RESUMO
Incidental memory can be challenged by increasing either the retention delay or the memory load. The dorsal hippocampus (dHP) appears to help with both consolidation from short-term (STM) to long-term memory (LTM), and higher memory loads, but the mechanism is not fully understood. Here we find that female mice, despite having the same STM capacity of 6 objects and higher resistance to distraction in our different object recognition task (DOT), when tested over 1 h or 24 h delays appear to transfer to LTM only 4 objects, whereas male mice have an STM capacity of 6 objects in this task. In male mice the dHP shows greater activation (as measured by c-Fos expression), whereas female mice show greater activation of the ventral midline thalamus (VMT). Optogenetic inhibition of the VMT-dHP pathway during off-line memory consolidation enables 6-object LTM retention in females, while chemogenetic VMT-activation impairs it in males. Thus, removing or enhancing sub-cortical inhibitory control over the hippocampus leads to differences in incidental memory.
Assuntos
Consolidação da Memória , Memória de Curto Prazo , Animais , Feminino , Hipocampo/fisiologia , Inibição Psicológica , Masculino , Memória de Longo Prazo/fisiologia , Memória de Curto Prazo/fisiologia , CamundongosRESUMO
Spiral shapes occur frequently in nature as in the case of snail shells or the cochlea - the auditory portion of the inner ear. They also inspire many technological devices that take advantage of this geometry. Here we show that µ-pyro-electrospinning is able to control whipping instabilities in order to form spiralling fibres (down to 300 nm thick) directly on a support with true microscale regularity. The results show that polymer concentration plays a key role in producing reliable and long spirals. We investigate the cell response to these spiral templates that, thanks to their true regularity, would be useful for developing innovative cochlea regeneration scaffolds.
RESUMO
Stable chains of carbon-based nanoparticles were formed directly in polymer matrixes through an electrode-free approach. Spontaneous surface charges were generated pyroelectrically onto functionalized ferroelectric crystals, enabling the formation of electric field gradients that triggered the dipole-dipole interactions responsible for the alignment of the particles, while embedded in the polymer solution. The phenomenon is similar to the dielectrophoretic alignment of carbon nanotubes reported in the literature. However, here the electric fields are generated spontaneously by a simple heat treatment that, simultaneously, aligns the particles and provides the energy necessary for curing the host polymer. The result is a polymer sheet reinforced with well-aligned chains of carbon-based particles, avoiding the invasive implementation of appropriate electrodes and circuits. Because polymers with anisotropic features are of great interest for enhancing the thermal and/or the electrical conductivity, the electrode-free nature of this technique would improve the scaling down and the versatility of those interconnections that find applications in many fields, such as electronics, sensors, and biomedicine. Theoretical simulations of the interactions between the particles and the charge templates were implemented and appear in good agreement with the experimental results. The chain formation was characterized by controlling different parameters, including surface charge configuration, particle concentration, and polymer viscosity, thus demonstrating the reliability of the technique. Moreover, micro-Raman spectroscopy and scanning electron microscopy were used for a thorough inspection of the assembled chains.
Assuntos
Carbono/química , Polímeros/química , Microscopia Eletrônica de Varredura , Propriedades de SuperfícieRESUMO
A completely numerical method, named digital self-referencing holography, is described to easily accomplish a quantitative phase microscopy for microfluidic devices by a digital holographic microscope. The approach works through an appropriate numerical manipulation of the retrieved complex wavefront. The self-referencing is obtained by folding the retrieved wavefront in the image plane. The folding operation allows us to obtain the correct phase map by subtracting from the complex region of interest a flat area outside the microfluidic channel. To demonstrate the effectiveness of the method, quantitative phase maps of bovine spermatozoa and in vitro cells are retrieved.
Assuntos
Holografia/métodos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Microscopia de Contraste de Fase/métodos , Células 3T3 , Algoritmos , Animais , Bovinos , Desenho de Equipamento/métodos , Holografia/instrumentação , Aumento da Imagem/instrumentação , Interpretação de Imagem Assistida por Computador/instrumentação , Processamento de Imagem Assistida por Computador/métodos , Masculino , Camundongos , Microscopia/instrumentação , Microscopia/métodos , Microscopia de Contraste de Fase/instrumentação , Processamento de Sinais Assistido por Computador , Espermatozoides/citologiaRESUMO
Hedrocele represents an unusual variant of the rare posterior perineal hernia and results from a defect in the rectogenital septum. We report two cases of obstructive defecation syndrome (ODS) related to presence of hedrocele successfully treated by laparoscopy-assisted transanal surgery.
