Iron chelation effects on lipid peroxidation, inflammation and ventricular performance in a rat model of isoproterenol induced acute myocardial stress.

Acute cardiac pathologies represent one of the leading causes of death, while iron metabolism is recognized to be implicated in reactive oxygen species production, lipid peroxidation, and inflammation. The aim of the present study was to assess iron chelation effects in isoproterenol (ISO) induced acute cardiac stress. We divided male Wistar rats into preventive and secondary treatment groups, with the active arm consisting in deferiprone (DFP), a lipid permeable chelator. Mortality of ISO was 10-18.18% in both preventive and secondary groups. We analyzed serum and myocardial tissue parameters of inflammation, iron dynamics, and lipid peroxidation, accompanied by ultramicroscopy, histological, and ultrasound-derived parameters of left ventricular function. Results reveal that ISO-mediated lipid peroxidation and inflammation are alleviated by administration of DFP, with negligible effect on systemic ferroregulation dynamics and global ventricular function (as assessed by ultrasound). DFP administration after cardiovascular stress is associated with a decrease in lipid peroxidation and inflammation, without an improvement in gross left ventricular parameters.

Synchronous metastatic skull base chordoma to the breast: case report and literature review.

CLINICAL SCENARIO: During routine staging work-up for a left breast mass, a 68-year-old woman complained of dysphagia and dysphonia. During further investigations, a left-sided lesion at the foramen magnum was observed on brain imaging. Both lesions were biopsied and showed a classical chordoma. MANAGEMENT: The skull-base lesion and the breast lesion were surgically resected, and adjuvant radiotherapy was given. SUMMARY: Chordoma is a rare primary central nervous system tumour that seldom metastasizes. The lung is the most common site of metastasis. Synchronous breast metastasis from a skull-base chordoma is very rare, and a safe management option includes a maximum resection followed by adjuvant radiotherapy.

A novel missense mutation in the NADPH binding domain of CYBB abolishes the NADPH oxidase activity in a male patient with increased susceptibility to infections

Chronic granulomatous disease (CGD) is a primary immunodeficiency caused by mutations in the five structural genes (CYBB, CYBA, NCF1, NCF2, and NCF4) that typically results in a decrease in function or inability to generate a respiratory burst, leading to defective killing of pathogens, including fungi and intracellular bacteria. Mutations in CYBB, encoding the gp91 phox (also known as NOX2) result in X-linked CGD account for approximately 65% of CGD cases. Here, we aimed the characterization of a novel missense mutation c.1226C > A/p.A409E in the CYBB gene in a patient with X-linked CGD. Relevant clinical data of a male patient whose family was positive for XCGD was reviewed. Oxidative burst and NADPH protein expression was evaluated by flow cytometry, while Genetic analysis was performed by Sanger sequencing. Monocyte-derived macrophages (MDMs) were evaluated for their capacity for phagocytosis and growth suppression of the intracellular Mycobacterium tuberculosis (M. tuberculosis). We thus report the absence of an oxidative burst in the phagocytes of the patient. Flow cytometry evaluation revealed a normal expression of NADPH oxidase components in neutrophils and genetic analysis proved the existence of a novel missense c.1226C > A mutation in the CYBB gene resulting in p.A409E. Further, we have showed that the patient's MDMs were unhindered in their ability to take up mycobacteria normally. Instead, the MDMs failed to control the intracellular proliferation of M. tuberculosis, a phenotype that improved in the presence of recombinant human interferon-gamma (rhIFN-gamma). This work expands the genetic spectrum of X-linked CGD and demonstrates improvement in macrophage function in X91(+)CGD patient by rhIFN-gamma. 

New organophilic kaolin clays based on single-point grafted 3-aminopropyl dimethylethoxysilane.

