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1.
Hand Surg Rehabil ; 38(5): 328-331, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31386922

RESUMEN

Adhesions between lumbricales and interossei muscles are known as "saddle deformities." Clinical diagnosis of saddle deformities of the hand requires a high index of clinical suspicion; this specific injury is often missed or remains undiagnosed using conventional X-ray or MRI techniques. Although the "gold standard" for treatment is surgical release of the adhesions, ultrasound-guided steroid injections at the site of adhesions could be considered a promising treatment option prior to surgical management and, as illustrated in this case, is shown to provide adequate pain relief and positive outcomes for the patient.


Asunto(s)
Glucocorticoides/administración & dosificación , Inyecciones Intramusculares , Adherencias Tisulares/tratamiento farmacológico , Ultrasonografía Intervencional , Adulto , Dexametasona/administración & dosificación , Dexametasona/análogos & derivados , Mano/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Masculino , Adherencias Tisulares/diagnóstico por imagen , Escala Visual Analógica
2.
Cytotherapy ; 7(3): 282-91, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16081355

RESUMEN

Animal and early clinical studies have provided evidence suggesting that intracoronary administration of autologous bone marrow-derived cells results in improved outcome following myocardial infarction. Animal studies with cultured marrow stromal cells (MSC) have provided similar data. Cells with properties that are similar to MSC have been identified in adipose tissue. Other groups have demonstrated in vivo differentiation of adipose tissue-derived cells (ADC) into cells exhibiting biochemical and functional markers of cardiac myocytes, including spontaneous beating. Based on these observations, the objective of the present study was to determine whether ADC might undergo similar differentiation in vivo in the context of myocardial injury.ADC were isolated from subcutaneous adipose tissue of Rosa26 mice (which express the beta-galactosidase transgene in almost every tissue) and injected into the intraventricular chamber of B6129S recipient mice immediately following induction of myocardial cryoinjury. Groups of recipients were euthanized at 24 hours, 7 and 14 days post surgery and examined for the presence of donor-derived cells within the heart.Beta-gal positive cells were identified in the infarcts of ADC-treated animals. No staining was observed in uninjured myocardium or in infarcts of control animals. Immunohistochemical analysis revealed co-expression of beta-gal with Myosin Heavy Chain, Nkx2.5 and with Troponin I. Co-expression of beta-galactosidase with Connexin 43, CD31, von Willebrand factor, MyoD or CD45 was not detected.Thus, these data indicate that adipose tissue contains a population of cells that has the ability to engraft injured myocardium and that this engraftment is associated with expression of cardiomyocytic markers by donor-derived cells.


Asunto(s)
Adipocitos/citología , Adipocitos/trasplante , Células Madre Multipotentes/citología , Infarto del Miocardio/terapia , Miocardio/citología , Adipocitos/metabolismo , Animales , Biomarcadores/metabolismo , Diferenciación Celular , Células Cultivadas , Células Endoteliales/citología , Ratones , Infarto del Miocardio/patología , Miocardio/metabolismo , Miocitos Cardíacos/citología
3.
J Bone Joint Surg Br ; 85(5): 740-7, 2003 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12892203

RESUMEN

Multipotential processed lipoaspirate (PLA) cells extracted from five human infrapatellar fat pads and embedded into fibrin glue nodules, were induced into the chondrogenic phenotype using chondrogenic media. The remaining cells were placed in osteogenic media and were transfected with an adenovirus carrying the cDNA for bone morphogenetic protein-2 (BMP-2). We evaluated the tissue-engineered cartilage and bone using in vitro techniques and by placing cells into the hind legs of five severe combined immunodeficient mice. After six weeks, radiological and histological analysis indicated that the PLA cells induced into the chondrogenic phenotype had the histological appearance of hyaline cartilage. Cells transfected with the BMP-2 gene media produced abundant bone, which was beginning to establish a marrow cavity. Tissue-engineered cartilage and bone from infrapatellar fat pads may prove to be useful for the treatment of osteochondral defects.


