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1.
Open Forum Infect Dis ; 10(7): ofad344, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37520411

RESUMO

Background: Five hundred milligrams of intravenous (IV) sotrovimab has been shown to be well tolerated and efficacious against pre-Omicron strains in treating patients with mild to moderate coronavirus disease 2019 (COVID-19) at high risk for disease progression. Methods: This was an open-label, single-arm substudy of phase 3 COMET-TAIL (NCT04913675) assessing the safety and tolerability of a 2000 mg IV dose of sotrovimab. Symptomatic patients (aged ≥18 years) with COVID-19 at high risk for progression were enrolled from June 30 through July 11, 2022, when Omicron BA.5, BA.2.12.1, and BA.4 were the predominant circulating variants in the United States. The primary end point was the occurrence of adverse events (AEs), serious AEs (SAEs), AEs of special interest, and COVID-19 disease-related events (DREs) through day 8. Safety, pharmacokinetics, viral load, and hospitalization >24 hours for acute management of illness or death through day 29 were assessed. Results: All participants (n = 81) were Hispanic, 58% were female, and 51% were aged ≥55 years. Through day 8, no AEs, including infusion-related reactions or hypersensitivity, were reported; 2 participants reported DREs (mild cough, n = 2). One SAE (acute myocardial infarction), which was considered unrelated to sotrovimab or COVID-19 by the investigator, occurred on day 27 and was the only hospitalization reported. Maximum serum concentration (geometric mean) was 745.9 µg/mL. Viral load decreased from baseline through day 29; only 2 (3%) participants had a persistently high viral load (≥4.1 log10 copies/mL) at day 8. Conclusions: Two thousand milligrams of IV sotrovimab was well tolerated, with no safety signals observed. Trial registration: ClinicalTrials.gov Identifier: NCT04913675.

2.
J Card Surg ; 37(9): 2867-2872, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35819367

RESUMO

Modern inferior vena cava filters (IVCFs) are intended to be retrieved once a thrombotic process or risk of pulmonary embolism has resolved independent of administration of anticoagulation. IVCF removal can be challenging with the risk of complications including venous perforation, filter migration, and device fracture. IVCF removal has been described using the nomenclature of routine versus advanced retrieval. Routine retrieval is defined as accessing the filter hook with a loop snare device before advancing a sheath over the filter. Advanced retrieval techniques are employed when routine retrieval fails and can refer to a variety of approaches, including filter realignment with loop snare, stiff wire-displacement, use of a wire and snare with dual access, angioplasty balloon advanced over a guidewire, single access sling approach, the sandwich technique, the endobronchial forceps dissection and removal, photothermic ablation with excimer laser, and the filter eversion technique among others. Successful routine retrieval of IVCF has been reported at 74% and IVCF retrieval with advanced techniques has a success rate of nearly 95%. The complication rate with advanced techniques is higher when compared with routine techniques (5.3% vs. 0.4%; p < .05) and, as expected, requires fluoroscopic time. We report two cases of advanced filter retrieval using endobronchial forceps simultaneously or sequentially through the transfemoral and trans-jugular approach.


Assuntos
Embolia Pulmonar , Filtros de Veia Cava , Remoção de Dispositivo/métodos , Humanos , Embolia Pulmonar/etiologia , Embolia Pulmonar/prevenção & controle , Estudos Retrospectivos , Instrumentos Cirúrgicos/efeitos adversos , Resultado do Tratamento , Filtros de Veia Cava/efeitos adversos , Veia Cava Inferior
4.
Environ Microbiol Rep ; 13(4): 458-463, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33185975

RESUMO

We surveyed Spartina saltmarsh sediment rhizosphere fungal communities at three saltmarshes and two timepoints in coastal Nova Scotia. Based on ITS2 Illumina miSeq rDNA data and multivariate analysis, neither sediment zone nor collection period correlated with fungal ASV richness, but collection site did. However, Shannon diversity indicated that sediment zone played a significant role in fungal diversity. For unweighted and weighted UniFrac distance, site was the major factor driving beta-diversity, with sediment zone and collection period having smaller roles. Sediment type and saltmarsh plant species may play important roles in structuring rhizosphere fungal assemblages, here dominated by ascomycetes. To our knowledge, our study is the first to assess fungal sediment communities in saltmarshes in Atlantic Canada using metabarcoding. It provides a biodiversity analysis of sediment fungi in a poorly studied but highly important ecosystem and points to their roles in nutrient cycling, blue carbon, coastal stability and coastal restoration. Our work will inform ongoing saltmarsh restoration in Atlantic Canada.


