Correlation between magnetic resonance, X-ray imaging alterations and histological changes in an ovine model of age-related disc degeneration.

Sheep are one of the many animal models used to investigate the pathophysiology of disc degeneration and the regenerative strategies for intervertebral disc (IVD) disease. To date, few studies have thoroughly explored ageing of ovine lumbar IVDs. Hence, the objective of the present study was to concomitantly assess the development of spontaneous age-related lumbar IVD degeneration in sheep using X-ray, magnetic resonance imaging (MRI) as well as histological analyses. 8 young ewes (< 48 months old) and 4 skeletally mature ewes (> 48 months old) were included. Disc height, Pfirrmann and modified Pfirrmann grades as well as T2-wsi and T2 times were assessed by X-ray and MRI. The modified Boos score was also determined using histology sections. Pfirrmann (2 to 3) and modified Pfirrmann (2 to 4) grades as well as Boos scores (7 to 13) gradually increased with ageing, while T2-weighted signal intensity (1.18 to 0.75), T2 relaxation time (114.36 to 70.65 ms) and disc height (4.1 to 3.2 mm) decreased significantly. All the imaging modalities strongly correlated with the histology (p < 0.0001). The present study described the suitability of sheep as a model of age-related IVD degeneration by correlation of histological tissue alterations with the changes observed using X-ray and MRI. Given the structural similarities with humans, the study demonstrated that sheep warrant being considered as a pertinent animal model to investigate IVD regenerative strategies without induction of degeneration.

Estimates of Maize Plant Density from UAV RGB Images Using Faster-RCNN Detection Model: Impact of the Spatial Resolution.

Early-stage plant density is an essential trait that determines the fate of a genotype under given environmental conditions and management practices. The use of RGB images taken from UAVs may replace the traditional visual counting in fields with improved throughput, accuracy, and access to plant localization. However, high-resolution images are required to detect the small plants present at the early stages. This study explores the impact of image ground sampling distance (GSD) on the performances of maize plant detection at three-to-five leaves stage using Faster-RCNN object detection algorithm. Data collected at high resolution (GSD ≈ 0.3 cm) over six contrasted sites were used for model training. Two additional sites with images acquired both at high and low (GSD ≈ 0.6 cm) resolutions were used to evaluate the model performances. Results show that Faster-RCNN achieved very good plant detection and counting (rRMSE = 0.08) performances when native high-resolution images are used both for training and validation. Similarly, good performances were observed (rRMSE = 0.11) when the model is trained over synthetic low-resolution images obtained by downsampling the native training high-resolution images and applied to the synthetic low-resolution validation images. Conversely, poor performances are obtained when the model is trained on a given spatial resolution and applied to another spatial resolution. Training on a mix of high- and low-resolution images allows to get very good performances on the native high-resolution (rRMSE = 0.06) and synthetic low-resolution (rRMSE = 0.10) images. However, very low performances are still observed over the native low-resolution images (rRMSE = 0.48), mainly due to the poor quality of the native low-resolution images. Finally, an advanced super resolution method based on GAN (generative adversarial network) that introduces additional textural information derived from the native high-resolution images was applied to the native low-resolution validation images. Results show some significant improvement (rRMSE = 0.22) compared to bicubic upsampling approach, while still far below the performances achieved over the native high-resolution images.

[Atypical localization of a glomus tumor]. / Une tumeur glomique de localisation atypique.

Glomous tumors are rare and benign, generally affecting the fingers. Other localizations have nevertheless been described. We report the case of a patient who presented a supra-patellar glomous tumor provoking a pain-induced limp. Magnetic resonance imaging confirmed the diagnosis. The patient underwent complete surgical resection of the tumor followed by total resolution of the pain. Glomous tumors in an atypical localization may go unnoticed, with the risk of late or erroneous diagnosis. Symptoms are easily resolved with simple resection.

A multi-structured epidemic problem with direct and indirect transmission in heterogeneous environments.

