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1.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-20096073

RESUMO

Artificial intelligence can potentially provide a substantial role in streamlining chest computed tomography (CT) diagnosis of COVID-19 patients. However, several critical hurdles have impeded the development of robust AI model, which include deficiency, isolation, and heterogeneity of CT data generated from diverse institutions. These bring about lack of generalization of AI model and therefore prevent it from applications in clinical practices. To overcome this, we proposed a federated learning-based Unified CT-COVID AI Diagnostic Initiative (UCADI, http://www.ai-ct-covid.team/), a decentralized architecture where the AI model is distributed to and executed at each host institution with the data sources or client ends for training and inferencing without sharing individual patient data. Specifically, we firstly developed an initial AI CT model based on data collected from three Tongji hospitals in Wuhan. After model evaluation, we found that the initial model can identify COVID from Tongji CT test data at near radiologist-level (97.5% sensitivity) but performed worse when it was tested on COVID cases from Wuhan Union Hospital (72% sensitivity), indicating a lack of model generalization. Next, we used the publicly available UCADI framework to build a federated model which integrated COVID CT cases from the Tongji hospitals and Wuhan Union hospital (WU) without transferring the WU data. The federated model not only performed similarly on Tongji test data but improved the detection sensitivity (98%) on WU test cases. The UCADI framework will allow participants worldwide to use and contribute to the model, to deliver a real-world, globally built and validated clinic CT-COVID AI tool. This effort directly supports the United Nations Sustainable Development Goals number 3, Good Health and Well-Being, and allows sharing and transferring of knowledge to fight this devastating disease around the world.

2.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-20037325

RESUMO

Background and purposeThe worldwide pandemic of coronavirus disease 2019 (COVID-19) greatly challenges public medical systems. With limited medical resources, the treatment priority is determined by the severity of patients. However, many mild outpatients quickly deteriorate into severe/critical stage. It is crucial to early identify them and give timely treatment for optimizing treatment strategy and reducing mortality. This study aims to establish an AI model to predict mild patients with potential malignant progression. MethodsA total of 133 consecutively mild COVID-19 patients at admission who was hospitalized in Wuhan Pulmonary Hospital from January 3 to February 13, 2020, were selected in this retrospective IRB-approved study. All mild patients were categorized into groups with or without malignant progression. The clinical and laboratory data at admission, the first CT, and the follow-up CT at the severe/critical stage of the two groups were compared. Both multivariate logistic regression and deep learning-based methods were used to build the prediction models, with their area under ROC curves (AUC) compared. ResultsMultivariate logistic regression depicted 6 risk factors for malignant progression: age >55years (OR 5.334, 95%CI 1.8-15.803), comorbid with hypertension (OR 5.093, 95%CI 1.236-20.986), a decrease of albumin (OR 4.01, 95%CI 1.216-13.223), a decrease of lymphocyte (OR 3.459, 95%CI 1.067-11.209), the progressive consolidation from CT1 to CTsevere (OR 1.235, 95%CI 1.018-1.498), and elevated HCRP (OR 1.015, 95%CI 1.002-1.029); and one protective factor: the presence of fibrosis at CT1 (OR 0.656, 95%CI 0.473-0.91). By combining the clinical data and the temporal information of the CT data, our deep learning-based models achieved the best AUC of 0.954, which outperformed logistic regression (AUC: 0.893), ConclusionsOur deep learning-based methods can identify the mild patients who are easy to deteriorate into severe/critical cases efficiently and accurately, which undoubtedly helps to optimize the treatment strategy, reduce mortality, and relieve the medical pressure.

