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1.
Front Vet Sci ; 10: 1297221, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38026620

RESUMO

Saracatinib/AZD0530 (SAR), a Src tyrosine kinase inhibitor, mitigates seizure-induced brain pathology in epilepsy models upon repeated oral dosing. However, repeated dosing is stressful and can be challenging in some seizing animals. To overcome this issue, we have incorporated SAR-in-Diet and compared serum pharmacokinetics (PK) and brain concentrations with conventional repeated oral dosing. Saracatinib in solution or in-diet was stable at room temperature for >4 weeks (97 ± 1.56%). Adult Sprague Dawley rats on SAR-in-Diet consumed ~1.7 g/day less compared to regular diet (16.82 ± 0.6 vs. 18.50 ± 0.5 g/day), but the weight gain/day was unaffected (2.63 ± 0.5 g/day vs. 2.83 ± 0.2 g/day). Importantly, we achieved the anticipated SAR dose range from 2.5-18.7 mg/kg of rat in response to varying concentrations of SAR-in-Diet from 54 to 260 ppm of feed, respectively. There was a strong and significant correlation between SAR-in-Diet dose (mg/kg) and serum saracatinib concentrations (ng/ml). Serum concentrations also did not vary significantly between SAR-in-Diet and repeated oral dosing. The hippocampal saracatinib concentrations derived from SAR-in-Diet treatment were higher than those derived after repeated oral dosing (day 3, 546.8 ± 219.7 ng/g vs. 238.6 ± 143 ng/g; day 7, 300.7 ± 43.4 ng/g vs. 271.1 ± 62.33 ng/g). Saracatinib stability at room temperature and high serum and hippocampal concentrations in animals fed on SAR-in-Diet are useful to titer the saracatinib dose for future animal disease models. Overall, test drugs in the diet is an experimental approach that addresses issues related to handling stress-induced variables in animal experiments.

2.
Amino Acids ; 55(12): 1803-1817, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37389730

RESUMO

In the combat of treating cancer recent therapeutic approaches are focused towards enzymatic targets as they occupy a pivotal participation in the cascade of oncogenesis and malignancy. There are several enzymes that modulate the epigenetic pathways and chromatin structure related to cancer mutation. Among several epigenetic mechanisms such as methylation, phosphorylation, and sumoylation, acetylation status of histones is crucial and is governed by counteracting enzymes like histone acetyl transferase (HAT) and histone deacetylases (HDAC) which have contradictory effects on the histone acetylation. HDAC inhibition induces chromatin relaxation which forms euchromatin and thereby initiates the expression of certain transcription factors attributed with apoptosis, which are mostly correlated with the expression of the p21 gene and acetylation of H3 and H4 histones. Most of the synthetic and natural HDAC inhibitors elicit antineoplastic effect through activation of various apoptotic pathways and promoting cell cycle arrest at various phases. Due to their promising chemo preventive action and low cytotoxicity against normal host cells, bioactive substances like flavonoids, alkaloids, and polyphenolic compounds from plants have recently gained importance. Even though all bioactive compounds mentioned have an HDAC inhibitory action, some of them have a direct effect and others enhance the effects of the standard well known HDAC inhibitors. In this review, the action of plant derived compounds against histone deacetylases in a variety of in vitro cancer cell lines and in vivo animal models are articulated.


Assuntos
Antineoplásicos , Neoplasias , Animais , Histonas/metabolismo , Histona Desacetilases/genética , Histona Desacetilases/metabolismo , Histona Desacetilases/uso terapêutico , Inibidores de Histona Desacetilases/farmacologia , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Cromatina , Neoplasias/tratamento farmacológico , Neoplasias/genética , Compostos Fitoquímicos , Acetilação
3.
Exp Parasitol ; 239: 108304, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35690094

