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Tissue engineering aims to restore or replace different types of biological tissues through the association of cells, biologic factors and biomaterials. Currently, stem cells arise as a major cell source for many therapeutic indications, and their association with 3D scaffolds allow increasing regenerative medicine efficiency. In this context, the use of RNA interference to enhance or control stem cell differentiation into the desired phenotype appears as a promising strategy. However, achieving high transfection efficiency of cells in a 3D structure requires the use of a vector allowing for the spatiotemporally controlled release of the genetic material from these scaffolds. In this study, we report a new siRNA nanovector, called solvent exchange lipoplexe formulation (SELF), which has a tunable size, is stable over time in cell culture conditions and possess a high efficiency to transfect primary human mesenchymal stromal cells (hMSC). We associated SELFs with porous 3D collagen microspheres and demonstrated that the loading capacity and release kinetics were different depending on the size of the associated SELF. Interestingly, these different release profiles resulted in differences in the transfection kinetics of hMSCs. This original and unique type of gene activated matrix, with adaptable release kinetics, could be of interest for long-term and/or sequential transfection profiles of stem cells in 3D culture. STATEMENT OF SIGNIFICANCE: This work combines the use of human mesenchymal stromal cell (hMSC) and gene therapy for tissue engineering. Here, a gene-activated matrix was elaborated with collagen microspheres supporting hMSCs and acting as a reservoir for transfection vectors. This injectable GAM allows for the local and sustained delivery of nucleic acids, hence long-lasting transfection of the supported cells. With the original synthesis protocol presented herein, the size of the nanocarriers can be easily adapted, resulting in different siRNA release profiles from the microspheres. Most interestingly, different siRNA release profiles gave rise to different cell transfection profiles as assessed by the downregulation of a target gene. This highlights the versatility of the system and its suitability for various pathophysiological needs in regenerative medicine., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022. Published by Elsevier Ltd.)

Articular cartilage is made of chondrocytes surrounded by their extracellular matrix that can both sense and respond to various mechanical stimuli. One of the most widely used in vitro model to study cartilage growth is the model of mesenchymal stromal cells-derived cartilage micropellet. However, mechanical stimulation of micropellets has never been reported probably because of their small size and imperfect round shape. The objective of the study was to develop an original custom-made device allowing both the mechanical stimulation and characterization of cartilage micropellets. The fluidic-based device was designed for the concomitant stimulation or characterization of six microspheres placed into the conical wells of a tank. In the present study, the device was validated using alginate-, collagen- and crosslinked collagen-based microspheres. Different types and ranges of pressure signals (square, sinusoidal and constant) were applied. The mechanical properties of microspheres were equivalent to those determined by a conventional compression test. Accuracy, repeatability and reproducibility of all types of pressure signals were demonstrated even though square signals were less accurate and sinusoidal signals were less reproducible than the others. The interest of this new device lies in the reliability to mechanically stimulate and characterize microspheres with diameters in the range of 900 to 1500 μm. Mechanical stimulation can be performed on six microspheres in parallel allowing the mechanical and molecular characterization of the same group of cartilage micropellets. The device will be useful to evaluate the growth of cartilage micropellets under mechanical stimuli., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Phenylketonuria (PKU) is an inherited metabolic disease affecting about one birth out of 15 000. From 1978, a national systematic neonatal screening was set up in France with a regional organisation. French rational and guidelines have been established by the national PKU group with the collaboration of all the physicians responsible for the regional centres. These guidelines specify the minimal diagnosis procedures leading to an optimal treatment of all patients. A low-phenylalanine diet must be started as soon as possible in the neonatal period for all newborns whose phenylalanine levels are above 10 mg/dl. The dietary control must keep the phenylalanine plasma levels between 2 and 5 mg/dl until 10 years of age. After this age, several data argue for a progressive and controlled relaxation of the diet, keeping the phenylalanine level below 15 mg/dl until the end of the adolescence and below 20 to 25 mg/dl in adulthood. All PKU patients must be followed up for life, in order to screen those who may not bear the diet relaxation and in order to strictly prevent maternal PKU deleterious consequences.

