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1.
Biochem Med (Zagreb) ; 34(2): 020802, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38665873

RESUMO

We present two cases from the neonatal department with cerebrospinal fluid examination. We revealed a striking discrepancy in polymorphonuclear (PMN) and mononuclear (MN) cell counts using conventional light microscopy in comparison with automated analyzer Sysmex XN-1000 (PMNs - 13 vs. 173x106/L, MNs - 200 vs. 67x106/L in case 1 and PMNs - 13 vs. 372x106/L, MNs - 411 vs. 179x106/L in case 2). We revealed the dominant presence of hemosiderophages in both cases in cytospin slide. Even though Sysmex XN-1000 offers fast examination with a low sample volume, there is possibility of misdiagnosis, with negative impact on the patient.


Assuntos
Microscopia , Humanos , Recém-Nascido , Microscopia/métodos , Masculino , Feminino , Neutrófilos/citologia , Neutrófilos/patologia , Líquido Cefalorraquidiano/citologia , Contagem de Leucócitos , Leucócitos Mononucleares/patologia , Leucócitos Mononucleares/citologia
2.
Life (Basel) ; 13(3)2023 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-36983963

RESUMO

BACKGROUND: Scientific studies point to a significant global vitamin D deficiency. The recommended dose of vitamin D for the adult population in Central Europe is 800-2000 IU/day. The aim of our study was to determine whether doses of 1000 IU or 2000 IU of vitamin D3 are adequate to achieve the sufficiency reference values of [25(OH)D]. METHODS: Seventy-two healthy volunteers, average age twenty-two, took part in the study. The study was conducted from October to March in order to eliminate intra-dermal vitamin D production. Vitamin D3 in an oleaginous mixture was used. The participants used either 1000 IU or 2000 IU/daily for two 60-day periods with a 30-day break. RESULTS: The dose of 1000 IU, taken for 60 days, increased vitamin D levels relatively little. Furthermore, serum vitamin D levels decreased in the 30 days following the cessation of supplementation. Taking 2000 IU daily led to a sharp increase in serum levels which plateaued 30 days after the subjects stopped using vitamin D3 drops. CONCLUSIONS: Both doses, taken daily, can help maintain adequate vitamin D levels during the winter months. A daily dose of 2000 IU, however, maintained the desired levels of vitamin D for a longer period.

3.
Artigo em Inglês | MEDLINE | ID: mdl-36628561

RESUMO

AIM: We present two cases with clearly discrepant results of clinical examination and cardiac troponin I (cTnI) and cardiac troponin T (cTnT) concentrations. In similar cases with discrepant results, the possibility of interference should be considered. METHODS: Due to the suspicion of the presence of macrotroponin I in both of the presented cases, the patients were invited to our laboratory and both cTnI (Architect i1000, Abbott) and cTnT (Cobas 8000, Roche) concentrations were analysed. The samples were treated by preincubation in a heterophilic antibodies blocking tube (HBT) and analysed. Precipitation with polyethylene glycol solution (PEG) and molecular weight separation by gel filtration on Sephadex G100 was performed and concentrations of cTnI were analysed. RESULTS: In the same blood sample, the cTnT and cTnI concentrations were 7 and 1782 ng/L, respectively, in Case 1, and 6 and 96 ng/L, respectively, in Case 2. Incubation of samples in HBT had no significant effect. CTnI concentrations after precipitation with PEG - presented as the percentage of initial concentrations - were 7.4% in Case 1 (and 26.8% in the control sample) and 1.4% in Case 2 (and 56.0% in the control sample). These results indicate a significant decrease in both cases, supporting presence of macrotroponin I. Finally, analyses of cTnI concentrations after gel filtration also supported the presence of macrotroponin I. CONCLUSION: The present cases show that the presence of macrotroponin can lead to unnecessary investigation of the patient. When the possibility of interference is suspected, cooperation with laboratory staff to help with interpretation or to perform more detailed analysis is crucial.

