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1.
Hamostaseologie ; 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38991541

RESUMO

Chronic venous disease (CVD) is highly prevalent in the general population and encompasses a range of pathological and hemodynamic changes in the veins of the lower extremities. These alterations give rise to a variety of symptoms, with more severe forms resulting in venous ulceration, which causes morbidity and high socioeconomic burden. The origins and underlying mechanisms of CVD are intricate and multifaceted, involving environmental factors, genetics, hormonal factors, and immunological factors that bring about structural and functional alterations in the venous system. This review offers the latest insights into the epidemiology, pathophysiology, and risk factors of CVD, aiming to provide a comprehensive overview of the current state of knowledge. Furthermore, the diagnostic approach for CVD is highlighted and current diagnostic tools are described.

2.
Res Pract Thromb Haemost ; 8(4): 102464, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-39006228

RESUMO

Background: Venous thromboembolism (VTE) is associated with various long-term complications. Objectives: We aimed to investigate the association of clinical characteristics at VTE diagnosis with functional limitations 3 and 12 months afterward. Methods: We conducted a prospective cohort study of VTE patients, excluding patients with cancer, pregnancy, and postpartum period. Functional limitations were assessed with the post-VTE functional status (PVFS) scale (range, 0-4) within 21 days of diagnosis, after 3 and 12 months (prospectively), and 1 month before diagnosis (retrospectively). Twelve-month follow-up was only performed in patients on anticoagulation. We fitted 2 proportional odds logistic regression models for the 3- and 12-month follow-ups and computed odds ratios (ORs) with 95% bootstrap percentile confidence intervals (CIs). Results: We included 307 patients (42% female, median age 55.6 years) with a median (IQR) PVFS scale grade of 2 (2-3) at study inclusion and 0 (0-0) before diagnosis. After 3 months, PVFS scale grade in 269 patients was 1 (0-2). Female sex (OR, 2.15; 95% CI, 1.26-4.14), body mass index (OR per 1 kg/m2 increase, 1.05; 95% CI, 1.00-1.10), functional limitations at baseline, and older age were associated with functional limitations. After 12 months, PVFS scale grade in 124 patients was 1 (0-2). Female sex (OR, 4.47; 95% CI, 2.11-16.00), history of cardiovascular/pulmonary disease (OR, 2.36; 95% CI, 1.01-6.89), and functional limitations at baseline were associated with functional limitations. Conclusion: Functional limitations in VTE patients improved 3 and 12 months after diagnosis but did not return to pre-VTE values. We identified clinical characteristics that could help identify patients at risk of persisting functional limitations after VTE.

3.
Acta Derm Venereol ; 104: adv40090, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38813744

RESUMO

Martorell hypertensive ischaemic leg ulcer (Martorell HYTILU) is a rare but significant cause of distal leg ulcers. Although hypertension and diabetes are known factors in its development, the precise pathogenesis of Martorell HYTILU remains elusive. To reach a better understanding of Martorell HYTILU, transcriptomic analysis was conducted through RNA sequencing and immunohistochemical comparison of Martorell HYTILU (n = 17) with chronic venous ulcers (n = 4) and healthy skin (n = 4). Gene expression analysis showed a marked activation of immune-related pathways in both Martorell HYTILU and chronic venous ulcers compared with healthy skin. Notably, neutrophil activity was substantially higher in Martorell HYTILU. While pathway analysis revealed a mild downregulation of several immune pathways in Martorell HYTILU compared with chronic venous ulcers, keratinization, cornification, and epidermis development were significantly upregulated in Martorell HYTILU. Additionally, STAC2, a gene encoding for a protein promoting the expression of the calcium channel Cav1.1, was significantly upregulated in Martorell HYTILU and was detected perivascularly in situ (Martorell HYTILU n = 24; chronic venous ulcers n = 9, healthy skin n = 11). The high expression of STAC2 in Martorell HYTILU suggests that increased calcium influx plays an important role in the pathogenesis of the disease. Consequently, calcium channel antagonists could be a promising treatment avenue for Martorell HYTILU.


