The Arabidopsis Mitochondrial Nucleoid-Associated Protein WHIRLY2 is Required for a Proper Response to Salt Stress

In the last years, plant organelles have emerged as central coordinators of responses to internal and external stimuli which can induce stress. Mitochondria play a fundamental role as stress sensors being part of a complex communication network between the organelles and nucleus. Among the different environmental stresses, salt stress poses a significant challenge and requires efficient signaling and protective mechanisms. By using the why2 T-DNA insertion mutant and a novel knockout mutant prepared by CRISPR Cas9 mediated genome editing, this study revealed that WHIRLY2 is crucial in protecting mitochondrial DNA (mtDNA) integrity during salt stress. Loss-of-function mutants show an enhanced sensitivity to salt stress. The disruption of WHIRLY2 causes the impairement of mtDNA repair that results in the accumulation of aberrant recombination products, coinciding with severe alterations in nucleoid integrity and overall mitochondria morphology besides a compromised redox-dependent response and mis-regulation of antioxidant enzymes. The results of this study revealed that WHIRLY2 mediated structural features in mitochondria (nucleoid compactness, cristae) are important for an effective response to salt stress.

The Role of Glutamine Synthetase (GS) and Glutamate Synthase (GOGAT) in the Improvement of Nitrogen Use Efficiency in Cereals

Cereals are the most broadly produced crops and represent the primary source of food worldwide. Nitrogen (N) is a critical mineral nutrient for plant growth and high yield, and the quality of cereal crops greatly depends on a suitable N supply. In the last decades, a massive use of N fertilizers has been achieved in the desire to have high yields of cereal crops, leading to damaging effects for the environment, ecosystems, and human health. To ensure agricultural sustainability and the required food source, many attempts have been made towards developing cereal crops with a more effective nitrogen use efficiency (NUE). NUE depends on N uptake, utilization, and lastly, combining the capability to assimilate N into carbon skeletons and remobilize the N assimilated. The glutamine synthetase (GS)/glutamate synthase (GOGAT) cycle represents a crucial metabolic step of N assimilation, regulating crop yield. In this review, the physiological and genetic studies on GS and GOGAT of the main cereal crops will be examined, giving emphasis on their implications in NUE.

Quantitative phosphoproteomics reveals novel roles of cAMP in plants

3',5'-cyclic adenosine monophosphate (cAMP) is finally recognized as an essential signaling molecule in plants where cAMP-dependent processes include responses to hormones and environmental stimuli. To better understand the role of 3',5'-cAMP at the systems level, we have undertaken a phosphoproteomic analysis to elucidate the cAMP-dependent response of tobacco BY-2 cells. These cells overexpress a molecular "sponge" that buffers free intracellular cAMP level. The results show that, firstly, in vivo cAMP dampening profoundly affects the plant kinome and notably mitogen-activated protein kinases, receptor-like kinases, and calcium-dependent protein kinases, thereby modulating the cellular responses at the systems level. Secondly, buffering cAMP levels also affects mRNA processing through the modulation of the phosphorylation status of several RNA-binding proteins with roles in splicing, including many serine and arginine-rich proteins. Thirdly, cAMP-dependent phosphorylation targets appear to be conserved among plant species. Taken together, these findings are consistent with an ancient role of cAMP in mRNA processing and cellular programming and suggest that unperturbed cellular cAMP levels are essential for cellular homeostasis and signaling in plant cells.

Comparative Analysis of Bioactive Compounds in Two Globe Artichoke Ecotypes Sanitized and Non-Sanitized from Viral Infections

Globe artichoke ecotypes sanitized from plant pathogen infections are characterized by high vegetative vigor, productivity, and quality of capitula. The recent availability on the market of these plants has renewed the interest of farmers and pharmaceutical industries in the crop. Globe artichoke exhibits interesting nutraceutical properties due to the high content of health-promoting bioactive compounds (BACs), such as polyphenols, that could be extracted from waste biomass. The production of BACs depends on several factors including the plant portion considered, the globe artichoke variety/ecotype, and the physiological status of the plants, linked to biotic and abiotic stresses. We investigated the influence of viral infections on polyphenol accumulation in two Apulian late-flowering ecotypes "Locale di Mola tardivo" and "Troianella", comparing sanitized virus-free material (S) vs. naturally virus-infected (non-sanitized, NS) plants. Transcriptome analysis of the two ecotypes highlighted that differentially expressed genes (DEGs), in the two tested conditions, were mainly involved in primary metabolism and processing of genetic/environmental information. The up-regulation of the genes related to the biosynthesis of secondary metabolites and the analysis of peroxidase activity suggested that their modulation is influenced by the phytosanitary status of the plant and is ecotype-dependent. Conversely, the phytochemical analysis showed a remarkable decrease in polyphenols and lignin accumulation in S artichokes compared to NS plants. This unique study analyzes the potential of growing vigorous, sanitized plants, in order to have high amounts of 'soft and clean' biomass, finalized for BAC extraction for nutraceutical purposes. This, in turn, opens new perspectives for a circular economy of sanitized artichokes, in line with the current phytosanitary standards and sustainable development goals.

