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1.
RSC Adv ; 8(63): 35998-36006, 2018 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-35558441

RESUMO

A series of novel 1-(N-indolyl)-1,3-butadienes, as (1 : 1) mixtures of the (E) and (Z) dienes, was prepared in one step by base-catalysed isomerization of N-alkylindoles with a terminal butyne chain. The reaction conditions are mild, and in all cases the yields were very high (>90%). The (E) and (Z) dienes were separable by preparative TLC and could be fully characterized. This isomerization proceeded readily in the case of a butynyl chain, but didn't take place with a pentynyl chain. A mechanism was proposed for this reaction, based on previous studies on the isomerization of alkynes in basic media, and a key intermediate that supports the proposed mechanism could be isolated and fully characterized. A theoretical study of the proposed mechanism was performed by computational methods and the results validated the proposal. The reactivity of the synthesized dienes was studied in Diels-Alder reactions with p-benzoquinone, to obtain a small library of new 5-(N-indolyl)-1,4-naphthoquinones.The lack of reactivity in the case of the (Z) isomers was explained by calculation of the rotational curves of the central bond of the (Z) and (E) dienes. Finally, the cytotoxicity of the new 5-(N-indolyl)-1,4-naphthoquinones was tested against a panel of three cell lines.

2.
Nat Prod Res ; 21(6): 555-63, 2007 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-17497427

RESUMO

As part of the development of an analytical technique for the detection of meridianins and related compounds in biological fluids, a crude extract of the tunicate Aplidium meridianum was analysed using neutral loss tandem mass spectrometry. The 41 u neutral loss-EI(+) mass spectrum showed molecular ions corresponding to two previously undetected alkaloids. We report herein the isolation and structure elucidation of these alkaloids, meridianins F and G.


Assuntos
Alcaloides/análise , Alcaloides/química , Alcaloides Indólicos/análise , Alcaloides Indólicos/química , Urocordados/química , Animais , Estrutura Molecular , Espectrometria de Massas em Tandem
3.
Org Lett ; 3(10): 1415-7, 2001 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-11388830

RESUMO

[structure: see text] In the course of our search of new bioactive metabolites from marine invertebrates, paesslerins A and B, sesquiterpenoids with an unprecedented tricyclic skeleton, were isolated from the subAntarctic soft coral Alcyonium paessleri collected at a depth of 200 m near the South Georgia islands, and their structures were elucidated by spectroscopic techniques. These compounds show moderate cytotoxicity in preliminary assays.


Assuntos
Hidrocarbonetos Aromáticos com Pontes/química , Cnidários/química , Sesquiterpenos/química , Animais , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Fatores Biológicos/química , Fatores Biológicos/isolamento & purificação , Fatores Biológicos/farmacologia , Hidrocarbonetos Aromáticos com Pontes/isolamento & purificação , Hidrocarbonetos Aromáticos com Pontes/farmacologia , Humanos , Biologia Marinha , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/farmacologia , Células Tumorais Cultivadas/efeitos dos fármacos , Recursos Humanos
4.
J Org Chem ; 65(15): 4482-6, 2000 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-10959848

RESUMO

Fifteen illudalane sesquiterpenoids, alcyopterosins A-O (1-15) have been isolated from the subAntarctic soft coral Alcyonium paessleri which was collected at a depth of 200 m near the South Georgia Islands, and their structures were elucidated by spectroscopic techniques. Eight of these compounds (2, 3, 5-8, 10, and 13) are the first natural nitrate esters, while the other four (1, 4, 11, and 12) are chlorinated. These compounds are as well the first illudalane sesquiterpenoids to be isolated from the marine environment. Compounds 1, 3, 5, and 8 showed mild cytotoxicity toward human tumor cell lines.