Villous atrophy in an infant immediately suggests food intolerance. We report a case with an unusual cause. This female infant was first examined at 5 months for anorexia and failure to thrive. Intestinal biopsy showed total villous atrophy. A diet excluding gluten and cow milk proteins failed to improve her condition and the infant was hospitalized at 7 months for further investigations. The infant was hypotonic with a head lag. No other clinical sign was noted. Serum transaminases were increased 5- to 10-fold and CSF proteins concentration was increased. Metabolic investigations revealed hyperlactacidaemia and an increased lactate/pyruvate ratio during fasting and feeding, suggesting a mitochondrial cytopathy. Respiratory chain enzymatic activity measurements confirmed the diagnosis and showed severely decreased activities of complexes I, III and IV in both the liver and muscle. Molecular analysis demonstrated depletion of mitochondrial DNA in the liver (75%) and in muscle (97%). The infant was discharged under continuous enteral nutrition. Improvement was of short duration and the infant died at 1 year of age of massive hepatic failure. This is the first report of a mitochondrial DNA depletion with total villous atrophy and malabsorption as early clinical onset. A mitochondrial cytopathy should be considered in such conditions when food exclusion diets fail.

Background: We tested the hypothesis that no right-sided dominance exists after infrastellate surgical upper-thoracic sympathectomy. We aimed to confirm whether a significant bradycardia was constant and only dependent on the right side., Methods: We performed 24-hour Holter electrocardiographic recordings in 12 patients referred for bilateral sympathectomy. Surgery was performed at two distinct times allowing for the study of the consequences of unilateral right and bilateral sympathectomy., Results: Heart rate was 77 +/- 8 beats per minute before surgery on the 24-hour recording and significantly decreased after bilateral (67.8 +/- 6.5 beats per minute; p < 0.05) but not after unilateral right sympathectomy. Consistently spectral analysis variables significantly changed after bilateral surgery but showed no right-sided dominance. Little effect of sympathectomy was found on the QT interval, which tended to decrease after bilateral sympathectomy., Conclusions: Patients should be informed of the bradycardia resulting from sympathectomy. No right-sided dominance can be found consistently with the random distribution of substellate cardiac fibers reported in anatomic studies.

Purpose: Update of recent works on polymyalgia rheumatica (PMR). CURRENT KNOWLEDGE ANS KEY POINTS: In polymyalgia rheumatica (PMR) unassociated with giant cell arteritis (GCA) (twice as frequent as GCA without PMR) several recent works demonstrated by MRI or echography that synovitis and/or subacromial bursitis accounted for most of the painful shoulders and could be relieved by steroid injections. Peripheral synovitis can also occur in 10-20% of PMR, and lead to consideration of other diagnoses, mostly RA or the RS3PE syndromes for those cases of PMR with peripheral edema. PMR with asymmetrical onset are often difficult to diagnose early, and the classification criteria for PMR are not widely accepted. When clinical signs suggestive of GCA are lacking, temporal biopsy is positive in only 1 to 5% of PMR cases. Several studies on PMR with so-called 'normal' ESR (below 30 mm, first hour) have cast doubts on the value of this biological sign (although 'normal ESR' should only stand for values below 11 mm). Hence it would be worthwhile to study whether CRP and even SAA deserve to be added to future sets of criteria for PMR. A defect in hypothalamic axis response is often noticed and could play a part in PMR pathogenesis, thus explaining why PMR is quite exclusively noticed after ages 50 or 60. Two-thirds of patients can stop prednisone within 2 years after the onset of treatment. The lack of a prompt response within the first days should suggest differential diagnoses, including some myelodysplastic disorders., Future Prospects and Projects: The search for genetic factors common or specific to PMR and GCA could enhance our understanding of these overlapping syndromes. Studies of the transcriptosomes of lymphocytes infiltrating the target tissues (arterial wall in GCA, synovium in PMR) might also prove informative. Controlled studies of new biological treatments like cytokine inhibitors (anti-TNF-alpha, anti-interferon gamma) could demonstrate a clear sparing effect in steroids, a goal not yet achieved by the use of current DMARDs, including MTX.

