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1.
J Endocrinol Invest ; 46(10): 2147-2155, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36952215

RESUMO

PURPOSE: In mice, adipose tissue-derived stem cells (ASCs) reach the systemic circulation and establish ectopic adipose depots fostering insulin resistance, but whether this occurs in humans is unknown. We examined circulating ASCs in individuals with various combination of metabolic syndrome traits. METHODS: We enrolled patients attending a routine metabolic evaluation or scheduled for bariatric surgery. We quantified ASCs as CD34+CD45-CD31-(CD36+) cells in the stromal vascular fraction of subcutaneous and visceral adipose tissue samples and examined the presence and frequency of putative ASCs in peripheral blood. RESULTS: We included 111 patients (mean age 59 years, 55% males), 40 of whom were scheduled for bariatric surgery. The population of CD34+CD45-CD31- ASCs was significantly more frequent in visceral than subcutaneous adipose depots (10.4 vs 4.1% of the stromal vascular fraction; p < 0.001), but not correlated with BMI or metabolic syndrome traits. The same phenotype of ASCs was detectable in peripheral blood of 58.6% of patients. Those with detectable circulating ASCs had significantly higher BMI (37.8 vs 33.3 kg/m2; p = 0.003) and waist (111.2 vs 105.4 cm; p = 0.001), but no difference in other metabolic syndrome traits (p = 0.84). After bariatric surgery, patients with detectable circulating ASCs had greater BMI reductions at 6 months (- 10.4 vs - 7.8 kg/m2; p = 0.014). CONCLUSION: Presence of putative circulating ASCs, antigenically similar to those observed in the adipose tissue, is associated with greater adiposity and larger BMI reduction after surgery, but not with clinical signs of metabolic impairment. The role of circulating ASCs in adipose tissue biology and systemic metabolism deserves further investigation.


Assuntos
Cirurgia Bariátrica , Síndrome Metabólica , Masculino , Humanos , Camundongos , Animais , Pessoa de Meia-Idade , Feminino , Síndrome Metabólica/metabolismo , Obesidade/metabolismo , Tecido Adiposo/metabolismo , Células-Tronco/metabolismo
2.
AJNR Am J Neuroradiol ; 44(1): 11-16, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36521960

RESUMO

BACKGROUND AND PURPOSE: Protocolling, the process of determining the most appropriate acquisition parameters for an imaging study, is time-consuming and produces variable results depending on the performing physician. The purpose of this study was to assess the potential of an artificial intelligence-based semiautomated tool in reducing the workload and decreasing unwarranted variation in the protocolling process. MATERIALS AND METHODS: We collected 19,721 MR imaging brain examinations at a large academic medical center. Criterion standard labels were created using physician consensus. A model based on the Long Short-Term Memory network was trained to predict the most appropriate protocol for any imaging request. The model was modified into a clinical decision support tool in which high-confidence predictions, determined by the values the model assigns to each possible choice, produced the best protocol automatically and low confidence predictions provided a shortened list of protocol choices for review. RESULTS: The model achieved 90.5% accuracy in predicting the criterion standard labels and demonstrated higher agreement than the original protocol assignments, which achieved 85.9% accuracy (κ = 0.84 versus 0.72, P value < .001). As a clinical decision support tool, the model automatically assigned 70% of protocols with 97.3% accuracy and, for the remaining 30% of examinations, achieved 94.7% accuracy when providing the top 2 protocols. CONCLUSIONS: Our model achieved high accuracy on a standard based on physician consensus. It showed promise as a clinical decision support tool to reduce the workload by automating the protocolling of a sizeable portion of examinations while maintaining high accuracy for the remaining examinations.


Assuntos
Inteligência Artificial , Sistemas de Apoio a Decisões Clínicas , Humanos , Imageamento por Ressonância Magnética/métodos , Neuroimagem , Encéfalo/diagnóstico por imagem
3.
Clin Radiol ; 75(3): 237.e1-237.e9, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31787211

RESUMO

AIM: To investigate the feasibility of applying a deep convolutional neural network (CNN) for detection/localisation of acute proximal femoral fractures (APFFs) on hip radiographs. MATERIALS AND METHODS: This study had institutional review board approval. Radiographs of 307 patients with APFFs and 310 normal patients were identified. A split ratio of 3/1/1 was used to create training, validation, and test datasets. To test the validity of the proposed model, a 20-fold cross-validation was performed. The anonymised images from the test cohort were shown to two groups of radiologists: musculoskeletal radiologists and diagnostic radiology residents. Each reader was asked to assess if there was a fracture and localise it if one was detected. The area under the receiver operator characteristics curve (AUC), sensitivity, and specificity were calculated for the CNN and readers. RESULTS: The mean AUC was 0.9944 with a standard deviation of 0.0036. Mean sensitivity and specificity for fracture detection was 97.1% (81.5/84) and 96.7% (118/122), respectively. There was good concordance with saliency maps for lesion identification, but sensitivity was lower for characterising location (subcapital/transcervical, 84.1%; basicervical/intertrochanteric, 77%; subtrochanteric, 20%). Musculoskeletal radiologists showed a sensitivity and specificity for fracture detection of 100% and 100% respectively, while residents showed 100% and 96.8%, respectively. For fracture localisation, the performance decreased slightly for human readers. CONCLUSION: The proposed CNN algorithm showed high accuracy for detection of APFFs, but the performance was lower for fracture localisation. Overall performance of the CNN was lower than that of radiologists, especially in localizing fracture location.