Assuntos
Hipertensão , Úlcera Varicosa , Humanos , Masculino , Feminino , Úlcera Varicosa/imunologia , Idoso , Doença Crônica , Hipertensão/complicações , Hipertensão/genética , Pessoa de Meia-Idade , Pele/patologia , Pele/imunologia , Isquemia/genética , Isquemia/imunologia , Perfilação da Expressão Gênica , Transcriptoma , Estudos de Casos e Controles , Úlcera da Perna/etiologia , Úlcera da Perna/imunologia , Idoso de 80 Anos ou mais
4.
Pract Lab Med ; 39: e00382, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38463194

RESUMO

Objectives: The direct approach for determining reference intervals (RIs) is not always practical. This study aimed to generate evidence that a real-world data (RWD) approach could be applied to transfer free thyroxine RIs determined in one population to a second population, presenting an alternative to performing multiple RI determinations. Design and methods: Two datasets (US, n = 10,000; Europe, n = 10,000) were created from existing RWD. Descriptive statistics, density plots and cumulative distributions were produced for each data set and comparisons made. Cumulative probabilities at the lower and upper limits of the RIs were identified using an empirical cumulative distribution function. According to these probabilities, estimated percentiles for each dataset and estimated differences between the two sets of percentiles were obtained by case resampling bootstrapping. The estimated differences were then evaluated against a pre-determined acceptance criterion of ≤7.8% (inter-individual biological variability). The direct approach was used to validate the RWD approach. Results: The RWD approach provided similar descriptive statistics for both populations (mean: US = 16.1 pmol/L, Europe = 16.4 pmol/L; median: US = 15.4 pmol/L, Europe = 15.8 pmol/L). Differences between the estimated percentiles at the upper and lower limits of the RIs fulfilled the pre-determined acceptance criterion and the density plots and cumulative distributions demonstrated population homogeneity. Similar RI distributions were observed using the direct approach. Conclusions: This study provides evidence that a RWD approach can be used to transfer RIs determined in one population to another.

5.
Res Pract Thromb Haemost ; 8(1): 102324, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38419653

RESUMO

Background: Data on walking impairment during the acute phase of deep vein thrombosis (DVT) are limited. Objectives: This study aimed to assess the degree of walking impairment in patients with acute DVT, with a particular focus on the relation to the DVT's anatomical location. Methods: Patients with sonographically confirmed DVT were eligible for inclusion in this cohort study. Pain-free walking distance (PWD) and maximum walking distance (MWD) were determined using standardized treadmill ergometer tests and analyzed in relation to DVT location. The impact of previous DVT on walking capacity was evaluated in an exploratory analysis. Results: The study included 64 patients (31% women; median age, 55 years). The median (IQR) time from diagnosis to exercise test was 3 (1-5) days. Patients with suprainguinal DVT demonstrated significantly shorter median (IQR) MWD than those with infrainguinal DVT (130 (61-202) m vs 565 (128-750) m; P < .01), while PWD did not significantly differ (PWD: 20 (0-30) m vs 40 (0-222) m; P = .14). The proportion of patients who had to terminate treadmill tests prematurely was higher in patients with suprainguinal DVT (91.7% vs 57.7%; P = .04). PWD and MWD seemed to be similar in patients with and without a history of DVT. Premature test termination and suprainguinal DVT location were associated with reduced quality of life, as measured by the EuroQoL Group 5-Dimension 5-Level questionnaire and visual analog scale. Conclusion: Suprainguinal DVT was linked to a more pronounced walking impairment compared with infrainguinal DVT. Limited walking capacity was associated with a reduced quality of life.

