Deterioration of Bone Quality by Streptozotocin (STZ)-Induced Type 2 Diabetes Mellitus in Rats

Patients with diabetes mellitus (DM) have various skeletal disorders and bone quality can be impaired in DM leading to fractures. Wistar albino male rats (270?C300?g; n?=?16) were assigned randomly to nondiabetic and diabetic rats (single dose intravenous injection of 45?mg/kg streptozotocin). All rats in each group were perpetuated for 8?weeks, and blood glucose levels as well as body weights were measured once weekly. Biomechanical measurements were performed at the mid-diaphysis of the left femur with tensile test. Extrinsic and intrinsic properties were measured or calculated. Bone mineral density (BMD) was also evaluated and measured by dual-energy X-ray absorptiometry. Cross-sectional area of the femoral shaft was evaluated by computerized tomography. Blood glucose levels in diabetic rats were significantly increased compared to that of the nondiabetic rats, while the body and femur weights were decreased (P?<?0.05). In respect to the BMD, cross-sectional area and femur length, there were no statistically significant differences between the nondiabetic and diabetic rats (P?>?0.05). The maximum load, ultimate stress, and toughness endpoints in diabetic rats were significantly decreased compared to that of the nondiabetics (P?<?0.05). There were no statistically significant differences between the nondiabetic and diabetic rats with regard to the displacement and stiffness (P?>?0.05). Femurs of diabetic rats had less absorbed energy than that in nondiabetics (P?<?0.05). Ultimate strain was lower in diabetic rats than that in nondiabetics, while the elastic modulus was higher (P?>?0.05). The bone quality of rats is decreased by streptozotocin-induced type 2 diabetes mellitus.     

Investigations of Hg(II) and Pb(II) tolerance,removal and bioaccumulation and their effects on antioxidant enzymes on thermophilic Exiguobacterium profundum

Abstract

Hg(II) and Pb(II) tolerance, removal, bioaccumulation and effects on antioxidant enzymes of thermophilic Exiguobacterium profundum were investigated. The results indicated that Hg(II) was more toxic than Pb(II) to E. profundum. E. profundum was also more tolerant in solid medium than in liquid medium for Pb(II) and Hg(II). The bacterial growth was not significantly influenced at 1.0 and 2.5?mg/L Pb(II) and Hg(II) for 24?h. The highest Hg(II) and Pb(II) bioaccumulation amounts were determined as 37.56 and 54.35?mg metal/dried bacteria, respectively. Bioaccumulation capacities of the cell membrane of E. profundum for Hg(II) and Pb(II) were determined. The different concentrations of Pb(II) and Hg(II) enhanced the SOD and CAT enzymes. In addition, variations of the surface macrostructure and the functionality of E. profundum after the interaction with Hg(II) and Pb(II) were investigated by the scanning electron microscope (SEM) and the Fourier transform infrared spectroscopy (FT-IR), respectively.

This investigation obviously showed that thermophilic E. profundum can also be applied for removal and recovery of toxic metals from industrial wastewater. Clearly, a further investigation should be utilized by thermophilic microorganisms. According to antioxidant enyzme activities, E. profundum can be also used as a bioindicator for the detection of toxic metal pollution in natural water samples.     

The pharmacology of SDZ EAA 494, a competitive NMDA antagonist

SDZ EAA 494 ( -CPPene) was characterized as a competitive NMDA antagonist, having a pA₂ value against NMDA depolarizations in frog spinal cord and rat neocortex of 6.7–6.8 and a pK_i of 7.5 in a [³H]CGP39653 binding assay, with no action on other receptors or amine reuptake. The compound was orally active in rodent maximal electroshock models with an ED₅₀ of around 16 mg/kg, was protective in rats even 24 hours after oral application and had an oral therapeutic index of around 8. Muscle relaxation, ataxia, flattened body posture and reduced acquisition of a passive avoidance task, suggesting potential effects on memory formation, occurred at supra-anticonvulsant doses in rodents, with PCP-like stimulatory effects produced only by high i.p. doses or constant i.v. infusions. This favourable profile is discussed in relation to the negative outcome of a recent trial of the compound in patients with intractable epilepsy. The conclusion is drawn that standard models for screening new anticonvulsants are inappropriate to seeking drugs active in patients with a protracted convulsive history. The anti-ischaemic action of SDZ EAA 494 encourages further testing in brain trauma, in which the anticonvulsant action of the compound may be an added benefit.     

Predictors of Hypothyroidism Following Empirical Dose Radioiodine in Toxic Thyroid Nodules: Real-Life Experience

ObjectiveWe aimed to determine the factors predicting hypothyroidism after radioactive iodine (RAI) treatment in patients with toxic adenoma and toxic multinodular goiter.MethodsWe retrospectively collected the data of 237 patients with toxic multinodular goiter or toxic adenoma who had consecutively received RAI treatment between 2014 and 2020 at 2 medical centers. Patients who received the second RAI treatment and whose medical records could not be accessed were excluded from the study. Finally, 133 patients were included in the study. RAI was administered at an empirical dose of 15 or 20 mCi.ResultsThe median age of the 133 participants was 69 years (interquartile range, 62-75 years), and 64.7% of the participants were women. A total of 42.1% of the patients had toxic adenoma, whereas 57.9% of patients had toxic multinodular goiter. The median follow-up was 24 months (interquartile range, 11-38 months). During the follow-up, 61.7% of patients became euthyroid, 30.8% developed hypothyroidism, and 7.5% remained hyperthyroid. The median month of hypothyroidism onset was 4 months (interquartile range, 2-9 months). Regression analysis revealed 2 factors that could predict hypothyroidism: thyroid-stimulating hormone (odds ratio, 2.548; 95% CI, 1.042-6.231; P = .04) and thyroid volume (odds ratio, 0.930; 95% CI, 0.885-0.978; P = .005).ConclusionOverall, 30.8% of the cases developed hypothyroidism after the RAI treatment. Approximately 78% of hypothyroidism developed within the first 10 months. The risk of hypothyroidism was higher in patients with higher thyroid-stimulating hormone and smaller thyroid volume.