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2.
J Biomed Phys Eng ; 11(1): 39-46, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33564638

RESUMO

BACKGROUND: Some brain tumors such as ependymoma and Medulloblastoma have similar MR images which may result to undifferentiated them from each other. OBJECTIVE: This study aimed to compare the apparent diffusion coefficient (ADC) of two different cerebellar pediatric tumors, including ependymoma and medulloblastoma which have shown similar clinical images in conventional magnetic resonance imaging (MRI) methods. MATERIAL AND METHODS: In this analytical study, thirty six pediatric patients who were suspected to have the mentioned tumors according to their CT image findings were included in this study. The patients were subjected to conventional MRI protocols followed by diffusion weighted imaging (DWI) and ADC values of the tumors were calculated automatically using MRI scanner software. RESULTS: The mean (± SD) ADC value for ependymoma (1.2± 0.06 ×10-3 mm2/s) was significantly higher than medulloblastoma (0.87 ± 0.02 ×10-3 mm2/s) (p = 0.041). Moreover, the maximum ADC value of ependymoma was considerably different in comparison with medulloblastoma (1.4 ×10-3 mm2/s and 0.96×10-3 mm2/s, respectively; p = 0.035). Furthermore, the minimum ADC value of ependymoma was higher compared to medulloblastoma (1.0 ×10-3 mm2/s and 0.61×10-3 mm2/s, respectively), but there was not significant (p = 0.067). CONCLUSION: Evaluation of ADC values for ependymoma and medulloblastoma is a reliable method to differentiate these two malignancies. This is due to different ADC values reflected during the evaluation.

3.
Arch Razi Inst ; 75(3): 317-325, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33025772

RESUMO

Ticks are reservoir hosts of pathogenic Rickettsia in humans and domestic animals. Most pathogenic Rickettsia species belong to the spotted fever group (SFG). The present study aimed to determine the tick species infected with Rickettsia based on the genus-specific 23S ribosomal ribonucleic acid (rRNA), 16S rRNA, and citrate synthase (gltA) gene fragments. A total of 61 tick specimens were selected for molecular assay and 12 samples for sequencing. Phylogenetic analysis was conducted using neighbor-joining and Bayesian inference methods. Argas persicus, Haemaphysalis sulcata, Ha. inermis, and Hyalomma asiaticum were infected by spotted fever Rickettsia. The SFG is the main group of Rickettsia that can be detected in the three genera of ticks from Iran.


Assuntos
Argas/microbiologia , Proteínas de Bactérias/análise , Ixodidae/microbiologia , RNA Bacteriano/análise , Rickettsia/isolamento & purificação , Animais , Citrato (si)-Sintase/análise , Irã (Geográfico) , Filogenia , RNA Ribossômico 16S/análise , RNA Ribossômico 23S/análise , Rickettsia/classificação , Rickettsia/enzimologia , Rickettsia/genética , Rickettsiose do Grupo da Febre Maculosa/microbiologia
4.
Arch Razi Inst ; 75(1): 39-46, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32292001

RESUMO

The present study was conducted as the first molecular detection of Anaplasma species in tick samples based on the sequencing of major surface proteins 4 (msp4) gene fragments in different parts of Iran. A total of 130 tick specimens were collected from Hormozgan, Lorestan, and Guilan, Iran, within 2015 to 2017. Hyalomma asiaticum, Hyalomma dromedarii, Rhipicephalus sanguineus, and Rhipicephalus (Boophilus) species were identified in different geographical regions. An amplicon of 464-bp msp4 of Anaplasma was amplified using polymerase chain reaction in various tick species. Three sequences, including one Anaplasma marginale from R. (Boophilus) species and two Anaplasma ovis from Rhipicephalus sanguineus, were obtained after sequencing. It is concluded that bovine and ovine anaplasmosis agents are present in tick samples in Iran. The use of the gene families of six major surface proteins for the detection of various Anaplasma species is recommended.


