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1.
J Child Orthop ; 18(2): 162-170, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38567038

RESUMO

Objectives: Slipped capital femoral epiphyses (SCFE) is a common pediatric hip disease with the risk of osteoarthritis and impingement deformities, and 3D models could be useful for patient-specific analysis. Therefore, magnetic resonance imaging (MRI) bone segmentation and feasibility of 3D printing and of 3D ROM simulation using MRI-based 3D models were investigated. Methods: A retrospective study involving 22 symptomatic patients (22 hips) with SCFE was performed. All patients underwent preoperative hip MR with pelvic coronal high-resolution images (T1 images). Slice thickness was 0.8-1.2 mm. Mean age was 12 ± 2 years (59% male patients). All patients underwent surgical treatment. Semi-automatic MRI-based bone segmentation with manual corrections and 3D printing of plastic 3D models was performed. Virtual 3D models were tested for computer-assisted 3D ROM simulation of patients with knee images and were compared to asymptomatic contralateral hips with unilateral SCFE (15 hips, control group). Results: MRI-based bone segmentation was feasible (all patients, 100%, in 4.5 h, mean 272 ± 52 min). Three-dimensional printing of plastic 3D models was feasible (all patients, 100%) and was considered helpful for deformity analysis by the treating surgeons for severe and moderate SCFE. Three-dimensional ROM simulation showed significantly (p < 0.001) decreased flexion (48 ± 40°) and IR in 90° of flexion (-14 ± 21°, IRF-90°) for severe SCFE patients with MRI compared to control group (122 ± 9° and 36 ± 11°). Slip angle improved significantly (p < 0.001) from preoperative 54 ± 15° to postoperative 4 ± 2°. Conclusion: MRI-based 3D models were feasible for SCFE patients. Three-dimensional models could be useful for severe SCFE patients for preoperative 3D printing and deformity analysis and for ROM simulation. This could aid for patient-specific diagnosis, treatment decisions, and preoperative planning. MRI-based 3D models are radiation-free and could be used instead of CT-based 3D models in the future.

2.
Children (Basel) ; 11(3)2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38539360

RESUMO

During puberty, the biological maturity of children of the same chronological age differs. To generate equal opportunities for talent selection in youth sports, the athlete's biological maturity should be considered. This is often assessed with a left hand and wrist radiography. Alternatively, ultrasound (US) could be advantageous, especially by avoiding ionizing radiation. This pilot study aimed to assess intrarater and interrater reliability of an experienced and a non-experienced examiner in an US-based examination of the knee in 20 healthy females (10-17 years). Epiphyseal closure at five anatomical landmarks was staged (stages 1-3) and its interrater and intrarater reliabilities were analyzed using Cohen's kappa (k). Interrater reliability of the calculation of the ossification ratio (OssR) was analyzed using the Bland-Altman method and intraclass correlation coefficients (ICCs). Interrater reliability for the stages was almost perfect for four landmarks. Interrater reliability ranged from k = 0.69 to k = 0.90. Intrarater reliability for the stages was almost perfect for four landmarks. Intrarater reliability ranged from k = 0.70 to k = 1.0. For the OssR, ICC was 0.930 and a minimal detectable change of 0.030 was determined. To conclude, experienced and non-experienced examiners can reliably assign individuals to different ossification stages and calculate an OssR using US-based imaging of the knee.

3.
ACS Omega ; 9(2): 2220-2233, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38250424

RESUMO

A series of monometallic Ag(I) and Cu(I) halide complexes bearing 2-(diphenylphosphino)pyridine (PyrPhos, L) as a ligand were synthesized and spectroscopically characterized. The structure of most of the derivatives was unambiguously established by X-ray diffraction analysis, revealing the formation of mono-, di-, and tetranuclear complexes having general formulas MXL3 (M = Cu, X = Cl, Br; M = Ag, X = Cl, Br, I), Ag2X2L3 (X = Cl, Br), and Ag4X4L4 (X = Cl, Br, I). The Ag(I) species were compared to the corresponding Cu(I) analogues from a structural point of view. The formation of Cu(I)/Ag(I) heterobimetallic complexes MM'X2L3 (M/M' = Cu, Ag; X = Cl, Br, I) was also investigated. The X-ray structure of the bromo-derivatives revealed the formation of two possible MM'Br2L3 complexes with Cu/Ag ratios, respectively, of 7:1 and 1:7. The ratio between Cu and Ag was studied by scanning electron microscopy-energy-dispersive X-ray analysis (SEM-EDX) measurements. The structure of the binuclear homo- and heterometallic derivatives was investigated using density functional theory (DFT) calculations, revealing the tendency of the PyrPhos ligands not to maintain the bridging motif in the presence of Ag(I) as the metal center.