In this study, the organophilization procedure of kaolin rocks with a monofunctional ethoxysilane- 3 aminopropyl dimethyl ethoxysilane (APMS) is depicted for the first time. The two-step organophilization procedure, including dimethyl sulfoxide intercalation and APMS grafting onto the inner hydroxyl surface of kaolinite (the mineral) layers was tested for three sources of kaolin rocks (KR, KC and KD) with various morphologies and kaolinite compositions. The load of APMS in the kaolinite interlayer space was higher than that of 3-aminopropyl triethoxysilane (APTS) due to the single-point grafting nature of the organophilization reaction. A higher long-distance order of kaolinite layers with low staking was obtained for the APMS, due to a more controllable organiphilization reaction. Last but not least, the solid state (29)Si-NMR tests confirmed the single-point grafting mechanism of APMS, corroborating monodentate fixation on the kaolinite hydroxyl facets, with no contribution to the bidentate or tridentate fixation as observed for APTS.

Experimental study on histological changes in the sinus membrane following sinus lift.

UNLABELLED: The aim of this study is to assess the histological changes in the sinus mucosa adjacent to the alloplastic material used for subantral augmentation. MATERIALS AND METHODS: The study included ten sheep and a dog. The first group of five sheep underwent a sinus lift procedure, using PerioGlas as an augmentation material; the second similar group of sheep was the control group. The dog underwent a sinus lift procedure, with PerioGlas augmentation, after the sinus membrane was intentionally perforated and two implants were placed in the same operative step. RESULTS: Scanning electron microscopy (SEM) of the sinus mucosa in the control group revealed cells without cilia between goblet cells. The cilia were uniformly arranged in sections in the same direction. Changes occurred in the sinus mucosa after grafting, such as drastic reduction of ciliated cells, which seemed to be replaced by goblet cells. In all sheep undergoing grafting, generalized fibrosis was found in the mucosal area that came into contact with PerioGlas. In two of the sheep in which grafting was performed, mucoid cysts with pseudo stratified ciliated epithelium were present. Even when the sinus mucosa was perforated (in the dog), the inflammatory process developed in the mucosa did not prevent the integration of the graft and implants. In conclusion, following the sinus lift procedure, changes occur in the sinus membrane to adapt to the new situation, without the appearance of chronic or acute suppurative processes.

Differential diagnosis between chronic granulocytic leukemia, polycythaemia vera and essential thrombocythemia using micro-and ultrastructural measurement data performed at the level of megakaryocyte.

The common features of chronic myeloproliferative disorders (CMDs) make the differential diagnosis on clinical or paraclinical basis to become more difficult, and validate the requirements for new methods of detailed diagnosis. Besides the cytogenetic methods, the megakaryocyte (MK) morphology is a valuable element of diagnosis included in the recent "en vogue" criteria. The purpose of this paper is to compare different morphological parameters in MKs from patients diagnosed with three CMDs and to establish a differential diagnosis of these disorders. Studies were performed on smears of bone marrow blood - for light microscope analysis -, and bone marrow biopsies - for transmission electron microscope (TEM) analysis - collected from six patients, two diagnosed with chronic granulocytic leukemia (CGL), two with polycythaemia vera (PV), and other two with essential thrombocythemia (ET). On the light microscope images, we observed important differences between the sizes of MKs and of MKs nuclei in CGL, PV, and ET. On the TEM images, we also noted important differences concerning the size and the aspect of nuclei, aspect of mitochondria, the amount and distribution of RER, Golgi apparatus and demarcation membrane system; the most important are the differences recorded in the number, distribution and sizes of vacuoles, alpha-granules and of the dense bodies. This study provides evidence that there are significant morphological differences between the cellular structures in the MKs from the patients with diagnosed with different CMDs, and thus sustains the utilization of this approach for establishing the differential diagnosis of CMDs.

The use of scanning electron microscopy in evaluating the effect of a bleaching agent on the enamel surface.

In this paper we present the results of an experiment with a commercial gel containing carbamide peroxide (CP) 15% (Opalescence 15% PF), aimed to assess the effects of this bleaching agent on the enamel surface of extracted human teeth, by using scanning electron microscopy (SEM). Opalescence 15% PF was applied on two quadrants of twelve extracted permanent, decay-free, human teeth, for 3 hours or 8 hours; for four teeth the application was performed once, while for eight teeth the treatment was repeated daily for 14 days (in order to simulate the usual clinical protocol of at-home bleaching). One quadrant of each tooth was used for control and the remaining quadrant was etched for 40 seconds with a gel containing 37% phosphoric acid. No differences concerning the micromorphology of tooth surface were observed by SEM, on the samples treated with Opalescence 15% PF once, for 3 or 8 hours, when compared to the control. Various, mainly minor changes occurred in samples treated with Opalescence 15% PF for 3 hours or 8 hours daily, for 14 days. On the other hand, the acid-etched samples had an irregular surface, which suggests important alterations of the prismatic structure of the enamel. These are the first studies of this type performed in Romania.

