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1.
J Biochem Mol Toxicol ; 37(5): e23322, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36799065

RESUMO

Mammalian target of Rapamycin C1 (mTORC1) inhibition limits plaque progression in atherosclerosis. The present study evaluated the protective effect of sulfamethizole on poloxamer 407-induced atherosclerotic neointima formation in C57BL/6 mice via mTOR inhibition. Poloxamer 407 (P-407) (0.5 g/kg body weight) was administered intraperitoneally to male C57BL/6 mice every third day for 148 days to induce chronic hyperlipidemia. From Day 121 to 148, animals were additionally administered Sulfamethizole (5, 10, and 50 mg/kg, p.o.), Rapamycin (0.5 mg/kg, positive control), or vehicle (1 ml/kg). Plasma lipid levels were measured on Days 120 and 148. Upon sacrifice, histological studies were performed, and aortic tissue interleukin (IL)-6, tumor necrosis factor-α (TNF-α), and mTOR levels were evaluated. A molecular docking study was carried out to mimic the interaction of sulfamethizole with mTOR protein. Chronic P-407 administration significantly (p < 0.001) elevated plasma lipid levels, compared with those of the normal control group. Chronic hyperlipidemia resulted in increased tunica intima thickness, collagen deposition, and IL-6, TNF-α, and mTOR levels. Treatment with Sulfamethizole attenuated these parameters significantly in a dose-dependent manner. Molecular docking studies showed a significant interaction of Sulfamethizole with mTOR. In conclusion, this study suggests that sulfamethizole significantly limits poloxamer 407-induced atherosclerotic neointima formation in C57BL/6 mice via mTOR inhibition.


Assuntos
Aterosclerose , Neointima , Poloxâmero , Sulfametizol , Animais , Masculino , Camundongos , Aterosclerose/metabolismo , Lipídeos , Camundongos Endogâmicos C57BL , Simulação de Acoplamento Molecular , Neointima/induzido quimicamente , Poloxâmero/efeitos adversos , Sulfametizol/uso terapêutico , Serina-Treonina Quinases TOR/metabolismo , Fator de Necrose Tumoral alfa
2.
JAMA ; 325(15): 1513-1523, 2021 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-33877274

RESUMO

Importance: Although effective agents are available to prevent painful vaso-occlusive episodes of sickle cell disease (SCD), there are no disease-modifying therapies for ongoing painful vaso-occlusive episodes; treatment remains supportive. A previous phase 3 trial of poloxamer 188 reported shortened duration of painful vaso-occlusive episodes in SCD, particularly in children and participants treated with hydroxyurea. Objective: To reassess the efficacy of poloxamer 188 for vaso-occlusive episodes. Design, Setting, and Participants: Phase 3, randomized, double-blind, placebo-controlled, multicenter, international trial conducted from May 2013 to February 2016 that included 66 hospitals in 12 countries and 60 cities; 388 individuals with SCD (hemoglobin SS, SC, S-ß0 thalassemia, or S-ß+ thalassemia disease) aged 4 to 65 years with acute moderate to severe pain typical of painful vaso-occlusive episodes requiring hospitalization were included. Interventions: A 1-hour 100-mg/kg loading dose of poloxamer 188 intravenously followed by a 12-hour to 48-hour 30-mg/kg/h continuous infusion (n = 194) or placebo (n = 194). Main Outcomes and Measures: Time in hours from randomization to the last dose of parenteral opioids among all participants and among those younger than 16 years as a separate subgroup. Results: Of 437 participants assessed for eligibility, 388 were randomized (mean age, 15.2 years; 176 [45.4%] female), the primary outcome was available for 384 (99.0%), 15-day follow-up contacts were available for 357 (92.0%), and 30-day follow-up contacts were available for 368 (94.8%). There was no significant difference between the groups for the mean time to last dose of parenteral opioids (81.8 h for the poloxamer 188 group vs 77.8 h for the placebo group; difference, 4.0 h [95% CI, -7.8 to 15.7]; geometric mean ratio, 1.2 [95% CI, 1.0-1.5]; P = .09). Based on a significant interaction of age and treatment (P = .01), there was a treatment difference in time from randomization to last administration of parenteral opioids for participants younger than 16 years (88.7 h in the poloxamer 188 group vs 71.9 h in the placebo group; difference, 16.8 h [95% CI, 1.7-32.0]; geometric mean ratio, 1.4 [95% CI, 1.1-1.8]; P = .008). Adverse events that were more common in the poloxamer 188 group than the placebo group included hyperbilirubinemia (12.7% vs 5.2%); those more common in the placebo group included hypoxia (12.0% vs 5.3%). Conclusions and Relevance: Among children and adults with SCD, poloxamer 188 did not significantly shorten time to last dose of parenteral opioids during vaso-occlusive episodes. These findings do not support the use of poloxamer 188 for vaso-occlusive episodes. Trial Registration: ClinicalTrials.gov Identifier: NCT01737814.