6.
Dermatopathology (Basel) ; 11(1): 62-78, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38390849

RESUMO

Ulcerations of the lower extremities are a frequently encountered problem in clinical practice and are of significant interest in public health due to the high prevalence of underlying pathologies, including chronic venous disease, diabetes and peripheral arterial occlusive disease. However, leg ulcers can also present as signs and symptoms of various rare diseases and even as an adverse reaction to drugs. In such cases, correct diagnosis ultimately relies on histopathological examination. Apart from the macroscopic presentation, patient history and anatomic location, which are sometimes indicative, most ulcers have very distinct histopathological features. These features are found in different layers of the skin or even associated vessels. In this narrative review, we discuss and highlight the histopathological differences of several types of leg ulcers that can contribute to efficient and accurate diagnosis.

8.
J Dtsch Dermatol Ges ; 21(11): 1339-1349, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37658661

RESUMO

BACKGROUND: Diagnostic work-up of leg ulcers is time- and cost-intensive. This study aimed at evaluating ulcer location as a diagnostic criterium and providing a diagnostic algorithm to facilitate differential diagnosis. PATIENTS AND METHODS: The study consisted of 277 patients with lower leg ulcers. The following five groups were defined: Venous leg ulcer, arterial ulcers, mixed ulcer, arteriolosclerosis, and vasculitis. Using computational surface rendering, predilection sites of different ulcer types were evaluated. The results were integrated in a multinomial logistic regression model to calculate the likelihood of a specific diagnosis depending on location, age, bilateral involvement, and ulcer count. Additionally, neural network image analysis was performed. RESULTS: The majority of venous ulcers extended to the medial malleolar region. Arterial ulcers were most frequently located on the dorsal aspect of the forefoot. Arteriolosclerotic ulcers were distinctly localized at the middle third of the lower leg. Vasculitic ulcers appeared to be randomly distributed and were markedly smaller, multilocular and bilateral. The multinomial logistic regression model showed an overall satisfactory performance with an estimated accuracy of 0.68 on unseen data. CONCLUSIONS: The presented algorithm based on ulcer location may serve as a basic tool to narrow down potential diagnoses and guide further diagnostic work-up.


Assuntos
Úlcera da Perna , Úlcera Varicosa , Humanos , Úlcera , Úlcera da Perna/diagnóstico , Úlcera da Perna/etiologia , Úlcera Varicosa/diagnóstico , Perna (Membro) , Algoritmos
9.
J Vasc Surg Cases Innov Tech ; 9(2): 101113, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37013067

RESUMO

Venous valve aplasia (or valvular rarefication) is a rare cause of chronic venous insufficiency. In the present report, we have described the case of a 33-year-old man with severe symmetric lower leg edema and heaviness and pain in both lower legs. Duplex ultrasound demonstrated severe venous insufficiency in the superficial and deep venous system of both legs. Further imaging examinations supported the diagnosis of venous valvular aplasia. Treatment consisted of endovenous thermal ablation of the great saphenous vein and small saphenous vein as well as consistent compression therapy, resulting in a marked reduction of his leg edema, heaviness, and pain.

10.
Hum Vaccin Immunother ; 19(1): 2199653, 2023 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-37067070

RESUMO

COVID-19 vaccine-related adverse events are mostly minor to moderate, and serious events are rare. Single cases of Raynaud's phenomenon (RP) in temporal proximity to COVID-19 vaccination have been reported. Demographic data, medical history, and detailed information regarding vaccination status and RP characteristics were obtained from patients with confirmed RP after COVID-19 vaccination. Fifteen participants reported the initial manifestation of RP, which occurred in 40% after the first, in 33% after the second, and in 27% after the third vaccination. RP development and occurrence of episodes were not linked to any specific vaccine type. New onset of disease was observed in 40% of the vaccinees after BNT162b2, in 33% after mRNA-1273, and in 27% after ChAdOx1 vaccination. Three out of four participants with preexisting RP prior to COVID-19 vaccination reported aggravation in frequency and intensity after immunization. Although COVID-19 vaccination is pivotal in controlling the pandemic, the observed temporal association between vaccine administration and RP occurrence warrants global activities to support pharmacovigilance for the detection of adverse reactions, one of which may include RP.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Doença de Raynaud , Humanos , Vacina BNT162 , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , Doença de Raynaud/diagnóstico , Vacinação/efeitos adversos
11.
J Patient Rep Outcomes ; 7(1): 28, 2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36920629

