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1.
Immunol Lett ; 262: 7-17, 2023 10.
Article in English | MEDLINE | ID: mdl-37634711

ABSTRACT

This study was designed to characterize mice bone marrow (BM) and bone marrow-derived dendritic cells (BMDC) and to compare the surface markers expression and inflammatory cytokine liberation in response to LPS and Bothrops jararacussu venom (BjV) stimulation. Typical morphology was observed in BM and BMDCs from the 4th up to the 8th day of culture using recombinant mouse GM-CSF and IL-4. A high basal level of MHC-II, CD1d, CD83, CD11c, CD80, and low CD86 was expressed by BM cells. After stimulation with GM-CSF/IL-4 for BMDCs differentiation, the BM cells differentiated into BMDCs presented MHC-II, CD1d, CD83, CD11c, CD86, and CD80 expression on the 4th - 8th day accompanied with high levels of TNF-α liberated. The difference between the surface markers' expression was observed in this time course in which CD1d, CD11c, and CD80 remained in high levels of expression, while MHC-II and CD83 showed moderate expression during the differentiation period. Also, cytokines liberation was monitored over the period of the BMDCs culture, and on the 6th day, low levels of IL-6 and IL-1ß were found, while high levels of TNF-α on the 4th and 8th days, both of which contributed to the maturity of the BMDCs. Maturation of DCs with LPS showed significant upregulation of surface markers (MHC-II, CD1d, CD83, CD86, CD80) and pro-inflammatory cytokines (IL-1ß, IL-6, TNF-α) liberation. On the other hand, BjV induced a decrease in CD1d, CD11c, CD83, and CD86 expression in mature BMDCs which was not observed when LPS was used to stimulate BMDCs which probably induces impairment in T-cell activation.


Subject(s)
Granulocyte-Macrophage Colony-Stimulating Factor , Tumor Necrosis Factor-alpha , Animals , Mice , Granulocyte-Macrophage Colony-Stimulating Factor/pharmacology , Bone Marrow , Interleukin-4 , Interleukin-6 , Lipopolysaccharides , Snake Venoms , Cytokines , Dendritic Cells
2.
Toxicon ; 185: 156-163, 2020 Oct 15.
Article in English | MEDLINE | ID: mdl-32702355

ABSTRACT

Snakebite is a universally neglected public health problem. It victimizes approximately 2.5 million people annually and kills around 125 thousand. In Brazil, the Bothrops genus is responsible for 87% of the envenoming. The species Bothrops erythromelas is endemic in the northeast region. Its venom induces local haemorrhage, coagulopathy, oedema, and necrosis and can lead to permanent disability or death. The in vitro effects of Bothrops erythromelas venom (BeV) on thioglycollate-elicited macrophages were investigated in this study. At non-cytotoxic concentrations, BeV did not interfere with the adhesion and detachment of thioglycollate-elicited macrophages. However, BeV induced lipid body formation and the activation of respiratory burst and TNF-α, but not IL-1ß and IL-6. The study aimed to extend the knowledge on the mechanism of action of BeV and its contribution toward a better characterisation of macrophage functionality under the action of Bothrops venom.


Subject(s)
Bothrops , Crotalid Venoms/toxicity , Animals , Brazil , Edema , Leukocyte Count , Macrophages/drug effects , Mice , Snake Bites
3.
Pulmonology ; 26(1): 10-17, 2020.
Article in English | MEDLINE | ID: mdl-31630986

