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1.
Childs Nerv Syst ; 38(8): 1599-1603, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35006339

RESUMO

There are no specific guidelines regarding best treatment for focal, distant metastasis in ependymoma in the context of a well-controlled primary site. A combination using maximal safe resection and adjuvant radiotherapy is usually advised. As wound healing might be hindered by repeated radiotherapy, and delay future radiation treatment if needed, there is a growing interest in less invasive surgeries to reduce post-operative pain and wound healing complications. Those approaches have been extensively used and studied in adult but never in the pediatric population. Here, we present a pediatric case of a 12-year-old boy known for a posterior fossa ependymoma completely resected 18 months earlier who presented with a dual lumbosacral intradural ependymoma metastasis. A single-stage complete resection was achieved using a fixed tubular retractor with no complication. Post-operative course was favorable with rapid healing and discharge, minimal post-operative pain, and a rapid return to normal activities. Re-irradiation could be performed 2 weeks later without any problem. To our knowledge, this is the first report of the use of minimally invasive techniques to achieve complete resection of dual intradural metastasis of an ependymoma in the pediatric population. We demonstrate its feasibility and safety as well as its advantages.


Assuntos
Ependimoma , Neoplasias da Medula Espinal , Neoplasias da Coluna Vertebral , Criança , Ependimoma/patologia , Humanos , Masculino , Dor Pós-Operatória , Neoplasias da Medula Espinal/diagnóstico por imagem , Neoplasias da Medula Espinal/patologia , Neoplasias da Medula Espinal/cirurgia , Neoplasias da Coluna Vertebral/diagnóstico por imagem , Neoplasias da Coluna Vertebral/radioterapia , Neoplasias da Coluna Vertebral/cirurgia , Resultado do Tratamento
2.
Clin Oral Investig ; 26(3): 2503-2511, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34677695

RESUMO

OBJECTIVES: Mouth breathing is a key feature of obstructive sleep apnea (OSA). The current study evaluated dental, salivary and orthodontic characteristics of children with OSA, and compared them to those of children without OSA. MATERIALS AND METHODS: Twenty-two children (mean age 5.3 years, 13 males) with OSA and 21 children without OSA who served as a control group (mean age 6.8 years, 11 males) underwent dental examinations. The OSA group was classified according to the apnea-hypopnea Index. Clinical examination included plaque index, gingival index, caries status, pH at 7 oral sites, salivary carries bacterial counts and inflammatory cytokine levels. Orthodontics measurements were calculated as the percentage of children with values in the normal range, in each group. RESULTS: The mean values of the decayed, missing and filled teeth (DMFT)/dmft index, the gingival index and the plaque index were higher in the OSA than the control group. Salivary Mutans streptococci and lactobacilli counts were significantly higher in the OSA than the control group; as were pH values in the hard and soft palate, and in the posterior and middle tongue. Significantly lower values were observed in the OSA than the control group for most of the orthodontic variables examined. Similarly, stratification of AHI according to severity shows the lowest values among those with mild OSA, and the highest among those with severe AHI. CONCLUSIONS: Compared to a control group, mouth breathing children with obstructive sleep apnea had differences in oral microbiota, greater acidity and poorer dental status. CLINICAL RELEVANCE: Clinicians should be aware of the various oral disturbances that may accompany OSA, and implement preventive measures.


Assuntos
Apneia Obstrutiva do Sono , Criança , Pré-Escolar , Humanos , Concentração de Íons de Hidrogênio , Masculino , Palato Mole , Índice Periodontal , Polissonografia
3.
Rev Neurol (Paris) ; 165(10): 750-4, 2009 Oct.
Artigo em Francês | MEDLINE | ID: mdl-19733375

RESUMO

In this article, we review recently published data on the role of the insula in refractory partial epilepsy and summarize our own experience in the investigation and treatment of this entity. Case studies and evoked responses obtained from insular cortical stimulation reveal a wide array of clinical manifestations which may mimic temporal, frontal or parietal lobe seizures. Clinicians should hence lower their threshold to sample the insula with intracerebral electrodes. Lack of recognition of insular seizures may explain part of epilepsy surgery failures. Advances in microneurosurgery open the way to safer insular resection.