Assuntos
Anemia Falciforme/tratamento farmacológico , Dor/tratamento farmacológico , Poloxâmero/uso terapêutico , Vasodilatadores/uso terapêutico , Adolescente , Adulto , Analgésicos Opioides/uso terapêutico , Anemia Falciforme/complicações , Criança , Método Duplo-Cego , Feminino , Humanos , Masculino , Dor/etiologia , Placebos/efeitos adversos , Placebos/uso terapêutico , Poloxâmero/efeitos adversos , Vasodilatadores/efeitos adversos , Adulto Jovem
3.
Br J Cancer ; 123(3): 369-377, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32457364

RESUMO

BACKGROUND: Minimally invasive intratumoural administration of thermoresponsive hydrogels, that transition from liquid to gel in response to temperature, has been proposed as a potential treatment modality for solid tumours. The aim of this study was to assess the inherent cytotoxicity of a poloxamer-based thermoresponsive hydrogel in a murine xenograft model of lung cancer. METHODS: In vitro viability assessment was carried out in a lung cancer (A549) and non-cancerous (Balb/c 3T3 clone A31) cell line. Following intratumoural administration of saline or the thermoresponsive hydrogel to an A549 xenograft model in female Athymic Nude-Foxn1nu mice (n = 6/group), localisation was confirmed using IVIS imaging. Tumour volume was assessed using callipers measurements over 14 days. Blood serum was analysed for liver and kidney damage and ex vivo tissue samples were histologically assessed. RESULTS: The thermoresponsive hydrogel demonstrated a dose-dependent cancer cell-specific toxicity in vitro and was retained in situ for at least 14 days in the xenograft model. Tumour volume increase was statistically significantly lower than saline treated control at day 14 (n = 6, p = 0.0001), with no associated damage of hepatic or renal tissue observed. CONCLUSIONS: Presented is a poloxamer-based thermoresponsive hydrogel, suitable for intratumoural administration and retention, which has demonstrated preliminary evidence of local tumour control, with minimal off-site toxicity.


Assuntos
Hidrogéis/administração & dosagem , Neoplasias Pulmonares/terapia , Poloxâmero/administração & dosagem , Células A549 , Técnicas de Ablação , Animais , Células 3T3 BALB , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Humanos , Hidrogéis/efeitos adversos , Hidrogéis/farmacocinética , Neoplasias Pulmonares/sangue , Camundongos , Poloxâmero/efeitos adversos , Poloxâmero/farmacocinética , Termodinâmica , Resultado do Tratamento , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Toxicol Pathol ; 46(1): 85-100, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29096596

RESUMO

To investigate the effects of common nanosuspension-stabilizing excipients on the nature and temporal evolution of histopathological changes at intramuscular (i.m.) administration sites, 5 groups of 39 male rats per group received a single injection of 1 of the 5 analogous crystalline drug nanosuspensions containing 200 mg/ml of an antiviral compound with particle sizes of ±200 nm and identical vehicle compositions, except for the type of nanosuspension stabilizer. The investigated stabilizers were poloxamer 338, poloxamer 407, d-α-tocopherol polyethylene glycol 1,000-succinate (TPGS), polysorbate 80, and polysorbate 80 combined with egg phosphatidylglycerol. Histopathology and immunohistochemistry revealed progressive inflammatory changes at the i.m. administration sites and the draining lymph nodes that differed according to the time point of sacrifice and the type of stabilizer. Although the overall time course of inflammatory changes was similar across the groups, differences in the nature, severity, and timing of the inflammatory response were observed between animals injected with poloxamer- or TPGS-containing nanosuspensions and those injected with formulations containing polysorbate 80. A more severe and prolonged active inflammatory phase, the presence of multinucleate giant cells, prolonged macrophage infiltration of the formulation depot, and more persistent histiocytic infiltrates in the lymph nodes were observed in the polysorbate 80-containing nanosuspension groups. Such vehicle-mediated effects could influence the overall tolerability profile of long-acting nanosuspensions.


Assuntos
Antivirais/química , Excipientes/efeitos adversos , Nanopartículas/administração & dosagem , Animais , Antivirais/administração & dosagem , Injeções Intramusculares , Masculino , Poloxâmero/efeitos adversos , Polissorbatos/efeitos adversos , Ratos , Ratos Sprague-Dawley , Vitamina E/efeitos adversos
5.
Pharm Dev Technol ; 22(3): 336-349, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28240141

RESUMO

CONTEXT: Nanostructured lipid carrier (NLC) dispersions present low viscosity and poor mucoadhesive properties, which reduce the pre-corneal residence time and consequently, the bioavailability of ocular drugs. OBJECTIVE: The aim of this study was to prepare thermoresponsive eyedrops based on the combination of lipid nanoparticles and a thermoresponsive polymer with mucomimetic properties (Pluronic® F-127). MATERIALS AND METHODS: NLCi dispersions were prepared based on the melt-emulsification and ultrasonication technique. Physicochemical and morphological characteristics of the colloidal dispersions were evaluated. The formulation was also investigated for potential cytotoxicity in Y-79 human retinoblastoma cells and the in vitro drug release profile of the ibuprofen was determined. RESULTS: NLCi showed a Z-average below 200 nm, a highly positive zeta potential and an efficiency of encapsulation (EE) of ∼90%. The gelification of the NLCi dispersion with 15% (w/w) Pluronic® F-127 did not cause significant changes to the physicochemical properties. The potential NLC-induced cytotoxicity was evaluated by the Alamar Blue reduction assay in Y-79 cells, and no relevant cytotoxicity was observed after exposure to 0-100 µg/mL NLC for up to 72 hours. The optimized formulations showed a sustained release of ibuprofen over several hours. DISCUSSION AND CONCLUSION: The strategy proposed in this work can be successfully used to increase the bioavailability and the therapeutic efficacy of conventional eyedrops.