Chloroplast-localized GUN1 contributes to the acquisition of basal thermotolerance in Arabidopsis thaliana

Heat stress (HS) severely affects different cellular compartments operating in metabolic processes and represents a critical threat to plant growth and yield. Chloroplasts are crucial for heat stress response (HSR), signaling to the nucleus the environmental challenge and adjusting metabolic and biosynthetic functions accordingly. GENOMES UNCOUPLED 1 (GUN1), a chloroplast-localized protein, has been recognized as one of the main players of chloroplast retrograde signaling. Here, we investigate HSR in Arabidopsis wild-type and gun1 plantlets subjected to 2 hours of HS at 45°C. In wild-type plants, Reactive Oxygen Species (ROS) accumulate promptly after HS, contributing to transiently oxidize the cellular environment and acting as signaling molecules. After 3 hours of physiological recovery at growth temperature (22°C), the induction of enzymatic and non-enzymatic antioxidants prevents oxidative damage. On the other hand, gun1 mutants fail to induce the oxidative burst immediately after HS and accumulate ROS and oxidative damage after 3 hours of recovery at 22°C, thus resulting in enhanced sensitivity to HS. These data suggest that GUN1 is required to oxidize the cellular environment, participating in the acquisition of basal thermotolerance through the redox-dependent plastid-to-nucleus communication.

Salt stress in olive tree shapes resident endophytic microbiota

Olea europaea L. is a glycophyte representing one of the most important plants in the Mediterranean area, both from an economic and agricultural point of view. Its adaptability to different environmental conditions enables its cultivation in numerous agricultural scenarios, even on marginal areas, characterized by soils unsuitable for other crops. Salt stress represents one current major threats to crop production, including olive tree. In order to overcome this constraint, several cultivars have been evaluated over the years using biochemical and physiological methods to select the most suitable ones for cultivation in harsh environments. Thus the development of novel methodologies have provided useful tools for evaluating the adaptive capacity of cultivars, among which the evaluation of the plant-microbiota ratio, which is important for the maintenance of plant homeostasis. In the present study, four olive tree cultivars (two traditional and two for intensive cultivation) were subjected to saline stress using two concentrations of salt, 100 mM and 200 mM. The effects of stress on diverse cultivars were assessed by using biochemical analyses (i.e., proline, carotenoid and chlorophyll content), showing a cultivar-dependent response. Additionally, the olive tree response to stress was correlated with the leaf endophytic bacterial community. Results of the metabarcoding analyses showed a significant shift in the resident microbiome for plants subjected to moderate salt stress, which did not occur under extreme salt-stress conditions. In the whole, these results showed that the integration of stress markers and endophytic community represents a suitable approach to evaluate the adaptation of cultivars to environmental stresses.

GUN1 involvement in the redox changes occurring during biogenic retrograde signaling

Chloroplast biogenesis requires a tight communication between nucleus and plastids. By retrograde signals, plastids transmit information about their functional and developmental state to adjust nuclear gene expression, accordingly. GENOMES UNCOUPLED 1 (GUN1), a chloroplast-localized protein integrating several developmental and stress-related signals, is one of the main players of retrograde signaling. Here, we focused on the interplay between GUN1 and redox regulation during biogenic retrograde signaling, by investigating redox parameters in Arabidopsis wild type and gun1 seedlings. Our data highlight that during biogenic retrograde signaling superoxide anion (O₂^-) and hydrogen peroxide (H₂O₂) play a different role in response to GUN1. Under physiological conditions, even in the absence of a visible phenotype, gun1 mutants show low activity of superoxide dismutase (SOD) and ascorbate peroxidase (APX), with an increase in O₂^- accumulation and lipid peroxidation, suggesting that GUN1 indirectly protects chloroplasts from oxidative damage. In wild type seedlings, perturbation of chloroplast development with lincomycin causes H₂O₂ accumulation, in parallel with the decrease of ROS-removal metabolites and enzymes. These redox changes do not take place in gun1 mutants which, in contrast, enhance SOD, APX and catalase activities. Our results indicate that in response to lincomycin, GUN1 is necessary for the H₂O₂-dependent oxidation of cellular environment, which might contribute to the redox-dependent plastid-to nucleus communication.

