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1.
J Frailty Aging ; 13(2): 172-178, 2024.
Article in English | MEDLINE | ID: mdl-38616374

ABSTRACT

BACKGROUND: Older patients in hemodialysis have high prevalence of malnutrition that is often associated with rapid weight loss till cachexia. OBJECTIVES: We aimed to investigate whether in older patients undergoing hemodialysis the association between poor nutritional status and mortality may be independent of comorbidities and other risk factors. DESIGN: Retrospective longitudinal study. SETTING: Unit of Nephrology, Dialysis and Kidney Transplantation of the Policlinic Hospital of Milan, Milan, Italy. PARTICIPANTS: A total of 107 prevalent patients undergoing hemodialysis for at least three months. MEASUREMENTS: Sociodemographic, clinical, and biological data were recorded. Unintentional weight loss (UWL) was defined as loss of body weight > 5% in 3 months or > 10% in 6 months. We computed a 21-item Frailty Index that included clinical conditions associated with malnutrition and mortality in this population. Unadjusted and adjusted Cox proportional hazard models were performed to test the association of UWL, albumin and transferrin levels with death. Survival analyses based on Kaplan-Meier estimates were performed. RESULTS: Patients' age was 79 (±7.7) years; 38 (35%) were women. Thirty-one patients (29%) died during follow-up. Eighteen (16.8%) patients experienced UWL during the follow-up period. UWL was positively associated with death in the unadjusted model and even after the progressive inclusion of potential confounders. Low albumin levels were positively associated with death only in the unadjusted and partially adjusted models while low transferrin levels were not associated with death in none of the models. Mortality was significantly higher in those patients experiencing both UWL and albumin levels below 3.5 mg/dL. CONCLUSIONS: In older patients undergoing chronic hemodialysis UWL is associated with mortality independently of comorbidities and other risk factors. Patients presenting both UWL and low albumin levels were those experiencing the worst outcomes in terms of mortality.


Subject(s)
Malnutrition , Nutritional Status , Humans , Female , Aged , Aged, 80 and over , Male , Longitudinal Studies , Retrospective Studies , Malnutrition/epidemiology , Weight Loss , Albumins , Transferrins
2.
Article in English | MEDLINE | ID: mdl-38626842

ABSTRACT

BACKGROUND AND OBJECTIVES: In a hospital radiopharmacy with 2a operational level, including the preparation of radiopharmaceuticals from prepared and approved reagent kits, it is common to have a single activimeter or dose calibrator for labeling and fractionation, and to perform the quality controls of the 99mTc-radiopharmaceuticals. In certain cases, the accumulation of radioactive material or accidental contamination of the work area causes the background to exceed the limits to carry out the radiochemical purity analyses and it is necessary to look for viable alternatives. In this work, a Geiger Müller detector (equipped with a probe for measuring surface contamination) frequently used for radioprotection purposes, was validated as an alternative and its performance was compared against the activimeter for 99mTc-radiopharmaceuticals. MATERIALS AND METHODS: Using [99mTc]pertechnetate, systematic studies of error analyses and detector response to activity concentration, activity and measurement time were carried out in liquid matrices and in paper. The results were compared against an activimeter calibrated for [99mTc]Tc. RESULTS: The developed method was used to determine the radiochemical purity of the compounds [99mTc]Tc-MDP and [99mTc]Tc-MIBI by ascending paper chromatography tests, obtaining comparable values to those measured with an activimeter in the same system (within 1% uncertainty) and using the method of vial partitioning in a dedicated equipment. CONCLUSIONS: This work demonstrates that a Geiger Müller detector with a probe for measuring surface contamination can be adequately used to replace other equipment in the control of radiochemical purity in the hospital radiopharmacy.