Assuntos
Anti-Inflamatórios não Esteroides/administração & dosagem , Portadores de Fármacos/química , Composição de Medicamentos/métodos , Ibuprofeno/administração & dosagem , Lipídeos/química , Nanoestruturas/química , Poloxâmero/química , Anti-Inflamatórios não Esteroides/efeitos adversos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Preparações de Ação Retardada , Portadores de Fármacos/efeitos adversos , Liberação Controlada de Fármacos , Estabilidade de Medicamentos , Humanos , Ibuprofeno/efeitos adversos , Lipídeos/efeitos adversos , Lubrificantes Oftálmicos , Nanoestruturas/efeitos adversos , Soluções Oftálmicas , Poloxâmero/efeitos adversos , Reologia , Propriedades de Superfície , Viscosidade
6.
Ann Otol Rhinol Laryngol ; 125(2): 105-14, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26296929

RESUMO

OBJECTIVE: This exploratory clinical trial evaluated the safety and clinical activity of a novel, sustained-exposure formulation of ciprofloxacin microparticulates in poloxamer (OTO-201) administered during tympanostomy tube placement in children. METHODS: Double-blind, randomized, prospective, placebo- and sham-controlled, multicenter Phase 1b trial in children (6 months to 12 years) with bilateral middle ear effusion requiring tympanostomy tube placement. Patients were randomized to intraoperative OTO-201 (4 mg or 12 mg), placebo, or sham (2:1:1 ratio). RESULTS: Eighty-three patients (52 male/31 female; mean age, 2.80 years) were followed for safety (otoscopic exams, cultures, audiometry, and tympanometry) and clinical activity, defined as treatment failure (physician-documented otorrhea and/or otic or systemic antibiotic use ≥3 days post surgery). At baseline, 14.3% to 36.8% of children showed positive cultures of middle ear effusion samples in at least 1 ear. Through day 15, treatment failures accounted for 14.3%, 15.8%, 45.5%, and 42.9% of patients (OTO-201 4 mg, OTO-201 12 mg, placebo, and sham, respectively); treatment failure reductions for OTO-201 doses were significant compared to pooled control (P values = .023 and .043, respectively). Observed OTO-201 safety profile was indistinguishable from placebo or sham. CONCLUSIONS: Results of this first clinical trial suggest that OTO-201 was well tolerated and shows preliminary clinical activity in treating tympanostomy tube otorrhea.


Assuntos
Ciprofloxacina , Cuidados Intraoperatórios/métodos , Ventilação da Orelha Média/métodos , Otite Média com Derrame , Poloxâmero , Antibacterianos/administração & dosagem , Antibacterianos/farmacocinética , Criança , Pré-Escolar , Ciprofloxacina/administração & dosagem , Ciprofloxacina/farmacocinética , Preparações de Ação Retardada , Relação Dose-Resposta a Droga , Método Duplo-Cego , Monitoramento de Medicamentos/métodos , Excipientes/administração & dosagem , Excipientes/efeitos adversos , Feminino , Humanos , Lactente , Injeção Intratimpânica , Masculino , Otite Média com Derrame/diagnóstico , Otite Média com Derrame/microbiologia , Otite Média com Derrame/cirurgia , Poloxâmero/administração & dosagem , Poloxâmero/efeitos adversos , Poloxâmero/farmacologia , Resultado do Tratamento
7.
J Antimicrob Chemother ; 69(12): 3282-93, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25139839

RESUMO

OBJECTIVES: Over-the-counter access to an inexpensive, effective topical microbicide could reduce the transmission of HIV and would increase women's control over their health and eliminate the need to obtain their partners' consent for prophylaxis. Chronic infection with herpes simplex virus 2 (HSV-2), also known as human herpes virus 2, has been shown to facilitate HIV infection and speed the progression to immunodeficiency disease. Our objective is to develop a drug formulation that protects against both HSV-2 and HIV infection and adheres to the vaginal surface with extended residence time. METHODS: We developed a formulation using two approved antiviral active pharmaceutical ingredients, aciclovir and tenofovir, in a novel bioadhesive vaginal delivery platform (designated SR-2P) composed of two polymers, poloxamer 407 NF (Pluronic(®) F-127) and polycarbophil USP (Noveon(®) AA-1). The efficacy of the formulation to protect from HSV-2 infection was tested in vitro and in vivo. In addition to its efficacy, it is essential for a successful microbicide to be non-irritating to the vaginal mucosa. We therefore tested our SR-2P platform gel in the FDA gold-standard microbicide safety model in rabbits and also in a rat vaginal irritation model. RESULTS: Our studies indicated that SR-2P containing 1% aciclovir and 5% tenofovir protects (i) Vero cells from HSV-2 infection in vitro and (ii) mice from HSV-2 infection in vivo. Our results further demonstrated that SR-2P was not irritating in either vaginal irritation model. CONCLUSIONS: We conclude that SR-2P containing aciclovir and tenofovir may be a suitable candidate microbicide to protect humans from vaginal HSV-2 infection.


