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1.
Proc Natl Acad Sci U S A ; 119(8)2022 02 22.
Artículo en Inglés | MEDLINE | ID: mdl-35165185

RESUMEN

Developing heterogeneous catalysts with atomically dispersed active sites is vital to boost peroxymonosulfate (PMS) activation for Fenton-like activity, but how to controllably adjust the electronic configuration of metal centers to further improve the activation kinetics still remains a great challenge. Herein, we report a systematic investigation into heteroatom-doped engineering for tuning the electronic structure of Cu-N4 sites by integrating electron-deficient boron (B) or electron-rich phosphorus (P) heteroatoms into carbon substrate for PMS activation. The electron-depleted Cu-N4/C-B is found to exhibit the most active oxidation capacity among the prepared Cu-N4 single-atom catalysts, which is at the top rankings of the Cu-based catalysts and is superior to most of the state-of-the-art heterogeneous Fenton-like catalysts. Conversely, the electron-enriched Cu-N4/C-P induces a decrease in PMS activation. Both experimental results and theoretical simulations unravel that the long-range interaction with B atoms decreases the electronic density of Cu active sites and down-shifts the d-band center, and thereby optimizes the adsorption energy for PMS activation. This study provides an approach to finely control the electronic structure of Cu-N4 sites at the atomic level and is expected to guide the design of smart Fenton-like catalysts.

2.
Int J Mol Sci ; 24(3)2023 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-36769350

RESUMEN

While genetic analyses have revealed ~100 risk loci associated with osteoarthritis (OA), only eight have been linked to hand OA. Besides, these studies were performed in predominantly European and Caucasian ancestries. Here, we conducted a genome-wide association study in the Han Chinese population to identify genetic variations associated with the disease. We recruited a total of 1136 individuals (n = 420 hand OA-affected; n = 716 unaffected control subjects) of Han Chinese ancestry. We carried out genotyping using Axiom Asia Precisi on Medicine Research Array, and we employed the RegulomeDB database and RoadMap DNase I Hypersensitivity Sites annotations to further narrow down our potential candidate variants. Genetic variants identified were tested in the Geisinger's hand OA cohort selected from the Geisinger MyCode community health initiative (MyCode®). We also performed a luciferase reporter assay to confirm the potential impact of top candidate single-nucleotide polymorphisms (SNPs) on hand OA. We identified six associated SNPs (p-value = 6.76 × 10-7-7.31 × 10-6) clustered at 2p13.2 downstream of the CYP26B1 gene. The strongest association signal identified was rs883313 (p-value = 6.76 × 10-7, odds ratio (OR) = 1.76), followed by rs12713768 (p-value = 1.36 × 10-6, OR = 1.74), near or within the enhancer region closest to the CYP26B1 gene. Our findings showed that the major risk-conferring CC haplotype of SNPs rs12713768 and rs10208040 [strong linkage disequilibrium (LD); D' = 1, r2 = 0.651] drives 18.9% of enhancer expression activity. Our findings highlight that the SNP rs12713768 is associated with susceptibility to and severity of hand OA in the Han Chinese population and that the suggested retinoic acid signaling pathway may play an important role in its pathogenesis.


Asunto(s)
Osteoartritis , Vitamina A , Humanos , Ácido Retinoico 4-Hidroxilasa/genética , Estudio de Asociación del Genoma Completo , Predisposición Genética a la Enfermedad , Alelos , Osteoartritis/genética , Polimorfismo de Nucleótido Simple , Genes Reguladores , Estudios de Casos y Controles , Genotipo , China
3.
Small ; 17(6): e2007264, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33470516

RESUMEN

Developing a rapid and low cost approach to access atomically dispersed metal catalysts (ADMCs) supported by carbon is important but still challenging. Here, an electric flash strategy using high voltage for the rapid fabrication of carbon-supported ADMCs within 1 min is reported. Continuous plasma arc results in nitrogen-doped carbon ultrathin nanosheets, while an intermittent spark pulse constructs carbon hollow nanospheres via blasting effect, and both structures are decorated with atomically dispersed cobalt. The latter catalyst shows a half-wave potential of 0.887 V versus RHE (47 mV higher than commercial Pt/C) in an oxygen reduction reaction (ORR) in alkaline media. The authors' work paves the way to rapid synthesis of carbon-supported ADMCs at both low cost and mass production.

