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1.
Acta Neuropathol ; 147(1): 15, 2024 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-38214778

RESUMO

Histopathological analysis stands as the gold standard for the identification and differentiation of inflammatory neuromuscular diseases. These disorders continue to constitute a diagnostic challenge due to their clinical heterogeneity, rarity and overlapping features. To establish standardized protocols for the diagnosis of inflammatory neuromuscular diseases, the development of cost-effective and widely applicable tools is crucial, especially in settings constrained by limited resources. The focus of this review is to emphasize the diagnostic value of major histocompatibility complex (MHC) and complement patterns in the immunohistochemical analysis of these diseases. We explore the immunological background of MHC and complement signatures that characterize inflammatory features, with a specific focus on idiopathic inflammatory myopathies. With this approach, we aim to provide a diagnostic algorithm that may improve and simplify the diagnostic workup based on a limited panel of stainings. Our approach acknowledges the current limitations in the field of inflammatory neuromuscular diseases, particularly the scarcity of large-scale, prospective studies that validate the diagnostic potential of these markers. Further efforts are needed to establish a consensus on the diagnostic protocol to effectively distinguish these diseases.


Assuntos
Miosite , Doenças Neuromusculares , Humanos , Estudos Prospectivos , Doenças Neuromusculares/diagnóstico , Complexo Principal de Histocompatibilidade , Antígenos de Histocompatibilidade Classe I/análise
2.
Arch Gynecol Obstet ; 310(1): 277-284, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38492082

RESUMO

PURPOSE: Myasthenia gravis (MG) is a rare, potentially life-threatening autoimmune disease with fluctuating muscle weakness frequently affecting women of childbearing age. MG can affect maternal as well as neonatal outcome with risk of worsening of myasthenic symptoms in the mothers and risk of transient neonatal myasthenia gravis (TNMG) and arthrogryposis multiplex congenita (AMC) or foetal acetylcholine receptor antibody-associated disorders (FARAD) in the neonates. METHODS: Retrospective analysis of maternal and neonatal outcome in a cohort of pregnant MG patients treated at a tertiary care centre in Germany. RESULTS: Overall, 66 pregnancies were analysed. During 40 (63%) pregnancies, women experienced a worsening of myasthenic symptoms, of whom 10 patients (15.7%) needed acute therapy with IVIg or plasma exchange. There was no case of myasthenic crisis. Rate of caesarean section was comparable to the overall C-section rate at our centre (38% vs. 40%). However, there was a slightly higher rate for operative vaginal delivery (15% vs. 10%) as potential indicator for fatiguing striated musculature in MG patients during the expulsion stage. Rate of TNMG as well as AMC was 3% (two cases each). CONCLUSIONS: Maternal and neonatal outcome in our cohort was favourable with a low rate of myasthenic exacerbations requiring acute therapies and a low rate of TNMG and AMC/FARAD. Our data might help neurologists and obstetricians to advice MG patients with desire to have children.


Assuntos
Miastenia Gravis , Complicações na Gravidez , Resultado da Gravidez , Centros de Atenção Terciária , Humanos , Feminino , Gravidez , Estudos Retrospectivos , Miastenia Gravis/epidemiologia , Miastenia Gravis/terapia , Adulto , Centros de Atenção Terciária/estatística & dados numéricos , Alemanha/epidemiologia , Recém-Nascido , Complicações na Gravidez/epidemiologia , Resultado da Gravidez/epidemiologia , Imunoglobulinas Intravenosas/uso terapêutico , Cesárea/estatística & dados numéricos , Troca Plasmática , Miastenia Gravis Neonatal/epidemiologia , Adulto Jovem
3.
Nervenarzt ; 95(4): 316-328, 2024 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-38499774

RESUMO

BACKGROUND: There is evidence that gender-specific differences can influence the diagnostics, treatment and long-term disease course of myasthenia gravis (MG). In women the diagnosis is often made during childbearing age. OBJECTIVE: Gender-specific differences in MG and relevant aspects in routine clinical practice are presented. In addition, current studies on family planning, pregnancy and childbirth in MG are highlighted and treatment recommendations are derived. MATERIAL AND METHODS: Narrative literature review. RESULTS: In addition to sociodemographic data, gender-specific differences encompass clinical as well as paraclinical factors, such as disease severity and antibody status. With few exceptions pregnancy is possible with good maternal and neonatal outcome. During pregnancy and peripartum, children of MG patients should be closely monitored for early detection and treatment of potential syndromes caused by diaplacental transfer of maternal antibodies. CONCLUSION: Gender-specific factors can influence the course of MG. Adequate medical counselling and multidisciplinary collaboration are essential for MG patients who wish to have children.