Assuntos
Aciclovir/administração & dosagem , Adenina/análogos & derivados , Anti-Infecciosos/administração & dosagem , Herpes Genital/prevenção & controle , Herpesvirus Humano 2/efeitos dos fármacos , Organofosfonatos/administração & dosagem , Cremes, Espumas e Géis Vaginais/administração & dosagem , Resinas Acrílicas/administração & dosagem , Resinas Acrílicas/efeitos adversos , Aciclovir/efeitos adversos , Adenina/administração & dosagem , Adenina/efeitos adversos , Animais , Anti-Infecciosos/efeitos adversos , Chlorocebus aethiops , Modelos Animais de Doenças , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/patologia , Feminino , Camundongos Endogâmicos BALB C , Organofosfonatos/efeitos adversos , Poloxâmero/administração & dosagem , Poloxâmero/efeitos adversos , Coelhos , Ratos Sprague-Dawley , Tenofovir , Resultado do Tratamento , Cremes, Espumas e Géis Vaginais/efeitos adversos , Células Vero
8.
Mil Med ; 189(Suppl 3): 99-105, 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-39160800

RESUMO

INTRODUCTION: Definitive management of non-compressible intra-abdominal hemorrhage (NCIAH) currently requires a surgeon and operating room capable of performing damage control surgery. In a wartime scenario or a geographically remote environment, these may not be readily available. In this study, we sought to test the safety of 2 emerging injectable hemostatic agents (CounterFlow and Fast Onset Abdominal Management, or FOAM, poloxamer component) versus normal saline control over a prolonged monitoring duration following administration by a non-surgical provider. MATERIALS AND METHODS: The Institutional Animal Care and Use Committee approved all research conducted in this study. We randomized male New Zealand white rabbits into 2 monitoring cohorts of 24 hours and 2 weeks. Each cohort contained 3 treatment groups (n = 4 rabbits/group): CounterFlow, the testable poloxamer component of FOAM, and normal saline control. We injected each treatment intraperitoneally in the left lower abdominal quadrant. Doses were 15 mL/kg for CounterFlow, 6.3 mL/kg for the poloxamer component of FOAM, and 15 mL/kg for normal saline. We conducted all injections under isoflurane anesthesia monitored by trained veterinary staff. Animals were euthanized at each cohort end point, and a veterinary pathologist blinded to treatment type performed necropsy. The primary outcome was incidence of intra-abdominal adhesions at necropsy. Quantitatively, adhesions when present were graded by the veterinary pathologist on a 1 to 4 scale, where "1" represented adhesions involving from 1 to 25% of the examined abdomen, "2" represented from 26 to 50%, "3" represented from 51 to 75%, and "4" represented from 76 to 100%. Qualitatively, adhesions present were graded by degree ("1" = minimal, "2" = mild, "3" = moderate, and "4" = severe) and chronicity ("1" = acute, "2" = subacute, and "3" = chronic). We also drew d-dimer blood values and measured body weights for each animal. Statistical analysis included either repeated measures 2-way ANOVA or a mixed-effects model (in the case of missing data) with Geisser-Greenhouse correction. We adjusted multiple comparisons using Tukey statistical hypothesis tests. RESULTS: In the 2-week cohort, 3 CounterFlow animals showed adhesions judged to be "1" quantitatively. Qualitatively, 2 of these were assessed as "1" for degree of adhesions and the other demonstrated a "2." On the chronicity of adhesions scale, 1 animal demonstrated a "2" and 2 demonstrated a "3." No animals in other groups (FOAM and control) demonstrated adhesions. CounterFlow-treated animals showed a statistically significant rise in d-dimer values in the 24-hour cohort only. In the 2-week cohort, CounterFlow-treated animals showed a decrease in body weight at 24 hours after injection but returned to their baseline (normal) body weights at 7 days. CONCLUSIONS: Findings from this study demonstrate that the tested ingredients of FOAM poloxamer component are safe for intraperitoneal injection and hold potential for further study directed toward prehospital non-compressible intra-abdominal hemorrhage management by non-surgical providers. Although CounterFlow produced abdominal adhesions in 3 of 4 rabbits in the 2-week cohort, these were determined to be "minimal" or "mild" in degree.


Assuntos
Hemostáticos , Animais , Coelhos , Aderências Teciduais , Masculino , Hemostáticos/administração & dosagem , Injeções Intraperitoneais , Poloxâmero/efeitos adversos , Poloxâmero/administração & dosagem , Incidência , Abdome/cirurgia
9.
Eur J Vasc Endovasc Surg ; 45(1): 44-5, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23158433

RESUMO

It is very difficult to identify whether the use of the thermosensitive polymer LeGoo offers advantages over the use of clamps or clampless techniques for infra-inguinal bypass. This issue of the journal provides much additional information about the use of LeGoo. We have summarised all the available evidence. In a very heterogeneous patient population, with heterogeneous graft type and location, the primary technical success rate remains high at 90% [95%CI 83-99], the 3 months secondary graft patency is 71 [95%CI 58-84]% and limb salvage is 78% [95%CI 68-89]%. These promising early results need to be followed by extended follow up of the patients and standardised outcome reporting in the future.


