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1.
Rev Med Chil ; 151(7): 947-952, 2023 Jul.
Article in English | MEDLINE | ID: mdl-39093185

ABSTRACT

Medullary thyroid cancer (MTC) is a rare disease from parafollicular C cells. Calcitonin has been suggested as a screening; its levels are proportional to the tumor size and predictive of metastatic disease. We present a case where an early action was taken with lower cut-off points. Male patient, 49 years old. Thyroid ultrasound (US) with a suspicious nodule. Fine Needle Aspiration Biopsy (FNAB) suggests MTC, with pre-operative serum calcitonin (CTN) of 591 pg/mL. Total thyroidectomy with central and bilateral dissection was performed. Biopsy: MTC in left nodule of 26 mm without lymph nodes (LN) metastases. Follow-up with undetectable CTN for six years. After that, CT was 4.7 pg/mL, and carcinoembryonic antigen (CEA) was 1.2 ng/mL. Neck US showed bilateral LN. FNAB of LN does not show recurrence. A progressive rise of markers with doubling time of CTN and CEA was 16 and 51.3 months, respectively. CTN raised until 112 pg/mL. Given the lack of cervical compromise, a neck and lung CT, liver MRI, and bone scintigraphy were ordered despite CTN levels < 150 pg/mL. MRI showed hypervascular hepatic lesions, contrasted with gadoxetic acid. PET Ga68-DOTATATE showed lesions with overexpression of somatostatin receptors in the liver. Surgery was done, and a biopsy confirmed metastases. Conclusions: The clinical guidelines may allow the management of cases; however, they should be used considering each case context. In our patient, if the guidelines had been strictly followed, it would not have been possible to detect liver metastases to achieve a surgical resection with curative intent.


Subject(s)
Carcinoma, Neuroendocrine , Thyroid Neoplasms , Humans , Thyroid Neoplasms/pathology , Thyroid Neoplasms/surgery , Male , Middle Aged , Carcinoma, Neuroendocrine/pathology , Carcinoma, Neuroendocrine/surgery , Carcinoma, Neuroendocrine/diagnostic imaging , Thyroidectomy , Calcitonin/blood , Biopsy, Fine-Needle , Carcinoembryonic Antigen/blood , Practice Guidelines as Topic , Biomarkers, Tumor/blood
2.
Mikrochim Acta ; 188(9): 302, 2021 Aug 20.
Article in English | MEDLINE | ID: mdl-34417662

ABSTRACT

An electroanalytical platform capable to take and dilute the sample has been designed in order to fully integrate the different steps of the analytical process in only one device. The concept is based on the addition of glass-fiber pads for sampling and diluting to an electrochemical cell combining a paper-based working electrode with low-cost connector headers as counter and reference electrodes. In order to demonstrate the feasibility of this all-in-one platform for biosensing applications, an enzymatic sensor for glucose determination (requiring a potential as low as -0.1 V vs. gold-plated wire by using ferrocyanide as mediator) was developed. Real food samples, such as cola beverages and orange juice, have been analyzed with the bioelectroanalytical lab-on-paper platform. As a proof-of-concept, and trying to go further in the integration of steps, sucrose was successfully detected by depositing invertase in the sampling strip. This enzyme hydrolyzes sucrose into fructose and glucose, which was determined using the enzymatic biosensor. This approach opens the pathway for the development of devices applying the lab-on-paper concept, saving costs and time, and making possible to perform decentralized analysis with high accuracy.


Subject(s)
Biosensing Techniques/methods , Electrochemical Techniques/methods , Glucose/analysis , Paper , Armoracia/enzymology , Biosensing Techniques/instrumentation , Carbonated Beverages/analysis , Citrus sinensis/chemistry , Electrochemical Techniques/instrumentation , Ferrocyanides/chemistry , Fruit and Vegetable Juices/analysis , Glucose/chemistry , Glucose Oxidase/chemistry , Horseradish Peroxidase/chemistry , Proof of Concept Study , Sucrose/analysis , Sucrose/chemistry , beta-Fructofuranosidase/chemistry
3.
Am J Transplant ; 17(10): 2640-2649, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28371433

