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1.
Oncol Lett ; 27(5): 212, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38572063

RESUMO

Trefoil factor family member 2 (Tff2) is significantly involved in intestinal tumor growth in ApcMin/+ mice, which can be used as a human colon cancer model. TFF2, which encodes TFF2 (spasmolytic protein 1) is highly expressed in human cancer tissues, including the pancreas, colon and bile ducts, as well as in normal gastric and duodenum tissues. By contrast, TFF2 exhibits low expression levels in other normal tissues, including the small and large intestine. Furthermore, TFF2 expression has not been detected in DLD-1 cells, a cell line derived from human colon cancer. What induces TFF2 expression in normal and tumor cells is still unknown. Highly malignant tumor tissues are characterized by higher temperatures and lower pH (6.2-6.9) than in normal tissues, where normal pH ranges from 7.2 to 7.4. This microenvironment exacerbates malignancy by promoting the acquisition of cell death resistance, drug resistance and immune escape. Therefore, the present study examined how TFF2 expression is affected in cultured cells that imitate the tumor tissue microenvironment. The incubation temperature was increased from 37 to 40°C, but no expression of TFF2 was induced. Subsequently, a culture solution with an acidic pH was prepared to simulate the Warburg effect in tumors. TFF2 expression was increased by 42.8- and 5.8-fold in cells cultured in acidic medium at pH 6.5 and 6.8 compared with at pH 7.4, respectively, as determined using the relative quantification method following quantitative polymerase chain reaction. The present study also analyzed fluctuations in the expression levels of genes other than TFF2, under acidic conditions. Acidic conditions upregulated the expression of genes related to cell membranes and glycoproteins, based on the Database for Annotation, Visualization, and Integrated Discovery. In conclusion, TFF2 was highly expressed under acidic conditions, implying that it may have an important function in protecting the plasma membrane from acidic environments in both normal and cancer cells. These findings warrant further investigation of TFF2 as a target of cancer therapy and diagnosis.

2.
Elife ; 122023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-38096104

RESUMO

One limitation on the ability to monitor health in older adults using magnetic resonance (MR) imaging is the presence of implants, where the prevalence of implantable devices (orthopedic, cardiac, neuromodulation) increases in the population, as does the pervasiveness of conditions requiring MRI studies for diagnosis (musculoskeletal diseases, infections, or cancer). The present study describes a novel multiphysics implant modeling testbed using the following approaches with two examples: (1) an in silico human model based on the widely available Visible Human Project (VHP) cryo-section dataset; (2) a finite element method (FEM) modeling software workbench from Ansys (Electronics Desktop/Mechanical) to model MR radio frequency (RF) coils and the temperature rise modeling in heterogeneous media. The in silico VHP-Female model (250 parts with an additional 40 components specifically characterizing embedded implants and resultant surrounding tissues) corresponds to a 60-year-old female with a body mass index of 36. The testbed includes the FEM-compatible in silico human model, an implant embedding procedure, a generic parameterizable MRI RF birdcage two-port coil model, a workflow for computing heat sources on the implant surface and in adjacent tissues, and a thermal FEM solver directly linked to the MR coil simulator to determine implant heating based on an MR imaging study protocol. The primary target is MR labeling of large orthopedic implants. The testbed has very recently been approved by the US Food and Drug Administration (FDA) as a medical device development tool for 1.5 T orthopedic implant examinations.


Assuntos
Temperatura Alta , Próteses e Implantes , Feminino , Humanos , Idoso , Pessoa de Meia-Idade , Simulação por Computador , Temperatura , Imageamento por Ressonância Magnética/métodos
3.
bioRxiv ; 2023 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-37649909