RESUMO

Chemical acaricides are widely used for the effective control of ticks in India. The synthetic pyrethroids, are one of the most popular chemical acaricides with selective neurotoxic potential. Flumethrin is a type II synthetic pyrethroid used extensively in veterinary practice in India. The present study was undertaken to evaluate the cytotoxic effects of flumethrin on the engorged females of Rhipicephalus annulatus using entomological parameters, histology, electron microscopy and relative quantification of receptors of dopamine and GABAB mRNAs. Adult immersion test (AIT) using flumethrin (100 ppm), revealed twenty per cent mortality of ticks, hundred per cent inhibition of fecundity and complete blocking of hatching of the laid eggs. Microscopic analysis of the structure of the ovaries after 24 h of treatment with flumethrin (90 ppm) revealed changes, viz., reduction in size with the presence of amorphous material inside stage I oocytes, wrinkled boundary and chromatin fragmentation of nucleus of stage II oocytes, vacuoles around the germinal vesicle, thickening of the nuclear membrane and chromatin clumping of stage III oocytes and reduction in size and shape of mature stage IV and V oocytes. Also, a large number of vacuoles were observed throughout the pedicel cell region of stage II and III oocytes. Ultrastructurally, irregular nuclear membrane, swelling as well as crystolysis of mitochondria and detachment of external and internal layers of the basal lamina of oocytes were the major structural alterations confirming direct damaging effects of flumethrin on the germinative cells. The relative quantification of the expression of dopamine D1, dopamine D2 and GABAB receptors by quantitative real-time PCR (qRT PCR), revealed the upregulation of dopamine D1 receptor and downregulation of receptors of dopamine D2 and GABAB in the ovary of treated ticks.


Assuntos
Acaricidas , Piretrinas , Rhipicephalus , Acaricidas/farmacologia , Animais , Cromatina , Dopamina/farmacologia , Feminino , Piretrinas/farmacologia , Ácido gama-Aminobutírico/farmacologia
4.
Nat Prod Res ; 35(24): 6216-6222, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33096964

RESUMO

Effect of Moringa oleifera, an age-old ingredient of Indian ayurvedic and traditional medicine, was tested for its effect on age related antioxidant activity in Wistar albino rats of three age groups (6, 12 and 18 months old). Aqueous extract of M. oleifera leaves (MOAE) was administered orally at a dosage of 200 mg/kg body weight for a period of 30 days. MOAE treatment showed significant reduction in lipid peroxidation and lipofuscin pigmentation along with elevated serotonin and antioxidant enzymes in the brains of treated groups of aged rats. LC-MS-MS analysis revealed blood brain barrier permeable secondary metabolites viz., 9,9-bianthracene, 4-Methoxycinnamic acid, Cinnamic acid, (E)-p-coumaric acid pyrogallol and ostruthin from the extract. 9,9-bianthracene and ostruthin showed better binding affinity to Keap-1 and SERT in silico. The present result suggests the protective efficacy of M oleifera against age related oxidative stress in brain.


Assuntos
Moringa oleifera , Envelhecimento , Animais , Antioxidantes/farmacologia , Extratos Vegetais/farmacologia , Folhas de Planta , Ratos , Ratos Wistar
5.
Exp Parasitol ; 204: 107732, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31374184

RESUMO

In the present study, the cytotoxic effects of amitraz, an octopamine receptor agonist on the reproductive system of engorged adult females of Rhipicephalus (Boophilus) annulatus were assessed using histology, electron microscopy and octopamine beta (OCTß) receptor transcriptional expression analysis. Adult immersion test (AIT) was performed by immersing the fully engorged female ticks for 2 min in different concentrations of amitraz (200, 250, 300, 350 ppm). Amitraz at the dose of 300 ppm, caused an adult tick mortality of 16.66 ±â€¯6.80 per cent, inhibition of fecundity of 75.80 per cent and hatching of 50 per cent of ova laid by treated ticks. Histological changes in the ovaries of ticks collected after 24 h of treatment with amitraz (300 ppm), in comparison with controls (distilled water/methanol) were identified by microscopical examination of sections (4  µm) stained using haematoxylin and eosin. These changes included reduction in size and basophilia of stage I oocytes, presence of cytoplasmic vacuoles of various sizes around germinal vesicle of stage II oocytes, wavy basement membrane of stage III oocytes and reduction in size and number of mature stage IV and V oocytes. Electron microscopy was employed for understanding the structural changes in the ultrathin sections (60 nm) of ovaries. Ticks treated with amitraz showed major ultrastructural changes such as irregular nuclear membrane, crystolysis of mitochondria and detachment of external and internal layers of basal lamina of oocytes. The cDNA synthesized from the total RNA of whole ticks and ovaries of ticks treated with amitraz along with controls were used for relative quantification of Octopamine ß receptor (OCTß-R) expression based on the 2-ΔΔCT method by quantitative real time PCR (qRT PCR). Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) was used as endogenous control. Down regulation of expression of OCTß-R mRNA in the ovaries of amitraz treated ticks was observed compared to controls. Thus, the inhibition of fecundity observed in the ticks treated with amitraz can be attributed to the major structural changes and decreased expression of OCT ß receptor mRNA induced by it in the ovary.