Assuntos
Inteligência Artificial , Fraturas do Quadril/diagnóstico por imagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudo de Prova de Conceito , Estudos Retrospectivos , Sensibilidade e Especificidade
4.
Br J Neurosurg ; 33(2): 119-124, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30784332

RESUMO

Purpose of the article: To determine whether intraoperative ventilation with pure oxygen during the last stage of surgery reduces the occurrence and volume of postoperative pneumocephalus when compared to conventional air/oxygen mixture in patients undergoing craniotomy. MATERIAL AND METHODS: prospective randomized single-blinded study to compare the rate of occurrence and volume of postoperative pneumocephalus in patients undergoing craniotomy receiving intraoperative ventilation with pure oxygen (Group B) versus a conventional air/oxygen 1:1 mixture (Group A) during the last stage of surgery. This trial was registered in ClinicalTrials.gov #NCT02722928, protocol number 2015H0032. RESULTS: One hundred patients were randomized into group 'A' and group 'B'. Seventy patients were included in the final analysis with 39 patients allocated in group 'A' and 31 patients in group 'B'. Median and IQR were used for postoperative penumocephalus volume. Group A: 9.65 [3.61-23.20]; Group B: 7.06 [2.70-20.1]. Our study showed no prophylactic effect on postoperative pneumocephalus volume when using mechanical ventilation with higher oxygen concentrations than the standard FiO2 during the last stage of surgery in patients undergoing craniotomy (p = .47). No statistical difference was found in SICU LOS between groups (median 1,380 min [group A] versus 1,524 min [group B]; p = .18). CONCLUSION: The use of intraoperative mechanical ventilation with pure oxygen was not associated with a prophylactic effect on the occurrence and extent of postoperative pneumocephalus in our patient setting. Published literature describing the extent of postoperative pneumocephalus is limited or highly variable among institutions.


Assuntos
Craniotomia , Oxigenoterapia/métodos , Pneumocefalia/epidemiologia , Pneumocefalia/etiologia , Complicações Pós-Operatórias/epidemiologia , Respiração Artificial/métodos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultados Negativos , Procedimentos Neurocirúrgicos/métodos , Pneumocefalia/prevenção & controle , Complicações Pós-Operatórias/prevenção & controle , Estudos Prospectivos , Método Simples-Cego
5.
Obes Surg ; 29(1): 292-296, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30251088

RESUMO

BACKGROUND: Pre-operative diet may play an important role as far as patients' fitness for surgery, post-operative outcomes, and successful weight loss. Our aim was to compare surgical outcome and weight loss in two groups of patients who were offered two different pre-operative kinds of diet: very low calorie diet (VLCD) and very low calorie ketogenic diet (VLCKD). METHODS: Patients candidate for bariatric surgery (laparoscopic sleeve gastrectomy) were registered and assessed according to pre- and post-diet BMI, operative time, hospital stay, drainage output, and hemoglobin (Hb) levels. Patients' preference influenced the type of diet. RESULTS: From January to December 2016, 178 patients (139 F and 39 M) were enrolled in this study. The mean age was 43 years. In total, 72 patients were on VLCKD while 106 patients on VLCD. Pre-diet mean BMI was 46.3 ± 6.3 kg/m2 for VLCKD group and 43.1 ± 6.9 kg/m2 for VLCD group, while immediately pre-op BMI were 43.9 ± 5.9 kg/m2 and 41.9 ± 6.8 kg/m2, respectively. Drainage output and hemoglobin levels after surgery resulted significantly correlated with diet induced BMI reduction (141.2 ± 75.8 vs. 190.7 ± 183.6 ml, p = 0.032; 13.1 ± 1.2 vs. 12.7 ± 1.5 g/l, p = 0.04). The percentage of patients requiring a hospital stay longer than anticipated (> 3 days) was 2.8% in the VLCKD group and 10.4% in the VLCD group (p = 0.048). CONCLUSIONS: In our experience, VLCKD showed better results than VLCD on surgical outcome, influencing drainage output, post-operative hemoglobin levels, and hospital stay.