Assuntos
Epilepsia do Lobo Temporal/diagnóstico , Eletroencefalografia , Epilepsia do Lobo Temporal/fisiopatologia , Epilepsia do Lobo Temporal/cirurgia , Humanos , Imageamento por Ressonância Magnética , Procedimentos Neurocirúrgicos , Quebeque
4.
AJNR Am J Neuroradiol ; 40(12): 2066-2072, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31672836

RESUMO

BACKGROUND AND PURPOSE: Moyamoya disease is a chronic neurovascular steno-occlusive disease of the internal carotid artery and its main branches, associated with the development of compensatory vascular collaterals. Literature is lacking about the precise description of these compensatory vascular systems. Usually, the posterior circulation is less affected, and its vascular flow could compensate the hypoperfusion of the ICA territories. The aim of this study was to describe these natural connections between the posterior cerebral artery and the anterior cerebral artery necessary to compensate the lack of perfusion of the anterior cerebral artery territories in the Moyamoya population. MATERIALS AND METHODS: All patients treated for Moyamoya disease from 2004 to 2018 in 4 neurosurgical centers with available cerebral digital subtraction angiography were included. Forty patients (80 hemispheres) with the diagnosis of Moyamoya disease were evaluated. The presence of anastomoses between the posterior cerebral artery and the anterior cerebral artery was found in 31 hemispheres (38.7%). RESULTS: Among these 31 hemispheres presenting with posterior cerebral artery-anterior cerebral artery anastomoses, the most frequently encountered collaterals were branches from the posterior callosal artery (20%) and the posterior choroidal arteries (20%). Another possible connection found was pio-pial anastomosis between cortical branches of the posterior cerebral artery and the anterior cerebral artery (15%). We also proposed a 4-grade classification based on the competence of these anastomoses to supply retrogradely the territories of the anterior cerebral artery. CONCLUSIONS: We found 3 different types of anastomoses between the anterior and posterior circulations, with different abilities to compensate the anterior circulation. Their development depends on the perfusion needs of the territories of the anterior cerebral artery and can provide the retrograde refilling of the anterior cerebral artery branches.


Assuntos
Angiografia Cerebral/métodos , Artérias Cerebrais/anatomia & histologia , Circulação Cerebrovascular/fisiologia , Circulação Colateral/fisiologia , Doença de Moyamoya/patologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
5.
J Vet Pharmacol Ther ; 31(4): 359-67, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18638297

RESUMO

Lidocaine patches have been used to provide local analgesia in dogs and cats. We conducted this study to assess the systemic and local absorption of lidocaine from topical patches in cats. Eight 2-year-old cats received either intravenous lidocaine at 2 mg/kg or one 700 mg lidocaine patch placed on the lateral thorax for 72 h, in a cross-over randomized repeated measures design. Plasma was collected at specific times and the skin was biopsied at the time of patch removal for the quantitative analysis of lidocaine and its major metabolite, monoethylglycinexylidide (MEGX), by gas chromatography with mass spectrometry. Percent absorption time plots for systemic lidocaine appearance were constructed using the Loo-Riegelman method. Approximately, constant rate absorption was observed from 12-72 h after patch application at a mean +/- SD rate of 109 +/- 49 microg/kg/h, resulting in steady-state lidocaine plasma concentrations of 0.083 +/- 0.032 microg/mL and MEGX concentrations of 0.012 +/- 0.009 microg/mL. Overall bioavailability of transdermal lidocaine was 6.3 +/- 2.7%, and only 56 +/- 29% of the total lidocaine dose delivered by the patch reached systemic circulation. Skin lidocaine concentrations were much higher than plasma concentrations, at 211 +/- 113 microg/g in the thoracic skin beneath the patch and 2.2 +/- 0.6 microg/g in the contralateral thoracic skin without the patch. As both lidocaine and MEGX were recovered from contralateral skin, it is likely that lidocaine accumulated in the skin from low systemic concentrations of circulating lidocaine over the 72-h period of patch application. Plasma lidocaine concentrations remained well below systemically toxic concentrations, and no obvious clinical side effects were observed in any of the cats. The low systemic absorption rate coupled with high local lidocaine concentrations on the skin support the safe use of lidocaine patches in cats.


