Browse

1 - 10 of 281 items :

  • Basic Medical Science, other x
  • Life Sciences x
Clear All
The bone hormones and their potential effects on glucose and energy metabolism

Abstract

The bones form the framework of our body. We know that bones protect our vital organs, regulate calcium and phosphorous homeostasis, and function as a site of erythropoiesis. More recently, however, the identification of bone hormones has allowed us to envision bones as endocrine organs too. Within the last few years, the bone hormones osteocalcin and lipocalin 2 have been implicated with glucose and energy metabolism. We systematically reviewed articles surrounding this subject and found a clear relationship between the osteocalcin levels and glucose tolerance and insulin sensitivity. We also found that many journals have shown the detrimental effects of an absences of lipocalin 2 from adipocytes. As osteocalcin administration to mice showed decreased blood glucose levels and promoted glucose tolerance and insulin sensitivity. Future studies could perhaps explore the use of osteocalcin as a supplement for type 2 diabetes.

Open access
Characterization of a Novel Avian Avulavirus 1 of Class I isolated from a Mute Swan (Cygnus Olor) in Macedonia in 2012

Abstract

Avian avulavirus type 1 (AAvV-1) belongs to the family Paramyxoviridae, genus Avulavirus. Even though belonging to a single serotype, there is great genetic variability between these viruses. On the basis of the available complete fusion (F) gene and whole genome sequences and using the genotype classification system, AAvV-1 viruses are divided in two major groups: class I and class II. Class I viruses are predominantly avirulent viruses and majority of the isolations come from waterfowl and domestic poultry from live bird markets in USA and China although isolations from wild birds are reported globally. In our study we used classical, molecular and phylogenetic tools to characterize an AAvV-1 isolated from a mute swan in Macedonia. Based on the complete F gene sequence, we have concluded that the virus designated as AAvV-1/mute swan/Macedonia/546/2012 (KP123431) belongs to the class I of AAvV-1 with an avirulent cleavage site motif 112ERQER*L117. The virus could not be assigned to any of the four currently existing subgenotypes (1a, 1b, 1c or 1d) of the single genotype 1 of class I viruses. Two distant viruses, isolated from goose in Alaska in 1991 and from goose in Ohio in 1987, shared the highest nucleotide sequence identity of the complete F gene with the isolate in our study: 92.7% and 92.8%, respectively. This is the first report of isolation of class I AAvV-1 in Southeastern Europe. The asymptomatic nature and the underreporting of sequences from the class I viruses impede the understanding of the molecular epidemiology and evolution of this group of viruses.

Open access
The coexistence of infundibular pituicytoma and Cushing’s disease due to pituitary adenoma: A case report

Abstract

Objectives. Pituicytomas are rare, solid, well-circumscribed, low grade (grade I), non-neuroendocrine, and noninfiltrative tumors of the neurohypophysis or infundibulum, which appear in the sellar/suprasellar regions. Herein, we present a case with Cushing’s disease (CD) caused by an ACTH-secreting pituitary adenoma in association with an infundibular pituicytoma.

Subject and Results. A 37-year-old male patient presented to the hospital with a six-month history of blurry vision. Physical examination demonstrated plethora, excessive sweating, weight gain, moon facies, and acne. Basal serum cortisol and ACTH levels were 16 µg/dl and 32 pg/ml, respectively. The results of screening tests were suggestive of Cushing syndrome. It was also 1.97 µg/dl following 8 mg dexamethasone suppression test which was consistent with CD. Pituitary MR imaging revealed a single lesion measuring 6x6.5 mm on the pituitary stalk. Infundibular mass excision and pituitary exploration by extended endoscopic endonasal approach were applied. On immunohistochemistry, strong diffuse immunolabeling for both S100 and TTF-1 was noted for the cells of infundibular mass, diagnosed as pituicytoma. Because the developed panhypopituitarism postoperatively, patient was discharged with daily desmopressin, levothyroxine, hydrocortisone, and intramuscular testosterone, once a month.