4.
J Med Biochem ; 40(3): 277-285, 2021 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-34177372

RESUMO

BACKGROUND: To compare four automated immunoassays for the measurement of 25(OH)-vitamin D (25-OHD) and to assess the impact on the results obtained from a healthy population. METHODS: We analysed 100 serum samples on Unicel DxI 800 (Beckman Coulter), Architect i1000 (Abbott), Cobas e411 (Roche) and Liaison XL (DiaSorin). Passing-Bablok regression and Bland-Altman plots were used for method comparison. In order to categorise the obtained values, results were categorised into the following groups: 0-25 nmol/L, 25-50 nmol/L, 50-75 nmol/L and above 75 nmol/L and compared. The percentage of samples below 75 nmol/L, and below 50 nmol/L was then calculated for every method. RESULTS: According to paired comparisons, each method differs from others (p<0.0001) except Cobas vs Architect, which do not show a statistically significant difference (p=0.39). The strongest correlation was found between Liaison and Architect (ρ=0.94, p<0.0001). The percentage of samples below the recommended value of 75 nmol/L were: 70% (Architect), 92% (Liaison), 71% (Cobas) and 89% (Unicel). The percentage of samples below the value of 50 nmol/L were: 17% (Architect), 55% (Liaison), 28% (Cobas) and 47% (Unicel). CONCLUSIONS: The observed differences stem from the use of different analytical systems for 25-OHD concentration analysis and can result in different outcomes. The recommended values should be established for each assay in accordance with the data provided by the manufacturer or in the laboratory, in accordance with proper standardisation.

5.
Swiss Med Wkly ; 149: w20166, 2019 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-31869428

RESUMO

AIM OF THE STUDY: The objective of this study was to identify the optimal duration of pharmacological thromboprophylaxis after outpatient endovenous laser ablation (EVLA). METHODS: In this multicentre retrospective study in a university hospital, regional hospital and private practices, we collected the demographic, procedural and outcome data of all consecutive patients with varicose veins class C2 to C6 undergoing outpatient EVLA of truncal and accessory veins between February 2009 and December 2015. The cumulative primary efficacy endpoint consisted of endovenous heat-induced thrombosis (EHIT) class 2–4, deep vein thrombosis (DVT) and pulmonary embolism (PE) diagnosed with duplex ultrasound or computed tomography angiography after 1 and 4 weeks of follow-up. Cumulative secondary endpoints were complete ablation of the treated veins and major bleeding, skin burns and infection. RESULTS: A total of 864 patients were treated with EVLA as an outpatient procedure. Of those, 35 patients were omitted because of therapeutic anticoagulation or dual antiplatelet therapy. Another 36 cases were excluded as the patients received pharmacological thromboprophylaxis for 5 days. A total of 793 were included in the final analysis. Of those, 225 patients (28.4%) received fondaparinux 2.5 mg s.c. for 3 days, 166 patients (20.9%) received rivaroxaban 10 mg p.o. for 3 days and 402 patients (50.7%) received rivaroxaban 10 mg for 10 days. The incidence of EHIT class 2–4 was 0.8% (n = 6) in total, 1.3% (n = 6) in group 1 (treated for 3 days) and 0.3% (n = 1) in group 2 (treated for 10 days) (odds ratio [OR] 0.19, confidence interval [CI] 0.02–1.66, p = 0.133). The cumulative primary composite endpoint at 4-week follow-up was 1.1% (n = 9) and was 2.1% (n = 8) in group 1 and 0.3% (n = 1) in group 2 (OR 0.0.12, CI 0.01–0.96, p = 0.046). Propensity score-matched analysis revealed no significant difference in the composite primary endpoint (CI −0.074 to 0.26). Complete occlusion rate was 99.2% in group 1 and 98.8% in group 2 (OR 0.61, CI 0.15–2.59, p = 0.506). No PE or major bleeding events occurred in either group. Propensity score-matched analysis showed no significant difference in the secondary endpoints. CONCLUSION: Using propensity score-matched analysis we showed that pharmacological thromboprophylaxis after EVLA seems to be equally effective with 3 days or 10 days of treatment with a similar success rate and safety profile. Undoubtedly, a large randomised control trial, ideally including a group without pharmacological thromboprophylaxis, is needed to draw more definitive conclusions on the optimal duration of pharmacological post-EVLA thromboprophylaxis.