IP(3) receptor antagonist, 2-APB, attenuates cisplatin induced Ca2+-influx in HeLa-S3 cells and prevents activation of calpain and induction of apoptosis.

BACKGROUND AND PURPOSE: Cisplatin drives specific types of tumour cells to apoptosis. In this study we investigate the involvement of intracellular calcium ([Ca(2+)](i)) in triggering apoptosis in two different cell lines. As cisplatin is used for the treatment of several forms of cancer we choose HeLa-S3 and U2-OS as two examples of tumour cell lines. EXPERIMENTAL APPROACH: Cisplatin (1 nM-10 microM) was applied to HeLa-S3 and U2-OS cells and [Ca(2+)](i) measured with fluo-4, using laser scanning microscopy. Inositol-1,4,5-trisphosphate (IP(3)) receptors were visualized with immunostaining. Membrane conductances were measured with patch-clamp techniques. Levels of calpain and caspases were assessed by western blots and apoptotic cells were stained with Hoechst 33342 and counted. KEY RESULTS: Cisplatin increases [Ca(2+)](i) concentration-dependently in HeLa-S3 but not in U2-OS cells. This elevation of [Ca(2+)](i) depended on extracellular Ca(2+) but was reduced by the IP(3) receptor blocker, 2-APB. This effect was not due to a Ca(2+) release triggered by Ca(2+) entry. Immunostaining showed IP(3)-receptors (type 1-3) at the cellular membrane of HeLa-S3 cells, but not in U2-OS cells. Electrophysiological experiments showed an increased membrane conductance with cisplatin only when Ca(2+) was present extracellularly. Increase of [Ca(2+)](i) was related to the activation of calpain but not caspase-8 and triggered apoptosis in HeLa-S3 but not in U2-OS cells. CONCLUSIONS AND IMPLICATIONS: Our observations on the activation of IP(3)-receptors, calcium entry and apoptotic rate by cisplatin in specific carcinogenic cells might open new possibilities in the treatment of some forms of cancer.

The cyto- and genotoxicity of organotin compounds is dependent on the cellular uptake capability.

Organotin compounds have been widely used as stabilizers and anti-fouling agents with the result that they are ubiquitously distributed in the environment. Organotins accumulate in the food chain and potential effects on human health are disquieting. It is not known as yet whether cell surface adsorption or accumulation within the cell, or indeed both is a prerequisite for the toxicity of organotin compounds. In this study, the alkylated tin derivatives monomethyltin trichloride (MMT), dimethyltin dichloride (DMT), trimethyltin chloride (TMT) and tetramethyltin (TetraMT) were investigated for cyto- and genotoxic effects in CHO-9 cells in relation to the cellular uptake. To identify genotoxic effects, induction of micronuclei (MN), chromosome aberrations (CA) and sister chromatid exchanges (SCE) were analyzed and the nuclear division index (NDI) was calculated. The cellular uptake was assessed using ICP-MS analysis. The toxicity of the tin compounds was also evaluated after forced uptake by electroporation. Our results show that uptake of the organotin compounds was generally low but dose-dependent. Only weak genotoxic effects were observed after exposure of cells to DMT and TMT. MMT and TetraMT were negative in the test systems. After forced uptake by electroporation MMT, DMT and TMT induced significant DNA damage at non-cytotoxic concentrations. The results presented here indicate a considerable toxicological potential of some organotin species but demonstrate clearly that the toxicity is modulated by the cellular uptake capability.

Trimethylantimony dichloride causes genotoxic effects in Chinese hamster ovary cells after forced uptake.

