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1.
J Neuroophthalmol ; 35(1): 16-21, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25259863

RESUMO

BACKGROUND: Ocular motor abnormalities reflect the varied neuropathology of spinocerebellar ataxias (SCAs) and may serve to clinically distinguish the different SCAs. We analyzed the various eye movement abnormalities detected prospectively at the baseline visit during a large multicenter natural history study of SCAs 1, 2, 3, and 6. METHODS: The data were prospectively collected from 12 centers in the United States in patients with SCAs 1, 2, 3, and 6, as part of the Clinical Research Consortium for Spinocerebellar Ataxias (NIH-CRC-SCA). Patient characteristics, ataxia rating scales, the Unified Huntington Disease Rating Scale functional examination, and clinical staging were used. Eye movement abnormalities including nystagmus, disorders of saccades and pursuit, and ophthalmoparesis were recorded, and factors influencing their occurrence were examined. RESULTS: A total of 301 patients participated in this study, including 52 patients with SCA 1, 64 with SCA 2, 117 with SCA 3, and 68 with SCA 6. Although no specific ocular motor abnormality was pathognomonic to any SCA, significant differences were noted in their occurrence among different disorders. SCA 6 was characterized by frequent occurrence of nystagmus and abnormal pursuit and rarity of slow saccades and ophthalmoparesis and SCA 2 by the frequent occurrence of slow saccades and infrequent nystagmus and dysmetric saccades. SCA 1 and SCA 3 subjects had a more even distribution of eye movement abnormalities. CONCLUSIONS: Prospective data from a large cohort of patients with SCAs 1, 2, 3, and 6 provide statistical validation that the SCAs exhibit distinct eye movement abnormalities that are useful in identifying the genotypes. Many of the abnormalities correlate with greater disease severity measures.


Assuntos
Transtornos da Motilidade Ocular/diagnóstico , Transtornos da Motilidade Ocular/etiologia , Ataxias Espinocerebelares/complicações , Adulto , Feminino , Testes Genéticos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Índice de Gravidade de Doença , Ataxias Espinocerebelares/classificação , Ataxias Espinocerebelares/genética , Estados Unidos
3.
Neurology ; 71(11): 856-9, 2008 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-18779514

RESUMO

BACKGROUND: The term essential tremor has been in regular use since the second half of the 20th century. To modern neurologists, the word "essential" may seem cryptic. The historical underpinnings of this term have not been examined. OBJECTIVES: To bring to attention early medical reports using the term essential tremor and examine the characteristics of the disorder that contributed to the proposed use of the term. METHODS: Review of 19th and early 20th century medical literature on essential tremor. RESULTS: The term tremore semplice essenziale (simple essential tremor) was first used by Burresi (Italy, 1874) to describe an 18-year-old man with severe, isolated action tremor. Several years later, Maragliano (Italy, 1879), Nagy (Austria, 1890), and Raymond (France, 1892) described similar cases and proposed the terms tremore essenziale congenito (essential congenital tremor), essentieller Tremor (essential tremor), and tremblement essentiel héréditaire (hereditary essential tremor) to define the illness. Mirroring contemporaneous views of constitutional and inherited disease, the key ingredients of the disorder were viewed as the constant presence of tremor in the absence of other neurologic signs and its heritable nature. By the early 20th century, the term began to appear in the medical literature with greater frequency. CONCLUSIONS: Toward the end of the 19th century, several clinicians attempted to provide a nosologic separation for a tremor diathesis that was often familial and occurred in isolation of other neurologic signs. This disorder, which was termed essential tremor, was later recognized as one of the most common neurologic disorders.