4.
Eur J Pediatr ; 182(7): 3113-3120, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37093305

RESUMO

Correct management of infants after minor head trauma is crucial to minimize the risk to miss clinically important traumatic brain injury (ciTBI). Current practices typically involve CT or in-hospital surveillance. Cranial ultrasound (CUS) provides a radiation-free and fast alternative. This study examines the accuracy of radiologist-performed CUS to detect skull fracture (SF) and/or intracranial hemorrhage (ICH). An inconspicuous CUS followed by an uneventful clinical course would allow exclusion of ciTBI with a great certainty. This monocentric, retrospective, observational study analyzed CUS in infants (< 12 months) after minor head trauma at Bern University Children's Hospital, between 7/2013 and 8/2020. The primary outcome was the sensitivity and specificity of CUS in detecting SF and/or ICH by comparison to the clinical course and to additional neuroimaging. Out of a total of 325 patients, 73% (n = 241) had a normal CUS, 17% (n = 54) were found with SF, and ICH was diagnosed in 2.2% patients (n = 7). Two patients needed neurosurgery and three patients deteriorated clinically during surveillance. Additional imaging was performed in 35 patients. The sensitivity of CUS was 93% ([0.83, 0.97] 95% CI) and the specificity 98% ([0.95, 0.99] 95% CI). All false-negative cases originated in missed SF without clinical deterioration; no ICH was missed.  Conclusion: This study shows high accuracy of CUS in exclusion of SF and ICH, which can cause ciTBI. Therefore, CUS offers a reliable method of neuroimaging in infants after minor head trauma and gives reassurance to reduce the duration of in-hospital surveillance. What is Known: • Minor head trauma can cause clinically important traumatic brain injury in infants, and the management of these cases is a challenge for the treating physician. • Cranial ultrasound (CUS) is regularly used in neonatology, but its accuracy after head trauma in infants is controversial. What is New: • CUS performed by a trained radiologist can exclude findings related to clinically important traumatic brain injury (ciTBI) with high sensitivity and specificity. It therefore offers reassurance in the management of infants after minor head trauma.


Assuntos
Lesões Encefálicas Traumáticas , Traumatismos Craniocerebrais , Criança , Humanos , Lactente , Estudos Retrospectivos , Traumatismos Craniocerebrais/diagnóstico por imagem , Sensibilidade e Especificidade , Hemorragias Intracranianas , Progressão da Doença
5.
J Child Orthop ; 17(2): 116-125, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37034201

