222 research outputs found
Determinants of enhanced thromboxane biosynthesis in renal transplantation
Background. Despite great improvement in patient and graft survival, the long-term morbidity and mortality in renal transplant recipients (RTRs) are still significant, with a high incidence of cardiovascular disease-related deaths. Methods. We investigated thromboxane (TXA2) biosynthesis and endothelial and coagulative activation in 65 patients who received a renal transplant. Results. The rate of TXA2 biosynthesis (urinary 11-dehydro-TXB2 excretion largely reflects platelet TXA2 production in vivo) was significantly (P < 0.0001) higher in RTRs than in healthy subjects. Plasma von Willebrand factor (vWF) and thrombin-antithrombin (TAT) complexes were significantly higher (P < 0.001) in RTRs compared with controls. Urinary 11-dehydro-TXB2 directly correlated with plasma vWF and cholesterol. We next examined the relative influence of cyclosporine A (CsA) on TXA2 biosynthesis and endothelial activation, comparing a group of RTRs not receiving CsA with an age- and sex-matched group of patients treated with CsA. Urinary excretion of 11-dehydro-TXB2 and plasma levels of vWF were significantly increased in RTRs who received CsA compared with those who did not. After an overall follow-up of 120 months, RTRs who experienced cardiovascular events had a higher frequency of abnormal plasma levels of vWF than patients who remained event free. Conclusion. Renal transplantation is associated with in vivo platelet activation highly related to endothelial activation. This is particularly evident in CsA-treated patients. Administration of drugs that are able to reduce or eliminate thromboxane-dependent platelet activation in vivo may be beneficial to reduce the risk of cardiovascular events in RTRs
In pursuit of giants: I. The evolution of the dust-to-stellar mass ratio in distant dusty galaxies
The dust-to-stellar mass ratio (Mdust/M?) is a crucial, albeit poorly constrained, parameter for improving our understanding of the
complex physical processes involved in the production of dust, metals, and stars in galaxy evolution. In this work, we explore trends
of Mdust/M? with dierent physical parameters and using observations of 300 massive dusty star-forming galaxies detected with
ALMA up to z 5. Additionally, we interpret our findings with dierent models of dusty galaxy formation. We find that Mdust/M?
evolves with redshift, stellar mass, specific star formation rates, and integrated dust size, but that evolution is dierent for mainsequence
galaxies than it is for starburst galaxies. In both galaxy populations, Mdust/M? increases until z 2, followed by a roughly
flat trend towards higher redshifts, suggesting ecient dust growth in the distant universe. We confirm that the inverse relation
between Mdust/M? and M? holds up to z 5 and can be interpreted as an evolutionary transition from early to late starburst phases.
We demonstrate that the Mdust/M? in starbursts reflects the increase in molecular gas fraction with redshift and attains the highest
values for sources with the most compact dusty star formation. State-of-the-art cosmological simulations that include self-consistent
dust growth have the capacity to broadly reproduce the evolution of Mdust/M? in main-sequence galaxies, but underestimating it in
starbursts. The latter is found to be linked to lower gas-phase metallicities and longer dust-growth timescales relative to observations.
The results of phenomenological models based on the main-sequence and starburst dichotomy as well as analytical models that include
recipes for rapid metal enrichment are consistent with our observations. Therefore, our results strongly suggest that high Mdust/M?
is due to rapid dust grain growth in the metal-enriched interstellar medium. This work highlights the multi-fold benefits of using
Mdust/M? as a diagnostic tool for: (1) disentangling main-sequence and starburst galaxies up to z 5; (2) probing the evolutionary
phase of massive objects; and (3) refining the treatment of the dust life cycle in simulations
Theory of anyon excitons: Relation to excitons of nu=1/3 and nu=2/3 incompressible liquids
Elementary excitations of incompressible quantum liquids (IQL's) are anyons,
i.e., quasiparticles carrying fractional charges and obeying fractional
statistics. To find out how the properties of these quasiparticles manifest
themselves in the optical spectra, we have developed the anyon exciton model
(AEM) and compared the results with the finite-size data for excitons of nu=1/3
and nu=2/3 IQL's. The model considers an exciton as a neutral composite
consisting of three quasielectrons and a single hole. The AEM works well when
the separation between electron and hole confinement planes, h, is larger than
the magnetic length l. In the framework of the AEM an exciton possesses
momentum k and two internal quantum numbers, one of which can be chosen as the
angular momentum, L, of the k=0 state. Existence of the internal degrees of
freedom results in the multiple branch energy spectrum, crater-like electron
density shape and 120 degrees density correlations for k=0 excitons, and the
splitting of the electron shell into bunches for non-zero k excitons. For h
larger than 2l the bottom states obey the superselection rule L=3m (m are
integers starting from 2), all of them are hard core states. For h nearly 2l
there is one-to-one correspondence between the low-energy spectra found for the
AEM and the many- electron exciton spectra of the nu=2/3 IQL, whereas some
states are absent from the many-electron spectra of the nu=1/3 IQL. We argue
that this striking difference in the spectra originates from the different
populational statistics of the quasielectrons of charge conjugate IQL's and
show that the proper account of the statistical requirements eliminates
excessive states from the spectrum. Apparently, this phenomenon is the first
manifestation of the exclusion statistics in the anyon bound states.Comment: 26 pages with 9 figures, typos correcte
Correction to: Multiple endocrine neoplasia type 1: analysis of germline MEN1 mutations in the Italian multicenter MEN1 patient database.