4.
Bioconjug Chem ; 31(5): 1474-1485, 2020 05 20.
Artículo en Inglés | MEDLINE | ID: mdl-32286806

RESUMEN

Exploring a combined phototherapeutic strategy to overcome the limitations of a single mode therapy and inducing high anticancer efficiency is highly promising for precision cancer nanomedicine. However, a single-wavelength laser activates dual photothermal/photodynamic therapy (PTT/PDT) treatment is still a formidable challenge. Herein, we strategically design and fabricate a multifunctional theranostic nanosystem based on chlorin e6-functionalized polydopamine (PDA) coated prussian blue/manganese dioxide nanoparticles (PB-MnO2@PDA-Ce6 NPs). Interestingly, the obtained PB-MnO2@PDA NPs not only offer an effective delivery system for Ce6 but also provide strong optical absorption in the near-infrared range, endowing high antitumor efficacy of PTT. More importantly, the as-prepared PB-MnO2@PDA-Ce6 nanoagents exhibit an effective oxygen generation, superior reactive oxygen species (ROS), and outstanding photothermal conversion ability to greatly improve PTT and PDT treatments. As a result, both in vitro and in vivo treatments guided by MR imaging on liver cancer cells reveal the complete cell/tumor eradication under a single wavelength of 660 nm laser irradiation, implying the simultaneous synergistic PDT/PTT effects triggered by PB-MnO2@PDA-Ce6 nanoplatform, which are much higher than individual treatment. Taken together, our phototherapeutic nanoagents exhibit an excellent therapeutic performance, which may act as a nanoplatform to find safe and clinically translatable routes to accelerate cancer therapeutics.


Asunto(s)
Ferrocianuros/química , Indoles/química , Rayos Infrarrojos , Compuestos de Manganeso/química , Nanopartículas/química , Óxidos/química , Oxígeno/metabolismo , Fotoquimioterapia/métodos , Polímeros/química , Línea Celular Tumoral , Diseño de Fármacos , Humanos , Indoles/farmacología , Rayos Láser , Polímeros/farmacología
5.
Small ; 15(22): e1805312, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30951252

RESUMEN

The impressive mechanical properties of natural composites, such as nacre, arise from their multiscale hierarchical structures, which span from nano- to macroscale and lead to effective energy dissipation. While some synthetic bioinspired materials have achieved the toughness of natural nacre, current production methods are complex and typically involve toxic chemicals, extreme temperatures, and/or high pressures. Here, the exclusive use of bacteria to produce nacre-inspired layered calcium carbonate-polyglutamate composite materials that reach and exceed the toughness of natural nacre, while additionally exhibiting high extensibility and maintaining high stiffness, is introduced. The extensive diversity of bacterial metabolic abilities and the possibility of genetic engineering allows for the creation of a library of bacterially produced, cost-effective, and eco-friendly composite materials.


Asunto(s)
Materiales Biomiméticos/química , Nanocompuestos/química , Carbonato de Calcio/química , Microscopía Electrónica de Rastreo , Ácido Poliglutámico/química
6.
J Clin Ultrasound ; 46(5): 361-363, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29159809

RESUMEN

Synovial chondromatosis is a rare, benign, proliferative cartilaginous lesion arising from the synovial tissue, tenosynovium, or bursal lining. We describe the case of a patient who initially presented with multiple axillary masses. Breast ultrasound (US) was requested due to the concern of a breast tumor with axillary lymph node metastases. US study was helpful and provided adequate information to suggest the diagnosis.