Assuntos
Inseticidas/farmacologia , Rhipicephalus/efeitos dos fármacos , Toluidinas/farmacologia , Análise de Variância , Animais , Membrana Basal/efeitos dos fármacos , Membrana Basal/ultraestrutura , Regulação para Baixo , Feminino , Fertilidade/efeitos dos fármacos , Expressão Gênica , Microscopia Eletrônica de Transmissão , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/ultraestrutura , Oócitos/efeitos dos fármacos , Oócitos/ultraestrutura , Ovário/anatomia & histologia , Ovário/efeitos dos fármacos , Ovário/ultraestrutura , Oviposição/efeitos dos fármacos , RNA Mensageiro/isolamento & purificação , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Receptores de Amina Biogênica/agonistas , Receptores de Amina Biogênica/efeitos dos fármacos , Rhipicephalus/anatomia & histologia , Rhipicephalus/genética , Rhipicephalus/ultraestrutura , Espectrofotometria , Controle de Ácaros e Carrapatos/métodos , Vacúolos/efeitos dos fármacos , Vacúolos/ultraestrutura
6.
Asian J Neurosurg ; 13(3): 873-876, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30283571

RESUMO

Atypical teratoid rhabdoid tumor (ATRT) is a rare, highly malignant tumor of the central nervous system, commonly affecting children below 3 years of age, with around 300 cases reported in the literature. Suprasellar area is a very rare location for such tumor in the pediatric population, with technical difficulties in complete excision. Third ventricular ATRT is very rare. Here, we report the case of a 2-year-old male child who presented with lethargy and vomiting. He had features of raised intracranial pressure with reduced vision in both eyes. Magnetic resonance imaging of the brain revealed a heterogeneously enhancing lobulated giant lesion in the suprasellar location, occupying the third ventricle and hypothalamus with encasement of both carotids. He underwent pericoronal parasagittal craniotomy, interhemispheric transcallosal interforniceal approach and gross total excision of the lesion. Postoperatively, the child had altered sensorium and diabetes insipidus, both of which recovered over a span of 10 days. Histopathological examination of the specimen was consistent with the diagnosis of World Health Organization Grade IV ATRT. In spite of all our efforts, he succumbed to his illness 5 months postoperatively.

7.
Vet Parasitol ; 247: 113-120, 2017 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-29080757

RESUMO

The present study utilizes the ultrastructural analysis of the fully engorged female Rhipicephalus (Boophilus) annulatus ticks, as a tool to evaluate the cytotoxic potential of deltamethrin and amitraz on the germinative cells. The ultrastructural analysis of the ovary of the normal (untreated) R (B.) annulatus revealed, oocytes in different stages of development, attached to the ovary wall by pedicel cells. The attachment site of oocyte to the pedicel cell was characterized by indentations of the plasma membrane. The oocyte was bound by three cell membranes viz., plasma membrane, chorion and basal lamina. The stages of oocytes were differentiated ultrastructurally based on the features of their outer membrane and the number and size of lipid and yolk droplets. Detailed day wise analysis of ultrastructural changes in the ovary during the post-engorgement period revealed the occurrence of the degenerative changes from day five onwards. These appeared first in the oocytes followed by the germinal epithelium. The ovary of ticks treated with methanol (control), revealed similar topographies as that of a normal ovary except for the presence of very few oocytes with ring shaped nucleoli. Ultrastructurally, treatment with deltamethrin produced more prominent and extensive morphological alterations when compared to amitraz. In the case of ticks treated with amitraz, the oocytes of stage IV and V showed wavy and disrupted outer boundaries along with the loss of integrity of the yolk droplets. Uneven nuclear membranes of stage II oocytes and cristolysis of mitochondria of mature oocytes were the other changes noticed. Ticks treated with deltamethrin revealed prominent modifications such as, detachment of the basal lamina, wrinkled boundary, inconsistent nuclear membrane, ring shaped nucleoli and chromatin clumping in the case of the early stage oocytes (I and II), whereas swelling and cristolysis of mitochondria were seen in mature oocytes. The study further indicated that, in addition to the previous proven neurotoxic effects, these compounds act directly on the ovary of tick.