Assuntos
Miastenia Gravis , Complicações na Gravidez , Gravidez , Criança , Recém-Nascido , Humanos , Feminino , Serviços de Planejamento Familiar , Miastenia Gravis/diagnóstico , Miastenia Gravis/terapia , Autoanticorpos , Família , Complicações na Gravidez/diagnóstico , Complicações na Gravidez/terapia
4.
J Rheumatol ; 50(2): 236-239, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36182106

RESUMO

OBJECTIVE: Musculoskeletal ultrasound (MSUS) is increasingly being used in the evaluation of pediatric musculoskeletal diseases. In order to provide objective assessments of arthritis, reliable MSUS scoring systems are needed. Recently, joint-specific scoring systems for arthritis of the pediatric elbow, wrist, and finger joints were proposed by the Childhood Arthritis and Rheumatology Research Alliance (CARRA) MSUS workgroup. This study aimed to assess the reliability of these scoring systems when used by sonographers with different levels of expertise. METHODS: Members of the CARRA MSUS workgroup attended training sessions for scoring the elbow, wrist, and finger. Subsequently, scoring exercises of B mode and power Doppler (PD) mode still images for each joint were performed. Interreader reliability was determined using 2-way single-score intraclass correlation coefficients (ICCs) for synovitis and Cohen [Formula: see text] for tenosynovitis. RESULTS: Seventeen pediatric rheumatologists with different levels of MSUS expertise (1-15 yrs) completed a 2-hour training session and calibration exercise for each joint. Excellent reliability (ICC > 0.75) was found after the first scoring exercise for all the finger and elbow views evaluated on B mode and PD mode, and for all of the wrist views on B mode. After a second training session and a scoring exercise, the wrist PD mode views reached excellent reliability as well. CONCLUSION: The preliminary CARRA MSUS scoring systems for assessing arthritis of the pediatric elbow, wrist, and finger joints demonstrate excellent reliability among pediatric MSUS sonographers with different levels of expertise. With further validation, this reliable joint-specific scoring system could serve as a clinical tool and scientific outcome measure.


Assuntos
Artrite Juvenil , Punho , Humanos , Criança , Articulações dos Dedos , Cotovelo , Reprodutibilidade dos Testes , Ultrassonografia/métodos , Articulações/diagnóstico por imagem
5.
Neuroepidemiology ; 57(2): 121-128, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36807212

RESUMO

BACKGROUND: Myasthenia gravis (MG) is a rare chronic autoimmune disease caused by autoantibodies directed against postsynaptic antigens of the neuromuscular junction. Over the last decades, increasing incidence and prevalence rates have been reported. Epidemiological data on prevalence and incidence in Germany are lacking. Furthermore, the MG treatment landscape is rapidly changing due to the continued approval of novel monoclonal antibodies. METHOD: This is a retrospective study assessing incidence, prevalence, and hospitalization rates of MG as well as treatment patterns in Germany over 10 years based on medical claims data covering 6.1 million insured persons. RESULTS: Between 2011 and 2020, the prevalence rate of MG increased from 15.7 to 28.2 per 100,000 person-years. The age-adjusted incidence rate was 2.8 per 100,000 person-years within the study period (95% confidence interval, 2.43-3.22) and decreased dramatically in 2020, the year of the COVID-19 pandemic. Similarly, the hospitalization rate fluctuated within the study period but reached an overall low of 8.3% in 2020 (mean hospitalization rate 11.5%). Treatment patterns showed that most MG patients are treated with base therapy. However, crisis intervention is necessary for 2-5% of MG patients, and therapeutic monoclonal antibodies, including rituximab and eculizumab, are increasingly used. CONCLUSION: This is the first study on MG prevalence and incidence rates in Germany. Data show an increase in prevalence by 1.8-fold over 10 years. Decreasing incidence and hospitalization rates in 2020 hint at the impact of the COVID-19 pandemic. Treatment patterns in MG are changing with the advent of therapeutic monoclonal antibodies in this indication.