Assuntos
Anestésicos Locais/farmacocinética , Lidocaína/farmacocinética , Absorção , Administração Cutânea , Anestésicos Locais/administração & dosagem , Anestésicos Locais/sangue , Animais , Área Sob a Curva , Disponibilidade Biológica , Gatos , Estudos Cross-Over , Feminino , Meia-Vida , Injeções Intravenosas , Lidocaína/administração & dosagem , Lidocaína/sangue , Masculino , Taxa de Depuração Metabólica
6.
AJNR Am J Neuroradiol ; 39(6): 1121-1126, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29650781

RESUMO

BACKGROUND AND PURPOSE: Moyamoya disease is a progressive neurovascular pathology defined by steno-occlusive disease of the distal internal carotid artery and associated with the development of compensatory vascular collaterals. The etiology and exact anatomy of vascular collaterals have not been extensively studied. The aim of this study was to describe the anatomy of collaterals developed between the ophthalmic artery and the anterior cerebral artery in a Moyamoya population. MATERIALS AND METHODS: All patients treated for Moyamoya disease from 2004 to 2016 in 4 neurosurgical centers with available cerebral digital subtraction angiography were included. Sixty-three cases were evaluated, and only 38 met the inclusion criteria. Two patients had a unilateral cervical internal carotid occlusion that limited analysis of ophthalmic artery collaterals to one hemisphere. This study is consequently based on the analysis of 74 cerebral hemispheres. RESULTS: Thirty-eight patients fulfilled the inclusion criteria. The most frequently encountered anastomosis between the ophthalmic artery and cerebral artery was a branch of the anterior ethmoidal artery (31.1%, 23 hemispheres). In case of proximal stenosis of the anterior cerebral artery, a collateral from the posterior ethmoidal artery could be visualized (16 hemispheres, 21.6%). One case (1.4%) of anastomosis between the lacrimal artery and the middle meningeal artery that permitted the vascularization of a middle cerebral artery territory was also noted. CONCLUSIONS: Collaterals from the ophthalmic artery are frequent in Moyamoya disease. Their development depends on the perfusion needs of the anterior cerebral artery territories. Three other systems of compensation could be present (callosal circle, leptomeningeal anastomosis, and duro-pial anastomoses).


Assuntos
Circulação Colateral , Doença de Moyamoya/patologia , Artéria Oftálmica/patologia , Angiografia Cerebral , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
7.
Med Hypotheses ; 102: 102-105, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28478813

RESUMO

Cerebral salt wasting syndrome (CSWS) is a well-described consequence of several neurological disorders. Although the exact etiology of CSWS is still not completely elucidated, it is believed that the hypothalamus plays a pivotal role in the genesis of this disorder. We report for the first time 3 cases of CSWS occurring during the post-operative course following surgical resection of exophytic bulbar pilocytic astrocytomas in children. Since these 3 cases shared in common a medial implication of the medulla, we suggest that specific interconnectivity between the dorso-medial portion of the medulla oblongata and the hypothalamus might thus represent an anatomical pathway of interest in the pathogenesis of CSWS. Our findings suggest that the resection of medially located exophytic bulbar tumors might constitutes a risk factor in the development of CSWS. Particular care should thus be carried towards the prompt detection and treatment of CSWS in the post-operative courses of exophytic bulbar tumors.