Assuntos
Ascomicetos , Micobioma , Ecossistema , Fungos/genética , Nova Escócia , Rizosfera , Microbiologia do Solo
5.
J Pediatr Surg ; 55(10): 2170-2176, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32115227

RESUMO

BACKGROUND: The guide for monitoring and treatment of congenital hepatic hemangiomas (CHH) will depend on the subtype and the postnatal clinical behavior. Our aim is to present a series of CHH and characterize its clinical, histologic and genetic correlation, compared to cutaneous congenital hemangiomas (CCH). MATERIAL AND METHODS: A retrospective review of CHH patients diagnosed between 1991 and 2018 was performed. Clinical, morphological and histological data were analyzed and deep high-throughput sequencing was performed. MAIN RESULTS: Sixteen patients with CHH were included. Five patients were followed up with serial ultrasounds while pharmacological treatment (corticosteroids and propranolol) was decided in five. Surgical resection was performed in five owing to hemorrhage and suspicion of malignancy, and the last patient underwent embolization. Histologic analysis was available in 7 patients and confirmed CHH, showing two different histological patterns that could be associated with the presence of somatic pathogenic variants in GNAQ and/or PIK3CA detected in the genetic testing. Review of 7 samples of CCH revealed some histologic differences compared to CHH. CONCLUSION: CHH resemble its cutaneous homonym with similar clinical behavior. Histologic analysis can differentiate two subgroups while genetic testing can confirm mutations in GNAQ and in PIK3CA in a subset of CHH. TYPE OF STUDY: Treatment study. LEVEL OF EVIDENCE: IV.


Assuntos
Hemangioma/genética , Hemangioma/patologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Neoplasias Cutâneas/patologia , Classe I de Fosfatidilinositol 3-Quinases/genética , Feminino , Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP/genética , Testes Genéticos , Hemangioma/congênito , Hemangioma/terapia , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Lactente , Recém-Nascido , Neoplasias Hepáticas/congênito , Neoplasias Hepáticas/terapia , Masculino , Mutação , Estudos Retrospectivos , Análise de Sequência de DNA , Neoplasias Cutâneas/congênito
6.
Mol Pharm ; 16(4): 1433-1443, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30803231

RESUMO

Glioblastoma (GBMs) is the most common and aggressive type of primary brain tumor in adults with dismal prognosis despite radical surgical resection coupled with chemo- and radiotherapy. Recent studies have proposed the use of small-molecule inhibitors, including verteporfin (VP), to target oncogenic networks in cancers. Here we report efficient encapsulation of water-insoluble VP in poly(lactic- co-glycolic acid) microparticles (PLGA MP) of ∼1.5 µm in diameter that allows tunable, sustained release. Treatment with naked VP and released VP from PLGA MP decreased cell viability of patient-derived primary GBM cells in vitro by ∼70%. Moreover, naked VP treatment significantly increased radiosensitivity of GBM cells, thereby enhancing overall tumor cell killing ability by nearly 85%. Our in vivo study demonstrated that two intratumoral administrations of sustained slow-releasing VP-loaded PLGA MPs separated by two weeks significantly attenuated tumor growth by ∼67% in tumor volume in a subcutaneous patient-derived GBM xenograft model over 26 d. Additionally, our in vitro data indicate broader utility of VP for treatment for other solid cancers, including chordoma, malignant meningioma, and various noncentral nervous system-derived carcinomas. Collectively, our work suggests that the use of VP-loaded PLGA MP may be an effective local therapeutic strategy for a variety of solid cancers, including unresectable and orphan tumors, which may decrease tumor burden and ultimately improve patient prognosis.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Glioblastoma/tratamento farmacológico , Microesferas , Fármacos Fotossensibilizantes/farmacologia , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Polímeros/química , Verteporfina/farmacologia , Animais , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Ácido Láctico/química , Masculino , Camundongos , Camundongos Nus , Poliésteres/química , Ácido Poliglicólico/química , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Clin Genet ; 95(4): 516-519, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30635911