Assuntos
Anaplasma marginale , Anaplasma ovis , Ixodidae , Animais , Anaplasma marginale/isolamento & purificação , Anaplasma ovis/isolamento & purificação , Irã (Geográfico) , Ixodidae/microbiologia , Reação em Cadeia da Polimerase , Rhipicephalus/microbiologia , Rhipicephalus sanguineus/microbiologia
5.
Eur Ann Allergy Clin Immunol ; 52(3): 104-111, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31702121

RESUMO

Summary: Objective.There are different diagnostic criteria for the diagnosis of Allergic bronchopulmonary aspergillosis (ABPA) in CF patients. In this present study we evaluated the prevalence of ABPA in Iranian CF patients by two more usual diagnostic criteria as ISHAM working criteria (A) and CF Foundation Consensus Conference criteria (B). Methods.Eighty-six CF patients were included in the study. All CF patients underwent for Aspergillus skin prick test (AST), Aspergillus-specific IgE (sIgEAf) and Aspergillus-specific IgG (sIgGAf), total IgE. The ABPA prevalence was estimated by two diagnostic criteria, (A) and (B) and compared. Results. The frequency of positive AST, total IgE, sIgEAf and sIgGAf were 47 (54.6%), 9 (10.5%), 42 (48.8%) and 67 (77.9%), respectively. The obtained rate of ABPA prevalence (10.5%) was identical in two diagnostic criteria A and B (kappa value of 1.000). Conclusions.The applied diagnostic criteria had no significant effect on the reported rate of ABPA prevalence.


Assuntos
Aspergilose Broncopulmonar Alérgica/epidemiologia , Aspergillus fumigatus/fisiologia , Fibrose Cística/epidemiologia , Adolescente , Adulto , Criança , Pré-Escolar , Fibrose Cística/diagnóstico , Feminino , Humanos , Imunoglobulina E/sangue , Lactente , Irã (Geográfico)/epidemiologia , Masculino , Prevalência , Testes Cutâneos , Adulto Jovem
6.
Anal Chim Acta X ; 2: 100009, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33117976

RESUMO

This study assessed the solute permeability of a family of UV and moisture cured acrylates-based adhesives during in vitro ageing in pH 7.4 buffer. Acrylates have a potential role in bone fracture fixation, but their inability to allow microsolute exchange between the fractured bone surfaces may contribute to ineffective healing. Cyclic voltammetry and chronoamperometry were used to determine the diffusion coefficients for various electrochemically active probe molecules (O2, H2O2, acetaminophen, catechol, uric acid and ascorbic acid) at proprietary acrylic, urethane - acrylate and cyanoacrylate adhesives. All adhesives proved to be impermeable for up to 9 days ageing, following which a near-exponential increase in permeability resulted for all solutes. At 18 days, the diffusion coefficients were in the range of 10-5 cm2s-1 for O2 and H2O2 and 10-6 cm2s-1 for the organic solutes; no transport selectivity was seen between the latter. Adhesive joint strength showed a direct, inverse, correlation with permeability, with the more hydrophilic cyanoacrylates showing the greatest loss of strength. Adhesive permeabilisation does not appear to be compatible with the retention of bonding strength, but it serves as a new non-destructive predictor of adhesion strength change during ageing and practical use.

7.
J Biomed Phys Eng ; 8(1): 65-72, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29732341

RESUMO

BACKGROUND: Radiotherapy with large mantle field is an effective technique in increasing the risk of secondary cancers among HL (Hodgkin Lymphoma) patients; therefore, it is essential to choose an effective treatment field including the least medical conditions in radiotherapy. OBJECTIVE: The present study aimed to plan separate fields for neck and mediastinum using various energies, to compare dose distribution with MLC and to block field formation. MATERIALS AND METHODS: In this study, 3D conformal treatments, Siemens Oncor accelerator equipped with multi-leaf collimator (MLC) were performed to create anterior-posterior fields. CT-scan data of 18 female patients with neck and mediastinal involvement was imported in TIGRT treatment planning system, and then treatment plans were introduced. RESULTS AND CONCLUSION: Using treatment plan 1, photon 6 MV in neck weighting 1 from interior, 0.5 from posterior, photon 18MV in mediastinum weighting 1 from interior and 0.5 from posterior, it was shown that regarding the common treatment plan used with photon 6 MV, mean dose delivered to breast, lung, esophagus and larynx reduced 6, 7, 41 and 10 percent, respectively and uniformity index improved by 10 percent. Using block compared to MLC in all treatment plans offered improved average dose in all organs under study. To protect breast and lung while using MLC and block in the first treatment plan seemed to be more appropriate; however, using blocks in comparison to MLC increased delivered mean dose in all organs under study. Using separate fields with Pb blocks, though, showed smaller increase.

