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1.
J Mater Sci Mater Med ; 25(4): 989-98, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24366467

RESUMEN

The emerging next generation of engineered tissues is based on the development of loaded scaffolds containing bioactive molecules in order to control the cellular function or to interact on the surrounding tissues. Indeed, implantation of engineered biomaterials might cause local inflammation because of the host's immune response; thereby, the use of anti-inflammatory agents, whether steroidal or nonsteroidal is required. One of the most important stages of tissue engineering is the design and the generation of a porous 3D structure, with high porosity, high interconnectivity and homogenous morphology. Various techniques have been reported in the literature for the fabrication of biodegradable scaffolds, but they suffer several limitations. In this study, for the first time, the possibility of generating 3D polymeric scaffolds loaded with an active compound by supercritical freeze extraction process is evaluated; this innovative process combines the advantages of the thermally induced phase separation process and of the supercritical carbon dioxide drying. Poly-L-lactid acid/ibuprofen composite scaffolds characterized by a 3D geometry, micrometric cellular structures and wrinkled pores walls have been obtained; moreover, homogeneous drug distribution and controlled release of the active principle have been assured.


Asunto(s)
Antiinflamatorios no Esteroideos/administración & dosificación , Antiinflamatorios no Esteroideos/química , Materiales Biocompatibles/química , Ibuprofeno/administración & dosificación , Ibuprofeno/química , Ácido Láctico/química , Polímeros/química , Andamios del Tejido/química , Sistemas de Liberación de Medicamentos , Humanos , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Conformación Molecular , Poliésteres , Porosidad , Ingeniería de Tejidos
2.
Int J Pharm ; 624: 122007, 2022 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-35820518

RESUMEN

Phosphatidylcholine (PC) vesicles loaded with Triiodothyronine (T3) were fabricated using different manufacturing methods: thin layer hydration plus sonication (TF-UF), supercritical liposome formation (SC), and microfluidic technology (MF). Vesicles obtained by MF had the lowest mean diameter (88.61 ± 44.48 nm) with a Zeta Potential of -20.1 ± 5.90 mV and loading of 10 mg/g (encapsulation efficiency: 57%). In contrast, SC vesicles showed extremely low encapsulation efficiency (<10%) probably due to T3 solubility in ethanol/carbon dioxide mixture; despite TF-UF vesicles exhibiting good size (167.7 ± 90 nm; Zp -8.50 ± 0.60 mV) and loading (10 mg/g), poor mass recovery was obtained (50% loss). MF vesicles had low cytotoxicity, and they were well enough internalized by both HeLa and human tendon stem/progenitor cells (hTSPCs). Their biological activity was also monitored in both 2D and 3D cultures of hTSPCs supplemented with therapeutical concentrations of PC/T3 nano-liposomes. 2D culture showed almost similar constitutive gene expression compared to control culture supplemented with free-T3. On the contrary, when hTPSCs 3D culture was assembled, it showed a more evident homogeneous distribution of FITC labeled vesicles within the high-density structure and a significant upregulation of cell constitutive genes, such as type I Collagen (4.8-fold; p < 0.0001) at day 7, compared to the control, suggesting that T3/PC formulation has increased T3 cytosolic concentration, thus improving cells metabolic activity. The study supported MF technology for nano-carriers fabrication and opens perspectives on the activity of PC/T3 nano-vesicles as innovative formulations for TPSCs stimulation in ECM secretion.