RESUMO

Capillary malformation-arteriovenous malformation (CM-AVM) is caused by germline RASA1 and EPHB4 alterations. RASA1 intralesional second hits have also been reported. Here we report RASA1 constitutional mosaicism, defined here as the presence of a mosaic variant in all cell types of an individual, in two patients with CM-AVM. High-throughput sequencing was used to search for RASA1 pathogenic variants in blood samples from two unrelated patients with CM-AVM. An affected tissue sample from one of the patients was also analyzed. Both patients showed different nonsense RASA1 variants in mosaic, ranging from 7% to 21.5%, in blood samples and in the corresponding affected tissue sample from one of the patients. In conclusion, we report for the first time the presence of RASA1 constitutional mosaicism in CM-AVM. Constitutional mosaicism has implications for accurate molecular diagnosis and recurrence risk and helps to explain the great phenotypic variability in CM-AVM.


Assuntos
Malformações Arteriovenosas/diagnóstico , Malformações Arteriovenosas/genética , Capilares/anormalidades , Estudos de Associação Genética , Predisposição Genética para Doença , Mosaicismo , Mutação , Mancha Vinho do Porto/diagnóstico , Mancha Vinho do Porto/genética , Proteína p120 Ativadora de GTPase/genética , Alelos , Substituição de Aminoácidos , Angiografia por Tomografia Computadorizada , Feminino , Estudos de Associação Genética/métodos , Genótipo , Humanos , Masculino
8.
J Exp Med ; 216(2): 407-418, 2019 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-30591517

RESUMO

Generalized lymphatic anomaly (GLA) is a vascular disorder characterized by diffuse or multifocal lymphatic malformations (LMs). The etiology of GLA is poorly understood. We identified four distinct somatic PIK3CA variants (Glu542Lys, Gln546Lys, His1047Arg, and His1047Leu) in tissue samples from five out of nine patients with GLA. These same PIK3CA variants occur in PIK3CA-related overgrowth spectrum and cause hyperactivation of the PI3K-AKT-mTOR pathway. We found that the mTOR inhibitor, rapamycin, prevented lymphatic hyperplasia and dysfunction in mice that expressed an active form of PIK3CA (His1047Arg) in their lymphatics. We also found that rapamycin reduced pain in patients with GLA. In conclusion, we report that somatic activating PIK3CA mutations can cause GLA, and we provide preclinical and clinical evidence to support the use of rapamycin for the treatment of this disabling and deadly disease.


Assuntos
Classe I de Fosfatidilinositol 3-Quinases , Linfangioleiomiomatose , Sistema Linfático , Mutação de Sentido Incorreto , Sirolimo/administração & dosagem , Adolescente , Adulto , Substituição de Aminoácidos , Criança , Pré-Escolar , Classe I de Fosfatidilinositol 3-Quinases/genética , Classe I de Fosfatidilinositol 3-Quinases/metabolismo , Feminino , Humanos , Linfangioleiomiomatose/diagnóstico por imagem , Linfangioleiomiomatose/tratamento farmacológico , Linfangioleiomiomatose/enzimologia , Linfangioleiomiomatose/genética , Sistema Linfático/anormalidades , Sistema Linfático/diagnóstico por imagem , Sistema Linfático/enzimologia , Masculino , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo
9.
Surgery ; 164(2): 262-273, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29731246