Assuntos
Perda Sanguínea Cirúrgica/prevenção & controle , Embolização Terapêutica/métodos , Doença Arterial Periférica/cirurgia , Poloxâmero/uso terapêutico , Enxerto Vascular , Temperatura Corporal , Constrição , Embolectomia , Embolia/etiologia , Embolia/fisiopatologia , Embolia/cirurgia , Embolização Terapêutica/efeitos adversos , Embolização Terapêutica/mortalidade , Oclusão de Enxerto Vascular/etiologia , Oclusão de Enxerto Vascular/fisiopatologia , Oclusão de Enxerto Vascular/cirurgia , Humanos , Salvamento de Membro , Doença Arterial Periférica/mortalidade , Doença Arterial Periférica/fisiopatologia , Poloxâmero/efeitos adversos , Poloxâmero/química , Reoperação , Resultado do Tratamento , Enxerto Vascular/efeitos adversos , Enxerto Vascular/mortalidade , Grau de Desobstrução Vascular
10.
Eur J Vasc Endovasc Surg ; 45(1): 51-6, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23134676

RESUMO

OBJECTIVE: The study aims to assess a novel thermosensitive polymer (LeGoo(®)) for distal vessel control during infra-popliteal (crural/pedal) bypass surgery in severe leg ischaemia. METHOD: Retrospective analysis of all distal bypasses from October 2009 to February 2012. Technical success, patency, limb salvage and amputation-free survival rates were analysed. RESULTS: Fifty-four infra-popliteal bypasses using the polymer were performed in 46 patients. The distal anastomosis was at the anterior tibial (n = 15, 28%), posterior tibial (n = 12, 22%), peroneal (n = 8, 15%), tibio-peroneal trunk (n = 8, 15%) and dorsalis pedis arteries (n = 11, 20%). Technical success was achieved in 51/54 (94.4%; failures: two inadequate haemostasis, one un-dissolved polymer). In-hospital duplex of the distal anastomosis showed a significant stenosis in two cases (4.3%). Outflow angioplasty was performed in three cases (two distal anastomotic, one run-off vessel, 5.6%). The 1-year patency rate was 76.2% (standard error (SE) 6.7%), limb salvage rate 79.3% (SE 6.7%). Amputation-free survival was 93.5% at 30 days (SE 3.6%) and 67.5% at 1 year (SE 7.5%). CONCLUSION: This thermosensitive polymer is a potentially safe and useful atraumatic device to achieve a blood-less distal anastomotic field in infra-popliteal bypasses. The technique avoids other potentially traumatic methods of vessel control, which may be particularly important in patients with calcified distal vessels.


Assuntos
Perda Sanguínea Cirúrgica/prevenção & controle , Embolização Terapêutica/métodos , Doença Arterial Periférica/cirurgia , Poloxâmero/uso terapêutico , Artéria Poplítea/cirurgia , Enxerto Vascular , Idoso , Idoso de 80 Anos ou mais , Amputação Cirúrgica , Angioplastia , Temperatura Corporal , Constrição , Embolia/etiologia , Embolia/fisiopatologia , Embolia/terapia , Embolização Terapêutica/efeitos adversos , Embolização Terapêutica/mortalidade , Feminino , Oclusão de Enxerto Vascular/etiologia , Oclusão de Enxerto Vascular/fisiopatologia , Oclusão de Enxerto Vascular/terapia , Humanos , Estimativa de Kaplan-Meier , Salvamento de Membro , Masculino , Pessoa de Meia-Idade , Doença Arterial Periférica/mortalidade , Doença Arterial Periférica/fisiopatologia , Poloxâmero/efeitos adversos , Poloxâmero/química , Artéria Poplítea/fisiopatologia , Sistema de Registros , Reoperação , Estudos Retrospectivos , Veia Safena/transplante , Fatores de Tempo , Resultado do Tratamento , Enxerto Vascular/efeitos adversos , Enxerto Vascular/mortalidade , Grau de Desobstrução Vascular
11.
Eur J Vasc Endovasc Surg ; 45(1): 46-50, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23131715

RESUMO

OBJECTIVES: Long occlusions in calcified crural arteries are a major cause of endovascular technical failure in patients with critical limb ischaemia. Therefore, distal bypasses are mainly performed in patients with heavily calcified arteries and with consequently delicate clamping. A new reverse thermosensitive polymer (RTP) is an alternative option to occlude target vessels. The aim of the study is to report our technical experience with RTP and to assess its safety and efficiency to temporarily occlude small calcified arteries during anastomosis time. METHODS: Between July 2010 and December 2011, we used RTP to occlude crural arteries in 20 consecutive patients with 20 venous distal bypasses. We recorded several operative parameters, such as volume of injected RTP, duration of occlusion and anastomotic time. Quality of occlusion was subjectively evaluated. Routine on-table angiography was performed to search for plug emboli. Primary patency, limb salvage and survival rates were reported at 6 months. RESULTS: In all patients, crural artery occlusion was achieved with the RTP without the use of an adjunct occlusion device. Mean volume of RTP used was 0.3 ml proximally and 0.25 ml distally. Mean duration of occlusion was 14.4 ± 4.5 min, while completion of the distal anastomosis lasted 13.4 ± 4.3 min. Quality of occlusion was judged as excellent in eight cases and good in 12 cases. Residual plugs were observed in two patients and removed with an embolectomy catheter, before we amended the technique for dissolution of RTP. At 6 months, primary patency rate was 75% but limb salvage rate was 87.5%. The 30-day mortality rate was 10%. CONCLUSIONS: This study shows that RTP is safe when properly dissolved and effective to occlude small calcified arteries for completion of distal anastomosis.