Functional Validation of Glutamine synthetase and Glutamate synthase Genes in Durum Wheat near Isogenic Lines with QTL for High GPC

Durum wheat (Triticum turgidum L. ssp. durum) is a minor crop grown on about 17 million hectares of land worldwide. Several grain characteristics determine semolina's high end-use quality, such as grain protein content (GPC) which is directly related to the final products' nutritional and technological values. GPC improvement could be pursued by considering a candidate gene approach. The glutamine synthetase (GS)/glutamate synthase (GOGAT) cycle represents a bottleneck in the first step of nitrogen assimilation. QTL for GPC have been located on all chromosomes, and several major ones have been reported on 2A and 2B chromosomes, where GS2 and Fd-GOGAT genes have been mapped. A useful and efficient method to validate a putative QTL is the constitution of near-isogenic lines (NILs) by using the marker found to be associated to that QTL. Here, we present the development of two distinct sets of heterogeneous inbred family (HIF)- based NILs segregating for GS2 and Fd-GOGAT genes obtained from heterozygous lines at those loci, as well as their genotypic and phenotypic characterizations. The results allow the validation of the previously identified GPC QTL on 2A and 2B chromosomes, along with the role of these key genes in GPC control.

Cyclic AMP mediates heat stress response by the control of redox homeostasis and ubiquitin-proteasome system

Heat stress (HS), causing impairment in several physiological processes, is one of the most damaging environmental cues for plants. To counteract the harmful effects of high temperatures, plants activate complex signalling networks, indicated as HS response (HSR). Expression of heat shock proteins (HSPs) and adjustment of redox homeostasis are crucial events of HSR, required for thermotolerance. By pharmacological approaches, the involvement of cAMP in triggering plant HSR has been recently proposed. In this study, to investigate the role of cAMP in HSR signalling, tobacco BY-2 cells overexpressing the 'cAMP-sponge', a genetic tool that reduces intracellular cAMP levels, have been used. in vivo cAMP dampening increased HS susceptibility in a HSPs-independent way. The failure in cAMP elevation during HS caused a high accumulation of reactive oxygen species, due to increased levels of respiratory burst oxidase homolog D, decreased activities of catalase and ascorbate peroxidase, as well as down-accumulation of proteins involved in the control of redox homeostasis. In addition, cAMP deficiency impaired proteasome activity and prevented the accumulation of many proteins of ubiquitin-proteasome system (UPS). By a large-scale proteomic approach together with in silico analyses, these UPS proteins were identified in a specific cAMP-dependent network of HSR.

Cyclic AMP: A Polyhedral Signalling Molecule in Plants

The cyclic nucleotide cAMP (3',5'-cyclic adenosine monophosphate) is nowadays recognised as an important signalling molecule in plants, involved in many molecular processes, including sensing and response to biotic and abiotic environmental stresses. The validation of a functional cAMP-dependent signalling system in higher plants has spurred a great scientific interest on the polyhedral role of cAMP, as it actively participates in plant adaptation to external stimuli, in addition to the regulation of physiological processes. The complex architecture of cAMP-dependent pathways is far from being fully understood, because the actors of these pathways and their downstream target proteins remain largely unidentified. Recently, a genetic strategy was effectively used to lower cAMP cytosolic levels and hence shed light on the consequences of cAMP deficiency in plant cells. This review aims to provide an integrated overview of the current state of knowledge on cAMP's role in plant growth and response to environmental stress. Current knowledge of the molecular components and the mechanisms of cAMP signalling events is summarised.

Influence of Homogenization Time and Speed on Rheological and Volatile Composition in Olive-Based Pâtés

The influence of the homogenization time and speed on rheological and volatile composition in olive-based pâtés was studied. Five experimental trials were performed applying different combinations of time and speed homogenization: 1, 3, and 5 min at 12,000 rpm and 4000, 8000, and 12,000 rpm at 5 min. The obtained results showed that the processing parameters of the homogenization step significantly influenced the rheological and sensory properties of olive-based pâtés. Both time and speed influenced the rheological properties of the product. The increase of homogenization time and speed determined a significant reduction of hardness and syneresis. As regards color indices, significantly higher L* values were obtained when intermediate time and speed conditions were applied, whereas a* and b* indices showed a not univocal behavior. Both time and speed variables also influenced the volatile fraction of the pâtés (higher homogenization speed and time corresponded to higher terpenes and aldehydes).