Assuntos
Canal Anal/cirurgia , Constipação Intestinal , Defecação , Laparoscopia/métodos , Prolapso Retal/cirurgia , Idoso , Canal Anal/diagnóstico por imagem , Canal Anal/fisiopatologia , Defecografia , Procedimentos Cirúrgicos do Sistema Digestório/métodos , Feminino , Humanos , Pessoa de Meia-Idade , Proctoscopia , Qualidade de Vida , Recuperação de Função Fisiológica , Prolapso Retal/diagnóstico , Prolapso Retal/fisiopatologia , Fatores de Risco , Síndrome , Resultado do TratamentoRESUMO
An optical phase array with tunable phase step is demonstrated. The phase array consists of a two-dimensional hexagonal lattice of inverted ferroelectric domains fabricated on a Z-cut lithium niobate substrate. The electro-optically tunable phase step is obtained by the application of an external electric field along the z axis of the crystal via transparent electrodes. Theoretical analysis and experimental results are presented, showing that a tunable and flexible adaptive optical illuminator device can be realized by combining the electro-optic tunability with the Talbot effect. Generation of a multiplicity of light patterns is shown.
RESUMO
BACKGROUND: Intracranial haemorrhage (ICH) is the type of stroke associated with the highest death rate, and about 30% of ICH occurs in patients on antithrombotic treatment. This study relates clinical presentations and outcome of ICH patients on oral anticoagulant (OA) or antiplatelet (AP) therapy admitted to 33 Italian emergency departments (ED). METHODS: Consecutive patients were enrolled after cranial computed tomography (CT). Primary outcome was the Modified Rankin Scale (MRS) score at 3 months of follow-up. Common descriptive statistics were computed after stratification for traumatic or spontaneous ICH and identification of the anatomical location of bleeding. Multivariate logistic regression was used to assess predictors of death. RESULTS: We recruited 434 patients on AP therapy and 232 on OA. There were 432 spontaneous and 234 traumatic ICH patients. The proportions of AP and OA patients undergoing neurosurgery were 21.8 and 19.4%, respectively, while < 30% underwent procoagulant medical treatment. At the 3-month follow-up, the case fatality rate was 42.0%, while disability or death (MRS 3-6) was 68.1%. The odds ratio for death in OA versus AP patients was 2.63 (95% CI 1.73-4.00) in the whole population and 2.80 (95% CI 1.77-4.41) in intraparenchymal event patients. Glasgow Coma Scale, age, spontaneous event and anticoagulant use were found to be predictors of death both in traumatic and spontaneous events. CONCLUSION: This study confirms the high prevalence of death or disability in OA and AP patients with ICH. As far as the determinants of mortality and disability are concerned, the results of this study might be useful in the clinical management and allocation of resources in the ED setting. The observed low use of procoagulant therapy highlights the need for ED educational programmes to heighten the awareness of available and effective haemostatic treatments.
Assuntos
Anticoagulantes/uso terapêutico , Coagulantes/uso terapêutico , Serviço Hospitalar de Emergência , Fibrinolíticos/uso terapêutico , Hemorragias Intracranianas/tratamento farmacológico , Inibidores da Agregação Plaquetária/uso terapêutico , Acidente Vascular Cerebral/tratamento farmacológico , Administração Oral , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticoagulantes/administração & dosagem , Feminino , Humanos , Hemorragias Intracranianas/mortalidade , Hemorragias Intracranianas/reabilitação , Itália , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Recuperação de Função Fisiológica , Acidente Vascular Cerebral/mortalidade , Reabilitação do Acidente Vascular Cerebral , Análise de Sobrevida , Tromboembolia/tratamento farmacológicoRESUMO
Acute necrotizing pancreatitis involves high mortality. When diagnosed, the disease implies a choice of suitable timing and proper technique of surgical approach. The experience on 16 patients with acute necrotizing pancreatitis, 9 males and 7 females, mean age of 54.7 +/- 3.3 years, is presented in this study. Necrosectomy and continuous local lavage of abdominal collections and pancreatic necrotic surfaces was the most appropriate surgical treatment. The method seems able to remove necrosis and active biological compounds and would appear to achieve a limited mortality and morbidity. Necrosectomy and postoperative local lavage represent a therapeutic effective procedure.