Background: In France, neonatal screening of phenylketonuria (PKU) started in 1966. A national association was created in 1978 in order to organise the neonatal screening program and to control the efficacy of the screening and patients' follow-up., Aims: To evaluate the results of the French PKU screening program in terms of hyperphenylalaninaemia epidemiology, efficacy of the screening procedure, management and outcome of the patients., Study Design: The national database has been filled-up first with the answers to questionnaires that were sent each year by the PKU patients' physicians, and second with the results of an additional inquiry, which was set up in 1994 in order to investigate diagnosis, treatment, and school outcome of all French PKU patients., Results: PKU was diagnosed in 81.6% of patients with hyperphenylalaninaemia (HPA), non-PKU HPA in 17.2% and cofactor deficiency in 1.1%. From 1980, incidence of PKU has been stable: 1 per 17,124 live births. Sensitivity of the screening procedure was 99.3%. Age at diet initiation regularly decreased to reach 14 days as a median in 1996. Until 1990, median age at diet discontinuation was 6 years of age. Later, strict diet was continued longer (at least, up to 8-10 years). PKU patients who entered to secondary school at normal age were characterised by an earlier age at diagnosis and at diet initiation and a later age at diet discontinuation, compared to those who entered 1 year or more behind normal age., Conclusion: These data confirm the benefit of a nationwide organised screening program. They emphasise the importance of an early neonatal diagnosis and diet initiation in PKU patients and are consistent with the benefit of a longer period of strict diet in childhood.

Background: Parathyroidectomy is unsuccessful in 10-30% of uraemic patients operated on for secondary hyperparathyroidism. We investigated the usefulness of preoperative radionuclide imaging, with simultaneous recording of the distribution images of iodine-123 and technetium-99m-labelled sestamibi., Methods: 11 patients with secondary hyperparathyroidism underwent prospective imaging and parathyroidectomy. Plasma concentrations of intact parathyroid hormone (PTH) were measured in all patients before and 6 months after subtotal parathyroidectomy., Findings: Preoperative scanning showed 42 hot-spots suggesting enlarged parathyroid glands. 45 glands were discovered at surgery, and the parathyroidectomy was deemed successful in ten patients. Among the latter, one patient had a supernumerary parathyroid gland detected by scanning and resected from the left thymus. Another patient showed ectopic uptake corresponding to a large parathyroid gland in the upper mediastinum, and another had a parathyroid gland well above the thyroid. No false-positive scan findings were documented. In the patient for whom parathyroidectomy failed, preoperative scanning suggested five enlarged parathyroid glands, though the surgeon found only four glands, in their normal positions. Hyperparathyroidism persisted (intact PTH 527 ng/L, 6 months after surgery). A second scan confirmed the preoperative scan, showing a fifth parathyroid gland in the middle of the right thyroid lobe., Interpretation: Simultaneous recording of 99mTc-sestamibi and 123I improved the imaging of parathyroid glands in secondary hyperparathyroidism. The technique can identify ectopic and supernumerary parathyroid glands.

This paper examines the validity of using ecologic measures of socioeconomic status as proxies for individual-level measures in the study of population health. Based on a representative 5% sample of households in a Canadian province, the study integrated three sources of information: administrative records of individual health care utilization, records of deaths and 1986 census records which contained information on household income and average neighbourhood income. Thirteen measures of health status were developed from these sources of information. The hypothesis that risk estimates derived from ecologic income measures will be attenuated relative to estimates obtained from household income was not supported. These results provide evidence for the use of ecologic-level measures of income in studies which do not have access to individual-level income measures.

Brain abscesses and empyemas are severe infections with lethal outcomes in the case of inappropriate treatment. The files of 34 patients with brain abscesses, and nine with intracranial empyemas treated over eight years (1990-1997) were analyzed retrospectively. Cases were evaluated for treatment and compared with data from the literature. Patients with brain abscess underwent either aspiration of the lesion through a burr hole (79.5% of the cases), or craniotomy and excision (8.8% of the cases); 11.7% were treated only with antibiotics. The operative mortality was 2.9% and the outcome was satisfactory in 85% of patients. These results are in agreement with data from the literature. Prognosis is strongly related to the initial clinical status. Current methods of treatment include surgical aspiration of large abscesses with a mass effect, and are usually associated with a poor clinical status. Excision is suggested whenever aspiration procedures have failed, or in the presence of foreign material or fungal abscess. Medical treatment is indicated for small and deeply located abscesses in patients with satisfactory clinical states. Empyemas in our series were treated with burr hole and pus aspiration. The mortality rate was 11%, and 62.5% of the patients made a good recovery. In agreement with other reported studies, the method of treating subdural empyema is much less significant than an aggressive early drainage of the infection. Although brain abscesses and empyema remain a significant neurosurgical concern, aggressive treatment can result in an excellent outcome in the majority of patients.

