Anatase titanium dioxide nanoparticles in mice: evidence for induced structural and functional sperm defects after short-, but not long-, term exposure

Titanium dioxide (TiO₂) nanoparticles (TNPs) are widely used commercially and exist in a variety of products. To determine if anatase TNPs (ATNPs) in doses smaller than previously used reach the scrotum after entry in the body at a distant location and induce sperm defects, 100% ATNP (2.5 or 5 mg kg⁻¹ body weight) was administered intraperitoneally to adult males for three consecutive days, followed by sacrifice 1, 2, 3, or 5 weeks later (long-) or 24, 48 or 120 h (short-term exposure). Transmission electron microscopy revealed the presence of ANTP in scrotal adipose tissues collected 120 h postinjection when cytokine evaluation showed an inflammatory response in epididymal tissues and fluid. At 120 h and up to 3 weeks postinjection, testicular histology revealed enlarged interstitial spaces. Significantly increased numbers of terminal deoxyribonucleotidyl transferase-mediated dUTP nick-end labeling-positive (apoptotic) germ (P = 0.002) and interstitial space cells (P = 0.04) were detected in treated males. Caudal epididymal sperm from the short-term, but not a long-term, arm showed significantly (P < 0.001) increased frequencies of flagellar abnormalities, excess residual cytoplasm (ERC), and unreacted acrosomes in treated versus controls (dose-response relationship). A novel correlation between ERC and unreacted acrosomes was uncovered. At 120 h, there were significant decreases in hyperactivated motility (P < 0.001) and mitochondrial membrane potential (P < 0.05), and increased reactive oxygen species levels (P < 0.00001) in treated versus control sperm. These results indicate that at 4–8 days postinjection, ANTP induce structural and functional sperm defects associated with infertility, and DNA damage via oxidative stress. Sperm defects were transient as they were not detected 10 days to 5 weeks postinjection.     

Combining proteomics and lipid analysis to unravel Confidor stress response in Saccharomyces cerevisiae

The yeast Saccharomyces cerevisiae is a useful model for studying the influence of different stress factors on eukaryotic cells. In this work we used the pesticide imidacloprid, in the Confidor formulation, as the stress factor and analyzed its influence on the metabolic activity, proteome and lipid content and composition of Saccharomyces cerevisiae yeast. During the cultivation of yeast, the lowest recommended application dose of Confidor (0.025%, v/v) was added to the growth media and its influence on the mitochondria, cytosol with microsomes, and the whole yeast cells was monitored. The results show that under the stress provoked by the toxic effects of Confidor, yeast cells density significantly decreased and the percentage of metabolically disturbed cells significantly increased comparing with untreated control. Also, there was a downregulation of majority of glycolytic, gluconeogenesis, and TCA cycle enzymes (Fba1, Adh1, Hxk2, Tal1, Tdh1,Tdh3, Eno1) thus providing enough acetyl‐CoA for the lipid restructuring and accumulation mechanism since we have found the changes in the cell and mitochondrial lipid content and FA composition. This data suggest that lipids could be the molecules that orchestrate the answer of the cells in the stress response to the Confidor treatment.     

Precision Medicine in Catecholaminergic Polymorphic Ventricular Tachycardia: JACC Focus Seminar 5/5

In this final of a 5-part Focus Seminar series on precision medicine, we focus on catecholaminergic polymorphic ventricular tachycardia (CPVT). This focus on CPVT allows us to take a “deep dive” and explore the full extent of the precision medicine opportunities for a single cardiovascular condition at a level that was not possible in the preceding articles. As a new paradigm presented in this article, it has become clear that CPVT can occur as either a typical or atypical form. Although there is a degree of overlap between the typical and atypical forms, it is notable that they arise due to different underlying genetic changes, likely exhibiting differing mechanisms of action, and presenting with different phenotypic features. The recognition of these differing forms of CPVT and their different etiologies and mechanisms is an important step toward implementing rapidly emerging precision medicine approaches that will tailor novel therapies to specific gene defects.     

