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1.
RSC Pharm ; 1(2): 272-282, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38899150

RESUMO

Mitonafide-loaded liposomes are a promising strategy to overcome the neurotoxicity observed in clinical trials for this drug. This study investigates the influence of loaded mitonafide or a dimer analogue on different liposomal formulations and their therapeutic efficacy in vitro. Physicochemical properties of the liposomes were manipulated using different loading methods (namely bilayer or core loading) and varying the rigidity of the bilayer using distinct phospholipid compositions. Our results demonstrated that the mitonafide dimer analogue had a comparable encapsulation efficiency (EE%) into the liposomes when loaded into rigid or flexible bilayers in contrast to the low mitonafide monomer EE%. A pH gradient core loading method resulted in a more efficient mechanism to load the monomer into the liposomes. DOSY NMR and spectrofluorometric studies revealed key differences in the structure of the vesicles and the arrangement of the monomer or the dimer in the bilayer or the core of the liposomes. The in vitro assessment of the formulations using MDA-MB-231 and RT-112 cells revealed that a flexible lipid bilayer allows a faster drug release, which correlated well with the spectroscopy studies. This study investigated for the first time that the characteristics of the lipid bilayer and the loading method influence the encapsulation efficacy, colloidal properties, photoactivity and stability of mono and bis-naphthalimides loaded in a liposomal carrier, essential factors that will impact the performance of the formulation in a biological scenario.

2.
J Colloid Interface Sci ; 670: 585-598, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38776693

RESUMO

Whilst the development of advanced organic dots with aggregation-induced emission characteristics (AIE-dots) is being intensively studied, their clinical translation in efficient biotherapeutic devices has yet to be tackled. This study explores the synergistic interplay of oligo(styryl)benzenes (OSBs), potent fluorogens with an increased emission in the aggregate state, and Indocyanine green (ICG) as dual Near Infrared (NIR)-visible fluorescent nanovesicles with efficient reactive oxygen species (ROS) generation capacity for cancer treatment using photodynamic therapy (PDT). The co-loading of OSBs and ICG in different nanovesicles has been thoroughly investigated. The nanovesicles' physicochemical properties were manipulated via molecular engineering by modifying the structural properties of the lipid bilayer and the number of oligo(ethyleneoxide) chains in the OSB structure. Diffusion Ordered Spectroscopy (DOSY) NMR and spectrofluorometric studies revealed key differences in the structure of the vesicles and the arrangement of the OSB and ICG in the bilayer. The in vitro assessment of these OSB-ICG nanovesicles revealed that the formulations can increase the temperature and generate ROS after photoirradiation, showing for the first time their potential as dual photothermal/photodynamic (PTT/PDT) agents in the treatment of prostate cancer. Our study provides an exciting opportunity to extend the range of applications of OSB derivates to potentiate the toxicity of phototherapy in prostate and other types of cancer.


Assuntos
Lipossomos , Fotoquimioterapia , Neoplasias da Próstata , Espécies Reativas de Oxigênio , Masculino , Humanos , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/terapia , Lipossomos/química , Espécies Reativas de Oxigênio/metabolismo , Verde de Indocianina/química , Verde de Indocianina/farmacologia , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Tamanho da Partícula , Corantes Fluorescentes/química , Corantes Fluorescentes/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Derivados de Benzeno/química , Derivados de Benzeno/farmacologia , Imagem Óptica , Pontos Quânticos/química , Propriedades de Superfície , Estrutura Molecular
3.
Int J Mol Sci ; 25(1)2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38203286

RESUMO

Black phosphorus (BP) is one of the most promising nanomaterials for cancer therapy. This 2D material is biocompatible and has strong photocatalytic activity, making it a powerful photosensitiser for combined NIR photothermal and photodynamic therapies. However, the fast degradation of BP in oxic conditions (including biological environments) still limits its use in cancer therapy. This work proposes a facile strategy to produce stable and highly concentrated BP suspensions using lysolipid temperature-sensitive liposomes (LTSLs). This approach also allows for co-encapsulating BP nanoflakes and doxorubicin, a potent chemotherapeutic drug. Finally, we demonstrate that our BP/doxorubicin formulation shows per se high antiproliferative action against an in vitro prostate cancer model and that the anticancer activity can be enhanced through NIR irradiance.


