RESUMO
Aerogels are becoming a promising platform to fabricate photothermal materials for use in solar steam generation (SSG), which have remarkable application potential in solar desalination, due to their excellent thermal management, salt resistance, and considerable water evaporation rate. In this work, a novel photothermal material is fabricated by forming a suspension between sugarcane bagasse fibers (SBF) and poly(vinyl alcohol), tannic acid (TA), and Fe3+ solutions via hydrogen bonds of hydroxyl groups. After freeze drying, the fabricated SBF aerogel-based photothermal (SBFAP) material possesses a 3D interconnected porous microstructure, which could enhance water transportation ability, reduce thermal conductivity, and quickly dissolve salt crystals on the SBFAP surface. Thanks to the formation of micro/nanosized complexes between TA and Fe3+ ions on the SBFAP material, the SBFAP exhibits high light capture and water evaporation rate (2.28 kg m-2 h-1). In particular, due to strong hydrogen bonding and the SBF, the SBFAP material is reinforced, thereby exhibiting excellent structural stability in seawater. Moreover, the high salt tolerance of SBFAP favors its high desalination performance for at least 76 days of continuous evaporation under actual conditions. This research paves the way for the fabrication of natural cellulose fiber-based photothermal materials for application in solar desalination.
RESUMO
Some research indicates that soil seed banks can promote species coexistence through storage effects. However, the seed bank mechanism that maintains plant assembly and its role in degraded grassland restoration are still not clear. We collected seed bank samples from early, mid and late secondary successional stages of an abandoned subalpine meadow on the Tibetan Plateau, and samples from each stage were exposed to full (i.e., natural), mid, and low light treatments in the field to represent light availability at the bottom/understory (soil surface) of a plant community in the early, mid and late stages of succession, respectively. Species richness, seed density, species composition, and community weighted mean values (CWMs) of seed mass of the species whose seeds germinated in soil samples were evaluated. In response to the light treatments, species richness increased significantly with increased light only for the late successional stage, seed density increased significantly with increased light only in the early and mid successional stages, and seed mass decreased significantly with increased light only in the mid and late successional stages. Species composition differed significantly among the light treatments only in the late successional stage. For the successional series, species richness and seed mass of the species that germinated increased significantly with succession only under mid and full light treatments. Seed density decreased significantly with succession in each light treatment. Species composition differed significantly between the early- and late stage and between the mid and late stage in each light treatment. Both the abiotic (light) and biotic (seed mass) factors influence seed bank recruitment to the plant community. Regeneration of small-seeded species in the seed bank was inhibited under low light in the late successional stage. The balance of stochastic and deterministic processes along a successional gradient was determined by regeneration from the seed bank depending on light intensity change. Differences in seed response to light intensity change largely determined plant community assembly. Our findings should help in the development of effective conservation and restoration strategies.
Assuntos
Ecossistema , Pradaria , Banco de Sementes , Plantas , Sementes , SoloRESUMO
BACKGROUND: Parental exposure to rare earth elements (REEs) could increase the risk of premature rupture of membranes, a major cause of spontaneous preterm birth (SPB). In addition, different subtypes of SPB, such as spontaneous preterm labor (SPL) and preterm premature rupture of membranes (PPROM), may have different susceptibility to environmental exposure. Therefore, we investigated the potential associations between REE exposure in different trimesters and SPB and its subtypes. METHODS: A nested case-control study was performed. We included 244 women with SPB as cases and 244 women with full-term delivery as controls. The plasma concentrations of light REEs were measured in the first and third trimesters. Logistic regression was used to analyze the associations between single REE levels and SPB, and Bayesian kernel machine regression (BKMR) was used to analyze the mixed-exposure effect. RESULTS: Exposure to light REEs was associated with SPB and its subtypes only in the third trimester. Specifically, the intermediate- and highest-tertile concentration groups of La and the highest-tertile concentration group of Sm were associated with an increased risk of SPL, with adjusted odds ratios (AORs) of 2.00 (95% CIs: 1.07-3.75), 1.87 (95% CIs: 1.01-3.44), and 1.82 (95% CIs: 1.00-3.30), respectively. The highest-tertile concentration group of Pr was associated with an increased risk of PPROM, with an AOR of 1.69 (95% CIs: 1.00-2.85). Similar results were also found in BKMR models. CONCLUSIONS: La and Sm levels in plasma may be associated with the risk of SPL, and Pr levels in plasma may be associated with the risk of PPROM.