3.
The Journal of Practical Medicine ; (24): 3348-3353, 2017.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-661399

RESUMO

Objective To investigate the effect of microRNA-497 (miR-497) on cell proliferation and apoptosis capability of baldder cancer cell line EJ. Methods EJ human baldder cancer cells were divided into miR-497 mimics group,mimics NC group,miR-497 inhibitor group and inhibitor NC group. MiR-497 mimics,mimics NC,miR-497 inhibitor and inhibitor NC were transfected into EJ cells by LipfectamineTM 2000. The transfection effi-ciency was observed under a fluorescence microscope 6 hours after. And qRT-PCR was used to detected the expres-sion of miR-49748 hours after. Plate clone formation assay ,MTT assay and flow-cytometric analysis of apoptosis were used to detect the cell proliferation and apoptosis of bladder cancer EJ cells. Western blot was employed to de-termine the protein expressions of bcl-2 and caspase-3. Results Under fluorescence microscope ,the efficiency rate of four groups were over 90%. And qRT-PCR results showed miR-497 expression in EJ cells increased signifi-cantly in miR-497 mimics group than those in the control group(P<0.01),while miR-497 inhibitor post expres-sion decreased(P<0.01). Overexpression of miR-497 significantly suppressed EJ cells proliferation(P<0.01), and prompted EJ cells apoptosis(P < 0.01)compared with the control group. Moreover ,opposite results were ob-tained when miR-497 inhibitor was transfected into EJ cells . Compared with negative control ,the protein expres-sion of Bcl-2 down-regulated(P < 0.01)and Caspase-3 up-regulated(P < 0.01)in miR-497 mimics transfection group. Conclusions MiR-497 could suppress the proliferation and promote apoptosis of EJ cells ,which might be related to the protein expression of Bcl-2 and Caspase-3.

4.
The Journal of Practical Medicine ; (24): 3348-3353, 2017.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-658480

RESUMO

Objective To investigate the effect of microRNA-497 (miR-497) on cell proliferation and apoptosis capability of baldder cancer cell line EJ. Methods EJ human baldder cancer cells were divided into miR-497 mimics group,mimics NC group,miR-497 inhibitor group and inhibitor NC group. MiR-497 mimics,mimics NC,miR-497 inhibitor and inhibitor NC were transfected into EJ cells by LipfectamineTM 2000. The transfection effi-ciency was observed under a fluorescence microscope 6 hours after. And qRT-PCR was used to detected the expres-sion of miR-49748 hours after. Plate clone formation assay ,MTT assay and flow-cytometric analysis of apoptosis were used to detect the cell proliferation and apoptosis of bladder cancer EJ cells. Western blot was employed to de-termine the protein expressions of bcl-2 and caspase-3. Results Under fluorescence microscope ,the efficiency rate of four groups were over 90%. And qRT-PCR results showed miR-497 expression in EJ cells increased signifi-cantly in miR-497 mimics group than those in the control group(P<0.01),while miR-497 inhibitor post expres-sion decreased(P<0.01). Overexpression of miR-497 significantly suppressed EJ cells proliferation(P<0.01), and prompted EJ cells apoptosis(P < 0.01)compared with the control group. Moreover ,opposite results were ob-tained when miR-497 inhibitor was transfected into EJ cells . Compared with negative control ,the protein expres-sion of Bcl-2 down-regulated(P < 0.01)and Caspase-3 up-regulated(P < 0.01)in miR-497 mimics transfection group. Conclusions MiR-497 could suppress the proliferation and promote apoptosis of EJ cells ,which might be related to the protein expression of Bcl-2 and Caspase-3.