Unusual clinical presentation of brown tumor in hemodialysis patients: two case reports

Brown tumor or osteoclastoma is a lytic bone tumor, which is common in secondary hyperparathyroidism (1.5–13%) in chronic dialysis patients, mainly in those with untreated renal osteodystrophy. Brown tumor appears as a result from excess osteoclast activity and consists of collections of osteoclasts intermixed with fibrous tissue and poorly mineralized woven bone. It can be manifested as a single or multiple bone lesions. Although invasive, it has no malignant potential and should be distinguished from giant cell tumors of the bone. Two unusual cases of brown tumor in dialysis patients are reported. We present a first patient with five subtotal parathyroidectomies between 2002 and 2009 and a tendency toward recurrence of secondary hyperparathyroidism (sHPTH). The double MRI check up could not reveal any ectopic parathyroid gland. Although the patient had permanently high PTH values, serum calcium level was never above the normal range. However, the brown tumor in the cervical spine was destructing the cervical vertebrae and required surgical intervention. Despite the conservative treatment with calcium and non-calcium-based binders and various forms of vitamin D, the patient’s clinical and biochemical condition improved only after the use of cinacalcet. The second patient, a 58-years-old female on chronic hemodialysis since 1998, was found with high PTH serum levels in 2009. The development of sHPTH was scintigraphically confirmed and surgically treated. During the late 2008, she started feeling pain, numbness and swelling of the 3rd right hand finger, prior to the full clinical manifestation of the tumor. The CT scan of the right hand showed osteolytic changes and soft tissue destruction of the middle phalanx of the 3rd right hand finger. This formation corresponded to an unusual presentation of brown tumor associated with sHPTH. As expected, after the parathyroidectomy, there was no marked change in the destructed bone of the 3rd right hand finger middle phalanx, but only a gradual improvement in the subjective clinical condition of the patient. Based on these two reports, we would recommend that in cases of severe or recurrent sHPTH either total parathyroidectomy or early administration of calcimimetics should be considered. Furthermore, the implementation of regular checkup and treatment according to the KDIGO guidelines should be advised and clinical appearance of any bone tumor immediately checked for an association with sHPTH, which is a rather common entity in dialysis patients.     

Human and Rat Glioma Growth,Invasion, and Vascularization in a Novel Chick Embryo Brain Tumor Model

The mechanisms that control the insidiously invasive nature of malignant gliomas are poorly understood, and their study would be facilitated by an in vivo model that is easy to manipulate and inexpensive. The developing chick embryo brain was assessed as a new xenograft model for the production, growth, and study of human and rat glioma cell lines. Three established glioma lines (U-87 MG, C6, and 9L) were injected into chick embryo brain ventricles on embryonic day (E) 5 and brains were examined after several days to two weeks after injection. All glioma lines survived, produced vascularized intraventricular tumors, and invaded the brain in a manner similar to that in rodents. Rat C6 glioma cells spread along vasculature and also invaded the neural tissue. Human U-87 glioma cells migrated along vasculature and exhibited slight invasion of neural tissue. Rat 9L gliosarcoma cells were highly motile, but migrated only along the vasculature. A derivative of 9L cells that stably expressed the cell surface adhesion molecule NgCAM/L1 was produced and also injected into chick embryo brain ventricles to see if this protein could facilitate tumor cell migration away from the vasculature into areas such as axonal tracts. 9L/NgCAM cells, however, did not migrate away from the vasculature and, thus, this protein alone cannot be responsible for diffuse invasiveness of some gliomas. 9L/NgCAM cell motility was assessed in vitro using sophisticated time-lapse microscopy and quantitative analysis, and was significantly altered compared to parental 9L cells. These studies demonstrate that the chick embryo brain is a successful and novel xenograft model for mammalian gliomas and demonstrate the potential usefulness of this new model for studying glioma tumor cell growth, vascularization, and invasiveness.     

