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1.
Lett Appl Microbiol ; 61(2): 113-20, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25976592

RESUMEN

UNLABELLED: Tomato spotted wilt virus (TSWV), Dahlia mosaic virus (DMV) and Chrysanthemum stunt viroid (CSVd) are economically important viruses and viroid that infect cultivated dahlias. Prior to this investigation, no multiplex RT-PCR assay for the detection of dahlia virus and viroid infections existed. In this study, we report the development of a multiplex RT-PCR that simultaneously detects TSWV, DMV and CSVd infections in dahlias. In addition, a simple RT-PCR method that does not require RNA extraction, microtissue direct RT-PCR, could be used to prepare samples for analysis by this multiplex RT-PCR. A field survey validated our results, indicating that TSWV was the dominant virus found in the Kansai region, DMV in the Tohoku and Kyushu regions, and CSVd in the Hokkaido region. This method represents a rapid, sensitive and cost effective approach to diagnose viral infections in dahlias. SIGNIFICANCE AND IMPACT OF THE STUDY: The multiplex RT-PCR assay described in this study is the first report of simultaneous detection of virus and viroid in dahlia. This method represents a rapid, sensitive and cost effective approach to diagnose viral infections in dahlias. A field survey validated our results, indicating that TSWV was the dominant virus found in the Kansai region, DMV in the Tohoku and Kyushu regions and CSVd in the Hokkaido region.


Asunto(s)
Dahlia/virología , Virus del Mosaico/aislamiento & purificación , Reacción en Cadena de la Polimerasa Multiplex/métodos , Enfermedades de las Plantas/virología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Tospovirus/aislamiento & purificación , Viroides/aislamiento & purificación , Chrysanthemum/virología , Datos de Secuencia Molecular , Virus del Mosaico/genética , Tospovirus/genética , Viroides/genética
3.
J Phys Condens Matter ; 36(12)2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-38056003

RESUMEN

We report the properties of an A-site spinel magnet, CoAl2-xGaxO4, and analyze its anomalous, low-temperature magnetic behavior, which is derived from inherent, magnetically frustrated interactions. Rietveld analysis of the x-ray diffraction profile for CoAl2-xGaxO4revealed that the metallic ions were randomly distributed in the tetrahedral (A-) and octahedral (B-) sites in the cubic spinel structure. The inversion parameterηcould be controlled by varying the gallium (Ga) composition in the range 0.055 ⩽η⩽ 0.664. The composition-induced Néel-to-spin-glass (NSG) transition occurred between 0.05 ⩽η⩽ 0.08 and was verified by measurements of DC-AC susceptibilitiesχand thermoremanent magnetization (TRM) below the Néel transition temperatureTN. The relaxation rate and derivative with respect to temperature of TRM increased at bothTNand the spin glass (SG) transition temperatureTSG. The TRM decayed rapidly above and below these transitions. TRM was highly sensitive to macroscopic magnetic transitions that occurred in both the Néel and SG phases of CoAl2-xGaxO4. In the vicinity of the NSG boundary, there was a maximum of the TRM relaxation rate atTmax

4.
J Phys Condens Matter ; 35(28)2023 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-37015243

RESUMEN

We report the first study of electrical resistivity, magnetization, and specific heat on YbCo2. The measurements on a single-phased sample of YbCo2bring no evidence of magnetic ordering down to 0.3 K in a zero magnetic field. The manifestations of low Kondo temperature are observed. The specific heat value divided by temperature,C/T, keeps increasing logarithmically beyond 7 J/mol K2with decreasing temperature down to 0.3 K without no sign of magnetic ordering, suggesting a very large electronic specific heat. Analysis of the magnetic specific heat indicates that the large portion of the low-temperature specific heat is not explained simply by the low Kondo temperature but is due to the strong intersite magnetic correlation in both the 3dand 4felectrons. Temperature-dependent measurements under static magnetic fields up to 7 T are carried out, which show the evolution of field-induced transition above 2 T. The transition temperature increases with increasing field, pointing to a ferromagnetic character. The extrapolation of the transition temperature to zero field suggests that YbCo2is in the very proximity of the quantum critical point. These results indicate that in the unique case of YbCo2, the itinerant electron magnetism of Co 3d-electrons and the Kondo effect within the vicinity of quantum criticality of Yb 4f-local moments can both play a role.