RESUMO

BACKGROUND: The Venous Clinical Severity Score (VCSS) and the Venous Disability Score (VDS) represent assessment tools for chronic venous disease (CVD) combining physician and patient reported outcomes. To date, German versions are not available. The present study aimed at translating the VCSS and VDS into German and validating the questionnaires. METHODS: Translations of VCSS and VDS were compiled based on published guidelines considering potential differences in the use of German language in different countries. For validation, 33 patients with chronic venous disease and 5 healthy individuals were included in the pre-testing phase. Patients were examined twice by independent investigators to validate test-retest-validity culminating in 142 limb examinations. Internal consistency, inter-rater dependence and external reliability were subsequently evaluated. RESULTS: All assessed metrics showed good internal consistency. Intra-class correlation coefficients were .75 for the VDS, .98 for the VCSS of the right leg and .90 for the VCSS of the left leg, indicating inter-rater independence. Furthermore, VCSS scores showed a modest positive correlation with CEAP C class and both VCSS and VDS showed a negative correlation with the physical component of the SF-12, indicating adequate external reliability. CONCLUSION: A pan-cultural German version of both the VCSS and VDS was established and validated as reliable tools to evaluate the severity of CVD in German speaking countries.


Assuntos
Comparação Transcultural , Doenças Vasculares , Humanos , Reprodutibilidade dos Testes , Veias , Tradução , Doença Crônica
12.
Thromb Res ; 221: 1-6, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36427439

RESUMO

BACKGROUND: A large proportion of patients experience functional limitations after an acute episode of venous thromboembolism (VTE). Recently, the post-VTE functional status (PVFS) scale was proposed to capture these limitations. We performed a prospective cohort study to validate this scale. METHODS: The PVFS scale, PROMIS physical function 10a, EQ-5D-5L, and disease-specific quality of life (VEINES-QOL/Sym, PEmb-QoL) were assessed within three weeks of VTE diagnosis and after a median (IQR) follow-up of 13.4 (12.7-15.9) weeks. To evaluate construct validity of the PVFS scale, we determined correlations of PVFS scale with the other health measurements and investigated differences in patients above/below 70 years. Responsiveness was evaluated with a linear regression model, predicting change in PROMIS with change in PVFS scale. RESULTS: We included 211 patients (median (IQR) age: 55.1 (44.1-67.6) years, 40 % women). Pulmonary embolism was diagnosed in 105 (49.8 %) patients and 62.6 % of events were unprovoked. The PVFS scale correlated with PROMIS physical function (Spearman's rho (r): -0.67 and -0.63, p < 0.001) and EQ-5D-5L index (r = -0.61 and -0.61, p < 0.001) at baseline and follow-up. Furthermore, PVFS correlated moderately to strongly with disease-specific quality of life. Patients >70 years had significantly higher PVFS grades at follow-up (median (IQR): 2 (0-3) vs. 1 (0-2), p = 0.010). Changes in PVFS scale over time were significantly associated with changes in PROMIS physical function. CONCLUSIONS: The PVFS scale showed adequate construct validity and responsiveness in a prospective cohort study of patients with VTE, suggesting that it can be incorporated as additional health measurement and outcome parameter in research and clinical practice.


Assuntos
Qualidade de Vida , Tromboembolia Venosa , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Tromboembolia Venosa/diagnóstico , Estudos Prospectivos , Estado Funcional , Psicometria , Inquéritos e Questionários
13.
Wound Repair Regen ; 30(2): 198-209, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35043507