Assuntos
Cnidários/química , Ésteres/química , Nitratos/química , Nitratos/isolamento & purificação , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Animais , Regiões Antárticas , Linhagem Celular , Ésteres/isolamento & purificação , Ésteres/toxicidade , Humanos , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Nitratos/toxicidade , Sesquiterpenos/toxicidade , Espectroscopia de Infravermelho com Transformada de Fourier
5.
Int J Radiat Oncol Biol Phys ; 47(3): 725-33, 2000 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-10837957

RESUMO

PURPOSE: To determine the toxicity, disease-free survival, and overall survival for patients with Modified Astler-Coller (MAC) B2-3 or C1-3 colon cancer receiving adjuvant radiation and sequential intraperitoneal 5-fluorouracil (5-FU). METHODS AND MATERIALS: From August 1984 to June 1989, 45 patients were accrued to this Phase II trial and received a 21-week course of intraperitoneal 5-FU (20 mg/kg/d x 5) and external beam radiation. The radiation was delivered to the tumor bed and para-aortic lymph nodes in two split-courses of 22.5 Gy, alternating with the first two cycles of chemotherapy. All patients then received 4 additional cycles of intraperitoneal 5-FU. RESULTS: The therapy was well tolerated with 4 patients experiencing Grade 3 peritonitis. Four patients developed small bowel obstruction requiring surgery; in each instance, recurrent tumor was found at the time of laparotomy. The median and overall survivals at 10 years were 9.3 months and 53% respectively. Local failures were infrequent, occurring in only 11% of patients treated. CONCLUSIONS: Sequential intraperitoneal 5-FU and tumor-bed/para-aortic irradiation is tolerable in patients with resected colon cancer. Although the incidence of local and regional relapse appeared to be lower than anticipated, this did not appear to translate into improved survival.


Assuntos
Antimetabólitos Antineoplásicos/uso terapêutico , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/radioterapia , Fluoruracila/uso terapêutico , Adulto , Idoso , Antimetabólitos Antineoplásicos/administração & dosagem , Neoplasias do Colo/patologia , Intervalo Livre de Doença , Feminino , Fluoruracila/administração & dosagem , Seguimentos , Humanos , Infusões Parenterais , Neoplasias Hepáticas/secundário , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Peritonite/etiologia , Radioterapia Adjuvante , Taxa de Sobrevida , Falha de Tratamento
6.
Minn Med ; 83(4): 41-6, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10783604

RESUMO

Cardiovascular disease is the leading cause of death in the United States. Initial results from our health survey in the Red River Valley of Minnesota suggested elevated cardiovascular mortality in men and women in younger age groups there compared with the rest of the state. Similarly, earlier published longitudinal studies of cardiovascular mortality in Minnesota revealed increased cardiovascular mortality in counties west of a diagonal line drawn through the tip of the arrowhead region (northeast Minnesota) to the southwest corner of the state. In this study we examined cardiovascular mortality by geographic region with respect to economic factors, residence patterns, and ethnic group. Since these regions vary in geology and major land use, environmental factors were considered as well. Our present data show a significant elevation in cardiovascular mortality from 1987-1997 in men and women aged 25-59 in northwest and northeast Minnesota counties compared with central-metro counties. In contrast, south-central Minnesota shows a rate of cardiovascular mortality for that age group similar to that seen in the central-metro region. The increase in cardiovascular deaths from myocardial infarct in the younger groups in the more rural, less affluent areas of northwest Minnesota is nearly two times higher than in the central-metro counties. Genetic factors may play a role in the increased mortality recorded for northeast Minnesota. Environmental contaminants such as pesticides are additional considerations. Finally, our data suggest the need to address long-standing regional cardiovascular mortality differences and rural health care access in Minnesota.


Assuntos
Doenças Cardiovasculares/mortalidade , População Rural/estatística & dados numéricos , População Urbana/estatística & dados numéricos , Adulto , Idoso , Causas de Morte , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Minnesota/epidemiologia
7.
Am J Physiol ; 276(4): H1167-71, 1999 04.
Artigo em Inglês | MEDLINE | ID: mdl-10199839

RESUMO

To investigate the role of myosin regulatory light chain isoforms as a determinant of the kinetics of cardiac contraction, unloaded shortening velocity was determined by the slack-test method in skinned wild-type murine atrial cells and transgenic cells expressing ventricular regulatory light chain (MLC2v). Transgenic mice were generated using a 4.5-kb fragment of the murine alpha-myosin heavy chain promoter to drive high levels of MLC2v expression in the atrium. Velocity of unloaded shortening was determined at 15 degrees C in maximally activating Ca2+ solution (pCa 4.5) containing (in mmol/l) 7 EGTA, 1 free Mg2+, 4 MgATP, 14.5 creatine phosphate, and 20 imidazole (ionic strength 180 mmol/l, pH 7.0). Compared with the wild type (n = 10), the unloaded shortening velocity of MLC2v-expressing transgenic murine atrial cells (n = 10) was significantly greater (3.88 +/- 1.19 vs. 2.51 +/- 1.08 muscle lengths/s, P < 0.05). These results provide evidence that myosin light chain 2 regulates cross-bridge cycling rate. The faster rate of cycling in the presence of MLC2v suggests that the MLC2v isoform may contribute to the greater power-generating capabilities of the ventricle compared with the atrium.


