the supervisor of training requires greater recognition, and incorporation in the Enterprise Bargaining Agreement (EBA) in Australia and the ASMS Te Whatu Ora SECA in Aotearoa New Zealand would ensure the provisions in this document are enacted. The six areas identified have transferability to other specialities and countries and are valuable when considering how to support supervisors involved in training our next generation of specialist doctors.


Assuntos
Consenso , Austrália , Nova Zelândia , Humanos , Cirurgia Geral/educação , Cirurgiões/educação , Educação de Pós-Graduação em Medicina/métodos
8.
Clin Genitourin Cancer ; : 102168, 2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-39117530

RESUMO

BACKGROUND: Penile cancer (PeCa) is a rare cancer with surgical options that affect patients' quality-of-life. Patient-reported outcome measures (PROMs) are uncommonly utilized in this cohort despite their several patient-centered benefits and there are recommendations to further digitalize PROMs. This prospective, population-based study aimed to report the development and feasibility of a novel electronic patient-reported outcome measures (ePROMs) questionnaire for patients with PeCa. MATERIALS AND METHODS: A novel ePROMs questionnaire was developed and sent to patients 3 days before outpatient clinic appointments. The questionnaire included up to 30 items on patient symptomology and quality-of-life, including a self-reported quality-of-life score (rated 0 being worst and 100 being best). Data were collected for patients followed up between August 2021 and May 2022. The primary feasibility outcomes, adherence and engagement, were measured by response and drop-out rates. Differences in responders and nonresponders were also ascertained. Secondary outcomes explored the clinical utility of the questionnaire. Responders were subcategorized into 3 groups: circumcision (Ci), partial penectomy (PP) or total penectomy (TP) and differences were analyzed. This study was approved by the local Trust Governance Panel, including for ethical considerations. RESULTS: 220 adult males were sent ePROMs questionnaires, and 141 (64%) responded initially. The mean dropout rate of subsequent questionnaires was 56%. The maximum number of questionnaires sent to and completed by a patient was 8 (n = 1). Nonresponders were older (P < .0001), with poorer performance status (P < .0001) and lower body mass index (P = .0288). TP patients reported the lowest median quality-of-life score 68.50 (8-99), followed by the Ci group (72.0, 37-94) and the PP group (76.0, 10-99). CONCLUSIONS: Patients initially engaged and adhered to the ePROMs questionnaire but struggled to maintain this over time. Clinical data gathered by the questionnaire may be utilized to inform patient care. The questionnaire requires additional validation, research, and education.

9.
Eur Urol Oncol ; 2023 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-37813746

RESUMO

BACKGROUND: Penile squamous cell carcinoma (PSCC) is characterised by stepwise lymphatic dissemination. Skip metastases (SkMs) are rare metastases in the corpus cavernosum or spongiosum without continuity to the primary tumour or its resection site. OBJECTIVE: To assess the distinct pattern of spread in SkM+ patients and the effect of SkM on prognosis. DESIGN, SETTING, AND PARTICIPANTS: We conducted a retrospective analysis of patients with SkM+ PSCC at ten high-volume international referral centres between January 2006 and May 2022. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: We evaluated histopathological data, primary lymph node (LN) staging, and metastatic spread. We included a cohort of patients matched for pT stage, LN status, and grade who did not have SkM (SkM-) to compare the SkM prognosis and predictive value for cancer-specific mortality (CSM). RESULTS AND LIMITATIONS: Among the 63 SkM+ patients who met our inclusion criteria, the SkM diagnosis was synchronous in 54.0% and metastases were mostly located in the corpus cavernosum. SkM was symptomatic in 14% of cases, was detected on imaging in 32%, and was found incidentally on pathological examination in 27%. Fifty-one patients (81%) presented with positive LNs and 28 (44%) developed distant metastases. Seven patients (11%) presented with or developed distant metastasis without displaying any LN involvement. The 2-yr cancer-specific survival estimates were 36% (95% confidence interval [CI] 25-52%) for SkM+ and 66% (95% CI 55-80%) for matched SkM- patients (p < 0.001). On multivariable Cox regression analysis, SkM presence was an independent predictor for higher CSM (hazard ratio 2.05, 95% CI 1.06-4,12; p = 0.03). CONCLUSIONS: PSCC-related SkM is associated with aggressive disease behaviour and poor survival outcomes. Palpation of the entire penile shaft is essential, and distant staging is recommended in patients suspected of having SkM owing to the tendency for distant metastatic spread. PATIENT SUMMARY: We investigated outcomes for patients with cancer of the penis who had metastases in the tissues responsible for erection. We found that metastases in this location were associated with poor prognosis, even in the absence of more typical spread of cancer via the lymph nodes.

