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1.
Surg Neurol Int ; 15: 174, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38840619

RESUMO

Background: Oculomotor nerve palsy is often associated with diabetes mellitus or caused by compression by a cerebral aneurysm. Here, we report a rare case of oculomotor nerve palsy caused by compression by the posterior cerebral artery (PCA). Case Description: A 66-year-old woman suddenly developed diplopia and right blepharoptosis. Her symptoms suggested incomplete right oculomotor nerve palsy. Magnetic resonance imaging showed that a sharp curve in the right PCA had compressed the right oculomotor nerve. Microvascular decompression surgery was performed. Intraoperative findings showed that the P2 portion of the PCA had caused an indentation in the oculomotor nerve in the prepontine cistern. The transposition of the PCA with a prosthesis released the pressure. After the operation, her right blepharoptosis gradually improved. She had fully recovered by 48 days after the operation. Conclusion: Neurovascular compression (NVC) is recognized as the cause of hemifacial spasms, trigeminal neuralgia, and glossopharyngeal neuralgia. This case report demonstrated that NVC can also cause oculomotor nerve palsy. A high index of clinical suspicion can detect vascular compression of the oculomotor nerve. Prompt diagnosis and appropriate surgical management can achieve clinical improvement.

2.
Kyobu Geka ; 76(4): 279-283, 2023 Apr.
Artigo em Japonês | MEDLINE | ID: mdl-36997175

RESUMO

Prosthetic valve endocarditis is a fatal complication after valve replacement surgery. Early surgical intervention is recommended for patients who suffer from complications such as heart failure, valve dysfunction, and abscesses. In the present study, we evaluated the clinical characteristics of 18 patients who underwent surgery for prosthetic valve endocarditis at our institution between December 1990 and August 2022, and examined the appropriateness of the timing and method of surgery, and whether there was improvement in cardiac function. Guidelines-based surgical intervention resulted in improved survival and improved cardiac function in the early and late postoperative period.


Assuntos
Endocardite Bacteriana , Endocardite , Próteses Valvulares Cardíacas , Infecções Relacionadas à Prótese , Humanos , Endocardite Bacteriana/cirurgia , Endocardite Bacteriana/etiologia , Próteses Valvulares Cardíacas/efeitos adversos , Infecções Relacionadas à Prótese/cirurgia , Endocardite/cirurgia , Reoperação , Resultado do Tratamento , Valva Aórtica/cirurgia
3.
BMC Neurol ; 21(1): 353, 2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34517828

RESUMO

BACKGROUND: The aim of this study was to investigate whether default mode network (DMN) connectivity and brain white matter integrity at baseline were associated with severe cognitive impairments at baseline and poor cognitive outcomes after shunt placement in patients with idiopathic normal pressure hydrocephalus (iNPH). METHODS: Twenty consecutive patients with iNPH whose symptoms were followed for 6 months after shunt placement and 10 healthy controls (HCs) were enrolled. DMN connectivity and brain white matter integrity at baseline in the patients with iNPH and HCs were detected by using resting-state functional magnetic resonance imaging (MRI) with independent component analysis and diffusion tensor imaging, respectively, and these MRI indexes were compared between the patients with iNPH and HCs. Performance on neuropsychological tests for memory and executive function and on the gait test was assessed in the patients with iNPH at baseline and 6 months after shunt placement. We divided the patients with iNPH into the relatively preserved and reduced DMN connectivity groups using the MRI indexes for DMN connectivity and brain white matter integrity, and the clinical measures were compared between the relatively preserved and reduced DMN connectivity groups. RESULTS: Mean DMN connectivity in the iNPH group was significantly lower than that in the HC group and was significantly positively correlated with Rey auditory verbal learning test (RAVLT) immediate recall scores and frontal assessment battery (FAB) scores. Mean fractional anisotropy of the whole-brain white matter skeleton in the iNPH group was significantly lower than that in the HC group. The reduced DMN connectivity group showed significantly worse performance on the RAVLT at baseline and significantly worse improvement in the RAVLT immediate recall and recognition scores and the FAB scores than the preserved DMN connectivity group. Moreover, the RAVLT recognition score highly discriminated patients with relatively preserved DMN connectivity from those with relatively reduced DMN connectivity. CONCLUSIONS: Our findings indicated that iNPH patients with reduced DMN connectivity relative to the severity of brain white matter disruption have severe memory deficits at baseline and poorer cognitive outcomes after shunt placement. However, further larger-scale studies are needed to confirm these findings.