5.
Phys Rev Lett ; 108(5): 057001, 2012 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-22400952

RESUMEN

We report a high-pressure single crystal study of the topological superconductor Cu{x}Bi{2}Se{3}. Resistivity measurements under pressure show superconductivity is depressed smoothly. At the same time the metallic behavior is gradually lost. The upper-critical field data B{c2}(T) under pressure collapse onto a universal curve. The absence of Pauli limiting and the comparison of B{c2}(T) to a polar-state function point to spin-triplet superconductivity, but an anisotropic spin-singlet state cannot be discarded completely.

6.
J Exp Med ; 193(2): 263-9, 2001 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-11208867

RESUMEN

Signal transducer and activator of transcription (STAT)-induced STAT inhibitor 1 (SSI-1) is known to function as a negative feedback regulator of cytokine signaling, but it is unclear whether it is involved in other biological events. Here, we show that SSI-1 participates and plays an important role in the insulin signal transduction pathway. SSI-1-deficient mice showed a significantly low level of blood sugar. While the forced expression of SSI-1 reduced the phosphorylation level of insulin receptor substrate 1 (IRS-1), SSI-1 deficiency resulted in sustained phosphorylation of IRS-1 in response to insulin.Furthermore, SSI-1 achieves this inhibition both by binding directly to IRS-1 and by suppressing Janus kinases. These findings suggest that SSI-1 acts as a negative feedback factor also in the insulin signal transduction pathway through the suppression of IRS-1 phosphorylation.


Asunto(s)
Proteínas Portadoras/metabolismo , Insulina/metabolismo , Fosfoproteínas/metabolismo , Proteínas Represoras , Animales , Secuencia de Bases , Proteínas Portadoras/genética , Cartilla de ADN/genética , Retroalimentación , Hipoglucemia/genética , Hipoglucemia/metabolismo , Insulina/farmacología , Proteínas Sustrato del Receptor de Insulina , Proteínas Quinasas JNK Activadas por Mitógenos , Ratones , Ratones Noqueados , Proteínas Quinasas Activadas por Mitógenos/antagonistas & inhibidores , Fosforilación , ARN Mensajero/biosíntesis , ARN Mensajero/genética , Transducción de Señal , Proteína 1 Supresora de la Señalización de Citocinas , Proteínas Supresoras de la Señalización de Citocinas
7.
J Phys Condens Matter ; 32(42): 425601, 2020 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-32585641

RESUMEN

There is an ongoing dispute in the community about the absence of a magnetic quantum critical point (QCP) in the noncentrosymmetric heavy fermion compound CeRhSi3. In order to explore this question we prepared single crystals of CeRh(Si1-x Ge x )3 with x = 0.05 and 0.15 and determined the temperature-pressure (T-p) phase diagram by means of measurements of the electrical resistivity. The substitution of isoelectronic but large Ge enforces a lattice volume increase resulting in a weakening of the Kondo interaction. As a result, the x = 0.05 and x = 0.15 compound exhibit a transition into the antiferromagnetic (AFM) at higher temperatures being T N = 4.7 K and T N1 = 19.7 K, respectively. Application of pressure suppresses T N (T N1) monotonically and pressure induced superconductivity is observed in both Ge-substituted compounds above p ⩾ 2.16 GPa (x = 0.05) and p ⩾ 2.93 GPa (x = 0.15). Extrapolation of T N(p) → 0 of CeRh(Si0.95Ge0.05)3 yields a critical pressure of p c ≈ 3.4 GPa (in CeRh(Si0.85Ge0.15)3 p c ≈ 3.5 GPa) pointing to the presence of an AFM QCP located deep inside the superconducting state.