Assuntos
Nascimento Prematuro , Recém-Nascido , Feminino , Humanos , Nascimento Prematuro/epidemiologia , Estudos de Casos e Controles , Estudos de Coortes , Pequim/epidemiologia , Teorema de BayesRESUMO
A comprehensive understanding of surface reconstruction was critical to developing high performance lattice oxygen oxidation mechanism (LOM) based perovskite electrocatalysts. Traditionally, the primary determining factor of the surface reconstruction process was believed to be the oxygen vacancy formation energy. Hence, most previous studies focused on optimizing composition to reduce the oxygen vacancy formation energy, which in turn facilitated the surface reconstruction process. Here, for the first time, we found that adding oxyanions (SO4 2- , CO3 2- , NO3 - ) into the electrolyte could effectively regulate the solid-liquid interface, significantly accelerating the surface reconstruction process and enhancing oxygen evolution reaction (OER) activities. Further studies indicated that the added oxyanions would adsorb onto the solid-liquid interface layer, disrupting the dynamic equilibrium between the adsorbed OH- ions and the OH- ions generated during surface reconstruction process. As such, the OH- ions generated during surface reconstruction process could be more readily released into the electrolyte, thereby leading to an acceleration of the surface reconstruction. Thus, it was expected that our finding would provide a new layer of understanding to the surface reconstruction process in LOM-based perovskite electrocatalysts.
RESUMO
Cardiac paragangliomas are exceedingly rare. Herein, we describe a patient with a large dopaminesecreting cardiac paraganglioma who had a history of pheochromocytoma after right adrenalectomy. The cardiac surgery was uneventful and without blood pressure fluctuations.The measurement of plasma-free metanephrines or urinary fractionated metanephrines is used as an initial screening test for pheochromocytoma or paraganglioma detection. However, these results must be combined with those of a plasma 3-methoxytyramine test to accurately establish the rare dopaminergic phenotype of pheochromocytomas or paragangliomas, if suspected. F-FDOPA (6-[18F]-L-fluoro-L-3, 4-dihydroxyphenylalanine)-based positron emission tomography (PET) and PET-computed tomography are relatively sensitive and specific; therefore, these techniques are recommended for patients with pheochromocytomas or paragangliomas before operation or during postoperative follow-up.
Assuntos
Neoplasias das Glândulas Suprarrenais , Paraganglioma , Feocromocitoma , Neoplasias das Glândulas Suprarrenais/genética , Neoplasias das Glândulas Suprarrenais/cirurgia , Adrenalectomia , Dopamina , Humanos , Paraganglioma/diagnóstico , Paraganglioma/cirurgia , Feocromocitoma/diagnóstico , Feocromocitoma/genética , Feocromocitoma/cirurgia , Base do CrânioRESUMO
BACKGROUND: Immunoglobulin M (IgM) mesangial deposition in pediatric minimal change disease (MCD) has been reported to be associated with steroid dependence and poor renal outcomes. However, the evidence linking the impacts of IgM mesangial deposition to the treatment prognosis in adult-onset MCD is still elusive. METHODS: In this retrospective cohort study, 37 adult patients with MCD received kidney biopsies from January 2010 to May 2020. Immunofluorescence microscopy was performed and the patients dichotomized according to IgM mesangial deposition (12 patients with positive IgM deposition; 25 patients with negative IgM deposition). We analyzed the clinical features, the dosage of immunosuppressive agents, and the response to treatment for 2 years between the two groups. RESULTS: Analysis of the clinical symptoms, the dosage of immunosuppressive treatment, and the time to remission revealed no statistical difference between the groups. However, compared to the negative IgM group, the frequency of relapses was significantly higher in the positive IgM group during the two-year follow-up period (the negative IgM group 0.25 episodes/year; the positive IgM group 0.75 episodes/year, p = 0.029). Furthermore, multivariate linear regression revealed that the positivity of IgM mesangial deposition is independently associated with the frequency of relapses (regression coefficient B 0.450, 95% CI 0.116-0.784, p = 0.010). CONCLUSIONS: Our findings indicated that adult-onset MCD patients with IgM mesangial deposition have a high risk of relapses. Therefore, intensive monitoring of disease activity should be considered in MCD adults with IgM mesangial deposition.
Assuntos
Mesângio Glomerular/metabolismo , Imunoglobulina M/metabolismo , Nefrose Lipoide/etiologia , Adulto , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos , Fatores de Risco , Adulto JovemRESUMO
The relationship between maternal mercury (Hg) intake and the risk of spontaneous preterm birth (SPB) remains unclear. We conducted a nested case-control study from a prospective cohort in Shanxi Province, China, to explore their associations. In total, 126 pregnant women with SPB (cases) and 348 controls with term delivery were included. We measured the Hg concentrations in their serum (Hgs) and blood cell (Hgc) fractions and calculated the concentration ratio of Hg in serum to Hg in blood cells (Hgs/c). We found that only the Hgs/c in the case group was slightly higher than that in control group. The OR of Hgs/c associated with SPB risk was 1.57 [95%CI: 0.99-2.46] with adjusting confounders. After stratification by sampling time, the association above was only statistically significant in the first trimester. High Hgs/c may increase the risk of SPB in the first trimester among women with relatively low Hg exposure.