RESUMO

Purpose: Slipped capital femoral epiphysis is a common pediatric hip disease and was associated with femoral retroversion, but femoral version was rarely measured. Therefore, mean femoral version, mean femoral neck version, and prevalence of femoral retroversion were analyzed for slipped capital femoral epiphysis patients. Methods: A retrospective observational study evaluating preoperative hip magnetic resonance imaging of 27 patients (49 hips) was performed. Twenty-seven untreated slipped capital femoral epiphysis patients (28 slipped capital femoral epiphysis hips and 21 contralateral hips, age 10-16 years) were evaluated (79% stable slipped capital femoral epiphysis, 22 patients; 43% severe slipped capital femoral epiphysis, 12 patients). Femoral version was measured using Murphy method on magnetic resonance imaging (January 2014-December 2021, rapid bilateral 3-dimensional T1 water-only Dixon-based images of pelvis and knee). All slipped capital femoral epiphysis patients underwent surgery after magnetic resonance imaging. Results: Mean femoral version of slipped capital femoral epiphysis patients (-1° ± 15°) was significantly (p < 0.001) lower compared to contralateral side (15° ± 14°). Femoral version of slipped capital femoral epiphysis patients had significantly (p < 0.001) wider range from -42° to 35° (range 77°) compared to contralateral side (-5° to 44°, range 49°). Mean femoral neck version of slipped capital femoral epiphysis patients (6° ± 15°) was lower compared to contralateral side (11° ± 12°). Fifteen slipped capital femoral epiphysis patients (54%) had absolute femoral retroversion (femoral version < 0°). Six of the 12 hips (50%) with severe slips and 4 of the 8 hips (50%) with mild slips had absolute femoral retroversion (femoral version < 0°). Ten slipped capital femoral epiphysis patients (40%) had absolute femoral neck retroversion (femoral neck version < 0°). Conclusion: Although slipped capital femoral epiphysis patients showed asymmetrically lower femoral version compared to contralateral side, there was a wide range of femoral version, underlining the importance of patient-specific femoral version analysis on preoperative magnetic resonance imaging. Absolute femoral retroversion was prevalent in half of slipped capital femoral epiphysis patients, in half of severe slipped capital femoral epiphysis patients, and in half of mild slipped capital femoral epiphysis patients. This has implications for anterior hip impingement and for surgical treatment with in situ pinning or femoral osteotomy (e.g. proximal femoral derotation osteotomy) or other hip preservation surgery.

6.
Adv Mater ; 33(9): e2005630, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33458866

RESUMO

Organic light-emitting diodes (OLEDs) have come a long way ever since their first introduction in 1987 at Eastman Kodak. Today, OLEDs are especially valued in the display and lighting industry for their promising features. As one of the research fields that equally inspires and drives development in academia and industry, OLED device technology has continuously evolved over more than 30 years. OLED devices have come forward based on three generations of emitter materials relying on fluorescence (first generation), phosphorescence (second generation), and thermally activated delayed fluorescence (third generation). Furthermore, research in academia and industry toward the fourth generation of OLEDs is in progress. Excerpts from the history of green, orange-red, and blue OLED emitter development on the side of academia and milestones achieved by key players in the industry are included in this report.

7.
Inorg Chem ; 60(4): 2315-2332, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33464050

RESUMO

The well-known system of dinuclear Cu(I) complexes bridged by 2-(diphenylphosphino)pyridine (PyrPhos) derivatives Cu2X2L3 and Cu2X2LP2 (L = bridging ligand, P = ancillary ligand) goes along with endless variation options for tunability. In this work, the influence of substituents and modifications on the phosphine moiety of the NP-bridging ligand was investigated. In previous studies, the location of the lowest unoccupied molecular orbital (LUMO) of the copper complexes of the PyrPhos family was found to be located on the NP-bridging ligand and enabled color tuning in the whole visible spectrum. A multitude of dinuclear Cu(I) complexes based on the triple methylated 2-(bis(4-methylphenyl)phosphino)-4-methylpyridine (Cu-1b-H, Cu-1b-MeO, and Cu-1b-F) up to complexes bearing 2-(bis(4-fluorophenyl)phosphino)pyridine (Cu-6a-H) with electron-withdrawing fluorine atoms over many other variations on the NP-bridging ligands were synthesized. Almost all copper complexes were confirmed via single crystal X-ray diffraction analysis. Besides theoretical TDDFT-studies of the electronic properties and photophysical measurements, the majority of the phosphino-modified Cu(I) complexes was tested in solution-processed organic light-emitting diodes (OLEDs) with different heterostructure variations. The best results of the OLED devices were obtained with copper emitter Cu-1b-H in a stack architecture of ITO/PEDOT-PSS (50 nm)/poly-TPD (15 nm)/20 wt % Cu(I) emitter:CBP:TcTA(7:3) (45 nm)/TPBi (30 nm)/LiF(1 nm)/Al (>100 nm) with a high brightness of 5900 Cd/m2 and a good current efficiency of 3.79 Cd/A.