Asunto(s)
Condromatosis Sinovial/complicaciones , Condromatosis Sinovial/diagnóstico por imagen , Enfermedades Linfáticas/diagnóstico por imagen , Enfermedades Linfáticas/etiología , Articulación del Hombro/diagnóstico por imagen , Axila/diagnóstico por imagen , Diagnóstico Diferencial , Femenino , Humanos , Ganglios Linfáticos/diagnóstico por imagen , Persona de Mediana Edad , Ultrasonografía
7.
Langmuir ; 32(35): 8980-7, 2016 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-27556281

RESUMEN

Oxygen-sensitive photoreversible intelligent ink capable of assessment with the human eye is an ongoing demand in the modern era. In the food industry, redox-dye-based oxygen indicator films have been proposed, but the leaching of dyes from the film that contaminates the food is one unsolved issue. On the other hand, it is also highly desirable to develop rewritable paper that significantly reduces the pressure on modern society for the production and consumption of paper. Herein, we have developed an oxygen-deficient TiO2 - x/methylene blue (MB) sol without relying on external sacrificial electron donors (SEDs) for photoreversible color switching. Oxygen vacancies in TiO2 - x can work as electron donor to favor the adsorption of the substrate and improve the charge separation that is required for the redox-based color-switching system. The problems of rewriteable paper and food packaging are addressed as two sides of a single coin in this article. We have used hydroxyethyl cellulose (HEC) for rewritable paper that can significantly delay the oxidation of leuco-MB (LMB) through hydrogen bonding and retain the printed information for a long time. The dye leaching from oxygen indicator films is also significantly reduced (only 1.54%) by using furcelleran as the coating polymer that is extracted from edible red seaweed.

9.
Bioorg Med Chem Lett ; 24(23): 5439-45, 2014 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-25454268

RESUMEN

With the emergence of drug-resistant strains and the cumulative toxicities associated with current therapies, demand remains for new inhibitors of HIV-1 replication. The inhibition of HIV-1 entry is an attractive, yet underexploited therapeutic approach with implications for salvage and preexposure prophylactic regimens, as well as topical microbicides. Using the combination of a field-derived bioactive conformation template to perform virtual screening and iterative bioisosteric replacements, coupled with in silico predictions of absorption, distribution, metabolism, and excretion, we have identified new leads for HIV-1 entry inhibitors.


Asunto(s)
Inhibidores de Fusión de VIH/farmacología , VIH-1/efectos de los fármacos , Descubrimiento de Drogas , Humanos , Conformación Molecular
10.
Diagnostics (Basel) ; 13(11)2023 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-37296733

RESUMEN

Although widely used, CT-guided lung nodule localization is associated with a significant risk of complications, including pneumothorax and pulmonary hemorrhage. This study identified potential risk factors affecting the complications associated with CT-guided lung nodule localization. Data from patients with lung nodules who underwent preoperative CT-guided localization with patent blue vital (PBV) dye at Shin Kong Wu Ho-Su Memorial Hospital, Taiwan, were retrospectively collected. Logistic regression analysis, the chi-square test, and the Mann-Whitney test were used to analyze the potential risk factors for procedure-related complications. We included 101 patients with a single nodule (49 with pneumothorax and 28 with pulmonary hemorrhage). The results revealed that men were more susceptible to pneumothorax during CT-guided localization (odds ratio: 2.48, p = 0.04). Both deeper needle insertion depth (odds ratio: 1.84, p = 0.02) and nodules localized in the left lung lobe (odds ratio: 4.19, p = 0.03) were associated with an increased risk of pulmonary hemorrhage during CT-guided localization. In conclusion, for patients with a single nodule, considering the needle insertion depth and patient characteristics during CT-guided localization procedures is probably important for reducing the risk of complications.