RESUMO

BACKGROUND: GDF11 modulates embryonic patterning and kidney organogenesis. Herein, we sought to define GDF11 function in the adult kidney and in renal diseases. METHODS: In vitro renal cell lines, genetic, and murine in vivo renal injury models were examined. RESULTS: Among tissues tested, Gdf11 was highest in normal adult mouse kidney. Expression was increased acutely after 5/6 nephrectomy, ischemia-reperfusion injury, kanamycin toxicity, or unilateral ureteric obstruction. Systemic, high-dose GDF11 administration in adult mice led to renal failure, with accompanying kidney atrophy, interstitial fibrosis, epithelial-to-mesenchymal transition of renal tubular cells, and eventually death. These effects were associated with phosphorylation of SMAD2 and could be blocked by follistatin. In contrast, Gdf11 heterozygous mice showed reduced renal Gdf11 expression, renal fibrosis, and expression of fibrosis-associated genes both at baseline and after unilateral ureteric obstruction compared with wild-type littermates. The kidney-specific consequences of GDF11 dose modulation are direct effects on kidney cells. GDF11 induced proliferation and activation of NRK49f renal fibroblasts and also promoted epithelial-to-mesenchymal transition of IMCD-3 tubular epithelial cells in a SMAD3-dependent manner. CONCLUSION: Taken together, these data suggest that GDF11 and its downstream signals are critical in vivo mediators of renal injury. These effects are through direct actions of GDF11 on renal tubular cells and fibroblasts. Thus, regulation of GDF11 presents a therapeutic target for diseases involving renal fibrosis and impaired tubular function.


Assuntos
Proteínas Morfogenéticas Ósseas/fisiologia , Transição Epitelial-Mesenquimal , Fatores de Diferenciação de Crescimento/fisiologia , Nefroesclerose/etiologia , Insuficiência Renal/etiologia , Animais , Linhagem Celular , Feminino , Folistatina , Rim/patologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Nus , Insuficiência Renal/patologia , Proteína Smad2/metabolismo
10.
Genet Med ; 20(8): 882-889, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29446767

RESUMO

PURPOSE: CLAPO syndrome is a rare vascular disorder characterized by capillary malformation of the lower lip, lymphatic malformation predominant on the face and neck, asymmetry, and partial/generalized overgrowth. Here we tested the hypothesis that, although the genetic cause is not known, the tissue distribution of the clinical manifestations in CLAPO seems to follow a pattern of somatic mosaicism. METHODS: We clinically evaluated a cohort of 13 patients with CLAPO and screened 20 DNA blood/tissue samples from 9 patients using high-throughput, deep sequencing. RESULTS: We identified five activating mutations in the PIK3CA gene in affected tissues from 6 of the 9 patients studied; one of the variants (NM_006218.2:c.248T>C; p.Phe83Ser) has not been previously described in developmental disorders. CONCLUSION: We describe for the first time the presence of somatic activating PIK3CA mutations in patients with CLAPO. We also report an update of the phenotype and natural history of the syndrome.


Assuntos
Malformações Arteriovenosas/genética , Malformações Arteriovenosas/fisiopatologia , Classe I de Fosfatidilinositol 3-Quinases/genética , Doenças Linfáticas/genética , Doenças Linfáticas/fisiopatologia , Adolescente , Adulto , Criança , Classe I de Fosfatidilinositol 3-Quinases/fisiologia , Feminino , Estudos de Associação Genética/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Masculino , Mutação , Fosfatidilinositol 3-Quinases/genética , Estudos Retrospectivos
11.
Cell Rep ; 21(2): 495-507, 2017 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-29020634

RESUMO

Molecular factors that define stem cell identity have recently emerged as oncogenic drivers. For instance, brachyury, a key developmental transcriptional factor, is also implicated in carcinogenesis, most notably of chordoma, through mechanisms that remain elusive. Here, we show that brachyury is a crucial regulator of stemness in chordoma and in more common aggressive cancers. Furthermore, this effect of brachyury is mediated by control of synthesis and stability of Yes-associated protein (YAP), a key regulator of tissue growth and homeostasis, providing an unexpected mechanism of control of YAP expression. We further demonstrate that the brachyury-YAP regulatory pathway is associated with tumor aggressiveness. These results elucidate a mechanism of controlling both tumor stemness and aggressiveness through regulatory coupling of two developmental factors.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Carcinogênese/genética , Proteínas Fetais/metabolismo , Regulação Neoplásica da Expressão Gênica , Células-Tronco Neoplásicas/metabolismo , Fosfoproteínas/metabolismo , Proteínas com Domínio T/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Carcinogênese/metabolismo , Carcinoma/genética , Carcinoma/metabolismo , Linhagem Celular Tumoral , Neoplasias do Sistema Nervoso Central/genética , Neoplasias do Sistema Nervoso Central/metabolismo , Condroma/genética , Condroma/metabolismo , Condroma/patologia , Proteínas Fetais/genética , Glioblastoma/genética , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Camundongos , Fosfoproteínas/genética , Proteínas com Domínio T/genética , Fatores de Transcrição , Proteínas de Sinalização YAP
12.
Obes Surg ; 26(5): 1016-20, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26386880