Mining injuries in Serbian underground coal mines - A 10-year study

Mining, especially underground coal mining, has always been a dangerous occupation. Injuries, unfortunately, even those resulting in death, are one of the major occupational risks that all miners live with. Despite the fact that all workers are aware of the risk, efforts must be and are being made to increase the safety of mines. Injury monitoring and data analysis can provide us with valuable data on the causes of accidents and enable us to establish a correlation between the conditions in the work environment and the number of injuries, which can further lead to proper preventive measures. This article presents the data on the injuries in Serbian coal mines during a 10-year period (2000-2009). The presented results are only part of an ongoing study whose aim is to assess the safety conditions in Serbian coal mines and classify them according to that assessment.     

Antistaphylococcal activity of Inula helenium L. root essential oil: eudesmane sesquiterpene lactones induce cell membrane damage

The purpose of this study was to investigate the inhibitory/bactericidal activity and cell membrane effects of the hydrodistilled essential oil of Inula helenium L. roots against Staphylococcus aureus. Additionally, detailed chemical investigation was done in order to pinpoint the most active oil constituents and also the parts of these molecules responsible for their antimicrobial effect. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined using the broth microdilution method. The membrane-active nature of this oil was investigated by measuring the culture turbidity, leakage of phosphates, and 260-nm-absorbing material, together with lysis of the exposed cells. Finally, the effect of the oil on the cells was visualized using scanning electron microscopy (SEM). The chemical composition of the essential oil was analyzed using gas chromatography-mass spectrometry (GC-MS) and preparative medium-pressure liquid chromatography (MPLC). Chemical modification of the oil was performed using catalytic hydrogenation (H₂, Pd/C) and reduction with NaBH₄. The MIC and MBC values were 0.01 μl mL⁻¹ and 0.02 μl mL⁻¹, respectively. Membrane damage was demonstrated through increased permeability (phosphates and nucleic acid leakage), followed by lysis of the exposed cells, captured on SEM images. The most active constituents were alantolactone, isoalantolactone, and diplophyllin. The essential oil showed very potent antistaphylococcal activity, with obvious membrane-damaging effects. Sesquiterpene lactones were found to be the most active principles of the oil, whose eudesmane core olefinic bonds, along with the α,β-methylene-lactone ring, are essential structural parts responsible for the exhibited antimicrobial activity.     

Agalsidase therapy in patients with Fabry disease on renal replacement therapy: a nationwide study in Italy.

BACKGROUND: In Fabry disease, end-stage renal disease (ESRD) and severe neurologic and cardiac complications represent the leading causes of late morbidity and mortality. A comprehensive Italian nationwide survey study was conducted to explore changes in cardiac status and renal allograft function in Fabry patients on renal replacement therapy (RRT) and enzyme replacement therapy (ERT). METHODS: This study was designed as a cross-sectional survey study with prospective follow-up. Of the 34 patients identified via searches in registries, 31 males and 2 females who received RRT and ERT (agalsidase beta in 30 patients, agalsidase alpha in 3) were included. Left ventricular mass index (LVMI), interventricular septal thickness at end diastole (IVSD), left ventricular posterior wall thickness (LVPWT) and renal allograft function were assessed at ERT baseline and subsequently at yearly intervals. RESULTS: The patients in the dialysis and transplant groups had been started on dialysis at age 42.0 and 37.1 years (mean), respectively, and patients in the transplant group received their renal allograft at age 39.8 years (mean). The mean age at the start of ERT was similar, 44.1 and 44.6 years, respectively. The mean RRT follow-up was 61.1 and 110.6 months for dialysis and transplant patients, respectively, whereas the ERT duration was 45.1 and 48.4 months, respectively. Cardiac parameters increased in dialysis patients. In transplant patients, mean LVMI seemed to plateau during agalsidase therapy at a lower level as compared to baseline. Decline in renal allograft function was relatively mild (-1.92 ml/min/year). Agalsidase therapy was well tolerated. Serious ERT-unrelated events occurred more often in the dialysis group. CONCLUSIONS: Kidney transplantation should be the standard of care for Fabry patients progressing towards ESRD. Transplanted Fabry patients on ERT may do better than patients remaining on maintenance dialysis. Larger, controlled studies in Fabry patients with ESRD will have to demonstrate if ERT is able to change the trajectory of cardiac disease and can preserve graft renal function.