Assuntos
Poluentes Ambientais/sangue , Exposição Materna/estatística & dados numéricos , Mercúrio/sangue , Nascimento Prematuro/sangue , Adulto , Células Sanguíneas , Estudos de Casos e Controles , China/epidemiologia , Estudos de Coortes , Feminino , Humanos , Recém-Nascido , Gravidez , Nascimento Prematuro/epidemiologia , Estudos ProspectivosRESUMO
Titanium (Ti) is commonly used in additives in the form of titanium dioxide (TiO2). However, our understanding of the effect of Ti on reproductive health remains limited. This nested case-control study, performed in a Ti mining exposure field, investigated the association between maternal blood Ti concentration and the risk of low birth weight (LBW), as well as the potential biological mechanism. A total of 45 women who delivered LBW infants (cases) and 352 women with normal birth weight infants (controls) were included. We collected maternal peripheral blood samples in the first or early second trimester to measure Ti concentration in serum (Tisr) and blood cells (Tibc), as well as inflammatory, lipid, and oxidative stress biomarkers thereof. The demographic characteristics of the women included in the study were also obtained. The results showed that the median total blood Ti concentration (Titb) in the case group was significantly higher than that in the control group (134 vs. 129 ng/mL, P = 0.039). A higher Titb level was associated with a greater risk of LBW [odds ratio = 2.62; 95% confidence interval (CI): 1.16-5.90], but no such association was observed for Tisr or Tibc after adjusting for potential confounders. The serum lipid biomarkers TC, TG, and total lipids (TL) were all negatively associated with Tisr and Titb. Serum 8-OHdG was positively associated with Tibc. We concluded that a high Titb during early pregnancy may increase the risk of LBW. Lipid metabolism and oxidative stress may play an important role in the adverse health effects associated with Ti exposure. Thus, our results merit more attention to the probable adverse effects of titanium exposure during pregnancy.
Assuntos
Recém-Nascido de Baixo Peso , Exposição Materna/efeitos adversos , Saúde Reprodutiva , Titânio/toxicidade , Adulto , Estudos de Casos e Controles , China , Feminino , Humanos , Recém-Nascido , Metabolismo dos Lipídeos/efeitos dos fármacos , Razão de Chances , Estresse Oxidativo/efeitos dos fármacos , Gravidez , Titânio/sangueRESUMO
The Tibetan Plateau has undergone significant climate warming in recent decades, and precipitation has also become increasingly variable. Much research has explored the effects of climate change on vegetation on this plateau. As potential vegetation buried in the soil, the soil seed bank is an important resource for ecosystem restoration and resilience. However, almost no studies have explored the effects of climate change on seed banks and the mechanisms of these effects. We used an altitudinal gradient to represent a decrease in temperature and collected soil seed bank samples from 27 alpine meadows (3,158-4,002 m) along this gradient. A structural equation model was used to explore the direct effects of mean annual precipitation (MAP) and mean annual temperature (MAT) on the soil seed bank and their indirect effects through aboveground vegetation and soil environmental factors. The species richness and abundance of the aboveground vegetation varied little along the altitudinal gradient, while the species richness and density of the seed bank decreased. The similarity between the seed bank and aboveground vegetation decreased with altitude; specifically, it decreased with MAP but was not related to MAT. The increase in MAP with increasing altitude directly decreased the species richness and density of the seed bank, while the increase in MAP and decrease in MAT with increasing altitude indirectly increased and decreased the species richness of the seed bank, respectively, by directly increasing and decreasing the species richness of the plant community. The size of the soil seed bank declined with increasing altitude. Increases in precipitation directly decreased the species richness and density and indirectly decreased the species richness of the seed bank with increasing elevation. The role of the seed bank in aboveground plant community regeneration decreases with increasing altitude, and this process is controlled by precipitation but not temperature.
Assuntos
Altitude , Ecossistema , Pradaria , Banco de Sementes , SoloRESUMO
BACKGROUND: Diabetic nephropathy (DN) is the most prevalent cause of renal disease in type 2 diabetic patients and is usually diagnosed clinically. A kidney biopsy is considered when non-diabetic renal disease (NDRD) is suspected, such as rapid progression in renal function impairment and severe proteinuria. Still, there is yet no consensus on the timing of kidney biopsy in type 2 diabetic patients. This study aims to identify markers that can help differentiate between DN and NDRD and guide the decision of kidney biopsy. METHODS: We retrospectively reviewed patients with type 2 diabetes who received kidney biopsy from 2008 to 2017 at Taipei Veterans General Hospital. Ophthalmologist consultation and outpatient records, diagnosis of kidney biopsy, laboratory data, and clinical characteristics were collected. RESULTS: This study enrolled 160 type 2 diabetic patients, among which 120 (75%) had isolated DN and 40 (25%) had NDRD ± DN (26 had isolated NDRD, and 14 had NDRD superimposed on DN). In multivariate logistic regression analysis, DM duration (odds ratio [OR]: 0.907; 95% confidence interval [CI]: 0.842-0.977; P = 0.01), diabetic retinopathy (OR: 0.196; 95% CI: 0.061-0.627; P = 0.006), and urinary RBC (OR: 1.068; 95% CI: 1.024-1.115; P = 0.002) were independent predictors of NDRD. In patients with diabetic retinopathy (n = 112, 70%), the presence of proliferative diabetic retinopathy, pan-retinal photocoagulation, and hematuria were factors predicting NDRD; and in patients without diabetic retinopathy (n = 48, 30%), short DM duration and hematuria were factors predicting NDRD. CONCLUSIONS: Using diabetic retinopathy, DM duration, and hematuria, we developed a 3-step approach to stratify patients into three categories with the different likelihoods of having NDRD. Then different strategies could be taken accordingly. Our stepwise approach is easy to follow and may serve as an appropriate and useful tool to help clinicians in making decisions of kidney biopsy in type 2 DM patients presenting with kidney diseases.