In this work, we analyse a deterministic epidemic mathematical model motivated by the propagation of a hantavirus (Puumala hantavirus) within a bank vole population (Clethrionomys glareolus). The host population is split into juvenile and adult individuals. A heterogeneous spatial chronological age and infection age structure is considered, and also indirect transmission via the environment. Maturation rates for juvenile individuals are adult density-dependent. For the reaction-diffusion systems with age structures derived, we give global existence, uniqueness and global boundedness results. A model with transmission to humans is also studied here.

Family history of hypertension, anthropometric parameters and markers of early atherosclerosis in young healthy individuals.

The predisposition to thrombogenesis is increased in essential hypertension, and hypertensive patients are prone to develop more vulnerable atherosclerotic plaques. To evaluate the possible influence of family history of hypertension on some indicators of early atherosclerosis, we studied eighty-five healthy normotensive individuals with (FH+) or without (FH-) family history of essential hypertension by measuring metabolic profile and concentrations of P-selectin, interleukin 6 and matrix metalloproteinase (MMP)-2, MMP-9, and tissue inhibitor of metalloproteinase (TIMP)-1. In a subset of individuals, MMP-9 activity was assessed in monocytes by zymography, and TIMP-1 expression by western blot. As compared with FH- individuals, FH+ individuals had significantly higher P-selectin but similar interleukin-6 levels. Although no difference was observed in MMP-2 levels between the two groups, MMP-9 and TIMP-1 were higher in FH+ individuals, who also had higher intracellular MMP-9 levels and TIMP-1 protein expression. P-selectin (r=-0.32; P<0.01), MMP-9 (r=-0.37; P<0.001) and TIMP-1 (r=-0.23; P<0.05) levels were inversely related to high density lipoprotein (HDL) cholesterol. P-selectin was also directly related to serum triglycerides (r=0.30; P<0.01). We conclude that a positive family history of hypertension is associated with an initial increase in markers of inflammation and plaque instability in otherwise healthy young normotensive individuals, likely conveying a predisposition to develop early atherothrombosis.

No need to open the jar: a comparative study of Magnetic Resonance Imaging results on fresh and alcohol preserved common carps (Cyprinus carpio (L. 1758), Cyprinidae, Teleostei).

Magnetic Resonance Imaging (MRI) examinations have been conducted both on fresh and alcohol-preserved common carps (Cyprinus carpio). The images have been compared to those of a sagittally-cut frozen animal of the same species. This work shows that the images obtained are globally similar, and that the MRI technique can be applied to investigate the gross anatomy of alcohol-preserved specimens without destroying them. Unfortunately, this kind of study does not provide precise enough anatomical data for small specimens (less than 10 cm in total length) with a 1 Tesla magnetic field. Nevertheless, leaving the specimen in the jar during MRI examinations does not affect the quality of the final images.

Effect of statins on soluble CD40 ligand in hypercholesterolemic Type 2 diabetic patients.

Hypercholesterolemia and Type 2 diabetes are well-recognized risk factors for cardiovascular disease, promoted by a condition of subclinical inflammation and a hypercoagulable state. Soluble CD40 ligand (sCD40L), a marker of vascular inflammation, seems to predict vascular damage in patients with Type 2 diabetes. Beside the lipid-lowering effect, statins seem to slow the progression of atherosclerosis through a series of anti-inflammatory effects, including a reduction of sCD40L levels. This study compared the effect of a short-term (12 weeks) treatment with rosuvastatin or simvastatin on some markers of inflammation in 36 patients with Type 2 diabetes and moderate hypercholesterolemia. As expected, both drugs significantly modified lipid profile; moreover, rosuvastatin and simvastatin were both able to significantly reduce albumin excretion rate in these patients, without affecting urinary N-acetyl-beta-D-glucosaminidase. Serum homocysteine was not influenced by the treatment, as interleukin-6 levels, while C reactive protein diminished; moreover, rosuvastatin, but not simvastatin, was able to significantly reduce sCD40L. The only clinical parameter related with the variations in sCD40L was systolic blood pressure. In hypercholesterolemic Type 2 diabetic patients, sCD40L, a factor playing a pivotal role in the pathogenesis of atherosclerosis and associated with more rupture-prone lesions, is reduced by short-term treatment with rosuvastatin.