Assuntos
Astrocitoma/fisiopatologia , Astrocitoma/cirurgia , Neoplasias Encefálicas/fisiopatologia , Neoplasias Encefálicas/cirurgia , Hipotálamo/fisiopatologia , Síndrome de Secreção Inadequada de HAD/fisiopatologia , Bulbo/fisiopatologia , Animais , Pré-Escolar , Feminino , Humanos , Síndrome de Secreção Inadequada de HAD/etiologia , Lactente , Masculino , Procedimentos Neurocirúrgicos/efeitos adversos
8.
Orthop Traumatol Surg Res ; 103(2): 295-299, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28089666

RESUMO

STUDY DESIGN: Technical description and single institution retrospective case series. OBJECTIVE: Evaluate technical feasibility and evaluate complications of mini-open retroperitoneal oblique lumbar interbody fusion (OLIF) at the L5-S1 level. SUMMARY OF BACKGROUND: The mini-open retroperitoneal oblique lumbar interbody fusion (OLIF) approach was first described in 2012 as a surgical approach to achieve spinal fusion while limiting invasiveness of the exposure to the anterior lumbar spine. Surgeons who use this approach, along with those who described it in cadaveric studies describe it as a feasible approach in targeting the L2 down to the L5 level and recommend alternative approaches to the L5-S1 level due to the vascular challenges and possible complications. METHODS: Technical description and single institution case series of patients treated with the OLIF between 2013 and 2015 at the L5-S1 level. The previously described surgical approach was modified by identifying and ligating the iliolumbar vein before retracting the iliac artery and vein anteriorly instead of passing between the vessels. RESULTS: Six patients (3 males, 3 females, mean age 62 years) were operated between 2013 and 2015. There were no vascular injuries or peripheral nerve trauma associated with the surgical procedure. Complications associated with the procedure included: cage displacement immediately postoperative requiring re-operation in one patient, transient psoas weakness in one patient, extended hospital stay for pain control in one patient, and transfusion was required in one patient. CONCLUSIONS: Mini-open retroperitoneal oblique lumbar interbody fusion is feasible at the L5-S1 level with limited vascular complications through a technical modification for safe mobilization of the iliac vessels by first ligating the iliolumbar vein.


Assuntos
Discotomia , Vértebras Lombares/cirurgia , Sacro/cirurgia , Fusão Vertebral/métodos , Adulto , Idoso , Estudos de Viabilidade , Feminino , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Debilidade Muscular/etiologia , Dor Pós-Operatória/tratamento farmacológico , Dor Pós-Operatória/etiologia , Período Pós-Operatório , Falha de Prótese/etiologia , Músculos Psoas/fisiopatologia , Reoperação , Espaço Retroperitoneal , Estudos Retrospectivos , Fusão Vertebral/efeitos adversos , Resultado do Tratamento
9.
Neuroscience ; 137(3): 795-805, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16303255

RESUMO

A potentially major factor in the development of Alzheimer's disease is the enhanced production of soluble beta-amyloid peptide fragments amyloid beta peptide(1-40) and amyloid beta peptide(1-42). These amyloid peptides are generated by cleavage of the amyloid-precursor protein and aggregate spontaneously to form amyloid plaques, which are a classical pathological hallmark in Alzheimer's disease. Although the precise mechanisms are unknown, it is widely believed that amyloid peptides initiate the degenerative process, resulting in subsequent cognitive decline. One interaction of amyloid beta peptide that may contribute to an impairment of cognition is its high affinity binding to the alpha 7 nicotinic receptor; a receptor shown to be important for cognition in a number of studies. There is some controversy, however, whether amyloid beta peptide inhibits or activates this receptor. We have cloned and stably expressed the human alpha 7 receptor and investigated its interaction with amyloid beta peptide using patch clamp electrophysiology. Human alpha 7 was activated in a concentration-dependent fashion by nicotine, acetylcholine and choline and potently inhibited by methyllycaconitine citrate. The responses were inwardly rectifying and exhibited rapid activation, desensitization and deactivation. Amyloid beta peptide(1-42) antagonized human alpha7 responses in a partially reversible fashion; no agonist effects of amyloid beta peptide(1-42) were detected. A similar inhibition of mouse alpha 7 was also observed. In addition, we have assessed the function of native alpha 7 receptors in hippocampal slices prepared from transgenic mice that over-express human amyloid. Despite this clear inhibition of recombinant receptors, hippocampal GABAergic interneurones in slices from beta-amyloid over-expressing mice still possess alpha 7 receptor-mediated currents.