ABSTRACT

Cardiovascular risk remains high in kidney transplant recipients (KTRs) despite improved kidney function after transplant. Urinary markers of kidney fibrosis and injury may help to reveal mechanisms of this risk. In a case-cohort study among stable KTRs who participated in the FAVORIT trial, we measured four urinary proteins known to correlate with kidney tubulointerstitial fibrosis on biopsy (urine alpha 1 microglobulin [α1m], monocyte chemoattractant protein-1 [MCP-1], procollagen type I [PINP] and type III [PIIINP] N-terminal amino peptide) and evaluated associations with cardiovascular disease (CVD) events (n = 300) and death (n = 371). In adjusted models, higher urine α1m (hazard ratio [HR] per doubling of biomarker 1.40 [95% confidence interval [CI] 1.21, 1.62]), MCP-1 (HR 1.18 [1.03, 1.36]), and PINP (HR 1.13 [95% CI 1.03, 1.23]) were associated with CVD events. These three markers were also associated with death (HR per doubling α1m 1.51 [95% CI 1.32, 1.72]; MCP-1 1.31 [95% CI 1.13, 1.51]; PINP 1.11 [95% CI 1.03, 1.20]). Higher concentrations of urine α1m, MCP-1, and PINP may identify KTRs at higher risk for CVD events and death. These markers may identify a systemic process of fibrosis involving both the kidney and cardiovascular system, and give new insights into mechanisms linking the kidney with CVD.


Subject(s)
Biomarkers/urine , Cardiovascular Diseases/urine , Kidney Transplantation , Nephritis, Interstitial/urine , Aged , Cardiovascular Diseases/epidemiology , Cardiovascular Diseases/prevention & control , Case-Control Studies , Female , Fibrosis , Folic Acid/administration & dosage , Humans , Kidney Transplantation/mortality , Male , Middle Aged , Risk Factors
4.
Phys Rev Lett ; 118(2): 022003, 2017 Jan 13.
Article in English | MEDLINE | ID: mdl-28128595

ABSTRACT

The first full amplitude analysis of B^{+}→J/ψϕK^{+} with J/ψ→µ^{+}µ^{-}, ϕ→K^{+}K^{-} decays is performed with a data sample of 3 fb^{-1} of pp collision data collected at sqrt[s]=7 and 8 TeV with the LHCb detector. The data cannot be described by a model that contains only excited kaon states decaying into ϕK^{+}, and four J/ψϕ structures are observed, each with significance over 5 standard deviations. The quantum numbers of these structures are determined with significance of at least 4 standard deviations. The lightest has mass consistent with, but width much larger than, previous measurements of the claimed X(4140) state.

5.
Phys Rev Lett ; 117(6): 061803, 2016 Aug 05.
Article in English | MEDLINE | ID: mdl-27541460

ABSTRACT

The CP asymmetry in the mixing of B_{s}^{0} and B[over ¯]_{s}^{0} mesons is measured in proton-proton collision data corresponding to an integrated luminosity of 3.0 fb^{-1}, recorded by the LHCb experiment at center-of-mass energies of 7 and 8 TeV. Semileptonic B_{s}^{0} and B[over ¯]_{s}^{0} decays are studied in the inclusive mode D_{s}^{∓}µ^{±}ν[over (-)]_{µ}X with the D_{s}^{∓} mesons reconstructed in the K^{+}K^{-}π^{∓} final state. Correcting the observed charge asymmetry for detection and background effects, the CP asymmetry is found to be a_{sl}^{s}=(0.39±0.26±0.20)%, where the first uncertainty is statistical and the second systematic. This is the most precise measurement of a_{sl}^{s} to date. It is consistent with the prediction from the standard model and will constrain new models of particle physics.