RESUMO

In an ageing society, chronic ulcers pose an increasingly relevant healthcare issue associated with significant morbidity and an increasing financial burden. Hence, there is an unmet medical need for novel, cost-effective therapies that improve healing of chronic cutaneous wounds. This prospective, randomised, open-label, phase I trial investigated the safety and tolerability of topically administered purified clinoptilolite-tuff (PCT), mainly consisting of the naturally occurring zeolite-mineral clinoptilolite, in artificial wounds in healthy male volunteers compared to the standard of care (SoC). We found that topically administered PCT was safe for therapeutic application in acute wounds in healthy male volunteers. No significant differences in wound healing or wound conditions were observed compared to SoC-treated wounds. However, we found a significantly higher proportion of CD68-positive cells and a significantly lower proportion of α-smooth muscle actin-positive cells in PCT-treated wounds. Scanning electron microscopy revealed PCT particles in the restored dermis in some cases. However, these did not impede wound healing or clinical symptoms. Hence, purified PCT could represent an attractive, cost-effective wound treatment promoting the process of healing.


Assuntos
Lesões dos Tecidos Moles , Zeolitas , Humanos , Masculino , Estudos Prospectivos , Cicatrização/fisiologia , Zeolitas/farmacologia
14.
Dermatol Ther ; 35(4): e15322, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35040545

RESUMO

Endovenous thermal and non-thermal therapeutic approaches have become standard of care for the treatment of venous insufficiency. However, comparative studies on its use in the population of venous leg ulcer patients are scarce. The present study aimed at a comparison of the efficacy of endovenous laser ablation (EVLA) and ultrasound-guided foam sclerotherapy (UGFS) for the treatment of venous leg ulcers (VUs). We retrospectively analyzed patient records of 68 patients with active VUs (C6 of the CEAP-classification), who underwent EVLA (n = 33) or UGFS (n = 35) between January 2001 and January 2021. In 68 patients, 97 venous segments (GSV: 43, SSV: 17, NSV: 37) were treated. Ulcer surface area at initial presentation did not differ significantly between both treatment groups (EVLA: 7.7 ± 10.7 vs. UGFS: 8.5 ± 16.3 cm2 ; p = 0.73). No significant difference regarding patient characteristics was found, with the exception of age, as patients receiving UGFS treatment were significantly older (EVLA: 61 ± 17 vs. UGFS: 70 ± 14 years; p = 0.018). The rate of ulcer resolution was not significantly different between EVLA and UGFS groups (97.0% vs. 85.7%; p = 0.20). Also, the mean time to complete ulcer healing after endovenous intervention was comparable (EVLA: 59 ± 37 vs. UGFS: 63 ± 41 days; p = 0.68). However, the relapse rate was significantly higher for UGFS than for EVLA treated patients (31.4% vs. 3.0%; p = 0.002). Taken together, rates of ulcer resolution and ulcer healing time after endovenous intervention were comparable between both treatment modalities. Nevertheless, a significantly higher relapse rate was observed in UGFS treated patients.


Assuntos
Terapia a Laser , Úlcera da Perna , Varizes , Insuficiência Venosa , Humanos , Terapia a Laser/efeitos adversos , Estudos Retrospectivos , Veia Safena/cirurgia , Escleroterapia/efeitos adversos , Resultado do Tratamento , Ultrassonografia de Intervenção , Varizes/etiologia , Varizes/cirurgia , Insuficiência Venosa/diagnóstico por imagem , Insuficiência Venosa/etiologia , Insuficiência Venosa/terapia
15.
Photodermatol Photoimmunol Photomed ; 38(2): 104-111, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34351641

RESUMO

BACKGROUND: The aim of this retrospective study was to compare the efficacy and safety of different phototherapeutic modalities in the treatment of cutaneous lichen planus (LP). METHODS: We retrospectively analyzed the chart data of 53 patients with generalized LP who had been subjected to narrowband UVB (NB-UVB) or photochemotherapy (PUVA) between January 1997 and April 2020. Of these, 30 patients had received NB-UVB, 18 patients oral PUVA and 5 patients bath PUVA. RESULTS: Fifty patients completed a full treatment course. The percentage of patients with a complete (>90% clearing) or good (51%-90% clearing) response was similar for NB-UVB versus PUVA (86.2% vs. 90.5%; P = 1.00). The number of exposures required for obtaining a complete or good response was also comparable for both treatment groups (NB-UVB: 28.9 ± 12.3 vs. PUVA: 25.4 ± 10.1; P = .209). Adverse events, in particular gastrointestinal upsets, were recorded in 26.1% of patients treated with oral PUVA while none were observed with NB-UVB. CONCLUSION: The therapeutic outcome and the number of treatments required for achieving a complete or good response were comparable for NB-UVB and PUVA; however, PUVA therapy was associated with a substantially higher rate of moderate adverse events.