8.
Iran J Vet Res ; 18(3): 208-211, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29163651

RESUMO

The aim of this study was to identify virulence genes and antimicrobial resistance of Escherichia coli isolated from bovine clinical mastitis in dairy herds in Iran. Sampling was done from 86 inflamed quarters of dairy cows in 8 commercial farms of Alborz province, Iran in summer 2015. Shiga toxin-producing E. coli (STEC) virulence genes were detected by multiplex PCR and multi-drug resistance profiles were confirmed using disk diffusion method. Among 60 E. coli isolated from examined samples, 13 (21.6%) of them were STEC. The results of PCR assay showed that eaeA gene was carried by 4 (30.8%) of STEC isolates. Although stx1 in combination with eaeA gene was detected from 7 (53.8%) of STEC isolates, stx1 and stx2 genes were detected from only 1 (7.7%) of the examined samples. The result of the disk diffusion method showed that all E. coli isolates were resistant to penicillin, tylosin, oxytetracycline, erythromycin, ampicillin, streptomycin and neomycin. However all isolates were susceptible to enrofloxacin. Therefore, according to the results establishing a regular monitoring system for identification of cases with clinical mastitis and conducting antibiotic sensitivity tests are recommended.

9.
Brachytherapy ; 16(3): 497-502, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28190784

RESUMO

PURPOSE: The quality of a low-dose rate prostate brachytherapy implant depends on the accurate placement of sources in their planned locations. This study investigates intraoperative factors that potentially contribute to stranded source placement inaccuracy in prostate brachytherapy. METHODS AND MATERIALS: Intraoperative video images of the brachytherapist's hand motions and needle insertions during the implant procedure were acquired for analysis. Using video analysis software, maximum and average needle insertion velocities were determined. The number of needle insertion attempts and the use of the brachytherapist's other hand to manipulate the needle direction were also recorded. Sources misplacements were analyzed using an ultrasound-based method described elsewhere. RESULTS: Fifteen patients agreed to undergo this study; 1619 125I seeds were inserted using 357 needles; 1197 seeds were confidently identified using ultrasound images and included in the analysis. The mean overall misplacement was 0.49 cm (0-2 cm, 95% CI = 0.47-0.51); 614 seeds were delivered with a single pass and 583 seeds with >1 passes (range 2-6). The mean maximum needle velocity was 12.34 cm s-1 (range 4-28 cm s-1) and mean average velocity was 4.76 cm s-1 (range 0.4-17.4 cm s-1); 747 seeds were delivered with manipulation of the needle. The generalized linear model test was used to analyze factors contributing to seed misplacement, and it was found that a maximum speed <12 cm s-1 was associated with a decrease in seed misplacement by 0.049 cm vs. a maximum speed >12 cm s-1, p = 0.0121). Other evaluated factors were found to have no statistically significant correlation with seed misplacement: average speed (p = 0.4947), manual manipulation of needle (p = 0.9264), and number of needle passes (p = 0.8907). CONCLUSIONS: This study identified that needles inserted with lower maximum velocity were associated with less seed misplacement. Manual manipulation of the needle, number of passes, and average speed did not show statistically significant correlation with seed misplacement.


Assuntos
Braquiterapia/métodos , Braquiterapia/normas , Neoplasias da Próstata/radioterapia , Idoso , Humanos , Radioisótopos do Iodo/uso terapêutico , Masculino , Pessoa de Meia-Idade , Agulhas , Neoplasias da Próstata/cirurgia , Próteses e Implantes , Dosagem Radioterapêutica , Ultrassonografia , Gravação em Vídeo
10.
Accid Anal Prev ; 89: 88-94, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26845058