Assuntos
Lipossomos , Neoplasias da Próstata , Masculino , Humanos , Temperatura , Neoplasias da Próstata/tratamento farmacológico , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Fósforo
4.
Hand (N Y) ; 17(6): NP11-NP15, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35321587

RESUMO

Giant cell tumor (GCT) is a benign, locally aggressive neoplasm with little incidence at the carpal bone level. We present a case of pyramidal bone GCT that required open biopsy for diagnosis. As a definitive treatment, en bloc resection of the pyramidal bone and luno-capitate arthrodesis were performed to avoid frequent relapses of these neoplasms and ensure proper functionality of the anatomical segment.


Assuntos
Neoplasias Ósseas , Tumor de Células Gigantes do Osso , Piramidal , Humanos , Tumor de Células Gigantes do Osso/diagnóstico por imagem , Tumor de Células Gigantes do Osso/cirurgia , Neoplasias Ósseas/cirurgia , Neoplasias Ósseas/patologia , Resultado do Tratamento , Recidiva Local de Neoplasia , Piramidal/diagnóstico por imagem , Piramidal/cirurgia
5.
Int J Pharm ; 607: 121018, 2021 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-34416329

RESUMO

In this study, novel cupric-tirapazamine [Cu(TPZ)2]-liposomes were developed as an effective hypoxia-targeted therapeutic, which potentiated radiotherapy in a three dimensional (3D) prostate cancer (PCa) model. To overcome the low water solubility of the Cu(TPZ)2, a remote loading method was developed to efficiently load the lipophilic complex into different liposomal formulations. The effect of pH, temperature, PEGylation, lipid composition, liposome size, lipid: complex ratio on the liposome properties, and drug loading was evaluated. The highest loading efficiency was obtained at neutral pH, which was independent of lipid composition and incubation time. In addition, enhanced drug loading was achieved upon decreasing the lipid:complex molar ratio with minimal effects on liposomes' morphology. Interestingly, the in vitro potency of the developed liposomes was easily manipulated by changing the lipid composition. The hydrophilic nature of our liposomal formulations improved the complex's solubility, leading to enhanced cellular uptake and toxicity, both in PCa monolayers and tumour spheroids. Moreover, Cu(TPZ)2-loaded liposomes combined with radiation, showed a significant reduction in PCa spheroids growth rate, compared to the free complex or radiation alone, which could potentiate radiotherapy in patients with localised advanced PCa.


Assuntos
Lipossomos , Neoplasias da Próstata , Humanos , Hipóxia , Masculino , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/radioterapia , Solubilidade , Tirapazamina
6.
Acta Biomater ; 134: 559-575, 2021 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-34274531

RESUMO

Prostate cancer (PC) is second-leading cancer in men, with limited treatment options available for men with advanced and metastatic PC. Prostate-specific antigen (PSA) and prostate-specific membrane antigen (PSMA) have been exploited as therapeutic targets in PC due to their upregulation in the advanced stages of the disease. To date, several PSA- and PSMA-activatable prodrugs have been developed to reduce the systemic toxicity of existing chemotherapeutics. Bioinspired nanovesicles have been exploited in drug delivery, offering prolonged drug blood circulation and higher tumour accumulation. For the first time, this study describes the engineering of dually targeted PSA/PSMA nanovesicles for advanced PC. PSMA-targeted bioinspired hybrids were prepared by hydrating a lipid film with anti-PSMA-U937 cell membranes and DOX-PSA prodrug, followed by extrusion. The bioinspired hybrids were characterised using dynamic light scattering, transmission electron microscopy, Dot blot, flow cytometry and Western blot. Cellular binding and toxicity studies in PC cancer cell lines were carried out using flow cytometry, confocal microscopy, and resazurin assay. Finally, tumour targeting and therapeutic efficacy studies were performed in solid and metastatic C4-2B-tumor-bearing mice. Interestingly, our PSMA-targeted hybrids demonstrated high cell uptake in PSMA-expressing cells with significant accumulation in solid and metastatic C4-2B tumour tissues following intravenous administration. More promisingly, our dually targeted PSA/PSMA hybrid significantly slowed down the C4-2B tumour growth in vivo, compared to free DOX-PSA and non-targeted PSA-hybrid. Our PSA/PSMA bioinspired hybrid could offer a highly selective treatment for advanced PC with lower side effects. STATEMENT OF SIGNIFICANCE: This study investigates a new approach to treat prostate cancer using dually targeted bioinspired nanovesicle . Our bioinspired vesicles are made mainly of a human blood cell membrane with a ligand recognising a specific marker (PSMA) on the surface of the prostate cancer cells. The present work describes the successful loading of a doxorubicin prodrug linked to a PSA- activatable peptide into these targeted bioinspired nanovesicle , where the active PSA enzyme presents in these cells converts the drug to its active form. Our dually targeted PSA/PSMA hybrid vesicles has successfully improved site-specific prodrug delivery to tackle advanced prostate cancer, offering a novel and effective prostate cancer treatment.