In our study, we demonstrate that trimethylantimony dichloride (TMSb) does not induce micronucleus (MN) formation, chromosome aberrations (CA) or sister chromatid exchanges (SCE) under normal conditions in Chinese hamster ovary (CHO-9) cells in vitro up to an applied concentration of 1 mM, nor is it significantly cytotoxic. TMSb is taken up by the cells in a dose-dependent manner, but the percentage uptake of incubation substrate is low (max 0.05%). Intracellular TMSb concentration is two-fold increased after electroporation and under these forced uptake conditions MN formation is also significantly elevated. These data indicate that resistance to TMSb in CHO-9 cells occurs at the uptake and not at the intracellular level.

Forced uptake of trivalent and pentavalent methylated and inorganic arsenic and its cyto-/genotoxicity in fibroblasts and hepatoma cells.

Mammals are able to convert inorganic arsenic to mono-, di-, and trimethylated metabolites. In previous studies we have shown that the trivalent organoarsenic compounds are more toxic than their inorganic counterparts and that the toxicity is associated with the cellular uptake of the arsenicals. In the present study, we investigated cyto-/genotoxic effects of the arsenic compounds arsenate [As(i)(V)], arsenite [As(i)(III)], monomethylarsonic acid [MMA(V)], monomethylarsonous acid [MMA(III)], dimethylarsinic acid [DMA(V)], dimethylarsinous acid [DMA(III)], and trimethylarsine oxide [TMAO(V)] after an extended exposure time (24 h) and compared the uptake capabilities of fibroblasts (CHO-9 cells: Chinese hamster ovary) used for genotoxicity studies, with those of hepatic cells (Hep G2: hepatoma cell-line). To find out whether the arsenic compounds are bound to membranes or if they are present in the cytosol, the amount of arsenic was measured in whole-cell extracts and in membrane-removed cell extracts by inductively coupled plasma-mass spectrometry (ICP-MS). In addition, we forced the cellular uptake of the arsenic compounds into CHO-9 cells by electroporation and measured the intracellular arsenic concentrations before and after this procedure. Our results show that organic and inorganic arsenicals are taken up to a higher degree by fibroblasts compared to hepatoma cells. The arsenic metabolite DMA(III) was the most membrane permeable species in both cell lines and induced strong genotoxic effects in CHO-9 cells after an exposure time of 24 h. The uptake of all other arsenic species was relatively low (<1% by Hep G2 and <4% by CHO cells), but was dose-dependent. Electroporation increased the intracellular arsenic levels as well as the number of induced MN in CHO-9 cells. With the exception of As(i)(III) and DMA(III) in CHO-9 cells, the tested arsenic compounds were not bound to cell membranes, but were present in the cytosol. This may indicate the existence of DMA(III)-specific exporter proteins as are known for As(i)(III). Our results indicate that the uptake capabilities of arsenic compounds are highly dependent upon the cell type. It may be hypothesized that the arsenic-induced genotoxic effects observed in fibroblasts are due to the high uptake of arsenicals into this cell type. This may explain the high susceptibility of skin fibroblasts to arsenic exposure.

Uptake of inorganic and organic derivatives of arsenic associated with induced cytotoxic and genotoxic effects in Chinese hamster ovary (CHO) cells.