Assuntos
Função Atrial/fisiologia , Miocárdio/metabolismo , Cadeias Leves de Miosina/metabolismo , Animais , Cálcio/fisiologia , Expressão Gênica/fisiologia , Ventrículos do Coração , Cinética , Camundongos , Camundongos Transgênicos/genética , Contração Miocárdica/fisiologia , Miocárdio/citologia , Cadeias Leves de Miosina/genética , Fatores de Tempo , Transgenes/fisiologia
8.
J Nat Prod ; 61(9): 1130-2, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9748381

RESUMO

Five new indole alkaloids, meridianins A-E (1-5), have been isolated from the tunicate Aplidium meridianum, which was collected at a depth of 100 m near the South Georgia Islands, and their structures were elucidated by spectroscopic techniques. Compounds 2-5 showed cytotoxicity toward murine tumor cell lines.


Assuntos
Alcaloides/farmacologia , Antineoplásicos/farmacologia , Urocordados/metabolismo , Alcaloides/isolamento & purificação , Animais , Antineoplásicos/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Camundongos , Espectrofotometria Ultravioleta , Células Tumorais Cultivadas
9.
Circulation ; 97(15): 1508-13, 1998 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-9576432

RESUMO

BACKGROUND: In contrast to their well-known and critical role in excitation-contraction coupling of vascular smooth muscle, the effects of the myosin light chains on cardiomyocyte mechanics are poorly understood. Accordingly, we designed the present experiment to define the cardiac chamber-specific functional effects of the ventricular isoform of the regulatory myosin light chain (MLC2v). METHODS AND RESULTS: Postnatal transgenic cardiac-specific overexpression of MLC2v was achieved by use of the alpha-myosin heavy chain promoter. Enzymatically disaggregated atrial and ventricular mouse myocytes were field-stimulated at multiple frequencies, and mechanical properties and calcium kinetics were studied by use of video edge detection and FURA 2-AM, respectively. MLC2v overexpression resulted in complete replacement of the atrial with the ventricular isoform of the regulatory myosin light chain at the steady-state mRNA and protein levels in the atria of transgenic mice. Mechanical properties of transgenic atrial myocytes were enhanced to the level of ventricular myocytes of control animals in association with modest decreases in the amplitude of the calcium transient. CONCLUSIONS: MLC2v modulates chamber-specific contractility by enhanced calcium sensitivity and/or improved cross-bridge cycling of the thin and thick filaments of the cardiomyocyte.


Assuntos
Miosinas Cardíacas , Isoenzimas/genética , Fibras Musculares Esqueléticas/química , Miocárdio/química , Cadeias Leves de Miosina/genética , Animais , Cálcio/metabolismo , Tamanho Celular , Feminino , Expressão Gênica , Átrios do Coração/química , Átrios do Coração/citologia , Ventrículos do Coração/química , Ventrículos do Coração/citologia , Cinética , Masculino , Camundongos , Camundongos Transgênicos , Contração Muscular/fisiologia , Fibras Musculares Esqueléticas/enzimologia , Miocárdio/citologia , Miocárdio/enzimologia
10.
Circ Res ; 78(3): 504-9, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8593710

RESUMO

The structure-function relationships of the sarcomeric proteins in the mammalian cardiac compartment remain ill-defined because of the lack of a suitable model in which they can be readily manipulated or exchanged in vivo. To establish the validity of the transgenic paradigm for remodeling the mammalian heart, the murine alpha -cardiac myosin heavy chain gene promoter was used to express a ventricular myosin light chain-2 transgene (MLC2v) in both the atria and ventricles of the adult animal. Expression resulted in high levels of the transgene's transcript in both compartments. In the ventricle, the transgene was expressed against the background expression of the normal isoform. In the atrium, the transgene's expression would be ectopic, in that normally, MLC2v expression is restricted to the ventricle. Ectopic expression of the transgene in the atria resulted in a complete replacement of the atrial myosin light chain-2 protein isoform, although the endogenous isoform's steady state transcript levels were unchanged. In contrast, ventricular expression of the transgene had no effect at the protein level, despite an eightfold increase in MLC2v transcript levels. The data show that sarcomeric protein stoichiometry is maintained rigorously via posttransciptional regulation and that protein replacement can be achieved through a single transgenic manipulation.