Assuntos
Biópsia , Diabetes Mellitus Tipo 2/complicações , Nefropatias Diabéticas/patologia , Hematúria , Rim/patologia , Biópsia/métodos , Biópsia/normas , Tomada de Decisão Clínica/métodos , Diabetes Mellitus Tipo 2/epidemiologia , Nefropatias Diabéticas/fisiopatologia , Retinopatia Diabética/diagnóstico por imagem , Diagnóstico Diferencial , Progressão da Doença , Feminino , Hematúria/diagnóstico , Hematúria/etiologia , Humanos , Testes de Função Renal/métodos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Taiwan/epidemiologia , Tempo para o TratamentoRESUMO
PURPOSE: Evaluation standards and treatment initiation timing have been debated for a long time, particularly for late-onset Fabry disease (FD), because of its slow progression. However, early initiation of enzyme replacement therapy (ERT) for FD could be effective in stabilizing the disease progression and potentially preventing irreversible organ damage. We aimed to examine globotriaosylceramide (Gb3) deposits in patients' endomyocardial biopsies to understand the early pathogenesis of FD cardiomyopathy. METHODS: Immunofluorescent (IF) staining of Gb3 and lysosomal-associated membrane protein 1 (LAMP-1) was performed on endomyocardial biopsies of patients suspected of Fabry cardiomyopathy who had negative or only slight Gb3 accumulation determined by toluidine blue staining and electron microscopic examination. RESULTS: The IF staining results revealed that all patients examined had abundant Gb3 accumulation in their cardiomyocytes, including the ones who are negative for inclusion bodies. Furthermore, we found that early Gb3 deposits were mostly confined within lysosomes, while they appeared extralysosomally at a later stage. CONCLUSION: A significant amount of lysosomal Gb3 deposits could be detected by IF staining in cardiac tissue before the formation of inclusion bodies, suggesting the cardiomyocytes might have been experiencing cellular stress and damage early on, before the appearance of typical pathological changes of FD during the disease progression.
Assuntos
Doença de Fabry/diagnóstico , Globosídeos/metabolismo , Lisossomos/metabolismo , Miocárdio/metabolismo , Triexosilceramidas/metabolismo , Adulto , Biópsia , Progressão da Doença , Terapia de Reposição de Enzimas , Doença de Fabry/diagnóstico por imagem , Doença de Fabry/metabolismo , Doença de Fabry/patologia , Imunofluorescência , Globosídeos/genética , Humanos , Proteínas de Membrana Lisossomal/genética , Lisossomos/patologia , Masculino , Pessoa de Meia-Idade , Miocárdio/patologia , Triexosilceramidas/genéticaRESUMO
Given advancements in cancer immunity, cancer treatment has gained breakthrough developments. Immune checkpoint inhibitors, such as programmed cell death 1 (PD-1) inhibitors, are the most promising drugs in the field and have been approved to treat various types of cancer, such as metastatic melanoma, head and neck squamous cell carcinoma, and urothelial carcinoma. However, whether PD-1 inhibitors should be administered to renal transplant patients with advanced cancer remains unclear because the T-cells produced after administration of these inhibitors act against not only tumor antigens but also donor alloantigens. Thus, the use of PD-1 inhibitors in kidney-transplanted patients with advanced cancer is limited on account of the high risk of graft failure due to acute rejection. Hence, finding optimal treatment regimens to enhance the tumor-specific T-cell response and decrease T-cell-mediated alloreactivity after administration of a PD-1 inhibitor is necessary. Thus far, no recommendations for the use of PD-1 inhibitors to treat cancer in renal transplant patients are yet available, and very few cases reporting kidney-transplanted patients treated with PD-1 inhibitors are available in the literature. Therefore, in this work, we review the published cases and suggest feasible approaches for renal transplant patients with advanced malignancy treated by a PD-1 inhibitor. Of the 22 cases we obtained, four patients maintained intact grafts without tumor progression after treatment with a PD-1 inhibitor. Among these patients, one maintained steroid dose before initiation of anti-PD1, two received immunosuppressive regimens with low-dose steroid and calcineurin inhibitor (CNI)-elimination with sirolimus before initiation of anti-PD-1 therapy, and one received combined anti-PD-1, anti-vascular endothelial growth factor (VEGF), and chemotherapy with unchanged immunosuppressive regimens. mammalian target of rapamycin (mTOR) inhibitors and anti-VEGF may act as regulators of tumor-specific and allogenic T-cells. However, more studies are necessary to explore the optimal therapy and ensure the safety and efficacy of PD-1 inhibitors in kidney-transplanted patients.