RESUMO

BACKGROUND: Along with the development of technology, robotic approach is being performed for laparoscopic Roux-en-Y gastric bypass (LRYGB). Some literatures reported same or better peri-operative outcomes with the robotic procedure. The aim of this study is to compare our experience in robot-assisted LRYGB (RA-LRYGB) with LRYGB in terms of peri-operative outcomes. METHODS: From January 1, 2012 to April 30, 2014, a total of 270 patients underwent LRYGB by one surgeon at a single institution. Of these, 64 cases were done robotically. A retrospective review was performed for these patients, noting the outcomes and complications of the procedure. RESULTS: The 64 RA-LRYGB patients had a mean age of 45.9 ± 10.0 years (range, 23-67) and a mean preoperative body mass index (BMI) of 48.4 ± 7.9 kg/m(2) (range, 33.8-76.4). The 207 LRYGB patients had a mean age of 45.0 ± 10.7 years (range, 21-67) and a mean preoperative BMI of 48.4 ± 8.1 kg/m(2) (range, 34.0-80.4). These two groups were clinically comparable. Mean length of hospital stay was 3.0 ± 4.1 days (range, 1-19) in RA-LRYGB patients, significantly longer than 1.6 ± 1.7 days (range, 1-17) in LRYGB patients (p < 0.01). Thirty-day readmission rate was 9.3% (n = 6) in the RA-LRYGB group and 6.8% (n = 14) in the LRYGB group. Higher leak rate was noticed in RA-LRYGB patients at 7.8% (n = 5), compared to 0.5% (n = 1) in LRYGB patients (p < 0.01). All the leaks occurred at the pouch level in the RA-LRYGB group, while one leak from the LRYGB group occurred at the gastrojejunal anastomosis site. CONCLUSIONS: Robot-assisted Roux-en-Y gastric bypass may result in higher leak rate at the pouch level, when compared to that of laparoscopic procedures.


Assuntos
Derivação Gástrica/efeitos adversos , Laparoscopia/efeitos adversos , Obesidade Mórbida/epidemiologia , Obesidade Mórbida/cirurgia , Complicações Pós-Operatórias/epidemiologia , Procedimentos Cirúrgicos Robóticos/efeitos adversos , Adulto , Idoso , Feminino , Derivação Gástrica/métodos , Humanos , Laparoscopia/métodos , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
13.
Arch Cardiol Mex ; 86(1): 18-25, 2016.
Artigo em Espanhol | MEDLINE | ID: mdl-26256255

RESUMO

UNLABELLED: The use of coronary stents in coronary angioplasty has evolved dramatically in its design, type materials, polymers, and a variety of drugs, the use of coronary stents covered nitric oxide have shown satisfactory results in practice, however compared to the results reported drug-eluting stents, there is little information. OBJECTIVES: The aim of this study was to compare clinical outcomes of a stainless steel stent Bioactive nitric oxide coated titanium (BAS) and a drug-eluting stent zotarolimus (DES) in daily clinical practice. METHODS: A retrospective, analytical, descriptive and comparative study aimed at evaluating the safety and efficacy of two devices with different characteristics in our population. The primary endpoints were: death, acute infarction (AMI), and re intervention injury Treated (RLT). RESULTS: A total of 759 patients were included in the study which was performed angioplasty to a single vessel. Were divided into two arms 382 with DES and 377 patients with BAS, the one year follow up was carried in 95%. After this follow-up period, primary points (cardiovascular death, myocardial infarction, TLR and stent thrombosis) for arm DES vs BAS; 9.5% vs 8.5% P=NS but with shorter periods of dual antiplatelet therapy for arm BAS 6.9±4.1 vs 11.1±2.5 months DES P=.0001. The results were independent of the clinical syndrome of presentation. CONCLUSIONS: After one year of follow no statistically significant difference in major clinical events, there was a trend in favour of BAS vs SM with respect to revascularization of the target lesion without reaching statistical significance.