11.
J Dent Sci ; 18(2): 814-821, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37021272

RESUMEN

Background/purpose: Emerging evidence has shown that various failures in cancer therapy, such as drug resistance, metastasis, and cancer relapse are attributed to cancer stem cells (CSCs). Also, growing attention has been paid to the regulation of non-coding RNAs in cancer stemness. Here, we aimed to investigate the contribution of LINC01296 in the modulation of oral CSCs. Materials and methods: The phenotypic assays including migration, invasion, and colony-forming abilities were carried out in CSCs of two types of oral cancer cells (SAS and GNM) following the knockdown of LINC01296. In addition, the percentage of cells expressing stemness marker, ALDH1, and drug resistance marker, ABCG2, was examined as well as the self-renewal capacity after silencing of LINC01296. Moreover, a luciferase reporter was used to validate the direct interaction between LINC01296 and miR-143. Results: Our results showed that LINC01296 was significantly overexpressed in oral cancer tissues and positively correlated with stemness markers. The phenotypic and flow cytometry assays demonstrated that suppression of LINC01296 reduced the aggressiveness, cancer stemness features, and colony-forming and self-renewal abilities in oral CSCs. Furthermore, we demonstrated that LINC01296 may enhance cancer stemness features through suppression of the effect of miR-143. Conclusion: Silencing of LINC01296 may be a promising direction for oral cancer therapy by reducing cancer stemness via regulation of miR-143.

12.
Tohoku J Exp Med ; 226(1): 19-27, 2012 01.
Artículo en Inglés | MEDLINE | ID: mdl-22156488

RESUMEN

Secondary hyperparathyroidism (SHPT) is a common complication in chronic renal disease. Osteoprotegerin (OPG), an extracellular cytokine receptor secreted by osteoblasts, can promote bone formation by inhibiting the function of osteoclasts. Hemodialysis (HD) patients have elevated serum OPG levels. OPG secretion can be suppressed with high parathyroid hormone (PTH) levels. HD patients with refractory SHPT can benefit from parathyroidectomy (PTX) treatment, but the changes of serum OPG, bone turnover markers and bone mineral density (BMD) following PTX in HD patients remain unclear. In this study, patients on maintenance HD who received PTX for refractory SHPT (n = 28) were prospectively followed for 1 year. Serum intact PTH (iPTH), alkaline phosphatase (Alk-P), and OPG were measured serially; BMD was measured pre-PTX and at 1 year after PTX. After PTX, serum iPTH levels reduced profoundly. Serum Alk-P levels increased rapidly, peaking at 2 weeks post-PTX, while serum OPG levels gradually increased at 2 weeks after PTX and peaked at 2 months. BMD improved in both femoral neck (FN; cancellous and cortical bone) and lumbar spine (LS; cancellous bone). Higher baseline iPTH levels were associated with greater FN and LS BMD improvements at one year after PTX. The increment of serum OPG was correlated with the increase in LS BMD, implying that inhibition of osteoclastic bone resorption may improve BMD within the first year after PTX. These findings suggest that PTX removes the suppressive effects of high PTH on OPG secretion, resulting in the increased serum OPG levels that may contribute to BMD improvement.


Asunto(s)
Densidad Ósea , Hiperparatiroidismo Secundario/cirugía , Fallo Renal Crónico/terapia , Osteoprotegerina/sangre , Paratiroidectomía/métodos , Diálisis Renal , Fosfatasa Alcalina , Femenino , Cuello Femoral/diagnóstico por imagen , Cuello Femoral/metabolismo , Humanos , Hiperparatiroidismo Secundario/sangre , Fallo Renal Crónico/sangre , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/metabolismo , Masculino , Menopausia , Persona de Mediana Edad , Hormona Paratiroidea/sangre , Estudios Prospectivos , Radiografía
13.
ScientificWorldJournal ; 2012: 503945, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22919331