Conclusions. Pituicytoma is an uncommon noninvasive tumor of the sellar and suprasellar regions. In this case report, we described a patient with Cushing’s disease to whom MRI displayed only an infundibular well-circumscribed lesion, but not any pituitary adenoma. Despite the absence of any sellar lesion, awareness of other undetected possible lesion and exploring hypophysis during the transsphenoidal surgery is mandatory for the correct diagnosis.

Open access
Comparing the preventive effect of sodium hydrosulfide, leptin, and curcumin against L-arginine induced acute pancreatitis in rats: role of corticosterone and inducible nitric oxide synthase

Abstract

Objectives. Acute pancreatitis (AP) is a life-threatening condition. Using antioxidants in AP is insufficient and conflicting. Therefore, this study compared the effect of hydrogen sulfide (H2S) donor, sodium hydrosulfide (NaHS), leptin or curcumin pretreatment on AP induced by L-arginine.

Methods. Forty adult male rats were used and classified into: 1) control; 2) AP group [each rat was intraperitoneally (i.p.) injected with 2 doses of L-arginine of 250 mg/100 g body weight (b.w.) with an interval of 1 h]; 3) NaHS+AP group (each rat was i.p. injected with 10 mg/kg b.w. of NaHS 1 h before induction of AP); 4) leptin+AP group (each rat was pretreated with 10 μg/kg b.w. of leptin 30 min before induction of AP; and 5) curcumin+AP group (in which rats were i.p. injected with 150 mg/kg b.w. of curcumin 30 min before induction of AP). Serum amylase, lipase, nitric oxide (NO), tumor necrosis factor alpha (TNF-α), and corticosterone (CORT) levels were assayed. In addition, pancreatic tissues were obtained for histopathological examination and malondialde-hyde (MDA), total antioxidant capacity (TAC), and inducible nitric oxide synthase (iNOS) levels were measured.

Results. All AP treated groups showed significant decrease in serum levels of pancreatic enzymes, NO, and TNF-α, and pancreatic MDA and iNOS levels, while TAC levels were significantly increased. NaHS caused more limitation of inflammation than leptin and curcumin by affecting iNOS. Leptin was more potent than curcumin due to the stimulatory effect of leptin on glucocorticoid release to counteract inflammation.

Conclusions. NaHS was more effective in AP amelioration than the leptin and curcumin.

Open access
Comparison of the Chemical Composition of Whey Cheeses: Urda And Ricotta

Abstract

This study was conducted to evaluate the nutritional quality of two types of cheese prepared from bovine whey: Urda and Ricotta. Cheeses were examined for chemical parameters and their amino acids profile was determined. The results revealed that the chemical composition of the observed whey cheeses was highly significantly different (p<0.01) from each other. The amounts of dry matter, fat, protein, lactose, ash and salt were higher in Ricotta compared with Urda cheese samples. On the other hand, Urda contained more moisture, fat on a dry matter basis and moisture on a fat-free basis (79.59%, 27.50%, 84.27% versus 69.82%, 21.02%, 74.56%, respectively). Especially higher yield, salt in moisture content and energy values were observed in Ricotta cheese (5.93%, 3.12%, 145.99Kcal/100g versus 4.39%, 2.40%, 108.97Kcal/100g; Ricotta and Urda, respectively). Whey cheeses are a particularly good source of amino acids containing approximately - Ricotta: leucine (1.60g/100g), lysine (1.17g/100g), phenylalanine (0.78g/100g) and followed by threonine (0.77g/100g), while Urda contained leucine (0.80g/100g), lysine (0.45g/100g), threonine (0.68g/100g) and phenylalanine (0.31g/100g). Both cheese varieties contained glutamic and aspartic acid as the predominant non-essential amino acids (Ricotta: 3.91g/100g and 1.68g/100g versus Urda: 1.65g/100g and 0.80g/100g, respectively). Generally, from a nutritional point of view, the investigated whey cheeses could be considered as cheeses with low salt and fat content, as well as cheeses particularly abundant in branched chain amino acids (leucine, isoleucine and valine). These results also emphasize their advantages as products that present a cost-effective way of dealing with whey as waste material.