Assuntos
Necrose/cirurgia , Pancreatite/cirurgia , Lavagem Peritoneal , Doença Aguda , Adulto , Idoso , Drenagem , Estudos de Avaliação como Assunto , Feminino , Hemorragia/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Pancreatite/complicações , Pancreatite/mortalidade , Cuidados Pós-OperatóriosRESUMO
OBJECTIVES: The aim of this study was to compare risk factors for coronary atherosclerosis in children with a family history of unheralded myocardial infarction or uncomplicated stable angina. BACKGROUND: In patients with unheralded myocardial infarction, coronary atherosclerosis might have a greater tendency to cause acute coronary occlusion than in patients with uncomplicated stable angina, suggesting the possibility of different risk factors in these two groups of patients. METHODS: Serum lipid levels were compared in children with a family history of unheralded myocardial infarction (236 children) or uncomplicated stable angina (48 children) or no family history of ischemic heart disease (613 children). RESULTS: Mean (+/- 1 SD) total serum cholesterol was higher in children with a family history of myocardial infarction than in control subjects (161 +/- 28 vs. 154 +/- 25 mg%, p < 0.01). In children with a family history of stable angina, mean total serum cholesterol (159 +/- 25 mg%) was similar to that in children with family history of myocardial infarction. High density lipoprotein cholesterol and apolipoprotein A-I were higher in children with family history of stable angina than in children with family history of myocardial infarction and control subjects (69 +/- 18 vs. 61 +/- 13 and 60 +/- 13 mg%, p < 0.01; 143 +/- 23 vs. 130 +/- 18 and 129 +/- 18 mg%, p < 0.01, respectively). In children with a family history of myocardial infarction, the low density/high density lipoprotein cholesterol ratio was significantly higher than in control subjects (1.53 +/- 0.64 vs. 1.44 +/- 0.56, p < 0.05). Conversely, in children with a family history of stable angina, this ratio (1.24 +/- 0.51) was significantly lower (p < 0.05) than in control subjects. CONCLUSIONS: Risk factors for coronary athersclerosis in children with a family history of unheralded myocardial infarction are different from those in children with a family history of uncomplicated stable angina. Higher levels of apolipoprotein A-I early in life might reduce the risk of acute coronary syndromes.
Assuntos
Angina Pectoris/epidemiologia , Infarto do Miocárdio/epidemiologia , Adulto , Angina Pectoris/sangue , Angina Pectoris/genética , Apolipoproteínas/análise , Criança , Feminino , Humanos , Itália/epidemiologia , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Infarto do Miocárdio/sangue , Infarto do Miocárdio/genética , Isquemia Miocárdica/sangue , Isquemia Miocárdica/epidemiologia , Isquemia Miocárdica/genética , Fatores de Risco , Distribuição por SexoAssuntos
Procedimentos Cirúrgicos do Sistema Biliar/métodos , Colelitíase/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Procedimentos Cirúrgicos do Sistema Biliar/estatística & dados numéricos , Colelitíase/complicações , Colelitíase/mortalidade , Drenagem/métodos , Drenagem/estatística & dados numéricos , Feminino , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologiaRESUMO
1. The effect of bombesin, a neurogastrointestinal peptide, on basal and stimulated insulin release was studied in man. 2. Two different stimuli were used, hyperglycaemic (20 g glucose) and hypoglycaemic (1 g tolbutamide). They were injected intravenously to two groups of male healthy volunteers during saline or bombesin (5 ng kg-1 min-1 for 60 min) infusion. 3. The peptide had no significant effect on basal levels of glucose and insulin. However, the insulin response to intravenous glucose was strongly potentiated by bombesin, the integrated insulin response being 2.23 +/- 0.59 mu ml-1 . 90 min and 0.98 +/- 0.19 mu ml-1 . 90 min during infusion of bombesin and saline, respectively (P less than 0.05). The behaviour of plasma glucose was not significantly modified by the peptide. Indeed, the glucose disappearance rate (K of Conard, mg min 10(-2)) changed from 2.5 +/- 0.3 during saline to 2.4 +/- 0.4 during bombesin infusion. 4. When the hypoglycaemic stimulus (i.e. tolbutamide) was used, no effect of the peptide on insulin release could be detected. Here again, the drop in plasma glucose (expressed as Marigo's coefficient) was not affected by the peptide, with a value of 92.8 +/- 12.6 and 84.0 +/- 10.9 during bombesin and saline administration. 5. These data therefore show that, at normal or low blood glucose levels, the dose of bombesin used is unable to modify insulin release and suggest that this peptide might be regarded as a glucose-dependent insulinotropic peptide.