Cochlear implant in prelingually deafened oralist adults: speech perception outcomes, subjective benefits and quality of life improvement

The aim of this study is to report our results in a group of prelingually deafened adults, who followed an oralist rehabilitation programme, and submitted to cochlear implant at our institution. We evaluated 30 prelingually deafened adult patients, 18 males and 12 females, median age 35 years, of a group of 36 prelingually deafened adult patients consecutively submitted to unilateral cochlear implantation at the ENT Unit of the University of Pisa. After implantation, patients achieved significant benefits in terms of speech perception skills, including the ability to have telephone conversations in some cases, quality of life and their own perception of disability. According to literature data, the results herein reported are quite variable but generally satisfactory. Procedures other than traditional speech perception measures should be used to evaluate the benefits of cochlear implant in such patients, to compressively evaluate the global benefits, not only in terms of speech perception, but also in terms of quality of life and daily life.

A review of new insights on the association between hearing loss and cognitive decline in ageing

Age-related hearing loss (ARHL) has a multifactorial pathogenesis and it is an inevitable hearing impairment associated with reduction of communicative skills related to ageing. Increasing evidence has linked ARHL to more rapid progression of cognitive decline and incidental dementia. Many aspects of daily living of elderly people have been associated to hearing abilities, showing that hearing loss (HL) affects the quality of life, social relationships, motor skills, psychological aspects and function and morphology in specific brain areas. Epidemiological and clinical studies confirm the assumption of a relationship between these conditions. However, the mechanisms are still unclear and are reviewed herein. Long-term hearing deprivation of auditory inputs can impact cognitive performance by decreasing the quality of communication leading to social isolation and depression and facilitate dementia. On the contrary, the limited cognitive skills may reduce the cognitive resources available for auditory perception, increasing the effects of HL. In addition, hearing loss and cognitive decline may reflect a 'common cause' on the auditory pathway and brain. In fact, some pathogenetic factors are recongised in common microvascular disease factors such as diabetes, atherosclerosis and hypertension. Interdisciplinary efforts to investigate and address HL in the context of brain and cognitive ageing are needed. Surprisingly, few studies have been adressed on the effectiveness of hearing aids in changing the natural history of cognitive decline. Effective interventions with hearing aids or cochlear implant may improve social and emotional function, communication, cognitive function and positively impact quality of life. The aim of this review is to overview new insights on this challenging topic and provide new ideas for future research.

Glutamine synthetase in Durum Wheat: Genotypic Variation and Relationship with Grain Protein Content

Grain protein content (GPC), is one of the most important trait in wheat and its characterized by a very complex genetic control. The identification of wheat varieties with high GPC (HGPC), as well as the characterization of central enzymes involved in these processes, are important for more sustainable agricultural practices. In this study, we focused on Glutamine synthetase (GS) as a candidate to study GPC in wheat. We analyzed GS expression and its enzymatic activity in different tissues and phenological stages in 10 durum wheat genotypes with different GPC. Although each genotype performed quite differently from the others, both because their genetic variability and their adaptability to specific environmental conditions, the highest GS activity and expression were found in genotypes with HGPC and vice versa the lowest ones in genotypes with low GPC (LGPC). Moreover, in genotypes contrasting in GPC bred at different nitrogen regimes (0, 60, 140 N Unit/ha) GS behaved differently in diverse organs. Nitrogen supplement increased GS expression and activity in roots of all genotypes, highlighting the key role of this enzyme in nitrogen assimilation and ammonium detoxification in roots. Otherwise, nitrogen treatments decreased GS expression and activity in the leaves of HGPC genotypes and did not affect GS in the leaves of LGPC genotypes. Finally, no changes in GS and soluble protein content occurred at the filling stage in the caryopses of all analyzed genotypes.

Anticancer agents interacting with membrane glucose transporters

The altered metabolism observed in cancer cells generally consists in increased glucose uptake and glycolytic activity. This is associated with an overexpression of glucose transporter proteins (GLUTs), which facilitate glucose uptake across the plasma membrane and play a crucial role in the survival of cancer cells. Therefore GLUTs are considered as suitable targets for the treatment of cancer. Herein we review some of the most relevant GLUT inhibitors that have been recently developed as prospective anticancer agents.