Assuntos
Stents Farmacológicos , Isquemia Miocárdica/cirurgia , Revascularização Miocárdica/métodos , Óxido Nítrico/administração & dosagem , Sirolimo/análogos & derivados , Titânio/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Desenho de Prótese , Estudos Retrospectivos , Sirolimo/administração & dosagem , Resultado do Tratamento
14.
Curr Pediatr Rev ; 11(3): 226-32, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26168941

RESUMO

Neonatal vascular tumours present particular difficulties in their diagnosis and treatment. The special behaviour of neonatal hemangioma and the aggressive but benign nature of kaposiform hemangioendothelioma provide examples of a modern need for a conservative approach. Recent advances in their pharmacological management have dramatically changed the therapeutical scope of this group of tumors with surgery playing a minor role in their treatment. Multidisciplinary teams management involving neonatology, pediatric surgery, dermatology, pathology, genetics and radiology specialists among others remains the best option for an optimal outcome.


Assuntos
Hemangioendotelioma/diagnóstico , Hemangioma/diagnóstico , Síndrome de Kasabach-Merritt/diagnóstico , Sarcoma de Kaposi/diagnóstico , Neoplasias Cutâneas/diagnóstico , Protocolos de Quimioterapia Combinada Antineoplásica , Diagnóstico Diferencial , Hemangioendotelioma/patologia , Hemangioendotelioma/terapia , Hemangioma/patologia , Hemangioma/terapia , Humanos , Recém-Nascido , Doenças do Recém-Nascido , Síndrome de Kasabach-Merritt/patologia , Síndrome de Kasabach-Merritt/terapia , Prognóstico , Sarcoma de Kaposi/patologia , Sarcoma de Kaposi/terapia , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/terapia
15.
Int J Biol Sci ; 11(4): 456-71, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25798065

RESUMO

The metal binding preference of metallothioneins (MTs) groups them in two extreme subsets, the Zn/Cd- and the Cu-thioneins. Ciliates harbor the largest MT gene/protein family reported so far, including 5 paralogs that exhibit relatively low sequence similarity, excepting MTT2 and MTT4. In Tetrahymena thermophila, three MTs (MTT1, MTT3 and MTT5) were considered Cd-thioneins and two (MTT2 and MTT4) Cu-thioneins, according to gene expression inducibility and phylogenetic analysis. In this study, the metal-binding abilities of the five MTT proteins were characterized, to obtain information about the folding and stability of their cognate- and non-cognate metal complexes, and to characterize the T. thermophila MT system at protein level. Hence, the five MTTs were recombinantly synthesized as Zn(2+)-, Cd(2+)- or Cu(+)-complexes, which were analyzed by electrospray mass spectrometry (ESI-MS), circular dichroism (CD), and UV-vis spectrophotometry. Among the Cd-thioneins, MTT1 and MTT5 were optimal for Cd(2+) coordination, yielding unique Cd17- and Cd8- complexes, respectively. When binding Zn(2+), they rendered a mixture of Zn-species. Only MTT5 was capable to coordinate Cu(+), although yielding heteronuclear Zn-, Cu-species or highly unstable Cu-homometallic species. MTT3 exhibited poor binding abilities both for Cd(2+) and for Cu(+), and although not optimally, it yielded the best result when coordinating Zn(2+). The two Cu-thioneins, MTT2 and MTT4 isoforms formed homometallic Cu-complexes (major Cu20-MTT) upon synthesis in Cu-supplemented hosts. Contrarily, they were unable to fold into stable Cd-complexes, while Zn-MTT species were only recovered for MTT4 (major Zn10-MTT4). Thus, the metal binding preferences of the five T. thermophila MTs correlate well with their previous classification as Cd- and Cu-thioneins, and globally, they can be classified from Zn/Cd- to Cu-thioneins according to the gradation: MTT1>MTT5>MTT3>MTT4>MTT2. The main mechanisms underlying the evolution and specialization of the MTT metal binding preferences may have been internal tandem duplications, presence of doublet and triplet Cys patterns in Zn/Cd-thioneins, and optimization of site specific amino acid determinants (Lys for Zn/Cd- and Asn for Cu-coordination).


