543 research outputs found

    Water status and yield response to deficit irrigation and fertilization of three olive oil cultivars under the semi-arid conditions of Tunisia

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    Sustainability of olive production is possible by adopting the modern techniques of irrigation and fertilization. In Tunisia, olive trees are usually cultivated in poor soils, under semi-arid conditions characterized by water scarcity. This study investigated the effects of different water supply and fertilization on leaf water status and crop yield of three different olive oil varieties cultivated in central Tunisia, during four experimental seasons (2014-2017). Three treatments were examined: trees conducted under rainfed conditions (TRF), which represented the control treatment, trees irrigated with 50% ETc (T50) and, finally, trees irrigated with 50% ETc and with additional fertilization (T50F). Leaf water content and potential, yield and water use efficiency have been monitored on three different varieties, Chetoui, Chemlali, and Koroneiki, which are quite typical in the considered region. For all the growing seasons, midday leaf water potentials were measured from April to September. Midday leaf water potentials (MLWP) were generally higher for the two irrigated treatments (T50 and T50F) than for non-irrigated trees (TRF). As the season proceeded, MLWPs tended to decrease during summer for all the treatments and varieties. The lowest values were observed for the non-irrigated trees, varying between -3.25 MPa to -4.75 MPa. Relative leaf water content followed the same trends of midday leaf water potentials. Chetoui showed the lowest yield, which did not exceed 1530 Kg/(ha year), even for irrigated and fertilized trees. On the other hand, the yields of Chemlali and Koroneiki, cumulated in the four years, reached the maximum value of about 20 tons/ha. For these two varieties, the cumulated yield obtained in the control treatment (TRF) resulted significantly lower than the corresponding of the other two treatments (T50 and T50F). The highest irrigation water use efficiency (WUE) was estimated for Chemlali (T50) and (TRF). WUE was equal to 1.22 Kg/m3 for Koroneiki under fertigated treatment (T50F). Application of the only water supply (50% ETc) or associated with fertilizer improved the tree water status and increased the productivity of Chemlali and Koroneiki varieties

    Polarization gradient: exploring an original route for optical trapping and manipulation.

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    We report a study of the capabilities of an optical tweezer based on polarization gradient. We use a light polarization pattern that is able to simultaneously exert forces and torques in opposite directions depending on the particle's position. It allows to perform oscillatory displacements and control the sense of rotation of several particles inside a uniformly illuminated region. Unconventional trapping of spinning particles in circularly polarized fringes has been observed, which suggests the involvement of hydrodynamic forces

    Water extract of Cryphaea heteromalla (Hedw.) D. Mohr bryophyte as a natural powerful source of biologically active compounds

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    Bryophytes comprise of the mosses, liverworts, and hornworts. Cryphaea heteromalla, (Hedw.) D. Mohr, is a non-vascular lower plant belonging to mosses group. To the date, the most chemically characterized species belong to the liverworts, while only 3.2% and 8.8% of the species belonging to the mosses and hornworts, respectively, have been investigated. In this work, we present Folin–Ciocalteu and oxygen radical absorbance capacity (ORAC) data related to crude extracts of C. heteromalla obtained by three different extraction solvents: pure water (WT), methanol:water (80:20 v/v) (MET), and ethanol:water (80:20 v/v) (ETH). The water extract proved to be the best solvent showing the highest content of biophenols and the highest ORAC value. The C. heteromalla-WT extract was investigated by HPLC-TOF/MS (High Performance Liquid Chromatography-Time of Flight/Mass Spectrometry) allowing for the detection of 14 compounds, five of which were phenolic compounds, derivatives of benzoic, caffeic, and coumaric acids. Moreover, the C. heteromalla WT extract showed a protective effect against reactive oxygen species (ROS) generation induced by tert-butyl hydroperoxide (TBH) on the murine NIH-3T3 fibroblast cell line

    The effects of somatostatin analogues on liver volume and quality of life in polycystic liver disease: a meta-analysis of randomized controlled trials