Idiopathic sensorineural hearing loss in the only hearing ear

A retrospective chart review was used for 31 patients with sudden, progressive or fluctuating sensorineural hearing loss (SHL) in the only hearing ear who had been consecutively evaluated at the ENT, Audiology and Phoniatrics Unit of the University of Pisa. The group of patients was evaluated with a complete history review, clinical evaluation, imaging exam (MRI, CT), audiologic tests (tone and speech audiometry, tympanometry, study of stapedial reflexes, ABR and otoacoustic emission) evaluation. In order to exclude genetic causes, patients were screened for CX 26 and CX30 mutations and for mitochondrial DNA mutation A1555G. Patients with sudden or rapidly progressive SHL in the only hearing ear were treated with osmotic diuretics and corticosteroids. In patients who did not respond to intravenous therapy we performed intratympanic injections of corticosteroid. Hearing aids were fitted when indicated and patients who developed severe to profound SHL were scheduled for cochlear implant surgery. The aim of this study is to report and discuss the epidemiology, aetiopathogenesis, therapy and clinical characteristic of patients affected by SHL in the only hearing hear and to discuss the issues related to the cochlear implant procedure in some of these patients, with regard to indications, choice of the ear to implant and results.

Predictors of outcome following a short multimodal rehabilitation program for patients with whiplash associated disorders

BACKGROUND

Patients with whiplash associated disorders (WAD) may present with physical and psychological symptoms which persist long after the initial onset of pain. Several studies have shown that therapeutic exercise for motor and sensorimotor control combined with manual therapy in a multimodal rehabilitation (MMR) program is effective at improving pain and disability in patients with neck disorders. To date, no studies have investigated which self-reported physical or psychological symptoms are predictive of response to this MMR program.

AIM

To determine which baseline features can predict outcome following a 3-week MMR program in patients with WAD.

DESIGN

Observational prospective cohort study.

SETTING

Outpatient rehabilitation clinic.

POPULATION

Thirty-seven patients aged >18 years with a diagnosis of WAD grade II or III.

METHODS

The MMR program included manual therapy, motor control and sensorimotor control training according to the clinical impairments of each patient. Patients were assessed before and after treatment for their physical and psychological symptoms by means of self-reported questionnaires. Regression models were estimated with pain intensity, disability and post-traumatic stress symptoms (PTSS) as outcomes.

RESULTS

After treatment, patients exhibited significant improvements in all evaluated outcomes (all P<0.01). Regression models accounting for 35% and 36% of the variance in pain intensity outcomes included average pain intensity over the previous week and pain catastrophizing as significant predictors. Disability and pain catastrophizing were predictors of changes in disability following the MMR program explaining 49% of the variance in the model. Furthermore, higher PTSS at baseline was a significant predictor of PTSS after treatment, explaining 55% of the variance in the model.

CONCLUSION

Improved outcomes on pain intensity, disability and PTSS following a MMR program could be partially predicted based on the patient's initial presentation.

CLINICAL REHABILITATION IMPACT

This knowledge may assist clinicians in predicting outcome following a MMR program inclusive of specific exercise therapy and manual therapy in patients with WAD.

Dysregulated biomarkers induce distinct pathways in preterm birth

OBJECTIVE

To document racial disparity in biomarker concentrations in maternal/fetal plasma and amniotic fluid between African Americans and European Americans with spontaneous preterm birth (PTB; cases) and normal term birth (controls), and their contribution to distinct pathophysiological pathways of PTB.

DESIGN

Nested case-control study.

SETTING

The Perinatal Research Center, Nashville, Tennessee, USA.

SAMPLE

Maternal and fetal plasma and amniotic fluid samples were collected from 105 cases (59 African American and 46 European American) and 86 controls (40 African American and 46 European American).

METHODS

Thirty-six biomarkers were analysed using the protein microarray approach.

MAIN OUTCOME MEASURES

Differences in biomarker concentrations between cases and controls of different races in maternal, fetal and intra-amniotic compartments, and the risk of PTB. Dysregulated biomarker-induced PTB pathways associated with PTB in each race were determined using ingenuity pathway analysis (IPA).

RESULTS

Racial disparity was observed in biomarker concentrations in each compartment between cases and controls: amniotic fluid, IL8 and MIP1α differed between case and controls in European Americans, whereas ANGPT2, Eotaxin, ICAM-1, IL-1β, IL1RA, RANTES and TNFα differed between case and controls in African Americans. In both races the FAS ligand, MCP-3 and TNFR-I differed between cases and controls. For fetal plasma, ANGPT2, Eotaxin, FGF basic, ICAM-1, IGF-I, IL10, IL-1β, IL2, IP10 KGF, MCP-3, MIP1α, PDGF-BB, TGFα, TGFβ1, TIMP1, TNFα, TNFR-I, TNFR-II and VEGF differed between cases and controls in European Americans, whereas only MMP7 differed between cases and controls in African Americans. IL-8 differed between cases and controls in both races. For maternal plasma, IL1RA, MMP7 and VEGF differed between cases and controls in European Americans, whereas ANGPT2, FGF basic, IL-1β, IL5, IL6R, KGF, MCP-3, MIP1α, TIMP1 and TNFα differed between cases and controls in African Americans. ANG, IL8 and TNFR-I differed between cases and controls in both races.