8.
J Pediatr Hematol Oncol ; 43(6): e804-e807, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32925396

RESUMO

The clinical course of SARS-CoV-2 infection (COVID-19) in children with hematologic malignancies is unclear. We describe the diagnosis, treatment and outcome of a 4-year-old boy with high-risk acute lymphoblastic leukemia and COVID-19. Regardless of immunosuppressive induction chemotherapy his symptoms remained moderate. He received only supportive treatment. Seroconversion occurred in a similar period as in immunocompetent adults. Despite prolonged myelosuppression he did neither acquire secondary infections nor did the treatment delay caused by the infection have a measurable negative impact on the residual disease of acute lymphoblastic leukemia. Intriguingly, residual leukemia even decreased even though he did not receive any antileukemic therapy.


Assuntos
COVID-19/complicações , Quimioterapia de Indução/métodos , Neoplasia Residual/prevenção & controle , Leucemia-Linfoma Linfoblástico de Células T Precursoras/tratamento farmacológico , SARS-CoV-2/isolamento & purificação , COVID-19/virologia , Pré-Escolar , Humanos , Masculino , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patologia , Leucemia-Linfoma Linfoblástico de Células T Precursoras/virologia
9.
Chemistry ; 27(17): 5439-5452, 2021 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-33176033

RESUMO

To develop new and flexible CuI containing luminescent substances, we extend our previous investigations on two metal-centered species to four metal-centered complexes. These complexes could be a basis for designing new organic light-emitting diode (OLED) relevant species. Both the synthesis and in-depth spectroscopic analysis, combined with high-level theoretical calculations are presented on a series of tetranuclear CuI complexes with a halide containing Cu4 X4 core (X=iodide, bromide or chloride) and two 2-(diphenylphosphino)pyridine bridging ligands with a methyl group in para (4-Me) or ortho (6-Me) position of the pyridine ring. The structure of the electronic ground state is characterized by X-ray diffraction, NMR, and IR spectroscopy with the support of theoretical calculations. In contrast to the para system, the complexes with ortho-substituted bridging ligands show a remarkable and reversible temperature-dependent dual phosphorescence. Here, we combine for the first time the luminescence thermochromism with time-resolved FTIR spectroscopy. Thus, we receive experimental data on the structures of the two triplet states involved in the luminescence thermochromism. The transient IR spectra of the underlying triplet metal/halide-to-ligand charge transfer (3 M/XLCT) and cluster-centered (3 CC) states were obtained and interpreted by comparison with calculated vibrational spectra. The systematic and significant dependence of the bridging halides was analyzed.

10.
Phys Chem Chem Phys ; 22(25): 14187-14200, 2020 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-32609106

RESUMO

The primary photo-induced processes in the mononuclear, heteroleptic Cu(i) complex [(DPEPhos)Cu(PyrTet)] (1), relevant for OLED applications, were investigated in various solvents and in solid state samples via femtosecond (fs) time resolved UV/Vis and fs time resolved mid-IR transient absorption spectroscopy (TA) with MLCT excitation around 340 nm. UV/Vis fs-TA on 1 in solution reveals (i) a severe blue-shift of excited state absorption on the time scale of a few picoseconds (τ2) that is not observed in solids, and (ii), on the time scale of several tens of picoseconds (τ3), a process with very similar dynamics in all samples. Mid-IR fs-TA in solution indicates structural changes with τ2. Transient absorption anisotropy experiments temporally resolve a viscosity-dependent change of the excited state transition dipole moment orientation with τ2, as quantitatively predicted for the relaxed S1-state via TD-DFT. The results strongly suggest flattening distortion (FD) and structural rearrangement of the PyrTet-moiety to occur on the time scale of τ2 in liquid phase, and to be suppressed in solid phase. Moreover, intersystem crossing (ISC) is assigned to the process described by τ3, in line with its direct observation via time-resolved luminescence spectroscopy on 1 by Bergmann et al. (Sci. Adv., 2016, 2, e1500889). Overall, the use of structure-sensitive methods and the direct comparison of different preparations of 1 (i.e. solution vs. solid state), are a unique basis for a clear assignment of spectro-temporal characteristics to fundamental deactivation processes such as FD and ISC.