Assuntos
COVID-19 , Miastenia Gravis , Humanos , Incidência , Estudos Retrospectivos , Prevalência , Pandemias , COVID-19/epidemiologia , Miastenia Gravis/tratamento farmacológico , Miastenia Gravis/epidemiologia , Anticorpos Monoclonais/uso terapêutico , Análise de Dados
6.
Eur J Neurol ; 30(5): 1409-1416, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36752022

RESUMO

BACKGROUND AND PURPOSE: Complement component 5 (C5) targeting therapies are clinically beneficial in patients with acetylcholine receptor antibody+ (AChR-Ab+ ) generalized myasthenia gravis (MG). That clearly implicates antibody-mediated complement activation in MG pathogenesis. Here, classical and alternative complement pathways were profiled in patients from different MG subgroups. METHODS: In a case-control study, concentrations of C3a, C5a and sC5b9 were simultaneously quantified, indicating general activation of the complement system, whether via the classical and lectin pathways (C4a) or the alternative pathway (factors Ba and Bb) in MG patients with AChR or muscle-specific kinase antibodies (MuSK-Abs) or seronegative MG compared to healthy donors. RESULTS: Treatment-naïve patients with AChR-Ab+ MG showed substantially increased plasma levels of cleaved complement components, indicating activation of the classical and alternative as well as the terminal complement pathways. These increases were still present in a validation cohort of AChR-Ab+ patients under standard immunosuppressive therapies; notably, they were not evident in patients with MuSK-Abs or seronegative MG. Neither clinical severity parameters (at the time of sampling or 1 year later) nor anti-AChR titres correlated significantly with activated complement levels. CONCLUSIONS: Markers indicative of complement activation are prominently increased in patients with AChR-Ab MG despite standard immunosuppressive therapies. Complement inhibition proximal to C5 cleavage should be explored for its potential therapeutic benefits in AChR-Ab+ MG.


Assuntos
Autoanticorpos , Ativação do Complemento , Miastenia Gravis , Receptores Colinérgicos , Humanos , Autoanticorpos/imunologia , Estudos de Casos e Controles , Ativação do Complemento/imunologia , Proteínas do Sistema Complemento/análise , Proteínas do Sistema Complemento/imunologia , Miastenia Gravis/classificação , Miastenia Gravis/tratamento farmacológico , Miastenia Gravis/imunologia , Receptores Colinérgicos/imunologia , Via Alternativa do Complemento , Via Clássica do Complemento , Masculino , Feminino , Adulto Jovem , Adulto , Pessoa de Meia-Idade
7.
Acta Neuropathol ; 144(2): 353-372, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35612662

RESUMO

Anti-synthetase syndrome (ASyS)-associated myositis is a major subgroup of the idiopathic inflammatory myopathies (IIM) and is characterized by disease chronicity with musculoskeletal, dermatological and pulmonary manifestations. One of eight autoantibodies against the aminoacyl-transferase RNA synthetases (ARS) is detectable in the serum of affected patients. However, disease-specific therapeutic approaches have not yet been established.To obtain a deeper understanding of the underlying pathogenesis and to identify putative therapeutic targets, we comparatively investigated the most common forms of ASyS associated with anti-PL-7, anti-PL-12 and anti-Jo-1. Our cohort consisted of 80 ASyS patients as well as healthy controls (n = 40), diseased controls (n = 40) and non-diseased controls (n = 20). We detected a reduced extent of necrosis and regeneration in muscle biopsies from PL-12+ patients compared to Jo-1+ patients, while PL-7+ patients had higher capillary dropout in biopsies of skeletal muscle. Aside from these subtle alterations, no significant differences between ASyS subgroups were observed. Interestingly, a tissue-specific subpopulation of CD138+ plasma cells and CXCL12+/CXCL13+CD20+ B cells common to ASyS myositis were identified. These cells were localized in the endomysium associated with alkaline phosphatase+ activated mesenchymal fibroblasts and CD68+MHC-II+CD169+ macrophages. An MHC-I+ and MHC-II+ MxA negative type II interferon-driven milieu of myofiber activation, topographically restricted to the perifascicular area and the adjacent perimysium, as well as perimysial clusters of T follicular helper cells defined an extra-medullary immunological niche for plasma cells and activated B cells. Consistent with this, proteomic analyses of muscle tissues from ASyS patients demonstrated alterations in antigen processing and presentation. In-depth immunological analyses of peripheral blood supported a B-cell/plasma-cell-driven pathology with a shift towards immature B cells, an increase of B-cell-related cytokines and chemokines, and activation of the complement system. We hypothesize that a B-cell-driven pathology with the presence and persistence of a specific subtype of plasma cells in the skeletal muscle is crucially involved in the self-perpetuating chronicity of ASyS myositis. This work provides the conceptual framework for the application of plasma-cell-targeting therapies in ASyS myositis.


