Molecular B-cell clonality assay in minor salivary glands as a useful tool for the lymphoma risk assessment in Sjögren's syndrome.

OBJECTIVES: Non-Hodgkin's lymphoma (NHL) risk assessment is crucial in Sjögren's syndrome (SS). We studied the prevalence of clonal immunoglobulin gene rearrangements in minor salivary glands (MSG) and their correlations with lymphoma occurrence and with previously established NHL predictors. METHODS: Molecular B-cell expansion was studied in fresh-frozen MSG of 207 patients with either suspected SS or with suspected lymphoma during SS, using a standardised multiplex PCR assay combined with heteroduplex analysis by microcapillary electrophoresis. The assignation of clonal cases was based on EuroClonality consortium guidelines. RESULTS: Among 207 studied patients, 31 (15%) had MSG monoclonal B-cell infiltration. Monoclonality was significantly more frequent in patients with SS (28/123, 22.8%) compared with patients without SS (3/84, 3.6%, P<0.001). Monoclonal B-cell infiltration in MSG of SS patients correlated significantly with ongoing salivary gland NHL, salivary gland swelling, CD4+ T-cell lymphopenia, rheumatoid factor (RF) activity, low complement levels and type 2 mixed cryoglobulinemia. The accumulation of biological risk factors was associated with a higher rate of MSG B-cell monoclonality given that patients with only positive RF had no probability of MSG B-cell monoclonality, RF-positive patients with 1 or 2 other risk factors had a 25.0% and 85.7% probability of MSG B-cell monoclonality, respectively. CONCLUSION: The detection of MSG monoclonal B-cell expansion by this easy-to-perform molecular assay is useful, both at the time of diagnosis and during the course of SS. Monoclonal B-cell expansion is associated with a subset of SS patients presenting either ongoing lymphoma or other established lymphoma predictive factors.

Theoretical study of effect of the geometrical parameters on the dynamic properties of the elastic rings of an air journal bearing.

The paper investigates theoretically the effect of the geometry of the elastic rings of an air journal bearing on the elastic rings dynamic coefficients. The physical finite element method (FEM) model used to obtain the dynamic coefficients of the rings is discussed. A theoretical model is implemented to predict the effect of the geometrical parameters on the dynamic coefficients of the elastic rings. The effect of the geometrical parameters on the dynamic coefficients at different frequencies is studied using FEM. The elastic geometry that result in desired dynamic coefficients is demonstrated. Since predicting the dynamic coefficients for all possible ring geometries using FEM would be computationally expensive. A neural network (NN) is trained to predict the dynamic coefficients for all possible ring geometries generated by the different ring geometrical parameters within a given input domain. The NN results are compared to the experimentally verified FEM results and the results are in good agreement.

The General Composition of Polyhydroxyalkanoates and Factors that Influence their Production and Biosynthesis.

Polyhydroxyalkanoates (PHAs) have been a current research topic for many years. PHAs are biopolymers produced by bacteria under unfavorable growth conditions. They are biomaterials that exhibit a variety of properties, including biocompatibility, biodegradability, and high mechanical strength, making them suitable for future applications. This review aimed to provide general information on PHAs, such as their structure, classification, and parameters that affect the production process. In addition, the most commonly used bacterial strains that produce PHAs are highlighted, and details are provided on the type of carbon source used and how to optimize the parameters for bioprocesses. PHAs present a challenge to researchers because a variety of parameters affect biosynthesis, including the variety of carbon sources, bacterial strains, and culture media. Nevertheless, PHAs represent an opportunity to replace plastics, because they can be produced quickly and at a relatively low cost. With growing environmental concerns and declining oil reserves, polyhydroxyalkanoates are a potential replacement for nonbiodegradable polymers. Therefore, the study of PHA production remains a hot topic, as many substrates can be used as carbon sources. Both researchers and industry are interested in facilitating the production, commercialization, and application of PHAs as potential replacements for nonbiodegradable polymers. The fact that they are biocompatible, environmentally biodegradable, and adaptable makes PHAs one of the most important materials available in the market. They are preferred in various industries, such as agriculture (for bioremediation of oil-polluted sites, minimizing the toxicity of pollutants, and environmental impact) or medicine (as medical devices). The various bioprocess technologies mentioned earlier will be further investigated, such as the carbon source (to obtain a biopolymer with the lowest possible cost, such as glucose, various fatty acids, and especially renewable sources), pretreatment of the substrate (to increase the availability of the carbon source), and supplementation of the growth environment with different substances and minerals). Consequently, the study of PHA production remains a current topic because many substrates can be used as carbon sources. Obtaining PHA from renewable substrates (waste oil, coffee grounds, plant husks, etc.) contributes significantly to reducing PHA costs. Therefore, in this review, pure bacterial cultures (Bacillus megaterium, Ralstonia eutropha, Cupriavidus necator, and Pseudomonas putida) have been investigated for their potential to utilize by-products as cheap feedstocks. The advantage of these bioprocesses is that a significant amount of PHA can be obtained using renewable carbon sources. The main disadvantage is that the chemical structure of the obtained biopolymer cannot be determined in advance, as is the case with bioprocesses using a conventional carbon source. Polyhydroxyalkanoates are materials that can be used in many fields, such as the medical field (skin grafts, implantable medical devices, scaffolds, drug-controlled release devices), agriculture (for polluted water cleaning), cosmetics and food (biodegradable packaging, gentle biosurfactants with suitable skin for cosmetics), and industry (production of biodegradable biopolymers that replace conventional plastic). Nonetheless, PHA biopolymers continue to be researched and improved and play an important role in various industrial sectors. The properties of this material allow its use as a biodegradable material in the cosmetics industry (for packaging), in the production of biodegradable plastics, or in biomedical engineering, as various prostheses or implantable scaffolds.