Assuntos
Inibidores do Fator Xa/administração & dosagem , Fondaparinux/administração & dosagem , Terapia a Laser , Rivaroxabana/administração & dosagem , Tromboembolia Venosa/prevenção & controle , Procedimentos Cirúrgicos Ambulatórios , Relação Dose-Resposta a Droga , Esquema de Medicação , Procedimentos Endovasculares , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pontuação de Propensão , Estudos Retrospectivos , Veia Safena/cirurgia , Varizes/cirurgia
6.
Swiss Med Wkly ; 149: w20083, 2019 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-31154658

RESUMO

AIMS OF THE STUDY: The purpose of this study was to evaluate the safety and efficacy of endovenous laser ablation (EVLA) in patients 75 years and older in an outpatient setting. METHODS: In this multicentre retrospective study, we collected the demographic, procedural and outcome data of all consecutive patients with varicose veins class C2 to C6 undergoing EVLA of truncal and accessory saphenous veins. The primary efficacy endpoint was complete ablation of the treated veins diagnosed with duplex ultrasound at 4-week follow up. The primary safety endpoint was endothermal heat-induced thrombosis (EHIT) and deep vein thrombosis (DVT) at 4-week follow up as diagnosed by duplex ultrasound. A secondary endpoint was minor or major bleeding. RESULTS: Between February 2009 and December 2015, a total of 829 patients were treated with EVLA of the truncal and accessory saphenous veins. Among them, 747 were <75 years old (group 1) and 82 were ≥75 years old (group 2). The primary efficacy outcome was reached in 739 patients (98.9%) in group 1 and in 80 patients (97.6%) in group 2 (odd ratio [OR] 0.43, confidence interval [CI] 0.09–2.07; p = 0.295). The number of patients with EHIT type 2 and DVT were 4 (0.5%) and 2 (0.3%), respectively, in group 1, and 2 (2.4%) and 1 (1.2%), respectively, in group 2 (OR 4.64, CI 0.83–25.75; p = 0.079 and OR 4.59, CI 0.41–51.27; p = 0.215, respectively). Minor bleeding events occurred in 36 patients (4.8%) in group 1 and 7 patients (8.9%) in group 2 (OR 1.84, CI 0.79-4.29; p = 0.155). No major bleeding occurred in either group. Propensity score-matched analysis revealed no significant difference in efficacy and safety outcomes. CONCLUSION: EVLA performed as an outpatient procedure seems to be effective and safe in the elderly population as compared to the younger age group.


Assuntos
Procedimentos Cirúrgicos Ambulatórios/estatística & dados numéricos , Procedimentos Endovasculares/estatística & dados numéricos , Terapia a Laser/estatística & dados numéricos , Varizes/cirurgia , Idoso , Idoso de 80 Anos ou mais , Procedimentos Cirúrgicos Ambulatórios/efeitos adversos , Procedimentos Cirúrgicos Ambulatórios/métodos , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/métodos , Feminino , Humanos , Terapia a Laser/efeitos adversos , Terapia a Laser/métodos , Masculino , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Pontuação de Propensão , Estudos Retrospectivos , Veia Safena/cirurgia , Suíça , Resultado do Tratamento , Trombose Venosa/epidemiologia , Trombose Venosa/etiologia
7.
RSC Adv ; 9(37): 21451-21459, 2019 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-35521323

