Prognostic role of the CDNK1B V109G polymorphism in multiple endocrine neoplasia type 1

CDKN1B encodes the cyclin‐dependent kinase inhibitor p27/Kip1. CDKN1B mutations and polymorphisms are involved in tumorigenesis; specifically, the V109G single nucleotide polymorphism has been linked to different tumours with controversial results. Multiple endocrine neoplasia type 1 (MEN1) is a rare autosomal dominant syndrome, characterized by the development of different types of neuroendocrine tumours and increased incidence of other malignancies. A clear genotype–phenotype correlation in MEN1 has not been established yet. In this study, we assessed whether the CDKN1B V109G polymorphism was associated with the development of aggressive tumours in 55 consecutive patients affected by MEN1. The polymorphism was investigated by PCR amplification of germline DNA followed by direct sequencing. Baseline and follow‐up data of tumour types and their severity were collected and associated with the genetic data. MEN1‐related aggressive and other malignant tumours of any origin were detected in 16.1% of wild‐type and 33.3% of polymorphism allele‐bearing patients (P = NS). The time interval between birth and the first aggressive tumour was significantly shorter in patients with the CDKN1B V109G polymorphism (median 46 years) than in those without (median not reached; P = 0.03). Similarly, shorter was the time interval between MEN1 diagnosis and age of the first aggressive tumour (P = 0.02). Overall survival could not be estimated as 96% patients were still alive at the time of the study. In conclusion, CDKN1B V109G polymorphism seems to play a role in the development of aggressive tumours in MEN1.     

Structural and histomorphometric evaluations of ferutinin effects on the uterus of ovariectomized rats during osteoporosis treatment

AimsThe effects of chronic administration of Ferutinin (phytoestrogen found in the plants of genus Ferula), compared with those elicited by estradiol benzoate, were evaluated, following ovariectomy, on the uterus of ovariectomized rats as regard weight, size, structure and histomorphometry.Main methodsThe experimental study included 40 female Sprague–Dawley rats, assigned to two different protocols, i.e. preventive and recovering. In the preventive protocol, ferutinin (2 mg/kg/day) was orally administered for 30 days, starting from the day after ovariectomy; in the recovering protocol, ferutinin was administered, at the same dosage, for 30 days starting from the 60th day after ovariectomy, when osteoporosis was clearly established. Its effects were compared with those of estradiol benzoate (1.5 μg per rat twice a week, subcutaneously injected) vs. vehicle-treated ovariectomized controls and vehicle-treated sham-operated controls. Uteri were removed, weighed and analysed under both the structural and histomorphometrical points of view.Key findingsOur data show that ferutinin acts, similarly to estradiol benzoate, on the uterus stimulating endometrial and myometrial hypertrophy; this notwithstanding, the phytoestrogen ferutinin, in contrast to estrogen treatment, appears to increase apoptosis in uterine luminal and glandular epithelia.SignificanceFerutinin, used in osteoporosis treatment primarily for bone mass recovering, seems in line with an eventual protective function against uterine carcinoma, unlike estrogens so far employed in hormone replacement therapy (HRT).     

Towards life cycle sustainability assessment: an implementation to photovoltaic modules

Purpose

The main goal of the paper is to carry out the first implementation of sustainability assessment of the assembly step of photovoltaic (PV) modules production by Life Cycle Sustainability Assessment (LCSA) and the development of the Life Cycle Sustainability Dashboard (LCSD), in order to compare LCSA results of different PV modules. The applicability and practicability of the LCSD is reported thanks to a case study. The results show that LCSA can be considered a valuable tool to support decision-making processes that involve different stakeholders with different knowledge and background.

Method

The sustainability performance of the production step of Italian and German polycrystalline silicon modules is assessed using the LCSD. The LCSD is an application oriented to the presentation of an LCSA study. LCSA comprises life cycle assessment (LCA), life cycle costing and social LCA (S-LCA). The primary data collected for the German module are related to two different years, and this led to the evaluation of three different scenarios: a German 2008 module, a German 2009 module, and an Italian 2008 module.

Results and discussion

According to the LCA results based on Ecoindicator 99, the German module for example has lower values of land use [1.77 potential disappeared fractions (PDF) m²/year] and acidification (3.61 PDF m²/year) than the Italian one (land use 1.99 PDF m²/year, acidification 3.83 PDF m²/year). However, the German module has higher global warming potential [4.5E?C05 disability-adjusted life years (DALY)] than the Italian one [3.00E?05 DALY]. The economic costs of the German module are lower than the Italian one, e.g. the cost of electricity per FU for the German module is 0.12??/m² compared to the Italian 0.85??/m². The S-LCA results show significant differences between German module 2008 and 2009 that represent respectively the best and the worst overall social performances of the three considered scenarios compared by LCSD. The aggregate LCSD results show that the German module 2008 has the best overall sustainability performance and a score of 665 points out of 1,000 (and a colour scale of light green). The Italian module 2008 has the worst overall sustainability performance with a score of 404 points, while the German module 2009 is in the middle with 524 points.

