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Catalogo Della Libreria Del Fu Cavaliere Giuseppe Bossi Pittore Milanese
No full textCATALOGO DELLA LIBRERIA DEL FU CAVALIERE GIUSEPPE BOSSI PITTORE MILANESE
Catalogo Della Libreria Del Fu Cavaliere Giuseppe Bossi Pittore Milanese ([1]r)
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Sucrose- and H+-dependent charge movements associated with the gating of sucrose transporter ZmSUT1
No full textBackground: In contrast to man the majority of higher plants use sucrose as mobile carbohydrate. Accordingly proton-driven sucrose transporters are crucial for cell-to-cell and long-distance distribution within the plant body. Generally very negative plant membrane potentials and the ability to accumulate sucrose quantities of more than 1 M document that plants must have evolved transporters with unique structural and functional features.
Methodology/Principal Findings: To unravel the functional properties of one specific high capacity plasma membrane sucrose transporter in detail, we expressed the sucrose/H+ co-transporter from maize ZmSUT1 in Xenopus oocytes. Application of sucrose in an acidic pH environment elicited inward proton currents. Interestingly the sucrose-dependent H+ transport was associated with a decrease in membrane capacitance (Cm). In addition to sucrose Cm was modulated by the membrane potential and external protons. In order to explore the molecular mechanism underlying these Cm changes, presteady-state currents (Ipre) of ZmSUT1 transport were analyzed. Decay of Ipre could be best fitted by double exponentials. When plotted against the voltage the charge Q, associated to Ipre, was dependent on sucrose and protons. The mathematical derivative of the charge Q versus voltage was well in line with the observed Cm changes. Based on these parameters a turnover rate of 500 molecules sucrose/s was calculated. In contrast to gating currents of voltage dependent-potassium channels the analysis of ZmSUT1-derived presteady-state currents in the absence of sucrose (I = Q/τ) was sufficient to predict ZmSUT1 transport-associated currents.
Conclusions: Taken together our results indicate that in the absence of sucrose, ‘trapped’ protons move back and forth between an outer and an inner site within the transmembrane domains of ZmSUT1. This movement of protons in the electric field of the membrane gives rise to the presteady-state currents and in turn to Cm changes. Upon application of external sucrose, protons can pass the membrane turning presteady-state into transport currents
Electrogenic Kinetics of a Mammalian Intestinal Type IIb Na+/Pi Cotransporter
No full textThe kinetics of a type IIb Na(+)-coupled inorganic phosphate (Pi) cotransporter (NaPi-IIb) cloned from mouse small intestine were studied using the two-electrode voltage clamp applied to Xenopus oocytes. In the steady state, mouse NaPi-IIb showed a curvilinear I-V relationship, with rate-limiting behavior only for depolarizing potentials. The Pi dose dependence was Michaelian, with an apparent affinity constant for Pi (Km(pi)) of 10 +/- 1 microM: at -60 mV. Unlike for rat NaPi-IIa, (Km(pi)) increased with membrane hyperpolarization, as reported for human NaPi-IIa, flounder NaPi-IIb and zebrafish NaPi-IIb2. The apparent affinity constant for Na(+) (Km(na)) was 23 +/- 1 mM: at -60 mV, and the Na(+) activation was cooperative with a Hill coefficient of approximately 2. Pre-steady-state currents were documented in the absence of Pi and showed a strong dependence on external Na(+). The hyperpolarizing shift of the charge distribution midpoint potential was 65 mV/log[Na]. Approximately half the moveable charge was attributable to the empty carrier. A comparison of the voltage dependence of steady-state Pi-induced current and pre-steady-state charge movement indicated that for -120 mV <or= V <or= 0 mV the voltage dependence of the empty carrier was the main determinant of the curvilinear steady-state cotransport characteristic. External protons partially inhibited NaPi-IIb steady-state activity, independent of the titration of mono- and divalent Pi, and immobilized pre-steady-state charge movements associated with the first Na(+) binding step
Switchable fluorescent and solvatochromic molecular probes based on 4-amino-N-methylphthalimide and a photochromic diarylethene.