Asunto(s)
Cartílago Articular/citología , Condrogénesis/fisiología , Osteogénesis/fisiología , Células Madre , Ingeniería de Tejidos/métodos , Tejido Adiposo/citología , Anciano , Anciano de 80 o más Años , Animales , Técnicas de Cultivo de Célula/métodos , Modelos Animales de Enfermedad , Miembro Posterior , Humanos , Ratones , Persona de Mediana Edad , Rótula , Fenotipo , Trasplante de Células Madre/métodos
4.
J Pediatr Surg ; 36(11): 1666-71, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11685698

RESUMEN

PURPOSE: Transforming growth factor beta (TGF-beta) bioactivity has been implicated as a potential regulator of the transition from scarless healing to scar formation in fetal wounds. Decorin is an extracellular matrix proteoglycan that regulates TGF-beta bioactivity and assists in collagen fibrillogenesis. To determine its role in scarless repair, the authors examined decorin expression in fetal fibroblasts, skin, and wounds. METHODS: A single, full-thickness, 2-mm open wound was created on the dorsal surface of fetal rats at 16.5 days (E16) and 18.5 days (E18) gestational age (term, 21.5 days [E21]). Wounds were harvested at 24 and 72 hours (n = 12 wounds per time-point). Nonwounded fetal skin at E17, E19, and E21 was harvested for analysis of decorin expression during skin development and as controls for wounds. In addition, fetal (E14, E18) and adult dermal fibroblasts were cultured for in vitro analysis. Reduced-cycle, specific primer, reverse transcriptase polymerase chain reaction was performed to quantitate decorin expression. RESULTS: Decorin expression increased rapidly with increasing gestational age in both fetal fibroblasts and skin. Expression was increased 22-fold in E18 fibroblasts (P <.002) and 300-fold in adult fibroblasts (P <.001) compared with E14 fibroblasts. In skin, expression increased 74% (P <.01) during the fetal wound healing transition period between E17 and E19. However, in E16 wounds (scarless), decorin expression decreased 59% (P <.006) at 24 hours and 45% (P <.02) at 72 hours. Decorin expression did not change in E18 (scar) wounds at 24 and 72 hours (P >.05). CONCLUSIONS: Early gestation fetal fibroblasts and fetal skin express decorin at lower levels than late gestation fetal and adult fibroblasts and skin. Decorin expression is down-regulated in scarless (E16) compared with scar (E18) wounds. Thus, increased decorin expression is associated with both skin development and scar formation. Conversely, decreased decorin expression is associated with scarless repair.


Asunto(s)
Cicatriz/metabolismo , Feto/metabolismo , Fibroblastos/metabolismo , Proteoglicanos/metabolismo , Piel/metabolismo , Cicatrización de Heridas/fisiología , Animales , Cicatriz/etiología , Cicatriz/patología , Decorina , Proteínas de la Matriz Extracelular , Femenino , Fenotipo , Embarazo , Ratas , Ratas Sprague-Dawley , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Piel/citología , Factor de Crecimiento Transformador beta/metabolismo
5.
J Org Chem ; 66(20): 6654-61, 2001 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-11578217

RESUMEN

The solution-phase, parallel synthesis and evaluation of a library of 132 (+)-1,2,9,9a-tetrahydrocyclopropa[c]benz[e]indol-4-one (CBI) analogues of CC-1065 and the duocarmycins containing dimeric monocyclic, bicyclic, and tricyclic heteroaromatic replacements for the DNA-binding domain are described. This systematic study revealed clear trends in the structural requirements for observation of potent cytotoxic activity and DNA alkylation efficiency, the range of which spans a magnitude of > or =10 000-fold. Combined with related studies, these results highlight that the role of the DNA-binding domain goes beyond simply providing DNA-binding selectivity and affinity (10-100-fold enhancement in properties), consistent with the proposal that it contributes significantly to catalysis of the DNA alkylation reaction accounting for as much as an additional 1000-fold enhancement in properties.


Asunto(s)
Antibióticos Antineoplásicos/síntesis química , Antibióticos Antineoplásicos/farmacología , Leucomicinas/síntesis química , Alquilantes/síntesis química , Alquilantes/química , Alquilantes/farmacología , Alquilación/efectos de los fármacos , Antibióticos Antineoplásicos/química , Sitios de Unión , Técnicas Químicas Combinatorias , Ciclopropanos/química , ADN/metabolismo , ADN Viral/efectos de los fármacos , ADN Viral/metabolismo , Duocarmicinas , Indoles/química , Concentración 50 Inhibidora , Leucomicinas/química , Leucomicinas/farmacología , Pirroles/síntesis química , Pirroles/química , Pirroles/farmacología , Pirrolidinonas/síntesis química , Pirrolidinonas/química , Pirrolidinonas/farmacología , Virus 40 de los Simios/genética , Relación Estructura-Actividad
6.
Arch Facial Plast Surg ; 3(3): 185-89; discussion 190, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11497503