RESUMO

The majority of advances in occupant protection systems for motor vehicle occupants have focused on occupants seated in the front row of the vehicle. Recent studies suggest that these systems have resulted in lower injury risk for front row occupants as compared to those in the second row. However, these findings are not universal. In addition, some of these findings result from analyses that compare groups of front and second row occupants exposed to dissimilar crash conditions, raising questions regarding whether they might reflect differences in the crash rather than the front and second row restraint systems. The current study examines factors associated with injury risk for pairs of right front seat and second row occupants in frontal crashes in the United States using paired data analysis techniques. These data indicate that the occupant seated in the front row frequently experiences the more severe injury in the pair, however there were no significant differences in the rate of occurrence of these events and events where the more severe injury occurs in the second row occupant of the pair. A logistic regression indicated that the likelihood of the more severe injury occurring in the second row seated occupant of the pair increased as crash severity increased, consistent with data from anatomic test dummy (ATD) tests. It also indicated that the second row occupant was more likely to have the more severe injury in the pair if that occupant was the older occupant of the pair. These findings suggest that occupant protection systems which focus on providing protection specifically for injuries experienced by older occupants in the second row in higher severity crash conditions might provide the greatest benefit.


Assuntos
Acidentes de Trânsito/estatística & dados numéricos , Veículos Automotores/normas , Segurança/normas , Cintos de Segurança/normas , Ferimentos e Lesões/etiologia , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Índices de Gravidade do Trauma , Estados Unidos/epidemiologia , Ferimentos e Lesões/epidemiologia , Adulto Jovem
11.
Handb Clin Neurol ; 126: 275-90, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25410229

RESUMO

Small fiber neuropathy represents a significant component of diabetic sensorimotor polyneuropathy (DSPN) which has to date been ignored in most recommendations for the diagnosis of DSPN. Small fibers predominate in the peripheral nerve, serve crucial and highly clinically relevant functions such as pain, and regulate microvascular blood flow, mediating the mechanisms underlying foot ulceration. An increasing number of diagnostic tests have been developed to quantify small fiber damage. Because small fiber damage precedes large fiber damage, diagnostic tests for DSPN show good sensitivity but moderate specificity, because the gold standard which is used to define DSPN is large fiber-weighted. Hence new diagnostic algorithms for DSPN should acknowledge this emerging data and incorporate small fiber evaluation as a key measure in the diagnosis of DSPN, especially early neuropathy.


Assuntos
Diabetes Mellitus/diagnóstico , Neuropatias Diabéticas/diagnóstico , Eritromelalgia/diagnóstico , Fibras Nervosas/patologia , Animais , Diabetes Mellitus/epidemiologia , Neuropatias Diabéticas/epidemiologia , Diagnóstico Diferencial , Eritromelalgia/epidemiologia , Humanos , Pele/inervação
12.
Diabet Med ; 31(12): 1673-80, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24975286

RESUMO

AIMS: Neuropad is a simple visual indicator test, with moderate diagnostic performance for diabetic peripheral neuropathy. As it assesses sweating, which is a measure of cholinergic small nerve fibre function, we compared its diagnostic performance against established measures of both large and, more specifically, small fibre damage in patients with diabetes. METHODS: One hundred and twenty-seven participants (89 without diabetic peripheral neuropathy and 38 with) aged 57 ± 9.7 years underwent assessment with Neuropad, large nerve fibre assessments: Neuropathy Disability Score, vibration perception threshold, peroneal motor nerve conduction velocity; small nerve fibre assessments: neuropathy symptoms (Diabetic Neuropathy Symptoms score) corneal nerve fibre length and warm perception threshold. RESULTS: Neuropad has a high sensitivity but moderate specificity against large fibre neuropathy assessments: Neuropathy Disability Score (> 2) 70% and 50%, vibration perception threshold (> 14 V) 83% and 53%, and peroneal motor nerve conduction velocity (< 42 m/s) 81% and 54%, respectively. However, the diagnostic accuracy of Neuropad was significantly improved against corneal nerve fibre length (< 14 mm/mm2) with a sensitivity and specificity of 83% and 80%, respectively. Furthermore, the area under the curve for corneal nerve fibre length (85%) was significantly greater than with the Neuropathy Disability Score (66%, P = 0.01) and peroneal motor nerve conduction velocity (70%, P = 0.03). For neuropathic symptoms, sensitivity was 78% and specificity was 60%. CONCLUSIONS: The data show the improved diagnostic performance of Neuropad against corneal nerve fibre length. This study underlines the importance of Neuropad as a practical diagnostic test for small fibre neuropathy in patients with diabetes.