Assuntos
Acaricidas/farmacologia , Nitrilas/farmacologia , Piretrinas/farmacologia , Rhipicephalus/ultraestrutura , Infestações por Carrapato/veterinária , Toluidinas/farmacologia , Animais , Feminino , Microscopia Eletrônica de Transmissão/veterinária , Oócitos/efeitos dos fármacos , Oócitos/ultraestrutura , Ovário/efeitos dos fármacos , Ovário/ultraestrutura , Rhipicephalus/efeitos dos fármacos , Infestações por Carrapato/tratamento farmacológico , Infestações por Carrapato/parasitologia
11.
ScientificWorldJournal ; 2015: 126584, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25664337

RESUMO

The present communication describes the detailed day wise study of histological changes of the ovary of Rhipicephalus (Boophilus) annulatus in the postengorgement period together with the systematic classification of their oocytes. The ovary of R. (B.) annulatus is panoistic type with an asynchronous development of oocytes. All the stages (II, III, IV, and V) of oocytes except stage I were similar to R. (B.) microplus. The stage I oocytes showed basophilia, which was not reported earlier in other species of ticks. Day wise changes were in the form of presence of oogonia in partially fed and day one engorged adults, considerable degeneration of oocytes on day two, emergence of new wave of oocytes on day three, presence of mature oocytes up to day eight, and complete degeneration of ovarian tissue from day eight onwards. The degenerative changes in the ovary appeared initially in the oocytes followed by germinal epithelium.


Assuntos
Rhipicephalus/anatomia & histologia , Animais , Ingestão de Alimentos/fisiologia , Feminino , Oócitos/fisiologia , Ovário/anatomia & histologia , Ovário/fisiologia , Rhipicephalus/fisiologia
12.
ScientificWorldJournal ; 2014: 715481, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25436226

RESUMO

The acaricidal activity of the petroleum ether extract of leaves of Tetrastigma leucostaphylum (Dennst.) Alston (family: Vitaceae) against Rhipicephalus (Boophilus) annulatus was assessed using adult immersion test (AIT). The per cent of adult mortality, inhibition of fecundity, and blocking of hatching of eggs were studied at different concentrations. The extract at 10% concentration showed 88.96% inhibition of fecundity, 58.32% of adult tick mortality, and 50% inhibition of hatching. Peak mortality rate was observed after day 5 of treatment. Mortality of engorged female ticks, inhibition of fecundity, and hatching of eggs were concentration dependent. The LC50 value of the extract against R. (B.) annulatus was 10.46%. The HPTLC profiling of the petroleum ether extract revealed the presence of at least seven polyvalent components. In the petroleum ether extract, nicotine was identified as one of the components up to a concentration of 5.4%. However, nicotine did not reveal any acaricidal activity up to 20000 ppm (2%). Coconut oil, used as diluent for dissolving the extract, did not reveal any acaricidal effects. The results are indicative of the involvement of synergistic or additive action of the bioactive components in the tick mortality and inhibition of the oviposition.


Assuntos
Acaricidas/farmacologia , Alcanos/farmacologia , Extratos Vegetais/farmacologia , Rhipicephalus/efeitos dos fármacos , Vitaceae , Acaricidas/isolamento & purificação , Alcanos/isolamento & purificação , Animais , Feminino , Extratos Vegetais/isolamento & purificação
13.
Biomed Res Int ; 2014: 630160, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24971339

RESUMO

A very high prevalence of microfilaremia of 42.68 per cent out of 164 canine blood samples examined was observed in Cherthala (of Alappuzha district of Kerala state), a known human Brugia malayi endemic area of south India. The species of canine microfilariae were identified as Dirofilaria repens, Brugia malayi, and Acanthocheilonema reconditum. D. repens was the most commonly detected species followed by B. pahangi. D. immitis was not detected in any of the samples examined. Based on molecular techniques, microfilariae with histochemical staining pattern of "local staining at anal pore and diffuse staining at central body" was identified as D. repens in addition to those showing acid phosphatase activity only at the anal pore. Even though B. malayi like acid phosphatase activity was observed in few dogs examined, they were identified as genetically closer to B. pahangi. Hence, the possibility of dogs acting as reservoirs of human B. malayi in this area was ruled out.