The original version of this article unfortunately contained a mistake in Table 2. The table 2 was truncated in the original publication. The full table 2 is given below
Association of kidney disease measures with risk of renal function worsening in patients with type 1 diabetes
Background: Albuminuria has been classically considered a marker of kidney damage progression in diabetic patients and it is routinely assessed to monitor kidney function. However, the role of a mild GFR reduction on the development of stage 653 CKD has been less explored in type 1 diabetes mellitus (T1DM) patients. Aim of the present study was to evaluate the prognostic role of kidney disease measures, namely albuminuria and reduced GFR, on the development of stage 653 CKD in a large cohort of patients affected by T1DM. Methods: A total of 4284 patients affected by T1DM followed-up at 76 diabetes centers participating to the Italian Association of Clinical Diabetologists (Associazione Medici Diabetologi, AMD) initiative constitutes the study population. Urinary albumin excretion (ACR) and estimated GFR (eGFR) were retrieved and analyzed. The incidence of stage 653 CKD (eGFR < 60 mL/min/1.73 m2) or eGFR reduction > 30% from baseline was evaluated. Results: The mean estimated GFR was 98 \ub1 17 mL/min/1.73m2 and the proportion of patients with albuminuria was 15.3% (n = 654) at baseline. About 8% (n = 337) of patients developed one of the two renal endpoints during the 4-year follow-up period. Age, albuminuria (micro or macro) and baseline eGFR < 90 ml/min/m2 were independent risk factors for stage 653 CKD and renal function worsening. When compared to patients with eGFR > 90 ml/min/1.73m2 and normoalbuminuria, those with albuminuria at baseline had a 1.69 greater risk of reaching stage 3 CKD, while patients with mild eGFR reduction (i.e. eGFR between 90 and 60 mL/min/1.73 m2) show a 3.81 greater risk that rose to 8.24 for those patients with albuminuria and mild eGFR reduction at baseline. Conclusions: Albuminuria and eGFR reduction represent independent risk factors for incident stage 653 CKD in T1DM patients. The simultaneous occurrence of reduced eGFR and albuminuria have a synergistic effect on renal function worsening
Uso del láser en urgencias por periodontitis apical post tratamiento endodóntico
Introduction: Laser therapy and stimulation of the acupuncture points are anti-inflammatory and analgesic alternative treatments in dentistry.Objective: to describe the use of low power laser therapy in the emergency treatment of apical periodontitis after endodontic treatment during 2018.Methods: observational, descriptive, longitudinal, and prospective study of patients who attended emergency department at Guama Dentistry Clinic during 2018, Pinar del RÃo, presenting apical periodontitis after endodontic treatment; 86 patients participated in the study. Descriptive statistics was applied, respecting the bioethical principles.Results: female gender predominated (53,49 %), apical periodontitis after endodontic treatment was more prevalent in the age group 20-24 (30,23 %); 65,5 % of the patients presented remission and relief after the third treatment session. Only 2,33 % needed more than six treatment sessions.Conclusions: apical periodontitis after endodontic treatment is more common in women during the first half of the second decade of life. The treatment showed effectiveness from the first treatment sessions.Introducción: la terapia y estimulación con láser en puntos acupunturales constituyen alternativas de tratamiento antiinflamatorio y analgésico en estomatologÃa.Objetivo: describir el uso de la terapia láser de baja potencia en el tratamiento de urgencias por periodontitis apical post tratamiento endodóntico durante el 2018.Método: estudio observacional, descriptivo, longitudinal y prospectivo en pacientes que acudieron a la consulta de urgencias de la ClÃnica Estomatológica “Guamá’’, municipio Pinar del RÃo, en el perÃodo durante el año 2018, por presentar periodontitis apical post tratamiento endodóntico. El universo estuvo constituido por 86 pacientes trabajándose con la totalidad. Se empleó estadÃstica descriptiva y se siguieron los principios bioéticos.Resultados: predominó el sexo femenino (53,49 %), donde la periodontitis apical post tratamiento endodóntico se presentó en mayor cuantÃa en el grupo etario de 20 a 24 años de edad (30,23 %). El 65,5 % de los pacientes presentaron remisión y alivio tras la tercera sesión de tratamiento. Solo el 2,33 % necesitó más de seis sesiones de tratamiento.Conclusiones: la periodontitis apical post tratamiento endodóntico se presentan en mayor cuantÃa en las féminas, durante la primera mitad de la segunda década de vida. El tratamiento con terapia laser de baja frecuencia mostró efectividad desde las primeras sesiones de tratamiento
Insights into deposition of Lower Cretaceous black shales from meager accumulation of organic matter in Albian sediments from ODP site 763, Exmouth Plateau, Northwest Australia
The amount and type of organic matter present in an exceptionally complete upper Aptian to lower Cenomanian sequence of sediments from ODP site 763 on the Exmouth Plateau has been determined. Organic carbon concentrations average 0.2%. Organic matter is marine in origin, and its production and preservation was low over the ca. 20-million-year interval recorded by this sequence. Because this section was tectonically isolated from mainland Australia in the early Aptian, it better represents global oceanic conditions than the many basin-edge locations in which Albian-age black shales have been found. Formation of the basin-edge black shales evidently resulted from rapid, turbiditic burial of organic matter rather than from enhanced oceanic production or from basin-wide anoxia during the Albian.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47134/1/367_2005_Article_BF02202605.pd
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