6.
Phys Rev Lett ; 117(8): 082003, 2016 Aug 19.
Article in English | MEDLINE | ID: mdl-27588849

ABSTRACT

A full amplitude analysis of Λ_{b}^{0}→J/ψpπ^{-} decays is performed with a data sample acquired with the LHCb detector from 7 and 8 TeV pp collisions, corresponding to an integrated luminosity of 3 fb^{-1}. A significantly better description of the data is achieved when, in addition to the previously observed nucleon excitations N→pπ^{-}, either the P_{c}(4380)^{+} and P_{c}(4450)^{+}→J/ψp states, previously observed in Λ_{b}^{0}→J/ψpK^{-} decays, or the Z_{c}(4200)^{-}→J/ψπ^{-} state, previously reported in B^{0}→J/ψK^{+}π^{-} decays, or all three, are included in the amplitude models. The data support a model containing all three exotic states, with a significance of more than three standard deviations. Within uncertainties, the data are consistent with the P_{c}(4380)^{+} and P_{c}(4450)^{+} production rates expected from their previous observation taking account of Cabibbo suppression.

7.
Phys Rev Lett ; 117(8): 082002, 2016 Aug 19.
Article in English | MEDLINE | ID: mdl-27588848

ABSTRACT

The data sample of Λ_{b}^{0}→J/ψpK^{-} decays acquired with the LHCb detector from 7 and 8 TeV pp collisions, corresponding to an integrated luminosity of 3 fb^{-1}, is inspected for the presence of J/ψp or J/ψK^{-} contributions with minimal assumptions about K^{-}p contributions. It is demonstrated at more than nine standard deviations that Λ_{b}^{0}→J/ψpK^{-} decays cannot be described with K^{-}p contributions alone, and that J/ψp contributions play a dominant role in this incompatibility. These model-independent results support the previously obtained model-dependent evidence for P_{c}^{+}→J/ψp charmonium-pentaquark states in the same data sample.

8.
Phys Rev Lett ; 116(24): 241801, 2016 Jun 17.
Article in English | MEDLINE | ID: mdl-27367383

ABSTRACT

Charm meson oscillations are observed in a time-dependent analysis of the ratio of D^{0}→K^{+}π^{-}π^{+}π^{-} to D^{0}→K^{-}π^{+}π^{-}π^{+} decay rates, using data corresponding to an integrated luminosity of 3.0 fb^{-1} recorded by the LHCb experiment. The measurements presented are sensitive to the phase-space averaged ratio of doubly Cabibbo-suppressed to Cabibbo-favored amplitudes r_{D}^{K3π} and the product of the coherence factor R_{D}^{K3π} and a charm mixing parameter y_{K3π}^{'}. The constraints measured are r_{D}^{K3π}=(5.67±0.12)×10^{-2}, which is the most precise determination to date, and R_{D}^{K3π}y_{K3π}^{'}=(0.3±1.8)×10^{-3}, which provides useful input for determinations of the CP-violating phase γ in B^{±}→DK^{±}, D→K^{∓}π^{±}π^{∓}π^{±} decays. The analysis also gives the most precise measurement of the D^{0}→K^{+}π^{-}π^{+}π^{-} branching fraction, and the first observation of D^{0}-D[over ¯]^{0} oscillations in this decay mode, with a significance of 8.2 standard deviations.

9.
Phys Rev Lett ; 116(24): 241601, 2016 Jun 17.
Article in English | MEDLINE | ID: mdl-27367382

ABSTRACT

Violations of CPT symmetry and Lorentz invariance are searched for by studying interference effects in B^{0} mixing and in B_{s}^{0} mixing. Samples of B^{0}→J/ψK_{S}^{0} and B_{s}^{0}→J/ψK^{+}K^{-} decays are recorded by the LHCb detector in proton-proton collisions at center-of-mass energies of 7 and 8 TeV, corresponding to an integrated luminosity of 3 fb^{-1}. No periodic variations of the particle-antiparticle mass differences are found, consistent with Lorentz invariance and CPT symmetry. Results are expressed in terms of the standard model extension parameter Δa_{µ} with precisions of O(10^{-15}) and O(10^{-14}) GeV for the B^{0} and B_{s}^{0} systems, respectively. With no assumption on Lorentz (non)invariance, the CPT-violating parameter z in the B_{s}^{0} system is measured for the first time and found to be Re(z)=-0.022±0.033±0.005 and Im(z)=0.004±0.011±0.002, where the first uncertainties are statistical and the second systematic.