11.
Dalton Trans ; 48(41): 15338-15357, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31573576

RESUMO

In this perspective, we review those stereoselective photocatalytic reactions that use synergy between photoredox catalysts and transition metal catalysts. In particular, we highlight the orchestrated interaction between two and more metals which not only enhance the turnover numbers, but also lead to increased selectivities. Aspects of green chemistry and sustainable developments are included. In this review, C-C, C-O, C-N and C-S forming reactions are discussed and a perspective on future developments is given.

12.
Pediatr Transplant ; 23(8): e13593, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31587463

RESUMO

Color Doppler US is a readily available imaging modality for the evaluation of liver transplants. The aim of our study was to evaluate the temporal course of color Doppler US findings in children after LTX and to investigate the effect of resolving and persisting abnormalities during follow-up on long-term outcome. All children who underwent LTX during January 2000 until December 2003 (155 LTX in 137 patients, 75 male and 62 female; mean age at LTX 4.1 ± 4.8 years; range, 0.1-16.3 years) were retrospectively evaluated. Following a predefined ultrasound protocol with prospective documentation, intraoperative, post-operative, and follow-up examinations were evaluated for color Doppler abnormalities. The time of occurrence and temporal course of the findings were recorded. Graft survival rates and graft survival times were compared. Abnormal color Doppler US examinations were noted in 98 of 155 grafts during the entire observational period (63.2%). In 57 of 98 grafts (58.2%), abnormalities were limited to the perioperative period (<30 days after LTX). Survival of grafts with transient perioperative abnormalities was similar to transplantations with regular color Doppler US examinations (graft survival rates, 80.7% vs 84.2%, P = .622; mean graft survival time, 2596.92 vs 2511.40 days, P = .67). Grafts with persisting color Doppler US abnormalities in the follow-up period (>30 days after LTX; 37/98 LTX, 37.8%) showed reduced survival compared with regular courses (graft survival rate 62.2% vs 80.7%, P = .047), indicating underlying organ-specific alterations. Standardized longitudinal evaluation during the perioperative and the follow-up period can enhance the prognostic capabilities of color Doppler US in children following LTX.


Assuntos
Transplante de Fígado , Fígado/irrigação sanguínea , Fígado/diagnóstico por imagem , Complicações Pós-Operatórias/diagnóstico por imagem , Ultrassonografia Doppler em Cores , Doenças Vasculares/diagnóstico por imagem , Adolescente , Criança , Pré-Escolar , Feminino , Sobrevivência de Enxerto , Humanos , Lactente , Fígado/cirurgia , Masculino , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
13.
Dalton Trans ; 48(41): 15687-15698, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31524902

RESUMO

Luminescent Cu(i) AlkylPyrPhos complexes with a butterfly-shaped Cu2I2 core and halogen containing ancillary ligands, with a special focus on fluorine, have been investigated in this study. These complexes show extremely high solubilities and a remarkable (photo)chemical stability in a series of solvents. A tunable emission resulting from thermally activated delayed fluorescence with high quantum yields was determined by luminescence and lifetime investigations in solvents and solids. Structures of the electronic ground states were analyzed by single crystal X-ray analysis. The structure of the lowest excited triplet state was determined by transient FTIR spectroscopy, in combination with quantum chemical calculations. With the obtained range of compounds we address the key requirement for the production of organic light emitting diodes based on solution processing.

14.
Chemistry ; 24(62): 16537-16542, 2018 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-30187988

RESUMO

Two-fold C-C cross-coupling of N-heterocyclic carbenes [NHCs; SIPr=C(NArCH2 )2 , 1; IPr=C(NArCH)2 , 2; Me-IPr=C(NArCMe)2 , 3; Ar=2,6-iPr2 C6 H3 ] with 4,4''-diiodo-p-terphenyl under Ni catalysis furnished [(SIPr)(C6 H4 )3 (SIPr)](I)2 (4), [(IPr)(C6 H4 )3 (IPr)](I)2 (5), and [(Me-IPr)(C6 H4 )3 (Me-IPr)](I)2 (6). Two-electron reduction of 4-6 with KC8 readily afforded NHC analogues of Müller's hydrocarbon (MH), [(SIPr)(C6 H4 )3 (SIPr)] (7), [(IPr)(C6 H4 )3 (IPr)] (8), and [(Me-IPr)(C6 H4 )3 (Me-IPr)] (9), respectively, as highly colored crystalline solids. Quantum chemical calculations suggested that the singlet ground state for 7-9 possesses a vertical singlet-triplet energy gap ΔES-T of -7.24 to -7.60 kcal mol-1 , which is significantly lower compared to that of the NHC analogues of Thiele's (TH) and Chichibabin's (CH) (18-38 kcal mol-1 ) hydrocarbons. Importantly, the calculated diradical character (y) of 7-9 (y≈0.6) is considerably higher compared to that of the related TH and CH (y=0.1-0.4), suggesting the open-shell singlet character of 7-9.