Assuntos
Brugia Malayi/fisiologia , Doenças do Cão/epidemiologia , Doenças do Cão/parasitologia , Doenças Endêmicas/veterinária , Filariose/parasitologia , Filariose/veterinária , Fosfatase Ácida/metabolismo , Animais , Cruzamento , Cães , Doenças Endêmicas/estatística & dados numéricos , Feminino , Filariose/epidemiologia , Humanos , Índia/epidemiologia , Masculino , Microfilárias/citologia , Dados de Sequência Molecular , Filogenia , Prevalência
14.
J Neurosurg Anesthesiol ; 26(1): 17-21, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23632431

RESUMO

BACKGROUND: Transient lower cranial nerve deficits may occur after surgery in the posterior cranial fossa. Stridor has been reported after cerebellopontine angle epidermoid resection. The aim of this retrospective study is to find out whether any preoperative, intraoperative, and postoperative factors lead to stridor after resection of vestibular schwannoma. METHODS: Data of patients who underwent vestibular schwannoma resection from 2006 to 2011 were collected. We collected the following factors--age, sex, weight, diabetes, hypertension, preoperative cranial nerve deficits, tumor characteristics, intraoperative use of nitrous oxide, difficult endotracheal intubation, duration of surgery, postoperative cough and swallowing difficulty, limb weakness, and facial edema. Data of patients who developed stridor were compared with those who did not develop stridor. Odds ratio (OR) was used to assess the risk of developing stridor with each factor. RESULTS: Thirteen patients (4.65%) developed stridor in immediate postextubation period. The risk of stridor was significantly high in patients who had difficult intubation (OR=9.56), longer duration of surgery (P=0.034) and in patients who developed facial edema (OR=13.33), upperlimb weakness (OR=32.88), poor cough (OR=7.72), and swallowing difficulty (OR=24.97) in the postoperative period. CONCLUSIONS: The identification of the exact etiology of stridor often is difficult. Our results suggest that stridor may be more likely in patients who were difficult to intubate, had longer duration of surgery, who develop facial and neck edema and upperlimb weakness, poor cough, and swallowing after surgery. Establishing airway patency with intubation of the trachea may be required if patients develop oxygen desaturation due to stridor.


Assuntos
Neuroma Acústico/cirurgia , Procedimentos Neurocirúrgicos/métodos , Complicações Pós-Operatórias/epidemiologia , Sons Respiratórios , Adulto , Extubação , Ângulo Cerebelopontino/cirurgia , Edema/complicações , Nervo Facial/fisiopatologia , Feminino , Humanos , Hipóxia/etiologia , Intubação Intratraqueal/efeitos adversos , Intubação Intratraqueal/métodos , Masculino , Pessoa de Meia-Idade , Debilidade Muscular/complicações , Neuroma Acústico/patologia , Complicações Pós-Operatórias/prevenção & controle , Respiração Artificial/estatística & dados numéricos , Estudos Retrospectivos , Fatores de Risco , Traqueostomia , Paralisia das Pregas Vocais/epidemiologia , Paralisia das Pregas Vocais/etiologia
15.
Ticks Tick Borne Dis ; 2(3): 160-2, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21890070

RESUMO

The current need of identification of a new acaricidal agent which is acceptable to public as environmentally safe is a daring task. Use of herbal acaricides is such an alternative. Most of the herbal extracts or fractions are dissolved in polar or non-polar solvents or detergents before tested for acaricidal activity. The solvent or detergent to be used for dissolving the herbal extract should be of little acaricidal activity. In the present study, experimentations were carried out on adult engorged female ticks to detect the toxicity of different solvents, viz. hexane, petroleum ether, n-butanol, isopropyl alcohol, chloroform, glycerol, ethyl acetate, acetone, ethanol, and methanol. The study revealed that methanol was the least toxic solvent against Rhipicephalus (Boophilus) annulatus.


Assuntos
Acaricidas , Vetores Aracnídeos/efeitos dos fármacos , Metanol/farmacologia , Rhipicephalus/efeitos dos fármacos , Solventes/farmacologia , Animais , Vetores Aracnídeos/fisiologia , Feminino , Interações Hidrofóbicas e Hidrofílicas , Contagem de Ovos de Parasitas , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Rhipicephalus/fisiologia
16.
Vet Parasitol ; 179(1-3): 287-90, 2011 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-21440993

RESUMO

The crude ethanolic extract of aerial parts of Leucas aspera was tested for its acaricidal properties against Rhipicephalus (Boophilus) annulatus. The per cent adult mortality, inhibition of fecundity and hatching of laid ova were studied at concentrations of 1.56, 3.13, 6.25, 12.5, 25, 50 and 100mg/ml. Adult tick mortality was significant at the highest concentration tested. Inhibition of fecundity of treated groups differed significantly from control and was concentration dependent. L. aspera extract also produced complete failure of eclosion of eggs from the treated ticks even at lower dilutions of the extract.