Assuntos
Tremor Essencial/história , Tremor Essencial/classificação , História do Século XIX , História do Século XX , Humanos , Terminologia como Assunto
4.
J Chemother ; 14(4): 366-72, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12420854

RESUMO

Amoxicillin/clavulanic acid (amoxicillin 2 g/clavulanic acid 200 mg) has been administered in comparison to cefotaxime (2 g) for antimicrobial prophylaxis in 476 evaluable patients undergoing abdominal surgery at high risk of septic complications. Both antibiotics were administered as a single infusion. 205 evaluable patients (110 in amoxicillin/clavulanic acid group and 95 in cefotaxime group) underwent upper gastrointestinal surgery (including gastroduodenal and biliary surgery). The wound infection rate was 4.5% for amoxicillin/clavulanic acid and 7.4% for cefotaxime, with no significant differences. Intra-abdominal abscesses were observed in 3 patients in the amoxicillin/clavulanic acid group and in 1 patient in the cefotaxime group. 271 evaluable patients (135 in amoxicillin/clavulanic acid group and 136 in cefotaxime group) underwent lower gastrointestinal surgery (including colorectal surgery). The wound infection rate was 11% for amoxicillin/clavulanic acid and 13% for cefotaxime, with no significant differences. A purulent discharge was present in 3 patients in both groups. Intra-abdominal abscesses were observed in 3 patients in the amoxicillin/clavulanic acid group and in 4 patients in the cefotaxime group. No serious adverse events and no cases of diarrhea were observed. In conclusion, in our experience amoxicillin/clavulanic acid proved to be as effective as cefotaxime in protecting patients from surgical infections in abdominal surgery. Its use in surgical prophylaxis may help decrease the cost of treatment and reduce the risk of resistance to antibiotics and superinfections.


Assuntos
Abdome/cirurgia , Amoxicilina/uso terapêutico , Antibacterianos/uso terapêutico , Antibioticoprofilaxia , Cefotaxima/uso terapêutico , Ácido Clavulânico/uso terapêutico , Quimioterapia Combinada/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Infecções Bacterianas/prevenção & controle , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/prevenção & controle , Infecção da Ferida Cirúrgica/prevenção & controle
6.
Pediatr Neurol ; 23(3): 252-5, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11033289

RESUMO

We describe a child with human immunodeficiency virus infection who presented with a large subarachnoid hemorrhage. She had multiple saccular and fusiform aneurysms in the proximal cerebral arterial circulation and no evidence of bacterial or fungal infection. The arteriopathy coincided with a high human immunodeficiency virus RNA load. Human immunodeficiency virus may cause cerebral arteriopathy with potentially life-threatening complications.


Assuntos
Complexo AIDS Demência/diagnóstico , Aneurisma Intracraniano/diagnóstico , Angiografia Cerebral , Criança , Feminino , Humanos , Angiografia por Ressonância Magnética , Hemorragia Subaracnóidea/diagnóstico , Carga Viral
7.
8.
J Neurophysiol ; 81(4): 1827-38, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10200217

RESUMO

Previous studies from our laboratory identified a parietal eye field in the primate lateral intraparietal sulcus, the lateral intraparietal area (area LIP). Here we further explore the role of area LIP in processing saccadic eye movements by observing the effects of reversible inactivation of this area. One to 2 microl of muscimol (8 mg/ml) were injected at locations where saccade-related activities were recorded for each lesion experiment. After the muscimol injection we observed in two macaque monkeys consistent effects on both the metrics and dynamics of saccadic eye movements at many injection sites. These effects usually took place within 10-30 min and disappeared after 5-6 h in most cases and certainly when tested the next day. After muscimol injection memory saccades directed toward the contralesional and upper space became hypometric, and in one monkey those to the ipsilesional space were slightly but significantly hypermetric. In some cases, the scatter of the end points of memory saccades was also increased. On the other hand, the metrics of visual saccades remained relatively intact. Latency for both visual and memory saccades toward the contralesional space was increased and in many cases displayed a higher variance after muscimol lesion. At many injection sites we also observed an increase of latency for visual and memory saccades toward the upper space. The peak velocities for memory saccades toward the contralesional space were decreased after muscimol injection. The peak velocities of visual saccades were not significantly different from those of the controls. The duration of saccadic eye movements either to the ipsilesional or contralesional space remained relatively the same for both visual and memory saccades. Overall these results demonstrated that we were able to selectively inactivate area LIP and observe effects on saccadic eye movements. Together with our previous recording studies these results futher support the view that area LIP plays a direct role in processing incoming sensory information to program saccadic eye movements. The results are consistent with our unit recording data and microstimulation studies, which suggest that area LIP represents contralateral space and also has a bias for the upper visual field.