No full textNew fluorescent photochromic compounds (1-H and 1-Boc)have been synthesized and characterized in different solvents.The fluorescence emission can be switched “on” and“off” with visible light and UV, respectively, by means of thephotochromic reaction. The emission wavelength and efficiencystrongly depend on the polarity of the solvent. Thecompounds show a positive solvatochromic effect in theemission maxima, and their fluorescence quantum yield decreasesas the solvent’s polarity increases (from cyclohexaneto dioxane). In solvents more polar than dioxane the emissionis too weak and therefore undetectable, and thus 1-H and 1-Boc behave as “normal” photochromic compounds. The photochromic reaction is also sensitive to the environment. A decreaseof more than an order of magnitude was found for thequantum yield of the colouring reaction (ΦOFCF) for 1-H inethanol compared with cyclohexane, and an about threefolddecrease in ΦOFCF was observed for the compound 1-Bocin polar solvents (compared with apolar solvents). For bothcompounds the ring-opening reaction was found not to dependenton the solvent. The novel fluorescent molecularswitches 1-H and 1-Boc are able to probe the polarity of theirmicroenvironment.Fil: Yan, Sergey F.. Max Planck Institute for Biophysical Chemistry; AlemaniaFil: Belov, Vladimir N.. Max Planck Institute for Biophysical Chemistry; AlemaniaFil: Bossi, Mariano Luis. Max Planck Institute for Biophysical Chemistry; Alemania. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; ArgentinaFil: Hell, Stefan W.. Max Planck Institute for Biophysical Chemistry; Alemani
Arm Disability in Patients on Hemodialysis
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Arm Disability in Patients on Hemodialysis
Author(s): Toffola, ED (Toffola, Elena Dalla)1; Petrucci, L (Petrucci, Lucia); Mazzacane, B (Mazzacane, Bruno); Klersy, C (Klersy, Catherine)2; Villa, G (Villa, Giuseppe); Bossi, D (Bossi, Daniela)3; Bejor, M (Bejor, Maurizio)1
Source: DIALYSIS & TRANSPLANTATION Volume: 39 Issue: 3 Pages: 100-+ DOI: 10.1002/dat.20418 Published: MAR 2010
Times Cited: 0 (from Web of Science)
Cited References: 29 [ view related records ] Citation Map
Abstract: INTRODUCTION: End-stage renal disease patients on hemodialysis (HD) often present osteoarticular and musculoskeletal complications related both to chronic renal disease as well as to chronic dialysis. The aim of the present study was to assess the degree of upper-limb disability, and its determinants, in a group of patients on chronic HD to determine functional capacity and the need for rehabilitative treatment.
MATERIALS AND METHODS: We studied 97 HD patients (46 male, 51 female) with a mean age of 64.4 years, and 51 healthy controls. The Disabilities of the Arm, Shoulder, and Hand (DASH) Outcome Measure was used to clinically assess degree of disability as well as finger function and movement.
RESULTS: For study purposes, patients were divided into 3 groups according to the duration of dialysis: 10 years. The median DASH score was 9.5 (interquartile range [IQR]: 3.4-24.1) in the entire population. However, it differed significantly in the 3 dialysis groups with scores of 5.2 (IQR: 2.6-18.1), 14.7 (3.4-23.7), and 37.5 (9.5-73.3) in the 10 year groups, respectively (p < .001). Additionally, disability correlated with shoulder and hand pain and with finger stiffness. Moreover, patients on dialysis for more than 10 years were affected by pain involving several upper limb joints. All patients who worked had a DASH score lower than 20. The median DASH score was 2.6 (IQR: 0.9-5.2) in the control group.