Assuntos
Pró-Fármacos , Neoplasias da Próstata , Animais , Humanos , Masculino , Camundongos , Antígeno Prostático Específico , Neoplasias da Próstata/tratamento farmacológico , Células U937
7.
J Control Release ; 332: 419-433, 2021 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-33677010

RESUMO

This study investigates the effect of PD1 blockade on the therapeutic efficacy of novel doxorubicin-loaded temperature-sensitive liposomes. Herein, we report photothermally-activated, low temperature-sensitive magnetoliposomes (mLTSL) for efficient drug delivery and magnetic resonance imaging (MRI). The mLTSL were prepared by embedding small nitrodopamine palmitate (NDPM)-coated iron oxide nanoparticles (IO NPs) in the lipid bilayer of low temperature-sensitive liposomes (LTSL), using lipid film hydration and extrusion. Doxorubicin (DOX)-loaded mLTSL were characterized using dynamic light scattering, differential scanning calorimetry, electron microscopy, spectrofluorimetry, and atomic absorption spectroscopy. Photothermal experiments using 808 nm laser irradiation were conducted. In vitro photothermal DOX release studies and cytotoxicity was assessed using flow cytometry and resazurin viability assay, respectively. In vivo DOX release and tumor accumulation of mLTSL(DOX) were assessed using fluorescence and MR imaging, respectively. Finally, the therapeutic efficacy of PD1 blockade in combination with photothermally-activated mLTSL(DOX) in CT26-tumor model was evaluated by monitoring tumor growth, cytokine release and immune cell infiltration in the tumor tissue. Interestingly, efficient photothermal heating was obtained by varying the IO NPs content and the laser power, where on-demand burst DOX release was achievable in vitro and in vivo. Moreover, our mLTSL exhibited promising MR imaging properties with high transverse r2 relaxivity (333 mM-1 s-1), resulting in superior MR imaging in vivo. Furthermore, mLTSL(DOX) therapeutic efficacy was potentiated in combination with anti-PD1 mAb, resulting in a significant reduction in CT26 tumor growth via immune cell activation. Our study highlights the potential of combining PD1 blockade with mLTSL(DOX), where the latter could facilitate chemo/photothermal therapy and MRI-guided drug delivery.


Assuntos
Doxorrubicina , Lipossomos , Linhagem Celular Tumoral , Sistemas de Liberação de Medicamentos , Imageamento por Ressonância Magnética , Fototerapia , Temperatura
8.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-33495138

RESUMO

INTRODUCTION AND OBJECTIVES: Osteoarticular tuberculosis, caused by a member of the Mycobacterium genus, represents approximately 10% of the total extrapulmonary tuberculosis in pediatric patients. Its low prevalence and nonspecific clinical presentation lead to a late diagnosis and elevated risk of sequelae. PATIENTS AND METHODS: This retrospective study included seven pediatric patients with non-vertebral osteoarticular tuberculosis diagnosed between 2006 and 2019. The patients were classified in accordance with the radiographic criteria of Kerri and Martini. RESULTS: The mean patient age was 7,4 years (median, 5 years; range, 2-16 years). The mean follow-up time was 18,5 months (range, 10-32 months). The mean diagnostic delay was 4,7 months (range, 1-8 months). The locations were femoral head osteoarthritis (two patients) and proximal humerus osteomyelitis, talus dome osteoarthritis, distal clavicle osteoarthritis, proximal ulna epiphysis osteoarthritis, and tibiotalar arthritis along with subtalar gland (one patient each). The clinical findings were lameness (four patients), localized pain (two patients), functional impotence, constitutional syndrome (asthenia, anorexia, and involuntary loss of>5% of total body weight) (two patients), local inflammatory signs (one patient), and fever (one patient). One patient was asymptomatic and received a diagnosis during pulmonary radiological analysis. Medical treatment with four drugs was performed in all patients; five patients required surgical treatment for abscess drainage, three of them open drainage, and two with laparoscopic drainage. CONCLUSIONS: The final results were satisfactory, such that 71% of patients recovered joint balance but with radiological sequelae in 57,1% patients. Good prognosis, according to our results, depends on younger age and early diagnosis with early medical or surgical treatments.