ABSTRACT

OBJECTIVE: The main aim of the study was to evaluate the efficacy and safety profile of Nivolumab, an immune-checkpoint-inhibitor antibody, in advanced, previously treated, Non-Small Cell Lung Cancer (NSCLC) patients, in a real world setting. METHODS: We performed a retrospective, multicentre data analysis of patients who were included in the Portuguese Nivolumab Expanded Access Program (EAP). Eligibility criteria included histologically or citologically confirmed NSCLC, stage IIIB and IV, evaluable disease, sufficient organ function and at least one prior line of chemotherapy. The endpoints included Overall Response Rate (ORR), Disease Control Rate (DCR), Progression Free Survival (PFS) and Overall Survival (OS). Safety analysis was performed with the National Cancer Institute Common Terminology Criteria for Adverse Events (CTCAE), version 4.0, and immune-related Adverse Events (irAEs) were treated according to protocol treatment guidelines. Tumour response was assessed using the Response Evaluation Criteria in Solid Tumours (RECIST) version 1.1. Data was analysed using SPSS, version 21.0 (IBM Statistics). RESULTS: From June 2015 to December 2016, a total of 229 patients with advanced NSCLC were enrolled at 30 Portuguese centres. Clinical data were collected up to the end of July 2018. The baseline median age was 64 years (range 37-83) and the majority of patients were males (70.3%) and former/current smokers (69.4%). Patients with non-squamous histology predominated (88.1%), and 67.6% of the patients had received 2 or more prior lines of chemotherapy. Out of 229 patients, data was available for 219 patients (3 patients did not start treatment, while data was unavailable in 7 patients); of the 219 patients, 15.5% were not evaluated for radiological tumour assessment, 1.4% had complete response (CR), 21% partial response (PR), 31% stable disease (SD) and 31.1% progressive disease (PD). Thus, the ORR was 22.4% and DCR was 53.4% in this population. At the time of survival analysis the median PFS was 4.91 months (95% CI, 3.89-6.11) and median OS was 13.21 months (95% CI, 9.89-16.53). The safety profile was in line with clinical trial data. CONCLUSIONS: Efficacy and safety results observed in this retrospective analysis were consistent with observations reported in clinical trials and from other centres.


Subject(s)
Carcinoma, Non-Small-Cell Lung/drug therapy , Lung Neoplasms/drug therapy , Nivolumab/therapeutic use , Adult , Aged , Aged, 80 and over , Antineoplastic Agents, Immunological/therapeutic use , Carcinoma, Non-Small-Cell Lung/diagnosis , Carcinoma, Non-Small-Cell Lung/epidemiology , Female , Humans , Incidence , Lung Neoplasms/diagnosis , Lung Neoplasms/epidemiology , Male , Middle Aged , Portugal/epidemiology , Progression-Free Survival , Retrospective Studies , Survival Rate/trends , Treatment Outcome
5.
Int J Organ Transplant Med ; 10(4): 188-190, 2019.
Article in English | MEDLINE | ID: mdl-33312464

ABSTRACT

Anemia is a common finding after kidney transplantation (KT). Herein, we present a 34-year-old man who received a deceased-donor KT in 2017. Induction immunosuppression therapy consisted of thymoglobulin, tacrolimus (TAC) and methylprednisolone; the maintenance therapy included mycophenolate (MMF) 500 + 500 mg, TAC 4 + 4 mg and prednisolone (PD) 5 mg. One year after KT, he progressively developed dyspnea and fatigue. Laboratory exams revealed hypochromic microcytic anemia unresponsive to increasing doses of darbepoetin. Upper endoscopy and colonoscopy were normal. Bone marrow examination revealed erythroid hyperplasia with numerous proerythroblasts. Serology and viral load for human parvovirus B19 were both positive. Immunosuppression was reduced; he was treated with immunoglobulin. After one week, anemia improved. After 2 months the patient remained asymptomatic with stable hemoglobin. Although rare, PVB19 infection is a clinically significant infection that often presents as aplastic anemia in the post-transplantation period.

6.
HIV Med ; 20(2): 77-87, 2019 02.
Article in English | MEDLINE | ID: mdl-30411475

ABSTRACT

Acute kidney injury (AKI) is characterized by a rapid decline of renal function associated with worse outcomes. The purpose of the authors is to perform a critical review of the incidence, risk factors, pathogenesis and outcome of AKI in HIV-infected patients. Human immunodeficiency virus (HIV)-infected patients have an increased risk of developing AKI, to which contribute both HIV-dependent and HIV-independent factors as well as the nephrotoxicity of drugs used. The increased risk of AKI in HIV-infected patients and its negative impact on prognosis highlights the need for identification of patients at risk, creation of prevention strategies and management. HIV-infected patients have an increased risk of developing AKI, to which both HIV-dependent and HIV-independent factors contribute, as well as the nephrotoxicity of drugs used. The increased risk of AKI in HIV-infected patients and its negative impact on prognosis highlight the need for identification of patients at risk, creation of prevention strategies and management.