RESUMO

One limitation on the ability to monitor health in older adults using Magnetic Resonance (MR) imaging is the presence of implants, where the prevalence of implantable devices (orthopedic, cardiac, neuromodulation) increases in the population, as does the pervasiveness of conditions requiring MRI studies for diagnosis (musculoskeletal diseases, infections, or cancer). The present study describes a novel multiphysics implant modeling testbed using the following approaches with two examples: - an in-silico human model based on the widely available Visible Human Project (VHP) cryo-section dataset; - a finite element method (FEM) modeling software workbench from Ansys (Electronics Desktop/Mechanical) to model MR radio frequency (RF) coils and the temperature rise modeling in heterogeneous media. The in-silico VHP Female model (250 parts with an additional 40 components specifically characterizing embedded implants and resultant surrounding tissues) corresponds to a 60-year-old female with a body mass index (BMI) of 36. The testbed includes the FEM-compatible in-silico human model, an implant embedding procedure, a generic parameterizable MRI RF birdcage two-port coil model, a workflow for computing heat sources on the implant surface and in adjacent tissues, and a thermal FEM solver directly linked to the MR coil simulator to determine implant heating based on an MR imaging study protocol. The primary target is MR labeling of large orthopaedic implants. The testbed has very recently been approved by the US Food and Drug Administration (FDA) as a medical device development tool (MDDT) for 1.5 T orthopaedic implant examinations.

4.
PLoS One ; 16(12): e0260922, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34890429

RESUMO

Quantitative modeling of specific absorption rate and temperature rise within the human body during 1.5 T and 3 T MRI scans is of clinical significance to ensure patient safety. This work presents justification, via validation and comparison, of the potential use of the Visible Human Project (VHP) derived Computer Aided Design (CAD) female full body computational human model for non-clinical assessment of female patients of age 50-65 years with a BMI of 30-36 during 1.5 T and 3 T based MRI procedures. The initial segmentation validation and four different application examples have been identified and used to compare to numerical simulation results obtained using VHP Female computational human model under the same or similar conditions. The first application example provides a simulation-to-simulation validation while the latter three application examples compare with measured experimental data. Given the same or similar coil settings, the computational human model generates meaningful results for SAR, B1 field, and temperature rise when used in conjunction with the 1.5 T birdcage MRI coils or at higher frequencies corresponding to 3 T MRI. Notably, the deviation in temperature rise from experiment did not exceed 2.75° C for three different heating scenarios considered in the study with relative deviations of 10%, 25%, and 20%. This study provides a reasonably systematic validation and comparison of the VHP-Female CAD v.3.0-5.0 surface-based computational human model starting with the segmentation validation and following four different application examples.


Assuntos
Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Projetos Ser Humano Visível , Idoso , Feminino , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Imagens de Fantasmas , Ondas de Rádio
6.
Front Physiol ; 9: 1439, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30459628

RESUMO

Purpose: The purpose of this study was to investigate the need for high-resolution detailed anatomical modeling to correctly estimate radio-frequency (RF) safety during magnetic resonance imaging (MRI). RF-induced heating near metallic implanted devices depends on the electric field tangential to the device (Etan ). Etan and specific absorption rate (SAR) were analyzed in blood vessels of an anatomical model to understand if a standard gel phantom accurately represents the potential heating in tissues due to passive vascular implants such as stents. Methods: A numerical model of an RF birdcage body coil and an anatomically realistic virtual patient with a native spatial resolution of 1 mm3 were used to simulate the in vivo electric field at 64 MHz (1.5 T MRI system). Maximum values of SAR inside the blood vessels were calculated and compared with peaks in a numerical model of the ASTM gel phantom to see if the results from the simplified and homogeneous gel phantom were comparable to the results from the anatomical model. Etan values were also calculated in selected stent trajectories inside blood vessels and compared with the ASTM result. Results: Peak SAR values in blood vessels were up to ten times higher than those found in the ASTM standard gel phantom. Peaks were found in clinically significant anatomical locations, where stents are implanted as per intended use. Furthermore, Etan results showed that volume-averaged SAR values might not be sufficient to assess RF safety. Conclusion: Computational modeling with a high-resolution anatomical model indicated higher values of the incident electric field compared to the standard testing approach. Further investigation will help develop a robust safety testing method which reflects clinically realistic conditions.