Asunto(s)
Liposomas , Fosfatidilcolinas , Humanos , Liposomas/química , Fosfatidilcolinas/química , Células Madre , Tecnología , Tendones , Hormonas Tiroideas
3.
Leukemia ; 10(12): 1990-2, 1996 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8946942

RESUMEN

We report the clinical, hematological and immunophenotypic characteristics from four cases of acute leukemia with interstitial deletion of chromosome 9, ie del(9)(q12-q22), as a single chromosomal abnormality. Three patients had acute myeloblastic leukemia (AML) and one T origin acute lymphoblastic leukemia (ALL). According to FAB classification, blasts were classified as M1 (two patients), M2 (one patient), and L2 (one patient). In two out of three AML cases a myelodysplastic syndrome, one AREB-t and one AREB diagnosed 6 and 11 months before respectively, preceded the onset of AML. Morphological examination showed dysgranulopoiesis, dyserythropoiesis and cytoplasmic vacuoles in two AML patients, while a strong positivity to myeloperoxidases was observed in all AML cases. As concerns immunophenotypic findings, blast cells from two of three AML patients expressed CD7 and CD34, while those from the T-ALL case displayed CD33 and CD34 along with CD7. These observations suggest that del (9q) is associated with CD7+ acute leukemia of myeloid or lymphoid lineage.


Asunto(s)
Antígenos CD7/análisis , Deleción Cromosómica , Cromosomas Humanos Par 9 , Leucemia Mieloide Aguda/genética , Linfocitos T/ultraestructura , Adolescente , Adulto , Anciano , Niño , Femenino , Humanos , Inmunofenotipificación , Masculino
4.
Pediatrics ; 93(3): 409-16, 1994 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8115199

RESUMEN

BACKGROUND: Magnetic resonance imaging (MRI) of the brain in pituitary dwarfs has revealed a previously unknown entity: ectopia of the posterior pituitary (PPE), absence or hypoplasia of the pituitary stalk and hypoplasia of the anterior pituitary. The pathogenesis of these findings was explained originally by a traumatic transection of the pituitary stalk during delivery. A high incidence of breech delivery has been reported in these groups, but the traumatic hypothesis cannot explain the findings in the relatively high percentage of patients with normal delivery, nor account for a different feature also found in other pituitary dwarfs consisting of pituitary hypoplasia with normal posterior pituitary. A second hypothesis could then been proposed, based on dysgenesis or abnormal embryonic development of both adenohypophysis and neurohypophysis. OBJECTIVE: To review the value and significance of these two different etiopathogenetic hypotheses by analyzing clinical, endocrinological, and MRI findings in a large population of pituitary dwarfs. METHODS: One hundred and one consecutive patients with congenital idiopathic growth hormone deficiency (CIGHD) were studied by MRI; they were compared with a control group of 46 healthy short children. A complete clinico-endocrinological evaluation was obtained in both patients and controls to assess the perinatal history, the pituitary-hypothalamic function, and the neurological status. MRI studies were evaluated both qualitatively and quantitatively and the pituitary volume (PV) was calculated in both patients and controls. Quantitative data were statistically analyzed to compare the mean PV of the patients with the mean PV of controls, the hormonal therapy, the single or multiple pituitary hormone deficiency, and the presence of breech delivery. RESULTS: MRI revealed PPE in 59 patients and a normal posterior pituitary (NPP) in 42. PV was extremely small in patients with PPE and in patients with NPP associated with a severely narrowed pituitary stalk; mean PV was significantly lower in CIGHD patients when compared with that of healthy short children. PV was not influenced by hormonal therapy and did not differ between patients with single and multiple pituitary hormone deficiency and between patients with normal and breech delivery. PPE patients differed from NPP patients for a higher male/female ratio (3:1 vs 1:1) and for a greater frequency of multiple pituitary hormone deficiency (49% vs 12%), breech delivery (32% vs 7%), and associated congenital brain anomalies (12% vs 7%). In PPE patients breech delivery was strongly associated with multiple pituitary hormone deficiency. CONCLUSION: On the basis of this study the traumatic hypothesis could theoretically explain the pathogenesis of PPE only in 32% of the patients with this condition. On the basis of modern understanding of embryogenesis of anterior and posterior pituitary, it is then justified to propose that a defective induction of mediobasal structure of the brain in the early embryo could account for both the complex morphological MRI abnormality and the clinico-endocrinological features encountered in all PPE patients. The close contiguity between the future pituitary and hypothalamus, the peculiar association with congenital midline brain anomalies, and the recent data about a possible role of Pit-1 gene, all support the hypothesis of a congenital defect. Finally, breech delivery can be considered not as a cause of PPE, but as an effect of the embryonic pituitary-hypothalamic abnormalities.