Assuntos
Perda Sanguínea Cirúrgica/prevenção & controle , Embolização Terapêutica/métodos , Artéria Femoral/cirurgia , Doença Arterial Periférica/cirurgia , Poloxâmero/uso terapêutico , Calcificação Vascular/complicações , Enxerto Vascular , Idoso , Idoso de 80 Anos ou mais , Temperatura Corporal , Constrição , Embolectomia , Embolia/etiologia , Embolia/fisiopatologia , Embolia/terapia , Embolização Terapêutica/efeitos adversos , Embolização Terapêutica/mortalidade , Feminino , Artéria Femoral/diagnóstico por imagem , Oclusão de Enxerto Vascular/etiologia , Oclusão de Enxerto Vascular/fisiopatologia , Oclusão de Enxerto Vascular/terapia , Humanos , Injeções Intra-Arteriais , Salvamento de Membro , Masculino , Pessoa de Meia-Idade , Doença Arterial Periférica/complicações , Doença Arterial Periférica/diagnóstico , Doença Arterial Periférica/mortalidade , Doença Arterial Periférica/fisiopatologia , Poloxâmero/administração & dosagem , Poloxâmero/efeitos adversos , Poloxâmero/química , Reoperação , Fatores de Tempo , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Ultrassonografia Doppler Dupla , Calcificação Vascular/diagnóstico , Enxerto Vascular/efeitos adversos , Enxerto Vascular/mortalidade , Grau de Desobstrução Vascular
13.
J Vasc Surg ; 55(6): 1821-5, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22301211

RESUMO

BACKGROUND: We report our initial experience with LeGoo (Pluromed Inc, Woburn, Mass), a temporary thermoreversible occlusive gel, in peripheral vascular revascularization. METHODS: Between 2007 and 2010, LeGoo was used to occlude target vessels during bypass surgery in 14 patients who required infrainguinal revascularization. RESULTS: Proximal occlusion of the target vessel was obtained with a mean quantity of 0.25 mL of LeGoo. Distal occlusion of the vessel was obtained with a mean quantity of 0.28 mL. One injection of LeGoo was sufficient to prevent backbleeding in 11 of 14 patients. The mean occlusion time was 13.4 ± 3.3 minutes. An injection of saline through the graft or better directly into the arteries was used to dissolve the gel. For our first case, a Fogarty catheter was used to remove residual gel from the anterior tibial artery. CONCLUSIONS: LeGoo gel can be used to stop blood flow in small-bore arteries in the lower limbs to allow anastomoses to be performed.


Assuntos
Perda Sanguínea Cirúrgica/prevenção & controle , Técnicas Hemostáticas , Doenças Vasculares Periféricas/cirurgia , Poloxâmero/uso terapêutico , Procedimentos Cirúrgicos Vasculares , Adulto , Idoso , Idoso de 80 Anos ou mais , Anastomose Cirúrgica , Temperatura Corporal , Constrição , Estudos de Viabilidade , Feminino , França , Humanos , Extremidade Inferior/irrigação sanguínea , Masculino , Pessoa de Meia-Idade , Doenças Vasculares Periféricas/mortalidade , Transição de Fase , Poloxâmero/efeitos adversos , Poloxâmero/química , Resultado do Tratamento , Procedimentos Cirúrgicos Vasculares/efeitos adversos , Procedimentos Cirúrgicos Vasculares/mortalidade
14.
J Appl Microbiol ; 112(6): 1173-83, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22469097

RESUMO

AIMS: CSA-13 is an antimicrobial cationic steroid with some toxicity against eukaryotic cells. The purpose of this work was to test whether pluronic acid F-127 could interfere with the toxicity of CSA-13 on human umbilical vein endothelial (HUVEC) without modifying its bactericidal activity against Pseudomonas aeruginosa. METHODS AND RESULTS: The addition of pluronic acid F-127 slightly decreased the number of dead cells after exposure to CSA-13. Pluronic acid F-127 blocked the permeabilizing effect of CSA-13 on the plasma membrane of HUVEC (uptake of ethidium bromide, release of lactate dehydrogenase) without modifying its toxic effect on their mitochondrial function (MTT test, uptake of tetramethyl rhodamine ethyl ester). CONCLUSION: Pluronic acid F-127 decreased the toxicity of CSA-13 against eukaryotic cells without completely protecting them from mitochondrial damage at high concentrations of the drug. SIGNIFICANCE AND IMPACT OF THE STUDY: This work establishes that studies on the toxic effects of synthetic antimicrobials on eukaryotic cells should not only focus on the permeability of the plasma membrane but also on the integrity of the mitochondria.


Assuntos
Antibacterianos/farmacologia , Células Eucarióticas/efeitos dos fármacos , Poloxâmero/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Esteroides/farmacologia , Antibacterianos/efeitos adversos , Etídio/metabolismo , Células Endoteliais da Veia Umbilical Humana , Humanos , L-Lactato Desidrogenase/metabolismo , Viabilidade Microbiana/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Poloxâmero/efeitos adversos , Esteroides/efeitos adversos
15.
Hum Pathol ; 119: 28-40, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34606848

RESUMO

Synthetic lifting media, ORISE™ gel and Eleview®, are increasingly used in gastrointestinal endoscopy, but neither comparative features nor pitfalls are well-established. Media histopathology, morphologic mimics, and complications are described, along with helpful stains and endoscopist media preference. A 3-year retrospective search was performed. A total of 123 cases (108 endoscopies and 15 subsequent surgeries) were identified. ORISE gel was used in 86 (79.6%), Eleview in 20 (13.9%), and others in 7 (6.5%). ORISE gel was histologically identified in 58.1% (n = 50) of endoscopic specimens and all 15 resections. Eleview media were not detected histologically. ORISE gel mimicked mucin in hematoxylin and eosin-stained biopsies, concerning for adenocarcinoma misdiagnosis and/or upstaging, but did not stain for mucin. Acid-fast bacterial staining highlights ORISE gel for specific and definitive identification. In resections, ORISE evolves into an amorphous eosinophilic material, often with exuberant giant cell reaction and transmural bowel penetration. Polyp formation leads to polypectomy in one patient, and operative lesions concerning for adenocarcinoma resulted in frozen sections in two patients. ORISE gel mimics mucin, malignant masses, amyloid, pulse granulomata, elastofibromas, and infectious granulomata. No significant endoscopist media preference was identified. Recognition of ORISE gel in tissues eliminates multiple pitfalls. Eleview was not detectable, yielded none of the pitfalls seen with ORISE gel, and, on our survey, has equivalent endoscopist acceptance. In this largest published series to date, Eleview is clearly preferable to ORISE gel.