10.
Phys Rev Lett ; 117(15): 152003, 2016 Oct 07.
Article in English | MEDLINE | ID: mdl-27768360

ABSTRACT

The B_{s}^{0}π^{±} invariant mass distribution is investigated in order to search for possible exotic meson states. The analysis is based on a data sample recorded with the LHCb detector corresponding to 3 fb^{-1} of pp collision data at sqrt[s]=7 and 8 TeV. No significant excess is found, and upper limits are set on the production rate of the claimed X(5568) state within the LHCb acceptance. Upper limits are also set as a function of the mass and width of a possible exotic meson decaying to the B_{s}^{0}π^{±} final state. The same limits also apply to a possible exotic meson decaying through the chain B_{s}^{*0}π^{±}, B_{s}^{*0}→B_{s}^{0}γ where the photon is excluded from the reconstructed decays.

11.
Phys Rev Lett ; 116(16): 161802, 2016 Apr 22.
Article in English | MEDLINE | ID: mdl-27152791

ABSTRACT

The first observation of the B_{s}^{0}→D[over ¯]^{0}K_{S}^{0} decay mode and evidence for the B_{s}^{0}→D[over ¯]^{*0}K_{S}^{0} decay mode are reported. The data sample corresponds to an integrated luminosity of 3.0 fb^{-1} collected in pp collisions by LHCb at center-of-mass energies of 7 and 8 TeV. The branching fractions are measured to be B(B_{s}^{0}→D[over ¯]^{0}K[over ¯]^{0})=[4.3±0.5(stat)±0.3(syst)±0.3(frag)±0.6(norm)]×10^{-4},B(B_{s}^{0}→D[over ¯]^{*0}K[over ¯]^{0})=[2.8±1.0(stat)±0.3(syst)±0.2(frag)±0.4(norm)]×10^{-4},where the uncertainties are due to contributions coming from statistical precision, systematic effects, and the precision of two external inputs, the ratio f_{s}/f_{d} and the branching fraction of B^{0}→D[over ¯]^{0}K_{S}^{0}, which is used as a calibration channel.

12.
Phys Rev Lett ; 116(19): 191601, 2016 May 13.
Article in English | MEDLINE | ID: mdl-27232015

ABSTRACT

A search for CP violation in D^{0}→K^{-}K^{+} and D^{0}→π^{-}π^{+} decays is performed using pp collision data, corresponding to an integrated luminosity of 3 fb^{-1}, collected using the LHCb detector at center-of-mass energies of 7 and 8 TeV. The flavor of the charm meson is inferred from the charge of the pion in D^{*+}→D^{0}π^{+} and D^{*-}→D[over ¯]^{0}π^{-} decays. The difference between the CP asymmetries in D^{0}→K^{-}K^{+} and D^{0}→π^{-}π^{+} decays, ΔA_{CP}≡A_{CP}(K^{-}K^{+})-A_{CP}(π^{-}π^{+}), is measured to be [-0.10±0.08(stat)±0.03(syst)]%. This is the most precise measurement of a time-integrated CP asymmetry in the charm sector from a single experiment.

13.
Langmuir ; 32(45): 11799-11812, 2016 11 15.
Article in English | MEDLINE | ID: mdl-27797530

ABSTRACT

Dilute isotropic collagen solutions are usually flow processed into monodomain chiral nematic thin films for obtaining highly ordered materials by a multistep process that starts with complex inhomogeneous flow kinematics. Here we present rigorous theory and simulation of the initial precursors during flow steps in cholesteric collagen film formation. We first extract the molecular shape parameter and rotational diffusivity from previously reported simple shear data of dilute collagen solutions, where the former leads the reactive parameter (tumbling function) which determines the net effect of vorticity and strain rate on the average orientation and where the latter establishes the intensity of strain required for flow-birefringence, both crucial quantities for controlled film formation flow. We find that the tumbling function is similar to those of rod-like lyotropic liquid crystalline polymers and hence it is predicted that they would tumble in the ordered high concentration state leading to flow-induced texturing. The previously reported experimental data is well fitted with rotational diffusivities whose order of magnitude is consistent to those of other biomacromolecules. We then investigate the response of the tensor order parameter to complex flow kinematics, ranging from pure vorticity, through simple shear, to extensional flow, as may arise in typical flow casting and film flows. The chosen control variable to produce precursor cholesteric films is the director or average orientation, since the nematic order is set close to typical values found in concentrated cholesteric type I collagen solutions. Using the efficient four-roll mill kinematics, we summarize the para-nematic structure-flow process diagram in terms of the director orientation and flow type. Using analysis and computation, we provide a parametric envelope that is necessary to eventually produce well-aligned cholesteric films. We conclude that extensional flow is an essential ingredient of well-ordered film precursors with required Deborah numbers on the order of unity.