Assuntos
Memória/fisiologia , Lobo Parietal/fisiologia , Movimentos Sacádicos/fisiologia , Percepção Visual/fisiologia , Animais , Atenção/fisiologia , Comportamento Animal/fisiologia , Condicionamento Psicológico/fisiologia , Eletrofisiologia , Lateralidade Funcional/fisiologia , Agonistas GABAérgicos/farmacologia , Macaca , Memória/efeitos dos fármacos , Muscimol/farmacologia , Nervo Oculomotor/citologia , Nervo Oculomotor/fisiologia , Desempenho Psicomotor/fisiologia , Tempo de Reação/fisiologia , Movimentos Sacádicos/efeitos dos fármacos
9.
Oncol Res ; 11(9): 437-45, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10821538

RESUMO

Patients with advanced colorectal cancer are currently being treated with 5-fluorouracil (5-FU)-based chemotherapy. A growing number of patients with resectable disease receive adjuvant therapy with 5-FU/levamisole (LEV) or 5-FU/folinic acid (LV). However, many patients still fail on these treatments, due to occurrence of natural or acquired tumor resistance. Among clinically relevant mechanisms of resistance to fluoropyrimidines, increased expression of thymidylate synthase (TS) has been emphasized. Another potentially relevant mechanism involves a decrease in folylpolyglutamate synthetase (FPGS) expression. To establish the value of these genes as prognostic factors and predictors of the outcome of 5-FU-based chemotherapy in colorectal cancer, we measured their expression in colorectal tumors from patients undergoing surgery and postoperative chemotherapy and compared it with that in normal colonic mucosa. This was done by a semi quantitative, nonradioisotopic polymerase chain reaction (PCR) method using beta-actin as an internal standard and expressed as a TS/beta-actin or a FPGS/beta-actin mRNA ratio. In tumor samples from 21 colorectal cancer patients, TS gene expression varied 118-fold. The median TS/beta-actin ratio was, in fact, 41.36 x 10(-3) (range 2.49 x 10(-3) to 294.54 x 10(-3)). Little variation in TS gene expression was observed in corresponding normal colic mucosa; the TS/beta-actin gene ratio was lower (median 26.16 x 10(-3); range 8.49 x 10(-3) to 69.49 x 10(-3)). Among tumor explants from 20 patients, FPGS expression varied over 161-fold. A similar marked variation was also observed in normal colonic mucosal samples (over 185-fold). Overall and disease-free survival data suggest an inverse association between the level of tumor TS and FPGS expression and clinical prognosis. The availability of this sensitive and accurate assay for gene expression should now make it possible to extend these laboratory/clinical correlations to larger populations.


Assuntos
Neoplasias Colorretais/enzimologia , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Peptídeo Sintases/genética , Timidilato Sintase/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/genética , Neoplasias Colorretais/mortalidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Via Transcriptase Reversa
10.
Am J Psychiatry ; 155(10): 1384-91, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9766770

RESUMO

OBJECTIVE: Magnetic resonance imaging (MRI) studies of schizophrenic patients have revealed structural brain abnormalities, with low volumes of gray matter in the left posterior superior temporal gyrus and in medial temporal lobe structures. However, the specificity to schizophrenia and the roles of chronic morbidity and neuroleptic treatment in these abnormalities remain unclear. METHOD: Magnetic resonance (1.5-T) scans were obtained from 33 patients with first-episode psychosis and 18 age-matched normal comparison subjects, all right-handed. Sixteen of the patients were diagnosed with affective disorder and 17 with schizophrenia. RESULTS: Quantitative volumetric analysis showed that the patients with first-episode schizophrenia had significantly smaller gray matter volume in the left posterior superior temporal gyrus than did the patients with first-episode affective psychosis or the comparison subjects, with a significant left-less-than-right asymmetry. The schizophrenic patients also showed a smaller gray matter volume of the left posterior amygdala-hippocampal complex than the comparison subjects. Both the patients with schizophrenia and those with affective psychosis had significant left-less-than-right asymmetry of the posterior amygdala-hippocampal complex. CONCLUSIONS: These findings suggest that temporal lobe abnormalities are present at the first hospitalization for schizophrenia and that low volume of the left posterior superior temporal gyrus gray matter is specific to schizophrenia compared with affective disorder.