Assuntos
Artefatos , Endoscopia Gastrointestinal/efeitos adversos , Trato Gastrointestinal/patologia , Poloxâmero/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Biópsia , Cor , Erros de Diagnóstico , Feminino , Trato Gastrointestinal/cirurgia , Géis , Humanos , Masculino , Pessoa de Meia-Idade , Poloxâmero/administração & dosagem , Valor Preditivo dos Testes , Estudos Retrospectivos , Procedimentos Desnecessários
16.
Invest New Drugs ; 29(5): 1029-37, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20179989

RESUMO

PURPOSE: To evaluate the antitumor activity of SP1049C, a novel P-glycoprotein targeting micellar formulation of doxorubicin, consisting of doxorubicin and two non-ionic block copolymers (pluronics), in patients with advanced adenocarcinoma of the esophagus and gastroesophageal junction (GEJ). PATIENTS AND METHODS: Patients with metastatic or locally advanced unresectable adenocarcinoma of the esophagus or GEJ who had not previously received systemic chemotherapy and had measurable disease were treated with SP1049C 75 mg/m(2) (doxorubicin equivalents) as a brief intravenous infusion every 3 weeks until disease progression or unacceptable toxicity. The primary endpoint was the objective response rate in patients who had received a least one course of SP1049C and had undergone tumor assessment, whereas, secondary endpoints included the objective response rate, progression-free survival (PFS), overall survival, and safety in the intent-to-treat (ITT) population. A review of scans was also conducted post-hoc by a blinded panel of radiologists. RESULTS: Twenty-one patients, of which 19 were evaluable for response, were treated with at least one dose of SP1049C. Nine patients had a partial response (PR) and eight patients had either a minor response or stable disease as their best response. The objective response rate was 47% (95% CI: 24.4-71) in the evaluable patient population, whereas the objective response rate was 43% (95% CI: 21.8-65.9) in the ITT population. The post-hoc radiological review confirmed that all nine responders had a PR; seven of the nine had a PR that was confirmed by a subsequent scan, whilst two patients had unconfirmed PRs. The median overall survival and PFS were 10.0 months (95%CI: 4.8-11.2) and 6.6 months (95% CI: 4.5-7.6), respectively. Neutropenia was the principal toxicity of SP1049C. Four patients developed an absolute percentage decrement of at least 15% in their left ventricular ejection fraction, none of which decreased to below 45% nor were symptomatic. CONCLUSION: SP1049C has a notable single-agent activity in patients with adenocarcinoma of the esophagus and GEJ, as well as an acceptable safety profile. These results, in addition to the results of preclinical studies demonstrating superior antitumor activity of SP1049C compared with doxorubicin in a standard formulation, indicate that further evaluations of SP1049C alone or combined with other relevant therapeutics in this disease setting are warranted.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Adenocarcinoma/tratamento farmacológico , Doxorrubicina/análogos & derivados , Doxorrubicina/uso terapêutico , Neoplasias Esofágicas/tratamento farmacológico , Junção Esofagogástrica/patologia , Poloxâmero/análogos & derivados , Poloxâmero/uso terapêutico , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Adenocarcinoma/patologia , Adenocarcinoma/fisiopatologia , Adulto , Idoso , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Doxorrubicina/efeitos adversos , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/fisiopatologia , Junção Esofagogástrica/fisiopatologia , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Terapia de Alvo Molecular , Estadiamento de Neoplasias , Poloxâmero/efeitos adversos , Volume Sistólico
17.
Biol Futur ; 72(2): 201-210, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34554473

RESUMO

Hyperlipidemia is one of the leading causes of, atherosclerosis, and cardiovascular disease. In this study, we evaluated the protective role of hesperidin (HES) against lipidemic stress in a hyperlipidemic model of rats. We developed a hyperlipidemic model of the rat through an i.p dose of poloxamer-407, 0.5 g/kg body weight for 3 alternative days in a week for 30 days and rats were supplemented with HES orally (100 mg/kg body weight) once daily. Bodyweight, fasting glucose, insulin, HOMA-IR index, triglyceride, cholesterol, ROS, FRAP, GSH, PMRS, AGE, MDA, PCO, AOPP, PON-1, TNF-α and IL-6, SGPT and SGOT were estimated in blood and plasma, and histopathology was done in liver tissue. Our data show that oxidative stress, inflammatory markers were increased in the P-407 treated group. Liver tissue histology also changes in the hyperlipidemic groups of rats.HES supplementation protects against P-407 induced alterations and maintains the redox homeostasis. Our results provide evidence that HES protects against lipidemic stress and redox imbalance induced by P-407 in rats.