Subject(s)
Collagen/chemistry , Models, Theoretical , Birefringence , Computer Simulation , Reproducibility of Results , Solutions/chemistry
15.
Rev Med Chil ; 144(9): 1226-1229, 2016 Sep.
Article in Spanish | MEDLINE | ID: mdl-28060988

ABSTRACT

Neuromyelitis optica (NMO) is a severe demyelinating disease of the central nervous system, which preferentially attacks the optic nerve and spinal cord. It is associated with antibodies against aquaporin 4. Morbidity and mortality are higher than in multiple sclerosis and its treatment focuses on immunosuppressive drugs. Immunomodulators are contraindicated. We report a previously healthy 35-year-old man, presenting with NMO concomitantly with systemic lupus erythematosus. His evolution was torpid with three outbreaks in the 10 months after the diagnosis, requiring a first-line therapy with methylprednisolone and cyclophosphamide and then a second-line therapy with rituximab.


Subject(s)
Lupus Erythematosus, Systemic/complications , Neuromyelitis Optica/complications , Adult , Antirheumatic Agents/therapeutic use , Cyclophosphamide/therapeutic use , Glucocorticoids/therapeutic use , Humans , Lupus Erythematosus, Systemic/drug therapy , Male , Methylprednisolone/therapeutic use , Neuromyelitis Optica/drug therapy , Paresis/complications , Paresis/drug therapy , Rituximab/therapeutic use , Spasm/complications , Spasm/drug therapy
16.
Appl Environ Microbiol ; 81(20): 7271-80, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26253681

ABSTRACT

The coexistence of sulfate-reducing bacteria (SRB) and methanogenic archaea (MA) in anaerobic biofilms developed in sewer inner pipe surfaces favors the accumulation of sulfide (H2S) and methane (CH4) as metabolic end products, causing severe impacts on sewerage systems. In this study, we investigated the time course of H2S and CH4 production and emission rates during different stages of biofilm development in relation to changes in the composition of microbial biofilm communities. The study was carried out in a laboratory sewer pilot plant that mimics a full-scale anaerobic rising sewer using a combination of process data and molecular techniques (e.g., quantitative PCR [qPCR], denaturing gradient gel electrophoresis [DGGE], and 16S rRNA gene pyrotag sequencing). After 2 weeks of biofilm growth, H2S emission was notably high (290.7±72.3 mg S-H2S liter(-1) day(-1)), whereas emissions of CH4 remained low (17.9±15.9 mg COD-CH4 liter(-1) day(-1)). This contrasting trend coincided with a stable SRB community and an archaeal community composed solely of methanogens derived from the human gut (i.e., Methanobrevibacter and Methanosphaera). In turn, CH4 emissions increased after 1 year of biofilm growth (327.6±16.6 mg COD-CH4 liter(-1) day(-1)), coinciding with the replacement of methanogenic colonizers by species more adapted to sewer conditions (i.e., Methanosaeta spp.). Our study provides data that confirm the capacity of our laboratory experimental system to mimic the functioning of full-scale sewers both microbiologically and operationally in terms of sulfide and methane production, gaining insight into the complex dynamics of key microbial groups during biofilm development.