Assuntos
Hidrocefalia de Pressão Normal , Substância Branca , Cognição , Rede de Modo Padrão , Imagem de Tensor de Difusão , Humanos , Hidrocefalia de Pressão Normal/diagnóstico por imagem , Imageamento por Ressonância Magnética , Testes Neuropsicológicos , Substância Branca/diagnóstico por imagem
4.
Brain Commun ; 3(1): fcaa223, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33501426

RESUMO

Non-convulsive status epilepticus describes the syndrome of unexplained impaired consciousness in critically ill patients. Non-convulsive status epilepticus is very likely to lead to delayed diagnosis and poor outcomes because of the absence of convulsive symptoms. EEG is essential for the diagnosis of non-convulsive status epilepticus to establish the association between periodic discharges and rhythmic delta activity in addition to ictal epileptiform discharges according to the Salzburg criteria. Arterial spin labelling, a type of perfusion MRI, has been applied for rapid and non-invasive evaluation of the ictal state. Ictal cerebral cortical hyperperfusion is the most common finding to demonstrate focal onset seizures. Hyperperfusion of the thalamus on single photon emission computed tomography was found in patients with impaired awareness seizures. We hypothesized that thalamocortical hyperperfusion on arterial spin labelling identifies non-convulsive status epilepticus and such thalamic hyperperfusion specifically associates with periodic/rhythmic discharges producing impaired consciousness without convulsion. We identified 27 patients (17 females; age, 39-91 years) who underwent both arterial spin labelling and EEG within 24 h of suspected non-convulsive status epilepticus. We analysed 28 episodes of suspected non-convulsive status epilepticus and compared hyperperfusion on arterial spin labelling with periodic/rhythmic discharges. We evaluated 21 episodes as a positive diagnosis of non-convulsive status epilepticus according to the Salzburg criteria. We identified periodic discharges in 15 (12 lateralized and 3 bilateral independent) episodes and rhythmic delta activity in 13 (10 lateralized, 1 bilateral independent and 2 generalized) episodes. Arterial spin labelling showed thalamic hyperperfusion in 16 (11 unilateral and 5 bilateral) episodes and cerebral cortical hyperperfusion in 24 (20 unilateral and 4 bilateral) episodes. Thalamic hyperperfusion was significantly associated with non-convulsive status epilepticus (P = 0.0007; sensitivity, 76.2%; specificity, 100%), periodic discharges (P < 0.0001; 93.3%; 84.6%), and rhythmic delta activity (P = 0.0006; 92.3%; 73.3%). Cerebral cortical hyperperfusion was significantly associated with non-convulsive status epilepticus (P = 0.0017; 100%; 57.1%) and periodic discharges (P = 0.0349; 100%; 30.8%), but not with rhythmic delta activity. Thalamocortical hyperperfusion could be a new biomarker of non-convulsive status epilepticus according to the Salzburg criteria in critically ill patients. Specific thalamic hyperexcitability might modulate the periodic discharges and rhythmic delta activity associated with non-convulsive status epilepticus. Impaired consciousness without convulsions could be caused by predominant thalamic hyperperfusion together with cortical hyperperfusion but without ictal epileptiform discharges.