Assuntos
Líquen Plano , Fotoquimioterapia , Terapia Ultravioleta , Ficusina/uso terapêutico , Humanos , Líquen Plano/tratamento farmacológico , Terapia PUVA , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/uso terapêutico , Fototerapia , Estudos Retrospectivos , Resultado do Tratamento , Terapia Ultravioleta/efeitos adversos , Terapia Ultravioleta/métodos
16.
Case Rep Dermatol ; 13(3): 450-456, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34720917

RESUMO

Herein, we report a case of a new-onset Raynaud's phenomenon (RP), which occurred in an otherwise healthy 31-year-old Caucasian woman, who lacked any known risk factors and associations with possible causes for secondary RP. However, 2 weeks prior to the development of RP, the patient had received her first injection of the COVID-19 vaccine containing ChAdOx1-SARS-COV-2. The patient presented with well-demarcated, white-pale, cold areas involving the middle fingers of both hands and the ring finger of the right hand, which were triggered by exposure to cold environment and accompanied by a sensation of numbness. Infrared thermography revealed notable temperature differences of up to 10.9°C between affected and nonaffected fingers. Coagulation and immunological parameters, including cryoglobulins and pathological autoantibodies, were within the normal range and antibodies to the heparin/platelet factor 4 complex not detectable. It remains unclear if the development of RP in our patient is causally related to antecedent COVID-19 vaccination; however, the temporal connection to the vaccination, the complete absence of RP in her past medical history, and the lack of any risk factors and triggers raise the suspicion of a yet unknown association with the vaccine. Whether a clear association between the development of RP and COVID-19 vaccination exists or whether RP represents a bystander effect needs to be awaited in case observational reports on RP accumulate. Given the steadily rising numbers of people receiving COVID-19 vaccinations, physicians may remain alert to still unrecognized side effects.

18.
J Cell Sci ; 134(17)2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34345888

RESUMO

Dysfunction of vascular barriers is a critical step in inflammatory diseases. Endothelial tight junctions (TJs) control barrier function, and the cytoplasmic adaptor protein cingulin connects TJs to signalling pathways. However, local events at TJs during inflammation are largely unknown. In this study, we investigate the local response of TJ adaptor protein cingulin and its interaction with Rho guanine nucleotide exchange factor H1 (GEF-H1, also known as ARHGEF2) upon vascular barrier disruption to find a new approach to counteract vascular leak. Based on transendothelial-electrical-resistance (TEER) measurements, cingulin strengthened barrier integrity upon stimulation with histamine, thrombin and VEGF. Cingulin also attenuated myosin light chain 2 (MLC2; also known as MYL2) phosphorylation by localising GEF-H1 to cell junctions. By using cingulin phosphomutants, we verified that the phosphorylation of the cingulin head domain is required for its protective effect. Increased colocalisation of GEF-H1 and cingulin was observed in the vessels of vasculitis patients compared to those in healthy skin. Our findings demonstrate that cingulin can counteract vascular leak at TJs, suggesting the existence of a novel mechanism in blood endothelial cells that protects barrier function during disease.