Subject(s)
Acute Kidney Injury/epidemiology , Anti-Retroviral Agents/adverse effects , HIV Infections/drug therapy , Acute Kidney Injury/etiology , Anti-Retroviral Agents/therapeutic use , HIV Infections/complications , Humans , Incidence , Prognosis , Risk Factors
7.
Eur J Pharm Biopharm ; 128: 36-47, 2018 Jul.
Article in English | MEDLINE | ID: mdl-29673869

ABSTRACT

The present study aims at acquiring an in-depth process knowledge about a twin-screw granulation and fluid bed drying process performed on the commercially available continuous line. Batch Statistical Process Monitoring (BSPM) principles are used to describe and monitor the variables with a relevant time-related trajectory. The continuous granulator operates in a truly continuous manner and variables logged by this unit do not present time-relevant features. On the other hand, the fluid bed dryer is divided in six identical cells, which are sequentially filled and discharged, ensuring a continuous flow of material. Multiple variables logged at the dryer and subsequent product control unit, present time-relevant features. A profound analysis of these variables logged during normal operation, as well as an in-depth description of the startup period of the different units, were achieved. The BSPM concepts allows to monitor the time relevant variables of this continuous manufacturing line, to detect and diagnose deviations from normal operation and assign possible causes for the disturbances.


Subject(s)
Chemistry, Pharmaceutical/methods , Desiccation/methods , Drug Compounding/methods , Chemistry, Pharmaceutical/instrumentation , Desiccation/instrumentation , Drug Compounding/instrumentation , Multivariate Analysis , Particle Size , Temperature
8.
Int J Pharm ; 528(1-2): 242-252, 2017 Aug 07.
Article in English | MEDLINE | ID: mdl-28583334

ABSTRACT

A multivariate statistical process control (MSPC) strategy was developed for the monitoring of the ConsiGma™-25 continuous tablet manufacturing line. Thirty-five logged variables encompassing three major units, being a twin screw high shear granulator, a fluid bed dryer and a product control unit, were used to monitor the process. The MSPC strategy was based on principal component analysis of data acquired under normal operating conditions using a series of four process runs. Runs with imposed disturbances in the dryer air flow and temperature, in the granulator barrel temperature, speed and liquid mass flow and in the powder dosing unit mass flow were utilized to evaluate the model's monitoring performance. The impact of the imposed deviations to the process continuity was also evaluated using Hotelling's T2 and Q residuals statistics control charts. The influence of the individual process variables was assessed by analyzing contribution plots at specific time points. Results show that the imposed disturbances were all detected in both control charts. Overall, the MSPC strategy was successfully developed and applied. Additionally, deviations not associated with the imposed changes were detected, mainly in the granulator barrel temperature control.


Subject(s)
Technology, Pharmaceutical , Chemistry, Pharmaceutical , Particle Size , Powders , Tablets , Temperature
9.
Eur J Clin Microbiol Infect Dis ; 36(2): 379-386, 2017 Feb.
Article in English | MEDLINE | ID: mdl-27812805

ABSTRACT

The establishment of matrix-assisted laser desorption time-of-flight mass spectrometry (MALDI-TOF MS) in routine microbial identification boosted many developments towards high-throughput applications, including bacterial typing. However, results are still controversial for different bacterial species. We aim to evaluate the suitability of MALDI-TOF MS for typing clinically relevant multidrug resistant (MDR) Klebsiella pneumoniae subsp. pneumoniae clones using routine conditions and a previously validated chemometric analysis workflow. Mass spectra of 83 K. pneumoniae clinical isolates representing major human MDR clones [11 sequence types (STs), 22 PFGE-types] recovered in Portugal and Spain during outbreaks and non-outbreak situations (2003-2012) were obtained from cell extracts (CE) and intact cells (IC), and analysed with different chemometric tools. We observed a highly consistent peak pattern among isolates from different clones either with CE or IC, suggesting a high degree of conservation of biomolecules analysed (a large part corresponding to ribosomal proteins). Moreover, the low degree of agreement between MALDI-TOF MS and other methods (from 34.9 % to 43.4 % of correct assignments for CE and from 40.8 % to 70.1 % for IC) corroborates the low discriminatory potential of the technique at infraspecies level. Our results suggest a low discriminatory power of MALDI-TOF MS for clinically relevant MDR K. pneumoniae clones and highlight the need of developing tools for high-resolution typing in this species.