15.
Eur Radiol ; 27(12): 5337-5343, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28634626

RESUMO

OBJECTIVES: To compare hepatic 2D shear wave elastography (2D SWE) in children between free-breathing and breath-hold conditions, in terms of measurement agreement and time expenditure. METHODS: A cohort of 57 children (12.7±4.3 years) who underwent standardized 2D SWE between May and October 2015 were retrospectively evaluated. Liver elastograms were obtained under free-breathing and breath-hold conditions and time expenditure was measured. Median stiffness, interquartile range (IQR), and IQR/median ratio were calculated based on 12, six, and three elastograms. Results were compared using Pearson correlation coefficient, intraclass correlation coefficient (ICC), Bland-Altman analysis, and Student's t. RESULTS: Median liver stiffness under free-breathing and breath-hold conditions correlated strongly (7.22±4.5kPa vs. 7.21±4.11kPa; r=0.97, P<0.001). Time to acquire 12 elastograms with free-breathing was lower than that with breath-holding (79.3±32.5sec vs. 143.7±51.8sec, P<0.001). Results for median liver stiffness based of 12, six, and three elastograms demonstrated very high agreement for free-breathing (ICC 0.993) and for breath-hold conditions (ICC 0.994). CONCLUSIONS: Hepatic 2D SWE performed with free-breathing yields results similar to the breath-hold condition. With a substantially lower time requirement, which can be further reduced by lowering the number of elastograms, the free-breathing technique may be suitable for infants and less cooperative children not capable of breath-holding. KEY POINTS: • Hepatic 2D SWE performed with free-breathing yields results similar to breath-hold condition. • Benefit of the free-breathing approach is the substantially lower time requirement. • Lowering the number of elastograms can further reduce time expenditure. • Free-breathing 2D SWE is suitable in children with suspected liver disease.


Assuntos
Técnicas de Imagem por Elasticidade/métodos , Hepatopatias/diagnóstico , Fígado/diagnóstico por imagem , Respiração , Ultrassonografia Doppler/métodos , Adolescente , Biópsia , Suspensão da Respiração , Criança , Feminino , Humanos , Hepatopatias/fisiopatologia , Masculino , Reprodutibilidade dos Testes , Estudos Retrospectivos
16.
Eur Radiol ; 27(11): 4591-4601, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28500363

RESUMO

OBJECTIVES: To evaluate the kidneys of patients with haemolytic uraemic syndrome (HUS) using diffusion-weighted imaging (DWI) and Doppler ultrasound (US) compared with healthy controls. MATERIALS AND METHODS: Fifteen patients (mean age 33.3 years; three male; 12 female) with diarrhoea-positive HUS and 15 healthy volunteers were prospectively evaluated with DWI and Doppler US. A total apparent diffusion coefficient (ADCTOT), and ADCs predominantly reflecting microperfusion (ADCLOW) and diffusion (ADCHIGH) were calculated. Doppler US evaluated renal vascularity and flow. RESULTS: When compared with controls, kidneys affected by HUS showed reduced cortical ADC values (ADCTOT 1.79±0.22 vs. 2.04±0.1x10-3 mm2/s, P 0.001), resulting in either low corticomedullary differences (11/15 patients) or an inverted corticomedullary pattern (4/15 patients). Reduction of cortical ADC values was associated with a decrease of cortical vascularity on Doppler US (ADCTOT, P<0.001; ADCLOW, P 0.047). Kidneys with complete absence of the cortical vasculature on Doppler US (four patients) also demonstrated limited diffusion (ADCHIGH, P 0.002). Low glomerular filtration rate, requirement for haemodialysis during hospitalization, and longer duration of haemodialysis were associated with decreased cortical diffusivity (ADCTOT: P 0.04, 0.007, and <0.001, respectively). CONCLUSION: DWI shows qualitative and quantitative abnormalities in kidneys affected by HUS, thereby extending the non-invasive assessment of renal parenchymal damage. KEY POINTS: • In HUS, DWI is feasible for functional characterization of kidney involvement. • Kidneys affected by HUS showed reduced cortical diffusivity. • Decreased cortical diffusivity was associated with lower kidney function. • Requirement and duration of haemodialysis was linked to degree of cortical alterations.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Síndrome Hemolítico-Urêmica/diagnóstico , Rim/patologia , Adolescente , Adulto , Feminino , Taxa de Filtração Glomerular , Humanos , Rim/fisiopatologia , Masculino , Pessoa de Meia-Idade , Adulto Jovem
17.
J Vasc Interv Radiol ; 28(8): 1177-1183, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28549710