Assuntos
Peptídeos beta-Amiloides/biossíntese , Peptídeos beta-Amiloides/genética , Receptores Nicotínicos/fisiologia , Peptídeos beta-Amiloides/fisiologia , Animais , Linhagem Celular , Clonagem Molecular , Estimulação Elétrica , Eletrofisiologia , Hipocampo/citologia , Hipocampo/metabolismo , Humanos , Técnicas In Vitro , Interneurônios/metabolismo , Interneurônios/fisiologia , Camundongos , Camundongos Transgênicos , Nicotina/farmacologia , Agonistas Nicotínicos/farmacologia , Técnicas de Patch-Clamp , Fragmentos de Peptídeos/fisiologia , Receptores Nicotínicos/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Receptor Nicotínico de Acetilcolina alfa7
10.
Int J Clin Pharmacol Ther ; 44(2): 64-70, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16502765

RESUMO

OBJECTIVES: The present study was conducted to assess the effect of food on the bioavailability of fenofibric acid from a new tablet formulation containing fenofibrate nanoparticles. METHODS: In this 3-way crossover study, 45 subjects received in a random order one 145 mg fenofibrate tablet under high-fat fed (HFF), low-fat fed (LFF) or fasting (reference) conditions. Plasma concentrations of fenofibric acid were determined up to 120 hours post-dose. Comparisons were made between test (HFF and LFF) and reference conditions (fasting). RESULTS: Very close values of pharmacokinetic parameters were obtained following the three diffiferent regimens. The 90% confidence intervals (CI) for the ratio of geometric means of HIFF versus fasting condition were (1.018-1.088) for AUCinfinity, (1.020-1.090) for AUCt and (0.963-1.054) for Cmax with point estimate:s of 1.052, 1.054 and 1.007, respectively. The 90% CI for the geometric means of LFF versus fasting condition were (0.978-1.046) for AUGinfinity, (0.981-1.047) for AUCt and (0.964-1.055) for Cmax with point estimates of 1.012, 1.013 and 1.009, respectively. They all fall within the required limits for bioequivalence (0.80-1.25). A slightly prolonged tmax was observed following HFF conditions (4.3 +/- 1.9 hours, versus 3.6 +/- 1.2 hours and 2.3 +/- 0.7 hours under LFF and fasting conditions, respectively), without any effect on mean Cmax. CONCLUSION: The peak and overall exposures from the new 145 mg fenofibrate tablet were not affected by food. Therefore, this new fenofibrate tablet may be taken without regard to the timing of meals.


Assuntos
Fenofibrato/farmacocinética , Interações Alimento-Droga , Alimentos , Hipolipemiantes/farmacocinética , Adolescente , Adulto , Área Sob a Curva , Disponibilidade Biológica , Estudos Cross-Over , Gorduras na Dieta/administração & dosagem , Relação Dose-Resposta a Droga , Jejum/sangue , Feminino , Fenofibrato/administração & dosagem , Fenofibrato/sangue , Humanos , Hipolipemiantes/administração & dosagem , Hipolipemiantes/sangue , Masculino , Nanoestruturas , Valores de Referência , Comprimidos
11.
Neurochirurgie ; 62(5): 258-262, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27615153

