Micronucleus induction after whole-body microwave irradiation of rats

Adult male Wistar rats were exposed for 2 h a day, 7 days a week for up to 30 days to continuous 2,450 MHz radiofrequency microwave (rf/MW) radiation at a power density of 5-10 mW/cm(2). Sham-exposed rats were used as controls. After ether anesthesia, experimental animals were euthanized on the final irradiation day for each treated group. Peripheral blood smears were examined for the extent of genotoxicity, as indicated by the presence of micronuclei in polychromatic erythrocytes (PCEs). The results for the time-course of PCEs indicated significant differences (P<0.05) for the 2nd, the 8th and the 15th day between control and treated subgroups of animals. Increased influx of immature erythrocytes into the peripheral circulation at the beginning of the experiment revealed that the proliferation and maturation of nucleated erythropoietic cells were affected by exposure to the 2,450 MHz radiofrequency radiation. Such findings are indicators of radiation effects on bone-marrow erythropoiesis and their subsequent effects in circulating red cells. The incidence of micronuclei/1,000 PCEs in peripheral blood was significantly increased (P<0.05) in the subgroup exposed to rf/MW radiation after eight irradiation treatments of 2 h each in comparison with the sham-exposed control group. It is likely that an adaptive mechanism, both in erythrocytopoiesis and genotoxicity appeared in the rat experimental model during the subchronic irradiation treatment.     

Characterization of velogenic Newcastle disease viruses isolated from dead wild birds in Serbia during 2007

Avian paramyxoviruses type 1 or Newcastle disease viruses (NDV) are frequently recovered from wild birds and such isolates are most frequently of low virulence. Velogenic NDV are usually recovered from poultry and only occasionally from wild birds. Five NDV isolates were obtained from carcasses of four wild bird species during 2007 in Serbia: Mallard (Anas platyrhynchos), Eurasian Sparrowhawk (Accipiter nisus), feral Rock Pigeon (Columba livia), and Eurasian Collared Dove (Streptopelia decaocto). All the isolates have a typical fusion protein cleavage site motif of velogenic viruses ((112)R-R-Q-K-R-F(117)). The highest homology (99%) for the nucleotide sequences spanning the M and F gene of the studied isolates was with the genotype VII NDV isolate Muscovy duck/China(Fujian)/FP1/02. Phylogenetic analysis based on a partial F gene sequence showed that the isolates from wild birds cluster together with concurrent isolates from poultry in Serbia within the subgenotype VIId, which is the predominant pathogen involved currently in Newcastle disease outbreaks in poultry worldwide. It is unlikely that the wild birds played an important role in primary introduction or consequent spread of the velogenic NDV to domestic poultry in Serbia, and they probably contracted the virus from locally infected poultry.     

The hVps34‐SGK3 pathway alleviates sustained PI3K/Akt inhibition by stimulating mTORC1 and tumour growth

We explore mechanisms that enable cancer cells to tolerate PI3K or Akt inhibitors. Prolonged treatment of breast cancer cells with PI3K or Akt inhibitors leads to increased expression and activation of a kinase termed SGK3 that is related to Akt. Under these conditions, SGK3 is controlled by hVps34 that generates PtdIns(3)P, which binds to the PX domain of SGK3 promoting phosphorylation and activation by its upstream PDK1 activator. Furthermore, under conditions of prolonged PI3K/Akt pathway inhibition, SGK3 substitutes for Akt by phosphorylating TSC2 to activate mTORC1. We characterise 14h, a compound that inhibits both SGK3 activity and activation in vivo, and show that a combination of Akt and SGK inhibitors induced marked regression of BT‐474 breast cancer cell‐derived tumours in a xenograft model. Finally, we present the kinome‐wide analysis of mRNA expression dynamics induced by PI3K/Akt inhibition. Our findings highlight the importance of the hVps34‐SGK3 pathway and suggest it represents a mechanism to counteract inhibition of PI3K/Akt signalling. The data support the potential of targeting both Akt and SGK as a cancer therapeutic.     

Wood dust exposure in wood industry and forestry

The aim of the study was to determine occupational exposure in Croatian wood processing industry and forest workers to harmful effects of wood dust on the risk of nose, nasal cavity and lung carcinoma. Mass concentrations of respirable particles and total wood dust were measured at two wood processing plants, three woodwork shops, and one lumbering site, where 225 total wood dust samples and 221 respirable particle samples were collected. Wood dust mass concentration was determined by the gravimetric method. Mass concentrations exceeding total wood dust maximal allowed concentration (MAC, 3 mg/m3) were measured for beechwood and oakwood dust in 38% (79/206) of study samples from wood processing facilities (plants and woodwork shops). Mass concentrations of respirable particles exceeding MAC (1 mg/m3) were recorded in 24% (48/202) of samples from wood processing facilities (mean 2.38 +/- 2.08 mg/m3 in plants and 3.6 +/- 2.22 mg/m3 in woodwork shops). Thus, 13% (27/206) of work sites in wood processing facilities failed to meet health criteria according to European guidelines. Launching of measures to reduce wood dust emission to the work area is recommended.     