Assuntos
Ligases , Miosite , Autoanticorpos , Humanos , Músculo Esquelético/patologia , Miosite/complicações , Miosite/patologia , Plasmócitos , Proteômica
8.
Eur J Neurol ; 29(6): 1847-1854, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35098616

RESUMO

BACKGROUND AND PURPOSE: A fraction of patients with antibody-mediated autoimmune diseases remain unresponsive to first-/second-line and sometimes even to escalation immunotherapies. Because these patients are still affected by poor outcome and increased mortality, we investigated the safety and efficacy of the plasma cell-depleting anti-CD38 antibody daratumumab in life-threatening, antibody-mediated autoimmune diseases. METHODS: In this retrospective, single-center case series, seven patients with autoantibody-driven neurological autoimmune diseases (autoimmune encephalitis, n = 5; neurofascin antibody-associated chronic inflammatory demyelinating polyneuropathy associated with sporadic late onset nemaline myopathy, n = 1; seronegative myasthenia gravis, n = 1) unresponsive to a median of four (range = 4-9) immunotherapies were treated with four to 20 cycles of 16 mg/kg daratumumab. RESULTS: Daratumumab allowed a substantial clinical improvement in all patients, as measured by modified Rankin Scale (mRS; before treatment: mRS =5, n = 7; after treatment: median mRS =4, range = 0-5), Clinical Assessment Scale in Autoimmune Encephalitis (from median 21 to 3 points, n = 5), Inflammatory Neuropathy Cause and Treatment disability score (from 7 to 0 points, n = 1), and Quantitative Myasthenia Gravis score (from 16 to 8 points, n = 1). Daratumumab induced a substantial reduction of disease-specific autoreactive antibodies, total IgG (serum, 66%, n = 7; cerebrospinal fluid, 58%, n = 5), and vaccine-induced titers for rubella (50%) and tetanus toxoid (74%). Treatment-related toxicities Grade 3 or higher occurred in five patients, including one death. CONCLUSIONS: Our findings suggest that daratumumab provided a clinically relevant depletion of autoreactive long-lived plasma cells, identifying plasma cell-targeted therapies as promising escalation therapy for highly active, otherwise treatment-refractory autoantibody-mediated neurological diseases.


Assuntos
Encefalite , Miastenia Gravis , Doenças do Sistema Nervoso , Neurologia , Anticorpos Monoclonais , Autoanticorpos , Doença de Hashimoto , Humanos , Doenças do Sistema Nervoso/tratamento farmacológico , Estudos Retrospectivos
9.
Microb Cell Fact ; 21(1): 274, 2022 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-36578077

RESUMO

BACKGROUND: Extremolytes enable microbes to withstand even the most extreme conditions in nature. Due to their unique protective properties, the small organic molecules, more and more, become high-value active ingredients for the cosmetics and the pharmaceutical industries. While ectoine, the industrial extremolyte flagship, has been successfully commercialized before, an economically viable route to its highly interesting derivative 5-hydroxyectoine (hydroxyectoine) is not existing. RESULTS: Here, we demonstrate high-level hydroxyectoine production, using metabolically engineered strains of C. glutamicum that express a codon-optimized, heterologous ectD gene, encoding for ectoine hydroxylase, to convert supplemented ectoine in the presence of sucrose as growth substrate into the desired derivative. Fourteen out of sixteen codon-optimized ectD variants from phylogenetically diverse bacterial and archaeal donors enabled hydroxyectoine production, showing the strategy to work almost regardless of the origin of the gene. The genes from Pseudomonas stutzeri (PST) and Mycobacterium smegmatis (MSM) worked best and enabled hydroxyectoine production up to 97% yield. Metabolic analyses revealed high enrichment of the ectoines inside the cells, which, inter alia, reduced the synthesis of other compatible solutes, including proline and trehalose. After further optimization, C. glutamicum Ptuf ectDPST achieved a titre of 74 g L-1 hydroxyectoine at 70% selectivity within 12 h, using a simple batch process. In a two-step procedure, hydroxyectoine production from ectoine, previously synthesized fermentatively with C. glutamicum ectABCopt, was successfully achieved without intermediate purification. CONCLUSIONS: C. glutamicum is a well-known and industrially proven host, allowing the synthesis of commercial products with granted GRAS status, a great benefit for a safe production of hydroxyectoine as active ingredient for cosmetic and pharmaceutical applications. Because ectoine is already available at commercial scale, its use as precursor appears straightforward. In the future, two-step processes might provide hydroxyectoine de novo from sugar.