Open access
Determination of Free Doxycycline Concentrations in the Plasma and Milk of Sheep and in the Plasma of Rabbits by using the HPLC Method

Abstract

A fast and sensitive HPLC method was validated in order to analyze doxycycline in plasma and milk of sheep and in plasma of rabbits. The samples were processed with trifluoroacetic acid (TFA). After the centrifugation step, a supernatant containing extracted doxycycline and internal standard oxytetracycline was injected into the HPLC system with PDA detection. The method showed linearity in the range of 0.125 - 2.5 µg/mL for ovine plasma, 0.125 – 5.0 µg/mL for ovine milk, and 0.125 – 1 µg/mL for rabbit plasma. The inter-assay precision varied between 5.69 – 13.55 %. Values for intra-assay precision were between 0.62 – 8.67 %. Accuracy was higher than 90% in all of the tested concentrations in the three types of biological matrices. The mean extraction recovery was higher than 90 % for all matrices. In order to handle only with free drug concentrations, microfiltration of standard solutions with low (0.25mg/mL), medium (0.5mg/mL) and high (1.0mg/mL) concentration was performed. A percentage for correction of the quantified doxycycline was calculated. The most significant adjustments should be made at the low concentrations. The correction for rabbit plasma is 24.63±5.03%, for ovine plasma is 20.10±8.01% and for milk–16.68±0.04 %. This method can be used for routine determination of doxycycline concentrations for pharmacokinetic studies and further dosage adjustment.

Open access
Early postnatal hypothalamic-pituitary-adrenal axis activity and reduced insulin sensitivity in adult rats

Abstract

Objective. Early life stress influences the development of metabolic disorders, including functional changes in the developing of pancreas mediated hypothalamic-pituitary-adrenal (HPA) axis. In the present study, the role of an early postnatal stress on corticosterone, glucose, and insulin levels was investigated during young adulthood.

Methods. Two groups of pups were studied, including control group (pups not receiving foot shock by communication box), and early stress group (pups receiving foot shock by communication box 2 times/day for 5 consecutive days). In rats, concentration of plasma corticosterone, glucose, and insulin was detected before and after placing them into the communication box at 2 weeks of age. At 8–10 weeks of age, concentrations of plasma corticosterone, glucose, and insulin and glucose tolerance were measured in young adult rats.

Results. Our results showed that early postnatal foot shock stress increased the corticosterone, insulin, and glucose levels in the postnatal age (p<0.01) that did not last until young adult age, but it caused a significant increase in plasma glucose and insulin levels (p<0.05) following the intraperitoneal glucose tolerance test (IPGTT) in young adult rats.

Conclusions. These results suggest that impaired IPGTT in young adult rats who experienced early postnatal stress can indicate insulin resistance or reduced insulin sensitivity that make it at risk of the type 2 diabetes later in life.

Open access
The Effect of Diet Supplemented with Dandelion’s (Taraxacum Officinale) Extract on the Productive and Blood Parameters of Common Carp (Cyprinus Carpio L.), Cultivated in the Recirculation System

Abstract

The aim of the current study was to test the effect of a diet supplemented with dandelion’s (Taraxacum officinale) extract on the productive traits and blood parameters in common carp (Cyprinus carpio L.) cultivated in an recirculation aquaculture system. The carps were cultivated at a stocking density of 7.2 kg/m3 in recirculation aquaculture system. The fish were split into the following two experimental groups: DF (the fish were fed with feed supplemented with dandelion’s extract) and CF (the fish were fed with feed without supplementation). Common carp fed with a diet added with dandelion’s extract at a quantity of 0.8% from daily feed ratio, did not affect the hydrochemical parameters (pH, dissolved oxygen, and electrical conductivity). The carps fed with feed supplemented with dandelion’s extract did not show better productive traits compared with these found for carp from the control variant. The carp from experimental groups had a higher survival rate, final weight, average individual weight gain and specific growth rate (SGR), respectively with 13.2%, 3.94%, 31.5% and 31.3%, compared with the average values of these parameters measured in individuals fed with the control feed, but the differences were not statistically significant (P≥0.05). Supplementation of feed with dandelion’s extract significantly decreased the plasma cholesterol (4.76%) and triglyceride (61.2%) content, promoting hypolipidemic status in fish (P≤0.05).