8.
J Phys Condens Matter ; 32(2): 025603, 2020 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-31574487

RESUMEN

The Dirac semimetal PdTe2 was recently reported to be a type-I superconductor (T c = 1.64 K, [Formula: see text] mT) with unusual superconductivity of the surface sheath. We here report a high-pressure study, [Formula: see text] GPa, of the superconducting phase diagram extracted from ac-susceptibility and transport measurements on single crystalline samples. T c (p ) shows a pronounced non-monotonous variation with a maximum T c = 1.91 K around 0.91 GPa, followed by a gradual decrease to 1.27 K at 2.5 GPa. Surface superconductivity is robust under pressure as demonstrated by the large superconducting screening signal that persists for applied dc-fields [Formula: see text]. Surprisingly, for [Formula: see text] GPa the superconducting transition temperature at the surface [Formula: see text] is larger than T c of the bulk. Therefore surface superconductivity may possibly have a non-trivial topological nature. We compare the measured pressure variation of T c with recent results from band structure calculations and discuss the importance of a Van Hove singularity.

9.
Trends Biochem Sci ; 24(10): 394-8, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10500304

RESUMEN

The growth and differentiation of cells that make up multicellular entities such as the blood and immune systems are under the control of glycoprotein mediators known as cytokines. These cytokines bind to membrane receptors on the cell surface and initiate a signaling cascade that ends with the transcription of specific sets of genes within the cell nucleus. Although knowledge is accumulating concerning the intracellular signal pathways that are activated by cytokines, little is known about inhibition of cytokine signals. This review will focus on the negative regulation of the Janus tyrosine kinase (JAK)/signal transducers and activators of transcription (STAT) signaling pathway by proteins related to STAT-induced STAT inhibitor-1 (SSI-1).


Asunto(s)
Proteínas Portadoras/metabolismo , Citocinas/metabolismo , Proteínas Represoras , Transducción de Señal , Factores de Transcripción/metabolismo , Animales , Ratones , Ratones Noqueados , Proteína 1 Supresora de la Señalización de Citocinas , Proteínas Supresoras de la Señalización de Citocinas
10.
Int J Artif Organs ; 31(10): 905-9, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19009509

RESUMEN

AIM: To assess the resistance posed by double-lumen vascular access dialysis catheters at low and high blood flow. DESIGN: Controlled ex vivo study Setting: ICU Laboratory of tertiary hospital. SUBJECTS: Eleven proprietary vascular access catheters for continuous renal replacement therapy. METHODS: Heparinized spent red cells diluted in polygeline solution were pumped using the Aquarius hemofiltration machine (Edwards Life Sciences, Sydney, NSW, Australia) and its standard circuit through several vascular access catheters. Blood flow was increased and then decreased in steps of 50 ml/min (50, 150, 200, 250 and 300 ml/min) while catheter outflow and inflow pressures were recorded. The pressure-flow relationship (hydraulic resistance) of each catheter was then calculated. Study catheters were divided into two groups according to their internal diameter (large gauge vs. smaller gauge) or length (long or short). Hydraulic resistances were compared between the groups. RESULTS: Different double lumen catheters posed clearly different resistances to flow. For all groups of catheters, there was a linear relationship between pressure and flow. No statistically significant difference between short and long catheters could be demonstrated (p=0.715). On the other hand, larger gauge catheters (13 Fr or greater) had significantly lower resistances than smaller gauge (<13 Fr) catheters (p=0.0062). Furthermore, all larger gauge catheters had resistances lower than 0.430 mmHg/ml/min, while all smaller gauge catheters had resistances greater than 0.490 mmHg/ml/min. CONCLUSIONS: Commercial double-lumen dialysis catheters have variable resistance to blood flow under standard ex vivo conditions. Although both length and internal diameter varied, internal diameter had a dominant effect on resistance. This information might be useful to clinicians in guiding their choice of catheters for clinical use.


Asunto(s)
Catéteres de Permanencia , Terapia de Reemplazo Renal/métodos , Velocidad del Flujo Sanguíneo/fisiología , Presión Sanguínea/fisiología , Catéteres de Permanencia/efectos adversos , Diseño de Equipo , Eritrocitos , Heparina , Humanos , Presión , Resistencia Vascular/fisiología
11.
Int J Artif Organs ; 31(3): 228-36, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18373316