RESUMO

The temperature and phase stability of p-type skutterudites, DD0.7Fe3CoSb12, manufactured via various preparation techniques, all exhibiting a high ZT-level, have been studied by means of thermal analysis and Knudsen effusion mass spectrometry. The results from phase transformation measurements and characteristics of the evaporation of antimony, as the volatile element, supported by microstructure observations and by diffusion profiles are summarized and discussed in view of a full understanding of the degradation processes and knowledge of the long term operation stability of the bulk and nano-structured thermoelectrics studied. It was found out that the antimony evaporation is a complex diffusion kinetic process resulting in a stable Sb level dependent on the preparation route. The studied p-type skutterudites, DD0.7Fe3CoSb12, have proven their long term stability in thermoelectric devices at a maximum operation temperature of 600 °C. Complementary data on the structural, physical and mechanical properties of the materials are presented as well.

8.
J Med Biochem ; 37(3): 364-372, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30598634

RESUMO

BACKGROUND: The aim of this study was to examine high-sensitivity troponin T and I (hsTnT and hsTnI) after a treadmill run under laboratory conditions and to find a possible connection with echocardiographic, laboratory and other assessed parameters. METHODS: Nineteen trained men underwent a standardized 2-hour-long treadmill run. Concentrations of hsTnT and hsTnI were assessed before the run, 60, 120 and 180 minutes after the start and 24 hours after the run. Changes in troponins were tested using non-parametric analysis of variance (ANOVA). The multiple linear regression model was used to find the explanatory variables for hsTnT and hsTnI changes. Values of troponins were evaluated using the 0h/1h algorithm. RESULTS: Changes in hsTnT and hsTnI levels were statistically significant (p<0.0001 and p<0.0001, respectively). In a multiple regression model (adjusted R2: 0.60, p=0.005 for hsTnT and adjusted R2: 0.60, p=0.005 for hsTnI), changes in both troponins can be explained by relative left wall thickness (LV), training volume, body temperature after the run and creatinine changes. According to the 0h/1h algorithm, none of the runners was evaluated as negative. CONCLUSIONS: Relative LV wall thickness, creatinine changes, training volume and body temperature after the run can predict changes in hsTnT and hsTnI levels. When medical attention is needed after physical exercise, hsTn levels should be tested only when clinical suspicion and the patient's history indicate a high probability of myocardial damage.

9.
J Vasc Surg Venous Lymphat Disord ; 5(4): 515-523, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28623988

RESUMO

OBJECTIVE: Endovenous heat-induced thrombosis (EHIT) is a well-described complication of endovenous laser ablation (EVLA). We report our centers' experience on the efficacy (EHIT level ≥2 according to the Kabnick classification) and safety (observed major and minor bleeding events) of rivaroxaban for EHIT prophylaxis in EVLA with and without concomitant phlebectomy. METHODS: Demographic, procedural, and outcome data of all patients with EVLA of the great, accessory, or small saphenous vein and EHIT prophylaxis with 10 mg/d rivaroxaban between 2012 and 2014 were reviewed and analyzed in this investigator-initiated multicenter retrospective observational single-arm study. RESULTS: During a median (interquartile range) follow-up duration of 51 (41-68) days, complete vein occlusion was achieved in 98.4% of 438 EVLA procedures in 306 patients. One patient had an EHIT level 2 (0.2%; 95% confidence interval, 0.006%-1.3%). No major bleedings (0%; 95% confidence interval, 0.0%-0.8%) and six minor bleedings (1.4%; 95% confidence interval, 0.5%-3%) were observed. CONCLUSIONS: Rivaroxaban (10 mg/d) for 5 to 10 days seems to be an efficacious and safe alternative for EHIT prophylaxis in EVLA with or without phlebectomy.