Assuntos
Diamino Aminoácidos , Corynebacterium glutamicum , Corynebacterium glutamicum/genética , Corynebacterium glutamicum/metabolismo , Bactérias/metabolismo
10.
BMC Neurol ; 22(1): 455, 2022 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-36476357

RESUMO

BACKGROUND AND AIMS: Myasthenia Gravis requires expert treatment from specialized neurologists. In Germany, this treatment is mainly provided by 18 Integrated Myasthenia Centers (iMZ) accredited by the German Myasthenia Gravis Association (DMG). The DMG is a large and well-organized patient organisation that is regarded as a trusted source for disease-specific information. The aim of this study was to analyse the type of requests that each of these institutions receives in order to identify any potential unmet needs regarding the availability of advice for patients and caregivers. This data can then be used in further research to tailor modern digital communication tools to the specific needs of MG patients. METHODS: Counselling requests sent via e-mail to both institutions were extracted for defined examination periods and divided into a period 'before COVID-19 pandemic' (01.07.2019-31.12.2019) and 'during COVID-19 pandemic' (01.07.2020-31.12.2020). Requests were then analysed using four main categories: medical requests, organisational issues, COVID-19 and social legislation inquiries. RESULTS: One thousand seven hundred eleven requests for advice were addressed to DMG and iMZ Charité. Most inquiries directed to the DMG (47%; n = 750) were related to medical issues, most frequently to side effects of medications (n = 325; 20%) and questions about treatment (n = 263; 16%), followed by inquiries regarding organisational issues (26%; n = 412). About half of the inquiries (n = 69; 58%) to the iMZ Charité were related to medical issues and almost one in three inquiries concerned organisational issues (n = 37; 30%). About one in ten inquiries concerned socio-legal matters (iMZ: n = 7; 6% and DMG: n = 177; 11%). During the pandemic, COVID-19 related issues accounted for 8% (n = 6) of inquiries at iMZ, and 16% (n = 253) at DMG. CONCLUSIONS: MG sufferers have a high demand for timely advice. In the current setting, they address their requests to both iMZs and the DMG via e-mail. Our findings confirm that the DMG is highly trusted by patients and caregivers and is used to obtain second opinions. A relevant proportion of requests to the iMZ could be answered more effectively through standardized responses or improved process management. The implementation of modern digital solutions, including telemedicine, for communication between patient and specialist should be evaluated in further research.


Assuntos
COVID-19 , Pandemias , Humanos , Estudos Retrospectivos , Alemanha/epidemiologia
11.
J Med Ethics ; 48(1): 50-55, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-32371594

RESUMO

PURPOSE: Scarce evidence exists regarding end-of-life decision (EOLD) in neurocritically ill patients. We investigated the factors associated with EOLD making, including the group and individual characteristics of involved healthcare professionals, in a multiprofessional neurointensive care unit (NICU) setting. MATERIALS AND METHODS: A prospective, observational pilot study was conducted between 2013 and 2014 in a 10-bed NICU. Factors associated with EOLD in long-term neurocritically ill patients were evaluated using an anonymised survey based on a standardised questionnaire. RESULTS: 8 (25%) physicians and 24 (75%) nurses participated in the study by providing their 'treatment decisions' for 14 patients at several time points. EOLD was 'made' 44 (31%) times, while maintenance of life support 98 (69%) times. EOLD patterns were not significantly different between professional groups. The individual characteristics of the professionals (age, gender, religion, personal experience with death of family member and NICU experience) had no significant impact on decisions to forgo or maintain life-sustaining therapy. EOLD was patient-specific (intraclass correlation coefficient: 0.861), with the presence of acute life-threatening disease (OR (95% CI): 18.199 (1.721 to 192.405), p=0.038) and low expected patient quality of life (OR (95% CI): 9.276 (1.131 to 76.099), p=0.016) being significant and independent determinants for withholding or withdrawing life-sustaining treatment. CONCLUSIONS: Our findings suggest that EOLD in NICU relies mainly on patient prognosis and not on the characteristics of the healthcare professionals.


Assuntos
Qualidade de Vida , Assistência Terminal , Tomada de Decisões , Humanos , Cuidados para Prolongar a Vida , Projetos Piloto , Estudos Prospectivos , Suspensão de Tratamento
12.
Stroke ; 52(1): 325-330, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33280547