9.
Nanoscale Adv ; 3(14): 4029-4036, 2021 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-36132840

RESUMO

Although graphene oxide (GO) is leading the way in the biomedical field of 2D materials, nanosized black phosphorus (NBP) has recently come to attention for use in this challenging field. A direct comparison between these two materials, in this context, has never been described. Therefore, in this mini-review, we will critically compare the applications of NBP and GO in cancer therapy. Material functionalisation, biodegradation by design, phototherapy and immunotherapy will be summarised. This work aims to inspire researchers in designing the next generation of safe NBP platforms for cancer treatment, taking advantage of the vast experience gained with GO.

10.
J Control Release ; 330: 101-110, 2021 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-33333118

RESUMO

The present work describes the engineering of anti-PSMA peptide-decorated exosome mimetics (EMs) targeting advanced prostate cancer (PC). The targeted EMs were produced from anti-PSMA peptide, WQPDTAHHWATL, expressing U937 monoblastic cells, followed by successive extrusion cycles. The engineered EMs were nanosized, produced at a high yield, and displayed the anti-PSMA peptide, exosomal markers and monocytes proteins on their surface. As anticipated, PSMA-EMs showed increased cellular internalization in PSMA positive PC cell lines (LNCaP and C4-2B), compared to unmodified EMs. Most importantly, higher tumour targeting was observed in solid C4-2B tumours, following intravenous administration, confirming their targeting ability in vivo. Overall, our study indicates that the engineered anti-PSMA peptide-targeted EMs can be a promising drug delivery system for advanced PC.


Assuntos
Exossomos , Neoplasias da Próstata , Animais , Antígenos de Superfície , Linhagem Celular Tumoral , Glutamato Carboxipeptidase II , Humanos , Masculino , Camundongos , Camundongos Nus , Antígeno Prostático Específico , Neoplasias da Próstata/tratamento farmacológico
11.
J Control Release ; 328: 665-678, 2020 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-32961247

RESUMO

Doxorubicin (DOX)-loaded lysolipid temperature-sensitive liposomes (LTSLs) are a promising stimuli-responsive drug delivery system that rapidly releases DOX in response to mild hyperthermia (HT). This study investigates the influence of loaded DOX crystals on the thermosensitivity of LTSLs and their therapeutic efficacy in vitro and in vivo. The properties of DOX crystals were manipulated using different remote loading methods (namely (NH4)2SO4, NH4-EDTA and MnSO4) and varying the lipid:DOX weight ratio during the loading step. Our results demonstrated that (NH4)2SO4 or NH4-EDTA remote loading methods had a comparable encapsulation efficiency (EE%) into LTSLs in contrast to the low DOX EE% obtained using the metal complexation method. Cryogenic transmission electron microscopy (cryo-TEM) revealed key differences in the nature of DOX crystals formed inside LTSLs based on the loading buffer or/and the lipid:DOX ratio used, resulting in different DOX release profiles in response to mild HT. The in vitro assessment of DOX release/uptake in CT26 and PC-3 cells revealed that the use of a high lipid:DOX ratio exhibited a fast and controlled release profile in combination with mild HT, which correlated well with their cytotoxicity studies. Similarly, in vivo DOX release, tumour growth inhibition and mice survival rates were influenced by the physicochemical properties of LTSLs payload. This study demonstrates, for the first time, that the characteristics of DOX crystals loaded into LTSLs, and their conformational rearrangement during HT, are important factors that impact the TSLs performance in vivo.