Morphology of healthy human parathyroid glands in cytologic smears

OBJECTIVE: To compare the morphology of different parenchymal cell types in healthy human parathyroid glands (HPGs) in cytologic smears with their structure on histologic sections and to establish criteria for their recognition in smears. STUDY DESIGN: The HPGs of 47 subjects (27 females and 20 males) were incidentally removed during surgery on the thyroid gland. The tissue of glands with a normal macroscopic and microscopic appearance was analyzed in cytologic smears and on histologic sections. RESULTS: In cytologic smears (as well on histologic sections), dark and light chief cells predominated. Dark chief cells, which were more numerous than light ones, had a smaller nucleus without a visible nucleolus. The nucleus of light chief cells was larger with 1 or 2 nucleoli visible. The cytoplasm of both types of chief cells was poorly defined, grey-blue and often vacuolated. In the smears, the cytoplasm of oxyphilic cells was dense, gray-rose and well defined. In dark oxyphilic cells, the nuclei were smaller and without a visible nucleolus. Light oxyphilic cells had a larger nucleus and visible nucleolus. CONCLUSION: The identification and distribution of 4 parenchymal cell subtypes in the smears of pathologically altered HPGs may yield insights into the possible role of these cells in a specific disease.     

Patients review: drug-induced movement disorders

Objective of this paper is to review drug-induced movement disorders (D-IMD) treated patients on Department of Neurology in University Hospital Osijek. We reviewed patients treated during 10 years period (from 1992 to 2002). Analysed group consisted of 14 patients. Reasons for hospitalisation were swallowing problems in 6 patients, neuroleptic malignant syndrome (NMS) in 3 patients, stroke in 2 patients, bolus choking in 2 patients, and speech disturbance in 1 patient. Working diagnosis for most of our patients was neurological disease, yet only later D-IMD diagnosis was established excluding primary neurological disease, or as associated disease to basic neurological disorder. Nine patients have diagnosed as Parkinson syndrome, 3 patients as NMS, and 4 as orolingual dyskinesia, either autonomously, or in combination with Parkinson syndrome. D-IMD was most frequently caused by neuroleptics. Thus the small number of patients hospitalised regarding this syndrome on Department of Neurology.     

Do parathyroid glands from individuals of different age and gender contain lymph vessels?

Whereas lymph vessels in some endocrine glands have been thoroughly investigated, data on these vessels in human parathyroid glands are often contradictory and deficient in available literature. Therefore, the aim of this study was to histomorphologically investigate whether lymph vessels could be found in human parathyroid glands postnatally and, if so, whether their presence was age- and gender-dependent. A total of 44 parathyroid glands from subjects of both genders, aged 4-90 years, were studied. The glands were divided into three groups. Those from the 1st and the 2nd age group demonstrated similar morphological structure of parenchyma with predominant chief cells with pale-staining cytoplasm, while the frequency of lymph vessels was lower in the 2nd group. Unlike in these groups, chief cells with dark- staining cytoplasm predominated in the glandular parenchyma of the 3rd age group where lymph vessels were not found in any of the examined glands. The frequency of lymph vessels in parathyroid glands was almost the same for both genders. Histomorphologic occurrence of lymph vessels coincided with the presence of endocrine cells with pale-staining cytoplasm, which allowed the assumption that lymph vessels were also one of the signs of functional activity of human parathyroid glands.     

Spray-Dried Cellulose Nanofibers as Novel Tablet Excipient

The purpose of this study was to evaluate the potential of cellulose nanofibers (also referred as microfibrillated cellulose, nanocellulose, nanofibrillated, or nanofibrillar cellulose) as novel tabletting material. For this purpose, physical and mechanical properties of spray-dried cellulose nanofibers (CNF) were examined, and results were compared to those of two commercial grades of microcrystalline cellulose (MCC), Avicel PH101 and Avicel PH102, which are the most commonly and widely used direct compression excipients. Chemically, MCC and CNF are almost identical, but their physical characteristics, like mechanical properties and surface-to-volume ratio, differ remarkably. The novel material was characterized with respect to bulk and tapped as well as true density, moisture content, and flow properties. Tablets made of CNF powder and its mixtures with MCC with or without paracetamol as model compound were produced by direct compression and after wet granulation. The tensile strength of the tablets made in a series of applied pressures was determined, and yield pressure values were calculated from the measurements. With CNF, both wet granulation and direct compression were successful. During tablet compression, CNF particles were less prone to permanent deformation and had less pronounced ductile characteristics. Disintegration and dissolution studies showed slightly faster drug release from direct compression tablets with CNF, while wet granulated systems did not have any significant difference.