Assuntos
Metalotioneína/metabolismo , Tetrahymena thermophila/metabolismo , Cobre/metabolismo , Ligação Proteica , Especificidade por Substrato , Zinco/metabolismo
16.
Front Microbiol ; 6: 48, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25750637

RESUMO

This review analyzes the advantages and disadvantages of using eukaryotic microorganisms to design whole-cell biosensors (WCBs) for monitoring environmental heavy metal pollution in soil or aquatic habitats. Basic considerations for designing a eukaryotic WCB are also shown. A comparative analysis of the promoter genes used to design WCBs is carried out, and the sensitivity and reproducibility of the main reporter genes used is also reviewed. Three main eukaryotic taxonomic groups are considered: yeasts, microalgae, and ciliated protozoa. Models that have been widely analyzed as potential WCBs are the Saccharomyces cerevisiae model among yeasts, the Tetrahymena thermophila model for ciliates and Chlamydomonas model for microalgae. The advantages and disadvantages of each microbial group are discussed, and a ranking of sensitivity to the same type of metal pollutant from reported eukaryotic WCBs is also shown. General conclusions and possible future developments of eukaryotic WCBs are reported.

17.
Semin Pediatr Surg ; 23(5): 298-302, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25459015

RESUMO

Leakage of lymph from the lymphatic ducts causes chylothorax (CT) or chylous ascitis (CA). This may happen for unknown reasons during fetal life or after birth and may also be caused by trauma after thoracic surgery or by other conditions. Fetal CT and CA may be lethal particularly in cases with fetal hydrops that sometimes benefit of intra-uterine instrumentation. After birth, symptoms are related to the amount of accumulated fluid. Sometimes, severe cardio-respiratory compromise prompts active therapy. Most patients with CT or CA benefit from observation, rest, and supportive measures alone. Drainage of the fluid may be necessary, but then loss of protein, fat, and lymphoid cells introduce new risks and require careful replacement. Low-fat diets with MCT and parenteral nutrition decrease fluid production while allowing adequate nutritional input. If lymph leakage does not stop, secretion inhibitors like somatostatin or octreotide are prescribed, although there is only weak evidence of their benefits. Imaging of the lymphatic system is indicated when the leaks persist, but this is technically demanding in children. Shunting of the lymph from one body space to another by means of valved catheters, embolization of the thoracic duct, and/or ligation of the major lymphatics may occasionally be indicated in cases refractory to all other treatments.


Assuntos
Quilotórax , Ascite Quilosa , Doenças do Recém-Nascido , Quilotórax/diagnóstico , Quilotórax/dietoterapia , Quilotórax/tratamento farmacológico , Quilotórax/cirurgia , Ascite Quilosa/diagnóstico , Ascite Quilosa/dietoterapia , Ascite Quilosa/tratamento farmacológico , Ascite Quilosa/cirurgia , Humanos , Recém-Nascido , Doenças do Recém-Nascido/diagnóstico , Doenças do Recém-Nascido/dietoterapia , Doenças do Recém-Nascido/tratamento farmacológico , Doenças do Recém-Nascido/cirurgia
18.
Pediatr Dermatol ; 30(3): 374-8, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22823281

RESUMO

Gorham-Stout syndrome is a rare disease characterized by progressive osteolysis leading to disappearance of the bone. Vascular proliferations have been implicated in the pathogenesis of this syndrome. The case of a 7-year-old girl with a prominent invasive lymphatic malformation on the lumbosacral area and massive osteolysis of the pelvic girdle is reported.