Assuntos
Hipertermia Induzida , Lipossomos , Animais , Antibióticos Antineoplásicos , Linhagem Celular Tumoral , Doxorrubicina , Camundongos , Temperatura
12.
Colloids Surf B Biointerfaces ; 194: 111185, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32574928

RESUMO

Prostate cancer is the second cause of cancer death in men worldwide. Docetaxel (DTX), an antimitotic drug, is widely used for the treatment of metastatic prostate cancer patients. Taxotere® is a commercial DTX formulation. It contains a polysorbate 80 surfactant to improve DTX aqueous solubility, which has been associated with hypersensitivity reactions in patients. Liposomes have been used as promising delivery systems for a range of hydrophobic drugs, such as DTX, offering improved drug water solubility and biocompatibility, without compromising its anticancer activity. Herein, DTX-loaded liposomes were developed using the Box-Behnken factorial design. The optimized formulation was nano-sized, homogenous in size (67.47 nm) with high DTX encapsulation efficiency (99.95 %). The encapsulated DTX was in a soluble amorphous state, which was slowly released. Next, to increase the liposomes selectivity to prostate cancer cells, cetuximab, an anti-EGFR monoclonal antibody. was successfully conjugated to the surface of liposomes, without compromising cetuximab protein structure and stability. As expected, our results showed higher cellular uptake and toxicity of immunoliposomes, compared to non-targeted liposomes, in DU145 (EGFR-overxpressing) prostate cancer cells. To the best of our knowledge, this is the first report of engineering EGFR-targeted liposomes to enhance the selectivity of DTX delivery to EGFR-positive prostate cancer cells.


Assuntos
Antineoplásicos , Neoplasias da Próstata , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Docetaxel , Sistemas de Liberação de Medicamentos , Receptores ErbB , Humanos , Lipossomos , Masculino , Neoplasias da Próstata/tratamento farmacológico
13.
J Vis Exp ; (157)2020 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-32202528

RESUMO

The presented protocol enables a high-throughput continuous preparation of low temperature-sensitive liposomes (LTSLs), which are capable of loading chemotherapeutic drugs, such as doxorubicin (DOX). To achieve this, an ethanolic lipid mixture and ammonium sulfate solution are injected into a staggered herringbone micromixer (SHM) microfluidic device. The solutions are rapidly mixed by the SHM, providing a homogeneous solvent environment for liposomes self-assembly. Collected liposomes are first annealed, then dialyzed to remove residual ethanol. An ammonium sulfate pH-gradient is established through buffer exchange of the external solution by using size exclusion chromatography. DOX is then remotely loaded into the liposomes with high encapsulation efficiency (> 80%). The liposomes obtained are homogenous in size with Z-average diameter of 100 nm. They are capable of temperature-triggered burst release of encapsulated DOX in the presence of mild hyperthermia (42 °C). Indocyanine green (ICG) can also be co-loaded into the liposomes for near-infrared laser-triggered DOX release. The microfluidic approach ensures high-throughput, reproducible and scalable preparation of LTSLs.


Assuntos
Química Farmacêutica/métodos , Doxorrubicina/administração & dosagem , Sistemas de Liberação de Medicamentos , Verde de Indocianina/administração & dosagem , Lipídeos/química , Lipossomos/química , Microfluídica , Sulfato de Amônio , Soluções Tampão , Cromatografia , Concentração de Íons de Hidrogênio , Dispositivos Lab-On-A-Chip , Temperatura
14.
Materials (Basel) ; 12(14)2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31295825

RESUMO

Superparamagnetic iron oxide nanoparticles are one of the most prominent agents used in theranostic applications, with MRI imaging the main application assessed. The biomolecular interface formed on the surface of a nanoparticle in a biological medium determines its behaviour in vitro and in vivo. In this study, we have compared the formation of the protein corona on highly monodisperse iron oxide nanoparticles with two different coatings, dimercaptosuccinic acid (DMSA), and after conjugation, with a bifunctional polyethylene glycol (PEG)-derived molecule (2000 Da) in the presence of Wistar rat plasma. The protein fingerprints around the nanoparticles were analysed in an extensive proteomic study. The results presented in this work indicate that the composition of the protein corona is very difficult to predict. Proteins from different functional categories-cell components, lipoproteins, complement, coagulation, immunoglobulins, enzymes and transport proteins-were identified in all samples with very small variability. Although both types of nanoparticles have similar amounts of bonded proteins, very slight differences in the composition of the corona might explain the variation observed in the uptake and biotransformation of these nanoparticles in Caco-2 and RAW 264.7 cells. Cytotoxicity was also studied using a standard 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay. Controlling nanoparticles' reactivity to the biological environment by deciding on its surface functionalization may suggest new routes in the control of the biodistribution, biodegradation and clearance of multifunctional nanomedicines.