RESUMEN

BACKGROUND: The treatment of pediatric mandibular fractures is rare, controversial, and complicated by mixed dentition. OBJECTIVES: To determine if open mandibular fracture repair with intraoral and extraoral rigid plate placement, after free hand occlusal and bone reduction, without intermaxillary fixation (IMF), is appropriate and to discuss postoperative advantages, namely, maximal early return of function and minimal oral hygiene issues. PATIENTS: A group of 29 pediatric patients with a mandibular fracture were examined. Twenty pediatric patients (13 males and 7 females) with a mean age of 9 years (age range, 1-17 years) were treated using IMF. All patients were treated by the same surgeon (G.S.). RESULTS: Surgical time for plating was reduced by 1 hour, the average time to place patients in IMF. The patients who underwent open reduction internal fixation without IMF ate a soft mechanical diet by postoperative day 3 compared with postoperative day 16 for those who underwent IMF. Complication rates related to fixation technique were comparable at 20% for those who did not undergo IMF and 33% for those who did. CONCLUSIONS: We believe that free hand reduction is a valuable technique to reduce operative time for pediatric mandibular fractures. It maximizes return to function while minimizing the oral hygiene issues and hardware removal of intermaxillary function.


Asunto(s)
Fijación Interna de Fracturas/métodos , Fracturas Mandibulares/cirugía , Adolescente , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Periodo Posoperatorio , Estudios Retrospectivos
7.
J Am Chem Soc ; 123(4): 561-8, 2001 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-11456568

RESUMEN

Full details of the total syntheses of thiocoraline (1) and BE-22179 (2), C(2) symmetric bicyclic octadepsipeptides possessing two pendant 3-hydroxyquinoline chromophores, are described in which their relative and absolute stereochemistry were established. Key elements of the approach include the late-stage introduction of the chromophore, symmetrical tetrapeptide coupling, macrocyclization of the 26-membered octadepsipeptide conducted at the single secondary amide site following disulfide formation, and a convergent assemblage of the tetradepsipeptide with introduction of the labile thiol ester linkage in the final coupling reaction under near racemization free conditions. By virtue of the late-stage introduction of the chromophore and despite the challenges this imposes on the synthesis, this approach provides ready access to a range of key chromophore analogues. Thiocoraline and BE-22179 were shown to bind to DNA by high-affinity bisintercalation analogous to echinomycin, but with little or no perceptible sequence selectivity. Both 1 and 2 were found to exhibit exceptional cytotoxic activity (IC(50) = 200 and 400 pM, respectively, L1210 cell line) comparable to echinomycin and one analogue, which bears the luzopeptin chromophore, was also found to be a potent cytotoxic agent.


Asunto(s)
Antibacterianos/síntesis química , ADN/metabolismo , Depsipéptidos , Péptidos , Animales , Antibacterianos/metabolismo , Antibacterianos/farmacología , Antibióticos Antineoplásicos/síntesis química , Antibióticos Antineoplásicos/metabolismo , Antibióticos Antineoplásicos/farmacología , Bovinos , Supervivencia Celular/efectos de los fármacos , Equinomicina/metabolismo , Equinomicina/farmacología , VIH-1/enzimología , Concentración 50 Inhibidora , Ratones , Inhibidores de la Transcriptasa Inversa , Células Tumorales Cultivadas
8.
Bioorg Med Chem Lett ; 11(15): 2021-4, 2001 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-11454471

RESUMEN

A series of CBI analogues of the duocarmycins and CC-1065 exploring substituent effects within the first indole DNA binding subunit are detailed. Substitution at the indole C5 position led to cytotoxic potency enhancements that are > or =1000-fold, providing simplified analogues containing a single DNA binding subunit that are more potent (IC(50)=2-3 pM) than CBI-TMI, duocarmycin SA, or CC-1065.