Two patients with palindromic rheumatism were diagnosed with Whipple's disease 5 years after onset of the joint symptoms. Twenty-one previously published cases of Whipple's disease with palindromic rheumatism as the first manifestation were identified. Statistically significant differences were found between palindromic rheumatism in patients with and without Whipple's disease. Patients with Whipple's disease were more likely to be male and to exhibit fever and elevated erythrocyte sedimentation rates during joint symptom flares, whereas they were less likely to have involvement of the metacarpophalangeal and proximal interphalangeal joints. None of the patients with Whipple's disease had either skin manifestations of palindromic rheumatism (nodules or paraarthritis) or positive tests for rheumatoid factor. Patients with palindromic rheumatism exhibiting these features should have an intestinal biopsy to look for Whipple's disease.

IgG antibodies to rat esophagus stratum corneum are highly specific for rheumatoid arthritis and have been recently shown to be directed against human (pro)filaggrin. Although the mechanisms underlying the loss of tolerance of B lymphocytes for filaggrin remain unelucidated, a role of infection with the human papillomavirus has been suggested on the basis of the following facts: 1) the protein exhibiting the greatest molecular homology with filaggrin is papillomavirus-encoded; 2) human papillomavirus proteins bind to cytoskeletal proteins; 3) human papillomavirus replication is enhanced by friction and rheumatoid lesions predominantly develop in areas subjected to friction, as shown by the distribution of rheumatoid nodules; 4) the rheumatoid pannus resembles a benign tumor. The objectives of this study were to look for the human papillomavirus genome in six synovial membrane specimens and two rheumatoid nodule specimens from rheumatoid arthritis patients with disease durations of more than ten years and in 20 synovial membrane specimens collected during surgical procedures in osteoarthritis patients. The methods used were polymerase chain reaction with papillomavirus-specific primers. The papillomavirus genome was not detected in any of the 28 specimens. A role for the human papillomavirus in the pathogenesis of rheumatoid arthritis cannot be ruled out on the basis of these findings because filaggrin is expressed in other tissues, including the thymic medulla epithelium. In addition, the primers used in this study may have been inappropriate.

A new method of bromine number determination appropriate to heavy-ends petroleum is reported. This method, which uses an electrochemical titration and tetrabutylammonium tribromide as reagent, has been tested on Boscan atmospheric residues. The titration of the unreacted tribromide ions and of the bromide ions produced enables the proportion of the bromine addition to multiple bonds and the proportion of substitution reactions with aromatic compounds (phenols, amines, etc.) to be estimated. The sensitivity and reproducibility of this easy method are both good.

The partial correction of anemia with recombinant human erythropoietin (rHuEpo) is frequently associated with an increase in arterial pressure and could oppose the beneficial effect of anemia correction on myocardial function. In order to analyze the influence of rHuEpo therapy on the vessels and the heart, we performed systemic and regional hemodynamics studies in 11 hemodialysis patients before and 10 to 35 weeks after initiation of rHuEpo therapy, when hemoglobin concentration was 6.8 +/- 0.9 and 10.6 +/- 0.66 g/dl (mean +/- SD), respectively. The mean arterial pressure remained unchanged during this period (88 +/- 21 vs. 88 +/- 15 mm Hg). Echocardiographic study showed that rHuEpo treatment led to a decrease in left ventricular end-diastolic diameter (4.9 +/- 0.5 vs. 5.1 +/- 0.6 cm; P less than 0.03), left atrial diameter (3.22 +/- 0.30 vs. 3.43 +/- 0.33; P less than 0.03), and left ventricular mass index (109.8 +/- 30.6 vs. 133 +/- 30.8 g/m2; P less than 0.05). Left ventricular ejection volume decreased from 86 +/- 24 to 75 +/- 19 ml (P less than 0.03) and heart rate from 76 +/- 9 to 70 +/- 10 beats/min (P less than 0.05). Cardiac index decreased from 4715 +/- 700 to 3635 +/- 444 ml/min/m2 (P less than 0.01) and peripheral resistances rose from 1480 +/- 162 to 1943 +/- 250 dynes.sec.cm-5.m2 (P less than 0.01). Fractional ejection and mean circumferential fiber shortening remained unchanged. The treatment with rHuEpo did not change the aortic diameters.(ABSTRACT TRUNCATED AT 250 WORDS)