15.
ACS Appl Mater Interfaces ; 11(8): 7695-7702, 2019 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-30693754

RESUMO

The last decade has seen an increase in the application of graphene oxide (GO) in the biomedical field. GO has been successfully exploited for its ability to deliver many kinds of drugs into target cells. However, GO toxicity assessment is still controversial. Several studies have demonstrated that GO protein coating is crucial to alleviate the material's toxicity. Besides, coronation leads to the formation of big agglomerates, reducing the cellular uptake of the material and thus its therapeutic efficiency. In this work, we propose a simple and efficient method based on rapid (ultra-turrax, UT) mixing to control protein corona formation. Using the UT protocol, we were able to reduce GO agglomeration in the presence of proteins and obtain stable GO dispersions in cell culture media. By labelling GO with luminescent nanoparticles (quantum dots), we studied the GO internalization kinetic and efficiency. Comparing the "classic" and UT protocols, we found that the latter allows faster and more efficient internalization both in macrophages and HeLa cells without affecting cell viability. We believe that the use of UT protocol will be interesting and suitable for the preparation of next-generation GO-based drug-delivery platforms.


Assuntos
Meios de Cultura/química , Grafite/química , Animais , Sobrevivência Celular/efeitos dos fármacos , Células HeLa , Humanos , Camundongos , Coroa de Proteína/química , Pontos Quânticos/química , Pontos Quânticos/toxicidade , Células RAW 264.7
18.
Endocrinol Nutr ; 58(1): 24-31, 2011 Jan.
Artigo em Espanhol | MEDLINE | ID: mdl-21277266

RESUMO

We present our experience with low-dose cinacalcet to normalize serum calcium in patients with primary hyperparathyroidism (PHPT) not eligible for surgery. We analyzed the impact of this drug on various parameters of calcium-phosphorus metabolism and its tolerability profile. We recruited 17 patients diagnosed with PHPT who had hypercalcemia and also met one or more of the following inclusion criteria: elevated risk for parathyroidectomy, persistent/recurrent PHPT after previous parathyroid surgery or refusal to undergo surgery. The starting dose of cinacalcet was 30 or 60 mg/day, which was adjusted depending on the degree of calcemia reduction and tolerance to the drug. We observed a reduction in serum calcium that was already evident in the first post-treatment test. Appropriate dose adjustment was performed when required and normal serum calcium levels were achieved in most patients, remaining stable during follow-up. Parathyroid hormone was reduced but not normalized in most patients. Calciuria decreased while serum phosphate and alkaline phosphatase levels increased. Cinacalcet tolerance was generally good at the doses used. The most common adverse effects were weakness, dizziness and asthenia, leading to treatment withdrawal in only one patient. We conclude that low-dose cinacalcet reduces serum calcium efficiently, normalizes calcium levels in most patients with PHPT not eligible for surgical treatment and has a good tolerability profile.


Assuntos
Cálcio/sangue , Hipercalcemia/tratamento farmacológico , Hiperparatireoidismo Primário/sangue , Naftalenos/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Fosfatase Alcalina/sangue , Astenia/induzido quimicamente , Cálcio/urina , Cinacalcete , Contraindicações , Relação Dose-Resposta a Droga , Fadiga/induzido quimicamente , Feminino , Humanos , Hipercalcemia/etiologia , Hiperparatireoidismo Primário/complicações , Masculino , Pessoa de Meia-Idade , Naftalenos/administração & dosagem , Naftalenos/efeitos adversos , Náusea/induzido quimicamente , Hormônio Paratireóideo/sangue , Paratireoidectomia , Fósforo/sangue , Estudos Prospectivos , Vitamina D/sangue
19.
Diabetes Technol Ther ; 11(9): 615-21, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19764842