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    A clear evidence on the benefits of somatostatin analogues (SA) on liver outcome in patients affected by polycystic liver disease is still lacking. We performed a meta-analysis of RCTs and a trial sequential analysis (TSA) evaluating the effects of SA in adult patients with polycystic liver disease on change in liver volume. As secondary outcome, we evaluated the effects on quality of life as measured by SF36-questionnaire. Six RCTs were selected with an overall sample size of 332 adult patients with polycystic liver disease (mean age: 46 years). Mean liver volume at baseline was 3289 ml in SA group and 3089 ml in placebo group. Overall, unstandardized mean difference in liver volume was − 176 ml (95%CI, − 406, 54; p < 0.133). Heterogeneity was low (I2:0%, p < 0.992). However, we performed a moderator analysis and we found that a higher eGFR significantly correlates to a more pronounced effect of SA on liver volume reduction (p = 0.036). Cumulative Z-curve in TSA did not reach either significance and futility boundaries or required information size. Three RCTs have evaluated Quality of life parameters measured by SF36-QOL questionnaire for a total of 124 patients; no significant difference was found on the effect of SA on QOL parameters when compared with placebo. The present meta-analysis revealed a potential effect of SA on reduction of liver volume and quality of life parameters, but results did not reach a statistical significance. These data could be explained by the need of further studies, as demonstrated through TSA, to reach an adequate sample size to confirm the beneficial outcomes of SAs treatment

    Characterization of highly frequent epitope-specific CD45RA(+)/CCR7(+/- )T lymphocyte responses against p53-binding domains of the human polyomavirus BK large tumor antigen in HLA-A*0201+ BKV-seropositive donors

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    Human polyomavirus BK (BKV) has been implicated in oncogenic transformation. Its ability to replicate is determined by the binding of its large tumor antigen (LTag) to products of tumor-suppressor genes regulating cell cycle, as specifically p53. We investigated CD8+ T immune responses to BKV LTag portions involved in p53 binding in HLA-A*0201+ BKV LTag experienced individuals. Peptides selected from either p53-binding region (LTag(351–450 )and LTag(533–626)) by current algorithms and capacity to bind HLA-A*0201 molecule were used to stimulate CD8+ T responses, as assessed by IFN-γ gene expression ex vivo and detected by cytotoxicity assays following in vitro culture. We observed epitope-specific immune responses in all HLA-A*0201+ BKV LTag experienced individuals tested. At least one epitope, LTag(579–587); LLLIWFRPV, was naturally processed in non professional antigen presenting cells and induced cytotoxic responses with CTL precursor frequencies in the order of 1/20'000. Antigen specific CD8+ T cells were only detectable in the CD45RA+ subset, in both CCR7+ and CCR7- subpopulations. These data indicate that widespread cellular immune responses against epitopes within BKV LTag-p53 binding regions exist and question their roles in immunosurveillance against tumors possibly associated with BKV infection

    Hepatic follicular lymphoma in an old patient with Crohn’s disease: a rare case and review of the literature

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    OBJECTIVE: Crohn’s Disease (CD) has been associated with non-Hodgkin lymphoma. Follicular Lymphoma (FL) limited to the liver is extremely rare, accounting for 1% to 4.4% of all Primary Hepatic Lymphoma (PHL). CASE PRESENTATION: In 2018, an 85-years old male patient with post-operative recurrence of ileal CD referred rare episodes of fever and mild diffuse abdominal pain. Since cholecystectomy in 2001, clinical history was characterized by recurrent episodes of cholangitis and common bile duct stones. In 2018, ultrasonography and MRI showed a solid focal hepatic lesion (FHL)(4.5 cm x 2.5 cm) in the IV hepatic segment. The radiographic aspect of the lesion was unusual. Initially, focal nodular hyperplasia was suspected. Clinical history of cholangitis and radiological findings subsequently suggested a diagnosis of Hepatic Abscess (HA). A progressive enlargement of the FHL (7.3 cm x 5.8 cm) despite antibiotic treatments, led to perform a liver biopsy. Histological and immunophenotypi-cal analysis of the FHL (7.5 cm x 5.4 cm) enabled a final diagnosis of FL. The “in situ” hybridization for Epstein-Barr virus (EBER) was negative. No additional lesions related to FL were initially detected, thus suggesting a very rare case of PHL in an old patient with CD never treated with thiopurines. CONCLUSIONS: This case report highlights the need to consider a rare diagnosis of FL of the liver in patients showing a challenging focal hepatic lesion of unknown origin

    Hepatic Notch1 deletion predisposes to diabetes and steatosis via glucose-6-phosphatase and perilipin-5 upregulation