Assuntos
Transtornos Psicóticos Afetivos/diagnóstico , Lateralidade Funcional , Imageamento por Ressonância Magnética , Esquizofrenia/diagnóstico , Lobo Temporal/anatomia & histologia , Adolescente , Adulto , Tonsila do Cerebelo/anatomia & histologia , Diagnóstico Diferencial , Feminino , Hipocampo/anatomia & histologia , Hospitalização , Humanos , Masculino
11.
World J Surg ; 21(6): 653-8; discussion 659, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9230666

RESUMO

Surgical treatment of familial adenomatous polyposis (FAP) is still controversial. From 1984 we carried out a prospective evaluation of total colectomy with ileorectal anastomosis (IRA) and restorative proctocolectomy with ileal pouch-anal anastomosis (IPAA) to determine differences in postoperative complications, functional results, occurrence of desmoids, and recurrence of polyps in the rectal stump. IRA was performed below the peritoneal reflection and was indicated in the absence of rectal cancer and in the presence of fewer than 10 polyps or minute polyposis in the last 10 cm of the rectal mucosa. IRA patients underwent a regular endoscopic follow-up and prolonged sulindac administration (100 mg twice daily). When criteria for IRA were absent, IPAA was performed adopting a manual anastomosis at the pectinate line. Fourteen patients were operated with IRA and 24 with IPAA. There was no difference in sex and age between the two groups of patients. The number of rectal polyps was significantly different in the two groups. Immediate postoperative complications were observed in only five IPAA patients, three of whom (12%) required reoperation. Late postoperative complications occurred more frequently in IRA patients (14%) than in IPAA patients (4%). Desmoids developed in both groups (five in the IRA group and four in IPAA group). The number of bowel movements was similar in both groups, but 25% of IPAA patients complained of nocturnal fecal soiling. Fulguration or polypectomy for recurrent polyps was necessary in all but two IRA patients at follow-up. The rectal stump was easily eradicated by polyps in all but four patients with minute polyps at surgery. In the latter patients a diffuse or carpeting rectal polyposis occurred. IPAA can give optimum control of colorectal polyposis in FAP patients with an acceptable incidence of postoperative complications and satisfactory functional results. This type of surgical procedure is indicated in most FAP patients, and IRA should be reserved for patients without polyps or with fewer than 10 polyps in the rectal stump; otherwise growth of polyps cannot be adequately controlled.


Assuntos
Polipose Adenomatosa do Colo/cirurgia , Proctocolectomia Restauradora , Reto/cirurgia , Adolescente , Adulto , Anastomose Cirúrgica , Criança , Colectomia , Feminino , Humanos , Íleo/cirurgia , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Estudos Prospectivos
12.
Int J Colorectal Dis ; 12(5): 261-6, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9401838

RESUMO

UNLABELLED: An alternative technique of restorative proctocolectomy, by means of straight ileoanal anastomosis with multiple myotomies (SIAM) of the terminal ileum in 15 patients, nine with familial adenomatous polyposis (FAP) and six with ulcerative colitis (UC) is reported. SURGICAL TECHNIQUE: Eight to ten longitudinal myotomies (3-4 cm long, on three different circumferential sites) were performed on the terminal ileum for a total length of 12-14 cm. CLINICAL RESULTS: At a mean follow up of 44 months (range 3-84 months) from the closure of the ileostomy, daytime continence was achieved in all the patients; stool frequency per 24 hours (+/- SD) was 4.1 +/- 1.8 for FAP patients and 5.8 +/- 1.7 for UC patients; nocturnal defecation was 1.0 +/- 0.5 and 1.2 +/- 0.8 for FAP and UC patients respectively; frequent nocturnal soiling was present in 2/5 of UC patients, and in 3/9 of FAP patients. SIAM failed in one UC patient that was converted to an ileoanal reservoir because of poor functional result. Signs of ileal mucosal inflammation were never observed at endoscopic examination. Histopathological assessment showed no evidence of acute terminal ileitis. MANOMETRIC FINDINGS: A significant postoperative reduction in anal resting pressure was observed after SIAM. Neither the absence of anal inhibitory reflex nor the presence of high pressure waves generated in the terminal ileum during air insufflation were related to the presence of soiling. The closure of the loop ileostomy was followed by an increased capacity and distensibility of the terminal ileum. Values of neorectal compliance were similar in FAP and UC patients although FAP patients were able to reach higher values of maximum tolerated volume and pressure. CONCLUSIONS: 1) SIAM can be an alternative to pelvic pouch in patients who have undergone restorative proctocolectomy when the construction of the pouch is not feasible. 2) The functional result observed after SIAM has been shown to be similar to that observed after pouch construction.