5.
J Neuroendovasc Ther ; 14(1): 22-29, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-37502379

RESUMO

Objective: Hereditary hemorrhagic telangiectasia (HHT) may be associated with paradoxical cerebral embolism caused by pulmonary arteriovenous malformation (PAVM). We present a case of HHT diagnosed by progressive anemia during anticoagulant therapy following mechanical thrombectomy. Case Presentation: The patient was a 59-year-old woman who presented with acute stroke due to intracranial large vessel occlusion. Mechanical thrombectomy was successfully performed and the thrombus was retrieved. Postoperatively, anticoagulant therapy was started; however, she developed progressive anemia, which was associated with marked weakness, although no bleeding source was detected. Thorough postoperative imaging studies revealed PAVMs, which may be a source of cerebral embolism. It was noted that she frequently had episodes of epistaxis and a family history of PAVM. Embolization of PAVMs was performed to prevent the recurrence of embolic disorders. After this procedure, anticoagulant therapy was safely discontinued, which resulted in the improvement of anemia. Conclusion: Physicians need to consider the possibility of HHT associated with PAVM which can cause paradoxical cerebral embolism.

6.
Chem Pharm Bull (Tokyo) ; 67(10): 1144-1151, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31582634

RESUMO

Definitive screening design (DSD) is a new class of small three-level experimental design that is attracting much attention as a technical tool of a quality by design (QbD) approach. The purpose of this study is to examine the usefulness of DSD for QbD through a pharmaceutical study on the preparation of ethenzamide-containing orally disintegrating tablet. Model tablets were prepared by directly compressing the mixture of the active pharmaceutical ingredient (API) and excipients. The five evaluated factors assigned to DSD were: the contents of API (X1) and lubricant (X2), and the compression force (X3) of the tableting process, the mixing time (X4), and the filling ratio of powder in the V-type mixer (X5). After tablet preparation, hardness and disintegration time were measured. The same experiments were performed by using the conventional design of experiments [i.e., L8 and L16 orthogonal array designs and central composite design (CCD)]. Results showed that DSD successfully clarified how various factors contribute to tablet properties. Moreover, the analysis result from DSD agreed well with those from the L8 and L16 experiments. In additional experiments, response surfaces for tablet properties were created by DSD. Compared with the response surfaces created by CCD, DSD could produce reliable response surfaces for its smaller number of experiments. We conclude that DSD is a powerful tool for implementing pharmaceutical studies including the QbD approach.


Assuntos
Desenho de Fármacos , Preparações Farmacêuticas/química , Composição de Medicamentos , Avaliação Pré-Clínica de Medicamentos , Preparações Farmacêuticas/administração & dosagem , Propriedades de Superfície , Comprimidos/administração & dosagem , Comprimidos/química
7.
Neurol Genet ; 5(3): e328, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31086825

RESUMO

OBJECTIVE: To identify XK pathologic mutations in 6 patients with suspected McLeod syndrome (MLS) and a possible interaction between the chorea-acanthocytosis (ChAc)- and MLS-responsible proteins: chorein and XK protein. METHODS: Erythrocyte membrane proteins from patients with suspected MLS and patients with ChAc, ChAc mutant carriers, and normal controls were analyzed by XK and chorein immunoblotting. We performed mutation analysis and XK immunoblotting to molecularly diagnose the patients with suspected MLS. Lysates of cultured cells were co-immunoprecipitated with anti-XK and anti-chorein antibodies. RESULTS: All suspected MLS cases were molecularly diagnosed with MLS, and novel mutations were identified. The average onset age was 46.8 ± 8 years, which was older than that of the patients with ChAc. The immunoblot analysis revealed remarkably reduced chorein immunoreactivity in all patients with MLS. The immunoprecipitation analysis indicated a direct or indirect chorein-XK interaction. CONCLUSIONS: In this study, XK pathogenic mutations were identified in all 6 MLS cases, including novel mutations. Chorein immunoreactions were significantly reduced in MLS erythrocyte membranes. In addition, we demonstrated a possible interaction between the chorein and XK protein via molecular analysis. The reduction in chorein expression is similar to that between Kell antigens and XK protein, although the chorein-XK interaction is a possibly noncovalent binding unlike the covalent Kell-XK complex. Our results suggest that reduced chorein levels following lack of XK protein are possibly associated with molecular pathogenesis in MLS.