Assuntos
Neuropatias Diabéticas/diagnóstico , Glândulas Sudoríparas/inervação , Adulto , Idoso , Estudos de Casos e Controles , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 2/complicações , Neuropatias Diabéticas/etiologia , Neuropatias Diabéticas/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Condução Nervosa/fisiologia , Percepção/fisiologia , Nervo Fibular/fisiopatologia , Sensibilidade e Especificidade , Glândulas Sudoríparas/fisiopatologia , Sudorese/fisiologia , Vibração
13.
J Parasit Dis ; 38(2): 185-9, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24808649

RESUMO

The aim of study was to necropsy and histopathology evaluation of lung Crenosoma striatum in hedgehog. In July 2012, 10 porcupines were collected from Urmia city and transferred to parasitology lab of the veterinary faculty where they were euthanized by ketamine (over 40-90 mg/kg) intraperitoneally. In this study the lungs were assessed through naked eyes regarding parasite presence upon washing. The lung tissue was examined under loop microscope in order to finding small worms in lung parenchyma. The worms were removed by Anse forceps and kept in AFA solution, and collected for diagnosis. In order to carrying out pathological tests, some samples prepared and placed in formalin 10 % for fixation. The counted worms frequency in high severe and moderate lungs were as 86 (50 females and 36 males) and 19 (13 females and 16 males) worms respectively. But no worms were observed in healthy lungs. The infestation severity was as; low infestation (1-7 worms), moderate infestation (8-20), severe infestation (21-50) and very severe infestation (more than 50 worms). The lung examinations of non-infested lungs indicated that the lung tissues had no parasite. In addition, no inflammation reactions as inflammatory cells presence were observed, and the air spaces with alveoles' wall in some regions were observable. On histopathological examination, the observed alteration was primarily inflammatory changes, and in some cases the proliferation was also observable. Hyperemia and inflammatory cell infiltration, somehow the alveolar space was filled, representing bronchopneumonia reaction. The bronchioles had various changes as hypertrophy and hyperplastic in different parts of respiratory system. Hyperemia and hemorrhage were very severe in some cases caused hemosiderosis in the lung. In severe inflammations the pneumonia along with increasing of bronchial cells in the lumen rose as well, leading to severe verminous infestation of the lung. In regard to the obtained results, the verminous infestation of the porcupines' lung with C. striatum indicated inflammatory and proliferative alteration which was as inflammatory changes in mild cases, and inflammatory and proliferative stances in severe cases.

15.
J Dent (Shiraz) ; 14(2): 68-72, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24724122

RESUMO

STATEMENT OF PROBLEM: Oral premedication used to reduce the anxiety in patients undergoing dental treatment. Passion flower has been used as a sedative that can control the dental anxiety. PURPOSE: This study determines the efficacy of Passion flower, in reducing anxiety during the dental procedures. MATERIAL AND METHODS: In this randomized- one sided blind clinical trial, 63 patients, with moderate, high and severe anxiety(according to VAS score) in need of periodontal treatment were randomly divided into 3 groups of 21.The first group was given the drop Passion flower drop and the second group were given the drop of placebo and the third group; neither drug nor placebo were given (negative control group). RESULTS were analyzed by Chi Square, Variance Analysis, Tucky and Paired-T using SPSS software. RESULTS: Mean anxiety level prior to the drug administration was 12.09±2.42 for the Passion flower group, 12.00±2.66 for the placebo group and 11.66±2.39 for the negative control group. After premedication, these values were: 8.47±2.58 for the Passion flower group, 10.52±2.11 for the placebo group and 11.23±2.34 for the negative control group. These results demonstrated a significant difference (p< 0.0001) in the anxiety levels before and after the Passion flower administration in the Passion flower group and also between the Passion flower group and the other two groups. CONCLUSION: RESULTS indicated that administration of Passion flower, as a premedication, is significantly effective in reducing the anxiety. Since this study is a pioneer on the subject, further trials with greater number of subjects are required to confirm our results.