RESUMO

BACKGROUND AND PURPOSE: Several clinical scoring systems as well as biomarkers have been proposed to predict stroke-associated pneumonia (SAP). We aimed to externally and competitively validate SAP scores and hypothesized that 5 selected biomarkers would improve performance of these scores. METHODS: We pooled the clinical data of 2 acute stroke studies with identical data assessment: STRAWINSKI and PREDICT. Biomarkers (ultrasensitive procalcitonin; mid-regional proadrenomedullin; mid-regional proatrionatriuretic peptide; ultrasensitive copeptin; C-terminal proendothelin) were measured from hospital admission serum samples. A literature search was performed to identify SAP prediction scores. We then calculated multivariate regression models with the individual scores and the biomarkers. Areas under receiver operating characteristic curves were used to compare discrimination of these scores and models. RESULTS: The combined cohort consisted of 683 cases, of which 573 had available backup samples to perform the biomarker analysis. Literature search identified 9 SAP prediction scores. Our data set enabled us to calculate 5 of these scores. The scores had area under receiver operating characteristic curve of 0.543 to 0.651 for physician determined SAP, 0.574 to 0.685 for probable and 0.689 to 0.811 for definite SAP according to Pneumonia in Stroke Consensus group criteria. Multivariate models of the scores with biomarkers improved virtually all predictions, but mostly in the range of an area under receiver operating characteristic curve delta of 0.05. CONCLUSIONS: All SAP prediction scores identified patients who would develop SAP with fair to strong capabilities, with better discrimination when stricter criteria for SAP diagnosis were applied. The selected biomarkers provided only limited added predictive value, currently not warranting addition of these markers to prediction models. Registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT01264549 and NCT01079728.


Assuntos
Biomarcadores/sangue , Pneumonia/sangue , Pneumonia/etiologia , Acidente Vascular Cerebral/complicações , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Valor Preditivo dos Testes , Prognóstico , Curva ROC , Medição de Risco
13.
Proc Biol Sci ; 288(1955): 20211359, 2021 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-34284626

RESUMO

Looking to nature for inspiration has led to many diverse technological advances. The spiral valve intestine of sharks has provided the opportunity to observe the efficiency of different valve systems. It is supposed that the spiral intestine present in sharks, skates and rays slows the transit rate of digesta through the gut and provides increased surface area for the absorption of nutrients. In this investigation, we use a novel technique-creating three-dimensional reconstructions from CT scans of spiral intestines-to describe the morphology of the spiral intestine of at least one species from 22 different shark families. We discuss the morphological data in an evolutionary, dietary and functional context. The evolutionary analyses suggest that the columnar morphology is the ancestral form of the spiral intestine. Dietary analyses reveal no correlation between diet type and spiral intestine morphology. Flow rate was slowed significantly more when the two funnel-shaped spiral intestines were subjected to flow in the posterior to anterior direction, indicating their success at producing unidirectional flow, similar to a Tesla valve. These data are available to generate additional three-dimensional morphometrics, create computational models of the intestine, as well as to further explore the function of the gastrointestinal tract of sharks in structural and physiological contexts.


Assuntos
Tubarões , Rajidae , Animais , Evolução Biológica , Trato Gastrointestinal , Humanos , Intestinos
14.
Metab Eng ; 67: 293-307, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34314893

RESUMO

Seaweeds emerge as promising third-generation renewable for sustainable bioproduction. In the present work, we valorized brown seaweed to produce l-lysine, the world's leading feed amino acid, using Corynebacterium glutamicum, which was streamlined by systems metabolic engineering. The mutant C. glutamicum SEA-1 served as a starting point for development because it produced small amounts of l-lysine from mannitol, a major seaweed sugar, because of the deletion of its arabitol repressor AtlR and its engineered l-lysine pathway. Starting from SEA-1, we systematically optimized the microbe to redirect excess NADH, formed on the sugar alcohol, towards NADPH, required for l-lysine synthesis. The mannitol dehydrogenase variant MtlD D75A, inspired by 3D protein homology modelling, partly generated NADPH during the oxidation of mannitol to fructose, leading to a 70% increased l-lysine yield in strain SEA-2C. Several rounds of strain engineering further increased NADPH supply and l-lysine production. The best strain, SEA-7, overexpressed the membrane-bound transhydrogenase pntAB together with codon-optimized gapN, encoding NADPH-dependent glyceraldehyde 3-phosphate dehydrogenase, and mak, encoding fructokinase. In a fed-batch process, SEA-7 produced 76 g L-1l-lysine from mannitol at a yield of 0.26 mol mol-1 and a maximum productivity of 2.1 g L-1 h-1. Finally, SEA-7 was integrated into seaweed valorization cascades. Aqua-cultured Laminaria digitata, a major seaweed for commercial alginate, was extracted and hydrolyzed enzymatically, followed by recovery and clean-up of pure alginate gum. The residual sugar-based mixture was converted to l-lysine at a yield of 0.27 C-mol C-mol-1 using SEA-7. Second, stems of the wild-harvested seaweed Durvillaea antarctica, obtained as waste during commercial processing of the blades for human consumption, were extracted using acid treatment. Fermentation of the hydrolysate using SEA-7 provided l-lysine at a yield of 0.40 C-mol C-mol-1. Our findings enable improvement of the efficiency of seaweed biorefineries using tailor-made C. glutamicum strains.