RESUMO

BACKGROUND: Vascular lesions of the spinal cord are increasingly recognized. The most common types of these lesions are dural arteriovenous fistulas (AVFs) whereas, extradural AVFs are a very rare type of spinal AVF and can be associated with either extradural or intradural venous reflux. This results in neurological deficits through congestive or compressive myeloradiculopathy. These lesions must be treated to allow stabilization or improvement of neurologic status, either by endovascular therapy or microsurgical interruption. However, because some patients are not amenable to endovascular treatment, surgery is often warranted, which usually involves hemi- or bilateral laminectomy following a midline approach with bilateral muscle stripping. The main drawback of this procedure is directly related to the morbidity of the approach. Although, minimally invasive approaches are likely to overcome this drawback, there is a lack of reported experience supporting their use for treating spinal dural AVFs. CASE PRESENTATION: Two patients, aged 62 and 79 years old, presented with rapidly progressive myelopathy characterized by paraparesis and sphincter disturbance. Spinal magnetic resonance imaging showed spinal cord oedema with perimedullary flow voids in both cases. Digital subtraction angiography revealed extradural AVFs associated with perimedullary venous reflux. Endovascular therapy was not feasible. Both patients were treated with microsurgical interruption of the intradural vein through a non-expendable retractor. Complete exclusion was confirmed on postoperative angiography, resulting in resolution of spinal cord edema and improved neurological functional status at 2-year follow-up. CONCLUSION: The minimally invasive surgical treatment of spinal AVFs with epidural venous reflux is safe and effective. This approach is a valuable alternative to endovascular therapy and the standard open microsurgical approach.


Assuntos
Malformações Vasculares do Sistema Nervoso Central/cirurgia , Dura-Máter/cirurgia , Procedimentos Cirúrgicos Minimamente Invasivos , Idoso , Malformações Vasculares do Sistema Nervoso Central/patologia , Humanos , Laminectomia/métodos , Imageamento por Ressonância Magnética/métodos , Microcirurgia/métodos , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Medula Espinal/patologia , Medula Espinal/cirurgia , Doenças da Medula Espinal/cirurgia , Veias/cirurgia
12.
Endocrinology ; 142(9): 3809-16, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11517157

RESUMO

The purpose of the present study was to examine the possible involvement of caspase-3 and caspase-activated deoxyribonuclease in rat testicular germ cell apoptosis resulting from reduced intratesticular testosterone concentration. Adult Sprague Dawley rats received LH-suppressive testosterone- and estradiol-filled SILASTIC capsules of 2.5 and 0.1 cm, respectively, a regimen known to rapidly reduce testosterone production by the testes and to produce azoospermia within 8 wk. Germ cell internucleosomal DNA cleavage increased compared with control levels by 1 wk postimplantation and increased further through 4 wk. In situ terminal deoxynucleotidyltransferase-mediated deoxy-UTP nick end labeling revealed that spermatocytes represented the predominant apoptotic cell type. Modest immunoreactivity for active caspase-3 was localized to the cytoplasm or perinuclear region of the germ cells of control testes. After testosterone and estradiol administration, however, intense staining for caspase-3 was localized to the nuclei of spermatocytes. Western blotting revealed significantly increased caspase-3 cleavage (activation) in nuclei isolated from germ cells after rats were administered testosterone and estradiol. Cleavage of the caspase-3 substrate protein, poly(ADP-ribose) polymerase, was seen after testosterone and estradiol treatment. Additionally, the caspase-activated deoxyribonuclease protein content was significantly increased in germ cells after rats were administered testosterone and estradiol, and caspase-activated deoxyribonuclease immunoreactivity was localized to the nuclei of apoptotic spermatocytes. Taken together, these results indicate that germ cell apoptosis resulting from a reduced intratesticular testosterone concentration is caspase-3 activation dependent and suggest that the translocation of active caspase-3 and caspase-activated deoxyribonuclease to the nucleus may be involved in the induction of germ cell apoptosis.