CONCLUSION: Duration of dialysis is associated with progressive disability. Thus, early rehabilitation programs are recommended in patients who are expected to undergo long-term dialysi
On the Cooling Effect of an Air Jet Along the Surface of a Cylinder
No full textHeat transfer of slot jets of air impinging on the surface of a circular cylinder by forced convection has been investigated. The cylinder has a diameter of D=10 mm and the slot jet has a height of S=5 mm. The thermocouples, located along the surface of the cylinder, at various angles from the impinging point, allow the evaluation of the local convective heat transfer coefficients. The experiments have been performed for a Reynolds number of the impinging air ranging from Re=4000 to Re=20000. The influence of the distance H, between the exit of the slot jet and the cylinder, has been investigated in the range of H/S, H/S=2–10. The local Nusselt number is a function of the H/S ratio and of the angle from the front impinging point. It is also dependent on the Reynolds number
Optimal Slot Height in the Jet Cooling of a Circular Cylinder
No full textExperimental results are presented for heat transfer cooling of an electrically heated circular cylinder, of diameter D=10 mm, by a slot jet, of height S=2.5 mm, i.e. with D/S=4. Mean and local Nusselt numbers are presented versus the Reynolds numbers, the distance of the cylinder from the slot exit, H, and the angle from the impinging point. Mean Nusselt numbers, defined according to the cylinder diameter, D, are higher than the values in an infinite flow. The maximum mean Nusselt number is measured when the cylinder is set at a distance H, from the slot exit, such that H/S=8. The minimum local Nusselt number is measured at an angle of 180° from the impinging point, i.e. on the rear of the cylinder. Comparisons have been done among the mean Nusselt numbers of this work and previous experimental results of the same authors, carried out with diameter to slot height ratios equal to D/S=1 and 2. The conclusion is that the mean Nusselt number, defined as , is higher for D/S=4, versus the Reynolds number, defined as ReD=WD/ν. On the contrary, the mean Nusselt number, defined on the basis of the slot height, , has similar values, for the different slot heights, versus the Reynolds number, defined as ReS=WS/ν, with the trend of higher results for the slot with D/S=2
Big data for a rare disease: complexity and usefulness
No full textIntroduction: Cystic Fibrosis (CF) is a genetic rare disease, but the concerted actions of medical personnel, researchers and patients allowed the institution of the European Cystic Fibrosis Society Patient Registry (ECFSPR) to collect information on a large number of patients from different European countries in a common format [1].
Objectives: The aim is to show the complexity of the ECFSPR that deals with the management and analysis of a large amount of data and the usefulness of such information for the care of CF patients.
Methods: The ECFSPR collects information on CF European patients (diagnosis, genetics, lung function, growth, complications, microbiology, therapy and transplantation) collated annually by national CF registries and individual CF centres since 2003 (cross-sectional data till 2007, longitudinal data from 2008): it includes data of about 30,000 patients from 22 countries [2]. In order to identify and solve problems, a team that daily works on the ECFSPR was set up ‘service desk’ together with an executive committee and a steering group composed by national representatives that define the major activities of the ECFSPR (data protection legislation, use of data). The research activity is supervised by a scientific committee that identifies major research areas and approves the external data requests.
Results: The critical aspects encountered in the institution of the ECFSPR (definition of the population under study, of inclusion criteria, of what to measure and how) were dealt with a definition group whose members have different expertise and a long experience in CF in creation of healthcare databases.
Assessment of whether patients registered meet the inclusion criteria, data quality controls and data management, handling of missing data, maintaining patient confidentiality and dissemination of data are activities that need to be carried out daily. The assessment of the compliance of the inclusion criteria is responsibility of the national CF registries and individual CF centres since the information sent to ECFSPR are not enough to decide if patients can be included or not. The experience and the expertise of each member of the data quality control group allowed creation of a complete and shared list of data quality controls that are performed by all national registry data managers before sending the data to the ECFSPR. The data management and the handling of missing data are the main activities of the working group: from the uploading of the data to the freezing of the database through the process of correction of the inconsistencies found in the data, the registry coordinator, the service desk and the statistician work in close contact with the national and centres representatives. Maintaining patients confidentiality is one of the crucial aspects in order to reassure patients that decide to give the consent of the use of their data. With a clear language, the ECFSPR gives the necessary information to the patient in order to ensure that security measures meet data protection legislation and are updated if necessary.
The availability of the information on a large number of patients affected by a rare disease allows the study of the epidemiology of the CF [3, 4], also focusing on CF atypical patients. The availability of this information allows also the identification of group of patients eligible for clinical trials that, otherwise, could not be carried out if only a small number of patients were involved. Pharmacovigilance is a potential aspect that can be investigated in order to record adverse events following the use of treatments.