RESUMEN

PURPOSE: To compare the acid-base balance effects of two different citrate doses for regional citrate anticoagulant (RCA) for continuous veno-venous hemofiltration (CVVH). METHODS: We used a commercial citrate fluid (citrate concentration: 11 mmol/L) from July 2003 to July 2004 (period A) in 22 patients; then changed to a new citrate fluid (citrate concentration: 14 mmol/L) from July 2004 to Feb 2005 (Period B) in 21 patients. Replacement fluid rate was fixed at 2,000 ml/h. We measured all relevant variables for acid-base analysis according to the Stewart-Figge methodology. RESULTS: After commencement of RCA-CVVH, there was a change in bicarbonate and base excess (BE) toward acidosis for both fluids. This change was significantly different between period A and B at 6 and 12 hours (pH: p<0.01, BE: p<0.05) with greater decreases with the 11 mmol/L citrate fluid. These changes were mostly secondary to an increase in the strong ion difference (SID) and occurred despite an increased strong ion gap (SIG) (+0.5 mEq/L vs. +1.5 mEq/L; p<0.01) in the higher citrate concentration fluid. Cessation of RCA-CVVH was associated with short-lived differences in bicarbonate and SIG which were similar to those seen on initiation of RCA-CVVH but in the opposite direction. CONCLUSIONS: A small increase This was partly offset by an increase in SIG, consistent with increased citratemia. Cessation of treatment showed a differential improvement in SIG also consistent with disposal of therapy-associated citrate. These observations might assist clinicians in interpreting acidbase changes during RCA-CVVH.in citrate infusion rate caused an alkalinizing increase in SID.


Asunto(s)
Equilibrio Ácido-Base/fisiología , Anticoagulantes/administración & dosificación , Ácido Cítrico/administración & dosificación , Soluciones para Hemodiálisis/administración & dosificación , Hemofiltración/métodos , Lesión Renal Aguda/terapia , Anciano , Enfermedad Crítica , Femenino , Humanos , Masculino , Persona de Mediana Edad
12.
Int J Artif Organs ; 31(4): 288-94, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18432583

RESUMEN

BACKGROUND: Severe hepatic failure (SHF) commonly leads to major changes in acidbase balance status. However, the direct effects of liver failure per se on acid base balance are poorly understood because this condition is usually associated with acute renal failure (ARF). AIM: To assess the effect of SHF on acid-base balance. DESIGN: Retrospective laboratory investigation. SUBJECTS: Thirty-seven critically ill patients with SHF complicated by ARF, and 42 patients with severe ARF without liver failure prior to renal replacement therapy. INTERVENTION: Retrieval of clinical and laboratory data from prospective unit and laboratory databases. METHODS: Quantitative acid-base assessment using Stewart-Figge methodology. Comparison of findings between the two groups. Comparison of demographic and clinical features. RESULTS: Patients with combined SHF and ARF were younger and had significantly higher mean bilirubin, ALT and INR levels (p<0.0001). Their mean lactate concentration was higher (6.4 vs. 2.1 mmol/L; p<0.0001) leading to a greater anion gap (25.8 vs. 16.1 mmol/L; p<0.0001). The ionized calcium concentration (1.00 vs. 1.15 mmol/L; p<0.0001) was lower but the strong ion difference apparent (SIDa) was greater (42.0 vs. 38.0 mEq/L; p<0.005) due to hypochloremia. The albumin concentration was low but higher than in control patients (28 vs. 24 g/L; p<0.01) and the calculated strong ion gap (SIG) was greater (12.6 vs. 9.3 mEq/L; p<0.01). The base excess was similar to controls and the pH was preserved in the near normal range by marked hypocapnea. CONCLUSIONS: Combined SHF and ARF is a syndrome with unique acid-base changes due mostly to lactic metabolic acidosis and, in smaller part, to the accumulation of unmeasured anions. This acidosis, like that of ARF, is attenuated by hypoalbuminemia, by a unique preservation of the SIDa due to hypochloremia, and by marked hypocapnea.


