СТРУКТУРНІ ВІДМІННОСТІ В ПАРАЩИТОПОДІБНИХ ЗАЛОЗАХ ЩУРІВ РІЗНОГО ВІКУ З МОДЕЛЬОВАНИМ АЛІМЕНТАРНИМ ОЖИРІННЯМ

Background. Recently, the prevalence of obesity has been increasing rapidly, reaching pandemic proportions. The causes of obesity are primarily lifestyle and malnutrition, mainly excessive calorie intake. There is still no consensus on the specifics of the influence of visceral obesity on histomorphological changes in white adipose tissue in animals of different ages. The aim of the work was to compare morphological changes in white adipose tissue in rats of different ages with visceral obesity. Materials and methods. The study was conducted on male Wistar rat’s line, aged 6 and 21 months. Visceral obesity in animals was modeled by keeping them on a high-calorie diet (580 kcal / 100 g) for 12 weeks, with an excess of fats and carbohydrates. Control animals were on a standard diet (330 kcal / 100 g). Histological preparations were prepared from the white adipose tissue using standard methods. Histomorphometry was performed using the computer program "ImageJ". Results. It was found that in the white adipose tissue of rats (regardless of their age) that received a high-calorie diet, an increase in the size of adipocytes occurs due to the accumulation of triglycerides in them. However, in young experimental rats, the number of adipocytes with a diameter of >100 μm was 10 times greater than in old animals. This indicates a hypertrophic type of obesity, and a more intense accumulation of lipids in adipocytes occurs at a young age. In addition, in the white adipose tissue of 6 month-old experimental rats, an increase in connective tissue was noted. While in 21 month-old animals, the amount of connective tissue, on the contrary, decreased. A decrease in white adipose tissue vascularization was observed in both experimental groups of rats. Conclusions. The intensity of morphological changes in the white adipose tissue depended on the degree of obesity and the age of the animals. In young rats, these changes were more pronounced than in older animals. These data are of interest for practical medicine in the development of new effective methods for the prevention and treatment of visceral obesity in patients of different ages.

BACKGROUND: The problem of diagnosis, treatment and prevention of fat liver disease (FLD) is one of the actual problems of modern medicine. In this regard, the need for the creation of reliable experimental models of the FLD, which would be as close as possible to the pathogenetic patterns of the development of this disease in humans.AIM: To create an experimental model of FLD and compare the efficiency of its reproduction in rats of different ages.MATERIALS AND METHODS: The study was conducted on male Wistar rats, whose ages at the beginning of the experiment were 3 and 18 months. Control animals were fed a standard diet. The experimental rats were kept on a diet with excess fat (45 %) and carbohydrates (31 %) for 12 weeks. The liver tissue samples were taken for morphological studies of FLD. Histological preparations were made according to the standard technique. Morphometry on digital images of micropreparations was conducted using the computer program «IMAGE J». The concentration of lipids, cholesterol, and triglecerides in the liver tissue was determined, and the concentration of ALT in the blood serum was determined. To assess the biophysical properties of the liver tissue, the method of multifrequency bioimpedance measurement was used.RESULTS: The transfer of animals to a high-calorie diet developed by us led to the development of FLD. This was evidenced by an increase of the liver mass, its pale shade and soft consistency. Morphometric signs of FLD were also revealed. Hypertrophy of hepatocytes was observed with a simultaneous decrease in the nuclear-cytoplasmic ratio; accumulation of numerous lipid inclusions in the cytoplasm and the appearance of large lipid droplets replacing the voids of dead hepatocytes. The number of binuclear hepatocytes and nucleolus in the nucleus, the relative area of the sinusoid network were decreased. An increase in the concentration of lipids, cholesterol and triglecerides in the liver tissue of experimental rats, as well as the activity of ALT in the blood serum, was observed. Changes in the bioimpedance measurements of the liver tissue also indicated the development of severe fatty degeneration of the liver in both young (to a greater extent) and old rats.CONCLUSION: The model of FLD we have advanced based on a combined (fat-carbohydrate) high-calorie diet. It leads to the development of pronounced morphological, biochemical and biophysical signs of this pathology in all experimental rats. The most pronounced manifestations of FLD are observed in young animals.