8.
BMC Neurol ; 17(1): 157, 2017 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-28793877

RESUMO

BACKGROUND: Cryptococcal meningoencephalitis (CM) causes cerebral infarction, typically, lacunar infarction in the basal ganglia. However, massive cerebral infarction leading to death is rare and its pathophysiology is unclear. We report a case of CM causing massive cerebellar infarction, which led to cerebral herniation and death. CASE PRESENTATION: A 56-year-old man who suffered from dizziness and gait disturbance for one month was admitted to our hospital and subsequently diagnosed with a cerebellar infarction. He had a past medical history of hepatitis type B virus infection and hepatic failure. Although the findings on magnetic resonance imaging (MRI) imitated an arterial infarction of the posterior inferior cerebellar artery, an accompanying irregular peripheral edema was observed. The ischemic lesion progressed, subsequently exerting a mass effect and leading to impaired consciousness. External and internal decompression surgeries were performed. Cryptococcus neoformans was confirmed in the surgical specimen, and the patient was diagnosed with CM. In addition, venule congestion in the parenchyma was observed with extensive fibrosis and compressed veins in the subarachnoid space. The patient died 26 days after admission. Autopsy revealed that pathological changes were localized in the cerebellum. CONCLUSION: C. neoformans can induce extensive fibrosis of the subarachnoid space, which may compress small veins mechanically inducing venule congestion and massive cerebral infarction. In such cases, the clinical course can be severe and even rapidly fatal. An atypical pattern of infarction on MRI should alert clinicians to the possibility of C. neoformans infection.


Assuntos
Doenças Cerebelares/etiologia , Infarto Cerebral/etiologia , Meningoencefalite/complicações , Autopsia , Gânglios da Base/patologia , Cerebelo/patologia , Evolução Fatal , Humanos , Infarto/etiologia , Imageamento por Ressonância Magnética , Masculino , Meningite Criptocócica/complicações , Pessoa de Meia-Idade
9.
Cerebrovasc Dis ; 44(3-4): 105-112, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28605739

RESUMO

BACKGROUND: The presence of high-density starry dots around the intracerebral hemorrhage (ICH), which we termed as a satellite sign, is occasionally observed in CT. The relationship between ICH with a satellite sign and its functional outcome has not been identified. This study aimed to determine whether the presence of a satellite sign could be an independent prognostic factor for patients with ICH. METHODS: Patients with acute spontaneous ICH were retrospectively identified and their initial CT scans were reviewed. A satellite sign was defined as scattered high-density lesions completely separate from the main hemorrhage in at least the single axial slice. Functional outcome was evaluated using the modified Rankin Scale (mRS) at discharge. Poor functional outcome was defined as mRS scores of 3-6. Univariate and multivariate logistic regression analyses were applied to assess the presence of a satellite sign and its association with poor functional outcome. RESULTS: A total of 241 patients with ICH were enrolled in the study. Of these, 98 (40.7%) had a satellite sign. Patients with a satellite sign had a significantly higher rate of poor functional outcome (95.9%) than those without a satellite sign (55.9%, p < 0.0001). Multivariate logistic regression analysis revealed that higher age (OR 1.06; 95% CI 1.03-1.10; p = 0.00016), large hemorrhage size (OR 1.06; 95% CI 1.03-1.11; p = 0.00015), and ICH with a satellite sign (OR 13.5; 95% CI 4.42-53.4; p < 0.0001) were significantly related to poor outcome. A satellite sign was significantly related with higher systolic blood pressure (p = 0.0014), higher diastolic blood pressure (p = 0.0117), shorter activated partial thromboplastin time (p = 0.0427), higher rate of intraventricular bleeding (p < 0.0001), and larger main hemorrhage (p < 0.0001). CONCLUSIONS: The presence of a satellite sign in the initial CT scan is associated with a significantly worse functional outcome in ICH patients.