Asunto(s)
Equilibrio Ácido-Base , Acidosis Láctica/etiología , Lesión Renal Aguda/complicaciones , Fallo Hepático/complicaciones , Acidosis Láctica/fisiopatología , Lesión Renal Aguda/fisiopatología , Adulto , Anciano , Alanina Transaminasa/sangre , Bilirrubina/sangre , Dióxido de Carbono/sangre , Cloruros/sangre , Femenino , Humanos , Concentración de Iones de Hidrógeno , Hipocalcemia/etiología , Hipocalcemia/fisiopatología , Relación Normalizada Internacional , Fallo Hepático/fisiopatología , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Albúmina Sérica/metabolismo , Índice de Severidad de la Enfermedad
13.
Int J Artif Organs ; 30(12): 1083-9, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18203070

RESUMEN

OBJECTIVES: Extended intermittent dialytic techniques are increasingly being reported in the treatment of ARF in the ICU but few randomized controlled trials exist. We compared one such technique to a technique of continuous renal replacement therapy with regard to fluid removal and hemodynamics. METHODS: Sixteen critically ill patients with ARF were enrolled in a randomized controlled trial at the ICU of a tertiary hospital. We randomized eight patients to three consecutive days of treatment with either Extended Daily Dialysis with filtration (EDDf) or Continuous Veno-Venous Hemofiltration (CVVH) and compared fluid removal and hemodynamics during treatment. RESULTS: A total of 16.6 liters of fluid were removed during EDDf (830 mL/day over 20 treatment days) compared with 15.4 liters (700 ml/day over 22 treatment days) during CVVH. Median fluid removal per day was 1837 mL in the EDDf group compared with 1410 mL per day in the CVVH group, p=0.674. Median hourly fluid removal rate was 252 mL for EDDf and 128 mL for CVVH (p<0.01). Mean arterial pressure in the EDDf group was lower at two hours after starting treatment (76 mmHg vs. 94 mmHg) in the CVVH group; p= 0.031. There was no significant difference between groups for heart rate, CVP and noradrenaline dose at all time intervals measured. CONCLUSIONS: Adequate prescribed fluid removal was achieved with both techniques. However, as expected, fluid was removed at a faster rate during EDDf. This was initially associated with a lower blood pressure than during CVVH where blood pressure increased.


Asunto(s)
Lesión Renal Aguda/terapia , Hemodiafiltración/métodos , Lesión Renal Aguda/fisiopatología , Anciano , Enfermedad Crítica , Femenino , Hemodinámica/fisiología , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Factores de Tiempo , Resultado del Tratamiento
14.
Int J Artif Organs ; 29(7): 668-74, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16874671

RESUMEN

BACKGROUND: Continuous renal replacement therapy (CRRT) affects acid-base balance but the influence of severe hepatic failure (SHF) on this effect is unknown. AIM: To assess the effect of SHF on acid-base balance in patients receiving CVVH. DESIGN: Retrospective laboratory investigation. SUBJECTS: Forty patients with SHF and acute renal failure (ARF) treated with CVVH and 42 critically ill patients with severe ARF but no liver disease also treated with CVVH (controls). INTERVENTION: Retrieval of clinical and laboratory data from prospective unit and laboratory databases. METHODS: Quantitative acid-base status assessment using the Stewart-Figge methodology. Comparison of findings between the two groups. RESULTS: Although CVVH had a major effect on acid base balance in both groups, patients with SHF had a higher mean lactate concentrations (4.8 vs. 3.1 mmol/L; p<0.0005), a greater base deficit compared to controls (-1 vs. 4.1 mEq/L; p<0.0001) and a lower PaCO 2 tension (36.8 vs. 42.5 mmHg; p<0.0001), despite the use of bicarbonate replacement fluid. The acidifying effect of hyperlactatemia was slightly worsened by an increased strong ion gap (9.3 vs. 4.9 mEq/L; p<0.0001). It was, however, attenuated by an increased strong ion difference apparent (SIDa) (43.6 vs. 41.9 mEq/L; p<0.05) secondary to hypochloremia (96 vs. 100 mmol/L; p<0.0001) and by hypoalbuminemia, although hypoalbuminemia in SHF patients (26 vs. 23; p<0.005) was less pronounced than in controls. CONCLUSION: The use of CVVH does not fully correct the independent acidifying effect of liver failure on acid-base status. Increased lactate and strong ion gap values maintain a persistent base deficit despite the alkalinizing effects of hypoalbuminemia and hypochloremia. The correction of acidosis in SHF patients may require more intensive CVVH.