RESUMO

OBJECTIVES: Anthropometric indices have been associated with insulin resistance in children. This study (1) determined the association between insulin resistance and anthropometric indices, including body mass index (BMI), waist circumference (WC), WC/height, weight/(sitting height)(2), and WC/sitting height, and (2) compared the abilities of these five indices to identify children with insulin resistance. METHODS: Data were collected from six elementary schools in Argentina between April and August 2007. Anthropometric data and Tanner staging were obtained. Fasting serum concentrations of glucose, lipids, and insulin were measured. RESULTS: Six hundred twenty-five children (318 boys) between 6 and 14 years old were examined. The mean age of the children was 9.6 +/- 2.0 years. Ninety-six (15.4%) of the children were obese, 91 (14.6%) were overweight, and 438 (70.1%) were normal weight using Centers for Disease Control and Prevention norms. Sixty percent, 23.0%, 14.0%, and 3.0% were Tanner stage I, II, III, and IV, respectively. The areas under the receiver operator characteristic curves were as follows: WC = 0.78 +/- 0.021 (95% confidence interval [CI] 0.74-0.82), BMI = 0.77 +/- 0.022 (95% CI 0.73-0.82), weight/(sitting height)(2) = 0.76 +/- 0.022 (95% CI 0.72-0.81), WC/height = 0.67 +/- 0.027 (95% CI 0.62-0.72), and WC/sitting height = 0.67 +/- 0.27 (95% CI 0.62-0.72), indicating that BMI, WC, and weight/(sitting height)(2) were acceptable predictors for insulin resistance, whereas WC/height and WC/sitting height were fair predictors as the areas under the curve were <0.7. CONCLUSIONS: This study suggests that WC and BMI are (and remain) the best correlates for insulin resistance. In contrast, the indices of the ratio between WC and height were fair predictors for insulin resistance. Additional longitudinal studies should be done to further confirm these findings.


Assuntos
Antropometria/métodos , Índice de Massa Corporal , Intolerância à Glucose/diagnóstico , Resistência à Insulina , Circunferência da Cintura , Adolescente , Envelhecimento , Algoritmos , Argentina/epidemiologia , Glicemia/análise , Estatura , Criança , Feminino , Intolerância à Glucose/epidemiologia , Humanos , Insulina/sangue , Lipídeos/sangue , Masculino , Sobrepeso/epidemiologia , Prevalência , Puberdade , Fatores Sexuais , Fatores Socioeconômicos , Estatística como Assunto
20.
Electrophoresis ; 29(11): 2363-71, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18449861

RESUMO

The reverse staining, with imidazole-SDS-zinc, of PEG-linked proteins separated by SDS-PAGE was studied. Using model conjugates (interferon-alpha 2b (IFN-alpha2b) reacted with either a branched-chain (40,000) PEG (PEG2,40) or a linear monomethoxy PEG polymer (Mr of 12,000) and chromatographically purified monoPEG2,40-IFN-alpha2b), conventional small-format analytical gels (<1 mm thick) showed typical detection patterns (i.e., transparent, colorless bands clearly discernible against a zinc imidazolate-generated white gel background), in less than 20 min. Nonreacted (free) PEG was almost undetected, as expected. The reverse-stained PEGylated IFN-alpha2b patterns were qualitatively indistinguishable from those of parallel gels stained with iodine (I2). The LOD was estimated in the low nanogram range (e.g., at about 7 ng for mono- or bi-PEG2,40 IFN-alpha2b per lane on gradient (4-17%) gels). Also, this stain allowed the visualization of Coomassie blue-undetected PEG-IFN bands, and could be restained with I2. PEGylated species of lysozyme, a low-molecular-weight peptide, ovalbumin, and chymotrypsin were used to demonstrate the generality of this stain. We also show (i) how to counteract the adverse effect of some parameters (e.g., gel thickness above 1 mm, long gel length, low (e.g., 4-6%) acrylamide concentration) on the reverse staining process and (ii) that the properties of the reverse-stained PEGylated proteins remain unchanged, as judged by analyzing both the ion exchange chromatography-based positional isomer separation profile and enzyme-linked immunosorbent response of PEG-IFN recovered from gels. Consequently, this technique may be useful for the rapid analysis or the small-scale preparation of PEGylated proteins.


Assuntos
Eletroforese em Gel de Poliacrilamida/métodos , Imidazóis/química , Interferon-alfa/análise , Polietilenoglicóis/química , Proteínas/análise , Coloração e Rotulagem/métodos , Zinco/química , Interferon alfa-2 , Proteínas Recombinantes , Sensibilidade e Especificidade
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