7.
Intern Med ; 57(7): 1039-1043, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29269659

RESUMO

We describe a case of a woman who presented with a persistent cough, general fatigue, and a fever. Interstitial lung disease was rapidly progressive and resistant to high-dose steroid therapy. She tested positive for the presence of anti-melanoma differentiation-associated gene 5 (MDA-5) antibody, although she had no skin manifestations of dermatomyositis. She was eventually diagnosed with unclassifiable idiopathic interstitial pneumonia and was successfully treated with intensive immunosuppressive therapy including intravenous cyclophosphamide. To our knowledge, this is the first report of anti-MDA-5 antibody in a patient with idiopathic interstitial pneumonia.


Assuntos
Anticorpos/genética , Ciclofosfamida/uso terapêutico , Pneumonias Intersticiais Idiopáticas/tratamento farmacológico , Fibrose Pulmonar Idiopática/tratamento farmacológico , Imunossupressores/uso terapêutico , Melanoma/genética , Melanoma/imunologia , Feminino , Humanos , Pneumonias Intersticiais Idiopáticas/complicações , Pneumonias Intersticiais Idiopáticas/diagnóstico por imagem , Fibrose Pulmonar Idiopática/diagnóstico por imagem , Pessoa de Meia-Idade , Resultado do Tratamento
8.
J Clin Biochem Nutr ; 60(3): 199-207, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28584401

RESUMO

It is important to establish effective methods for preventing colorectal cancer because the number of colorectal cancer deaths is increasing. Erythromycin one of the macrolide antibiotics, has been shown to exert pleiotropic effects, such as anti-inflammatory and anti-oxidative effects, on mammalian cells. In the present study, we aimed to evaluate the preventive effects of erythromycin on intestinal carcinogenesis. We first confirmed that erythromycin suppresses the transcriptional activity of nuclear factor-κB and activator protein-1 and the expression of its downstream targets, interleukin-6 and cyclooxygenase-2 in human colon cancer cells. Next, we fed 5-week-old male Apc mutant Min mice with diets containing 500 ppm erythromycin for 15 weeks. Erythromycin treatment significantly reduced the number of proximal intestinal polyps to 70.9% of the untreated control value. Moreover, erythromycin reduced the levels of interleukin-6 and cyclooxygenase-2 mRNA expression in intestinal polyps. Although the levels of hepatic NADPH oxidase mRNA were decreased, erythromycin treatment did not affect the levels of oxidative stress markers, reactive carbonyl species, in the liver of Min mice. Our results suggest that erythromycin suppresses intestinal polyp development in Min mice, in part by attenuating local inflammation, and indicate that erythromycin is useful as a chemopreventive agent.

9.
Int J Mol Sci ; 18(4)2017 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-28406434

RESUMO

Establishing effective methods for preventing colorectal cancer by so-called "functional foods" is important because the global burden of colorectal cancer is increasing. Enterococcus faecalis strain EC-12 (EC-12), which belongs to the family of lactic acid bacteria, has been shown to exert pleiotropic effects, such as anti-allergy and anti-infectious effects, on mammalian cells. In the present study, we aimed to evaluate the preventive effects of heat-killed EC-12 on intestinal carcinogenesis. We fed 5-week-old male and female Apc mutant Min mice diets containing 50 or 100 ppm heat-killed EC-12 for 8 weeks. In the 50 ppm treated group, there was 4.3% decrease in the number of polyps in males vs. 30.9% in females, and significant reduction was only achieved in the proximal small intestine of female mice. A similar reduction was observed in the 100 ppm treated group. Moreover, heat-killed EC-12 tended to reduce the levels of c-Myc and cyclin D1 mRNA expression in intestinal polyps. Next, we confirmed that heat-killed EC-12 suppressed the transcriptional activity of the T-cell factor/lymphoid enhancer factor, a transcriptional factor involved in cyclin D1 mRNA expression in intestinal polyps. Our results suggest that heat-killed EC-12 very weakly suppresses intestinal polyp development in Min mice, in part by attenuating ß-catenin signaling, and this implies that heat-killed EC-12 could be used as a "functional food".