Asunto(s)
Equilibrio Ácido-Base , Hemofiltración , Fallo Hepático/fisiopatología , Lesión Renal Aguda/fisiopatología , Lesión Renal Aguda/terapia , Anciano , Enfermedad Crítica , Femenino , Humanos , Fallo Hepático/terapia , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
15.
Sci Rep ; 6: 28632, 2016 06 28.
Artículo en Inglés | MEDLINE | ID: mdl-27350295

RESUMEN

Recently it was demonstrated that Sr intercalation provides a new route to induce superconductivity in the topological insulator Bi2Se3. Topological superconductors are predicted to be unconventional with an odd-parity pairing symmetry. An adequate probe to test for unconventional superconductivity is the upper critical field, Bc2. For a standard BCS layered superconductor Bc2 shows an anisotropy when the magnetic field is applied parallel and perpendicular to the layers, but is isotropic when the field is rotated in the plane of the layers. Here we report measurements of the upper critical field of superconducting SrxBi2Se3 crystals (Tc = 3.0 K). Surprisingly, field-angle dependent magnetotransport measurements reveal a large anisotropy of Bc2 when the magnet field is rotated in the basal plane. The large two-fold anisotropy, while six-fold is anticipated, cannot be explained with the Ginzburg-Landau anisotropic effective mass model or flux flow induced by the Lorentz force. The rotational symmetry breaking of Bc2 indicates unconventional superconductivity with odd-parity spin-triplet Cooper pairs (Δ4-pairing) recently proposed for rhombohedral topological superconductors, or might have a structural nature, such as self-organized stripe ordering of Sr atoms.

16.
Rev Sci Instrum ; 87(11): 11D840, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27910454

RESUMEN

We have developed a compact fast neutron camera based on a stack of nuclear emulsion plates and a pinhole collimator. The camera was installed at J-port of Korea superconducting tokamak advanced research at National Fusion Research Institute, Republic of Korea. Fast neutron images agreed better with calculated ones based on Monte Carlo neutron simulation using the uniform distribution of Deuterium-Deuterium (DD) neutron source in a torus of 40 cm radius.

17.
Int J Artif Organs ; 28(3): 222-8, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15818544

RESUMEN

OBJECTIVE: To evaluate the acid-base effect of low-dose regional citrate anticoagulation (RCA) during continuous veno-venous hemofiltration (CVVH). DESIGN: Prospective observational study. SETTING: ICUs of tertiary public and private hospitals. SUBJECTS: Thirty critically ill patients with acute renal failure at risk of bleeding or with a major contraindication to heparin-CVVH and/or short filter life. METHODS: We used a commercial citrate-based fluid (11 mmol/L, sodium: 140 mmol/L, chloride: 108 mmol/L and 1 mol/L of potassium) as pre-dilution replacement fluid during CVVH. Further potassium was added according to serum potassium levels. We measured all relevant variables for acid-base analysis according to the Stewart-Figge methodology. RESULTS: Before treatment, study patients had a slight metabolic acidosis, which worsened over 6 hours of RCA-CVVH (pH from 7.39 to 7.38, p < 0.005; bicarbonate from 23.2 to 21.6 mmol/L, p < 0.0001 and base excess from -2.0 to -3.0 mEq/L, p < 0.0001) due to a significant increase in SIG (from 5.8 to 6.6 mEq/L, p < 0.05) and a decrease in SIDa (from 37.5 to 36.6 mEq/L, p < 0.05). These acidifying effects were attenuated by hypoalbuminemia and a decrease in lactate (from 1.48 to 1.34 mmol/L, p < 0.005) and did not lead to progressive acidosis. On cessation of treatment, this acidifying effect rapidly self-corrected within six hours. CONCLUSIONS: Low dose RCA-CVVH induces a mild acidosis secondary to an increased strong ion gap and decreased SIDa which fully self-corrects at cessation of therapy. Clinicians need to be aware of these effects to correctly interpret changes in acid-base status in such patients.