Asunto(s)
Enanismo Hipofisario/patología , Hipotálamo/anomalías , Hipófisis/anomalías , Adolescente , Adulto , Encéfalo/anomalías , Encéfalo/patología , Presentación de Nalgas , Niño , Preescolar , Enanismo Hipofisario/fisiopatología , Femenino , Hormona del Crecimiento/metabolismo , Humanos , Hipotálamo/patología , Imagen por Resonancia Magnética , Masculino , Quiasma Óptico/anomalías , Quiasma Óptico/patología , Hipófisis/patología , Neurohipófisis/anomalías , Neurohipófisis/patología , Embarazo
5.
Leuk Lymphoma ; 20(5-6): 513-5, 1996 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8833413

RESUMEN

We report a case of tetrasomy 8 in a patient suffering from acute myelomonocytic leukemia with extensive leukemic cutaneous infiltration. In all metaphases analyzed t( I;11)(p32;q24) was concomitantly observed. Similarly to other cases with tetrasomy 8, the patient showed monocytic involvement and poor response to chemotherapy. We conclude that this kind of cytogenetic aberration is associated with distinct morphologic and clinical features.


Asunto(s)
Aneuploidia , Cromosomas Humanos Par 11/ultraestructura , Cromosomas Humanos Par 1/ultraestructura , Cromosomas Humanos Par 8 , Leucemia Mielomonocítica Aguda/genética , Leucemia Mielomonocítica Aguda/patología , Infiltración Leucémica , Piel/patología , Translocación Genética , Anciano , Resultado Fatal , Femenino , Humanos , Cariotipificación , Masculino
6.
Anticancer Res ; 20(2B): 1253-6, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10810430

RESUMEN

BACKGROUND: The chronomodulated infusion of 5-FU, FA and oxaliplatin allows a significant increase in dose intensity and antitumor efficacy in patients with metastatic colorectal cancer. Here we investigated if substitution of oxaliplatin with cisplatin produced a similar antitumor activity in previously untreated patients with advanced colorectal cancer. METHODS: We enrolled 21 consecutively evaluated ambulatory patients with metastatic colorectal cancer. Each treatment cycle consisted of a 5-day course of continuous chronomodulated venous infusion of drugs. Daily doses were 600 mg/m2 5-FU, 150 mg/m2 FA (L-form), and 12 mg/m2 cisplatin. The cycles were repeated every 21 days. RESULTS: All patients completed at least 3 cycles. Overall a total number of 105 cycles were administered. One partial response (lasting 3 months) and 13 stable disease (lasting from 3 to 12 months) were observed. The remaining 7 patients had progression of the disease. Hematologic and gastrointestinal toxicity was always < or = G2 in all cycles. CONCLUSIONS: The results of this study discourage the substitution of cisplatin for the more active compound, oxaliplatin, in a chronomodulated schedule of infusion with 5-FU and FA in patients with metastatic colorectal cancer.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Ritmo Circadiano , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Recto/tratamiento farmacológico , Adulto , Anciano , Cisplatino/administración & dosificación , Cisplatino/farmacocinética , Neoplasias del Colon/patología , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/patología , Esquema de Medicación , Femenino , Fluorouracilo/administración & dosificación , Fluorouracilo/farmacocinética , Humanos , Infusiones Intravenosas , Leucovorina/administración & dosificación , Leucovorina/farmacocinética , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Neoplasias del Recto/patología
7.
Anticancer Res ; 18(3B): 2081-4, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9677471