10.
ANZ J Surg ; 92(9): 2094-2101, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36097430

RESUMO

BACKGROUND: Superior patient outcomes rely on surgical training being optimized. Accordingly, we conducted an international, prospective, cross-sectional study determining relative impacts of COVID-19, gender, race, specialty and seniority on mental health of surgical trainees. METHOD: Trainees across Australia, New Zealand and UK enrolled in surgical training accredited by the Royal Australasian College of Surgeons or Royal College of Surgeons were included. Outcomes included the short version of the Perceived Stress Scale, Oxford Happiness Questionnaire short scale, Patient Health Questionnaire-2 and the effect on individual stress levels of training experiences affected by COVID-19. Predictors included trainee characteristics and local COVID-19 prevalence. Multivariable linear regression analyses were conducted to assess association between outcomes and predictors. RESULTS: Two hundred and five surgical trainees were included. Increased stress was associated with number of COVID-19 patients treated (P = 0.0127), female gender (P = 0.0293), minority race (P = 0.0012), less seniority (P = 0.001), and greater COVID-19 prevalence (P = 0.0122). Lower happiness was associated with training country (P = 0.0026), minority race (P = 0.0258) and more seniority (P < 0.0001). Greater depression was associated with more seniority (P < 0.0001). Greater COVID-19 prevalence was associated with greater reported loss of training opportunities (P = 0.0038), poor working conditions (P = 0.0079), personal protective equipment availability (P = 0.0008), relocation to areas of little experience (P < 0.0001), difficulties with career progression (P = 0.0172), loss of supervision (P = 0.0211), difficulties with pay (P = 0.0034), and difficulties with leave (P = 0.0002). CONCLUSION: This is the first study to specifically describe the relative impacts of COVID-19 community prevalence, gender, race, surgical specialty and level of seniority on stress, happiness and depression of surgical trainees on an international scale.


Assuntos
COVID-19 , Especialidades Cirúrgicas , COVID-19/epidemiologia , Estudos Transversais , Feminino , Humanos , Saúde Mental , Estudos Prospectivos , Especialidades Cirúrgicas/educação
11.
J Biol Chem ; 285(49): 38415-27, 2010 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-20889977

RESUMO

Opioid receptor signaling via EGF receptor (EGFR) transactivation and ERK/MAPK phosphorylation initiates diverse cellular responses that are cell type-dependent. In astrocytes, multiple µ opioid receptor-mediated mechanisms of ERK activation exist that are temporally distinctive and feature different outcomes. Upon discovering that chronic opiate treatment of rats down-regulates thrombospondin 1 (TSP1) expression in the nucleus accumbens and cortex, we investigated the mechanism of action of this modulation in astrocytes. TSP1 is synthesized in astrocytes and is released into the extracellular matrix where it is known to play a role in synapse formation and neurite outgrowth. Acute morphine (hours) reduced TSP1 levels in astrocytes. Chronic (days) opioids repressed TSP1 gene expression and reduced its protein levels by µ opioid receptor and ERK-dependent mechanisms in astrocytes. Morphine also depleted TSP1 levels stimulated by TGFß1 and abolished ERK activation induced by this factor. Chronic morphine treatment of astrocyte-neuron co-cultures reduced neurite outgrowth and synapse formation. Therefore, inhibitory actions of morphine were detected after both acute and chronic treatments. An acute mechanism of morphine signaling to ERK that entails depletion of TSP1 levels was suggested by inhibition of morphine activation of ERK by a function-blocking TSP1 antibody. This raises the novel possibility that acute morphine uses TSP1 as a source of EGF-like ligands to activate EGFR. Chronic morphine inhibition of TSP1 is reminiscent of the negative effect of µ opioids on EGFR-induced astrocyte proliferation via a phospho-ERK feedback inhibition mechanism. Both of these variations of classical EGFR transactivation may enable opiates to diminish neurite outgrowth and synapse formation.