Asunto(s)
Antibióticos Antineoplásicos/síntesis química , ADN/química , Leucomicinas/síntesis química , Pirroles/síntesis química , Pirrolidinonas/síntesis química , Adenina/análogos & derivados , Adenina/química , Adenina/metabolismo , Alquilación , Antibióticos Antineoplásicos/farmacología , Sitios de Unión/fisiología , ADN/metabolismo , Aductos de ADN/química , Aductos de ADN/metabolismo , Duocarmicinas , Humanos , Indoles/química , Concentración 50 Inhibidora , Leucomicinas/química , Leucomicinas/metabolismo , Leucomicinas/farmacología , Conformación de Ácido Nucleico , Pirroles/farmacología , Pirrolidinonas/farmacología , Células Tumorales Cultivadas/efectos de los fármacos
9.
J Hand Surg Am ; 26(3): 467-73, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11418909

RESUMEN

Three children with congenital constriction band syndrome affecting their upper extremities demonstrated clinical and electrophysiologic signs of a complete ulnar nerve palsy. Two of the children were diagnosed immediately postpartum with the subtle findings of an intrinsic minus posture of their hand and inability to actively extend their fingers at the proximal interphalangeal joints. One child had at least 5.5 months of intrauterine compression of the ulnar nerve detected by ultrasound examination at 18 weeks. Despite early release of the constriction bands, at 3 months in 2 children and at 6 months in 1 child, the ulnar nerve palsies persisted for a mean follow-up period of 7 years. If clinical examination of an infant with constriction band syndrome is indicative of a complete ulnar nerve palsy, the constriction band should be released as early as possible. If surgical exploration reveals significant compression of the ulnar nerve, consideration should be given to excising the involved segment of nerve with immediate primary nerve repair or nerve grafting because even early release of the constriction band does not seem to result in neurologic improvement in long-term follow-up studies.


Asunto(s)
Síndrome de Bandas Amnióticas/complicaciones , Síndromes de Compresión del Nervio Cubital/etiología , Brazo , Humanos , Recién Nacido , Masculino , Síndromes de Compresión del Nervio Cubital/diagnóstico , Síndromes de Compresión del Nervio Cubital/cirugía
10.
Tissue Eng ; 7(2): 211-28, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11304456

RESUMEN

Future cell-based therapies such as tissue engineering will benefit from a source of autologous pluripotent stem cells. For mesodermal tissue engineering, one such source of cells is the bone marrow stroma. The bone marrow compartment contains several cell populations, including mesenchymal stem cells (MSCs) that are capable of differentiating into adipogenic, osteogenic, chondrogenic, and myogenic cells. However, autologous bone marrow procurement has potential limitations. An alternate source of autologous adult stem cells that is obtainable in large quantities, under local anesthesia, with minimal discomfort would be advantageous. In this study, we determined if a population of stem cells could be isolated from human adipose tissue. Human adipose tissue, obtained by suction-assisted lipectomy (i.e., liposuction), was processed to obtain a fibroblast-like population of cells or a processed lipoaspirate (PLA). These PLA cells can be maintained in vitro for extended periods with stable population doubling and low levels of senescence. Immunofluorescence and flow cytometry show that the majority of PLA cells are of mesodermal or mesenchymal origin with low levels of contaminating pericytes, endothelial cells, and smooth muscle cells. Finally, PLA cells differentiate in vitro into adipogenic, chondrogenic, myogenic, and osteogenic cells in the presence of lineage-specific induction factors. In conclusion, the data support the hypothesis that a human lipoaspirate contains multipotent cells and may represent an alternative stem cell source to bone marrow-derived MSCs.


Asunto(s)
Adipocitos/citología , Ingeniería Biomédica , Linaje de la Célula , Separación Celular , Células Madre/citología , Tejido Adiposo/citología , Animales , Apoptosis , Terapia Biológica , Diferenciación Celular , Línea Celular , Senescencia Celular , Condrocitos/citología , Fibroblastos/citología , Citometría de Flujo , Técnica del Anticuerpo Fluorescente Indirecta , Humanos , Inmunohistoquímica , Lipectomía , Mesodermo/citología , Mesodermo/fisiología , Ratones , Músculo Esquelético/citología , Osteoblastos/citología , Piel/citología , Células Madre/fisiología , Células del Estroma , Trasplante Autólogo
11.
J Org Chem ; 66(7): 2207-16, 2001 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-11281757