CONCLUSIONS

We conclude that: (1) biomarker concentrations in maternal, fetal and intra-amniotic compartments differ between cases and controls; (2) there is racial disparity in the biomarker profile in each of the compartments; (3) substantial numbers of dysregulated fetal plasma biomarkers contribute to PTB in European Americans, whereas maternal plasma biomarkers contribute to PTB in African Americans; and (4) both inflammation and haematological functions are associated with PTB in European Americans, but maternal proinflammatory changes dominate PTB in African Americans. Biomarker analyses document racial disparity and the distinct pathophysiological contributions from different compartments that can determine pregnancy outcome.

Simultaneous care and melanoma: preliminary report about the psychoncological approach

AIM

The main aim of the study was to investigate the efficacy of a "take-in- charge" model of advanced stage melanoma patients by a multidisciplinary team and highlight the psychological patterns of the disease.

METHODS

The study sample involved 44 patients, 27 females and 17 males, who were given a "Questionnaire on Health Status SF-12" which provides two synthetic indexes, one related to physical health PCS-12, and the other to mental health MCS-12. The statistical data was collected through a preliminary analysis of principal components P.C. A., carried out with SPSS software.

RESULTS

Comparing the scores obtained by the PCS and MCS indexes, the mean score is low: 6.52 out of 10 for PCS and 3.23 out of 10 for MCS. At first consultation, there is evidence which supports patients' need for psycho-oncological support. By dividing the sample patients into two subgroups, cutaneous melanoma and visceral melanoma, it should be noted that the first group obtained a mean of 4.75 for PCS and 3.77 for MCS and the second group 7.53 for PCS and 2.92 for MCS respectively. Therefore, the results show, at first consultation, a more complex situation for patients with cutaneous melanoma.

CONCLUSION

The results of the study highlight the need to supply some form of psycho-oncological support to help patients while they adapt to the disease. Furthermore, different problems and different coping styles also emerged depending on whether the patient has cutaneous or visceral melanoma. The study therefore demonstrates the need to take into account such variables when devising a personal care system centered on the patient.

Sudden Sensorineural Hearing Loss: MR Imaging

Hearing loss greater than 30 dB over three contiguous pure-tone frequencies occurring within a three day period is defined as sudden hearing loss. It is usually sensorineural (SSNHL), unilateral and appears as an otologic emergency. SSNHL has many possibile etiologies such as: labyrinthine viral infection, ischemic or hemorrhagic illness, trauma, immuno-mediated inner ear disease, tumor, inner ear malformation, and an imbalance between perilymphatic and endolymphatic fluid pressure. Nevertheless in almost 80% of cases SSNHL belongs to the idiopathic category because the etiology is unknown. The aim of this study was to test the diagnostic impact of two MR devices. Fifteen cases of SSNHL studied with a 1.5 T unit in our hospital between January 2006 and December 2008 within two weeks of the onset were retrospectively evaluated. Since January 2009 three more patients affected by SSNHL have been scanned with a 3T MR unit. We discuss the diagnostic sensitivity, clinical usefulness and the cost-benefit ratio of the MR systems.

Topical interests and the mitigation of search engine bias

Search engines have become key media for our scientific, economic, and social activities by enabling people to access information on the web despite its size and complexity. On the down side, search engines bias the traffic of users according to their page ranking strategies, and it has been argued that they create a vicious cycle that amplifies the dominance of established and already popular sites. This bias could lead to a dangerous monopoly of information. We show that, contrary to intuition, empirical data do not support this conclusion; popular sites receive far less traffic than predicted. We discuss a model that accurately predicts traffic data patterns by taking into consideration the topical interests of users and their searching behavior in addition to the way search engines rank pages. The heterogeneity of user interests explains the observed mitigation of search engines' popularity bias.

A role for the 72 kDa gelatinase (MMP-2) and its inhibitor (TIMP-2) in human parturition, premature rupture of membranes and intraamniotic infection

OBJECTIVE

Degradation of the extracellular matrix in fetal membranes has been implicated in the process of parturition and rupture of membranes. Matrix metalloproteinases (MMPs) are enzymes capable of degrading extracellular matrix including collagen. Tissue inhibitors of matrix metalloproteinases (TIMPs) inhibit the activity of MMPs by covalently binding to the enzymes. MMP-2 degrades Type IV collagen and TIMP-2 is its specific inhibitor. The objective of this study was to determine if human parturition, rupture of membranes (term and preterm) and microbial invasion of the amniotic cavity (MIAC) are associated with changes in the concentrations of MMP-2 and TIMP-2 in amniotic fluid.