Assuntos
Antineoplásicos Imunológicos/uso terapêutico , Transplante de Rim , Neoplasias/tratamento farmacológico , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Animais , Antineoplásicos Imunológicos/farmacologia , Rejeição de Enxerto/imunologia , Humanos , Imunossupressores/farmacologia , Imunossupressores/uso terapêutico , Estadiamento de Neoplasias , Neoplasias/imunologia , Neoplasias/metabolismo , Neoplasias/patologia , Resultado do TratamentoRESUMO
BACKGROUND: Tbx5 deficiency in zebrafish causes several abnormal phenotypes of the heart and pectoral fins. It has been reported that exogenous human growth hormone can enhance expression of downstream mediators in the growth hormone and insulin-like growth factor I (IGF-I) pathway and partially restore dysmorphogenesis in tbx5 morphants. This study aimed to further evaluate the effects of IGF-I on cell apoptosis and dysmorphogenesis in zebrafish embryos deficient for tbx5. RESULTS: Among the five studied groups of zebrafish embryos (wild-type embryos [WT], tbx5 morphants [MO], mismatched tbx5 morpholino-treated wild-type embryos [MIS], IGF-I-treated wild-type embryos [WTIGF1], and IGF-I-treated tbx5 morphants [MOIGF1]), the expression levels of the ifg1, igf1-ra, ifg-rb, erk1, and akt2 genes as well as the ERK and AKT proteins were significantly reduced in the MO group, but were partially restored in the MOIGF1 group. These expression levels remained normal in the WT, MIS, and WTIGF1 groups. Exogenous human IGF-I also reduced the incidence of phenotypic anomalies, decreased the expression levels of apoptotic genes and proteins, suppressed cell apoptosis, and improved survival of the MOIGF1 group. CONCLUSIONS: These results suggest that IGF-I has an anti-apoptotic protective effect in zebrafish embryos with tbx5 deficiency.
Assuntos
Apoptose , Embrião não Mamífero/metabolismo , Fator de Crescimento Insulin-Like I/farmacologia , Morfogênese , Proteínas com Domínio T/deficiência , Peixe-Zebra/embriologia , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Embrião não Mamífero/efeitos dos fármacos , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Humanos , Morfogênese/efeitos dos fármacos , Morfogênese/genética , Morfolinos/farmacologia , Miocárdio/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Fenótipo , Fosforilação/efeitos dos fármacos , Análise de Sobrevida , Proteínas com Domínio T/metabolismo , Peixe-Zebra/genéticaRESUMO
AIMS: To investigate the pathogenic role of activation of the mammalian target of the rapamycin (mTOR) in the ketamine induced microvascular injury. METHODS: Twenty-three patients with ketamine-induced cystitis (KC) and 16 control volunteers were recruited. Bladder tissues were obtained from both groups by cystoscopic biopsies. Phospho-S6 ribosomal protein (p-S6RP), an end product of the mTOR pathway, was stained in the urinary bladder from both groups. Endothelial cells of the urinary bladder (HBdMECs) were examined to investigate the in vitro activation of the mTOR pathway and the co-expression of the endothelial marker (cluster of differentiation 31 [CD31]) and the mesenchymal marker (fibroblast-specific protein 1 [FSP-1]). RESULTS: Expression of p-S6RP increased significantly after ketamine exposure, especially in the vesical microvessels of KC patients. In HBdMECs treated with 100 µM Ketamine, time-dependent activation of the mTOR pathway occurred, with significantly increased levels of the phosphorylated forms of mTOR at 30 min and of S6RP and p70S6 kinase (p70S6K) at 6 h. The increased level of p-S6RP returned to baseline within 2 days after ketamine exposure. The co-expression of CD31 and FSP-1 implied that EndMT was present in HBdMECs at 7 days after ketamine treatment, while TGF-ß1 facilitated significant up-regulation of FSP-1 at 1 day after treatment. Furthermore, when the mTOR inhibitor rapamycin was administered with ketamine to the HBdMECs, the expression of FSP-1 decreased significantly. CONCLUSIONS: Ketamine induces activation of the mTOR pathway and subsequent mesenchymal phenotypic expression (FSP1) in HBdMECs.