Conclusions

The LCSA and LCSD methodologies represent an applicable framework as a tool for supporting decision-making processes which consider sustainable production and consumption. However, there are still challenges for a meaningful application, particularly the questions of the selection of social LCA indicators and how to weigh sets for the LCSD.     

Different involvement of autophagy in human malignant glioma cell lines undergoing irradiation and temozolomide combined treatments

Glioblastoma (GB) has a poor prognosis, despite current multimodality treatment. Beside surgical resection, adjuvant ionizing radiation (IR) combined with Temozolomide (TMZ) drug administration is the standard therapy for GB. This currently combined radio-chemotherapy treatment resulted in glial tumor cell death induction, whose main molecular death pathways are still not completely deciphered. In this study, the autophagy process was investigated, and in vitro modulated, in two different GB cell lines, T98G and U373MG (known to differ in their radiosensitivity), after IR or combined IR/TMZ treatments. T98G cells showed a high radiosensitivity (especially at low and intermediate doses), associated with autophagy activation, assessed by Beclin-1 and Atg-5 expression increase, LC3-I to LC3-II conversion and LC3B-GFP accumulation in autophagosomes of irradiated cells; differently, U373MG cells resulted less radiosensitive. Autophagy inhibition, using siRNA against BECN1 or ATG-7 genes, totally prevented decrease in viability after both IR and IR/TMZ treatments in the radiosensitive T98G cells, confirming the autophagy involvement in the cytotoxicity of these cells after the current GB treatment, contrary to U373MG cells. However, rapamycin-mediated autophagy, that further radiosensitized T98G, was able to promote radiosensitivty also in U373MG cells, suggesting a role of autophagy process in enhancing radiosensitivity. Taken together, these results might enforce the concept that autophagy-associated cell death might constitute a possible adjuvant therapeutic strategy to enhance the conventional GB treatment.     

Heme oxygenase-1 posttranslational modifications in the brain of subjects with Alzheimer disease and mild cognitive impairment

Alzheimer disease (AD) is a neurodegenerative disorder characterized by progressive cognitive impairment and neuropathology. Oxidative and nitrosative stress plays a principal role in the pathogenesis of AD. The induction of the heme oxygenase-1/biliverdin reductase-A (HO-1/BVR-A) system in the brain represents one of the earliest mechanisms activated by cells to counteract the noxious effects of increased reactive oxygen species and reactive nitrogen species. Although initially proposed as a neuroprotective system in AD brain, the HO-1/BVR-A pathophysiological features are under debate. We previously reported alterations in BVR activity along with decreased phosphorylation and increased oxidative/nitrosative posttranslational modifications in the brain of subjects with AD and those with mild cognitive impairment (MCI). Furthermore, other groups proposed the observed increase in HO-1 in AD brain as a possible neurotoxic mechanism. Here we provide new insights about HO-1 in the brain of subjects with AD and MCI, the latter condition being the transitional phase between normal aging and early AD. HO-1 protein levels were significantly increased in the hippocampus of AD subjects, whereas HO-2 protein levels were significantly decreased in both AD and MCI hippocampi. In addition, significant increases in Ser-residue phosphorylation together with increased oxidative posttranslational modifications were found in the hippocampus of AD subjects. Interestingly, despite the lack of oxidative stress-induced AD neuropathology in cerebellum, HO-1 demonstrated increased Ser-residue phosphorylation and oxidative posttranslational modifications in this brain area, suggesting HO-1 as a target of oxidative damage even in the cerebellum. The significance of these findings is profound and opens new avenues into the comprehension of the role of HO-1 in the pathogenesis of AD.     

Toxigenic Vibrio cholerae in the Aquatic Environment of Mathbaria, Bangladesh

Toxigenic Vibrio cholerae, rarely isolated from the aquatic environment between cholera epidemics, can be detected in what is now understood to be a dormant stage, i.e., viable but nonculturable when standard bacteriological methods are used. In the research reported here, biofilms have proved to be a source of culturable V. cholerae, even in nonepidemic periods. Biweekly environmental surveillance for V. cholerae was carried out in Mathbaria, an area of cholera endemicity adjacent to the Bay of Bengal, with the focus on V. cholerae O1 and O139 Bengal. A total of 297 samples of water, phytoplankton, and zooplankton were collected between March and December 2004, yielding eight V. cholerae O1 and four O139 Bengal isolates. A combination of culture methods, multiplex-PCR, and direct fluorescent antibody (DFA) counting revealed the Mathbaria aquatic environment to be a reservoir for V. cholerae O1 and O139 Bengal. DFA results showed significant clumping of the bacteria during the interepidemic period for cholera, and the fluorescent micrographs revealed large numbers of V. cholerae O1 in thin films of exopolysaccharides (biofilm). A similar clumping of V. cholerae O1 was also observed in samples collected from Matlab, Bangladesh, where cholera also is endemic. Thus, the results of the study provided in situ evidence for V. cholerae O1 and O139 in the aquatic environment, predominantly as viable but nonculturable cells and culturable cells in biofilm consortia. The biofilm community is concluded to be an additional reservoir of cholera bacteria in the aquatic environment between seasonal epidemics of cholera in Bangladesh.     

