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1.
Diagnostics (Basel) ; 14(13)2024 Jul 05.
Article in English | MEDLINE | ID: mdl-39001331

ABSTRACT

Artificial Intelligence (AI)-based image analysis has immense potential to support diagnostic histopathology, including cancer diagnostics. However, developing supervised AI methods requires large-scale annotated datasets. A potentially powerful solution is to augment training data with synthetic data. Latent diffusion models, which can generate high-quality, diverse synthetic images, are promising. However, the most common implementations rely on detailed textual descriptions, which are not generally available in this domain. This work proposes a method that constructs structured textual prompts from automatically extracted image features. We experiment with the PCam dataset, composed of tissue patches only loosely annotated as healthy or cancerous. We show that including image-derived features in the prompt, as opposed to only healthy and cancerous labels, improves the Fréchet Inception Distance (FID) by 88.6. We also show that pathologists find it challenging to detect synthetic images, with a median sensitivity/specificity of 0.55/0.55. Finally, we show that synthetic data effectively train AI models.

2.
Int J Mol Sci ; 24(17)2023 Aug 25.
Article in English | MEDLINE | ID: mdl-37686032

ABSTRACT

Chronic kidney disease (CKD) progression is associated with persisting oxidative stress, which impairs the NO-sGC-cGMP signaling cascade through the formation of oxidized and heme-free apo-sGC that cannot be activated by NO. Runcaciguat (BAY 1101042) is a novel, potent, and selective sGC activator that binds and activates oxidized and heme-free sGC and thereby restores NO-sGC-cGMP signaling under oxidative stress. Therefore, runcaciguat might represent a very effective treatment option for CKD/DKD. The potential kidney-protective effects of runcaciguat were investigated in ZSF1 rats as a model of CKD/DKD, characterized by hypertension, hyperglycemia, obesity, and insulin resistance. ZSF1 rats were treated daily orally for up to 12 weeks with runcaciguat (1, 3, 10 mg/kg/bid) or placebo. The study endpoints were proteinuria, kidney histopathology, plasma, urinary biomarkers of kidney damage, and gene expression profiling to gain information about relevant pathways affected by runcaciguat. Furthermore, oxidative stress was compared in the ZSF1 rat kidney with kidney samples from DKD patients. Within the duration of the 12-week treatment study, kidney function was significantly decreased in obese ZSF1 rats, indicated by a 20-fold increase in proteinuria, compared to lean ZSF1 rats. Runcaciguat dose-dependently and significantly attenuated the development of proteinuria in ZSF1 rats with reduced uPCR at the end of the study by -19%, -54%, and -70% at 1, 3, and 10 mg/kg/bid, respectively, compared to placebo treatment. Additionally, average blood glucose levels measured as HbA1C, triglycerides, and cholesterol were increased by five times, twenty times, and four times, respectively, in obese ZSF1 compared to lean rats. In obese ZSF1 rats, runcaciguat reduced HbA1c levels by -8%, -34%, and -76%, triglycerides by -42%, -55%, and -71%, and cholesterol by -16%, -17%, and -34%, at 1, 3, and 10 mg/kg/bid, respectively, compared to placebo. Concomitantly, runcaciguat also reduced kidney weights, morphological kidney damage, and urinary and plasma biomarkers of kidney damage. Beneficial effects were accompanied by changes in gene expression that indicate reduced fibrosis and inflammation and suggest improved endothelial stabilization. In summary, the sGC activator runcaciguat significantly prevented a decline in kidney function in a DKD rat model that mimics common comorbidities and conditions of oxidative stress of CKD patients. Thus, runcaciguat represents a promising treatment option for CKD patients, which is in line with recent phase 2 clinical study data, where runcaciguat showed promising efficacy in CKD patients (NCT04507061).


Subject(s)
Kidney , Renal Insufficiency, Chronic , Animals , Rats , Cyclic GMP , Glycated Hemoglobin , Heme , Obesity , Proteinuria , Renal Insufficiency, Chronic/drug therapy , Clinical Trials, Phase II as Topic
3.
Cell Rep Med ; 4(4): 100992, 2023 04 18.
Article in English | MEDLINE | ID: mdl-37023747

ABSTRACT

Diabetic kidney disease (DKD) is the most common cause of renal failure. Therapeutics development is hampered by our incomplete understanding of animal models on a cellular level. We show that ZSF1 rats recapitulate human DKD on a phenotypic and transcriptomic level. Tensor decomposition prioritizes proximal tubule (PT) and stroma as phenotype-relevant cell types exhibiting a continuous lineage relationship. As DKD features endothelial dysfunction, oxidative stress, and nitric oxide depletion, soluble guanylate cyclase (sGC) is a promising DKD drug target. sGC expression is specifically enriched in PT and stroma. In ZSF1 rats, pharmacological sGC activation confers considerable benefits over stimulation and is mechanistically related to improved oxidative stress regulation, resulting in enhanced downstream cGMP effects. Finally, we define sGC gene co-expression modules, which allow stratification of human kidney samples by DKD prevalence and disease-relevant measures such as kidney function, proteinuria, and fibrosis, underscoring the relevance of the sGC pathway to patients.