RESUMO

PURPOSE: To present frequency and types of complications related to silicone (SI) versus polyurethane (PUR) catheters of totally implanted venous access devices (TIVADs) placed in the upper arm. MATERIAL AND METHODS: A cohort of 2,491 consecutive patients with TIVADs implanted between 2006 and 2015 was retrospectively analyzed. Complications were classified according to SIR guidelines. Pearson χ2 test was used for categorical variables, and Student t test was used for continuous variables. Nominal P values were reported, and 2-sided P values < .05 were considered significant. RESULTS: Of 2,270 patients meeting the inclusion criteria, 538 had an SI catheter, and 1,732 had a PUR catheter. Total dwell time was 584,853 catheter days. Mean total complication rate was 12.25% (SI, 14.87%; PUR, 11.43%; P = .040). Subanalysis revealed significant differences for material failures (eg, catheter fracture [SI, 3.35%; PUR, 0.06%; P < .001] and thrombotic catheter occlusion/venous thromboses [SI, 2.79%/0.74%; PUR, 1.33%/3.17%; P < .001]) but nonsignificant differences for infections (eg, local infection and catheter-related sepsis [SI, 4.64%; PUR, 4.68%; P = 1]) or other nonthrombotic dysfunctions (eg, catheter detachment, line migration, wound dehiscence [SI, 3.35%; PUR, 2.19%; P = .179]). CONCLUSIONS: The reported data suggest different risk profiles in SI catheters compared with PUR catheters, with more material failures and thrombotic catheter occlusions in SI catheters and more venous thromboses in PUR catheters.


Assuntos
Braço , Cateterismo Venoso Central/efeitos adversos , Cateteres de Demora/efeitos adversos , Radiografia Intervencionista , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Falha de Equipamento , Feminino , Fluoroscopia , Humanos , Masculino , Pessoa de Meia-Idade , Poliuretanos , Estudos Retrospectivos , Silicones
18.
AJR Am J Roentgenol ; 208(2): 464-469, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27824502

RESUMO

OBJECTIVE: This present study reports the frequency and outcome of material failure of the silicone catheter lines of a port device implanted in the upper arm during a 5-year period. MATERIALS AND METHODS: From 2006 to 2011, a total of 553 patients had a port device implanted percutaneously in the upper arm. In the spring of 2013, several instances of material failure led to device withdrawal. At that time, 39 patients (7.1%) with the specific device in situ were still alive, and 36 of these patients agreed to removal. Linear mixed-effects models were used to analyze the log-transformed device dwell time. Random effects were modeled using group variables. The mean estimated values and their corresponding 95% CIs were reported. Nominal p values were reported, and two-sided p < 0.05 was considered to denote statistical significance. RESULTS: Among the 553 patients, material failure was noticed in 19 patients (3.4%), with a mean estimated dwell time of 243 days (95% CI, 104-570 days). Specifically, complete rupture occurred in 10 patients (1.8%) after a mean of 322 days (95% CI, 95-1089 days), partial rupture occurred in eight patients (1.4%) after a mean of 190 days (95% CI, 61-596 days), and disconnection occurred in one patient (0.2%) 8 days after device placement. CONCLUSION: The frequency of catheter line rupture was 3.4%. The mean estimated interval to rupture was less than a year, with an increasing probability of rupture noted in association with a longer dwell time. The exact cause of material failure remains unexplained, and further investigation of the mechanical properties contributing to rupture is required. Insight into the safety profile of these devices is needed to avoid potentially severe injury and improve the management of affected patients.