Assuntos
Apoptose/fisiologia , Caspases/metabolismo , Desoxirribonucleases/metabolismo , Espermatozoides/fisiologia , Testosterona/antagonistas & inibidores , Animais , Caspase 3 , Ativação Enzimática/fisiologia , Masculino , Tamanho do Órgão/fisiologia , Poli(ADP-Ribose) Polimerases/química , Ratos , Ratos Sprague-Dawley , Testículo/anatomia & histologia , Testículo/fisiologia
13.
Proc Biol Sci ; 267(1450): 1301-9, 2000 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-10972124

RESUMO

Recent analyses have suggested that extinction and origination rates exhibit long-range correlations, implying that the fossil record may be controlled by self-organized criticality or other scale-free internal dynamics of the biosphere. Here we directly test for correlations in the fossil record by calculating the autocorrelation of extinction [corrected] and origination rates through time. Our results show that extinction rates are uncorrelated beyond the average duration of a stratigraphic interval. Thus, they lack the long-range correlations predicted by the self-organized criticality hypothesis. In contrast, origination rates show strong autocorrelations due to long-term trends. After detrending, origination rates generally show weak positive correlations at lags of 5-10 million years (Myr) and weak negative correlations at lags of 10-30 Myr, consistent with aperiodic oscillations around their long-term trends. We hypothesize that origination rates are more correlated than extinction rates because originations of new taxa create new ecological niches and new evolutionary pathways for reaching them, thus creating conditions that favour further diversification.


Assuntos
Evolução Biológica , Fósseis , Animais , Ecossistema , Análise de Fourier , Geologia/estatística & dados numéricos , Fatores de Tempo
14.
Biochem Pharmacol ; 46(3): 357-64, 1993 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-8347161

RESUMO

Clofibryl and fenofibryl acyl (ester) glucuronides (CAG and FAG) are major metabolites in humans of the hypolipidaemic drugs clofibrate and fenofibrate, respectively. We have investigated three inter-related aspects of the reactivity of CAG and FAG in human serum albumin (HSA) solution, human plasma and in buffer at pH 7.0: namely (a) rearrangement via acyl migration to glucuronic acid esters of clofibric acid (CA) and fenofibric acid (FA), (b) hydrolysis of the parent glucuronide and rearrangement products to yield CA and FA and (c) the formation of covalent adducts with albumin and plasma protein. CAG was more reactive than FAG in all media, especially the protein solutions. The reactivity of both glucuronides was accelerated in protein solution compared with buffer and this was more marked in plasma than in HSA solution. The predominant reaction during the initial stages of the incubation was formation of isomeric rearrangement products. In the protein solutions, CA and FA were the major reaction products after 24 hr, compared to the rearranged isomers in buffer. Protein binding of 14C to HSA was markedly higher after incubation of CAG and FAG labelled on the glucuronyl moiety compared with the label on the aglycone. This is consistent with the covalent binding of CAG and FAG to protein proceeding via the formation of a Schiff's base rather than by transacylation.


Assuntos
Ácido Clofíbrico/química , Fenofibrato/análogos & derivados , Glucuronatos/química , Soluções Tampão , Ácido Clofíbrico/sangue , Fenofibrato/sangue , Fenofibrato/química , Glucuronatos/sangue , Humanos , Técnicas In Vitro , Ligação Proteica , Albumina Sérica/química , Soluções
15.
Obstet Gynecol ; 52(1): 79-82, 1978 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-150558

RESUMO

Records of 606 therapeutic abortions performed by suction curettage, 693 interval laparoscopic sterilizations, and 442 combined procedures were analyzed and compared. The following conclusions were obtained: 1) Abortion alone and abortion with laparoscopic sterilization are similar in rates of postoperative morbidity (4.3 and 7%, respectively) and early complications (3.3 and 2.9%, respectively). 2) The risks in laparoscopic sterilization alone are significantly lower for postoperative morbidity (2.2%) and early complications (0.9%) than for abortion alone or for the combined procedure.