Assuntos
Neoplasias Colorretais/prevenção & controle , Enterococcus faecalis/fisiologia , Animais , Carcinogênese , Linhagem Celular Tumoral , Quimioprevenção , Ciclina D1/genética , Ciclina D1/metabolismo , DNA Bacteriano/genética , DNA Bacteriano/metabolismo , Dieta , Enterococcus faecalis/genética , Face/microbiologia , Feminino , Alimento Funcional/microbiologia , Células HCT116 , Temperatura Alta , Humanos , Pólipos Intestinais/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , RNA Mensageiro , Transdução de Sinais , Fatores de Transcrição TCF/genética , Fatores de Transcrição TCF/metabolismo , Ativação Transcricional , beta Catenina/metabolismo
10.
Oncotarget ; 7(8): 8640-52, 2016 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-26840084

RESUMO

This study aimed to identify gastric mucosal protectants that suppress intestinal tumorigenesis in a mouse model. We chose six gastric mucosal protectants (ecabet sodium hydrate, irsogladine maleate, rebamipide, sofalcone, teprenone and troxipide) and examined their effects on the activity of oxidative stress-related transcriptional factors, including AP-1, NF-jB, NRF2, p53 and STAT3, in Caco-2 cells using a luciferase reporter gene assay. Among the six protectants, irsogladine maleate clearly inhibited NF-jB and AP-1 transcriptional activity. Furthermore, the chemopreventive property of irsogladine maleate was examined in a Min mouse model of familial adenomatous polyposis. Treatment with irsogladine maleate at doses of 5 and 50 ppm significantly reduced the number of intestinal polyps to 69% and 66% of the untreated control value, respectively. In these polyps, mRNA levels of the downstream targets of NF-jB, such as IL-1ß and IL-6, were decreased by irsogladine maleate treatment. Moreover, the levels of oxidative stress-related markers, reactive carbonyl species, in the livers of Min mice were clearly decreased following the administration of irsogladine maleate. This study demonstrated that irsogladine maleate suppresses intestinal polyp formation in Min mice partly through the NF-jB signaling pathway, thus reducing oxidative stress.


Assuntos
Antiulcerosos/farmacologia , Mucosa Gástrica/efeitos dos fármacos , Genes APC/fisiologia , Pólipos Intestinais/prevenção & controle , Mutação/genética , Triazinas/farmacologia , Animais , Apoptose/efeitos dos fármacos , Western Blotting , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Modelos Animais de Doenças , Mucosa Gástrica/metabolismo , Mucosa Gástrica/patologia , Humanos , Técnicas Imunoenzimáticas , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Interleucina-6/genética , Interleucina-6/metabolismo , Pólipos Intestinais/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/efeitos dos fármacos
11.
J Clin Biochem Nutr ; 57(1): 39-43, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26236099

RESUMO

Limonoids in citrus fruits are known to possess multiple biological functions, such as anti-proliferative functions in human cancer cell lines. Therefore, we aimed to investigate the suppressive effect of limonin on intestinal polyp development in Apc-mutant Min mice. Five-week-old female Min mice were fed a basal diet or a diet containing 250 or 500 ppm limonin for 8 weeks. The total number of polyps in mice treated with 500 ppm limonin decreased to 74% of the untreated control value. Neoplastic cell proliferation in the polyp parts was assessed by counting PCNA positive cells, and a tendency of reduction was obtained by limonin treatment. Moreover, expression levels of c-Myc and MCP-1 mRNA in the polyp part were reduced by administration of limonin. We finally confirmed the effects of limonin on ß-catenin signaling, and found limonin significantly inhibited T-cell factor/lymphocyte enhancer factor-dependent transcriptional activity in a dose-dependent manner in the Caco-2 human colon cancer cell line. Our results suggest that limonin might be a candidate chemopreventive agent against intestinal carcinogenesis.