Using neural networks to predict the effect of the preload location on the natural frequencies of a cantilever beam.

With the evolution of computational power of computers in 20th century, neural networks (NNs) are becoming more popular in different engineering applications because of its ability to approximate static and dynamic, linear and non-linear, multi-dimensional systems. For example, they are used in industrial processes to automate assembly lines which increases its productivity and in automotive to reduce gas consumption of an engine. In this paper, NNs are utilized to reduce the computational power needed for finite element methods (FEM) simulations. A case study is taken for which NNs are used to predict the effect of the preload position and magnitude on the natural frequencies of the prestressed cantilever beam. A simple FEM model is implemented to generate the data set required to train the NN. The steps done to construct the FEM are discussed and the FEM model results are verified. The effect of the preload position on the natural frequencies of the beam is studied. A NN is then implemented to predict the natural frequencies of the beam for different beam cross-section geometries and different preload magnitudes and positions. The NN architecture, data processing and training methodology are explained. The NN and FEM results are compared to show the accuracy of the NN predictions. The results are shown to be in good agreement.

The Production of Biodegradable Polymers-medium-chain-length Polyhydroxyalkanoates (mcl-PHA) in Pseudomonas putida for Biomedical Engineering Applications.

BACKGROUND: Polyhydroxyalkanoates (PHAs) are bacteria-synthesized biopolymers under imbalanced growth conditions. These biopolymers are acknowledged as potential biomaterials for future applications because of their characteristics of biocompatibility and biodegradability, and ability to be produced rapidly, and strong functionality of mechanical resistance. This article aims to perform microbial fermentation using the Pseudomonas putida strain to identify the quantity of biopolymers, particularly of the medium-chain-length (mcl-PHA) polyhydroxyalkanoates, based on the type and quantity of the added precursors (glucose and fatty acids). METHODS: To understand the microbial interaction and the mechanism involved in PHA biosynthesis, several methods were employed and microbial biomass was obtained using the Pseudomonas putida strain capable of producing PHA. The polymer production by acetone extraction was analyzed using the Soxhlet method, while the biopolymer purification was done via the methanol-ethanol treatment, after which the biomass estimation was done through spectrophotometric analysis. This was followed by measuring the dry weight of the cells and quantification of the biopolymer produced using the gas chromatography method (GC). RESULTS: The highest PHA yield was obtained using the octanoic (17 mL in 2000 mL medium) and hexanoic acids (14 mL in 2000 mL medium) as the precursors. As a result, the octanoic acid - octanoic acid, heptanoic acid - nonanoic acid, and octanoic acid - hexanoic acid were identified as the different precursors that supported the quantity of PHA obtained. CONCLUSION: Among the 4 types of structurally related substrates, the Pseudomonas putida ICCF 319 strain showed a preference for the C8 sublayer for the biosynthesis of the elastomeric PHAs composed predominantly of more C8 monomers than the C6 and C10.