Subject(s)
Bacterial Typing Techniques/methods , Klebsiella pneumoniae/chemistry , Klebsiella pneumoniae/classification , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods , Humans , Klebsiella Infections/microbiology , Portugal , Spain
10.
Bone Marrow Transplant ; 51(6): 755-62, 2016 Jun.
Article in English | MEDLINE | ID: mdl-26855155

ABSTRACT

Acute kidney injury (AKI) is highly prevalent whether the patients undergo myeloablative or non-myeloablative hematopoietic cell transplantation (HCT); however, the pathogenesis and risk factors leading to AKI can differ between the two. The prognosis of AKI in patients receiving HCT is poor. In fact, AKI following HCT is associated not only with increased short- and long-term mortality, but also with progression to chronic kidney disease. Herein, the authors provide a comprehensive and up-to-date review of the definition and diagnosis, as well as of the incidence, pathogenesis and outcome of AKI in patients undergoing HCT, centering on the differences between myeloablative and non-myeloablative regimens.


Subject(s)
Acute Kidney Injury/diagnosis , Acute Kidney Injury/etiology , Hematopoietic Stem Cell Transplantation/adverse effects , Acute Kidney Injury/chemically induced , Disease Progression , Hematopoietic Stem Cell Transplantation/methods , Humans , Myeloablative Agonists/therapeutic use , Prognosis , Risk Factors , Treatment Outcome
11.
J Ethnopharmacol ; 164: 120-8, 2015 Apr 22.
Article in English | MEDLINE | ID: mdl-25683301

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: Caatinga is highly influenced by its seasonality. This species is endemic in the northeastern region, which is rich in plants with pharmacological potential. Many of these plants are used by the population and some of them have confirmed pharmacological properties. Mimosa caesalpiniifolia Benth. (Mimosaceae) is a native plant from northeastern Brazil׳s caatinga, popularly known as sabiá and cascudo. The tea from the inflorescence of this species is used by the population of the semi-arid for the treatment of hypertension, and the utilization of the plant bark for the staunching of bleedings and wound washing in order to prevent inflammation; also, the ingestion of the bark infusion is used in the treatment of bronchitis. However, its pharmacological effects and mechanisms of action have not yet been studied. The aim of the present study was to determine the effect of the ethanolic extract of M. caesalpiniifolia on the cardiovascular system in rats. MATERIAL AND METHODS: In a study for the assessment of the hypotensive effect of the extract, the polyethylene catheters were inserted in the aorta artery and inferior vena cava for the measurement of the arterial pressure and heart rate. When intragastric administration was performed, only one catheter was implanted in the abdominal aorta. In studies for the vasorelaxant activity, mesenteric arterial rings (1-2mm) were used: they were kept in Tyrode׳s solution (95% O2 and 5% CO2) and submitted to tension of 0.75 g/f for 1h. The results were expressed as mean ± S.E.M., significant to the values of p<0.05. RESULTS: The administration of the doses through venous pathway (6.25; 12.5 and 25mg/kg, i.v.) promoted hypotension followed by bradycardia in the higher doses. The pre-treatment with atropine (2mg/kg, i.v.) interrupted both the hypotension and the bradycardia; with hexamethonium, hypotension was reverted and bradycardia was attenuated. While the administration of tea/flowers (25mg/kg i.v.) also promoted a following section of hypotension, a slight increase in heart rate was observed. When administered orally, MC-EtOH/flowers (100mg/kg, v.o.) promoted a decrease in the arterial pressure from 90 min on, without a significant alteration in the heart rate in relation to the control. In the in vitro study, a pharmacological trial was performed with the extracts obtained from parts of the species M. caesalpiifolia (leaves, bark, fruit and inflorescences). Among all extracts tested, the ethanolic extract from the inflorescences (MC-EtOH/flowers) presented higher vasorelaxant potency in relation to the other parts of the plant. Henceforth, MC-EtOH/flowers was used in the sequence. In mesenteric preparations pre-contracted with phenylephrine (10(-5)M), the MC-EtOH/flowers (0.1-750 µg/ml) promoted vasorelaxant effect regardless of the vascular endothelium. MC-EtOH/flowers inhibited the contractions induced by the cumulative addition of phenylephrine (10(-9)-10(-5)mol/l) or CaCl2 (10(-6)-3 × 10(-2)M), in a concentration-dependent way. In contractions induced by S(-)Bay K 8644, a Cav-L activator, the MC-EtOH/flowers promoted concentration-dependent relaxation, corroborating previous results. CONCLUSION: The tea of flowers of M. caesalpiniifolia promotes hypotension and tachycardia, whereas ethanolic extract (MC-EtOH) promotes hypotension and bradycardia involving the participation of the muscarinic and ganglionic pathways, as well as vasorelaxant action involving the Ca(2+) influx inhibition blockade.