Assuntos
Cistite/metabolismo , Ketamina/efeitos adversos , Microvasos/metabolismo , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Bexiga Urinária/metabolismo , Adulto , Cistite/induzido quimicamente , Feminino , Humanos , Ketamina/administração & dosagem , Masculino , Microvasos/efeitos dos fármacos , Pessoa de Meia-Idade , Fosforilação/efeitos dos fármacos , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Bexiga Urinária/efeitos dos fármacos , Adulto JovemRESUMO
BACKGROUND: The diagnosis of myeloma, a plasma dyscrasia, often results from the workup of unexplained renal disease. Persistent renal failure in myeloma is commonly caused by tubular nephropathy due to circulating immunoglobulins and free light chains. Myeloma cast nephropathy is characterized by crystalline precipitates of monoclonal light chains within distal tubules. Immunoglobulin crystallization rarely occurs intracellularly, within proximal tubular cells (light chain proximal tubulopathy) and interstitial histiocytes (crystal-storing histiocytosis). We present a case report of a rare simultaneous occurrence of light chain proximal tubulopathy, crystal-storing histiocytosis, and myeloma cast nephropathy in a patient with κ light chain multiple myeloma. CASE PRESENTATION: A 48-years-old man presented with uremia and anemia. Laboratory examination revealed low levels of serum IgG, IgA, and IgM. Serum and urine immunofixation electrophoresis showed a free κ monoclonal band. Bone marrow aspiration and biopsy revealed hypercellularity with marked plasmacytosis. Light microscopy revealed eosinophilic cuboid- and rhomboid-shaped crystals in the cytoplasm of proximal tubular epithelial cells, diffuse large mononuclear and multinuclear cells in the interstitium, and obstructed distal tubules with cast and giant cell reaction. Immunohistochemical examination indicated intense staining for κ light chains within casts, histiocytes, and tubular epithelial cells. Electron microscopy revealed electro-dense cuboid-, rhomboid-, or needle-shaped crystalline inclusions in proximal tubular epithelial cells and interstitial histiocytes. According to these results, we confirmed that this patient with myeloma exhibited simultaneous light chain proximal tubulopathy, crystal-storing histiocytosis, and myeloma cast nephropathy, which were attributed to monoclonal κ light chains. In addition to dialysis, the patient received induction chemotherapy with a combination of bortezomib, cyclophosphamide, and dexamethasone, followed by maintenance therapy with thalidomide. However, the patient did not regain renal function even when less than 5% plasma cells were detected in the bone marrow. CONCLUSION: To the best of our knowledge, this is the first report of simultaneous light chain proximal tubulopathy, crystal-storing histiocytosis, and myeloma cast nephropathy in κ light chain multiple myeloma.
Assuntos
Cadeias kappa de Imunoglobulina/sangue , Nefropatias/sangue , Nefropatias/diagnóstico por imagem , Túbulos Renais Proximais/patologia , Mieloma Múltiplo/sangue , Mieloma Múltiplo/diagnóstico , Antineoplásicos/uso terapêutico , Diagnóstico Diferencial , Histiocitose , Humanos , Cadeias kappa de Imunoglobulina/urina , Nefropatias/tratamento farmacológico , Nefropatias/prevenção & controle , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/tratamento farmacológico , Resultado do TratamentoRESUMO
BACKGROUND: Fibrillary glomerulonephritis (FGN) is a rare primary glomerular disease that seldom coexists with other diseases. Membranoproliferative glomerulonephritis is a pathologic finding of renal lesions associated with IgM-secreting monoclonal proliferations. We present a case study of a patient with unusual simultaneous FGN and IgM-related renal disorder in nonmalignant monoclonal IgM gammopathy. CASE PRESENTATION: A 63-year-old male presented with nephrotic syndrome and elevated serum creatinine levels. Laboratory examination revealed elevated levels of serum IgM and low C3 levels. Serum and urine immunofixation electrophoresis showed a monoclonal IgM with a kappa light chain. A bone marrow biopsy revealed less than 5 % bone marrow infiltration by lymphoplasmacytic lymphoma, and a renal biopsy revealed mesangiocapillary glomerulonephritis on light microscopy. Immunofluorescent and immunohistochemical staining indicated granular deposits of immunoglobulin G in the mesangium and granular deposits of immunoglobulin M and κ light chains along the capillary wall. Electron microscopy revealed randomly arranged nonbranching fibrils of approximately 15 nm in diameter in the glomerular mesangium and subendothelial electron-dense deposits. According to these results, we confirmed FGN and membranoproliferative glomerulonephritis, which were attributed to monoclonal IgM deposits. CONCLUSION: To the best of our knowledge, this is the first report of simultaneous FGN and membranoproliferative glomerulonephritis in nonmalignant IgM monoclonal gammopathy.