Open access
Effect of glucose deprivation on the expression of genes encoding glucocorticoid receptor and some related factors in ERN1-knockdown U87 glioma cells

Abstract

Objective. The aim of the present study was to examine the effect of glucose deprivation on the expression of genes encoded glucocorticoid receptor (NR3C1) and some related proteins (NR3C2, AHR, NRIP1, NNT, ARHGAP35, SGK1, and SGK3) in U87 glioma cells in response to inhibition of endoplasmic reticulum stress signaling mediated by ERN1/IRE1 (endoplasmic reticulum to nucleus signaling 1/inositol requiring enzyme 1) for evaluation of their possible significance in the control of glioma growth through endoplasmic reticulum stress signaling mediated by IRE1 and glucose deprivation.

Methods. The expression of NR3C1, NR3C2, AHR, NRIP1, NNT, ARHGAP35, SGK1, and SGK3 genes in U87 glioma cells transfected by empty vector pcDNA3.1 (control cells) and cells without ERN1 signaling enzyme function (transfected by dnERN1) under glucose deprivation was studied by real time quantitative polymerase chain reaction.

Results. It was shown that the expression level of NR3C2, AHR, SGK1, SGK3, and NNT genes was up-regulated in control U87 glioma cells under glucose deprivation condition in comparison with the control cells growing with glucose. At the same time, the expression of NRIP1 gene is down-regulated in these glioma cells under glucose deprivation, but NR3C1 and ARHGAP35 genes was resistant to this experimental condition. We also showed that inhibition of ERN1 signaling enzyme function significantly modified the response of most studied gene expressions to glucose deprivation condition. Thus, effect of glucose deprivation on the expression level of NR3C2, AHR, and SGK1 genes was significantly stronger in ERN1 knockdown U87 glioma cells since the expression of NNT gene was resistant to glucose deprivation condition. Moreover, the inhibition of ERN1 enzymatic activities in U87 glioma cells led to up-regulation of ARHGAP35 gene expression and significant down-regulation of the expression of SGK3 gene in response to glucose deprivation condition.

Conclusions. Results of this study demonstrated that glucose deprivation did not change the expression level of NR3C1 gene but it significantly affected the expression of NR3C2, AHR, NRIP, SGK1, SGK3, and NNT genes in vector-transfected U87 glioma cells in gene specific manner and possibly contributed to the control of glioma growth since the expression of most studied genes in glucose deprivation condition was significantly dependent on the functional activity of IRE1 signaling enzyme.

Open access
Effect of letrozole on spermogram parameters and hormonal profile in infertile men: A clinical trial study

Abstract

Objective. There is no reliable treatment for men with idiopathic infertility, but the relationship between severe sperm production and the ratio of estrogen to testosterone levels has been shown. Aromatase is an enzyme that plays an important role in converting testosterone to estradiol and androstenedione to estrogen. Aromatase inhibitors can increase testosterone and androgen production without increasing the amount of estrogen in circulation. The aim of this study was to evaluate the effect of aromatase inhibitor letrozole on the male infertility.

Method. This pre- and post-quasi-experimental clinical trial was carried out on 41 men with an infertility diagnosis. The basic hormonal profile included FSH, LH, testosterone, and estradiol. The ratio of testosterone to serum estradiol was also calculated and recorded. The sperm analysis was performed before the treatment and the seminal parameters were evaluated and recorded. Patients were then treated with letrozole 2.5 mg daily for 4 months. At the end of 4th months, the hormonal profile was studied and seminal analysis performed and recorded.

Results. The levels of FSH, LH, testosterone, and estradiol, and the ratio of testosterone to estradiol increased significantly after letrozole treatment. The sperm concentration, sperm motility, and sperm forward motion significantly increased after letrozole treatment. Sperm morphology only lightly altered.

Conclusion. The ratio of testosterone to estradiol levels in infertile men treated with aromatase inhibitor improved and caused changes in sperm parameters. Letrozole may be used to improve sperm parameters in infertile men with low serum testosterone to estradiol ratio.

Open access