Assuntos
Aborto Terapêutico , Laparoscopia , Esterilização Tubária/métodos , Adulto , Feminino , Humanos , Complicações Pós-Operatórias/epidemiologia , Gravidez , Risco , Curetagem a Vácuo
16.
Obstet Gynecol ; 68(1): 106-10, 1986 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3725240

RESUMO

Variations of urethral pressure were registered with microtransducers in 427 gynecologic patients with lower urinary tract symptoms during urethrocystometry. Urethral instability (variation of urethral pressure greater than 15 cm of water) was found in 16.4% of patients. The comparison of the urinary symptoms and the urodynamic data between patients with urethral instability (without previous surgery for incontinence, N = 57), and patients with stable urethra (variation of urethral pressure less than 5 cm of water, N = 269) showed that urethral instability was related to frequency, nycturia, urgency, and a history of urethral syndrome. In 27% of patients, the urethral instability was associated with a bladder instability. The comparison between patients with urethral instability and stable bladder (N = 51) and patients with bladder instability and stable urethra (N = 41) revealed that bladder instability seems to be more important than urethral instability as a factor associated with nycturia, urgency, and urge incontinence.


Assuntos
Uretra/fisiopatologia , Doenças Uretrais/fisiopatologia , Incontinência Urinária/fisiopatologia , Urodinâmica , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Pressão , Síndrome , Transdutores de Pressão , Doenças Uretrais/diagnóstico , Incontinência Urinária/diagnóstico , Transtornos Urinários/diagnóstico , Transtornos Urinários/fisiopatologia
17.
Obstet Gynecol ; 95(5): 643-7, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10775721

RESUMO

OBJECTIVE: To determine whether anal endosonography immediately after vaginal delivery can predict subsequent fecal incontinence. METHODS: We studied nulliparas who delivered vaginally and had no anal sphincter tears (third- or fourth-degree perineal tears) diagnosed clinically by endosonography before any suture of the perineum. The sonographer was unaware of delivery details and the obstetrician and the women were not informed of endosonography results. Therefore, the suture of the perineum and the outcomes were not influenced by sonographer's diagnoses. Three months after delivery, we assessed fecal incontinence by self-administered questionnaires. RESULTS: Clinically undetected tears of the anal sphincter were diagnosed by anal endosonography in 42 of 150 women (28%). The external anal sphincter alone was involved in 30 women (20%), the internal anal sphincter alone in two (1.3%), and both in ten (7%). The postal questionnaire was returned by 144 women. Incontinence was reported by 22 (15%, 95% confidence interval [CI] 10%, 22%), consisting mainly of incontinence to flatus only (16 of 22, 73%, 95% CI 50%, 89%). Clinically undetected anal sphincter tears diagnosed by endosonography were associated with incontinence 3 months after delivery (odds ratio [OR] 8.8; 95% CI 2.9, 26.5). The sensitivity of anal endosonography was 68% (95% CI 49%, 88%) and the positive predictive value 37% (95% CI 22%, 51%). CONCLUSION: Anal endosonography immediately after vaginal delivery allows diagnosis of clinically undetected anal sphincter tears that might be associated with subsequent fecal incontinence.


Assuntos
Canal Anal/diagnóstico por imagem , Canal Anal/lesões , Incontinência Fecal/diagnóstico , Complicações do Trabalho de Parto/diagnóstico por imagem , Transtornos Puerperais/diagnóstico , Adulto , Incontinência Fecal/etiologia , Feminino , Humanos , Período Pós-Parto , Valor Preditivo dos Testes , Gravidez , Transtornos Puerperais/etiologia , Sensibilidade e Especificidade , Inquéritos e Questionários , Ultrassonografia
18.
Science ; 210(4468): 378, 1980 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-17837402
19.
Science ; 163(3872): 1145, 1969 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-5765324
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