Assuntos
Glomerulonefrite/etiologia , Glomerulonefrite/metabolismo , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Gamopatia Monoclonal de Significância Indeterminada/complicações , Glomerulonefrite/patologia , Glomerulonefrite Membranoproliferativa/etiologia , Glomerulonefrite Membranoproliferativa/metabolismo , Glomerulonefrite Membranoproliferativa/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Gamopatia Monoclonal de Significância Indeterminada/sangue , Síndrome Nefrótica/etiologiaRESUMO
Diabetic kidney disease (DKD) is a microvascular complication that leads to kidney dysfunction and ESRD, but the underlying mechanisms remain unclear. Podocyte Wnt-pathway activation has been demonstrated to be a trigger mechanism for various proteinuric diseases. Notably, four-and-a-half LIM domains protein 2 (FHL2) is highly expressed in urogenital systems and has been implicated in Wnt/ß-catenin signaling. Here, we used in vitro podocyte culture experiments and a streptozotocin-induced DKD model in FHL2 gene-knockout mice to determine the possible role of FHL2 in DKD and to clarify its association with the Wnt pathway. In human and mouse kidney tissues, FHL2 protein was abundantly expressed in podocytes but not in renal tubular cells. Treatment with high glucose or diabetes-related cytokines, including angiotensin II and TGF-ß1, activated FHL2 protein and Wnt/ß-catenin signaling in cultured podocytes. This activation also upregulated FHL2 expression and promoted FHL2 translocation from cytosol to nucleus. Genetic deletion of the FHL2 gene mitigated the podocyte dedifferentiation caused by activated Wnt/ß-catenin signaling under Wnt-On, but not under Wnt-Off, conditions. Diabetic FHL2(+/+) mice developed markedly increased albuminuria and thickening of the glomerular basement membrane compared with nondiabetic FHL2(+/+) mice. However, FHL2 knockout significantly attenuated these DKD-induced changes. Furthermore, kidney samples from patients with diabetes had a higher degree of FHL2 podocyte nuclear translocation, which was positively associated with albuminuria and progressive renal function deterioration. Therefore, we conclude that FHL2 has both structural and functional protein-protein interactions with ß-catenin in the podocyte nucleus and that FHL2 protein inhibition can mitigate Wnt/ß-catenin-induced podocytopathy.
Assuntos
Diabetes Mellitus Experimental/metabolismo , Nefropatias Diabéticas/metabolismo , Proteínas com Homeodomínio LIM/metabolismo , Proteínas Musculares/metabolismo , Podócitos/metabolismo , Fatores de Transcrição/metabolismo , Via de Sinalização Wnt , Albuminúria/etiologia , Angiotensina II/farmacologia , Animais , Desdiferenciação Celular/genética , Células Cultivadas , Nefropatias Diabéticas/complicações , Nefropatias Diabéticas/patologia , Técnicas de Inativação de Genes , Membrana Basal Glomerular/patologia , Glucose/farmacologia , Humanos , Proteínas com Homeodomínio LIM/efeitos dos fármacos , Proteínas com Homeodomínio LIM/genética , Masculino , Camundongos , Proteínas Musculares/efeitos dos fármacos , Proteínas Musculares/genética , Podócitos/efeitos dos fármacos , Transporte Proteico , Fatores de Transcrição/efeitos dos fármacos , Fatores de Transcrição/genética , Fator de Crescimento Transformador beta1/farmacologia , Via de Sinalização Wnt/efeitos dos fármacosRESUMO
Persistent high fever is one of the most typical clinical symptoms in dengue virus (DV)-infected patients. However, the source of endogenous pyrogen (eg, IL-1ß) and the signaling cascade leading to the activation of inflammasome and caspase-1, which are essential for IL-1ß and IL-18 secretion, during dengue infection have not been elucidated yet. Macrophages can be polarized into distinct phenotypes under the influence of GM-CSF or M-CSF, denoted as GM-MÏ and M-MÏ, respectively. We found that DV induced high levels of IL-1ß and IL-18 from GM-MÏ (inflammatory macrophage) and caused cell death (pyroptosis), whereas M-MÏ (resting macrophage) did not produce IL-1ß and IL-18 on DV infection even with lipopolysaccharide priming. This observation demonstrates the distinct responses of GM-MÏ and M-MÏ to DV infection. Moreover, up-regulation of pro-IL-1ß, pro-IL-18, and NLRP3 associated with caspase-1 activation was observed in DV-infected GM-MÏ, whereas blockade of CLEC5A/MDL-1, a C-type lectin critical for dengue hemorrhagic fever and Japanese encephalitis virus infection, inhibits NLRP3 inflammasome activation and pyrotopsis in GM-MÏ. Thus, DV can activate NLRP3 inflammasome via CLEC5A, and GM-MÏ plays a more important role than M-MÏ in the pathogenesis of DV infection.
