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Abstract  

The glenohumeral joint is not a classical mass bearing joint, the treatment of primary osteoarthritis is conservative. In all other cases, when the arthritis is associated with unbalance of the soft tissues, the treatment solution of this pathology is arthroplasty. The purpose of this study was to examine the altered metabolism in human degenerated cartilage of the shoulder joint. With the rise of temperature an endothermic reaction was observed in all cases. The use differential scanning calorimetry as part of thermal analysis was a reliable method for differentiating normal hyaline cartilage from degenerated samples.

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Abstract  

The purpose of this study was to further characterize the altered metabolism spondylolisthesis that promotes disease progression. Degenerative human cartilage (intervertebral disc, facet joint and vertebral end-plate) was obtained during 15 posterior lumbar spine interbody fusion procedures performed at the University of Szeged. The thermal properties of samples were determined by differential scanning calorimetry (Mettler-Toledo DSC 821e). Greatest change in the enthalpy was observed in the intervertebral disc samples: −1600.78 J g−1. Denaturation caused by heating in the normal human hyaline cartilage needed −1493.31 J g−1 energy. Characterization of the altered metabolism that promotes disease progression should lead to future treatment options.

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Abstract  

During recent years, knowledge of rheumatoid arthritis has increased, and management of the disease has improved. A limited number of papers have been published before on the subject of thermal analysis of degenerative cartilage but rheumatoid arthritis (RA) has not been studied previously. A new protocol had to be established before the investigation. The purpose of this study was to further characterize the altered metabolism in human RA cartilage that promotes disease progression. Previously, these methods have not been used for this purpose. The use of thermal analysis could be an effective method for controlling the relationship between biomarkers and disease progression.

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Abstract  

Shoulder pain is a common presentation of the dysfunction of the glenohumeral joint. The long head of the biceps tendon has been proposed as a source of pain in rotator cuff pathologies. The rotator cuff is a dynamic stabilizer of the glenohumeral joint, and its tear can create different shoulder dysfunctions. The long head of the biceps has a special intraarticular localisation, so the arthricular destruction affects its tendon too. In the process of the rotator cuff degeneration and tear the structure of the biceps tendon pathological transforms. With foregoing studies authors have demonstrated the feasibility of DSC in the investigation of the musculoskeletal system. The aim of this study was to establish the curves and the histological properties of the tendon of the long head of the biceps in different magnitudes of the rotator cuff tear on cadavers. The DSC results clearly proved that definitive differences are present between the structural state of the tendons in different magnitudes of the rotator cuff tears, which have also been demonstrated by the histological examination.

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Abstract  

Osteoarthritis, although classically conceived of as a degenerative consequence of aging, is a disease with an increasingly well-characterized molecular pathophysiology. Pathologic changes in cartilage composition and molecular organization, as well as elevated water content, alter the exquisite balance of biomechanical properties. Much of what is known about changes in the extracellular matrix in osteoarthritis comes from animal models. Previously, thermogravimetric methods have not been used for compositional thermoanalytical study of normal and degenerative human hyaline cartilage. For this reason the research group established a sufficient new thermogravimetric protocol, which proved water content elevation contributing to disease progression.

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Abstract  

A control system for monitoring the radioactive concentration in aqueous wastes of nuclear installations was elaborated. The mobile station developed for in situ control enables simultaneous measurement of gamma radiation in the energy range of 0.15–2.0 MeV and that of beta radiation in the energy range of 0.3–2.0 MeV by means of a combined scintillation detector. Disturbing effects of accompanying and secundary radiations on the determination of the counting efficiency vs. radiation energy functions used in calculation of the radioactive concentration limits as well as some experiences during a long time of operation of the system have been discussed.

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Abstract  

The purpose of this investigation was to further elucidate calorimetric properties of cartilage samples from femoral head necrosis and osteoarthritis from live surgeries. The natural course of this disease is one of steady progression with eventual collapse of the femoral head, followed by secondary osteoarthritis in the hip joint. All samples showed a clear denaturation peak on the calorimetric curve. Cartilage obtained from necrotic femoral head required the lowest amount of energy for decomposition. The use differential scanning calorimetry as part of thermal analysis was a reliable method for differentiating.

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Journal of Thermal Analysis and Calorimetry
Authors:
J. Bajdik
,
K. Pintye-Hódi
,
G. Regdon
,
P. Fazekas
,
P. Szabó-Révész
, and
I. Erős

Abstract  

Eudragit NE 30 D aqueous dispersion is a commonly used coating material, which contains methacrylate copolymers as film-forming agent and nonoxynol 100 as an endogenous emulsifier. The dissolution of the active ingredient from Eudragit NE-coated samples during storage is known to undergo a change. The crystallization of the emulsifier agent can play an important role in this. This polymer is not soluble in the gastrointestinal tract, but is permeable. Various parameters can influence the permeability of this film, e.g. via the tensile properties of the film. Change in the film thickness can cause the stretching of the film on a solid surface. Alterations in this physical parameter of the film were measured and the effects of different storage conditions were evaluated. The free film was prepared by spraying onto teflon. The crystallization of nonoxynol was followed via the changes in the DSC curve of the free film. A relationship was found between the film thickness and the crystallization of nonoxynol. It was established that the different storage conditions influence these changes. The temperature and the air humidity are important in this phenomenon. Lengthening of the storage time increased the difference in film thickness and crystallisation of emulsifier.

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Journal of Thermal Analysis and Calorimetry
Authors:
J. Bajdik
,
K. Pintye-Hódi
,
Cs. Novák
,
P. Szabó-Révész
,
G. Regdon
,
I. Erős
, and
G. Pokol

Abstract  

Dimenhydrinate is a heat-sensitive antihistamine with a low melting point. The heat-sensitive feature is of importance if direct compression is used. Direct measurement of the heat originating in the texture of tablets during compression is very difficult. Thermoanalytical methods were used as indirect methods to describe the changes in material properties at high temperature: differential scanning calorimetry, thermomicroscopy and thermogravimetric analysis. Film coating method is widely used in pharmaceutical technology. A fluidized bed apparatus was applied to coat the crystals. The coating film forming agent was hydroxy-propyl-methylcellulose (HPMC), which is a gastric-soluble polymer. Thermoanalytical measurements reveal that dimenhydrinate crystals are sensitive to heat. Film coating method does not alter the shape of the DSC curve of dimenhydrinate, but increases the melting point. The presence of a macromolecular film reduces the thermal conductivity, because it separates the particles.

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Journal of Thermal Analysis and Calorimetry
Authors:
Á. Beretzky
,
P. Kása
,
K. Pintye-Hódi
,
J. Bajdik
,
P. Szabó-Révész
, and
I. Erős

Abstract  

The flowability of needle- or plate-shaped crystals is very poor and the direct compression of these crystals is difficult. Commercial phenylbutazone consists of needle crystals and it has three polymorphs.The aim of this work was to investigate the solid-state thermal stability of phenylbutazone at condition of the pelletization process (40°C; 60 min). The other aim was the preparation of phenylbutazone pellets with centrifugal granulator.Based non the flowability and the other parameters of, the pellets, they are suitable for capsule filling or tabletting. The centrifugal granulation and the conditions were favourable for the preparation of pellets from phenylbutazone in the form of needle crystals.

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