RESUMEN

BACKGROUND: The survival rate for surgically resected stage III N2 non-small cell lung cancer (NSCLC) patients is less than 10%. METHODS: A phase II study of cisplatin, epirubicin, and VP-16 (PEV) was undertaken in an attempt to improve the curative potential of surgery. Forty-one patients with stage III N2 NSCLC received 3 cycles of pEV. Patients with either complete response (CR) or partial response (PR) underwent surgery and 3 additional courses of PEV. RESULTS: The response rate in the whole patient population was 58%. Eighteen patients were resected; twelve resections were complete and 6 were incomplete. Toxicity was mild and consisted mainly of myelosuppression. Twenty-six patients have died, and the median survival of all 41 patients was 18.1 months, with a 3-year survival of 23%. The median survival for those patients who were resected was 27 months with a 3-year survival of 42%. CONCLUSIONS: PEV is an effective low toxic drug combination for limited NSCLC.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Neoplasias Pulmonares/tratamiento farmacológico , Adenocarcinoma/tratamiento farmacológico , Anciano , Carcinoma de Células Grandes/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Carcinoma de Células Escamosas/tratamiento farmacológico , Quimioterapia Adyuvante , Cisplatino/administración & dosificación , Epirrubicina/administración & dosificación , Etopósido/administración & dosificación , Femenino , Humanos , Neoplasias Pulmonares/mortalidad , Masculino , Persona de Mediana Edad
8.
J Protein Chem ; 22(4): 363-9, 2003 May.
Artículo en Inglés | MEDLINE | ID: mdl-13678300

RESUMEN

Attempts to purify the inhibitor of pectin methylesterase (PMEI) from the soluble extract of ripe apricot (Prunus armeniaca) fruit led to isolation of a protein (Pa-INH) similar to PMEI, but having invertase inhibitory activity against vacuolar invertase from tomato. The molecular charge, the native and SDS-PAGE molecular weights were similar to those of PMEI. Partial amino acid sequence indicated a high level of identity with invertase inhibitors and a significant identity with PMEI. Circular dichroism analysis showed a mainly alpha-helix secondary structure for both the inhibitors and a higher thermostability of Pa-INH. Four Cys residues forming disulfide bridges in PMEI were conserved in Pa-INH. Similarly to PMEI, these residues were linked by disulfide bridges (first to second and third to fourth). The free Cys139 of PMEI is substituted by Ala in Pa-INH. The results reported in this study suggest a common structural arrangement of the two inhibitors.


Asunto(s)
Hidrolasas de Éster Carboxílico/antagonistas & inhibidores , Disulfuros/química , Inhibidores Enzimáticos/química , Prunus/química , Solanum lycopersicum/química , beta-Fructofuranosidasa/antagonistas & inhibidores , Secuencia de Aminoácidos , Cromatografía Líquida de Alta Presión , Dicroismo Circular , Inhibidores Enzimáticos/aislamiento & purificación , Inhibidores Enzimáticos/metabolismo , Inhibidores Enzimáticos/farmacología , Frutas/química , Datos de Secuencia Molecular , Alineación de Secuencia , Análisis de Secuencia de Proteína , Temperatura , Tripsina/metabolismo
9.
Farmaco Sci ; 37(2): 94-104, 1982 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-7067809

RESUMEN

The synthesis of N-substituted 1,7,7-trimethyl-2-piperidinobicyclo[2.2.1]hept-2-ene 3 carboxamides (II) by reaction of 1,7,7-trimethyl-2-piperidinobicyclo[2.2.1]hept-2-ene (I) with alkyl and aryl isocyanates, as well as the alkaline hydrolysis of (II) to N-substituted 1,7,7-trimethylbicyclo[2.2.1]heptan-2-one 3 carboxamides (III), are described. A number of compounds (II) and (III) showed strong hypotensive and bradycardiac activities in rats, as well as weak infiltration anesthesia and antiarrhythmic activity in mice. Antiacetylcholine activity in vitro is also reported.