RESUMEN

The synthesis of 5-methoxycarbonyl-1,2,9,9a-tetrahydrocyclopropa[c]benz[e]indol-4-one (C5-CO2Me-CBI), a substituted CBI derivative bearing a C5 methoxycarbonyl group, and its corresponding 5-hydroxymethyl derivative are described in efforts to establish substituent electronic effects on the agents' functional reactivity and the resulting effect this has on their rate of DNA alkylation. Resolution of an immediate C5-CO2Me-CBI precursor and its incorporation into both enantiomers of 16 and 17, analogues of the duocarmycins, are also detailed. A study of the solvolysis reactivity and regioselectivity of N-BOC-C5-CO2Me-CBI (12) revealed that the introduction of a C5 methyl ester modestly slowed the rate of solvolysis (1.8x, pH 3) without altering the inherent reaction regioselectivity (>20:1). The comparison of the X-ray structures of the N-CO2Me derivatives of C5-CO2Me-CBI and CBI revealed correlations with the reaction regioselectivity and the relative reactivity of the compounds. The latter correlated well with the less reactive C5-CO2Me-CBI exhibiting a shortened N2-C2a bond length (1.386 vs 1.390 A) and smaller chi1 dihedral angle (8.1 degrees vs 21.2 degrees ) indicative of greater vinylogous amide conjugation and was accompanied by a diminished (cross-conjugated) cyclopropane conjugation (shorter bond lengths). Establishment of the DNA alkyation properties revealed that C5-CO2Me-CBI-based agents retained the identical alkylation selectivity of the natural products. More importantly, the C5 methyl ester was found to decrease the rate (0.77x) of DNA alkylation relative to CBI, consistent with its inherent lower reactivity. These results indicate that the previously observed increase in the rate of DNA alkylation for C7-substituted CBI analogues including CCBI (7-cyano-CBI) is contrary to expectations based on their inherent reactivities. Unlike 17, in which the C5 methyl ester does not bind in the minor groove, the C7 substituent lies in the minor groove extending the rigid length of the agents, further enhancing the DNA binding-induced conformational change responsible for activation toward nucleophilic attack and catalysis of the DNA alkylation reaction.


Asunto(s)
Antibióticos Antineoplásicos/síntesis química , Antibióticos Antineoplásicos/farmacología , Antineoplásicos Alquilantes/síntesis química , Antineoplásicos Alquilantes/farmacología , Indoles , Leucomicinas/síntesis química , Leucomicinas/farmacología , Pirrolidinonas/síntesis química , Pirrolidinonas/farmacología , Alquilación , Animales , Antibióticos Antineoplásicos/química , Antineoplásicos Alquilantes/química , Cristalografía por Rayos X , ADN/efectos de los fármacos , ADN/metabolismo , Duocarmicinas , Concentración 50 Inhibidora , Cinética , Leucomicinas/química , Leucemia L1210/tratamiento farmacológico , Ratones , Pirroles/síntesis química , Pirroles/química , Pirroles/farmacología , Pirrolidinonas/química
12.
Plast Reconstr Surg ; 107(2): 595-7, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11214080

RESUMEN

In short, our device allows a surgeon who is harvesting adipose tissue for autologous fat transplantation to immediately, easily, efficiently, and sterilely isolate adipose tissue from the unwanted waste components that are associated with primary liposuction effluent. It does so by "trapping" the fat tissue contained within raw liposuction effluent. Once the tissue fraction has been separated, the device design then allows for direct implantation or subsequent washing/rinsing of the tissue with saline/buffer of choice in preparation for tissue reimplantation.


Asunto(s)
Tejido Adiposo/trasplante , Lipectomía/instrumentación , Recolección de Tejidos y Órganos/métodos , Diseño de Equipo , Humanos , Conservación de Tejido
13.
Physiol Biochem Zool ; 73(6): 841-9, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11121357