RESUMEN

Patients on long-term dialysis may develop secondary hyperparathyroidism (SHPT) with increased serum concentrations of bone resorption markers such as the cross-linked N-telopeptide of type I collagen (NTX) and type-5b tartrate-resistant acid phosphatase (TRAP). When SHPT proves refractory to treatment, parathyroidectomy (PTX) may be needed. Renal patients on maintenance HD who received PTX for refractory SHPT (n = 23) or who did not develop refractory SHPT (control subjects; n = 25) were followed prospectively for 4 weeks. Serum intact parathyroid hormone (iPTH), NTX, TRAP, and bone alkaline phosphatase (BAP) concentrations were measured serially and correlation analyses were performed. iPTH values decreased rapidly and dramatically. BAP values increased progressively with peak increases observed at 2 weeks after surgery. NTX and TRAP values decreased concurrently and progressively through 4 weeks following PTX. A significant correlation between TRAP and NTX values was observed before PTX but not at 4 weeks after PTX. Additionally, the fractional changes in serum TRAP were larger than those in serum NTX at all times examined after PTX. Serum iPTH, TRAP, and NTX values declined rapidly following PTX for SHPT. Serum TRAP values declined to greater degrees than serum NTX values throughout the 4-week period following PTX.


Asunto(s)
Fosfatasa Ácida/metabolismo , Biomarcadores/sangre , Resorción Ósea/sangre , Colágeno Tipo I/análisis , Colágeno Tipo I/metabolismo , Hiperparatiroidismo/sangre , Isoenzimas/metabolismo , Enfermedades Renales/sangre , Paratiroidectomía , Péptidos/análisis , Péptidos/metabolismo , Humanos , Fosfatasa Ácida Tartratorresistente
14.
Ann Hum Genet ; 75(5): 575-83, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21834907

RESUMEN

We performed a genome-wide linkage analysis to identify susceptibility loci in a large six-generation extended family previously reported with early-onset osteoarthritis (OA) DNA sequencing was performed to investigate involvement of the COMP (Cartilage oligomeric matrix protein) gene in this family. The region covering D19S884, D19S226, and D19S414 on chromosome 19p following genome-wide scan from 70 individuals of this kindred showed significant linkage, with a maximum point LOD (logarithm of the odds ratio) score of 2.51 at D19S226. Direct sequencing of the COMP gene, the most plausible candidate gene in the region, identified a c.2152C>T substitution in exon 18 which resulted in a substitution of tryptophan for arginine at position 718 located in the C terminal globular domain of the gene product. A total of 26 individuals were identified with this mutation of which 21 affected individuals had the mutation, and the other five younger individuals (18.6 ± 11.3 years of age) carried the mutation without symptoms. The results indicate that COMP is the disease susceptibility gene and the c.2152C>T mutation in exon 18 could cause early-onset OA phenotypes in this kindred, which is compatible with a previous report that this mutation also causes a mild form of multiple epiphyseal dysplasia (MED).


Asunto(s)
Proteínas de la Matriz Extracelular/genética , Glicoproteínas/genética , Mutación , Osteoartritis/genética , Adolescente , Adulto , Edad de Inicio , Proteína de la Matriz Oligomérica del Cartílago , Niño , Femenino , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Humanos , Masculino , Proteínas Matrilinas
15.
Tohoku J Exp Med ; 223(3): 153-9, 2011 03.
Artículo en Inglés | MEDLINE | ID: mdl-21350317

RESUMEN

Hemodialysis patients with secondary hyperparathyroidism (SHP) suffer from excessive oxidative stress and inflammation. Vitamin D analogues are currently the first line therapy for SHP, but the influence of vitamin D treatment on inflammation and oxidative stress remains unknown. This study investigated the influence of vitamin D therapy on oxidative stress and inflammatory markers in hemodialysis patients with SHP. Twenty-five patients (mean age 58 ± 12 years, 13 males and 12 females) were enrolled in the study to receive calcitriol treatment for 16 weeks. We evaluated changes in the serum biochemical parameters, inflammatory markers [C-reactive protein (CRP) and interleukin-6 (IL-6) levels], serum oxidative stress condition [total antioxidant status (TAS)], and CD4(+) T-lymphocyte intracellular cytokines [interferon γ (IFN-γ) and interleukin-4 (IL-4)] before and at the end of the 16-week calcitriol treatment. Correlations between each of these factors were also studied. All patients with SHP had low serum 1,25-dihydroxyvitamin D(3) levels and elevated serum levels of intact parathyroid hormone (iPTH), CRP and IL-6. Twenty patients (10 males and 10 females) responded to the calcitriol therapy, with significant decrements in serum iPTH. Our results showed that calcitriol can effectively suppress iPTH secretion, reduce inflammatory markers (CRP and IL-6) and oxidative stress. It can also effectively reduce inflammatory cytokine (CD4(+) IFN-γ) and increase anti-inflammatory cytokine (CD4(+) IL-4). Interestingly, significant correlations between CD4(+) IFN-γ levels and serum iPTH levels, as well as between TAS and iPTH levels were noted. Overall, our study has demonstrated calcitriol treatment significantly attenuates inflammation and oxidative stress in hemodialysis patients with SHP.