Assuntos
Falha de Equipamento/estatística & dados numéricos , Fluoroscopia/estatística & dados numéricos , Teste de Materiais/estatística & dados numéricos , Flebografia/estatística & dados numéricos , Silicones/química , Dispositivos de Acesso Vascular/estatística & dados numéricos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Alemanha/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
19.
Clin Nucl Med ; 39(7): 646-7, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24873782

RESUMO

We report a case of posttransplant distal limb syndrome (PTDLS) representing a rare complication in kidney transplant recipients characterized by a pain syndrome of the distal extremities. A 68-year-old man with a history of kidney transplantation presented with symmetrical and incapacitating pain in the feet and knees and underwent whole-body Tc-methylene diphosphonate (MDP) scintigraphy for further evaluation. Planar scintigraphy demonstrated marked tracer uptake in the distal femoral and tibial epiphyses, and magnetic resonance imaging showed corresponding osteoedema. Tc-MDP scintigraphy is a valuable tool for evaluation of the etiology of musculoskeletal pain and may demonstrate typical findings in case of PTDLS.


Assuntos
Osso e Ossos/diagnóstico por imagem , Extremidades/diagnóstico por imagem , Extremidades/patologia , Transplante de Rim/efeitos adversos , Medronato de Tecnécio Tc 99m , Idoso , Humanos , Masculino , Dor/diagnóstico por imagem , Cintilografia , Síndrome
20.
J Nucl Cardiol ; 20(4): 569-77, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23588862

RESUMO

BACKGROUND: The aim of this study was to correlate linear (18)F-sodium fluoride accumulation in the femoral arteries as a measure of diffuse mineral deposition in medial elastocalcinosis with cardiovascular risk factors (RFs) and calcified plaque burden (CPB). METHODS AND RESULTS: In this study, 409 patients were examined by (18)F-sodium fluoride positron emission tomography/computed tomography (PET/CT). Tracer accumulation was analyzed both qualitatively and semiquantitatively by measuring the target-to-background ratio, and compared with cardiovascular RFs and CPB. Linear (18)F-sodium fluoride accumulation was observed in 159 (38.9%) patients and correlated significantly with age (P < .0001), hypertension (P < .0001), hypercholesterolemia (P = .0003), diabetes (P = .0003), history of smoking (P = .0007), prior cardiovascular events (P = .03), and CPB (P < .0001). The prevalence of linear tracer uptake increased as the number of cardiovascular RFs increased (P < .0001). CONCLUSIONS: Linear (18)F-sodium fluoride uptake in the femoral arteries (1) provides a measure of diffuse mineral deposition, (2) demonstrates a highly significant correlation with cardiovascular RFs and CPB, and (3) is found to accumulate more frequently in patients with a high-risk profile for cardiovascular events. (18)F-sodium fluoride PET/CT may become a unique tool for in vivo visualization and quantification of ongoing calcification in large arteries.


Assuntos
Artéria Femoral/diagnóstico por imagem , Artéria Femoral/metabolismo , Radioisótopos de Flúor/farmacocinética , Fluoreto de Sódio/farmacocinética , Adulto , Idoso , Idoso de 80 Anos ou mais , Calcinose/diagnóstico por imagem , Doenças Cardiovasculares/diagnóstico por imagem , Complicações do Diabetes/diagnóstico , Feminino , Humanos , Hipercolesterolemia/complicações , Hipertensão/complicações , Masculino , Pessoa de Meia-Idade , Imagem Multimodal , Neoplasias/complicações , Neoplasias/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Prevalência , Reprodutibilidade dos Testes , Fatores de Risco , Fumar/efeitos adversos , Tomografia Computadorizada por Raios X , Adulto Jovem
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