Assuntos
Acaricidas/farmacologia , Lamiaceae/química , Extratos Vegetais/farmacologia , Rhipicephalus/efeitos dos fármacos , Acaricidas/química , Animais , Relação Dose-Resposta a Droga , Feminino , Fertilidade/efeitos dos fármacos , Extratos Vegetais/química
17.
Neurol India ; 58(3): 429-35, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20644273

RESUMO

PURPOSE: Choroid plexus tumors (CPT) are rare neoplasms that pose considerable treatment challenges. This study reviews a single institute's experience with 25 patients of CPT and attempts to contribute to the general body of knowledge on CPT. MATERIALS AND METHODS: A retrospective analysis of the case records of 25 patients operated for CPT since January 1998 and having a minimum of 1 year follow-up. RESULTS: The study group included 12 (48%) cases of choroid plexus papilloma (CPP), 09 (36%) cases of choroid plexus carcinoma (CPC) and 4 cases of atypical CPP. The mean age at presentation was 18.6 years (range, 6 months to 54 years; SD, 18.7) and a male preponderance was noted (17:8). Raised intracranial pressure was the commonest presenting symptom (72%). The tumors were distributed as follows: lateral ventricle (16; 64%), fourth ventricle (5; 20%), fourth ventricle with cerebellopontine angle extension (3; 12%), and third ventricle (1; 4%). A complete surgical excision was achieved in 11 cases of CPP and 8 cases of CPC. Operative complications include pneumocephalus (40%), focal deficits (36%), subdural effusion (32%), and persistent hydrocephalus requiring shunt (24%). All patients with CPP had a good outcome at the end of a mean follow-up of 5.4 years, whereas the median survival for patients with CPCs who underwent a subtotal resection with adjuvant therapy was 36 months. CONCLUSION: CPTs include a spectra ranging from CPP to CPC. Radiologic and histologic characterization of these tumors is difficult and newer immunohistochemical and genetic studies should be done to differentiate them from each other. Total excision offers a good prognosis and should be attempted for all forms of CPTs. CPPs carry a good prognosis, and adjuvant therapy is not indicated even after partial excision. CPCs and atypical CPCs carry a poor prognosis, and adjuvant therapy improves survival marginally after total excision. Spinal drop metastases are common for CPC and screening of the spine for possible metastasis should be part of the routine preoperative and postoperative investigation protocol.


Assuntos
Neoplasias do Plexo Corióideo/terapia , Terapia Combinada/métodos , Adolescente , Adulto , Criança , Pré-Escolar , Neoplasias do Plexo Corióideo/classificação , Neoplasias do Plexo Corióideo/patologia , Feminino , Seguimentos , Humanos , Lactente , Prática Institucional/estatística & dados numéricos , Angiografia por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos , Resultado do Tratamento , Adulto Jovem
18.
J Magn Reson Imaging ; 29(4): 967-70, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19306444

RESUMO

PURPOSE: To explore the utility of diffusion tensor imaging (DTI) and diffusion tensor metrics (DTM) in characterizing the structural pathology of epidermoid cysts. DTI gives information about the tissue structure; a high fractional anisotropy (FA) indicates a highly structured orientation of the tissue, fibers, or white matter tracts. Based on the tensor rank, a set of three metrics has been described that can be used to measure the directional dependence of diffusion: linear anisotropy (CL), planar anisotropy (CP), and spherical anisotropy (CS). DTM takes into account the shape of diffusion anisotropy and hence may provide better insight into the orientation of structures than FA. MATERIALS AND METHODS: DTI was performed in three patients with epidermoid cysts. FA, directionally-averaged mean diffusivity (Dav), exponential apparent diffusion coefficient (eADC), and DTM, such as CL, CP, and CS, were measured from the tumor core as well as from the normal-appearing white matter. Histopathological correlation was obtained. RESULTS: Epidermoid cysts showed high FA with Dav values similar to that of normal white matter. eADC maps did not show any restriction of diffusion. FA values were high, but not as high as that for the white matter. CP values were higher and CL values were lower than those obtained for the white matter in various regions. CONCLUSION: High CP values suggest preferential diffusion of water molecules along a two-dimensional geometry, which could be attributed to the well-structured orientation of keratin filaments and flakes within the tumor as demonstrated by histopathology. Advanced imaging modalities like DTI with DTM can provide information regarding the microstructural anatomy of the epidermoid cysts.


Assuntos
Encefalopatias/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Cisto Epidérmico/patologia , Humanos , Processamento de Imagem Assistida por Computador
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