Subject(s)
Hypotension/chemically induced , Mimosa , Plant Extracts/pharmacology , Vasodilator Agents/pharmacology , Animals , Arterial Pressure/drug effects , Ethanol/chemistry , Flowers , Heart Rate/drug effects , Male , Mesenteric Arteries/drug effects , Mesenteric Arteries/physiology , Plant Bark , Plant Leaves , Plant Roots , Rats, Wistar , Solvents/chemistry
12.
Phys Rev Lett ; 111(2): 021301, 2013 Jul 12.
Article in English | MEDLINE | ID: mdl-23889382

ABSTRACT

We present new experimental constraints on the elastic, spin-dependent WIMP-nucleon cross section using recent data from the XENON100 experiment, operated in the Laboratori Nazionali del Gran Sasso in Italy. An analysis of 224.6 live days×34 kg of exposure acquired during 2011 and 2012 revealed no excess signal due to axial-vector WIMP interactions with 129Xe and 131Xe nuclei. This leads to the most stringent upper limits on WIMP-neutron cross sections for WIMP masses above 6 GeV/c², with a minimum cross section of 3.5×10(-40) cm² at a WIMP mass of 45 GeV/c², at 90% confidence level.

13.
J Microbiol Methods ; 93(2): 102-7, 2013 May.
Article in English | MEDLINE | ID: mdl-23499920

ABSTRACT

Fourier-transform infrared (FTIR) spectroscopy was evaluated as an alternative method for serotyping encapsulated Streptococcus pneumonia strains. Sixty-nine invasive strains from the Microbiology Laboratory of the Medicine Faculty of University of Lisbon were selected for the analysis. The encapsulated strains used in this work (9N, 9V, 14, 19A, 19F, 23A, 23B and 23F) were serotyped by the standard capsular reaction test using the chessboard method and specific sera. FTIR spectra were analysed with chemometric methods. Results showed that the best spectral region unveiling serotype difference is located at 1185-900 cm(-1). A partial least squares discriminant analysis model was calibrated using this spectral region against the chessboard method serotyping. FTIR spectroscopy proved to be able to correctly predict 100% of strains according to the serogroups (9, 14, 19, 23). A segregated analysis showed that it was also possible to differentiate serotypes belonging to the same serogroup although spectral differences are less pronounced as was initially expected.


Subject(s)
Serotyping/methods , Spectroscopy, Fourier Transform Infrared/methods , Streptococcus pneumoniae/chemistry , Streptococcus pneumoniae/classification , Humans
14.
Phys Rev Lett ; 109(18): 181301, 2012 Nov 02.
Article in English | MEDLINE | ID: mdl-23215267

ABSTRACT

We report on a search for particle dark matter with the XENON100 experiment, operated at the Laboratori Nazionali del Gran Sasso for 13 months during 2011 and 2012. XENON100 features an ultralow electromagnetic background of (5.3 ± 0.6) × 10(-3) events/(keV(ee) × kg × day) in the energy region of interest. A blind analysis of 224.6 live days × 34 kg exposure has yielded no evidence for dark matter interactions. The two candidate events observed in the predefined nuclear recoil energy range of 6.6-30.5 keV(nr) are consistent with the background expectation of (1.0 ± 0.2) events. A profile likelihood analysis using a 6.6-43.3 keV(nr) energy range sets the most stringent limit on the spin-independent elastic weakly interacting massive particle-nucleon scattering cross section for weakly interacting massive particle masses above 8 GeV/c(2), with a minimum of 2 × 10(-45) cm(2) at 55 GeV/c(2) and 90% confidence level.