Redox thermodynamics of the Fe(III)/Fe(II) couple of human myeloperoxidase in its high-spin and low-spin forms

Myeloperoxidase (MPO) (donor, hydrogen peroxide oxidoreductase, EC 1.11.1.7) is the most abundant neutrophil enzyme and catalyzes predominantly the two-electron oxidation of ubiquitous chloride (Cl-), to generate the potent bleaching oxidant hypochlorous acid (HOCl), thus contributing to bacterial killing and inflammatory reactions of neutrophils. Here, the thermodynamics of the one-electron reduction of the ferric heme in its ferric high-spin and cyanide-bound low-spin forms were determined through spectroelectrochemical experiments. The E(o)' values for free and cyanide-bound MPO (5 and -37 mV, respectively, at 25 degrees C and pH 7.0) are significantly higher than those of other heme peroxidases. Variable-temperature experiments revealed that the enthalpic stabilization of ferric high-spin MPO is much weaker than in other heme peroxidases and is exactly compensated by the entropic change upon reduction. In contrast to those of other heme peroxidases, the stabilization of the ferric cyanide-bound MPO is also very weak and fully entropic. This peculiar behavior is discussed with respect to the MPO-typical covalent heme to protein linkages as well as to the published structures of ferric MPO and its cyanide complex and the recently published structure of lactoperoxidase as well as the physiological role of MPO in bacterial killing.     

Redox thermodynamics of the ferric-ferrous couple of wild-type synechocystis KatG and KatG(Y249F)

Crystal structures and mass spectrometric analyses of catalase-peroxidases (KatGs) from different organisms revealed the existence of a peculiar distal Met-Tyr-Trp cross-link. The adduct appears to be important for the catalase but not the peroxidase activity of bifunctional KatG. To examine the effect of the adduct on enzyme redox properties and functions, we have determined the thermodynamics of ferric reduction for wild-type KatG and KatG(Y249F), whose tyrosine-to-phenylalanine mutation prevents cross-link formation. At 25 degrees C and pH 7.0, the reduction potential of wild-type KatG is found to be -226 +/- 10 mV, remarkably lower than the published literature values. The reduction potential of KatG(Y249F) is very similar (-222 +/- 10 mV), but variable temperature experiments revealed compensatory differences in reduction enthalpies and entropies. In both proteins, the oxidized state is enthalpically stabilized over the reduced state, but entropy is lost on reduction, which is in strong contrast to horseradish peroxidase, which also features a much more pronounced enthalpic stabilization of the ferriheme. With both proteins, the midpoint potential increased linearly with decreasing pH. We discuss whether the observed redox thermodynamics reflects the differences in structure and function between bifunctional KatG and monofunctional peroxidases.     

Carcinogenic Effects in a Phenylketonuria Mouse Model

Phenylketonuria (PKU) is a metabolic disorder caused by impaired phenylalanine hydroxylase (PAH). This condition results in hyperphenylalaninemia and elevated levels of abnormal phenylalanine metabolites, among which is phenylacetic acid/phenylacetate (PA). In recent years, PA and its analogs were found to have anticancer activity against a variety of malignancies suggesting the possibility that PKU may offer protection against cancer through chronically elevated levels of PA. We tested this hypothesis in a genetic mouse model of PKU (PAH^enu2) which has a biochemical profile that closely resembles that of human PKU. Plasma levels of phenylalanine in homozygous (HMZ) PAH^enu2 mice were >12-fold those of heterozygous (HTZ) littermates while tyrosine levels were reduced. Phenylketones, including PA, were also markedly elevated to the range seen in the human disease. Mice were subjected to 7,12 dimethylbenz[a]anthracene (DMBA) carcinogenesis, a model which is sensitive to the anticancer effects of the PA derivative 4-chlorophenylacetate (4-CPA). Tumor induction by DMBA was not significantly different between the HTZ and HMZ mice, either in total tumor development or in the type of cancers that arose. HMZ mice were then treated with 4-CPA as positive controls for the anticancer effects of PA and to evaluate its possible effects on phenylalanine metabolism in PKU mice. 4-CPA had no effect on the plasma concentrations of phenylalanine, phenylketones, or tyrosine. Surprisingly, the HMZ mice treated with 4-CPA developed an unexplained neuromuscular syndrome which precluded its use in these animals as an anticancer agent. Together, these studies support the use of PAH^enu2 mice as a model for studying human PKU. Chronically elevated levels of PA in the PAH^enu2 mice were not protective against cancer.