Subject(s)
Archaea/metabolism , Bacteria/metabolism , Biofilms/growth & development , Sewage/microbiology , Anaerobiosis , Methane/metabolism , Molecular Sequence Data , RNA, Ribosomal, 16S/genetics , Sulfates/metabolism , Sulfides/metabolism
17.
Phys Rev Lett ; 114(6): 062004, 2015 Feb 13.
Article in English | MEDLINE | ID: mdl-25723210

ABSTRACT

Two structures are observed close to the kinematic threshold in the Ξ(b)(0)π(-) mass spectrum in a sample of proton-proton collision data, corresponding to an integrated luminosity of 3.0 fb(-1), recorded by the LHCb experiment. In the quark model, two baryonic resonances with quark content bds are expected in this mass region: the spin-parity J(P)=(1/2)(+) and J(P)=(3/2)(+) states, denoted Ξ(b)('-) and Ξ(b)(*-). Interpreting the structures as these resonances, we measure the mass differences and the width of the heavier state to be m(Ξ(b)('-))-m(Ξ(b)(0))-m(π(-))=3.653±0.018±0.006 MeV/c(2), m(Ξ(b)(*-))-m(Ξ(b)(0))-m(π(-))=23.96±0.12±0.06 MeV/c(2), Γ(Ξ(b)(*-))=1.65±0.31±0.10 MeV, where the first and second uncertainties are statistical and systematic, respectively. The width of the lighter state is consistent with zero, and we place an upper limit of Γ(Ξ(b)('-))<0.08 MeV at 95% confidence level. Relative production rates of these states are also reported.

18.
Phys Rev Lett ; 114(13): 132001, 2015 Apr 03.
Article in English | MEDLINE | ID: mdl-25884121

ABSTRACT

Production of Bc+ mesons in proton-proton collisions at a center-of-mass energy of 8 TeV is studied with data corresponding to an integrated luminosity of 2.0 fb-1 recorded by the LHCb experiment. The ratio of production cross sections times branching fractions between the Bc+→J/ψπ+ and B+→J/ψK+ decays is measured as a function of transverse momentum and rapidity in the regions 0

19.
Phys Rev Lett ; 114(4): 041601, 2015 Jan 30.
Article in English | MEDLINE | ID: mdl-25679884

ABSTRACT

The semileptonic CP asymmetry in B0-B[over ¯]0 mixing, a(sl)(d), is measured in proton-proton collision data, corresponding to an integrated luminosity of 3.0 fb-1, recorded by the LHCb experiment. Semileptonic B0 decays are reconstructed in the inclusive final states D-µ+ and D*-µ+, where the D- meson decays into the K+π-π- final state and the D*- meson into the D[over ¯]0(→K+π-)π- final state. The asymmetry between the numbers of D(*)-µ+ and D(*)+µ- decays is measured as a function of the decay time of the B0 mesons. The CP asymmetry is measured to be a(sl)(d)=(-0.02±0.19±0.30)%, where the first uncertainty is statistical and the second systematic. This is the most precise measurement of a(sl)(d) to date and is consistent with the prediction from the standard model.

20.
Phys Rev Lett ; 114(4): 041801, 2015 Jan 30.
Article in English | MEDLINE | ID: mdl-25679885

ABSTRACT

The time-dependent CP asymmetry in B(s)(0)→J/ψK+K- decays is measured using pp collision data, corresponding to an integrated luminosity of 3.0 fb-1, collected with the LHCb detector at center-of-mass energies of 7 and 8 TeV. In a sample of 96,000 B(s)(0)→J/ψK+K- decays, the CP-violating phase ϕs is measured, as well as the decay widths ΓL and ΓH of the light and heavy mass eigenstates of the B(s)(0)-B[over ¯]s0 system. The values obtained are ϕs=-0.058±0.049±0.006 rad, Γs≡(ΓL+ΓH)/2=0.6603±0.0027±0.0015 ps-1, and ΔΓs≡ΓL-ΓH=0.0805±0.0091±0.0032 ps-1, where the first uncertainty is statistical and the second, systematic. These are the most precise single measurements of those quantities to date. A combined analysis with Bs0→J/ψπ+π- decays gives ϕs=-0.010±0.039 rad. All measurements are in agreement with the standard model predictions. For the first time, the phase ϕs is measured independently for each polarization state of the K+K- system and shows no evidence for polarization dependence.

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