Assuntos
Corynebacterium glutamicum , Alga Marinha , Corynebacterium glutamicum/genética , Humanos , Lisina/genética , Engenharia Metabólica , NADP
15.
J Emerg Nurs ; 47(1): 28-32, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33183770

RESUMO

Hydrofluoric acid is a caustic compound found in a wide variety of items for household and industrial uses. Dermal exposures can be visually unimpressive on presentation but still have fatal complications. This case review includes a description of a patient presenting with a dermal hydrofluoric acid burn that was effectively treated with topical calcium gluconate gel. Also highlighted are the challenges faced with recognizing the severity and appropriately treating dermal hydrofluoric acid burns in the emergency department.


Assuntos
Queimaduras Químicas/tratamento farmacológico , Queimaduras Químicas/etiologia , Gluconato de Cálcio/administração & dosagem , Traumatismos da Mão/induzido quimicamente , Traumatismos da Mão/tratamento farmacológico , Ácido Fluorídrico/toxicidade , Administração Tópica , Adulto , Serviço Hospitalar de Emergência , Géis , Humanos , Masculino
16.
BMC Neurol ; 19(1): 118, 2019 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-31176377

RESUMO

BACKGROUND: In patients suffering from Chronic Inflammatory Demyelinating Polyneuropathy (CIDP) disease severity is assessed by Medical Research Counsil (MRC) Scale or Inflammatory Neuropathy Cause and Treatment (INCAT) disability score. However, none of these methods is appropriate to objectively assess muscle weakness or to detect very small subclinical changes. More objective and quantitative measures are needed in order to evaluate treatment efficiency or to detect subclinical affection of upper limps for early diagnosis. The goal of our study was to objectively quantify muscular weakness in CIDP patients with the non-invasive Quantitative Motor (Q-Motor) test of Grip Force Assessment (QGFA) as well as the Involuntary Movement Assessment (QIMA) and to search for differences between typical and atypical CIDP variants. In addition, we hypothesized that Q-Motor findings correlate with disease severity scales such as MRC or INCAT score. METHODS: In this cross-sectional exploratory proof-of-concept study subjects with confirmed diagnosis of typical or atypical CIDP were examined and compared to healthy controls (HC). For Q-Motor tests all subjects had to lift a device (250 g and 500 g) equipped with an electromagnetic sensor that measured grip force (GF) and three-dimensional changes in position and orientation. The measures "grip force variability" (GFV), "position index" (PI) and "orientation index" (OI) were provided to assess involuntary movements due to muscular weakness. RESULTS: 33 patients with CIDP and 28 HC were included. All measures were significantly elevated in CIDP patients for both devices in the right and left hand compared to healthy controls. Subgroup analysis revealed no differences between typical and atypical CIDP variants. INCAT score only weakly correlated with OI and PI. However, there was a stronger correlation between MRC and QIMA parameters in both hands. CONCLUSION: Q-Motor assessments were capable to objectively assess muscular weakness in CIDP. In particular, QIMA measures detected subclinical generalized muscle weakness even in patients with milder disability. Sensitivity and rater-independence of Q-Motor assessments support a further exploration of QIMA measures as potential endpoints for future clinical trials in CIDP.


Assuntos
Força da Mão/fisiologia , Debilidade Muscular , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Debilidade Muscular/diagnóstico , Debilidade Muscular/etiologia , Debilidade Muscular/fisiopatologia , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica/complicações , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica/fisiopatologia , Estudo de Prova de Conceito
18.
Metab Eng ; 47: 475-487, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29709649

RESUMO

The amino acid lysine is among the world's most important biotechnological products, and enabling its manufacture from the most attractive new materials is an ever-present challenge. In this study, we describe a cell factory of Corynebacterium glutamicum, which produces lysine from mannitol. A preliminary mutant C. glutamicum SEA-1 obtained by the deletion of the mannitol repressor MtlR in the glucose-based, lysine-producing strain C. glutamicum LYS-12 produced only small amounts of lysine. This limitation was due to a significant accumulation of fructose and a limited NADPH supply, which caused a low flux of only 6% into the oxidative pentose phosphate (PP) pathway. Subsequent expression of fructokinase slightly increased production but failed to substantially redirect the flux from the Emden-Meyerhof-Parnas (EMP) pathway to the PP pathway. This suggested the design of C. glutamicum SEA-3, which overexpressed the NADP-dependent glyceraldehyde 3-phosphate dehydrogenase GapN from Streptococcus mutans and coupled the EMP pathway flux to NADPH formation. When grown on mannitol, the SEA-3 strain had a lysine yield of 0.24 mol mol-1 and a specific productivity of 1.3 mmol g-1 h-1, approximately 60% and 75% higher, respectively, than those of the basic producer SEA-1. A computational pathway analysis revealed that this design would potentially enable a lysine yield of 0.9 mol mol-1, providing room for further development. Our findings open new avenues for lysine production from marine macroalgae, which is farmed globally as an attractive third-generation renewable resource. Mannitol is a major constituent of these algae (up to 30% and higher) and can be easily extracted from their biomass with hot water.