Asunto(s)
Calcitriol/administración & dosificación , Calcitriol/uso terapéutico , Hiperparatiroidismo Secundario/complicaciones , Hiperparatiroidismo Secundario/tratamiento farmacológico , Inflamación/complicaciones , Estrés Oxidativo , Diálisis Renal , Antioxidantes/metabolismo , Linfocitos T CD4-Positivos/efectos de los fármacos , Linfocitos T CD4-Positivos/metabolismo , Calcitriol/farmacología , Femenino , Humanos , Hiperparatiroidismo Secundario/sangre , Inflamación/sangre , Inflamación/tratamiento farmacológico , Inyecciones Intravenosas , Interferón gamma/metabolismo , Interleucina-4/sangre , Espacio Intracelular/efectos de los fármacos , Espacio Intracelular/metabolismo , Masculino , Persona de Mediana Edad , Estrés Oxidativo/efectos de los fármacos , Hormona Paratiroidea/sangre
16.
Medicine (Baltimore) ; 100(46): e27842, 2021 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-34797318

RESUMEN

ABSTRACT: Intraoperative radiation therapy (IORT) is an alternative to whole breast irradiation in selected early-stage breast cancer patients. In this single institute analysis, we report the preliminary results of IORT given by Axxent Electronic Brachytherapy (eBT) system.Patients treated with lumpectomy and eBT within a minimum follow-up period of 12 months were analyzed. Eligible criteria include being over the age of 45, having unifocal invasive ductal carcinoma (IDC) or ductal carcinoma in situ <3 cm in diameter, not exhibiting lymph node involvement on preoperative images, and negative sentinel lymph node biopsy. The eBT was given by preloaded radiation plans to deliver a single fraction of 20 Gray (Gy) right after lumpectomy.From January 2016 to April 2019, a total of 103 patients were collected. There were 78 patients with IDC and 25 with ductal carcinoma in situ. At a mean follow-up time of 31.1 months (range, 14.5-54.0 months), the local control rate was 98.1%. Two IDC patients had tumor recurrences (1 local and 1 regional failure). Post-IORT radiotherapy was given to 4 patients. There were no cancer related deaths, no distant metastases, and treatment side effects greater than grade 3 documented.We report the largest single institute analysis using the eBT system in Taiwan. The low recurrence and complication rates at a 31.1 month follow-up time support the use of the eBT system in selected early-stage breast cancer patients.


Asunto(s)
Braquiterapia , Neoplasias de la Mama/radioterapia , Carcinoma Ductal de Mama/radioterapia , Carcinoma Intraductal no Infiltrante/radioterapia , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/cirugía , Carcinoma Ductal de Mama/cirugía , Carcinoma Intraductal no Infiltrante/cirugía , Femenino , Estudios de Seguimiento , Humanos , Mastectomía Segmentaria , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Resultado del Tratamiento
17.
Am J Kidney Dis ; 55(1): e1-5, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19833423