Partially reversible cortical metabolic dysfunction in familial hemiplegic migraine with prolonged aura.

We report a SPECT and PET voxel-based analysis of cerebral blood flow and metabolic rate for glucose in a 23-year-old woman with familial hemiplegic migraine (FHM) caused by ATP1A2 gene mutation. In comparison with healthy subjects, a PET scan showed brain glucose hypometabolism, controlaterally to the hemiplegia, in the perisylvian area early in the attack (Day 1), without any SPECT perfusion abnormalities. Decrease in metabolic rate was only partially reversible at Day 78, concordant at this time with a remaining hemisensory loss. These findings provide further evidence for a primary cortical metabolic dysfunction in FHM.

Acute polyarthritis revealing hepatitis E.

We report a case of acute hepatitis E occurring in a 51-year-old French woman, revealed by an abrupt onset of polyarthritis involving the ankles and knees followed by the wrists and fingers. Polyarthritis lasted up to 3 months without recurrence. Our case was characterised by a 9-month prolonged viraemia with persistence of specific IgM in the serum. The hepatitis E virus belonged to genotype 3 and may have been contracted in France or during travel to hyperendemic areas. Our case shows that acute polyarthritis could be another systemic manifestation of hepatitis E virus infection.

Multiple cutaneous angiomas and Poems syndrome.

INTRODUCTION: Poems syndrome is characterized by polyneuropathy, organomegaly, endocrinopathy, M-proteins, and skin lesions. CASE: We describe here a case in which the eruption of diffuse cutaneous angiomas in a woman with a history of bone plasmocytoma and progressive polyneuropathy helped physicians to diagnose Poems syndrome. DISCUSSION: Other manifestations of Poems syndrome in this patient included endocrine dysfunction (hypothyroidism, adrenal insufficiency, and hypogonadism), sclerotic bone lesions of the femoral shaft, ribs, and vertebral body, monoclonal gammopathy, and anasarca. Steroid treatment led to dramatic improvement of polyserositis and a generally good outcome, despite persistence of the cutaneous lesions. This case points out this unusual cutaneous manifestation associated with Poems syndrome.

Severe lower limbs lymphedema following breast carcinoma treatment revealing radiation-induced constrictive pericarditis--a case report.

In patients treated for breast carcinoma, unilateral lymphedema of the upper limb is usual. However, to the authors' knowledge, lower limb lymphedema has never been reported as a complication of breast carcinoma therapy. They report here the first case of a radiation-induced constrictive pericarditis revealed by severe lower limbs lymphedema. A 60-year-old woman was treated for left breast carcinoma with quadrantectomy, axillary lymphadenectomy, and combined radio chemotherapy (60 grays). Three and a half years later she suffered from a diffuse and increasing lower limbs lymphedema, which became huge and disabling. Radiation-induced constrictive pericarditis was evidenced by right cardiac cavities catheterization. A dramatic improvement was rapidly obtained after pericardectomy. Histopathologic analysis of the pericardium did not reveal neoplastic cells. Radiation-induced constrictive pericarditis is usually responsible for lower limbs edema, but lymphedema is exceptional. This case highlights the need to search for a constrictive pericarditis also in the case of lower limbs lymphedema, particularly in a patient treated with mediastinal radiotherapy or combined radio chemotherapy.

Painful jaundice revealing Kawasaki disease in a young man.

Liver involvement is usually a minor manifestation of Kawasaki disease and includes hepatobiliary dysfunction or gallbladder hydrops. We describe here an unusual case of jaundice revealing an adult onset Kawasaki disease. An 18-year-old man presented with abdominal pain and jaundice associated with cholestasis as the initial manifestation of Kawasaki disease. Abdominal evaluation (ultrasonography and CT-scan) did not find abnormality. Other signs typical of the Kawasaki disease occurred a few days later and permitted diagnosis. With aspirin and intravenous immunoglobulins, outcome was favorable without any cardiovascular complication. Our case suggests that Kawasaki disease should be added to the etiological list of painful febrile icterus in young patients.

Severe relapsing polychondritis occurring after ear piercing.

We describe a case of relapsing polychondritis with laryngo-tracheal involvement, occurring after ear piercing in a 39-year-old woman. Polychondritis was clearly time-related to ear piercing. This association draws attention to the risk of relapsing polychondritis during body art practices with cartilage trauma.