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    Notch signaling pathways have recently been implicated in the pathogenesis of metabolic diseases. However, the role of hepatic Notch signaling in glucose and lipid metabolism remains unclear and needs further investigation as it might be a candidate therapeutic target in metabolic diseases such as nonalcoholic steatohepatitis (NASH) and nonalcoholic fatty liver disease (NAFLD). We used hepatocyte-specific Notch1 knockout (KO) mice and liver biopsies from NASH and NAFLD patients to analyze the role of Notch1 in glucose and lipid metabolism. Hepatocyte-specific Notch1 KO mice were fed with a high fat diet (HFD) or a regular diet (RD). We assessed the metabolic phenotype, glucose and insulin tolerance tests, and liver histology. Hepatic mRNA expression was profiled by Affymetrix Mouse Gene arrays and validated by quantitative reverse transcription PCR (qPCR). Akt phosphorylation was visualized by immunoblotting. Gene expression was analyzed in liver biopsies from NASH, NAFLD, and control patients by qPCR. We found that Notch1 KO mice had elevated fasting glucose. Gene expression analysis showed an upregulation of glucose-6-phosphatase, involved in the final step of gluconeogenesis and glucose release from glycogenolysis, and perilipin-5, a regulator of hepatic lipid accumulation. When fed with an HFD KO mice developed overt diabetes and hepatic steatosis. Akt was highly phosphorylated in KO animals and the Foxo1 target gene expression was altered. Accordingly, a reduction in Notch1 and increase in glucose-6-phosphatase and perilipin-5 expression was observed in liver biopsies from NAFLD/NASH compared with controls. Notch1 is a regulator of hepatic glucose and lipid homeostasis. Hepatic impairment of Notch1 expression may be involved in the pathogenesis of human NAFLD/NASH

    Ultrasonography of quadriceps femoris muscle and subcutaneous fat tissue and body composition by BIVA in chronic dialysis patients

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    Protein Energy Wasting (PEW) in hemodialysis (HD) patients is a multifactorial condition due to specific pathology-related pathogenetic mechanisms, leading to loss of skeletal muscle mass in HD patients. Computed Tomography and Magnetic Resonance Imaging still represent the gold standard techniques for body composition assessment. However, their widespread application in clinical practice is difficult and body composition evaluation in HD patients is mainly based on conventional anthropometric nutritional indexes and bioelectrical impedance vector analysis (BIVA). Little data is currently available on ultrasound (US)-based measurements of muscle mass and fat tissue in this clinical setting. The purpose of our study is to ascertain: (1) if there are differences between quadriceps rectus femoris muscle (QRFM) thickness and abdominal/thigh subcutaneous fat tissue (SFT) measured by US between HD patients and healthy subjects; (2) if there is any correlation between QRFM and abdominal/thigh SFT thickness by US, and BIVA/conventional nutritional indexes in HD patients. We enrolled 65 consecutive HD patients and 33 healthy subjects. Demographic and laboratory were collected. The malnutrition inflammation score (MIS) was calculated. Using B-mode US system, the QRFM and SFT thicknesses were measured at the level of three landmarks in both thighs (superior anterior iliac spine, upper pole of the patella, the midpoint of the tract included between the previous points). SFT was also measured at the level of the periumbilical point. The mono frequency (50 KHz) BIVA was conducted using bioelectrical measurements (Rz, resistance; Xc, reactance; adjusted for height, Rz/H and Xc/H; PA, phase angle). 58.5% were men and the mean age was 69 (SD 13.7) years. QRFM and thigh SFT thicknesses were reduced in HD patients as compared to healthy subjects (p &lt; 0.01). Similarly, also BIVA parameters, expression of lean body mass, were lower (p &lt; 0.001), except for Rz and Rz/H in HD patients. The average QRFM thickness of both thighs at top, mid, lower landmarks were positively correlated with PA and body cell mass (BCM) by BIVA, while negatively correlated with Rz/H (p &lt; 0.05). Abdominal SFT was positively correlated with PA, BCM and basal metabolic rate (BMR) (p &lt; 0.05). Our study shows that ultrasound QRFM and thigh SFT thicknesses were reduced in HD patients and that muscle ultrasound measurements were significantly correlated with BIVA parameters
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