Assuntos
Hesperidina/farmacologia , Hiperlipidemias/tratamento farmacológico , Poloxâmero/efeitos adversos , Fatores de Proteção , Animais , Modelos Animais de Doenças , Hesperidina/uso terapêutico , Hiperlipidemias/sangue , Hiperlipidemias/etiologia , Estresse Oxidativo/efeitos dos fármacos , Poloxâmero/administração & dosagem , Substâncias Protetoras/metabolismo , Ratos
18.
Int J Periodontics Restorative Dent ; 30(2): 203-11, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20228980

RESUMO

Bleaching systems and thickening agents lead to changes in the tooth enamel matrix as a result of an unspecific oxidation of the bleaching gel in the enamel. This reaction may result in a loss of mineral content and a decrease in microhardness. The aim of this study was to evaluate the effects of different bleaching systems and their thickening agents on the microhardness of human enamel in situ. Two dental slabs (3 x 3 x 2 mm) obtained from third molars were fixed on the buccal facial aspects of the maxillary first molars in a group of 45 volunteers. The volunteers were treated with 10% carbamide peroxide gel with carbopol as the thickening agent (group 1), 2% carbopol gel (group 2), 10% carbamide peroxide paste with poloxamer as the thickening agent (group 3), poloxamer (group 4), or 6.5% hydrogen peroxide strips for 21 days (group 5) (experimental treatment factor). The effects of the experimental treatment were evaluated by microhardness tests performed both before and after treatment (time factor). Data were submitted to split-plot analysis of variance and Tukey tests. Only time showed a statistically significant difference (P < .0001). All treatments reduced the enamel microhardness during treatment. Clinically, a reduction in microhardness can be expected after dental bleaching.


Assuntos
Esmalte Dentário/efeitos dos fármacos , Oxidantes/efeitos adversos , Clareamento Dental/efeitos adversos , Desmineralização do Dente/etiologia , Resinas Acrílicas , Adolescente , Adulto , Análise de Variância , Dispositivos para o Cuidado Bucal Domiciliar , Feminino , Dureza/efeitos dos fármacos , Testes de Dureza , Humanos , Masculino , Peróxidos/efeitos adversos , Poloxâmero/efeitos adversos , Polivinil/efeitos adversos , Estatísticas não Paramétricas , Adulto Jovem
19.
Am J Clin Pathol ; 153(5): 630-638, 2020 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-31875886

RESUMO

OBJECTIVES: Histologic findings after endoscopic resection using submucosal lifting agents Eleview and ORISE gel are described. METHODS: Four cases were identified based on the histologic presence of ORISE gel. Cases were selected to illustrate the histologic appearance of the lifting agent immediately after injection (day 0) and after an interval of approximately 2 months. RESULTS: Immediately after injection, the gel had an appearance similar to acellular mucin on H&E stain and showed mucicarmine positivity but was negative for periodic acid-Schiff stain and Alcian blue. At 2 months, the appearance changed drastically and was characterized by a hard, homogenous eosinophilic quality and elicited a robust foreign body-type giant cell reaction; we have proposed the name lifting agent granuloma for this histologic appearance. The aged material may be mistaken for amyloid or a pulse (legume) granuloma; however, the material was negative on Congo red stain and had a different clinical history and distribution in the tissue from those of a pulse granuloma. CONCLUSIONS: It is important to take note of the histologic appearance of these new submucosal lifting agents over a varying time interval, as outlined here, so that they are readily recognized and not mistaken for other entities.


Assuntos
Endoscopia/efeitos adversos , Granuloma de Corpo Estranho/patologia , Poloxâmero/efeitos adversos , Idoso , Feminino , Granuloma de Corpo Estranho/etiologia , Humanos , Masculino , Pessoa de Meia-Idade
20.
Am J Surg Pathol ; 44(6): 793-798, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31934919

RESUMO

Colon polypectomy can require an injection of a submucosal lifting agent to fully visualize and completely remove the polyp. To the best of our knowledge, this is the largest morphologic series on the novel lifting agents Eleview and Orise. The study consisted of 1 polypectomy and 8 colon resections from 9 patients: 6 women, 3 men (mean age=64 y); Orise=6, Eleview=3; the median time interval between injection and resection=16 weeks. Pathologic diagnoses of the polyps included tubular adenoma (n=4), tubulovillous adenoma (n=4), and sessile serrated adenoma/polyp (n=1). We report that a histologically processed Orise aliquot from the manufacturer showed similar histology to that seen in the specimens from patients with confirmed Orise injection. The morphology of the agents in the patient specimens changed with time status postinjection: immediate resection of the lifting agent showed basophilic, amorphous, and bubbly-extracellular material with prominent hemorrhage, and resection ∼3 months after lifting agent injection showed prominent hyalinized, pink-amorphous ribbons and globules with a foreign body giant cell reaction and fibrosis. The epicenter of the lifting agents was in the submucosa, and the agents were neither refractile nor polarizable. Because of the morphologic overlap with amyloid, 5 cases were stained with Congo Red, and all cases were negative. In conclusion, awareness of the morphology of these new lifting agents is important for accurate diagnosis and to avoid the diagnostic pitfall of amyloid. These lesions can be definitively distinguished from amyloid by their nonreactivity on a Congo Red and familiarity with their characteristic clinicopathologic presentation.


Assuntos
Amiloidose/patologia , Pólipos do Colo/patologia , Pólipos do Colo/cirurgia , Procedimentos Cirúrgicos do Sistema Digestório/métodos , Poloxâmero , Amiloidose/diagnóstico , Pólipos do Colo/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Poloxâmero/efeitos adversos
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