Monitoring care services in the European countries and, for future, planning adequate CF centres are other activities that the availability of a large amount of information makes possible [5]. Giving an answer to a clinical request needs to take into account that these are registry data and they are not collected with ad hoc studies. However, studies on registry data can have an explorative nature and ad hoc studies can be carried out starting from the first results obtained by the ECFSPR.
Conclusions: The complexity of the ECFSPR is magnified by the international setting: agreement on all the aspects of the involvement into the ECFSPR is not easily reached in a short time. However the usefulness of information for the care of CF patients that can be obtained from a European registry for a rare disease is inestimable, therefore all the difficulties are faced and overcome.
References
[1] Viviani L, Zolin A, Mehta A, Olesen HV. The European Cystic Fibrosis Society Patient Registry: valuable lessons learned on how to sustain a disease registry. Orphanet J Rare Dis. 2014 Jun 7;9(1):81. doi:10.1186/1750-1172-9-81.
[2] Zolin A, McKone EF, van Rens J et al. ECFSPR Annual Report 2010, 2014, accessed on 15th May 2015.
[3] Kerem E, Viviani L, Zolin A, MacNeill S, Hatziagorou E, Ellemunter H, Drevinek P, Gulmans V, Krivec U, Olesen H on behalf of the ECFS Patient Registry Steering Group. Modifiers of pulmonary function in cystic fibrosis: analysis of the data of the ECFS Patient Registry. Eur Respir J. 2014 Jan;43(1):125-33. doi: 10.1183/09031936.00166412.
[4] De Boeck K, Zolin A, Cuppens H, Olesen HV, Viviani L. The relative frequency of CFTR mutation classes in European patients with cystic fibrosis. J Cyst Fibros. 2014 Jul;13(4):403-9. doi: 10.1016/j.jcf.2013.12.003.
[5] Burgel PR, Bellis G, Olesen HV, Viviani L, Zolin A, Blasi F, Elborn JS; ERS/ECFS Task Force on The Provision of Care for Adults with Cystic Fibrosis in Europe. Future trends in cystic fibrosis demography in 34 European countries. Eur Respir J. 2015 Mar 18. pii: ERJ-01963-2014
Recension del Libro de Laura Bossi, Las fronteras de la muerte
No full textRecensiónLo que la autora se esfuerza por mostrar es el conjunto de dificultades éticas que implican la medicalización
de la muerte. La tesis principal defendida por Laura Bossi es la de la crítica de la progresiva medicalización de
la muerte, que gradualmente se ha inclinado hacia una lógica pragmática y utilitaria. Al final, terminó venciendo
el poder tecnocrático de la nueva biología del órgano que quiere, mediante los poderes de la tecnología,
borrar la muerte o, mejor, curarlaWhat the author strives to show is the set of ethical difficulties that involve the medicalization of death. The main thesis defended by Laura Bossi is the criticism of the progressive medicalization of death, which has gradually leaned towards a pragmatic and utilitarian logic. Finally, it ended up winning the technocratic power of the new biology of the organ that wants, through the powers of technology, erase death or, better, cure itinfo:eu-repo/semantics/publishedVersio
Surface imprinted beads for the recognition of human serum albumin
No full textThe synthesis of poly-aminophenylboronic acid (ABPA) imprinted beads for the
recognition of the protein human serum albumin (HSA) is reported. In order to
create homogeneous recognition sites, covalent immobilisation of the template
HSA was exploited. The resulting imprinted beads were selective for HSA. The
indirect imprinting factor (IF) calculated from supernatant was 1.6 and the
direct IF, evaluated from the protein recovered from the beads, was 1.9. The
binding capacity was 1.4 mg/g, which is comparable to commercially available
affinity materials. The specificity of the HSA recognition was evaluated with
competitive experiments, indicating a molar ratio 4.5/1 of competitor was
necessary to displace half of the bound HSA. The recognition and binding of the
imprinted beads was also tested with a complex sample, human serum and targeted
removal of HSA without a loss of the other protein components was demonstrated.
The easy preparation protocol of derivatised beads and a good protein
recognition properties make the approach an attractive solution to analytical
and bio-analytical problems in the field of biotechnology
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