Subject(s)
Quality Control , Radiopharmaceuticals , Radiopharmaceuticals/analysis , Technetium/analysis , Calibration , Sodium Pertechnetate Tc 99m/analysis
3.
J Frailty Aging ; 12(3): 244-246, 2023.
Article in English | MEDLINE | ID: mdl-37493386

ABSTRACT

Older persons with chronic kidney disease (CKD) undergoing hemodialysis represent a growing portion of patients characterized by high vulnerability but still marginally studied. This study aimed at exploring the relationship between the number of prescriptions and fractures in older patients with CKD undergoing hemodialysis. A 24-item Frailty Index (FI) based on sociodemographic, clinical and biological data was computed. Unadjusted and adjusted logistic regression models were performed to test the association of prescribed medications with history of fractures. A total of 107 older patients undergoing hemodialysis (38 [35.5%] women, mean age 79.1 standard deviation, SD=7.7) were included in the study. Mean number of prescribed medications was 9.9 (SD=3.9) and was significantly associated with fractures (OR 1.18, 95% CI 1.06-1.32, p=0.003), even after adjustment for potential confounders (OR 1.16, 95% CI 1.03-1.30, p=0.016). If these results will be confirmed, interventions based on deprescribing will become essential in older persons undergoing hemodialysis.


Subject(s)
Frailty , Renal Insufficiency, Chronic , Humans , Female , Aged , Aged, 80 and over , Male , Frailty/epidemiology , Renal Dialysis , Polypharmacy
4.
Nature ; 592(7853): 237-241, 2021 04.
Article in English | MEDLINE | ID: mdl-33828316

ABSTRACT

Magma viscosity strongly controls the style (for example, explosive versus effusive) of a volcanic eruption and thus its hazard potential, but can only be measured during or after an eruption. The identification of precursors indicative of magma viscosity would enable forecasting of the eruption style and the scale of associated hazards1. The unanticipated May 2018 rift intrusion and eruption of Kilauea Volcano, Hawai'i2 displayed exceptional chemical and thermal variability in erupted lavas, leading to unpredictable effusion rates and explosivity. Here, using an integrated analysis of seismicity and magma rheology, we show that the orientation of fault-plane solutions (which indicate a fault's orientation and sense of movement) for earthquakes preceding and accompanying the 2018 eruption indicate a 90-degree local stress-field rotation from background, a phenomenon previously observed only at high-viscosity eruptions3, and never before at Kilauea4-8. Experimentally obtained viscosities for 2018 products and earlier lavas from the Pu'u 'O'o vents tightly constrain the viscosity threshold required for local stress-field reorientation. We argue that rotated fault-plane solutions in earthquake swarms at Kilauea and other volcanoes worldwide provide an early indication that unrest involves magma of heightened viscosity, and thus real-time monitoring of the orientations of fault-plane solutions could provide critical information about the style of an impending eruption. Furthermore, our results provide insight into the fundamental nature of coupled failure and flow in complex multiphase systems.

5.
Nat Commun ; 12(1): 1711, 2021 Mar 17.
Article in English | MEDLINE | ID: mdl-33731713

ABSTRACT

Ferrovolcanism, yet to be directly observed, is the most exotic and poorly understood predicted manifestation of planetary volcanism. Large-scale experiments carried out at the Syracuse Lava Project offer insight into the emplacement dynamics of metallic flows as well as coeval metallic and silicate flows. Here, we find that, under the same environmental conditions, higher-density/lower-viscosity metallic lava moves ten times faster than lower-density/higher-viscosity silicate lava. The overall morphology of the silicate flow is not significantly affected by the co-emplacement of a metallic flow. Rather, the metallic flow is largely decoupled from the silicate flow, occurring mainly in braided channels underneath the silicate flow and as low-relief breakouts from the silicate flow front. Turbulent interactions at the metallic-silicate flow interface result in mingling of the two liquids, preserved as erosional surfaces and sharp contacts. The results have important implications for the interpretation of possible ferrovolcanic landscapes across our solar system.

6.
J Hand Surg Eur Vol ; 40(4): 356-61, 2015 May.
Article in English | MEDLINE | ID: mdl-25524055

ABSTRACT

We present a retrospective study of 107 cases of thumb carpometacarpl joint arthrodesis. The aim of our study was to analyse our population and to compare the outcomes of patients who obtained bone union with the patients who did not. There were no statistical differences in most of the clinical outcomes (DASH score, visual analogue scale, Kapandji test, grip, and key pinch) between the two groups of patients; there were fewer cases of scaphotrapeziotrapezoid arthritis in the group that did not obtain bone union. We conclude that the bone union is not necessary for a good outcome. Level IV of evidence.