Assuntos
Angiografia Cerebral/métodos , Hemorragia Cerebral/diagnóstico por imagem , Angiografia por Tomografia Computadorizada , Acidente Vascular Cerebral/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Hemorragia Cerebral/mortalidade , Hemorragia Cerebral/fisiopatologia , Avaliação da Deficiência , Feminino , Humanos , Estimativa de Kaplan-Meier , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Acidente Vascular Cerebral/mortalidade , Acidente Vascular Cerebral/fisiopatologia
10.
Appl Spectrosc ; 70(9): 1476-88, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27503327

RESUMO

While the sampling of pharmaceutical products typically follows well-defined protocols, the parameterization of spectroscopic methods and their associated sampling frequency is not standard. Whereas, for blending, the sampling frequency is limited by the nature of the process, in other processes, such as tablet film coating, practitioners must determine the best approach to collecting spectral data. The present article studied how sampling practices affected the interpretation of the results provided by a near-infrared spectroscopy method for the monitoring of tablet moisture and coating weight gain during a pan-coating experiment. Several coating runs were monitored with different sampling frequencies (with or without co-adds (also known as sub-samples)) and with spectral averaging corresponding to processing cycles (1 to 15 pan rotations). Beyond integrating the sensor into the equipment, the present work demonstrated that it is necessary to have a good sense of the underlying phenomena that have the potential to affect the quality of the signal. The effects of co-adds and averaging was significant with respect to the quality of the spectral data. However, the type of output obtained from a sampling method dictated the type of information that one can gain on the dynamics of a process. Thus, different sampling frequencies may be needed at different stages of process development.


Assuntos
Química Farmacêutica/métodos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Comprimidos/análise , Comprimidos/química , Reprodutibilidade dos Testes
11.
Artigo em Inglês | MEDLINE | ID: mdl-27338441

RESUMO

Certain attitudes toward suicide may be a risk factor for suicide among the bereaved. To explore this possibility, we examined the relationship between attitudes toward suicide and family history of suicide. We focused on two specific attitudes indicating resignation in a survey: #1 "When a person chooses to die by suicide, the suicide is inevitable" (i.e., inevitability belief); and #2 "A suicide cannot be stopped by any person, because suicide is unpreventable" (i.e., unpreventable belief). The data of 5117 fully completed questionnaires were analyzed. Logistic regression analysis revealed that the two attitudes of resignation were significantly associated with a family history of suicide. The adjusted odds ratio for #1 was 1.39 (95% CI, 1.07-1.79) for individuals having experienced suicide by a family member or relative, while that for #2 was 1.57 (95% CI, 1.27-1.95) for experiencing a suicide by a family member or relative and 1.25 (95% CI, 1.05-1.49) for experiencing a suicide by a friend, business associate, partner or other. These two attitudes of resignation toward suicide were significantly associated with a family history of suicide. These attitudes might increase suicide risk among the bereaved.


Assuntos
Atitude Frente a Morte , Família/psicologia , Suicídio/psicologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Inquéritos e Questionários , Adulto Jovem
12.
Environ Health Prev Med ; 21(3): 164-72, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26883050

RESUMO

OBJECTIVES: Feeling ashamed for seeking help when distressed is known to be a critical factor promoting suicidal behaviors. The objective of this study was to examine the relationship between suicidal ideation and psychosocial factors, including worries or anxieties, having a person to confide in, feeling ashamed for seeking help when distressed, and K6 score. METHODS: Fourteen out of 77 municipalities from Nagano Prefecture participated in this questionnaire survey. Participants of both sexes over 20 years of age were randomly selected according to age distribution in each municipality. Association between suicidal ideation and sociodemographic and psychosocial factors, including "feeling ashamed for seeking help", were determined by multiple logistic regression analysis. RESULTS: Among a total of 11,100 participants, 7394 (66.6%) returned the questionnaire. 2147 participants responded properly to essential study parameters and were submitted to the final analyses. The adjusted odds ratio of suicidal ideation was 2.09 (95% CI 1.49-2.94) among participants feeling ashamed for seeking help, compared to those not feeling ashamed. Although the rate of "no person to confide in" was 4.4%, participants who responded with "no person to confide in" had significantly increased odds ratio of suicidal ideation compared with those who responded with "having a person to confide in" (OR 1.97, 95% CI 1.12-3.47). CONCLUSIONS: Our findings suggest a need for tailored intervention targeting individuals at risk by gatekeepers to encourage individuals at risk to overcome feeling ashamed for seeking help and to cultivate an appropriate person to confide in.