Asunto(s)
Antihipertensivos/síntesis química , Compuestos Bicíclicos con Puentes/síntesis química , Hidrocarburos Aromáticos con Puentes/síntesis química , Acetilcolina/antagonistas & inhibidores , Anestésicos Locales/síntesis química , Animales , Antiarrítmicos/síntesis química , Presión Sanguínea/efectos de los fármacos , Fenómenos Químicos , Química , Cobayas , Frecuencia Cardíaca/efectos de los fármacos , Técnicas In Vitro , Ratones , Piperidinas/síntesis química , Ratas
10.
J Med ; 13(5-6): 411-7, 1982.
Artículo en Inglés | MEDLINE | ID: mdl-6963331

RESUMEN

Fructose-1,6-diphosphate (FDP) has been reported to exert beneficial effects on several cardiac functions. We studied the effects of FDP on the biochemical and dynamic functions of the heart in anesthetized dogs. Significant effects of FDP were noted mostly as related to pyruvate and lactate metabolism. The results seem to indicate that FDP may improve heart metabolism, and coronary function in restricted animals.


Asunto(s)
Fructosadifosfatos/administración & dosificación , Hemodinámica/efectos de los fármacos , Hexosadifosfatos/administración & dosificación , Miocardio/metabolismo , Animales , Presión Sanguínea/efectos de los fármacos , Circulación Coronaria/efectos de los fármacos , Perros , Fructosadifosfatos/farmacología , Frecuencia Cardíaca/efectos de los fármacos , Lactatos/metabolismo , Ácido Láctico , Masculino , Oxidación-Reducción/efectos de los fármacos , Piruvatos/metabolismo , Ácido Pirúvico
12.
Respiration ; 42(3): 175-83, 1981.
Artículo en Inglés | MEDLINE | ID: mdl-7313343

RESUMEN

In vitro in vivo reproterol showed intense spasmolytic effects upon the trachea and bronchi against various spasm-including agents (histamine, acetylcholine, acetyl-beta-methylcholine, 5-hydroxytryptamine, BaCl2). A comparative study with various drug used in the treatment of asthma (isoprenaline, metaproterenol, salbutamol, clenbuterol, papaverine and atropine) has been conducted.


Asunto(s)
Asma/tratamiento farmacológico , Bronquios , Metaproterenol/análogos & derivados , Músculos/efectos de los fármacos , Teofilina/análogos & derivados , Tráquea , Animales , Atropina/farmacología , Broncodilatadores/farmacología , Bovinos , Relación Dosis-Respuesta a Droga , Combinación de Medicamentos , Cobayas , Masculino , Metaproterenol/farmacología , Papaverina/farmacología , Teofilina/farmacología
13.
Farmaco Sci ; 37(1): 48-54, 1982 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-7056393

RESUMEN

The syntheses of (+/-)-1-(exo-5,6-trimethylenenorbornan--2-yl)2-propanamine (IV) starting from (exo-5-trimethylenenobornan-2-yl)acetic acid (I) or (exo-5,6-trimethylenenorbornan-2-yl)acetonitrile (II), as well as a series of amides (V) described. None of compounds (IV) and (V) showed amphetamine-like activity in mice.


Asunto(s)
Norbornanos/síntesis química , Psicotrópicos/síntesis química , Anfetamina/farmacología , Animales , Fenómenos Químicos , Química , Ratones , Actividad Motora/efectos de los fármacos , Norbornanos/farmacología
14.
Minerva Anestesiol ; 48(1-2): 13-6, 1982.
Artículo en Italiano | MEDLINE | ID: mdl-7078747

RESUMEN

Phosphocreatine has been shown having significant effects on striated skeletal musculature. In fact, it was shown, by experimental researches, that phosphocreatine interfered with the state of fatigue induced in the Mus musculus and in rats, by the swimming test.


Asunto(s)
Músculos/fisiología , Fosfocreatina/fisiología , Animales , Fatiga/fisiopatología , Masculino , Ratones , Ratas
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