Subject(s)
Arthrodesis/adverse effects , Carpometacarpal Joints/surgery , Osteoarthritis/surgery , Trapezium Bone/surgery , Adult , Aged , Carpometacarpal Joints/diagnostic imaging , Carpometacarpal Joints/physiopathology , Female , Fracture Healing , Fractures, Ununited/diagnostic imaging , Fractures, Ununited/etiology , Humans , Male , Middle Aged , Osteoarthritis/diagnostic imaging , Radiography , Recovery of Function , Retrospective Studies , Thumb/diagnostic imaging , Thumb/physiopathology , Thumb/surgery , Trapezium Bone/diagnostic imaging , Trapezium Bone/physiopathology , Treatment Outcome
7.
J Hand Surg Eur Vol ; 38(5): 508-14, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23303835

ABSTRACT

The purpose of this study was to assess the long-term clinical results and morphological changes after tendon ball arthroplasty for advanced Kienböck's disease. Twenty-six patients were reviewed, with a mean follow-up interval of 125 months (range 50-226). At follow-up, mean score on the Disabilities of the Arm, Shoulder, and Hand questionnaire was 7.7 and mean visual analogue scale score for pain was 1. Mean carpal height ratio was significantly reduced with respect to the pre-operative value. On magnetic resonance imaging scans, cartilage damage, synovitis, and erosive or oedematous changes in the bones were detected in most patients. Calcification in the defect filled by the tendon ball was seen in all patients. Narrowing of the radioscaphoid joint and the presence of intercarpal synovitis were negatively associated with clinical outcome. Tendon ball arthroplasty in advanced Kienböck's disease results in long-term satisfactory clinical outcomes, despite widespread changes in the bones and joints within the wrist.


Subject(s)
Arthroplasty/methods , Magnetic Resonance Imaging , Osteonecrosis/pathology , Osteonecrosis/surgery , Adult , Disability Evaluation , Female , Humans , Male , Middle Aged , Pain Measurement , Surveys and Questionnaires , Tomography, X-Ray Computed , Treatment Outcome
8.
J Struct Biol ; 173(2): 241-9, 2011 Feb.
Article in English | MEDLINE | ID: mdl-20850546

ABSTRACT

Shells of adult individuals from two different bivalve families, Hyriopsis cumingii and Diplodon chilensis patagonicus, were studied by Micro-Raman spectroscopy and Focussed Ion Beam-assisted TEM. The shells contain amorphous calcium carbonate in a zone at the interface between the periostracum and the prismatic layer. In this area, the initial prism structures protrude from the inner periostracum layer and it is demonstrated that these structures systematically consist of highly disordered and amorphous calcium carbonate. Within this zone, ordered and disordered areas are intermingled discounting the existence of a crystallization front and favouring models of domainal crystallization processes via so-called mesocrystals. These observations are the first documentation of the use of amorphous calcium carbonate as a precursor phase by adult mollusc species and lend further support to hypotheses postulating widespread use of amorphous phases as building material of skeletal tissue in biology.


Subject(s)
Bivalvia/chemistry , Calcium Carbonate/chemistry , Animals , Bivalvia/ultrastructure , Microscopy, Electron, Transmission , Spectrum Analysis, Raman
9.
J Synchrotron Radiat ; 17(2): 193-201, 2010 Mar.
Article in English | MEDLINE | ID: mdl-20157271

ABSTRACT

X-ray absorption near-edge spectroscopy (XANES) at the Mn K-edge was used to investigate the environment of Mn in situ within the growth increments of the long-lived freshwater bivalve species Diplodon chilensis patagonicus. Single XANES spectra and Mn Kalpha fluorescence distributions were acquired at submillimetre resolution (up to 100 microm x 50 microm), at Mn concentrations below the weight percent range (100-1000 microg g(-1)) in a high Ca matrix. The position and intensity of the pre-edge feature in the shell spectrum resembles best that of the Mn(II)-bearing reference compounds, suggesting that this is the oxidation state of Mn in the bivalve shells. By comparison with the XANES spectra of selected standard compounds, hypotheses about Mn speciation in the shell are also reported. In particular, different factors, such as provenance, ontogenetic age, variable Mn-concentrations or seasonal shell deposition seem not to influence the speciation of the metal in this bivalve species.