Assuntos
Inibidores do Fator Xa/administração & dosagem , Terapia a Laser/efeitos adversos , Rivaroxabana/administração & dosagem , Trombose/prevenção & controle , Varizes/cirurgia , Insuficiência Venosa/cirurgia , Adulto , Idoso , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Veia Poplítea/cirurgia , Complicações Pós-Operatórias/prevenção & controle , Estudos Retrospectivos , Fatores de Risco , Veia Safena/cirurgia , Suíça , Trombose/etiologia , Fatores de Tempo , Resultado do Tratamento , Ultrassonografia Doppler Dupla , Varizes/diagnóstico por imagem , Procedimentos Cirúrgicos Vasculares/métodos , Insuficiência Venosa/diagnóstico por imagem
10.
Vasa ; 46(5): 325-336, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28447881

RESUMO

Lower extremities varicose veins are among the most frequent diseases in the general population. They can cause complaints with a deterioration of the quality of life and are associated with potentially threatening clinical conditions such as chronic venous ulceration, haemorrhage from ruptured varicose veins, and venous thromboembolism. An accurate diagnostic work-up is crucial to confirm the presence and the extension of the venous problem, in order to obtain an optimal management of the condition. In the past years, great efforts have been made to reach an international consensus on the terminology, the symptomatology, the classification, and the duplex ultrasound examination of lower extremities varicose veins. Mainly guided by these consensus documents, the present article describes the diagnostic work-up of lower extremities varicose veins, based on a careful medical history, physical examination, and duplex ultrasound examination.


Assuntos
Extremidade Inferior/irrigação sanguínea , Ultrassonografia Doppler Dupla , Varizes/diagnóstico por imagem , Veias/diagnóstico por imagem , Doença Crônica , Humanos , Valor Preditivo dos Testes , Prognóstico , Fluxo Sanguíneo Regional , Reprodutibilidade dos Testes , Varizes/fisiopatologia , Varizes/terapia , Veias/fisiopatologia
11.
Clin Chem Lab Med ; 55(1): 47-52, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-27362961

RESUMO

BACKGROUND: Pneumatic tube systems (PTS) are widely used in many hospitals. Using PTS reduces turnaround time (TAT) and can improve patients' outcome. METHODS: We investigated whether clinically significant differences could be observed in CSF samples transported by pneumatic tube in comparison with samples transported by hand. Two aliquots from one sample were sent by PTS and by hand from the department of neurology or neurosurgery and compared. RESULTS: Routine cytological and biochemical assessment was compared in 27 cases. There were no statistically significant changes (transport by hand vs. PTS) in glucose levels [data are expressed as median (minimum-maximum)] at 3.7 (2.5-8.6) mmol/L vs. 3.6 (2.7-8.6) mmol/L, p=0.96 or lactate levels at 1.8 mmol/L (1.1-5.5) vs. 1.8 mmol/L (1.1-5.4). We observed a statistically significant decline in total protein levels in samples transported by PTS at 0.56 g/L (0.19-4.29) vs. 0.49 g/L (0.18-4.3), p=0.008. We observed no changes in erythrocyte count at 5/µL (0-40,000) vs. 5/µL (0-40,106), mononuclear cells at 2/µL (1-145) vs. 3/µL (1-152), or polynuclear cells at 0/µL (0-235) vs. 0/µL (0-352). Spectrophotometric examination was performed in 20 cases. There were no statistically significant differences (transport by hand vs. transport by PTS) in NOA at 0.002 (0.001-1.537) vs. 0.001 (0.001-1.528), p=0.95 or NBA at 0.001 (0.001-0.231) vs. 0.001 (0.001-0.276), p=0.675. Samples transported by PTS were delivered faster than samples transported by courier (transport by hand vs. PTS) at 25 min (10-153) vs. 15 min (4-110), p=0.002. CONCLUSIONS: We found no significant changes in glucose, lactate levels and in any of the cytological parameters assessed, nor were statistically significant changes observed in the spectrophotometric parameters. We found a statistically significant decrease in total protein levels in samples transported by PTS. Transport by PTS can be faster than transport by hand.