Humans are exposed to arsenic and their organic derivatives, which are widely distributed in the environment, via food, water, and to a lesser extent, via air. Following uptake, inorganic arsenic undergoes biotransformation to mono- and dimethylated metabolites. Recent findings suggest that the methylation reactions represent a toxification rather than a detoxification pathway. In the present study, the genotoxic effects and the cellular uptake of inorganic arsenic [arsenate, As(i)(V); arsenite, As(i)(III)] and the methylated arsenic species monomethylarsonic acid [MMA(V)], monomethylarsonous acid [MMA(III)], dimethylarsinic acid [DMA(V)], dimethylarsinous acid [DMA(III)], trimethylarsenic oxide [TMAO(V)] were investigated in Chinese hamster ovary (CHO-9) cells. The chemicals were applied at different concentrations (0.1 microM to 10 mM) for 30 min and 1 h, respectively. Cytotoxic effects were investigated by the trypan blue extrusion test and genotoxic effects by the assessment of micronucleus (MN) induction, chromosome aberrations (CA), and sister chromatid exchanges (SCE). Intracellular arsenic concentrations were determined by ICP-MS techniques. Our results show that MMA(III) and DMA(III) induce cytotoxic and genotoxic effects to a greater extent than MMA(V) or DMA(V). Viability was significantly decreased after incubation (1 h) of the cells with > or = 1 microM As(i)(III), > or = 1 microM As(i)(V), > or = 500 microM MMA(III), > or = 100 microM MMA(V), and 500 microM DMA(V) and > or = 0.1 microM DMA(III). TMAO(V) was not cytotoxic at concentrations up to 10 mM. A significant increase of the number of MN, CA and SCE was found for DMA(III) and MMA(III). As(i)(III + V) induced CA and SCE but no MN. TMAO(V), MMA(V) and DMA(V) were not genotoxic in the concentration range tested (up to 5 mM). The nuclear division index (NDI) was not affected by any of the tested arsenic compounds after a recovery period of 14 to 35 h. When the uptake of the chemicals was measured by ICP-MS analysis, it was found that only 0.03% MMA(V) and DMA(V), and 2% MMA(III), As(i)(III) and (V) were taken up by the cells. In comparison, 10% of the DMA(III) dose was taken up. The total intracellular concentration of all arsenic compounds increased with increasing arsenic concentrations in the culture medium. Taken together, these data demonstrate that arsenic compounds in the trivalent oxidation state exhibit the strongest genotoxic effects. Trivalent organoarsenic compounds are more membrane permeable than the pentavalent species. The potency of the DNA damage decreases in the order DMA(III) > MMA(III) > As(i)(III and V) > MMA(V) > DMA(V) > TMAO(V). We postulate that the induction of genotoxic effects caused by the methylated arsenic species is primarily dependent upon their ability to penetrate cell membranes.

Environmental distribution, analysis, and toxicity of organometal(loid) compounds.

The biochemical modification of the metals and metalloids mercury, tin, arsenic, antimony, bismuth, selenium, and tellurium via formation of volatile metal hydrides and alkylated species (volatile and involatile) performs a fundamental role in determining the environmental processing of these elements. In most instances, the formation of such species increases the environmental mobility of the element, and can result in bioaccumulation in lipophilic environments. While inorganic forms of most of these compounds are well characterized (e.g., arsenic, mercury) and some of them exhibit low toxicity (e.g., tin, bismuth), the more lipid-soluble organometals can be highly toxic. Methylmercury poisoning (e.g., Minamata disease) and tumor development in rats after exposure to dimethylarsinic acid or tributyltin oxide are just some examples. Data on the genotoxicity (and the neurotoxicity) as well as the mechanisms of cellular action of organometal(loid) compounds are, however, scarce. Many studies have shown that the production of such organometal(loid) species is possible and likely whenever anaerobic conditions (at least on a microscale) are combined with available metal(loid)s and methyl donors in the presence of suitable organisms. Such anaerobic conditions can exist within natural environments (e.g., wetlands, pond sediments) as well as within anthropogenic environmental systems (e.g., waste disposal sites and sewage treatments plants). Some methylation can also take place under aerobic conditions. This article gives an overview about the environmental distribution of organometal(loid) compounds and the potential hazardous effects on animal and human health. Genotoxic effects in vivo and in vitro in particular are discussed.

[Malignancy risk in some benign mammary lesions]. / Riscul malignizarii unor leziuni mamare benigne.

We analyzed retrospectively 821 patients operated on in our clinic for benign mammary lesions and for breast cancer. Histopathology identified in some cases associated benign and malign lesions. Atypical hyperplasia is considered significant risk factor for malignancy. Women in this category need close surveillance.

[Practical aspects in diagnosis and treatment of benign breast lesions]. / Elemente practice privind diagnosticul si tratamentul leziunilor mamare benigne.

We analyzed 444 patients operated on in our clinic. Triple test diagnosis is the modern trend. Surgical treatment is not justified in all cases. When needed, partial mastectomy is commonly used. Surgical principles must be respected for good cosmetic results. Histopathology only certifies the diagnostic.