Assuntos
Pólipos Adenomatosos/cirurgia , Canal Anal/cirurgia , Colite Ulcerativa/cirurgia , Íleo/cirurgia , Músculo Liso/cirurgia , Proctocolectomia Restauradora/métodos , Adolescente , Adulto , Canal Anal/fisiologia , Anastomose Cirúrgica/métodos , Criança , Feminino , Seguimentos , Humanos , Íleo/fisiologia , Masculino , Manometria , Pessoa de Meia-Idade , Músculo Liso/fisiologia
13.
Minerva Chir ; 51(10): 765-72, 1996 Oct.
Artigo em Italiano | MEDLINE | ID: mdl-9082203

RESUMO

Only recently, in our laboratory of experimental surgery, we started with a protocol for orthotopic liver transplantation (OLT) in a pig model. This was felt as mandatory for experimental purposes as well as for future clinical applications at our center. We report herein our own experience with 41 OLTx. Intraoperative "lethal" complications occurred in up to 32% (14/41) whereas postoperative complications occurred in the remainders at different intervals of time with a maximum survival of 30 days. No attention was paid to prevent rejection-infection episodes. The main cause of death was the primary non-function (PNF) or dis-function (PDF) manifested either intra or postoperatively in 16 out the 41 OLTx (39%). Intraoperative technical errors accounted for up to 9% (4/41 OLTx). Acute hemorrhage gastritis and gastric perforations occurred postoperatively in 6 animals (14%) and represent one of the peculiar aspects of OLT in pig model.


Assuntos
Transplante de Fígado/métodos , Animais , Complicações Intraoperatórias/epidemiologia , Complicações Intraoperatórias/etiologia , Transplante de Fígado/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Taxa de Sobrevida , Suínos
14.
J Neurophysiol ; 76(3): 1439-56, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8890265

RESUMO

1. The lateral intraparietal area (area LIP) of the monkey's posterior parietal cortex (PPC) contains neurons that are active during saccadic eye movements. These neurons' activity includes visual and saccade-related components. These responses are spatially tuned and the location of a neuron's visual receptive field (RF) relative to the fovea generally overlaps its preferred saccade amplitude and direction (i.e., its motor field, MF). When a delay is imposed between the presentation of a visual stimulus and a saccade made to its location (memory saccade task), many LIP neurons maintain elevated activity during the delay (memory activity, M), which appears to encode the metrics of the next intended saccadic eye movements. Recent studies have alternatively suggested that LIP neurons encode the locations of visual stimuli regardless of where the animal intends to look. We examined whether the M activity of LIP neurons specifically encodes movement intention or the locations of recent visual stimuli, or a combination of both. In the accompanying study, we investigated whether the intended-movement activity reflects changes in motor plan. 2. We trained monkeys (Macaca mulatta) to memorize the locations of two visual stimuli and plan a sequence of two saccades, one to each remembered target, as we recorded the activity of single LIP neurons. Two targets were flashed briefly while the monkey maintained fixation; after a delay the fixation point was extinguished, and the monkey made two saccades in sequence to each target's remembered location, in the order in which the targets were presented. This "delayed double saccade" (DDS) paradigm allowed us to dissociate the location of visual stimulation from the direction of the planned saccade and thus distinguish neuronal activity related to the target's location from activity related to the saccade plan. By imposing a delay, we eliminated the confounding effect of any phasic responses coincident with the appearance of the stimulus and with the saccade. 3. We arranged the two visual stimuli so that in one set of conditions at least the first one was in the neuron's visual RF, and thus the first saccade was in the neuron's motor field (MF). M activity should be high in these conditions according to both the sensory memory and motor plan hypotheses. In another set of conditions, the second stimulus appeared in the RF but the first one was presented outside the RF, instructing the monkey to plan the first saccade away from the neuron's MF. If the M activity encodes the motor plan, it should be low in these conditions, reflecting the plan for the first saccade (away from the MF). If it is a sensory trace of the stimulus' location, it should be high, reflecting stimulation of the RF by the second target. 4. We tested 49 LIP neurons (in 3 hemispheres of 2 monkeys) with M activity on the DDS task. Of these, 38 (77%) had M activity related to the next intended saccade. They were active in the delay period, as expected, if the first saccade was in their preferred direction. They were less active or silent if the next saccade was not in their preferred direction, even when the second stimulus appeared in their RF. 5. The M activity of 8 (16%) of the remaining neurons specifically encoded the location of the most recent visual stimulus. Their firing rate during the delay reflected stimulation of the RF independently of the saccade being planned. The remaining 3 neurons had M activity that did not consistently encode either the next saccade or the stimulus' location. 6. We also recorded the activity of a subset of neurons (n = 38) in a condition in which no stimulus appeared in a neuron's RF, but the second saccade was in the neuron's MF. In this case the majority of neurons tested (23/38, 60%) became active in the period between the first and second saccade, even if neither stimulus had appeared in their RF. Moreover, this activity appeared only after the first saccade had started in all but two of