Assuntos
Bombesina/farmacologia , Glucose/farmacologia , Insulina/metabolismo , Tolbutamida/farmacologia , Adulto , Glicemia/metabolismo , Pressão Sanguínea/efeitos dos fármacos , Temperatura Corporal/efeitos dos fármacos , Bombesina/efeitos adversos , Teste de Tolerância a Glucose , Frequência Cardíaca/efeitos dos fármacos , Humanos , Insulina/sangue , Masculino , Respiração/efeitos dos fármacos , Tolbutamida/efeitos adversosRESUMO
The effect of bombesin on basal and glucose-stimulated insulin release was studied in male healthy volunteers. Glucose was administered by oral, intravenous or intraduodenal route during saline or bombesin infusion (5 ng/kg/min for 60 min). The peptide had no significant effect on basal levels of glucose and insulin. However, during its administration, the insulin response and the expected rise in blood glucose after oral glucose load (50 g) were strongly inhibited, and the gastric emptying of liquids was significantly delayed. On the contrary, the insulin response to intravenous glucose (20 g) was significantly increased by bombesin without changes in plasma glucose levels. Finally, when glucose was infused into the duodenum, thus bypassing the stomach, the insulin response was significantly increased by the peptide. In this case, too, plasma glucose levels after glucose load were virtually identical during either bombesin or saline infusion. These data clearly demonstrate that the direct effect of bombesin on insulin release is stimulatory and suggest that the inhibitory effect observed after oral glucose is connected with the action of the peptide on gastric emptying, the delay of which slows the entry of glucose into the small bowel.
Assuntos
Bombesina/farmacologia , Esvaziamento Gástrico/efeitos dos fármacos , Glucose/administração & dosagem , Insulina/metabolismo , Administração Oral , Adulto , Bombesina/administração & dosagem , Depressão Química , Interações Medicamentosas , Nutrição Enteral , Humanos , Injeções Intravenosas , Secreção de Insulina , MasculinoRESUMO
Biliary obstruction by non-malignant lesions can be treated either by biliary-enteric anastomosis or by sphincterotomy or sphincteroplasty. In the present report, 153 jaundiced patients operated on by sphincterotomy, were retrospectively examined. Proper indications for surgical sphincterotomy have been considered as follows: stones in the common bile duct (49.7%), biliary stones with secondary stenosis of Oddi (26.8%), impacted ampullary stones (17.6%), primary stenosis of Oddi (3.9%), stenosis of Oddi by perivaterian chronic pancreatitis (2.0%). Preoperative early diagnosis was recognized by US, ERCP, PTC, CT. The overall operative mortality was 2.6% and determined by acute renal failure in 2.0% and acute pancreatitis in 0.6%. Postoperative complications occurred in 4.6% and consisted in acute pancreatitis in 3.3% and bleeding from sphincterotomy in 1.3%. One hundred and twenty-three patients (82.5%) were followed up by questionnaire and by both X-ray studies and ultrasonography. Good results were observed in 80.5%, fair results in 17.1% and poor results in 2.4%. The presents study suggests further indications for surgical sphincterotomy in the treatment of benign biliary obstruction. The effectiveness of this procedure in the early management of non-malignant jaundice is also stressed.
Assuntos
Ampola Hepatopancreática/cirurgia , Colestase/cirurgia , Esfíncter da Ampola Hepatopancreática/cirurgia , Adulto , Idoso , Colangiopancreatografia Retrógrada Endoscópica , Colestase/diagnóstico , Colestase/diagnóstico por imagem , Feminino , Cálculos Biliares/cirurgia , Humanos , Masculino , Métodos , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Estudos Retrospectivos , UltrassonografiaRESUMO
On the basis of personal experience, the possibility and the limits of galactography are discussed. Galactography has been used by the authors in any cases of discharge from the nipple, and has shown to be the only radiological examination able to discover intraductal tumours. Furthermore it allows to establish the site and extension of the lesions. Among the limits of the method the impossibility to distinguish between benign and malignant lesions is stressed out.
Assuntos
Doenças Mamárias/diagnóstico por imagem , Neoplasias da Mama/diagnóstico por imagem , Carcinoma Intraductal não Infiltrante/diagnóstico por imagem , Lesões Pré-Cancerosas/diagnóstico por imagem , Feminino , Humanos , RadiografiaRESUMO
The intrasplenic autotransplant of pancreatic fragments in dogs subjected to total pancreatectomy can prevent diabetes as it maintains normoglycaemic condition and a normal insulinaemic response to i.v. infusion of glucose. By adopting a pancreatic tissue preparation technique which provides for a very short collagenasis digestion time (4 minutes), B cells took and normal glucidic metabolism was maintained.