15.
Anal Bioanal Chem ; 404(4): 1211-37, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22644146

ABSTRACT

Biotechnological processes are crucial to the development of any economy striving to ensure a relevant position in future markets. The cultivation of microorganisms in bioreactors is one of the most important unit operations of biotechnological processes, and real-time monitoring of bioreactors is essential for effective bioprocess control. In this review, published material on the potential application of different spectroscopic techniques for bioreactor monitoring is critically discussed, with particular emphasis on optical fiber technology, reported for in situ bioprocess monitoring. Application examples are presented by spectroscopy type, specifically focusing on ultraviolet-visible, near-infrared, mid-infrared, Raman, and fluorescence spectroscopy. The spectra acquisition devices available and the major advantages and disadvantages of each spectroscopy are discussed. The type of information contained in the spectra and the available chemometric methods for extracting that information are also addressed, including wavelength selection, spectra pre-processing, principal component analysis, and partial least-squares. Sample handling techniques (flow and sequential injection analysis) that include transport to spectroscopic sensors for ex-situ on-line monitoring are not covered in this review.


Subject(s)
Bacteria/metabolism , Bioreactors/microbiology , Biotechnology/methods , Spectrum Analysis/methods
16.
J. venom. anim. toxins incl. trop. dis ; 18(1): 73-82, 2012. ilus
Article in English | LILACS | ID: lil-618192

ABSTRACT

Bothropic envenomation induces hemorrhage, coagulant disturbances and necrosis. Regarding therapies against the local damage caused by the venom, there is little information on tissue changes until the complete healing. In the current study, local damage was evaluated by examination of morphological inflammatory alterations, mast cell count, and analysis of collagen deposition. Bleeding was evident four hours after inoculation. After 24 hours, a large area of injury appeared presenting disorganized tissue, significant hemorrhage and acute inflammation. After three days, the damaged area was extensive, with a large amount of inflammatory cells and the presence of scab. In seven days, healing and reepithelization process started. And, 21 days later, the epithelium showed less infiltration and no skin appendages. The number of mast cells was similar to control after four hours, with a drop of 50 percent at 24 hours, followed by an increase until the 21st day. No differences of collagen deposition were observed among experimental groups. Taken together, wound healing after intradermal injection of Bothrops cotiara venom in mice follows similar parameters to wounds caused by other bothropic venoms. The present work reveals the importance of experimental wound models to the study of neutralizing agents against venom toxins.


Subject(s)
Animals , Mice , Bothrops , Poisons , Wound Healing
17.
Phys Rev Lett ; 107(13): 131302, 2011 Sep 23.
Article in English | MEDLINE | ID: mdl-22026838

ABSTRACT

We present results from the direct search for dark matter with the XENON100 detector, installed underground at the Laboratori Nazionali del Gran Sasso of INFN, Italy. XENON100 is a two-phase time-projection chamber with a 62 kg liquid xenon target. Interaction vertex reconstruction in three dimensions with millimeter precision allows the selection of only the innermost 48 kg as the ultralow background fiducial target. In 100.9 live days of data, acquired between January and June 2010, no evidence for dark matter is found. Three candidate events were observed in the signal region with an expected background of (1.8 ± 0.6) events. This leads to the most stringent limit on dark matter interactions today, excluding spin-independent elastic weakly interacting massive particle (WIMP) nucleon scattering cross sections above 7.0 × 10(-45) cm(2) for a WIMP mass of 50 GeV/c(2) at 90% confidence level.