The aim of the study was to compare histomorphological disorders of the thyroid gland in rats of different ages with alimentary-induced obesity. The study was carried out on male Wistar rats, aged six and 21 months. Alimentary obesity in animals was modelled by keeping them on a high-calorie diet (580 kcal 100 g‑1) for 12 weeks, with an excess content of fats and carbohydrates. Control animals were given a standard diet (330 kcal 100 g‑1). Histological preparations were made from thyroid tissue. Histomorphometry was carried out using the computer program “ImageJ”. It was revealed that a 3‑month high-calorie diet led to the appearance of pronounced histomorphological signs of thyroid hypofunction in rats. Intensive colloid resorption and a decrease in colloid area occurred in the gland. Devastated follicles were common. Thyrocytes acquired a prismatic shape. There was hyperplasia of the thyroid gland, which led to an increase in its size. The intensity of morphological disorders of the thyroid gland depended on the degree of obesity and had a distinct age-dependent character. In young rats, these changes were more pronounced than in older animals.

Fluorescence-Guided Minimally Invasive Parathyroidectomy: A Novel Surgical Therapy for Secondary Hyperparathyroidism

Background. Literature data on the effect of methionine on functional activity and, especially, on morphological changes in the thyroid gland are sporadic. This may be due to a number of reasons, such as: different ages of experimental animals; different dosage of methionine; different seasonality and duration of experiments.
 Aims: To investigate the morphological changes in the thyroid gland of rats of different ages after methionine administration.
 Material and methods. The experiments were performed on 48 Wistar male rats of 3 and 15 months of age. Experimental animals received methionine daily for 21 days at a dose of 250 mg / kg of body weight in addition to the standard diet. Histological preparations were made from the thyroid tissue according to the standard method. The gland morphometry was performed on digital images using the computer program Image J.
 Results. It was found that 21-day administration of methionine to rats of both 3 and 15 months of age led to a decrease in the cross-sectional area of the follicles and colloid, the accumulation index of colloid and the relative area of the conective tissue in the thyroid gland. But the follicular-colloid index, the number of resorption vacuoles in the colloid, and the number of interfollicular islets were increased. Morphological changes in the thyroid gland of 15-month-old experimental rats were manifested to a greater extent than in young animals.
 Conclusions. Thus, the influence of methionine increases the histomorphological signs of the synthetic activity of the thyroid gland in rats of different ages.

The aim of the work was to study the morphological changes in the rat’s liver of different ages after prolonged administration of magnesium chloride. The experiments were performed on 48 Wistar male rats at 3 and 15 months of age. Experi mental animals, in addition to the standard diet, received magnesium chloride daily for 21 days at a dose of 50 mg / kg of body weight. Histological preparations were made from the liver tissue according to the standard method. The liver morphometry was performed on digital images using the computer program Image J. The content of magnesium cations was determined in the serum and suspension of red blood cells. Based on the results of our studies, it can be assumed that the administration of magnesium chloride activates the processes of physiological regeneration and functional activity of the liver parenchyma in rats of different ages. This is evidenced by an increase in the number of binuclear cells and nucleolus in the nucleus of hepatocytes, an increase in the nuclear-cytoplasmic and nucleolar-nuclear ratio. The relative area of the sinusoid network, the number and density of connective tissue cells were increased in the liver of 3-month-old experimental rats. This may indicate an increase of trophic and protective activity of the stroma in this organ. Experimental rats (15-month-old animals) revealed a moderate increasing in the erythrocyte suspension and blood serum magnesium content. The administration of magnesium chloride has the morphological features indicating an increasing of the physiological regeneration and activity of the liver parenchyma in young (to a greater extent) and adult animals.

When performing parathyroid or thyroid surgery, surgeons must distinguish parathyroid tissue from the surrounding thyroid tissue, to preserve healthy parathyroid tissue while excising diseased thyroid tissue or to completely remove pathological parathyroid lesions. Here, we explored the feasibility of labeling the parathyroid glands for easy identification by administering 5-aminolevulinic acid (5-ALA) orally to patients undergoing endocrine neck surgery, because 5-ALA accumulates in the parathyroid and has a fluorescent metabolite, protoporphyrin IX. Twenty-nine patients about to undergo endocrine (parathyroid or thyroid gland) neck surgery were orally given 5-ALA, a nontoxic substance that occurs naturally in the human body and has no known major side effects. During surgery, we used blue light to excite protoporphyrin IX, the fluorescent metabolite of 5-ALA, and viewed the resulting bright red fluorescence through an optical filter. In the majority of the patients, the parathyroid glands were defined by a clear fluorescence. In 23 patients with pathological parathyroid tissue, the fluorescence enabled us to identify and completely remove diseased parathyroid tissue. In 3 patients with thyroid disease, we were able to easily remove diseased thyroid tissue, and an accidentally removed parathyroid gland was autotransplanted during surgery. In all but a few cases, 5-ALA clearly labeled parathyroid tissue, allowing for its clean removal or preservation according to the purpose of the surgery. This simple, benign technique is extremely useful for identifying parathyroid tissue, whether pathological or normal, during endocrine neck surgery.

