University of Florence

About: University of Florence is a education organization based out in Florence, Toscana, Italy. It is known for research contribution in the topics: Population & Carbonic anhydrase. The organization has 27292 authors who have published 79599 publications receiving 2341684 citations. The organization is also known as: Università degli studi di Firenze & Universita degli studi di Firenze.

Soil enzymology: classical and molecular approaches

Abstract: It is still problematic to use enzyme activities as indicators of soil functions because: (1) enzyme assays determine potential and not real enzyme activities; (2) the meaning of measured enzyme activities is not known; (3) the assumption that a single enzyme activity is an indicator of nutrient dynamics in soil neglects that the many enzyme activities are involved in such dynamic processes; (4) spatio-temporal variations in natural environments are not always considered when measuring enzyme activities; and (5) many direct and indirect effects make difficult the interpretation of the response of the enzyme activity to perturbations, changes in the soil management, changes in the plant cover of soil, etc. This is the first review discussing the links between enzyme-encoding genes and the relative enzyme activity of soil. By combining measurements of enzyme activity in soil with expression (transcriptomics and proteomics) of genes, encoding the relative enzymes may contribute to understanding the mode and timing of microbial communities’ responses to substrate availability and persistence and stabilization of enzymes in the soil.

Genetic evidence for a novel familial Alzheimer's disease locus on chromosome 14

Abstract: Familial Alzheimer's disease (FAD) has been shown to be genetically heterogeneous, with a very small proportion of early onset pedigrees being associated with mutations in the amyloid precursor protein (APP) gene on chromosome 21, and some late onset pedigrees showing associations with markers on chromosome 19. We now provide evidence for a major early onset FAD locus on the long arm of chromosome 14 near the markers D14S43 and D14S53 (multipoint lod score z = 23.4) and suggest that the inheritance of FAD may be more complex than had initially been suspected.

Short Physical Performance Battery and all-cause mortality: systematic review and meta-analysis

Abstract: The Short Physical Performance Battery (SPPB) is a well-established tool to assess lower extremity physical performance status. Its predictive ability for all-cause mortality has been sparsely reported, but with conflicting results in different subsets of participants. The aim of this study was to perform a meta-analysis investigating the relationship between SPPB score and all-cause mortality. Articles were searched in MEDLINE, the Cochrane Library, Google Scholar, and BioMed Central between July and September 2015 and updated in January 2016. Inclusion criteria were observational studies; >50 participants; stratification of population according to SPPB value; data on all-cause mortality; English language publications. Twenty-four articles were selected from available evidence. Data of interest (i.e., clinical characteristics, information after stratification of the sample into four SPPB groups [0–3, 4–6, 7–9, 10–12]) were retrieved from the articles and/or obtained by the study authors. The odds ratio (OR) and/or hazard ratio (HR) was obtained for all-cause mortality according to SPPB category (with SPPB scores 10–12 considered as reference) with adjustment for age, sex, and body mass index. Standardized data were obtained for 17 studies (n = 16,534, mean age 76 ± 3 years). As compared to SPPB scores 10–12, values of 0–3 (OR 3.25, 95%CI 2.86–3.79), 4–6 (OR 2.14, 95%CI 1.92–2.39), and 7–9 (OR 1.50, 95%CI 1.32–1.71) were each associated with an increased risk of all-cause mortality. The association between poor performance on SPPB and all-cause mortality remained highly consistent independent of follow-up length, subsets of participants, geographic area, and age of the population. Random effects meta-regression showed that OR for all-cause mortality with SPPB values 7–9 was higher in the younger population, diabetics, and men. An SPPB score lower than 10 is predictive of all-cause mortality. The systematic implementation of the SPPB in clinical practice settings may provide useful prognostic information about the risk of all-cause mortality. Moreover, the SPPB could be used as a surrogate endpoint of all-cause mortality in trials needing to quantify benefit and health improvements of specific treatments or rehabilitation programs. The study protocol was published on PROSPERO (CRD42015024916).

The NAD metabolome — a key determinant of cancer cell biology

Abstract: NAD is a vital molecule in all organisms. It is a key component of both energy and signal transduction--processes that undergo crucial changes in cancer cells. NAD(+)-dependent signalling pathways are many and varied, and they regulate fundamental events such as transcription, DNA repair, cell cycle progression, apoptosis and metabolism. Many of these processes have been linked to cancer development. Given that NAD(+)-dependent signalling reactions involve the degradation of the molecule, permanent nucleotide resynthesis through different biosynthetic pathways is crucial for incessant cancer cell proliferation. This necessity supports the targeting of NAD metabolism as a new therapeutic concept for cancer treatment.

T helper 1 effector cells specific for Helicobacter pylori in the gastric antrum of patients with peptic ulcer disease.

Abstract: Chronic antral gastritis following Helicobacter pylori (Hp) infection is characterized by a cellular inflammatory infiltrate whose cytokines may represent a host-dependent factor influencing the outcome of the infection. The pattern of cytokines produced by the immunologically active cells in the gastric antrum was analyzed at the mRNA level in antral biopsies from five Hp-infected patients with duodenal ulcer and three Hp-negative dyspeptic controls. T cell clones were generated from parallel antral biopsies of the same Hp-infected patients and assessed for reactivity to Hp Ags, cytokine profile, and effector functions. Antral biopsies from all Hp-infected patients showed IFN-gamma, TNF-alpha, and IL-12, but not IL-4, mRNA expression, whereas no cytokine mRNA signal was found in the mucosa of controls. A total of 24 out of the 163 CD4+ T cell clones (15%) derived from Hp-infected patients proliferated in response to a Hp lysate; 11 clones (46%) also reacted with Cag-A, 2 with Vac-A, and 1 with urease. Upon Ag stimulation, 20 out of the 24 Hp-reactive clones (83%) produced IFN-gamma, but not IL-4 or IL-5 (Th1-like), whereas 4 produced IFN-gamma, IL-4, and IL-5 (Th0-like). All Hp-specific clones secreted high levels of TNF-alpha. At low T:B cell ratio, Hp-specific clones expressed Ag-dependent helper function for B cell proliferation and Ig production, whereas at higher T:B cell ratios, 15 Th1 and 2 Th0 clones lysed Ag-pulsed autologous EBV-transformed B cells. Results provide evidence for Hp-specific Th1 effectors in the gastric antrum of Hp-infected patients, where they may play a role in the genesis of either peptic ulcer or Hp-associated gastric B cell lymphoma.