Asunto(s)
Equilibrio Ácido-Base/fisiología , Lesión Renal Aguda/terapia , Anticoagulantes/uso terapéutico , Ácido Cítrico/uso terapéutico , Hemofiltración/métodos , Anciano , Estudios de Cohortes , Enfermedad Crítica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos
18.
Int J Artif Organs ; 28(12): 1211-8, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16404696

RESUMEN

AIMS: To assess the safety and efficacy of two different commercial citrate containing pre-filter replacement fluids during continuous veno-venous hemofiltration (CVVH) in patients with frequent filter clotting. SETTING: Four intensive care units. PATIENTS: Sixty-three critically ill patients with acute renal failure (ARF). DESIGN: Prospective observational study. METHODS: We used a commercial citrate fluid (citrate: 11 mmol/L -fluid A) as predilution replacement for CVVH. We then changed to a new commercial citrate fluid (citrate: 14 mmol/L-fluid B) as replacement fluid and performed statistical comparisons. Replacement fluid rate was fixed at 2,000 ml/hour. RESULTS: Filter life was 12.2 hour with fluid A compared with 17.1 hour with fluid B on average (p=0.0001). Mean post filter ionized calcium concentration was 0.52 mmol/L with fluid A compared with 0.40 mmol/L with fluid B (p<0.0001). Citrate intolerance led to cessation of treatment in one patient with fluid A and one patient with fluid B. Overall ionized calcium levels were higher (A: 1.18 vs B: 1.13 mmol/L; p<0.0001) and bicarbonate was lower (A: 22.4 vs B: 24.5 mmol/L; p<0.0001) during treatment with fluid A. Alkalemia was seen in 10 patients treated with fluid A and 16 patients treated with fluid B (NS). CONCLUSIONS: We have developed a simple approach to regional citrate anticoagulation for CVVH using a commercial citrate-containing fluid as replacement fluid. Increasing citrate concentration from 11 to 14 mmol/L increased filter life while maintaining relative safety and simplicity.


Asunto(s)
Lesión Renal Aguda/terapia , Anticoagulantes/uso terapéutico , Citratos/uso terapéutico , Soluciones para Diálisis/uso terapéutico , Hemofiltración/métodos , Anciano , Distribución de Chi-Cuadrado , Enfermedad Crítica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Estadísticas no Paramétricas
19.
Rev Sci Instrum ; 86(7): 073701, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26233390

RESUMEN

Analyses of nuclear emulsion detectors that can detect and identify charged particles or radiation as tracks have typically utilized optical microscope systems because the targets have lengths from several µm to more than 1000 µm. For recent new nuclear emulsion detectors that can detect tracks of submicron length or less, the current readout systems are insufficient due to their poor resolution. In this study, we developed a new system and method using an optical microscope system for rough candidate selection and the hard X-ray microscope system at SPring-8 for high-precision analysis with a resolution of better than 70 nm resolution. Furthermore, we demonstrated the analysis of submicron-length tracks with a matching efficiency of more than 99% and position accuracy of better than 5 µm. This system is now running semi-automatically.

20.
J Clin Endocrinol Metab ; 54(4): 682-8, 1982 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7037811

RESUMEN

Little is known about changes in inactive plasma renin in various conditions or the in vivo activation mechanism of inactive renin. The effects of various factors known to stimulate or suppress renin release on active and inactive PRA were examined in normal subjects. Inactive PRA was determined as the difference between the total PRA after trypsin activation and active PRA. Concurrent measurements of urinary kallikrein excretion and plasma prekallikrein activity were performed to assess the possible role of renal or plasma kallikrein in in vivo activation of inactive renin. Short term stimulation with iv furosemide and ambulation, infusion of isoproterenol, and administration of captopril increased active PRA, but had little or no effect on inactive PRA. Sodium restriction and sodium loading, each for 4 days, induced parallel changes in active and inactive PRA. The administration of propranolol for 4 days decreased active PRA but did not change inactive PRA. There were no significant correlations between the changes in urinary kallikrein excretion and those in active PRA or in the proportion of active to total PRA after any short term treatments, except furosemide administration. Plasma prekallikrein activity was correlated with the proportion of active renin only during the long term sodium balance study. The present data suggest that the mechanisms ofr the control of inactive and active renin are different. Neither renal nor plasma kallikrein seems to be consistently involved in the in vivo activation of inactive renin.


Asunto(s)
Calicreínas/análisis , Calicreínas/orina , Precalicreína/análisis , Renina/sangre , Adulto , Captopril , Furosemida , Humanos , Isoproterenol , Locomoción , Masculino , Propranolol , Valores de Referencia , Sodio/metabolismo
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