Assuntos
Coleta de Amostras Sanguíneas/instrumentação , Líquido Cefalorraquidiano/química , Líquido Cefalorraquidiano/citologia , Contagem de Eritrócitos , Humanos , Contagem de Leucócitos , Espectrofotometria/instrumentação , Fatores de Tempo
12.
Ultraschall Med ; 38(1): 14-32, 2017 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-27737471

RESUMO

Part one addressed the value of duplex ultrasound in the diagnostic workup of varicosis. The present article discusses the use of preinterventional, intrainterventional and postinterventional duplex ultrasound in endoluminal methods for the treatment of varices. It is a prerequisite for the planning, implementation, and follow-up of this form of therapy.


Assuntos
Angioplastia/métodos , Ultrassonografia Doppler Dupla/métodos , Varizes/diagnóstico por imagem , Varizes/terapia , Seguimentos , Humanos , Resultado do Tratamento , Varizes/classificação , Insuficiência Venosa/classificação , Insuficiência Venosa/diagnóstico por imagem , Insuficiência Venosa/terapia
13.
Praxis (Bern 1994) ; 105(14): 813-9, 2016 Jul 06.
Artigo em Alemão | MEDLINE | ID: mdl-27381305

RESUMO

Venous leg symptoms are frequent, but their relevance is frequently underestimated. With the introduction of effective, minimal-invasive endovenous treatment modalities the treatment of varicose veins has recently made major advances. The basis of every treatment decision is a competent anamnesis, clinical investigation and duplex scan. Outpatient varicose vein treatment using endovenous methods has been proofed to be at least as effective as traditional varicose vein surgery but is associated with fewer adverse events. Accordingly, the endovenous methods are exspected to replace surgery as goldstandard treatment and endovenous thermal vein ablation (Laser/Radiofrequency) is accepted by the Swiss Federal Office of Public Health for general reimbursment since 1st january 2016. All currently available methods have their advantages and limitations, the individual selection based on the present symptoms, anatomic findings and patients' preferences is fundamental for an optimal treatment result and maximized patient satisfaction.


Assuntos
Varizes/terapia , Assistência Ambulatorial , Ablação por Cateter , Procedimentos Endovasculares/métodos , Humanos , Terapia a Laser , Escleroterapia/métodos , Meias de Compressão , Ultrassonografia Doppler Dupla , Ultrassonografia de Intervenção , Varizes/diagnóstico por imagem
14.
Phys Chem Chem Phys ; 17(42): 28277-85, 2015 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-25929324

RESUMO

Solvothermal synthesis was used for Ag-Cu nanoparticle (NP) preparation from metallo-organic precursors. The detailed NP characterization was performed to obtain information about nanoparticle microstructure and both phase and chemical compositions. The resulting nanoparticles exhibited chemical composition inside a FCC_Ag + FCC_Cu two-phase region. The microstructure study was performed by various methods of electron microscopy including high-resolution transmission electron microscopy (HRTEM) at an atomic scale. The HRTEM and X-ray diffraction studies showed that the prepared nanoparticles form the face centred cubic (FCC) crystal lattice where the silver atoms are randomly mixed with copper. The CALPHAD approach was used for predicting the phase diagram of the Ag-Cu system in both macro- and nano-scales. The predicted spinodal decomposition of the metastable Ag-Cu nanoparticles was experimentally induced by heating on an X-ray powder diffractometer (HT XRD). The nucleation of the Cu-rich phase was detected and its growth was studied. Changes in the Ag-rich phase were observed in situ by X-ray diffraction under vacuum. The heat treatment was conducted at different maximum temperatures up to 450 °C and the resulting particle product was analysed. The experiments were complemented by differential scanning calorimetry (DSC) measurements up to liquidus temperature. The start temperatures of the spinodal phase transformation and particle aggregation were evaluated.