RESUMEN

Striated muscle contraction is initiated when troponin C (TnC) binds Ca(2+), which activates actinomyosin ATPase. We investigated (i) the variation between cardiac TnC (cTnC) primary structure within teleost fish and (ii) the pattern of TnC expression in response to temperature acclimation. There were few differences between rainbow trout (Oncorhynchus mykiss), yellowfin tuna (Thunnus albacares), yellow perch (Perca flavescens), goldfish (Carassius auratus), white sucker (Catostomus commersoni), and icefish (Chaenocephalus aceratus) in cTnC amino acid sequence. No variation existed in the regulatory Ca(2+)-binding site (site 2). The site 3 and 4 substitutions were limited to residues not directly involved in Ca(2+) coordination. Fish cTnC primary structure was highly conserved between species (93%-98%) and collectively divergent from the highly conserved sequence seen in birds and mammals. Northern blots and polymerase chain reaction showed that thermal acclimation of trout (3 degrees, 18 degrees C) did not alter the TnC isoform pattern. While cardiac and white muscle had the expected isoforms-cTnC and fast troponin C (fTnC), respectively-red muscle unexpectedly expressed primarily ftnC. Cold acclimation did not alter myofibrillar ATPase Ca(2+) sensitivity, but maximal velocity increased by 60%. We found no evidence that TnC variants, arising between species or in response to thermal acclimation, play a major role in mitigating the effects of temperature on contractility of the adult fish heart.


Asunto(s)
Regulación de la Temperatura Corporal/fisiología , Peces/fisiología , Miocardio/metabolismo , Troponina C/fisiología , Adaptación Fisiológica , Adenosina Trifosfatasas/metabolismo , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Evolución Biológica , Calcio/metabolismo , Datos de Secuencia Molecular , Miofibrillas/enzimología
14.
Bioorg Med Chem ; 8(8): 2049-57, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11003149

RESUMEN

The solution-phase synthesis of two 1000-membered positional scanning libraries of distamycin A analogues is described enlisting acid/base liquid-liquid extractions for isolation and purification of all intermediates and final products. The results of their screening for functional activity (L1210 cytotoxic potency) and DNA binding affinity were compared with those derived from libraries containing the same compound members but prepared in a smaller 10-compound mixture format. The positional scanning libraries, which are substantially less demanding to prepare, allowed the accurate detection of the global observations and the clearly more potent activities, but more subtle discoveries and less distinguishable activities were not detected. This is a natural consequence of testing the larger 100-compound mixtures and the relative insensitivity of the assays to the contribution of any single, uniquely acting compound in the mixture. Thus, the disadvantages associated with the loss of some information contained within the library must be balanced against the advantages of the ease of library synthesis and judged in light of the library screening objectives.


Asunto(s)
Técnicas Químicas Combinatorias/métodos , ADN/metabolismo , Distamicinas/química , Distamicinas/metabolismo , Biblioteca de Péptidos , Animales , Diseño de Fármacos , Ensayos de Selección de Medicamentos Antitumorales , Leucemia L1210 , Ratones , Estructura Molecular
15.
Bioorg Med Chem Lett ; 10(13): 1471-5, 2000 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-10888335

RESUMEN

The examination results of a novel series of potential inhibitors of glycinamide ribonucleotide transformylase (GAR Tfase) and aminoimidazole carboxamide transformylase (AICAR Tfase) are reported. These agents incorporate an electrophilic fluoronitrophenyl group that can potentially react with an active site nucleophile or the substrate GAR/AICAR amine via nucleophilic aromatic substitution.


Asunto(s)
Inhibidores Enzimáticos/síntesis química , Ácido Fólico/análogos & derivados , Transferasas de Hidroximetilo y Formilo/antagonistas & inhibidores , Nitrocompuestos/síntesis química , Ribonucleótidos/metabolismo , Animales , Bioensayo , Técnicas Químicas Combinatorias , Diseño de Fármacos , Inhibidores Enzimáticos/farmacología , Flúor/química , Ácido Fólico/farmacología , Estructura Molecular , Fosforribosilglicinamida-Formiltransferasa , Leucemia-Linfoma Linfoblástico de Células Precursoras , Purinas/biosíntesis , Células Tumorales Cultivadas
16.
J Org Chem ; 65(13): 4101-11, 2000 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-10866627