Effects of different LDL particles on inflammatory molecules in human mesangial cells.

AIMS/HYPOTHESIS: Inflammation is a mechanism of glomerular damage in chronic glomerulopathies. LDL may increase the production of inflammatory cytokines in renal tissues. However, the relative role of native, oxidised and glycated LDL in promoting this process has been only partially elucidated. METHODS: We tested the inflammatory and proapoptotic effects of native, oxidised and glycated LDL in human mesangial cells (HMCs) by measuring levels of IL6, CD40 and macrophage migration inhibitory factor (MIF) genes, MIF protein, release of IL6, soluble CD40, fibronectin and laminin, early and late apoptosis, and extracellular regulated kinases (ERK) 1/2 and c-Jun N-terminal kinase (JNK) activation. RESULTS: IL6 and CD40 mRNA were dose-dependently upregulated by all three species; this was closely paralleled by their increased release. MIF mRNA was potently stimulated by modified LDL, as confirmed by immunostaining. Fibronectin and laminin release was stimulated by both oxidised and glycated, but not native, LDL. All LDL species induced some increase in late, but not early, apoptosis, and similarly activated JNK2/3 phosphorylation; in contrast, ERK1/2 phosphorylation was more strongly upregulated by oxidised than either native or glycated LDL. CONCLUSIONS: In HMCs, the production and release of IL6 and CD40 is stimulated by both native and modified LDL, while MIF is more strongly stimulated by oxidised LDL. Regarding the pattern of mesangial expansion, fibronectin and laminin are upregulated by oxidised and glycated LDL. Apoptosis, if modest, is induced by all species. Intracellular signalling of native and modified LDL involves JNK2/3 and, perhaps more specifically, ERK1/2. Tight control of the lipid profile may be useful in preserving kidney function in patients with metabolic alterations.

Effect of short-term treatment with meloxicam and pimobendan on the renal function in healthy beagle dogs.

The aim of the study was to investigate the renal function in clinically normal dogs receiving meloxicam and pimobendan alone or in combination. Ten adult female beagle dogs were administered the treatment for 7 days in a randomized crossover trial (control/meloxicam/pimobendan/meloxicam and pimobendan). Renal function was assessed by blood urea, creatinine, sodium, potassium and chloride concentrations and by glomerular filtration rate, measured by means of renal scintigraphy [renal uptake of (99m)Tc-diethylenetriaminepentacetic acid (DTPA)] and plasma clearance of (99m)Tc-DTPA. As compared with the control group, renal uptake and plasma clearance of (99m)Tc-DTPA were not significantly modified after a 7-day period of treatment with meloxicam or pimobendan alone, or meloxicam and pimobendan in combination. Furthermore, urea, creatinine, sodium, potassium and chloride levels in the serum of the dogs during the 7-day period treatment were not significantly modified in relation to the treatments. It was therefore concluded that meloxicam and pimobendan alone or in combination did not alter renal function in healthy dogs.

Pattern of expression of adiponectin receptors in human adipose tissue depots and its relation to the metabolic state.