STUDY DESIGN

A cross-sectional study was conducted with women in the following categories: 1) term with intact membranes, in labor and not in labor; 2) preterm labor and intact membranes who delivered at term, who delivered preterm and preterm labor with MIAC; 3) preterm premature rupture of membranes (PROM) with and without infection; 4) term and preterm PROM not in labor; and 5) midtrimester. MMP-2 and TIMP-2 concentrations in amniotic fluid were determined using sensitive and specific immunoassays.

RESULTS

The concentration of TIMP-2 increased with advancing gestational age (r = 0.6, p < 0.001). No correlation was found between MMP-2 concentrations and gestational age. Human parturition and rupture of membranes (term and preterm) and in patients with intact membranes were not associated with changes in the amniotic fluid MMP-2 concentrations. In contrast, 1) patients with spontaneous labor (term and preterm) had significantly lower median concentrations of TIMP-2 compared to those not in labor (p < 0.05 for both); 2) MIAC in women with preterm labor and preterm PROM was associated with a significant decrease in amniotic fluid TIMP-2 concentrations (p < 0.04 for both comparisons); 3) Rupture of the membranes (term and preterm) was also associated with a significant decrease in the amniotic fluid TIMP-2 concentrations (p < 0.05 and p < 0.03, respectively).

CONCLUSIONS

Human parturition (preterm and term), rupture of fetal membranes (term and preterm) and intraamniotic infection are associated with a significant decrease in amniotic fluid TIMP-2 concentrations.

5-Fluorouracil and folinic acid with or without CPT-11 in advanced colorectal cancer patients: a multicenter randomised phase II study of the Southern Italy Oncology Group

PURPOSE

The combination regimen CPT-11 plus bolus and infusion 5-fluorouracil (5-FU) with high-dose leucovorin (hybrid regimen LV5FU2) has been tested for activity and toxicity against advanced colorectal carcinoma in a randomised, multicenter phase II trial.

PATIENTS AND METHODS

A total of 102 chemotherapy-naïve patients were randomised in a 1:2 fashion to receive: leucovorin 100 mg/m2 administered as a two-hour infusion before 5-FU 400 mg/m2 as an intravenous bolus, and FU 600 mg/m2 as a 22-hour infusion immediately after 5-FU bolus injection repeated on days 1 and 2 (LV5FU2 regimen, arm A, 34 patients) or CPT-11 at 180 mg/m2 (150 mg/m2 for patients of age > or = 70 and < 75 years) only on day 1 immediately before LV5FU2 therapy (LV5FU2 + CPT-11 regimen, arm B 68 patients). Both treatments were repeated every two weeks. The presence of a calibration arm assured consistency and more realistic evaluation of results achieved with the LV5FU2 + CTP-II regimen.

RESULTS

Thirty-three and sixty-four patients were evaluable in arm A and B, respectively. The overall response rate was 18% in arm A (95% CI: 7%-34%) and 40% in arm B (95% CI: 28%-52%). Median time to progression, median duration of response and survival were similar in both groups. Responders (CR + PR) survived statistically longer than non-responders only in arm B (20 vs. 10 months, P = 0.0016). All patients were evaluable for toxicity which was mild in both groups; gastrointestinal disturbances were the most common. There were no treatment-related deaths. Grade 3-4 toxicity was uncommon in both arms.

CONCLUSIONS

The addition of CPT-11 to the hybrid LV5FU2 regimen provided a significant overall response rate (40%) with relatively mild toxicity. The overall response rate was 18% in patients treated with LV5FU2 alone in the calibration arm. Thus, considering other encouraging data from the literature, the CPT-11 + FU-LV combination therapy can be regarded as a new, very effective treatment option for first-line treatment of advanced colorectal cancer patients.

Matrix metalloproteinases-9 in preterm and term human parturition

OBJECTIVE

Spontaneous rupture of the fetal membranes occurs after the commencement of labor in 90% of cases. Recent evidence indicates that the process of parturition requires not only an increase in myometrial contractility and cervical ripening, but also degradation of extracellular matrix in fetal membranes (i.e., leakage of fibronectin into cervico-vaginal secretions). This study was undertaken to determine if parturition is associated with in vivo evidence of increased bioavailability of matrix metalloproteinases-9 (MMP-9) and its inhibitor, tissue inhibitor of metalloproteinases-1(TIMP-1).