Assuntos
Ideação Suicida , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Psicologia/estatística & dados numéricos , Fatores de Risco , Inquéritos e Questionários , Adulto Jovem
13.
J Pharm Sci ; 101(7): 2372-81, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22473528

RESUMO

The aim of this study was to create a tablet database for use in designing tablet formulations. We focused on the contribution of active pharmaceutical ingredients (APIs) to tablet properties such as hardness and disintegration time (DT). Before we investigated the effects of the APIs, we optimized the tablet base formulation (placebo tablet) according to an expanded simplex search. The optimal placebo tablet showed sufficient hardness and rapid disintegration. We then tested 14 kinds of compounds as the model APIs. The APIs were characterized in terms of their physicochemical properties using Kohonen's self-organizing maps. We also prepared model tablets by incorporating the APIs into the optimal placebo tablet, and then examined the tablet properties, including tensile strength and DT. On the basis of the experimental data, an ensemble artificial neural network incorporating general regression analysis was conducted. A reliable model of the correlation between the physicochemical properties of the APIs and the tablet properties was thus constructed. From the correlation model, we clarified the detailed contributions of each physicochemical property to the tablet attributes.


Assuntos
Preparações Farmacêuticas/química , Comprimidos/química , Dureza , Modelos Químicos , Redes Neurais de Computação , Análise de Regressão , Solubilidade
14.
Chem Pharm Bull (Tokyo) ; 59(5): 608-17, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21532199

RESUMO

The design space of the granulation process of mefenamic acid tablets, based on Box and Behnken design datasets, was described by a response surface method incorporating multivariate spline interpolation. The reliability of the optimal solutions and the acceptance ranges were evaluated by a bootstrap (BS) resampling technique. The distribution of the BS optimal solutions was almost symmetrical; however, several solutions, which were quite different from the original solution, were mixed. The reason for this problem was considered to be the mixing of the global and the local optima. Therefore, we applied self-organizing map (SOM) clustering for dividing data into several clusters and identified the cluster containing the global optima. The accuracy and reproducibility of the optimal solution in the cluster containing the optimal solution were quantitatively evaluated. In addition, the response surfaces modeled from all the BS datasets contained in the cluster were plotted into the same coordinates with the original response surface. The plots of BS optimal solutions were distributed around the original solution. Moreover, the average of all the BS response surfaces sufficiently corresponded with the original response surface. The conservative limits of the 95% confidence intervals of the acceptance ranges in three response variables could be calculated using the standard deviations of the BS response surfaces. Consequently, it was considered that a novel evaluation method based on BS resampling and SOM could be used for quantitatively evaluating the precision of the nonlinear response surface model.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Química Farmacêutica/métodos , Ácido Mefenâmico/farmacologia , Pós/química , Comprimidos/química , Anti-Inflamatórios não Esteroides/química , Desenho de Fármacos , Ácido Mefenâmico/química , Reprodutibilidade dos Testes , Resistência ao Cisalhamento
15.
J Pharm Sci ; 99(10): 4201-14, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20310024

RESUMO

A tablet database containing several active ingredients for a standard tablet formulation was created. Tablet tensile strength (TS) and disintegration time (DT) were measured before and after storage for 30 days at 40 degrees C and 75% relative humidity. An ensemble artificial neural network (EANN) was used to predict responses to differences in quantities of excipients and physical-chemical properties of active ingredients in tablets. Most classical neural networks involve a tedious trial and error approach, but EANNs automatically determine basal key parameters, which ensure that an optimal structure is rapidly obtained. We compared the predictive abilities of EANNs in which the following kinds of training algorithms were used: linear, radial basis function, general regression (GR), and multilayer perceptron. The GR EANN predicted pharmaceutical responses such as TS and DT most accurately, as evidenced by high correlation coefficients in a leave-some-out cross-validation procedure. When used in conjunction with a tablet database, the GR EANN is capable of identifying acceptable candidate tablet formulations.