12.
Cancer Sci ; 106(11): 1499-505, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26310859

RESUMO

Obesity is a risk factor for colorectal cancer. The accumulation of abdominal fat tissue causes abundant reactive oxygen species production through the activation of NADPH oxidase due to excessive insulin stimulation. The enzyme NADPH oxidase catalyzes the production of reactive oxygen species and evokes the initiation and progression of tumorigenesis. Apocynin is an NADPH oxidase inhibitor that blocks the formation of the NADPH oxidase complex (active form). In this study, we investigated the effects of apocynin on the development of azoxymethane-induced colonic aberrant crypt foci in obese KK-A(y) mice and on the development of intestinal polyps in Apc mutant Min mice. Six-week-old KK-A(y) mice were injected with azoxymethane (200 µg/mouse once per week for 3 weeks) and given 250 mg/L apocynin or 500 mg/L apocynin in their drinking water for 7 weeks. Six-week-old Min mice were also treated with 500 mg/L apocynin for 6 weeks. Treatment with apocynin reduced the number of colorectal aberrant crypt foci in KK-A(y) mice by 21% and the number of intestinal polyps in Min mice by 40% compared with untreated mice. Both groups of mice tended to show improved oxidation of serum low-density lipoprotein and 8-oxo-2'-deoxyguanosine adducts in their adipose tissues. In addition, the inducible nitric oxide synthase mRNA levels in polyp tissues decreased. Moreover, apocynin was shown to suppress nuclear factor-κB transcriptional activity in vitro. These results suggest that apocynin and other NADPH oxidase inhibitors may be effective colorectal cancer chemopreventive agents.


Assuntos
Acetofenonas/farmacologia , Antineoplásicos/farmacologia , Carcinogênese/efeitos dos fármacos , Neoplasias Colorretais/patologia , NADPH Oxidases/antagonistas & inibidores , Animais , Linhagem Celular Tumoral , Cromatografia Líquida , Modelos Animais de Doenças , Inibidores Enzimáticos/farmacologia , Feminino , Humanos , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Mutantes , Obesidade , Reação em Cadeia da Polimerase em Tempo Real , Espectrometria de Massas em Tandem
13.
Biochem Biophys Res Commun ; 463(4): 859-63, 2015 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-26056002

RESUMO

It is assumed that tumor size may be associated with malignant tumor conversion. However, the molecules responsible for determination of tumor size are not well understood. We counted the number of intestinal tumors in 8, 12 and 30-week-old Apc(Min/+) mice and measured tumor sizes, respectively. Genes involved in determining tumor size were examined using microarray analysis. Cultured cells were then, transfected with a mammalian expression vector containing a candidate gene to examine the functional role of the gene. The effect of forced expression of candidate gene on cell growth was evaluated by measuring the doubling time of the cultured cells and the growth of grafted cells in nude mice. Unexpectedly, microarray analysis identified trefoil factor family 2 (Tff2) rather than growth related genes and/or oncogenes as a most variable gene. Overexpressing Tff2 in cultured cells reduced doubling time in vitro and rapidly increased xenograft tumor size in vivo. We found Tff2 as a novel important factor that to be able to enlarge an intestinal tumor size.


Assuntos
Genes APC , Neoplasias Intestinais/patologia , Mucinas/fisiologia , Proteínas Musculares/fisiologia , Peptídeos/fisiologia , Animais , Sequência de Bases , Linhagem Celular Tumoral , Proliferação de Células , Primers do DNA , Xenoenxertos , Humanos , Camundongos , Camundongos Nus , Mucinas/genética , Proteínas Musculares/genética , Peptídeos/genética , Reação em Cadeia da Polimerase em Tempo Real , Fator Trefoil-2
14.
J Clin Biochem Nutr ; 56(1): 43-8, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25678750