METHODS

A cross-sectional study was conducted with women in the following categories: 1) midtrimester (n = 25); 2) preterm labor and intact membranes in the absence of intraamniotic infection (n = 78); 3) term not in labor (n = 25); and 4) term with intact membranes in labor (n = 25). MMP-9, and TIMP-1 were measured using sensitive and specific immunoassays.

RESULTS

1) Spontaneous labor at term was associated with a significant increase in MMP-9 but not in TIMP-1.2) Women with preterm labor who delivered prematurely had significantly higher concentrations of MMP-9 but not TIMP-1 in amniotic fluid than those with preterm labor who delivered at term. 3) The concentrations of TIMP-1 decreased with advancing gestational age. In contrast, MMP-9 concentrations did not change with advancing gestational age.

CONCLUSIONS

Spontaneous human parturition is associated with specific changes in the enzymatic machinery responsible for extracellular matrix degradation.

Epirubicin, folinic acid, fluorouracil, and etoposide in the treatment of advanced gastric cancer: phase II study of the Southern Italy Oncology Group (GOIM)

In the authors' previous experience, the addition of epidoxorubicin to the FA-FU regimen obtained a better response rate than that of FA-FU alone in patients with advanced gastric cancer. Furthermore, considering the good efficacy and mild toxicity observed with the addition of etoposide to the FA-FU combination in the German study, the authors conducted a trial to explore the efficacy and tolerability of the ELFE regimen (epirubicin, folinic acid, fluorouracil, and etoposide) in previously untreated advanced gastric cancer patients. Of the 55 patients entered, 51 were evaluable for efficacy. Four complete responses (8%) and 21 partial responses (41%) were observed, with an overall response rate of 49% (95% CI: 35-63%). The median duration of response and survival were 6 and 8 months, respectively. Responder patients showed a significantly better median survival duration than nonresponders (12 vs. 4 months, respectively; p < 0.0001). Toxicity was evaluated in all patients: only 1 patient refused to continue therapy despite low toxicity. As expected, the major toxicities observed were gastrointestinal disturbance, leukopenia, and loss of hair. In conclusion, the ELFE combination regimen appears to be effective and well tolerated for the treatment of advanced gastric cancer patients.

Treatment of advanced adenocarcinomas of the exocrine pancreas and the gallbladder with 5-fluorouracil, high dose levofolinic acid and oral hydroxyurea on a weekly schedule. Results of a multicenter study of the Southern Italy Oncology Group (G.O.I.M.)

BACKGROUND

To date there is no established chemotherapeutic treatment for patients with unresectable locally advanced and/or metastatic carcinomas of the exocrine pancreas or the gallbladder. A multicenter Phase II trial has been performed by the Southern Italy Oncology Group with the aim of evaluating the clinical effectiveness and tolerability of weekly 5-fluorouracil (5-FU) in modulation with intravenous (i.v.) high dose levofolinic acid and oral hydroxyurea.

METHODS

A total of 70 patients fulfilling the standard eligibility for a Phase II study were enrolled in the trial. Forty patients had advanced pancreatic adenocarcinoma and 30 had advanced gallbladder carcinoma. The treatment schedule was: levofolinic acid, 100 mg/m2, in 500 mL of normal saline over 2-hour infusion followed by 5-FU, 600 mg/m2 i.v. bolus, and oral hydroxyurea, 1000 mg/m2, for 1 day every week for 6 consecutive weeks followed by 15 days of rest.

RESULTS

Among the 40 patients with pancreatic adenocarcinoma, 5 (12.5%; 95% confidence level [CL], 8.5-16.5%) showed a partial response with a median duration of 5.6+ months, and 13 had stable disease. Twenty-two patients progressed. Median survival was 5.8 months. Among patients with advanced gallbladder carcinoma, 9 of 30 had a partial response (30%; 95% CL, 26-34%) with a median duration of 6.5 months, and 8 (27%) had stabilization of disease. Thirteen patients showed progressive disease. Median overall survival was 8 months. Toxicity was mild, with Grade 1 to 2 leukopenia and gastrointestinal toxicity the most frequent side effects. No chemotherapy-related deaths were observed.

CONCLUSIONS

5-FU in modulation with i.v. levofolinic acid and oral hydroxyurea on a weekly schedule is well tolerated by the vast majority of patients with locally advanced and/or metastatic carcinoma of the pancreas or the gallbladder. Although response rate and overall survival for patients with pancreatic adenocarcinoma are far from acceptable, the 30% overall response rate achieved in patients with advanced gallbladder carcinoma suggests that 5-FU in modulation with levofolinic acid and hydroxyurea is active in this neoplasm. The combination of modulated 5-FU with other antineoplastic drugs seems worthy of clinical testing in further controlled trials.