Successful Detection and Removal of a Functional Parathyroid Adenoma in a Pony Using Technetium Tc 99m Sestamibi Scintigraphy

Influence of parathyroid mass on the regulation of PTH secretion

Minimally Invasive Resection for Mediastinal Ectopic Parathyroid Glands

In the United States thyroidectomy is a frequently performed surgery by both general and head and neck surgeons. Even the most experienced thyroid surgeon, however, has probably received a pathology report stating that an incidental parathyroid gland or parathyroid tissue was found in the submitted thyroidectomy specimen. The aim of this report is to explore some of the pathologic and clinical characteristics of unintentional parathyroidectomy during thyroidectomy. A retrospective review was performed of thyroidectomies performed at the University of California, Los Angeles, Center for the Health Sciences between 1989 and June 1998 which had pathology reports showing parathyroid tissue contained within the thyroidectomy specimen. This excluded any tissue submitted separately to be evaluated for parathyroid tissue and parathyroid tissue removed unintentionally during a thyroidectomy for a different procedure such as a laryngectomy or surgery for parathyroid disease. The pathology slides were reviewed to determine the incidence of unintentional parathyroid tissue removal, the size of the parathyroid tissue found within the thyroid specimen, the location of the parathyroid tissue (extracapsular, intracapsular, intrathyroidal), and whether this unintentional parathyroidectomy during thyroidectomy caused clinical consequences. Four hundred fourteen applicable thyroidectomies were performed during this time with 45 (11%) discovered cases of unintentional parathyroidectomy during thyroidectomy. Twenty-five (56%) cases were discovered during thyroidectomy for benign disease, and 20 (44%) during thyroidectomy for malignant thyroid disease. All the parathyroid tissue was normal and was found in extracapsular (58%), intracapsular (20%), or intrathyroidal (22%) locations. Of these 45 cases, recurrent laryngeal nerve paralysis was found only in two patients who had the nerve resected intentionally during the thyroidectomy, and none of the patients developed permanent hypocalcemia. Incidental parathyroid gland tissue was reported in 11% of the thyroidectomies performed in our series, without the clinical consequence of hypocalcemia. The majority (78%) of this parathyroid tissue was found in the extracapsular and intracapsular locations; therefore it is possible that these parathyroid glands may be identified and preserved with more meticulous inspection of the thyroid capsule during and after thyroidectomy to decrease the incidence of unintentional parathyroidectomy during thyroidectomy in the future.

Histomorphological changes of visceral white adipose tissue in obesity as a function of the level of energy metabolism in the body have not been sufficiently studied. The aim of this study was to investigate and compare the structural changes of visceral white adipose tissue in rats with different metabolic levels and severe visceral obesity. The study was carried out on male Wistar rats aged 3 months at the start of the experiment. Control animals received standard diet. Experimental rats were fed a high calorie diet for 12 weeks. At the end of the experiment, rats from both the control and experimental groups were divided into low and high level of energy metabolism depending on the intensity of total oxygen consumption. Histological preparations of visceral white adipose tissue were prepared according to the standard method. Histomorphometry was performed on digital images using the “Image J 1.34p” computer program. Biochemical methods were used to determine the concentration of triglycerides, lipids and cholesterol in blood serum. The method of multifrequency bioimpedance was used to assess the biophysical properties of visceral white adipose tissue. The data obtained were processed by methods of variational statistics using one-way analysis of variance. It was shown that long-term use of a high-calorie diet led to the development of visceral obesity, which was manifested by a significant increase in the weight of visceral fat and an increase in the concentration of indicators of lipid metabolism in blood serum. It was found that a high-calorie diet altered the morphological structure of the rat’s visceral white adipose tissue, leading to adipocyte hypertrophy, reduced blood volume and increased the amount of connective tissue in it. The bioelectrical properties of the visceral white adipose tissue changed, as evidenced by an increase in its electrical impedance and a decrease in its frequency dispersion coefficient. The intensity of structural, biochemical and biophysical changes in the visceral white adipose tissue was more pronounced in rats with low level of energy metabolism and depended on the degree of obesity. The results obtained are important for practical medicine in the development of new effective methods for the prevention and treatment of obesity in patients according to level of energy metabolism.

Association of decreased calcium-sensing receptor expression with proliferation of parathyroid cells in secondary hyperparathyroidism

The Cytoscan model E-II in intraoperative parathyroid gland identification in a rabbit model

Effects of different type of parathyroid damage to the postoperative functional recovery of parathyroid during thyroid operation