18.
Philos Trans A Math Phys Eng Sci ; 369(1953): 4064-77, 2011 Oct 28.
Article in English | MEDLINE | ID: mdl-21930565

ABSTRACT

It is now recognized that the International System of Units (SI units) will be redefined in terms of fundamental constants, even if the date when this will occur is still under debate. Actually, the best estimate of fundamental constant values is given by a least-squares adjustment, carried out under the auspices of the Committee on Data for Science and Technology (CODATA) Task Group on Fundamental Constants. This adjustment provides a significant measure of the correctness and overall consistency of the basic theories and experimental methods of physics using the values of the constants obtained from widely differing experiments. The physical theories that underlie this adjustment are assumed to be valid, such as quantum electrodynamics (QED). Testing QED, one of the most precise theories is the aim of many accurate experiments. The calculations and the corresponding experiments can be carried out either on a boundless system, such as the electron magnetic moment anomaly, or on a bound system, such as atomic hydrogen. The value of fundamental constants can be deduced from the comparison of theory and experiment. For example, using QED calculations, the value of the fine structure constant given by the CODATA is mainly inferred from the measurement of the electron magnetic moment anomaly carried out by Gabrielse's group. (Hanneke et al. 2008 Phys. Rev. Lett. 100, 120801) The value of the Rydberg constant is known from two-photon spectroscopy of hydrogen combined with accurate theoretical quantities. The Rydberg constant, determined by the comparison of theory and experiment using atomic hydrogen, is known with a relative uncertainty of 6.6×10(-12). It is one of the most accurate fundamental constants to date. A careful analysis shows that knowledge of the electrical size of the proton is nowadays a limitation in this comparison. The aim of muonic hydrogen spectroscopy was to obtain an accurate value of the proton charge radius. However, the value deduced from this experiment contradicts other less accurate determinations. This problem is known as the proton radius puzzle. This new determination of the proton radius may affect the value of the Rydberg constant . This constant is related to many fundamental constants; in particular, links the two possible ways proposed for the redefinition of the kilogram, the Avogadro constant N(A) and the Planck constant h. However, the current relative uncertainty on the experimental determinations of N(A) or h is three orders of magnitude larger than the 'possible' shift of the Rydberg constant, which may be shown by the new value of the size of the proton radius determined from muonic hydrogen. The proton radius puzzle will not interfere in the redefinition of the kilogram. After a short introduction to the properties of the proton, we will describe the muonic hydrogen experiment. There is intense theoretical activity as a result of our observation. A brief summary of possible theoretical explanations at the date of writing of the paper will be given. The contribution of the proton radius puzzle to the redefinition of SI-based units will then be examined.

19.
Phys Rev Lett ; 107(5): 051301, 2011 Jul 29.
Article in English | MEDLINE | ID: mdl-21867059

ABSTRACT

We report results of a search for light (≲10 GeV) particle dark matter with the XENON10 detector. The event trigger was sensitive to a single electron, with the analysis threshold of 5 electrons corresponding to 1.4 keV nuclear recoil energy. Considering spin-independent dark matter-nucleon scattering, we exclude cross sections σ(n)>7×10(-42) cm(2), for a dark matter particle mass m(χ)=7 GeV. We find that our data strongly constrain recent elastic dark matter interpretations of excess low-energy events observed by CoGeNT and CRESST-II, as well as the DAMA annual modulation signal.


Subject(s)
Cosmic Radiation , Data Interpretation, Statistical , Electrons , Nuclear Physics , Humans , Light , Photons , Scattering, Radiation
20.
Bone Marrow Transplant ; 46(11): 1399-408, 2011 Nov.
Article in English | MEDLINE | ID: mdl-21383682

ABSTRACT

Acute kidney injury (AKI) is a common complication in haematopoietic cell transplantation (HCT) patients and it adversely affects outcome. Herein, we provide a comprehensive and contemporary discussion of the incidence, risk factors and outcome of AKI in patients undergoing HCT, focusing on the differences between the myeloablative and nonmyeloablative regimens.


Subject(s)
Acute Kidney Injury/etiology , Hematopoietic Stem Cell Transplantation/adverse effects , Transplantation Conditioning/adverse effects , Acute Kidney Injury/epidemiology , Acute Kidney Injury/mortality , Cyclosporine/adverse effects , Graft vs Host Disease/complications , Hepatic Veno-Occlusive Disease/complications , Humans , Incidence , Myeloablative Agonists/adverse effects , Risk Factors , Treatment Outcome
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