Assuntos
Região Lombossacral/anormalidades , Anormalidades Linfáticas/patologia , Osteólise Essencial/patologia , Ossos Pélvicos/anormalidades , Pele/patologia , Criança , Feminino , Humanos , Região Lombossacral/patologia , Osteólise Essencial/diagnóstico por imagem , Ossos Pélvicos/diagnóstico por imagem , Tomografia Computadorizada por Raios X
19.
Lymphat Res Biol ; 10(4): 164-72, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23215742

RESUMO

BACKGROUND: Progressive osteolysis caused by lympathic malformations is a rare condition that should be known by specialists involved in the study of lymphatic disorders because they are necessarily involved in the treatment. The purpose of the present study is to report on a large series of patients to illustrate the multiple clinical pictures and the wide range of therapeutic measures necessary for arresting bone destruction and lymphatic leak. METHODS AND RESULTS: Inclusion criteria were osteolysis associated with lymphatic malformation that required treatment. Diagnosis was based on history, plain X-rays, MRI, and demonstration of the lymphatic nature of the lesions with D2-40 immunohistochemistry. Treatment was based on resection of the bone lytic lesion or soft tissue lymphatic masses, control of chylothorax or chyloperitoneum, interferon, zoledronic acid, and radiotherapy. The study included 54 patients (25 females and 29 males) with a median age of 9 years (range 2 to 65). Eight patients had focal osteolysis without soft tissue lymphatic anomaly, 15 multifocal osteolysis without soft tissue lymphatic anomaly, 7 focal osteolysis associated with soft tissue lymphatic anomaly, and 24 multifocal osteolysis with soft tissue lymphatic anomaly. Among the wide variety of pharmacological therapies provided, only one protocol showed a consistent positive effect (end of ostelytic progression) in 17 patients who received a course of 6 to 15 months of interferon alpha-2B at 1.5 million units/m(2) body surface area/day in association with zoledronic acid at 0.05 mg/kg/month. Thirty-two patients underwent multiple surgical procedures in order to remove the soft tissue involved, correct orthopedic problems, or improve chylothorax, and three were treated with radiotherapy which was successful in one case. CONCLUSIONS: Osteolysis from lymphatic origin is a devastating surgical condition. Therapeutic options have to be considered separately if the disease is active or inactive and according to the targeted organ (skin, bone, or viscera). Total removal of the lymphatic anomaly is rarely possible, but its subtotal excision together with pharmacological antiangiogenic therapy in selected patients under surveillance of a multidisciplinary group familiarized with the disease, minimize the progression of both, lymphatic invasion, osteolysis, and their serious complications.


Assuntos
Anormalidades Linfáticas/complicações , Osteólise/diagnóstico , Osteólise/terapia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteólise/complicações
20.
J Cachexia Sarcopenia Muscle ; 3(3): 199-211, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22476919

RESUMO

BACKGROUND: Burn injury results in a chronic inflammatory, hypermetabolic, and hypercatabolic state persisting long after initial injury and wound healing. Burn survivors experience a profound and prolonged loss of lean body mass, fat mass, and bone mineral density, associated with significant morbidity and reduced quality of life. Understanding the mechanisms responsible is essential for developing therapies. A complete characterization of the pathophysiology of burn cachexia in a reproducible mouse model was lacking. METHODS: Young adult (12-16 weeks of age) male C57BL/6J mice were given full thickness burns using heated brass plates or sham injury. Food and water intake, organ and muscle weights, and muscle fiber diameters were measured. Body composition was determined by Piximus. Plasma analyte levels were determined by bead array assay. RESULTS: Survival and weight loss were dependent upon burn size. The body weight nadir in burned mice was 14 days, at which time we observed reductions in total body mass, lean carcass mass, individual muscle weights, and muscle fiber cross-sectional area. Muscle loss was associated with increased expression of the muscle ubiquitin ligase, MuRF1. Burned mice also exhibited reduced fat mass and bone mineral density, concomitant with increased liver, spleen, and heart mass. Recovery of initial body weight occurred at 35 days; however, burned mice exhibited hyperphagia and polydipsia out to 80 days. Burned mice had significant increases in serum cytokine, chemokine, and acute phase proteins, consistent with findings in human burn subjects. CONCLUSIONS: This study describes a mouse model that largely mimics human pathophysiology following severe burn injury. These baseline data provide a framework for mouse-based pharmacological and genetic investigation of burn-injury-associated cachexia.

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