RESUMO

Peyer's patches are nodules that play a central role in intestinal immunity. Few studies demonstrate the relationship between the number of Peyer's patches and intestinal polyps. Here we identify a statistically significant inverse correlation between the quantity of Peyer's patches and of the development of intestinal polyps in Apc (Min/+) mice, which are a useful model to clarify the role of Peyer's patches in intestinal tumorigenesis. Using this model, we increased the number of Peyer's patches using 0.1% and 1% corn husk arabinoxylan through feed. Intestinal polyp formation significantly decreased, concomitant with an increase in Peyer's patches development (n = 12/group). In Aly (-/-) Apc (Min/+) mice (negative control; no Peyer's patches) there was no change in the amount of intestinal polyps (n = 10/group). Immune reaction following corn husk arabinoxylan treatment was measured by cytokine array. Increasing the number of Peyer's patches decreased interleukin-17 production, which showed a dose dependent correlation with transcription factor/lymphoid enhancer-binding factor. This study identified a relationship between levels of Peyer's patches and intestinal polyp formation, partly explained by the involvement of interleukin-17 production and ß-catenin signaling in Apc (Min/+) mice.

15.
Eur J Cancer Prev ; 22(1): 8-10, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22504657

RESUMO

P-glycoprotein (P-gp; encoded by the Mdr1a gene) is known to be associated with colon tumorigenesis through transcriptional activation and/or epigenetic modification. We investigated whether inhibition of P-gp function might decrease intestinal tumorigenesis. We used verapamil as an inhibitor of P-gp function in Apc(Min/+) mice, which lack a functional Apc gene product. We determined the number of intestinal polyps and 1-year survival rates after the ingestion of 10, 25, and 50 mg/kg/day verapamil contained in dry pellets. The number of polyps in Mdr1a(+/+)Apc(Min/+) mice fed with pellets containing verapamil was significantly lower than that in mice fed with verapamil-free pellets. The 1-year survival rate of verapamil-fed mice was also improved in a dose-dependent manner. These results were similar to data from P-gp knockout mice. These results indicated that it might be possible to use verapamil to inhibit polyp development during the early stage of colon carcinogenesis. Thus, we propose a novel chemopreventive agent for colorectal cancer that acts by inhibiting P-gp function.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Genes APC , Pólipos Intestinais/genética , Pólipos Intestinais/prevenção & controle , Verapamil/administração & dosagem , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/fisiologia , Polipose Adenomatosa do Colo/genética , Polipose Adenomatosa do Colo/metabolismo , Polipose Adenomatosa do Colo/prevenção & controle , Animais , Modelos Animais de Doenças , Genes APC/fisiologia , Pólipos Intestinais/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
16.
PLoS One ; 7(9): e41187, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22984396

RESUMO

Intracranial electrocortical recording and stimulation can provide unique knowledge about functional brain anatomy in patients undergoing brain surgery. This approach is commonly used in the treatment of medically refractory epilepsy. However, it can be very difficult to integrate the results of cortical recordings with other brain mapping modalities, particularly functional magnetic resonance imaging (fMRI). The ability to integrate imaging and electrophysiological information with simultaneous subdural electrocortical recording/stimulation and fMRI could offer significant insight for cognitive and systems neuroscience as well as for clinical neurology, particularly for patients with epilepsy or functional disorders. However, standard subdural electrodes cause significant artifact in MRI images, and concerns about risks such as cortical heating have generally precluded obtaining MRI in patients with implanted electrodes. We propose an electrode set based on polymer thick film organic substrate (PTFOS), an organic absorbable, flexible and stretchable electrode grid for intracranial use. These new types of MRI transparent intracranial electrodes are based on nano-particle ink technology that builds on our earlier development of an EEG/fMRI electrode set for scalp recording. The development of MRI-compatible recording/stimulation electrodes with a very thin profile could allow functional mapping at the individual subject level of the underlying feedback and feed forward networks. The thin flexible substrate would allow the electrodes to optimally contact the convoluted brain surface. Performance properties of the PTFOS were assessed by MRI measurements, finite difference time domain (FDTD) simulations, micro-volt recording, and injecting currents using standard electrocortical stimulation in phantoms. In contrast to the large artifacts exhibited with standard electrode sets, the PTFOS exhibited no artifact due to the reduced amount of metal and conductivity of the electrode/trace ink and had similar electrical properties to a standard subdural electrode set. The enhanced image quality could enable routine MRI exams of patients with intracranial electrode implantation and could also lead to chronic implantation solutions.