RESUMEN

Fanconi syndrome and chronic kidney disease associated with paroxysmal nocturnal hemoglobinuria is rarely reported. We describe a 51-year-old woman with glomerular filtration rate decrease and hypokalemia, glucosuria, and proteinuria during a 4-year period. Paroxysmal nocturnal hemoglobinuria was diagnosed 17 years earlier, and she has received multiple blood transfusions because of hemolytic episodes during the last 5 years. Deteriorating kidney function and persistent Fanconi syndrome were accompanied by a progressive increase in serum ferritin levels. Laboratory studies showed proximal renal tubular acidosis, hypophosphotemic hyperphosphaturia, normoglycemic glucosuria, and aminoaciduria. Serologic testing, tumor markers, Bence-Jones protein, and heavy-metal screening results were negative. Abdominal magnetic resonance imaging showed characteristic features of iron deposition in the bilateral renal cortices. Kidney biopsy showed chronic interstitial nephritis with prominent hemosiderin deposition in the proximal tubules. With potassium citrate, calcitriol, and deferoxamine therapy, Fanconi syndrome persisted, but kidney function was stable. Renal hemosiderosis secondary to both chronic repetitive hemolytic episodes and transfusion-related iron overload in patients with paroxysmal nocturnal hemoglobinuria can lead to Fanconi syndrome and chronic kidney disease.


Asunto(s)
Síndrome de Fanconi/etiología , Hemoglobinuria Paroxística/complicaciones , Hemosiderosis/complicaciones , Fallo Renal Crónico/etiología , Biopsia , Síndrome de Fanconi/diagnóstico , Síndrome de Fanconi/fisiopatología , Resultado Fatal , Femenino , Tasa de Filtración Glomerular , Hemoglobinuria Paroxística/diagnóstico , Hemoglobinuria Paroxística/fisiopatología , Hemosiderosis/diagnóstico , Hemosiderosis/fisiopatología , Humanos , Fallo Renal Crónico/diagnóstico , Fallo Renal Crónico/fisiopatología , Túbulos Renales Proximales/ultraestructura , Imagen por Resonancia Magnética , Microscopía Electrónica , Persona de Mediana Edad
18.
South Med J ; 103(6): 570-3, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20710144

RESUMEN

Osteomalacia can be a late but unrecognized complication following jejunoileal bypass. We describe a 53-year-old man who underwent jejunoileal bypass for morbid obesity twenty years earlier who suffered from progressive diffuse bony pain refractory to nonsteroidal anti-inflammatory drugs. He was initially diagnosed with a malignancy with bone metastasis. However, pertinent laboratory data were notable for hypocalcemia (7.5 mg/dL, albumin 4.1 mg/dL) with low urinary calcium excretion (14 mg/day), hypophosphatemia (2.0 mg/dL) with low urinary phosphate excretion (53 mg/day), hypomagnesemia (1.5 mg/dL) with low urine magnesium excretion (23 mg/day), low 1, 25 (OH)2 vitamin D3, and elevated serum alkaline phosphatase and intact parathyroid hormone (iPTH). These laboratory findings pointed to a defect in calcium, phosphate, and magnesium handling in the gastrointestinal tract. Bone biopsy of the iliac crest clearly demonstrated typical changes of osteomalacia with excessive osteoid accumulation and reduced mineralization. His clinical symptoms were refractory to oral 1, 25 (OH)2 vitamin D3 and calcium supplementation but significantly improved with the addition of intermittent intravenous active 1, 25 (OH)2 vitamin D3, calcium, phosphate, and magnesium supplementation. Osteomalacia is an easily misdiagnosed late complication of jejunoileal bypass. Early recognition can avoid circuitous diagnosis and inappropriate management.


Asunto(s)
Dolor en el Pecho/etiología , Cadera , Derivación Yeyunoileal/efectos adversos , Osteomalacia/diagnóstico , Osteomalacia/etiología , Dolor Postoperatorio/etiología , Dolor de Hombro/etiología , Biopsia , Dolor en el Pecho/patología , Diagnóstico Diferencial , Cadera/patología , Humanos , Ilion/patología , Masculino , Persona de Mediana Edad , Osteomalacia/patología , Dolor Postoperatorio/diagnóstico , Dolor Postoperatorio/patología , Dolor Postoperatorio/terapia , Cuidados Posoperatorios , Cintigrafía , Dolor de Hombro/patología , Medronato de Tecnecio Tc 99m
19.
ACS Nano ; 14(11): 14731-14739, 2020 11 24.
Artículo en Inglés | MEDLINE | ID: mdl-33146012