15.
Clin Hemorheol Microcirc ; 60(3): 263-71, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-23370157

RESUMO

We assessed the cutaneous microcirculatory reactivity of a clinically unaffected skin region in patients with systemic sclerosis (SSc) compared to healthy controls by measuring transcutaneous oxygen saturation (TcPO2) and Laser Doppler flowmetry (LDF).Twelve consecutive patients with SSc and twelve healthy controls were subjected to TcPO2 monitoring and LDF during cuff-induced ischemia and reactive hyperemia in order to measure the skin oxygen tension and the microcirculatory blood flow. Mean minimal and maximal values of oxygen tension and blood flow, time to peak (TTP), and declining slopes after peaking (slope) were compared between patients with SSc and controls.Compared to the controls, TcPO2 values in SSc were similar during ischemia and diminished during reactive hyperemia, with longer TTP, and a slower return to baseline (-60% vs. -58% , p = 1.000, +76% vs. +210% , p = 0.047, 137 s vs. 108 s, p = 0.028, -0.009% /s vs. -0.019% /s, p = 0.021, respectively). LDF values, however, did not differ significantly between patients with SSc and controls.Unaffected skin regions of SSc patients showed a significantly diminished postischemic vasodilatory reactivity when assessed by TcPO2 monitoring, but not by LDF, indicating that vasculopathy may represent an early mechanism in the onset of skin sclerosis. TcPO2 measurement may help to detect changes in the microcirculation in SSc with no skin affection.


Assuntos
Fluxometria por Laser-Doppler/métodos , Microcirculação/fisiologia , Oximetria/métodos , Oxigênio/sangue , Escleroderma Sistêmico/sangue , Pele/irrigação sanguínea , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Fisiológica/métodos
16.
J Magn Reson Imaging ; 40(6): 1408-13, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24338875

RESUMO

PURPOSE: To investigate the origin of skeletal muscle BOLD MRI alterations in patients with systemic sclerosis (SSc) by correlating BOLD MRI T2* signal of calf muscles with microcirculatory blood flow of calf skin measured by laser Doppler flowmetry (LDF). MATERIALS AND METHODS: BOLD MRI (3T) and LDF measurements were performed in 12 consecutive SSc patients (6 women, 6 men; mean age 54.0 ± 10.0 years) and 12 healthy volunteers (4 men, 8 women; mean age 44.7 ± 13.1 years). For both modalities, the same cuff compression paradigm at mid-thigh level was used. LDF datasets were acquired using a PeriScan PIM II Imager (Perimed AB, Stockholm, Sweden) at the upper calf corresponding to the level of MR imaging. Cross-correlations of BOLD and LDF signal intensity changes depending on time lags between both time series were calculated. RESULTS: Maximal cross-correlations of BOLD T2* and LDF measurements were calculated as 0.93 (healthy volunteers) and 0.94 (SSc patients) for a BOLD time lag of approximately 10 s. Key parameter analysis suggested that in contrast to hyperemic BOLD signal loss at maximum value in SSc patients, ischemic T2* decrease cannot be explained by differences of tissue perfusion. CONCLUSION: Skeletal muscle BOLD T2* signal in SSc patients is closely correlated with changes of microperfusion as detected by LDF.


Assuntos
Fluxometria por Laser-Doppler/métodos , Angiografia por Ressonância Magnética/métodos , Músculo Esquelético/irrigação sanguínea , Oxigênio/sangue , Escleroderma Sistêmico/fisiopatologia , Pele/irrigação sanguínea , Adulto , Velocidade do Fluxo Sanguíneo , Feminino , Humanos , Masculino , Músculo Esquelético/diagnóstico por imagem , Oximetria/métodos , Reprodutibilidade dos Testes , Escleroderma Sistêmico/diagnóstico , Sensibilidade e Especificidade , Pele/diagnóstico por imagem , Estatística como Assunto , Ultrassonografia
17.
J Magn Reson Imaging ; 38(4): 845-51, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23441019