Assuntos
Química Farmacêutica , Redes Neurais de Computação , Comprimidos , Bases de Dados Factuais , Excipientes
16.
Chem Pharm Bull (Tokyo) ; 57(6): 572-9, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19483336

RESUMO

The optimal solutions of theophylline tablet formulations based on datasets from 4 experimental designs (Box and Behnken design, central composite design, D-optimal design, and full factorial design) were calculated by the response surface method incorporating multivariate spline interpolation (RSM(S)). Reliability of these solutions was evaluated by a bootstrap (BS) resampling technique. The optimal solutions derived from the Box and Behnken design, D-optimal design, and full factorial design dataset were similar. The distributions of the BS optimal solutions calculated for these datasets were symmetrical. Thus, the accuracy and the reproducibility of the optimal solutions enabled quantitative evaluation based on the deviations of these distributions. However, the distribution of the BS optimal solutions calculated for the central composite design dataset were almost unsymmetrical, and the basic statistic of these distributions could not be conducted. The reason for this problem was considered to be the mixing of the global and local optima. Therefore, self-organizing map (SOM) clustering was applied to identify the global optimal solutions. The BS optimal solutions were divided into 4 clusters by SOM clustering, the accuracy and reproducibility of the optimal solutions in each cluster were quantitatively evaluated, and the cluster containing the global optima was identified. Therefore, SOM clustering was considered to reinforce the BS resampling method for the evaluation of the reliability of optimal solutions irrespective of the dataset style.


Assuntos
Broncodilatadores/administração & dosagem , Teofilina/administração & dosagem , Algoritmos , Broncodilatadores/química , Química Farmacêutica , Análise por Conglomerados , Desenho de Fármacos , Excipientes , Dureza , Modelos Estatísticos , Pós , Reprodutibilidade dos Testes , Teofilina/química
17.
J Pharm Sci ; 97(1): 331-9, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17722113

RESUMO

The response surface method incorporating multivariate spline interpolation (RSM-S) is a powerful technique for the formulation optimization of pharmaceuticals. However, no satisfactory method has been developed to evaluate the reliability of the optimal solution. We integrated bootstrap (BS) resampling and Kohonen's self-organizing maps (SOM) into RSM-S using the formulation optimization of theophylline tablets as the model experiment. The hardness and the 63.2% drug-release times of the tablets were measured as response variables. Based on the data set obtained, the simultaneous optimal solution was estimated using RSM-S. Leave-one-out cross-validation showed the optimal solution to be reliable. Concurrently, a large number of BS samples were generated from the original data set using BS resampling, and simultaneous optimal solutions for each BS sample (BS optimal solutions) were estimated. The distribution of the BS optimal solutions was far from a normal distribution, suggesting a mixture of global and local optimal solutions. SOM clustering was used to identify the set of global optimal solutions. SOM clustering divided the BS optimal solutions into several clusters, and the reliability of the optimal solution was evaluated from the cluster that included the optimal solution. This study offers a promising method for evaluating the reliability of nonlinear optimal solutions. .