Assuntos
Memória/fisiologia , Neurônios/fisiologia , Lobo Parietal/fisiologia , Movimentos Sacádicos/fisiologia , Sensação/fisiologia , Animais , Condicionamento Operante/fisiologia , Eletrofisiologia , Fixação Ocular/fisiologia , Lateralidade Funcional/fisiologia , Sistemas de Informação , Macaca mulatta , Masculino , Neurônios Motores/fisiologia , Lobo Parietal/citologia , Estimulação Luminosa , Período Refratário Eletrofisiológico/fisiologia
15.
J Neurophysiol ; 76(3): 1457-64, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8890266

RESUMO

1. In the companion paper we reported that the predominant signal of the population of neurons in the lateral intraparietal area (area LIP) of the monkey's posterior parietal cortex (PPC) encode the next intended saccadic eye movement during the delay period of a memory-saccade task. This result predicts that, should be monkey change his intention of what the next saccade will be, LIP activity should change accordingly to reflect the new plan. We tested this prediction by training monkeys to change their saccadic plan on command and recording the activity of LIP neurons across plan changes. 2. We trained rhesus monkeys (Macaca mulatta) to maintain fixation on a light spot as long as this spot remained on. During this period we briefly presented one, two, or three peripheral visual stimuli in sequence, each followed by a delay (memory period, M). After the final delay the fixation spot was extinguished, and the monkey had to quickly make a saccade to the location of the last target to have appeared. The monkey could not predict which stimuli, nor how many, would appear on each trial. He thus had to plan a saccade to each stimulus as it appeared and change his saccade plan whenever a stimulus appeared at a different location. 3. We recorded the M period activity of 81 area LIP neurons (from 3 hemispheres of 2 monkeys) in this task. We predicted that, if a neuron's activity reflected the monkey's planned saccade, its activity should be high while the monkey planned a saccade in the neuron's motor field (MF), and low while the planned saccade was in the opposite direction. The activity of most of the neurons in our sample changed in accordance with our hypothesis as the monkey's planned saccade changed. 4. In one condition the monkey was instructed by visual stimuli to change his plan from a saccade in the neuron's preferred direction to a saccade planned in the opposite direction. In this condition activity decreased significantly (P < 0.05) in 65 (80%) of 81 neurons tested. These neurons' activity changed to reflect the new saccade plan even though the cue for this change was not presented in their RF. 5. As a control we randomly interleaved, among trials requiring a plan change, trials in which the monkey had to formulate two consecutive plans to make a saccade in the neuron's preferred direction. The activity remained unchanged (P < 0.05) in 22 of 31 neurons tested (79%), indicating that the neurons continued to encode the same saccade plan. 6. In a variant of the task, the cue to the location of the required saccade was either a light spot or a noise burst from a loudspeaker. Of 22 neurons tested in this task, 16 (73%) showed activity changes consistent with plan changes cued by visual or auditory stimuli. 7. Alterations in the monkey's intentions, even in the absence of overt behavior, are manifested in altered LIP activity. These activity changes could be induced whether visual or auditory cues were used to indicate the required plan changes. Most LIP neurons thus do not encode only the locations of visual stimuli, but also the intention to direct gaze to specific locations, independently of whether a gaze shift actually occurs.