RESUMEN

The synthesis of 1,2,8,8a-tetrahydrocyclopropa[c]pyrrolo[3, 2-e]indol-4(5H)-one (CPI), the parent CC-1065 and duocarmycin SA alkylation subunit, is detailed. The parent CPI alkylation subunit lacks the C7 methyl substituent of the CC-1065 alkylation subunit and the C6 methoxycarbonyl group of duocarmycin SA, and their examination permitted the establishment of the impact of these natural product substituents. The studies revealed a CPI stability comparable to the CC-1065 alkylation subunit but which was 6x more reactive than the (+)-duocarmycin SA alkylation subunit, and it displayed the inherent reaction regioselectivity (4:1) of the natural products. The single-crystal X-ray structure of (+)-N-BOC-CPI depicts a near identical stereoelectronic alignment of the cyclopropane accounting for the identical reaction regioselectivity and a slightly diminished vinylogous amide conjugation relative to (+)-N-BOC-DSA suggesting that the stability distinctions stem in part from this difference in the vinylogous amide as well as alterations in the electronic nature of the fused pyrrole. Establishment of the DNA binding properties revealed that the CPI-based agents retain the identical DNA alkylation selectivities of the natural products. More importantly, the C6 methoxycarbonyl group of duocarmycin SA was found to increase the rate (12-13x) and efficiency (10x) of DNA alkylation despite its intrinsic lower reactivity while the CC-1065 C7 methyl group was found to slow the DNA alkylation rate (4x) and lower the alkylation efficiency (ca. 4x). The greater DNA alkylation rate and efficiency for duocarmycin SA and related analogues containing the C6 methoxycarbonyl is proposed to be derived from the extended length that the rigid C6 methoxycarbonyl provides and the resulting increase in the DNA binding-induced conformational change which serves to deconjugate the vinylogous amide and activate the alkylation subunit for nucleophilic attack. The diminished properties resulting from the CC-1065 C7 methyl group may be attributed to the steric impediment this substituent introduces to DNA minor groove binding and alkylation. Consistent with this behavior, the duocarmycin SA C6 methoxycarbonyl group increases biological potency while the CC-1065 C7 methyl group diminishes it.


Asunto(s)
Alquilantes/química , Antibióticos Antineoplásicos/química , ADN/química , Indolquinonas , Indoles , Leucomicinas/química , Quinolonas/síntesis química , Alquilación , Secuencia de Bases , Cristalografía por Rayos X , ADN Viral/química , Duocarmicinas , Indicadores y Reactivos , Modelos Moleculares , Conformación Molecular , Estructura Molecular , Oligodesoxirribonucleótidos/química , Pirroles/química , Quinolonas/química
19.
Plast Reconstr Surg ; 105(6): 2092-5, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-10839409

RESUMEN

To improve the outcome in patients with benign diseases of the submandibular gland, we have developed an entirely intraoral technique for excision of the submandibular gland. This procedure is anatomically safe and can be performed with minimal morbidity. We believe the essential surgical steps are as follows: (1) infiltration with Xylocaine plus epinephrine with an adequate waiting period for hemostasis; (2) careful identification of the submandibular duct/lingual nerve relationship; (3) anterior retraction of the mylohyoid muscle to expose the superficial lobe; (4) superiorly directed, extraoral, manipulation of the submandibular gland; and (5) close and blunt dissection to the gland laterally to avoid injury to the facial artery and vein.


Asunto(s)
Glándula Submandibular/cirugía , Adulto , Enfermedad Crónica , Femenino , Humanos , Masculino , Cálculos de las Glándulas Salivales/cirugía , Sialadenitis/etiología , Sialadenitis/cirugía
20.
J Org Chem ; 65(8): 2479-83, 2000 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-10789460

RESUMEN

A concise, efficient approach to the total synthesis of ningalin B (1) based on a heterocyclic azadiene Diels-Alder strategy (1,2,4,5-tetrazine-->1,2,-diazine-->pyrrole) ideally suited for construction of the densely functionalized pyrrole core found in the natural product is detailed. Examination of the natural product and a number of synthetic intermediates revealed that while lacking inherent cytotoxic activity, many reverse the multidrug-resistant (MDR) phenotype, resensitizing a human colon cancer cell line (HCT116/VM46) to vinblastine and doxorubicin at lower doses than the prototypical agent verapamil.


Asunto(s)
Antineoplásicos/síntesis química , Compuestos Heterocíclicos con 3 Anillos/síntesis química , Urocordados/química , Animales , Antibióticos Antineoplásicos/farmacología , Supervivencia Celular/efectos de los fármacos , Doxorrubicina/farmacología , Resistencia a Múltiples Medicamentos , Resistencia a Antineoplásicos , Humanos , Ratones , Células Tumorales Cultivadas
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