5.
Chinese Journal of Urology ; (12): 127-131, 2012.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-420787

RESUMO

Objective To analyze the effect of antibiotic treatment on prostate specific antigen (PSA) derivations in patients with and without prostate cancer and to further determine if the changes of PSA values after antibiotic treatment could help to exclude inflammation in the differential diagnosis of an abnormal PSA.MethodsA total of 100 patients with lower urinary tract symptoms,a PSA level of 4 to 10 μg/L,free PSA/total PSA (fPSA/tPSA) ratio < 0.25,and a negative digital rectal examination and transrectal ultrasonography were enrolled in this study.All patients received 500 mg of ciprofloxacin twice a day for 3 weeks.Free and total PSA values were measured before and after antibiotic treatment.All the patients were then scheduled for 12-core prostate biopsy.Results The mean tPSA value was (6.5 ± 1.2) and (5.1 ± 1.2) μg/L respectively before and after antibiotic treatment ( P < 0.01 ).Ninety-one patients (91.0%) showed tPSA reduction after antibiotic therapy,of which 13 ( 14.3% ) had prostate cancer on biopsy.In 17 cases (18.7%) post-treatment tPSA was less than 4 μg/L.Three of the 17 cases (17.6%)had prostate cancer on biopsy.In 6 of the 100 men post-treatment tPSA was between 4 and 10 μg/L and the fPSA/tPSA ratio was above 0.25.One of these cases had prostate cancer on biopsy.Seven cases had a >50% reduction in PSA levels with no positive biopsy results.Although mean total PSA and PSAD decreased after treatment in both groups,the reductions within these parameters were not significantly different between patients with and without prostate cancer (P > 0.05).Furthermore,no differences emerged in terms of the changes of other PSA derivations including fPSA and fPSA/tPSA ( P > 0.05 ).ConclusionsThe PSA levels may change with long-term antibiotic treatment in patients with elevated PSA values.A decrease in PSA after antibiotic treatment does not rule out the presence of prostate cancer even if PSA decreases to a normal level.But a > 50% reduction in PSA levels may be associated with a decreasing risk of prostate cancer,which may allow a postponement of prostate biopsy in selected patients.

6.
Chinese Journal of Urology ; (12): 697-699, 2009.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-392749

RESUMO

Objective To determine whether an increased number of transrectal biopsy cores improves the accuracy of biopsy Gleason score. Methods This study reviewed a total of 86 patients who were diagnosed as prostate cancer by transrectal needle biopsy and subsequently underwent radical prostatectomy (RP) without neoadjuvant therapy.The rate of grading concordance between biopsy and RP specimens was analyzed by dividing these patients into 2 groups according to the biopsy cores:group A,46 patients who underwent transrectai biopsy sampling of 6 cores,and group B,40 patients who underwent biopsy sampling of 13 cores. Results The concordance between prostate biopsy and radical prostatectomy Gleason score was 65.0%and 34.8% for 13 core and 6 core biopsy,respectirely (P<0.05).Furthermore,these findings tended to be more prominent as the biopsy Gleason score was lower.Multivariate analysis identified the number of biopsy cores and percent of positive biopsy cores as independent predictors of accurate Gleason grading regardless of other parameters examined in this study. Conclusion Extended needle biopsy may increases the accuracy of biopsy Gleason score for assessing final prostate cancer grade.

7.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-591188

RESUMO

AIM: Site-specific functional neurons of brains were with different cellular morphology. It has not been fully understood whether the grafted neural stem cells could differentiate into the site-specific neurons. This experiment is to investigate the neuronal differentiation of the neural stem cells derived from a human fetal brain after transplanted into young rats' brains, to study the possibility of cell-replacement therapy for children's brain disorders with neural stem cells. METHODS: Experiments were performed at the Cell Laboratory of Naval General Hospital from April to July 2007. ①Human fetal brain tissues of 16 week gestation were provided by Department of Gynaecology and Obstetrics of Naval Hospital. Pregnant woman and family members signed an informed consent. Experimental intervention was approved by Hospital Ethical Committee. Fourteen clean brood young SD rats aged 10 days, irrespective of gender, were provided by Experimental Animal Center of Medical College of Peking University. Animal intervention met the animal ethical standards. ②The neural stem cell spheres were derived from the fetal brain tissues of 16 week gestation. The differentiation multipotency of the neurosphere was identified when cultured in a child's cerebrospinal fluid (CSF). The neurospheres cultured in vitro for 14 days were injected into the lateral ventricles of young rats of 10 days old. The rats were respectively killed at days 4, 7 and 14 after transplantation. The special immuno-fluorescent assays were performed using anti-human neurofilament (anti-hNF) to show the location and morphology of graft neurons. RESULTS: ①The typical floating neurospheres were obtained, with the potency to differentiate into neurons, astrocytes and oligodendrocytes. ②The neuronal differentiation of grafts was detected with the mixture of three monoclonal antibodies against human neurofilament. Four days after transplantation, the immune response positive cells lied within the granule cell layer of cerebral cortex were shown in the shape of granule cells, or within the pyramid cell layer in the shape of pyramid cells with long processes, and the interneuron-like cells also were seen. The Purkinje cells arranging in a monolayer were detected in the cerebellum. Compared the results at different time points, the location of grafts were the same. The graft cells were less and the processes were longer over time. CONCLUSION: The in vitro cultured neurosphere cells can migrate into brain tissues and differentiate into site-specific neurons in shape after transplanting into the lateral ventricles of young rats. It is suggested that the host brain tissue microenvironment played an important role in guiding the graft differentiation into neurons. The results have an important significance for understanding cell replacement of developing brain disorders.