Assuntos
Restrição Calórica/métodos , Dieta Cetogênica/métodos , Obesidade Mórbida/dietoterapia , Obesidade Mórbida/cirurgia , Adulto , Cirurgia Bariátrica , Terapia Combinada , Feminino , Gastrectomia , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Período Pré-Operatório , Resultado do Tratamento , Redução de Peso
6.
Dis Markers ; 34(4): 269-78, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23396294

RESUMO

BACKGROUND: Obesity is currently epidemic in many countries worldwide and is strongly related to diabetes and cardiovascular disease. Mass spectrometry, in particular matrix-assisted laser desorption/ionization time of flight (MALDI-TOF) is currently used for detecting different pattern of expressed protein. This study investigated the differences in low molecular weight (LMW) peptide profiles between obese and normal-weight subjects in combination with multivariate statistical analysis. MATERIALS: Serum samples of 60 obese patients and 10 healthy subjects were treated by cut-off membrane (30000 Da) to remove the most abundant proteins. The filtrates containing the LMW protein/peptides were analyzed by MALDI-TOF mass spectrometry. Dataset was elaborated to align and normalize the spectra. We performed cluster analysis and principal component analysis to detect some ionic species that could characterize and classify the subject groups. RESULTS: We observed a down-expression of ionic species at m/z 655.94 and an over-expression of species at m/z 1518.78, 1536.77, 1537.78 and 1537.81 in obese patients. Furthermore we found some ionic species that can distinguish obese patients with diabetes from those with normal glucose level. CONCLUSION: Serum peptide profile of LMW associate with multivariate statistical approach was revealed as a promising tool to discriminate and characterize obese patients and it was able to stratify them in relation to comorbidity that usually are associated with this disease. Further research involving a larger sample will be required to validate these findings.


Assuntos
Obesidade Mórbida/sangue , Peptídeos/sangue , Estudos de Casos e Controles , Humanos , Análise Multivariada , Software , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
7.
Environ Pollut ; 142(2): 274-87, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16343716

RESUMO

The analysis of 90 surficial sediments from three docks of the Naples Harbour (Levante, Granili, and Diaz) permits to compare the distribution modes of heavy metals with grain sizes, total organic carbon content (TOC) and distribution patterns of benthic foraminifera. Foraminiferal density and species richness decrease with the increasing toxic elements concentrations from the Levante to the Diaz dock. Median concentrations of Ni, Pb, Zn, and Hg (medians of 21.43 mg/kg, 270.24 mg/kg, 489.65 mg/kg, and 1.18 mg/kg, respectively) were reported for the Diaz dock where foraminifera are absent, thus suggesting a possible impact of toxic elements on the benthic ecosystem balance. Compared to the unpolluted marine sediments of the Granili dock, the Levante area shows higher heavy metals levels and a quasi-oligotypic benthic assemblage. This is dominated by the tolerant species Ammonia tepida that may be used as bio-indicator of pollution of anthropised marine sediments.


Assuntos
Monitoramento Ambiental/métodos , Eucariotos , Sedimentos Geológicos/química , Metais Pesados/toxicidade , Navios , Poluentes Químicos da Água/toxicidade , Animais , Eucariotos/efeitos dos fármacos , Resíduos Industriais , Itália , Chumbo/análise , Chumbo/toxicidade , Mercúrio/análise , Mercúrio/toxicidade , Níquel/análise , Níquel/toxicidade , Tamanho da Partícula , Água do Mar , Zinco/análise , Zinco/toxicidade , Zooplâncton
8.
Arq Neuropsiquiatr ; 59(2-B): 411-6, 2001 Jun.
Artigo em Português | MEDLINE | ID: mdl-11460189

RESUMO

The lesions of the central nervous system represent an important cause of morbid-mortality in the neonatal period. This is due to the vulnerability of the brain to several adverse conditions during gestation and after birth. This study analyses the prevalence and pattern of central nervous system lesions in neonates autopsied at Hospital de Clínicas - Curitiba. There were 5743 pediatric autopsies performed in the Sector of Anatomic Pathology from 1960 to 1995 with 2049 cases corresponding to death during neonatal period. These later autopsies were reviewed and all cases with central nervous system lesions were selected and classified according to sex, age and pattern of central nervous system lesion. The central nervous system was affected in 1616 (78,87%) of neonatal autopsies and there was predominance of intracerebral hemorrhages (73,39%), congenital malformations (4,27%) and infections (3,59%). The hypoxic hemorrhages are the most prevalent central nervous system lesions in the neonatal period, affecting mainly premature babies. There was predominance of central nervous system malformations in the female neonates.


Assuntos
Doenças do Sistema Nervoso Central/epidemiologia , Distribuição por Idade , Autopsia , Doenças do Sistema Nervoso Central/congênito , Doenças do Sistema Nervoso Central/patologia , Infecções do Sistema Nervoso Central/epidemiologia , Infecções do Sistema Nervoso Central/patologia , Feminino , Humanos , Recém-Nascido , Hemorragias Intracranianas/epidemiologia , Hemorragias Intracranianas/patologia , Masculino , Prevalência , Estudos Retrospectivos , Distribuição por Sexo
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