16.
Genet Mol Res ; 11(4): 3955-60, 2012 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-23212332

RESUMO

Lipoid proteinosis (LP) is a rare autosomal recessive disorder. Classical clinical features include warty skin infiltration, papules on the eyelids, skin scarring, as well as extracutaneous abnormalities such as hoarseness of the voice, epilepsy, and neuropsychiatric abnormalities. A defect in the ECM1 gene is responsible for this disease. A 21-year-old female patient from consanguineous parents (first cousins) was referred to our clinic with many symptoms of LP, such as hoarse voice from infancy, diffuse acneiform scars on her face, and hyperkeratosis on her knees and elbows. The entire ECM1 gene was screened using PCR and sequencing. A novel missense mutation was found in exon 7 of this patient. We report a novel missense mutation in exon 7 of the ECM1 gene found in an Iranian LP patient that causes a C269Y amino acid exchange.


Assuntos
Éxons/genética , Proteínas da Matriz Extracelular/genética , Proteinose Lipoide de Urbach e Wiethe/genética , Mutação de Sentido Incorreto/genética , Erupções Acneiformes/complicações , Erupções Acneiformes/patologia , Sequência de Bases , Feminino , Humanos , Irã (Geográfico) , Masculino , Dados de Sequência Molecular , Linhagem , Adulto Jovem
17.
Med Image Anal ; 15(5): 738-47, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21719344

RESUMO

Diabetic peripheral neuropathy (DPN) is one of the most common long term complications of diabetes. Corneal confocal microscopy (CCM) image analysis is a novel non-invasive technique which quantifies corneal nerve fibre damage and enables diagnosis of DPN. This paper presents an automatic analysis and classification system for detecting nerve fibres in CCM images based on a multi-scale adaptive dual-model detection algorithm. The algorithm exploits the curvilinear structure of the nerve fibres and adapts itself to the local image information. Detected nerve fibres are then quantified and used as feature vectors for classification using random forest (RF) and neural networks (NNT) classifiers. We show, in a comparative study with other well known curvilinear detectors, that the best performance is achieved by the multi-scale dual model in conjunction with the NNT classifier. An evaluation of clinical effectiveness shows that the performance of the automated system matches that of ground-truth defined by expert manual annotation.


Assuntos
Algoritmos , Córnea/inervação , Córnea/patologia , Retinopatia Diabética/patologia , Interpretação de Imagem Assistida por Computador/métodos , Microscopia Confocal/métodos , Fibras Nervosas/patologia , Reconhecimento Automatizado de Padrão/métodos , Humanos , Aumento da Imagem/métodos , Modelos Biológicos , Oftalmoscopia/métodos , Sensibilidade e Especificidade
18.
Diabet Med ; 28(10): 1261-7, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21699561

RESUMO

AIM: We have assessed whether corneal confocal microscopy can be used to detect alterations in nerve morphology following an improvement in risk factors associated with diabetic neuropathy. METHODS: Twenty-five patients with diabetes with mild to moderate neuropathy and 18 control subjects underwent corneal confocal microscopy to quantify corneal nerve fibre (density, branch density, length and tortuosity) at baseline and after 24 months from first visit. This was not planned as an intervention trial and was simply an observational follow-up. RESULTS: At baseline, nerve fibre density (18.8 ± 2.1 vs. 46.0 ± 3.8 number/mm(2), P = 0.001), nerve branch density (6.9 ± 1.5 vs. 35.6 ± 6.7 number/mm(2), P < 0.0001), nerve fibre length (8.3 ± 0.9 vs. 13.5 ± 0.8 mm/mm(2), P < 0.0001) and nerve fibre tortuosity (19.8 ± 1.6 vs. 22.7 ± 2.2, P < 0.05) were significantly lower in patients with diabetes than in control subjects. At follow-up, glycaemic control (HbA(1c) 64 ± 3 to 58 ± 2 mmol/mol, P = 0.08), total cholesterol (4.9 ± 0.2 to 4.2 ± 0.2 mmol/l, P = 0.01), systolic blood pressure (145.8 ± 4.9 to 135.9 ± 3.7 mmHg, P = 0.09) and diastolic blood pressure (77.8 ± 2.7 to 70.8 ± 2.5, P = 0.03) improved. Nerve fibre density (24.1 ± 2.0, P = 0.05), nerve branch density (11.1 ± 1.3, P < 0.01) and nerve fibre tortuosity (22.6 ± 1.5, P = 0.05) increased significantly, with no change in nerve fibre length (8.4 ± 0.5). Improvement in nerve fibre density correlated significantly with the improvement in HbA(1c) (r = -0.51, P = 0.008). Via four multifactorial regressions, this confirms the negative association between HbA(1c) and nerve fibre density (P = 0.02). CONCLUSIONS: This study shows that corneal confocal microscopy may be employed in longitudinal studies to assess progression of human diabetic neuropathy and also supports the hypothesis that improvements in risk factors for diabetic neuropathy, in particular HbA(1c) , may lead to morphological repair of nerve fibres.