Assuntos
Memória/fisiologia , Neurônios/fisiologia , Lobo Parietal/fisiologia , Movimentos Sacádicos/fisiologia , Estimulação Acústica , Animais , Condicionamento Operante/fisiologia , Sinais (Psicologia) , Eletrofisiologia , Fixação Ocular/fisiologia , Macaca mulatta , Masculino , Neurônios Motores/fisiologia , Lobo Parietal/citologia , Estimulação Luminosa
16.
J Neurophysiol ; 76(3): 2071-6, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8890315

RESUMO

1. The lateral intraparietal area (LIP) of the posterior parietal cortex lies within the dorsal cortical stream for spatial vision and processes visual information to plan saccadic eye movements. We investigated how LIP neurons respond when a monkey makes saccades to the remembered location of sound sources in the absence of visual stimulation. 2. Forty-three (36%) of the 118 neurons sampled showed significant auditory triggered activity during the memory period. This figure is similar to the proportion of cells showing visually triggered memory activity. 3. Of the cells showing auditory memory activity, 44% discharged in an eye-centered manner, similar to the way in which LIP cells discharge for visually initiated saccades. Another 33% responded in head-centered coordinates, and the remaining 23% had responses intermediate between the two reference frames. 4. For a substantial number of cells in all three categories, the magnitude of the response was modulated by eye position. Similar orbital "gain fields" had been shown previously for visual saccades. 5. We propose that area LIP is either at the origin of, or participates in, the transformation of auditory signals for oculomotor purposes, and that orbital gains on the discharge are part of this process. 6. Finally, we suggest that, by the level of area LIP, cells are concerned with the abstract quality of where a stimulus is in space, independent of the exact nature of the stimulus.


Assuntos
Movimentos Oculares/fisiologia , Movimentos da Cabeça/fisiologia , Memória/fisiologia , Lobo Parietal/fisiologia , Localização de Som/fisiologia , Estimulação Acústica , Animais , Estimulação Elétrica , Macaca mulatta , Neurônios/fisiologia , Lobo Parietal/citologia , Movimentos Sacádicos/fisiologia
17.
J Neurophysiol ; 75(3): 1233-41, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8867131

RESUMO

1. The lateral intraparietal area (area LIP) of the macaque's posterior parietal cortex (PPC) lies in the dorsal stream of extrastriate visual areas. It receives extensive visual inputs and sends outputs to several eye movement centers. It contains neurons with visual and saccade-related responses suggesting a role of area LIP in programming saccadic eye movements to visual targets. Because primates can also orient to nonvisual stimuli, we investigated whether LIP neurons process stimuli of other modalities besides the visual one by comparing their activity in auditory and visual saccade tasks. 2. We recorded the activity of single neurons of Macaca mulatta monkeys while they performed memory saccades to acoustic and visual targets. We analyzed the activity during stimulus presentation (stimulus period, S) and during the delay (memory period, M) between stimulus presentation and the saccade to its remembered location. 3. Among 80 area LIP neurons tested, we found 44 that had S period and/or M period responses following presentation of the auditory stimulus. Most of these responses were spatially tuned, i.e., selective for the left or right stimulus location (27 of 29 S responses; 25 of 29 M responses). 4. The majority of neurons with responses in the auditory memory saccade task also responded in the visual version of the task. Eighty-nine percent (24/27) were clearly bimodal in the S period, and 88% (23/26) were bimodal in the M period. 5. Almost all the neurons with spatially tuned auditory responses that were bimodal were also spatially tuned in their visual responses (20/22 for S responses; 18/19 for M responses). The spatial tuning for the two modalities was the same in 85% (17/20) of the tested neurons for the S responses, and in 83% (15/18) of the tested neurons for the M responses. 6. Area LIP contains a population of neurons that respond to both visual and auditory stimuli. This result is consistent with our finding that the memory activity of many LIP cells encodes the next planned saccade. If cells are coding planned movements, they should be active independently of the sensory modality of the target for the movement, as was the case for most of the neurons described in the present study.