Assuntos
Células Endoteliais , Junções Íntimas , Permeabilidade Capilar , Células Endoteliais/metabolismo , Fatores de Troca do Nucleotídeo Guanina/genética , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Humanos , Fatores de Troca de Nucleotídeo Guanina Rho/genética , Fatores de Troca de Nucleotídeo Guanina Rho/metabolismo , Transdução de Sinais , Junções Íntimas/metabolismo
19.
Acta Derm Venereol ; 101(5): adv00449, 2021 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-33856037

RESUMO

Clinical differential diagnosis of arteriolosclerotic ulcers of Martorell is challenging due to the lack of clearly affirmative instrument-based diagnostic criteria. The aim of this study was to develop vascular histomorphological diagnostic criteria differentiating Martorell ulcers from other types of leg ulcers. The histomorphology of patients diagnosed with arteriolosclerotic ulcers of Martorell (n = 67) was compared with that of patients with venous leg ulcers, necrotizing leukocytoclastic vasculitis, pyoderma gangrenosum, and non-ulcerative controls (n = 15 each). In a multivariable logistic regression model, the rates of arteriolar calcification (odds ratio (OR) 42.71, 95% confidence interval (CI) 7.43-443.96, p < 0.001) and subendothelial hyalinosis (OR 29.28, 95% CI 4.88-278.21, p <0.001) were significantly higher in arteriolosclerotic ulcers of Martorell. Arteriolar cellularity was significantly lower in Martorell ulcers than in controls (OR 0.003, 95 CI < 0.001-0.97, p = 0.05). However, the wall-to-lumen ratio was similar in all ulcers (OR 0.975, 95% CI 0.598-2.04, p =0.929). Based on the Youden index, a wall cellularity of < 0.24 cells/100 µm2 was determined as the optimum cut-off point (sensitivity 0.955, specificity 0.944). Thus, arteriolar calcification, subendothelial hyalinosis, and arteriolar cellularity revealed high discriminatory power for arteriolosclerotic ulcers of Martorell.


Assuntos
Úlcera da Perna , Úlcera , Diagnóstico Diferencial , Humanos , Úlcera da Perna/diagnóstico
20.
J Biol Chem ; 296: 100334, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33508322

RESUMO

Systemic light chain (AL) amyloidosis is a fatal protein misfolding disease in which excessive secretion, misfolding, and subsequent aggregation of free antibody light chains eventually lead to deposition of amyloid plaques in various organs. Patient-specific mutations in the antibody VL domain are closely linked to the disease, but the molecular mechanisms by which certain mutations induce misfolding and amyloid aggregation of antibody domains are still poorly understood. Here, we compare a patient VL domain with its nonamyloidogenic germline counterpart and show that, out of the five mutations present, two of them strongly destabilize the protein and induce amyloid fibril formation. Surprisingly, the decisive, disease-causing mutations are located in the highly variable complementarity determining regions (CDRs) but exhibit a strong impact on the dynamics of conserved core regions of the patient VL domain. This effect seems to be based on a deviation from the canonical CDR structures of CDR2 and CDR3 induced by the substitutions. The amyloid-driving mutations are not necessarily involved in propagating fibril formation by providing specific side chain interactions within the fibril structure. Rather, they destabilize the VL domain in a specific way, increasing the dynamics of framework regions, which can then change their conformation to form the fibril core. These findings reveal unexpected influences of CDR-framework interactions on antibody architecture, stability, and amyloid propensity.


Assuntos
Amiloide/ultraestrutura , Regiões Determinantes de Complementaridade/genética , Amiloidose de Cadeia Leve de Imunoglobulina/genética , Placa Amiloide/genética , Sequência de Aminoácidos/genética , Amiloide/genética , Amiloide/imunologia , Proteínas Amiloidogênicas/genética , Proteínas Amiloidogênicas/imunologia , Proteínas Amiloidogênicas/ultraestrutura , Regiões Determinantes de Complementaridade/química , Regiões Determinantes de Complementaridade/ultraestrutura , Humanos , Amiloidose de Cadeia Leve de Imunoglobulina/imunologia , Amiloidose de Cadeia Leve de Imunoglobulina/metabolismo , Mutação/genética , Placa Amiloide/imunologia , Placa Amiloide/patologia , Agregação Patológica de Proteínas/genética , Agregação Patológica de Proteínas/imunologia , Agregação Patológica de Proteínas/patologia , Conformação Proteica , Dobramento de Proteína
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