Assuntos
Vírus da Dengue/fisiologia , Dengue/imunologia , Inflamassomos/imunologia , Lectinas Tipo C/fisiologia , Ativação de Macrófagos , Macrófagos/imunologia , Receptores de Superfície Celular/fisiologia , Apoptose , Permeabilidade Capilar , Proteínas de Transporte/imunologia , Inibidores de Caspase/farmacologia , Células Cultivadas/efeitos dos fármacos , Células Cultivadas/metabolismo , Dengue/genética , Endotélio Vascular/fisiologia , Febre/etiologia , Febre/fisiopatologia , Regulação da Expressão Gênica/efeitos dos fármacos , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Humanos , Interleucina-18/biossíntese , Interleucina-18/genética , Interleucina-1beta/biossíntese , Interleucina-1beta/genética , Lectinas Tipo C/antagonistas & inibidores , Lipopolissacarídeos/farmacologia , Fator Estimulador de Colônias de Macrófagos/farmacologia , Macrófagos/classificação , Macrófagos/efeitos dos fármacos , Proteína 3 que Contém Domínio de Pirina da Família NLR , RNA Interferente Pequeno/farmacologia , Receptores de Superfície Celular/antagonistas & inibidores , Fator de Necrose Tumoral alfa/biossíntese , Fator de Necrose Tumoral alfa/genética , Replicação ViralRESUMO
Uremic patients are predisposed to atrophy of the alveolar bone and narrowing of the dental pulp chamber. Such pulp chamber changes have only been diagnosed radiologically; however, this has not been supported by any pathological evidence. We used a uremic rat model with secondary hyperparathyroidism induced by 5/6 nephrectomy surgery and high-phosphate diet to examine the dental pulp and adjacent alveolar bone pathology. In addition, we collected pulp tissues for real-time PCR. We found an opposite histopathological presentation of the ossified dental pulp and the osteomalacic adjacent alveolar bone. Furthermore, pulp cells with positive staining for Thy-1, a surrogate stem cell marker, were significantly reduced in the pulp of uremic rats compared to the controls, indicating a paucity of stem cells. This was further evidenced by the reduced pulp expression of dickkopf-1 (Dkk-1), a Wnt/ß-catenin signaling inhibitor produced by mesenchymal stem cells. In contrast, expressions of receptor activator of nuclear factor κB ligand (RANKL) and RANK in uremic pulp were up-regulated, probably to counteract the ossifying process of uremic pulp. In conclusion, uremic pulp ossifications were associated with a paucity of stem cells and dysregulated Dkk-1 and RANKL signaling systems, further shifting the imbalance toward osteogenesis. Strategies to counteract such an imbalance may offer a potential therapeutic target to improve dental health in uremic patients, which warrants further interventional studies.
Assuntos
Perda do Osso Alveolar/etiologia , Processo Alveolar/patologia , Polpa Dentária/patologia , Ossificação Heterotópica/etiologia , Uremia/complicações , Animais , Densidade Óssea , Modelos Animais de Doenças , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Masculino , Osteogênese/fisiologia , Ligante RANK/metabolismo , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase em Tempo Real , Células-Tronco/patologia , Microtomografia por Raio-XRESUMO
BACKGROUND: The process of vascular calcification has been associated with the canonical Wnt/ß-catenin signalling pathway in cell cultures and animal studies. The relationship between circulating Wnt/ß-catenin inhibitors and vascular calcification in dialysis patients is unknown. The aim of this study was to investigate the associations between serum dickkopf-1 (Dkk-1) and sclerostin, two circulating inhibitors of the Wnt/ß-catenin signalling pathway, and the severity of aortic calcification (AoC) and cardiovascular outcomes in dialysis patients. METHODS: This was a prospective observational cohort study. One hundred and twenty-five patients on maintenance haemodialysis participated in the study. Serum levels of Dkk-1 and sclerostin were measured. AoC scores were calculated from plain films of both posterior-anterior and lateral views. The patients were followed up for 2 years or until death or withdrawal. RESULTS: The circulating sclerostin level was inversely associated with the severity of AoC (P = 0.035) and indicators of the bone turnover rate including serum alkaline phosphatase (ALP) (r = -0.235, P = 0.008) and intact parathyroid hormone (r = -0.523, P < 0.001). Furthermore, Cox regression analysis indicated that the patients with high circulating sclerostin levels were less likely to experience future cardiovascular events [1 pmol/L sclerostin increase, hazard ratio 0.982 (95% CI, 0.967-0.996), P = 0.015] after adjusting for a propensity score. In contrast, serum Dkk-1 was not associated with AoC and clinical outcomes. CONCLUSIONS: In long-term haemodialysis patients, circulating sclerostin but not Dkk-1 is inversely associated with AoCs and future cardiovascular events. Our findings suggest that sclerostin, as a bone-related protein, might act as a communicator between uraemic bone and vasculature.