Assuntos
Comportamento Animal/fisiologia , Memória/fisiologia , Neurônios/fisiologia , Lobo Parietal/fisiologia , Estimulação Acústica , Animais , Contagem de Células , Cricetinae , Macaca , Masculino , Estimulação Luminosa , Tempo de Reação/fisiologia
18.
Anticancer Res ; 15(5B): 2247-53, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8572632

RESUMO

The aim of this study was to evaluate the relationship between DNA ploidy, proliferative activity and other prognostic factors and the survival of patients with colorectal cancer. 45 patients were prospectively investigated for 6 years. Fresh multiple samples for flow cytometric analysis of DNA content were collected during surgical resection of primary tumor. A 42% frequency of aneuploidy was observed with a median DNA index value of 1.54. The proliferative activity (%S+G2M cells) was higher in the aneuploid cell sub-population (28.6%) compared to the diploid counterpart (22.7%)(p = 0.05). No significant relationship between DNA ploidy and tumor site, Dukes' stage, histological type, grading age or sex was observed. No correlation between DNA ploidy and survival was demonstrated, including in the analysis of patient subsets according to stage. No additive prognostic information was obtained from a breakdown analysis as a function of DI values, percentages of aneuploid cells and proliferative activity. This study suggests that flow cytometric content analysis lacks prognostic value in colorectal carcinoma.


Assuntos
Neoplasias Colorretais/patologia , DNA de Neoplasias/análise , Citometria de Fluxo , Adulto , Idoso , Idoso de 80 Anos ou mais , Aneuploidia , Divisão Celular , Neoplasias Colorretais/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico
19.
Ann Ital Chir ; 64(6): 675-8; discussion 679, 1993.
Artigo em Italiano | MEDLINE | ID: mdl-8080158

RESUMO

Restorative proctocolectomy with ileal-anal anastomosis can induce a duodenal stenosis due to the compression between superior mesenteric artery (SMA) and aorta when the ileum is pulled-down to the anus stretching the SMA. This situation may require prolonged nasogastric intubation or even surgery. In our experience this occurred in 10% of pts. Aiming to avoid this complication we have performed an intestinal derotation just before ileal-anal anastomosis abolishing any possibility of duodenal compression. Comparing this latter group of patients to those who didn't receive intestinal derotation, we observed a significant reduction of nasogastric tube drainage and of the nasogastric intubation time. We think that intestinal derotation could be effective in preventing SMA syndrome after restorative proctocolectomy and ileal-anal anastomosis.


Assuntos
Complicações Pós-Operatórias/prevenção & controle , Proctocolectomia Restauradora/efeitos adversos , Síndrome da Artéria Mesentérica Superior/prevenção & controle , Adolescente , Adulto , Canal Anal/cirurgia , Anastomose Cirúrgica/métodos , Feminino , Humanos , Íleo/cirurgia , Masculino , Pessoa de Meia-Idade , Proctocolectomia Restauradora/métodos
20.
Curr Opin Neurobiol ; 2(6): 840-6, 1992 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1477549

RESUMO

It has long been appreciated that the posterior parietal cortex plays a role in the processing of saccadic eye movements. Only recently has it been discovered that a small cortical area, the lateral intraparietal area, within this much larger area appears to be specialized for saccadic eye movements. Unlike other cortical areas in the posterior parietal cortex, the lateral intraparietal area has strong anatomical connections to other saccade centers, and its cells have saccade-related responses that begin before the saccades. The lateral intraparietal area appears to be neither a strictly visual nor strictly motor structure; rather it performs visuomotor integration functions including determining the spatial location of saccade targets and forming plans to make eye movements.


Assuntos
Lobo Parietal/fisiologia , Movimentos Sacádicos/fisiologia , Animais , Mapeamento Encefálico , Estimulação Elétrica , Haplorrinos/fisiologia , Humanos , Memória/fisiologia , Lobo Parietal/anatomia & histologia
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