Assuntos
Implantes Absorvíveis , Eletrodos Implantados , Imageamento por Ressonância Magnética/métodos , Compostos Orgânicos/química , Polímeros/química , Encéfalo/fisiopatologia , Simulação por Computador , Espectroscopia Dielétrica , Humanos , Reprodutibilidade dos Testes , Fatores de Tempo
17.
Med Mycol ; 46(4): 367-70, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18415845

RESUMO

A 52-year-old man without underlying diseases visited a local hospital with symptoms of memory deficit and mild headache. Radiological examination of the brain with computed tomography (CT) revealed hydrocephalus. Etiology was not revealed by cerebrospinal fluid (CSF) analysis and a ventricular-atrial (V-A) shunt was installed. The patient had congestion and dacryorrhea of the right eye and uveitis was diagnosed three months after placement of the V-A shunt. The serum cryptococcal antigen (CrAg) tested positive at a titration of 64 times. Additionally, samples of the right eye anterior chamber aqueous humor (ACAH), cerebrospinal fluid (CSF) and prostate fluid were positive for Cryptococcus antigen at a titration of 128 times. In addition, Cryptococcus neoformans var. grubii was isolated from the peripheral blood, CSF and ACAH, resulting in a diagnosis of disseminated cryptococcosis. Fluconazole (FLCZ) at 800 mg/day was administered for the first two days, followed by a 400 mg/day maintenance dose. After six months of treatment, his visual power recovered. This is a rare case of disseminated cryptococcosis involving uveitis, which was successfully treated by FLCZ. Disseminated cryptococcosis should be considered in cases with mild symptoms and V-A shunt installation for hydrocephalus.


Assuntos
Criptococose/diagnóstico , Endoftalmite/diagnóstico , Meningite Criptocócica/diagnóstico , Antifúngicos/uso terapêutico , Derivações do Líquido Cefalorraquidiano , Criptococose/complicações , Criptococose/tratamento farmacológico , Endoftalmite/complicações , Endoftalmite/tratamento farmacológico , Fluconazol/uso terapêutico , Soronegatividade para HIV , Humanos , Hidrocefalia/complicações , Masculino , Meningite Criptocócica/complicações , Meningite Criptocócica/tratamento farmacológico , Pessoa de Meia-Idade , Transtornos da Visão/etiologia , Transtornos da Visão/microbiologia
18.
Liver Int ; 23(5): 323-8, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14708892

RESUMO

BACKGROUND/AIMS: The antigen-driven clonal proliferation of B cells within target tissue has been reported in some autoimmune diseases. The purpose of this study was to examine the clonal characteristics of B cells in the liver portal area of primary biliary cirrhosis (PBC). METHODS: The liver portal area was microdissected from liver biopsy sections from two PBC patients. Genomic DNA was extracted and rearranged immunoglobulin heavy chain variable region (VH) genes were amplified and sequence analyzed. RESULTS: Sixteen VH sequences from portal area 1A of patient 1 had three different rearrangements. Nineteen VH sequences from portal area 1B of this patient had three different rearrangements. In three sequences from the portal area 1B, a stepwise accumulation of somatic mutations was observed. Between the sequences from the two portal areas, no common VH sequence was observed. In patient 2, 15 VH sequences from portal area 2A had three different rearrangements. Fourteen VH sequences from portal area 2B had two different rearrangements. One rearrangement was present both in the portal area 2A and portal area 2B. CONCLUSION: The oligoclonal B cell proliferation and stepwise accumulation of somatic mutations suggested that an antigen-driven B cell response had occurred in the portal area of PBC.


Assuntos
Linfócitos B/imunologia , Região Variável de Imunoglobulina/genética , Cirrose Hepática Biliar/imunologia , Cirrose Hepática Biliar/patologia , Fígado/imunologia , Fígado/patologia , Idoso , Linfócitos B/citologia , Sequência de Bases , Divisão Celular/imunologia , Epitopos , Feminino , Humanos , Pessoa de Meia-Idade , Dados de Sequência Molecular , Plasmócitos/citologia , Plasmócitos/imunologia , Reação em Cadeia da Polimerase
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