RESUMO

PURPOSE: To prospectively compare calf muscle BOLD MRI with transcutaneous oxygen pressure (TcPO2 ) measurement in patients with systemic sclerosis (SSc) and healthy volunteers and thereby get insight into the pathogenesis of vasculopathy in this connective tissue disorder. MATERIALS AND METHODS: Twelve patients with SSc (6 women and 6 men, mean age 53.5 ± 10.0 years) and 12 healthy volunteers (4 men and 8 women, mean age 47 ± 12.1 years) were examined using muscle BOLD MRI and TcPO2. A cuff compression at mid-thigh level was performed to provoke ischemia and reactive hyperemia. BOLD measurements were acquired on a 3 Tesla whole body-scanner in the upper calf region using a multi-echo EPI-sequence with four echo-times (TE: 9/20/31/42 ms) and a repetition time of 2 s. Empirical cross-correlation analysis depending on time lags between BOLD- and TcPO2-measurements was performed. RESULTS: Maximal cross-correlation of BOLD T2*- and TcPO2-measurements was calculated as 0.93 (healthy volunteers) and 0.90 (SSc patients) for a time lag of approximately 40 s. Both modalities showed substantial differences regarding time course parameters between the SSc patients and healthy volunteers. CONCLUSION: Skeletal muscle BOLD MRI correlated very well with TcPO2 . T2* changes seem to reflect reoxygenation deficits in deeper muscle tissue of SSc patients.


Assuntos
Isquemia/patologia , Imageamento por Ressonância Magnética , Microcirculação , Oxigênio/metabolismo , Escleroderma Sistêmico/metabolismo , Escleroderma Sistêmico/patologia , Adulto , Estudos de Casos e Controles , Interpretação Estatística de Dados , Feminino , Humanos , Perna (Membro)/patologia , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/patologia , Pressão , Estudos Prospectivos , Projetos de Pesquisa
18.
Arthritis Res Ther ; 14(5): R209, 2012 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-23036642

RESUMO

INTRODUCTION: Muscle symptoms in systemic sclerosis (SSc) may originate from altered skeletal muscle microcirculation, which can be investigated by means of blood oxygenation level dependent (BOLD) magnetic resonance imaging (MRI). METHODS: After ethics committee approval and written consent, 11 consecutive SSc patients (5 men, mean age 52.6 years, mean SSc disease duration 5.4 years) and 12 healthy volunteers (4 men, mean age 45.1 years) were included. Subjects with peripheral arterial occlusive disease were excluded. BOLD MRI was performed on calf muscles during cuff-induced ischemia and reactive hyperemia, using a 3-T whole-body scanner (Verio, Siemens, Erlangen, Germany) and fat-suppressed single-short multi-echo echo planar imaging (EPI) with four different effective echo times. Muscle BOLD signal time courses were obtained for gastrocnemius and soleus muscles: minimal hemoglobin oxygen saturation (T2*min) and maximal T2* values (T2*max), time to T2* peak (TTP), and slopes of oxygen normalization after T2* peaking. RESULTS: The vast majority of SSc patients lacked skeletal muscle atrophy, weakness or serum creatine kinase elevation. Nevertheless, more intense oxygen desaturation during ischemia was observed in calf muscles of SSc patients (mean T2*min -15.0%), compared with controls (-9.1%, P = 0.02). SSc patients also had impaired oxygenation during hyperemia (median T2*max 9.2% vs. 20.1%, respectively, P = 0.007). The slope of muscle oxygen normalization was significantly less steep and prolonged (TTP) in SSc patients (P<0.001 for both). Similar differences were found at a separate analysis of gastrocnemius and soleus muscles, with most pronounced impairment in the gastrocnemius. CONCLUSIONS: BOLD MRI demonstrates a significant impairment of skeletal muscle microcirculation in SSc.


Assuntos
Microcirculação/fisiologia , Músculo Esquelético/irrigação sanguínea , Músculo Esquelético/patologia , Escleroderma Sistêmico/fisiopatologia , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Hiperemia/patologia , Hiperemia/fisiopatologia , Isquemia/patologia , Isquemia/fisiopatologia , Perna (Membro)/irrigação sanguínea , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Oxigênio/sangue , Escleroderma Sistêmico/patologia
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