Assuntos
Astrócitos/metabolismo , Morfina/farmacologia , Entorpecentes/farmacologia , Neuritos/metabolismo , Sinapses/metabolismo , Trombospondina 1/biossíntese , Animais , Linhagem Celular Transformada , Proliferação de Células , Córtex Cerebral/metabolismo , Ativação Enzimática/efeitos dos fármacos , Receptores ErbB , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Núcleo Accumbens/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores Opioides mu/agonistas , Receptores Opioides mu/metabolismo , Fatores de Tempo , Fator de Crescimento Transformador beta1/metabolismo
14.
Neuron ; 101(3): 394-398, 2019 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-30731065

RESUMO

The NIH Brain Research through Advancing Innovative Neurotechnologies (BRAIN) Initiative is focused on developing new tools and neurotechnologies to transform our understanding of the brain, and neuroethics is an essential component of this research effort. Coordination with other brain projects around the world will help maximize success.


Assuntos
National Institutes of Health (U.S.)/ética , Neurociências/ética , Bioética , Humanos , National Institutes of Health (U.S.)/normas , Neurociências/métodos , Neurociências/organização & administração , Guias de Prática Clínica como Assunto , Estados Unidos
16.
Neurosci Lett ; 405(1-2): 10-3, 2006 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-16824681

RESUMO

In the present study, we examined the relationship between post-injury survival duration and receptive field size at multiple levels of the ascending somatosensory neuroaxis. In experimentally naïve subjects, receptive fields on the glabrous hand are typically restricted to single digits. Yet, following targeted nerve section, receptive fields often span multiple digits. In these experiments, adult squirrel monkeys were subject to paired transections of the median and ulnar nerves and permitted to survive for varying periods (2-28 months) prior to terminal electrophysiological recording. The frequency of cutaneously activated multiple-digit receptive fields was evaluated in regions of brainstem, thalamus and cortex normally devoted to the (now) partially deafferented hand. We report that for area 3b of primary somatosensory cortex, receptive field size became smaller as a function of survival duration. In contrast, survival duration had no appreciable effect on the frequency of multiple-digit receptive fields in either the cuneate nucleus of the brainstem or the ventroposterior lateral nucleus of the thalamus. These observations suggest that the mechanisms responsible for the refinement of receptive fields are, primarily, resident to the cortex.


Assuntos
Nervo Mediano/lesões , Córtex Somatossensorial/fisiopatologia , Nervo Ulnar/lesões , Animais , Tronco Encefálico/fisiopatologia , Eletrofisiologia , Plasticidade Neuronal , Saimiri , Tálamo/fisiopatologia , Fatores de Tempo
17.
PeerJ ; 4: e1770, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27114859

RESUMO

A research cruise to Hannibal Bank, a seamount and an ecological hotspot in the coastal eastern tropical Pacific Ocean off Panama, explored the zonation, biodiversity, and the ecological processes that contribute to the seamount's elevated biomass. Here we describe the spatial structure of a benthic anomuran red crab population, using submarine video and autonomous underwater vehicle (AUV) photographs. High density aggregations and a swarm of red crabs were associated with a dense turbid layer 4-10 m above the bottom. The high density aggregations were constrained to 355-385 m water depth over the Northwest flank of the seamount, although the crabs also occurred at lower densities in shallower waters (∼280 m) and in another location of the seamount. The crab aggregations occurred in hypoxic water, with oxygen levels of 0.04 ml/l. Barcoding of Hannibal red crabs, and pelagic red crabs sampled in a mass stranding event in 2015 at a beach in San Diego, California, USA, revealed that the Panamanian and the Californian crabs are likely the same species, Pleuroncodes planipes, and these findings represent an extension of the southern endrange of this species. Measurements along a 1.6 km transect revealed three high density aggregations, with the highest density up to 78 crabs/m(2), and that the crabs were patchily distributed. Crab density peaked in the middle of the patch, a density structure similar to that of swarming insects.