RESUMEN

Graphene oxide (GO) has recently been highlighted as a promising multipurpose two-dimensional material. However, free-standing graphene oxide films suffer from poor strength and flexibility, which limits scaling-up of production and lifetime structural robustness in applications. Inspired by the relationship between the organic and inorganic components of the hierarchical structure of nacre found in mollusk shells, we have fabricated self-assembled, layered graphene-based composite films. The organic phase of our composite is produced via environmentally friendly and economical methods based on bacterial production of γ-poly(glutamic acid) (PGA). Composite films made of GO, PGA, and divalent cations (Ca2+) were prepared through a slow solvent evaporation method at ambient temperature, resulting in a nacre-like layered structure. These biobased nanocomposite films showed impressive mechanical properties, which resulted from a synergistic combination of hydrogen bonding with the bacterially produced PGA and ionic bonding with calcium ions (Ca2+). The GO/PGA/Ca2+ composite films possessed a high strength of 150 ± 51.9 MPa and a high Young's modulus of 21.4 ± 8.7 GPa, which represents an increase of 120% and over 70% with respect to pure GO films. We provide rational design strategies for the production of graphene-based films with improved mechanical performance, which can be applied in filtration purification of wastewater in the paper, food, beverage, pigment, and pharmaceuticals industries, as well as for manufacturing of functional membranes and surface coatings.


Asunto(s)
Grafito , Nácar , Nanocompuestos , Polímeros
20.
Rheumatology (Oxford) ; 48(4): 371-4, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19223283

RESUMEN

OBJECTIVES: To characterize a large extended family with early-onset OA of the knee and investigate its associations with the COL2A1 gene. METHODS: Phenotype assessments were conducted in a six-generation family to identify individuals affected with OA. Short tandem repeat polymorphic (STRP) markers and DNA sequencing were performed to investigate the involvement of the COL2A1 gene in this family. RESULTS: The kindred affected with OA showed autosomal dominant inheritance. The mean age of onset was 37.3 +/- 19.2, 29.8 +/- 13.7 and 12.0 +/- 7.2 years for generations IV, V and VI, respectively, and 25 +/- 16.1 years for males and 34.3 +/- 15.5 years for females. The height of the affected males was shorter than the unaffected males (155.9 +/- 11.4 vs 164.5 +/- 16.0 cm, P = 0.010). Arm span in the affected males was also significantly shorter than the unaffected males (158.4 +/- 12.5 vs 165.3 +/- 16.7 cm, P = 0.027). However, both height and arm span were not reduced in the affected female OA patients. STRP markers surrounding COL2A1 locus did not show linkage of the COL2A1 locus with the OA. Sequencing of COL2A1 gene revealed three single nucleotide polymorphisms but no mutation was found in the affected patients. CONCLUSIONS: The COL2A1 was not a susceptibility gene responsible for the OA phenotype in a large extended kindred with familial early-onset OA. The availability of DNA samples will allow genome-wide linkage study to identify the susceptibility locus.


Asunto(s)
Colágeno Tipo II/genética , Osteoartritis/genética , Polimorfismo de Nucleótido Simple , Adulto , Edad de Inicio , Anciano , Mapeo Cromosómico , Femenino , Genes Dominantes , Genotipo , Articulación de la Cadera/diagnóstico por imagen , Humanos , Articulación de la Rodilla/diagnóstico por imagen , Masculino , Osteoartritis/diagnóstico por imagen , Osteoartritis de la Cadera/diagnóstico por imagen , Osteoartritis de la Cadera/genética , Osteoartritis de la Rodilla/diagnóstico por imagen , Osteoartritis de la Rodilla/genética , Linaje , Fenotipo , Radiografía , Análisis de Secuencia de ADN
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