Subject(s)
Bivalvia/metabolism , Manganese/chemistry , Animals , Bivalvia/growth & development , Manganese/metabolism , X-Ray Absorption Spectroscopy
10.
Phys Rev E Stat Nonlin Soft Matter Phys ; 80(1 Pt 2): 015302, 2009 Jul.
Article in English | MEDLINE | ID: mdl-19658760

ABSTRACT

Preferential concentration of inertial particles in turbulence is studied numerically by evaluating the Lagrangian compressibility of the particle velocity field using the "full Lagrangian method." This is compared with the "mesoscopic Eulerian particle velocity field" both in a direct numerical simulation of turbulence and in a synthetic flow field. We demonstrate that the Lagrangian method, in contrast to the Eulerian, accurately predicts the compressibility of the particle velocity field even when the latter is characterized by singularities. In particular we use the method to evaluate the growth rates of spatial moments of the particle number density which reflect the fractal structure of segregation and the occurrence of singularities.

11.
Eur Rev Med Pharmacol Sci ; 13(2): 133-9, 2009.
Article in English | MEDLINE | ID: mdl-19499849

ABSTRACT

Carpal Tunnel Syndrome (CTS) is the most common peripheral mononeuropathy; its symptoms and functional limitations significantly penalize the daily activities and quality of life of many people. While surgery is reserved to most severe cases, the earlier stages of disease may be controlled by a pharmacological treatment aimed to "neuroprotection", i.e. to limiting and correcting the nerve damage. Our study was aimed to compare the efficacy of a fixed association of alpha-lipoic acid (ALA) 600 mg/die and gamma-linolenic acid (GLA) 360 mg/die, and a multivitamin B preparation (Vit B6 150 mg, Vit B1 100 mg, Vit B12 500 microg daily) for 90 days in 112 subjects with moderately severe CTS. Demographic, case-history and treatment efficacy data were collected; the Boston questionnaire was administered and the patients were evaluated by Hi-Ob scale and electro-myography. A significant reduction in both symptoms scores and functional impairment (Boston questionnaire) was observed in ALA/GLA group, while the multivitamin group experienced a slight improvement of symptoms and a deterioration of functional scores. Electromyography showed a statistically significant improvement with ALA/GLA, but not with the multivitamin product. The Hi-Ob scale showed significant efficacy of ALA/GLA in improving symptoms and functional impairment, while in the multivitamin group the improvement was significant, but less marked than in the ALA/GLA group. In conclusion, the fixed association of ALA and GLA proved to be a useful tool and may be proposed for controlling symptoms and improving the evolution of CTS, especially in the earlier stages of disease.


Subject(s)
Carpal Tunnel Syndrome/drug therapy , Thioctic Acid/therapeutic use , Vitamin B Complex/therapeutic use , gamma-Linolenic Acid/therapeutic use , Adolescent , Adult , Aged , Aged, 80 and over , Carpal Tunnel Syndrome/physiopathology , Drug Combinations , Electromyography , Female , Humans , Male , Middle Aged , Severity of Illness Index , Surveys and Questionnaires , Thiamine/administration & dosage , Thiamine/therapeutic use , Thioctic Acid/administration & dosage , Vitamin B 12/administration & dosage , Vitamin B 12/therapeutic use , Vitamin B 6/administration & dosage , Vitamin B 6/therapeutic use , Vitamin B Complex/administration & dosage , Young Adult , gamma-Linolenic Acid/administration & dosage
12.
Anal Chim Acta ; 599(2): 177-90, 2007 Sep 19.
Article in English | MEDLINE | ID: mdl-17870280

ABSTRACT

Ten international laboratories participated in an inter-laboratory comparison of a fossil bone composite with the objective of producing a matrix and structure-matched reference material for studies of the bio-mineralization of ancient fossil bone. We report the major and trace element compositions of the fossil bone composite, using in-situ method as well as various wet chemical digestion techniques. For major element concentrations, the intra-laboratory analytical precision (%RSD(r)) ranges from 7 to 18%, with higher percentages for Ti and K. The %RSD(r) are smaller than the inter-laboratory analytical precision (%RSD(R); <15-30%). Trace element concentrations vary by approximately 5 orders of magnitude (0.1 mg kg(-1) for Th to 10,000 mg kg(-1) for Ba). The intra-laboratory analytical precision %RSD(r) varies between 8 and 45%. The reproducibility values (%RSD(R)) range from 13 to <50%, although extreme value >100% was found for the high field strength elements (Hf, Th, Zr, Nb). The rare earth element (REE) concentrations, which vary over 3 orders of magnitude, have %RSD(r) and %RSD(R) values at 8-15% and 20-32%, respectively. However, the REE patterns (which are very important for paleo-environmental, taphonomic and paleo-oceanographic analyses) are much more consistent. These data suggest that the complex and unpredictable nature of the mineralogical and chemical composition of fossil bone makes it difficult to set-up and calibrate analytical instruments using conventional standards, and may result in non-spectral matrix effects. We propose an analytical protocol that can be employed in future inter-laboratory studies to produce a certified fossil bone geochemical standard.