OBJECTIVE: To investigate whether adiponectin receptor genes (AdipoR1 and AdipoR2) expression in human subcutaneous (SAT) and visceral (VAT) adipose tissue in severely obese patients with or without diabetes is related to adiponectin gene (APM1) expression and in vivo metabolic parameters. DESIGN: Cross-sectional, clinical research study. SUBJECTS: Total RNA was extracted from SAT and VAT tissue obtained during surgery from 13 lean controls, 30 obese diabetic patients, 19 obese glucose-intolerant patients and 54 obese subjects with normal glucose tolerance. MEASUREMENTS: Tissue expression of APM1, AdipoR1 and AdipoR2, tissue concentration of adiponectin (ApN), and metabolic variables. RESULTS: APM1 expression was higher in SAT than VAT (1.06+/-0.76 vs 0.69+/-0.52, P<0.0001) as was AdipoR1 (1.17+/-0.70 vs 0.66+/-0.38, P<0.0001) and AdipoR2 (7.02+/-6.19 vs 0.75+/-0.64, P<0.0001). In SAT, APM1 and AdipoR1 expression tended to be lower - by 0.38+/-0.22 and 0.35+/-0.22, respectively - and AdipoR2 expression was markedly depressed - by 4.82+/-1.93 - in association with obesity, whereas presence of diabetes had no additional effect. In VAT, APM1 and AdipoR1 expressions were also reduced - by 0.36+/-0.16 and 0.30+/-0.11, respectively - in association with obesity. Within both SAT and VAT, expression levels of APM1, AdipoR1 and AdipoR2 were all positively interrelated. Tissue ApN concentrations in SAT were similar across groups, whereas ApN levels in VAT were substantially lower in association with obesity (by an average of 63+/-12 ng/mg total protein, P<0.0001). In multivariate models adjusting for sex, age and obesity, serum triglyceride concentrations were reciprocally related to APM1 (r=-0.27, P<0.02), AdipoR1 (r=-0.37, P<0.002 and AdipoR2 expression (r=-0.37, P<0.002) in VAT. Likewise, plasma insulin concentrations were inversely related only to APM1 in VAT (r=-0.25, P<0.03). CONCLUSIONS: Severe obesity is associated with suppressed expression of both ApN and its receptors in both SAT and VAT, the expression levels in VAT are specifically linked with hyperinsulinemia and dyslipidemia.

Effect of tepoxalin on renal function in healthy dogs receiving an angiotensin-converting enzyme inhibitor.

The objective of this study was to investigate renal function in clinically normal dogs receiving tepoxalin, a nonsteroidal inflammatory drug, either in association with or without an angiotensin-converting enzyme inhibitor (ACEI). Ten adult female Beagle dogs were used in the three phases of the study. The dogs were administered the drugs once daily for 7 days (experiment 1: placebo/tepoxalin/tepoxalin and benazepril; experiment 2: enalapril/tepoxalin and enalapril) or for 28 days (experiment 3: tepoxalin and benazepril together). Renal function was assessed by measurement of glomerular filtration rate (GFR) by renal scintigraphy [(renal uptake of 99mTc-diethylenetriaminepentacetic acid (DTPA)] and plasma clearance of 99mTc-DTPA. Compared with the placebo group, renal uptake and plasma clearance of 99mTc-DTPA were not significantly modified after a 7-day period of treatment with tepoxalin or enalapril alone, tepoxalin and benazepril or tepoxalin and enalapril together. No significant change was obtained in GFR after a 28-day period of dosing with tepoxalin and benazepril together. Therefore, it was concluded that tepoxalin did not alter renal function in healthy Beagle dogs receiving ACEI.

TEM-89 beta-lactamase produced by a Proteus mirabilis clinical isolate: new complex mutant (CMT 3) with mutations in both TEM-59 (IRT-17) and TEM-3.

TEM-89 (CMT-3) is the first complex mutant beta-lactamase produced by a clinical strain of Proteus mirabilis (strain Pm 631). This new enzyme, which has a pI of 6.28, is derived from TEM-3 and has a single amino acid substitution also encountered in TEM-59 (inhibitor-resistant TEM beta-lactamase IRT-17): Ser-130 to Gly. TEM-89 hydrolyzed penicillins to the same extent that TEM-3 did but lost almost all hydrolytic activity for cephalosporins and, like TEM-59, was highly resistant to inhibitors.

Characterization of TEM-56, a novel beta-lactamase produced by a Klebsiella pneumoniae clinical isolate.

TEM-56 produced by a Klebsiella pneumoniae clinical isolate is a novel beta-lactamase of isoelectric point 6.4 that confers a moderate resistance level to expanded-spectrum cephalosporins. The amino acid sequence deduced from the corresponding bla gene showed two amino acid replacements with respect to the TEM-2 sequence: Glu-104 to Lys and His-153 to Arg. This enzyme showed catalytic properties close to those of TEM-18. Thus, TEM-56 appears as a new TEM mutant, an intermediary between TEM-18 and the extended-spectrum beta-lactamase TEM-21.