8.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-575829

RESUMO

Objective A morphometric study was carried out on GABAergic neurons and astrocytes in primary auditory cortex of 4 young cats (1-3 years old, 20-2.5 kg) and 4 old cats (10-13-year-old, 3-3.5 kg), in order to explore the age-related changes and the probably physical effects underlying these changes. Methods The same regions of the primary auditory cortex (AI) were comparatively studied. Nissl staining and immunohistochemical methods were applied to explore the differences of GABAergic neurons and astrocytes(specifically labeled by GFAP as a mark as antibody) in the primary auditory cortex(Al) between young and old cats. Serial cross-sections from two age groups were stained with Nissl for layer structure observation and demonstration of neurons; Adjacent sections were stained with anti_GABA immunohistochemistry for localizing and characterizing GABAergic and with anti-GFAP for astrocytes in AI. Results The diameter, density and number of GABAergic neurons in Al of old cats declined significantly compared with the counterpart in young cats, especially in layers Ⅱ,Ⅲ of AI; but the change in GFAP-IR cells was reversed: old cats showed clearly larger number and stronger staining of GFAP-IR cells than that in young cats. The GFAP-IR cell bodies and dendrites swelled obviously in old cats, especially in layer Ⅰ of AI and in white matter. Conclusion The result presented a direct morphological evidence for weakness of GABAergic intracortical inhibition, which is considered to be a possible mechanism for age-related acoustic function decline. The enhanced function of astrocytes may play an important role in decreasing the GABA content in AI of the old individuals.

9.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-581184

RESUMO

Objective To investigate the relationship between the secondary hypertension and pituitary microadenoma,and to explore the diagnostic value of magnetic resonance imaging(MRI) examination for pituitary microadenoma.Methods We analyzed the clinical information,laboratory examination results and imaging data in 21 hypertension patients complicated with pituitary microadenoma.Results The manifestations of the 21 patients were as follows:(1) The onset of hypertension was in young age,complicated with headache;(2) The results of 24-hour ambulatory blood pressure monitor(24h ABPM) showed the disappearance of circadian rhythm of blood pressure,and obvious increase of systolic/diastolic blood pressure;(3) The antihypertensive effect of antihypertensive drugs was not satisfactory;(4) Of adenohypophyseal hormones,adrenocorticotrophic hormone(ACTH) level in most patients and prolactin(PRL) level in a few patients were higher than the normal level,and the other hormones levels were normal;(5) The results of MRI examination presented adrenal cortical hyperplasia,adrenal adenoma and chromaffin tumor in some patients.(6) The results of MRI examination showed pituitary microadenoma in all of the patients.Conclusion For those middle-aged and young hypertension patients on whom antihypertensive effect of drugs is poor,MRI examination for adrenal gland and pituitary gland should be taken as the routine examination.MRI examination is the optimal imaging method for pituitary microadenoma,and supply evidence for the syndrome differentiation and treatment of pituitary microadenoma.

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