Assuntos
Corynebacterium glutamicum , Lisina , Manitol/metabolismo , Engenharia Metabólica , Microrganismos Geneticamente Modificados , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Corynebacterium glutamicum/genética , Corynebacterium glutamicum/metabolismo , Lisina/biossíntese , Lisina/genética , Microrganismos Geneticamente Modificados/genética , Microrganismos Geneticamente Modificados/metabolismo , Streptococcus mutans/genética
19.
Clin Immunol ; 179: 40-46, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28286113

RESUMO

Although myasthenia gravis (MG) is a classic autoantibody-mediated disease, T cells are centrally involved in its pathogenesis. In recent years a number of studies have analyzed the role of CD4+ FoxP3+ regulatory T cells (Treg) in the disease with contradictory results. Here, the generation of Treg was significantly reduced in thymoma as compared to thymic hyperplasia and normal thymus tissue (p=0.0002). In the peripheral blood, Treg subsets classified according to CD49d, HELIOS and CD45RA expression changed after thymectomy and in the long-term course of immunosuppression. Compared to healthy volunteers the frequency of CD45RA+FoxP3low Treg was reduced in MG patients in general (p=0.037) and in particular in patients without immunosuppression (p=0.036). In our study, thymectomy and immunosuppressive treatment were associated with changes in Treg subpopulations. The reduced frequency of CD45RA+FoxP3low Treg we observed in MG patients might play a role in MG pathogenesis.


Assuntos
Miastenia Gravis/imunologia , Subpopulações de Linfócitos T/imunologia , Linfócitos T Reguladores/imunologia , Feminino , Humanos , Imunossupressores/uso terapêutico , Masculino , Pessoa de Meia-Idade , Miastenia Gravis/tratamento farmacológico , Miastenia Gravis/cirurgia , Subpopulações de Linfócitos T/efeitos dos fármacos , Linfócitos T Reguladores/efeitos dos fármacos , Timectomia , Timoma/tratamento farmacológico , Timoma/imunologia , Timoma/cirurgia , Timo/patologia , Hiperplasia do Timo/tratamento farmacológico , Hiperplasia do Timo/imunologia , Hiperplasia do Timo/cirurgia , Neoplasias do Timo/tratamento farmacológico , Neoplasias do Timo/imunologia , Neoplasias do Timo/cirurgia
20.
J Exp Biol ; 220(Pt 18): 3336-3343, 2017 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-28705829

RESUMO

Hammerhead sharks (Sphyrnidae) exhibit a large amount of morphological variation within the family, making them the focus of many studies. The size of the laterally expanded head, or cephalofoil, is inversely correlated with pectoral fin area. The inverse relationship between cephalofoil and pectoral fin size in this family suggests that they might serve a complementary role in lift generation. The cephalofoil is also hypothesized to increase olfaction, electroreception and vision; however, little is known about how morphological variation impacts post-cranial swimming kinematics. Previous studies demonstrate that the bonnethead and scalloped hammerhead have significantly different yaw amplitude, and we hypothesized that these species utilize varied frequency and amplitude of undulation along the body. We analyzed video of free-swimming sharks to examine kinematics and 2D morphological variables of the bonnethead and scalloped hammerhead. We also examined the second moment of area along the length of the body and over a size range of animals to determine whether there were shape differences along the body of these species and whether those changed over ontogeny. We found that both species swim with the same standardized velocity and Strouhal number, but there was no correlation between two-dimensional morphology and swimming kinematics. However, the bonnethead has a dorso-ventrally compressed anterior trunk and undulates with greater amplitude, whereas the scalloped hammerhead has a laterally compressed anterior trunk and undulates with lower amplitude. We propose that differences in cross-sectional trunk morphology account for interspecific differences in undulatory amplitude. We also found that for both species, undulatory frequency is significantly greater in the anterior body compared with all other body regions. We hypothesize that the bonnethead and scalloped hammerhead swim with a double oscillation system.


Assuntos
Tubarões/anatomia & histologia , Tubarões/fisiologia , Especificidade da Espécie , Natação , Animais , Fenômenos Biomecânicos
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