18.
Neurobiol Aging ; 23(5): 941-55, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12392797

RESUMO

While limited research is available, evidence indicates that physical and mental activity influence the aging process. Human data show that executive functions of the type associated with frontal lobe and hippocampal regions of the brain may be selectively maintained or enhanced in humans with higher levels of fitness. Similarly enhanced performance is observed in aged animals exposed to elevated physical and mental demand and it appears that the vascular component of the brain response may be driven by physical activity whereas the neuronal component may reflect learning. Recent results have implicated neurogenesis, at least in the hippocampus, as a component of the brain response to exercise, with learning enhancing survival of these neurons. Non-neuronal tissues also respond to experience in the mature brain, indicating that the brain reflects both its recent and its longer history of experience. Preliminary measures of brain function hold promise of increased interaction between human and animal researchers and a better understanding of the substrates of experience effects on behavioral performance in aging.


Assuntos
Envelhecimento/fisiologia , Encéfalo/fisiologia , Cognição/fisiologia , Exercício Físico/fisiologia , Aprendizagem/fisiologia , Idoso , Animais , Humanos
19.
Neurobiol Aging ; 24(6): 883-92, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12927770

RESUMO

Numerous types of age-related deficits in the nervous system have been well documented. While a distinction between general types of memories that are susceptible to compromise with advanced age has been fairly well agreed upon, it is often difficult to determine exactly which specific processes are detrimentally influenced. In this study, we used a paradigm that enabled us to distinguish between effects associated with gross motor deficits and those due to learning and memory of a motor skill, per se. In terms of both latency and errors, senescent animals were, on average, impaired in their ability to traverse an elevated obstacle course, compared to younger animals. Yet, if gross motor abilities are accounted for, a fraction of these deficits is readily explained. Moreover, if individual baseline performance differences are normalized, no memory differences are evident across age groups. These observations suggest that memory for a procedural task is not impaired with advanced age.


Assuntos
Envelhecimento/fisiologia , Aprendizagem/fisiologia , Destreza Motora/fisiologia , Prática Psicológica , Tempo de Reação/fisiologia , Animais , Feminino , Ratos , Ratos Endogâmicos F344 , Fatores de Tempo
20.
BMC Neurosci ; 5: 43, 2004 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-15533258

RESUMO

BACKGROUND: Topographic reorganization of central maps following peripheral nerve injury has been well characterized. Despite extensive documentation of these physiological changes, the underlying anatomical correlates have yet to be fully explored. In this study, we used Golgi impregnation and light microscopy to assess dendritic morphology following denervation of the glabrous hand surface in adult primates. RESULTS: After survival durations that permit complete physiologically-defined reorganization, we find a systematic change in the dendritic arborization pattern of both layer II/III pyramidal and layer IV spiny stellate cells in the contralateral hand region of area 3b, compared to unaffected cortical areas. In general, our analyses indicate a progressive expansion of distal regions of the dendritic arbor with no appreciable changes proximally. This pattern of distal dendritic elaboration occurs for both basilar and apical dendrites. CONCLUSIONS: These observations are consistent with the notion that latent inputs gain expression in reorganized cortex after nerve injury via their influence through contacts with more distally located termination sites.


Assuntos
Dendritos/ultraestrutura , Córtex Somatossensorial/lesões , Córtex Somatossensorial/patologia , Animais , Denervação , Células Piramidais/patologia , Saimiri , Córtex Somatossensorial/citologia
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