Subject(s)
Bone and Bones/chemistry , Fossils , Mass Spectrometry/methods , Animals , Apatites/analysis , Lasers , Metals, Rare Earth/analysis , Organophosphates/analysis , Reference Standards , Reproducibility of Results , Trace Elements/analysis
13.
Theor Appl Genet ; 109(3): 618-29, 2004 Aug.
Article in English | MEDLINE | ID: mdl-15179549

ABSTRACT

The improvement of early vigour is crucial for the adaptation of maize (Zea mays L.) to the climatic conditions of central Europe and the northern Mediterranean, where early sowing is an important strategy for avoiding the effect of summer drought. The objectives of this study were to identify quantitative trait loci (QTL) controlling cold-related traits and to investigate the relationships among them. A set of 168 F2:4 families of the Lo964 x Lo1016 cross was grown in a sand-vermiculite substrate at 15/13 degrees C (day/night) until the one-leaf stage. Twenty QTL were identified for the four shoot and two seed traits examined. Analysis of root weight and digital measurements of the length and diameter of primary and seminal roots led to the identification of 40 QTL. The operating efficiency of photosystem II (PhiPSII) was related to seedling dry weight at both the phenotypic and genetic level (r = 0.46, two matching loci, respectively) but was not related to root traits. Cluster analysis and QTL association revealed that the different root traits were largely independently inherited and that root lengths and diameters were mostly negatively correlated. The major QTL for root traits detected in an earlier study in hydroponics were confirmed in this study. The length of the primary lateral roots was negatively associated with the germination index (r = -0.38, two matching loci). Therefore, we found a large number of independently inherited loci suitable for the improvement of early seedling growth through better seed vigour and/or a higher rate of photosynthesis.


Subject(s)
Cold Temperature , Phenotype , Plant Roots/physiology , Plant Shoots/physiology , Zea mays/genetics , Agriculture/methods , Cluster Analysis , Crosses, Genetic , Europe , Photosystem II Protein Complex/genetics , Photosystem II Protein Complex/physiology , Plant Roots/genetics , Plant Shoots/genetics , Quantitative Trait Loci/genetics , Zea mays/physiology
14.
Planta Med ; 64(5): 431-7, 1998 Jun.
Article in English | MEDLINE | ID: mdl-9690345

ABSTRACT

Agronomical and biochemical parameters of seven Hypericum perforatum (St. John's wort) accessions grown at three experimental sites in Switzerland were followed over a two year period (1995-1996). Significant effects of environmental (= site) and genetic factors (= accession) on flowering dates, plant length, and plant dry matter production (= plant yield) were observed in both years; rankings of sites and accessions with regard to plant yield were similar in both years despite the fact that the first year crop contributed only a minor part to the overall yield of both years together. Maximum dry matter production per year reached 159 dt/ha for the total plant and 54 dt/ha for the flowering segment (i.e. the pharmaceutically relevant, upper segment of the plants comprising the majority of flowers). HPLC analysis of the constituents covered eight secondary metabolites (amentoflavone, biapigenin, hyperforin, hypericin, hyperosid, pseudohypericin, quercetin, rutin). Generally, secondary metabolite contents were significantly lower in the first year of cultivation ranging from 12% (hyperosid) to 83% (hyperforin) of the contents measured in the 1996-crop. Significant genetic effects on the production of all tested secondary metabolites (except biapigenin) were observed in 1996 whereas environmental effects appeared to be less distinct (except for amentoflavone and pseudohypericin). In conclusion, genetic factors strongly affected plant yield as well as secondary metabolite content in H. perforatum cultivation; the availability of genetically superior plant material next to improved agrotechnological methods therefore is supposed to become a key factor for successful future field production.


Subject(s)
Plants, Medicinal/genetics , Chromatography, High Pressure Liquid , Plants, Medicinal/chemistry , Plants, Medicinal/growth & development
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