Assuntos
Córnea/patologia , Diabetes Mellitus Tipo 1/patologia , Diabetes Mellitus Tipo 2/patologia , Neuropatias Diabéticas/patologia , Microscopia Confocal , Fibras Nervosas/patologia , Córnea/inervação , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/complicações , Neuropatias Diabéticas/sangue , Feminino , Hemoglobinas Glicadas/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
19.
Cont Lens Anterior Eye ; 34(1): 7-11, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20851037

RESUMO

AIM/HYPOTHESIS: Immune mechanisms have been proposed to play a role in the development of diabetic neuropathy. We employed in vivo corneal confocal microscopy (CCM) to quantify the presence and density of Langerhans cells (LCs) in relation to the extent of corneal nerve damage in Bowman's layer of the cornea in diabetic patients. METHODS: 128 diabetic patients aged 58 ± 1 yrs with a differing severity of neuropathy based on Neuropathy Deficit Score (NDS-4.7 ± 0.28) and 26 control subjects aged 53 ± 3 yrs were examined. Subjects underwent a full neurological evaluation, evaluation of corneal sensation with non-contact corneal aesthesiometry (NCCA) and corneal nerve morphology using corneal confocal microscopy (CCM). RESULTS: The proportion of individuals with LCs was significantly increased in diabetic patients (73.8%) compared to control subjects (46.1%), P = 0.001. Furthermore, LC density (no/mm(2)) was significantly increased in diabetic patients (17.73 ± 1.45) compared to control subjects (6.94 ± 1.58), P = 0.001 and there was a significant correlation with age (r = 0.162, P = 0.047) and severity of neuropathy (r = -0.202, P = 0.02). There was a progressive decrease in corneal sensation with increasing severity of neuropathy assessed using NDS in the diabetic patients (r = 0.414, P = 0.000). Corneal nerve fibre density (P < 0.001), branch density (P < 0.001) and length (P < 0.001) were significantly decreased whilst tortuosity (P < 0.01) was increased in diabetic patients with increasing severity of diabetic neuropathy. CONCLUSION: Utilising in vivo corneal confocal microscopy we have demonstrated increased LCs in diabetic patients particularly in the earlier phases of corneal nerve damage suggestive of an immune mediated contribution to corneal nerve damage in diabetes.


Assuntos
Córnea/imunologia , Córnea/inervação , Neuropatias Diabéticas/imunologia , Neuropatias Diabéticas/patologia , Células de Langerhans/imunologia , Células de Langerhans/patologia , Contagem de Células , Córnea/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
20.
Artigo em Inglês | MEDLINE | ID: mdl-20879244

RESUMO

Corneal Confocal Microscopy (CCM) imaging is a non-invasive surrogate of detecting, quantifying and monitoring diabetic peripheral neuropathy. This paper presents an automated method for detecting nerve-fibres from CCM images using a dual-model detection algorithm and compares the performance to well-established texture and feature detection methods. The algorithm comprises two separate models, one for the background and another for the foreground (nerve-fibres), which work interactively. Our evaluation shows significant improvement (p approximately 0) in both error rate and signal-to-noise ratio of this model over the competitor methods. The automatic method is also evaluated in comparison with manual ground truth analysis in assessing diabetic neuropathy on the basis of nerve-fibre length, and shows a strong correlation (r = 0.92). Both analyses significantly separate diabetic patients from control subjects (p approximately 0).


Assuntos
Algoritmos , Córnea/inervação , Córnea/patologia , Retinopatia Diabética/patologia , Interpretação de Imagem Assistida por Computador/métodos , Microscopia Confocal/métodos , Fibras Nervosas/patologia , Oftalmoscopia/métodos , Reconhecimento Automatizado de Padrão/métodos , Inteligência Artificial , Humanos , Aumento da Imagem/métodos , Modelos Biológicos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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