Subject(s)
Diabetes Mellitus , Diabetic Nephropathies , Humans , Rats , Animals , Soluble Guanylyl Cyclase/metabolism , Soluble Guanylyl Cyclase/pharmacology , Soluble Guanylyl Cyclase/therapeutic use , Diabetic Nephropathies/drug therapy , Diabetic Nephropathies/pathology , Guanylate Cyclase/genetics , Guanylate Cyclase/metabolism , Guanylate Cyclase/pharmacology , Kidney/metabolism , Fibrosis
4.
Tierarztl Prax Ausg G Grosstiere Nutztiere ; 45(5): 290-295, 2017 Oct 17.
Article in English | MEDLINE | ID: mdl-28933507

ABSTRACT

OBJECTIVE: Being confronted with a case series of renal neoplasia in several horses which was in striking divergence to literature data, we recognized the need of a retrospective study to assess the presence of renal neoplasms in horses. MATERIAL AND METHODS: Anamnestic animal data, necropsy findings and results of histological and immunohistochemical examinations from 2010 through 2015 were collected and evaluated regarding renal neoplasia. RESULTS: Data from postmortem examinations of 1069 horses revealed 20 horses with renal tumors constituting a prevalence of 1.87 %. Primary renal neoplasms built the majority of cases (n = 15; 75 % of total renal neoplasms) and comprised nine renal carcinomas, four renal adenomas, one renal neuroendocrine tumor and a single nephroblastoma. Among the five secondary renal neoplasms lymphosarcoma was most common (3/5). Remaining metastatic tumors comprised one melanoma and one hemangiosarcoma. No breed or sex predilections were noticeable. Except for the case of nephroblastoma in a stillborn foal, all horses presenting with renal tumors were more than 10 years of age, often older than 20 years. Anamnestic data and clinical symptoms were inconclusive and not assigned to renal disease in most cases. Merely one horse with renal carcinoma presented with renal insufficiency and two horses showed signs of shock due to severe bleeding after tumor capsule rupture in renal carcinoma. CONCLUSION AND CLINICAL RELEVANCE: Renal tumors occur more often than anticipated, especially in older horses. Contradictorily to the literature, primary renal tumors significantly outnumbered secondary neoplasms in this study.


Subject(s)
Horse Diseases/epidemiology , Kidney Neoplasms/veterinary , Age Distribution , Animals , Horses , Kidney Neoplasms/epidemiology , Kidney Neoplasms/secondary , Prevalence , Retrospective Studies
5.
Pediatr Rheumatol Online J ; 15(1): 27, 2017 Apr 13.
Article in English | MEDLINE | ID: mdl-28407779

ABSTRACT

BACKGROUND: Although it is common clinical practice to treat children with Juvenile Idiopathic Arthritis (JIA) with functional appliances, the scientific evidence for this is limited. The aim of this study was to study the histologic effects of mandibular protrusion splints in temporomandibular joint (TMJ) arthritis in rabbits. METHODS: Twenty-eight ten-week old New Zealand white rabbits were randomly divided into four groups: AO (TMJ arthritis, no splint), AS (TMJ arthritis, mandibular splint advancement), OS (no arthritis, mandibular splint advancement) and OO (no arthritis, no splint). TMJ arthritis was induced in the groups AO and AS; 1 week later mandibular protrusion splints were placed on the upper incisors of the AS and OS animals. After 60 days the animals were sacrificed and a semiquantitative histologic evaluation of each TMJ was carried out to analyze the amount of inflammation and bone modeling. RESULTS: AO and AS animals had a higher inflammation score (AO = 1.3; AS = 1.8) than the non-arthritis groups (OO = 0.6; OS = 0.4). Whereas in the untreated control (OO) the amount of apposition and resorption was almost in balance (+1), OS animals displayed significantly more apposition (+9) and AO animals significantly more resorption (-3) than the untreated control. Arthritis animals with protrusion appliances (AS), however, had remarkably more bone apposition (+3) than resorption, indicating a similar bony reaction as in healthy animals, although reduced in extent. CONCLUSIONS: Mandibular advancement in rabbits with TMJ arthritis is possible without detrimental histologic reactions and appears to partially compensate for the bone loss seen in rabbits with TMJ arthritis but without protrusion splints.


Subject(s)
Arthritis, Experimental/therapy , Bone Resorption/pathology , Inflammation/pathology , Mandibular Advancement/instrumentation , Splints , Temporomandibular Joint Disorders/therapy , Temporomandibular Joint/pathology , Animals , Antigens/adverse effects , Arthritis, Experimental/chemically induced , Arthritis, Experimental/pathology , Bone Remodeling , Bone Resorption/etiology , Mandibular Advancement/adverse effects , Ovalbumin/adverse effects , Rabbits , Splints/adverse effects , Temporomandibular Joint Disorders/pathology
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