Assuntos
Química Farmacêutica/estatística & dados numéricos , Comprimidos/química , Algoritmos , Análise por Conglomerados , Composição de Medicamentos , Modelos Estatísticos , Análise Multivariada , Dinâmica não Linear , Reprodutibilidade dos Testes , Software , Teofilina/administração & dosagem , Teofilina/química
18.
Chem Pharm Bull (Tokyo) ; 55(4): 586-93, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17409553

RESUMO

Optimal solutions of theophylline tablet formulations were derived from three types of experimental datasets, composed of different numbers of data-points using the response surface method incorporating multivariate spline interpolation (RSM(S)). The reliability of these optimal solutions was evaluated by a bootstrap re-sampling technique. Different levels of three causal factors were used as factors of response surface analysis: the lactose/cornstarch ratio (X(1)), the amount of carmellose calcium (X(2)), and the amount of hydroxypropylcellulose (X(3)). The target responses were the dissolution ratio of theophylline for the first 15 min (Y(1)) and the hardness (Y(2)) of each of the prepared tablets. Similar optimal solutions were estimated in three different sizes of datasets. A bootstrap re-sampling with replacements from the original dataset was applied, and optimal solutions for each bootstrap dataset were estimated. The frequency of the distribution of the optimal solution generated by the bootstrap re-sampling technique demonstrated almost normal distribution. The average and standard deviation of the optimal solution distribution were calculated as evaluation indices reflecting the accuracy and reproducibility of the optimal solution. It was confirmed that the accuracy was sufficiently high, irrespective of the dataset size; however, the reproducibility worsened with a decrease in the number of the experimental datasets. Consequently, it was considered that the novel evaluation method based on the bootstrap re-sampling technique was suitable for evaluating the reliability of the optimal solution.


Assuntos
Química Farmacêutica , Teofilina/química , Análise Multivariada , Soluções
19.
No Shinkei Geka ; 33(9): 925-9, 2005 Sep.
Artigo em Japonês | MEDLINE | ID: mdl-16164190

RESUMO

We reported an autopsy case of Down's syndrome with moyamoya syndrome. A 30-year-old male with Down's syndrome suffered from a cerebral infarction and died of brain herniation. Cerebral angiography showed vascular abnormalities that were the same as moyamoya disease. Pathological findings revealed multiple stenosis of main trunk of the cerebral arteries. Pathologically, the stenosed vessels showed eccentric intimal thickness with cholesterin deposit, unlike moyamoya disease. There are only two previous reports of autopsied cases of Down's syndrome with moyamoya syndrome. We postulate that a protein encoded on chromosome 21 may be related to the pathogenesis of Down's syndrome with moyamoya syndrome.


Assuntos
Síndrome de Down/complicações , Doença de Moyamoya/complicações , Adulto , Humanos , Masculino , Doença de Moyamoya/diagnóstico por imagem , Doença de Moyamoya/patologia , Radiografia
20.
Neuropathology ; 23(3): 195-8, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-14570286

RESUMO

Post-mortem examinations of the circle of Willis in two cases of subarachnoid hemorrhage disclosed a wide spectrum of vasculopathy ranging from a minimal tear between the intima and media, and between the media and adventitia, to complete transmural disruption leading to the formation of pseudoaneurysms. The presence of coexistence of the focal lesions with complete replacement of the entire arterial wall with thick fibrous connective tissues and the vasculopathy was suggestive of the spontaneous repair of recurrent non-traumatic dissection of intracranial arteries. The patients were 58-year-old and 43-year-old females. There was no history of injury to the head or neck in either case. They were hypertensive, but the degree of atherosclerotic changes in the circle of Willis was compatible with age. There was no histological evidence of vasculitis. The role of hypertension and medial mucoid degeneration in the genesis of non-traumatic dissection of intracranial arteries was discussed.


Assuntos
Dissecção Aórtica/patologia , Encéfalo/irrigação sanguínea , Encéfalo/patologia , Círculo Arterial do Cérebro/patologia , Adulto , Falso Aneurisma/etiologia , Falso Aneurisma/patologia , Feminino , Humanos , Hipertensão/complicações , Aneurisma Intracraniano/complicações , Aneurisma Intracraniano/patologia , Lúpus Eritematoso Sistêmico/complicações , Pessoa de Meia-Idade , Recidiva , Remissão Espontânea , Hemorragia Subaracnóidea/etiologia
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