Assuntos
Coração/fisiologia , Contração Miocárdica/genética , Miocárdio/metabolismo , Animais , Sequência de Bases , Camundongos , Camundongos Transgênicos , Dados de Sequência Molecular , Transgenes
11.
Steroids ; 61(1): 2-6, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8789728

RESUMO

The sterol composition of the Patagonian tunicate Polizoa opuntia was examined, and twenty-four compounds were identified as having either a delta 5, delta 7, or delta 0 nucleus. Two of them, the rare 20-methylpregn-5-en-3 beta-ol and 20-ethylpregn-5-en-3 beta-ol, were previously unreported as natural products from tunicates. These compounds were present only as trace components; therefore, their structures were confirmed by synthesis from suitable precursors and by comparison of the spectral and chromatographic constants of the synthetic and natural compounds.


Assuntos
Esteróis/química , Urocordados/química , Animais , Cromatografia Líquida de Alta Pressão , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Conformação Molecular , Espectrofotometria Ultravioleta
13.
Cell Mol Biol Res ; 41(6): 501-9, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8777429

RESUMO

Our objective was to test the hypothesis that, via transgenesis, one can modify the contractile protein complement of the mouse heart. Using a promoter derived from the mouse myosin heavy chain gene (alpha-MyHC), we attempted to remodel the mouse myocardium by ectopically expressing a ventricular form of the myosin light chain 2 (MLC2v) in the atrium. The ability of the heart to maintain contractile isoform stoichiometry was tested by overexpressing the cDNA in both the atria and ventricle. The promoter drove high levels of transgene expression in both cardiac compartments and was controlled in an appropriate manner during development. The data show that ectopic overexpression of a contractile protein isoform can lead to compartment specific replacement. However, if the transgene encodes the isoform that is normally present (e.g., MLC2v expressed in the ventricle), the protein levels remain unaffected, although the transgenic transcript accumulates to very high levels. The basic function and the physiologic or pathophysiologic significance of differential MLC2 isoform content was examined. Using the whole working heart preparation, we show that an MLC2a --> MLC2v shift in the atrium severely affects contractile function and performance.


Assuntos
Contração Miocárdica/genética , Miocárdio/metabolismo , Cadeias Leves de Miosina/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , DNA Complementar/isolamento & purificação , Camundongos , Camundongos Transgênicos , Dados de Sequência Molecular , Contração Miocárdica/fisiologia , Regiões Promotoras Genéticas
14.
Dev Biol ; 150(1): 99-107, 1992 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1371481

RESUMO

We have identified at the molecular level two murine myosin heavy chain (MHC) genes which encode adult skeletal isoforms. As is the case for the murine cardiac MHC genes, the genes are closely linked, head to tail. To identify the isoform encoded by each gene, we located and sequenced the 3' termini and assessed the genes' temporal and tissue-specific expression patterns using probes specific for the 3' untranslated regions. These analyses indicate that the myosin encoded by the gene located 5' in the linked pair is the murine 2A isoform. The isoform encoded by the 3'-most gene of the linked pair appears to encode an additional isoform that is expressed in a number of adult skeletal muscles. The pattern of expression of the 3'-most gene indicates that it is tightly controlled developmentally. Transcripts from this gene, when compared to those from the MHC2A and beta-MHC genes, are the predominant MHC transcripts found in the diaphragm, tongue, soleus, and masseter, indicating that it encodes a major skeletal MHC isoform.


Assuntos
Músculo Masseter/metabolismo , Miosinas/genética , Animais , Sequência de Bases , Clonagem Molecular , Expressão Gênica , Biblioteca Genômica , Camundongos , Dados de Sequência Molecular , Miocárdio/metabolismo , RNA/isolamento & purificação , Alinhamento de Sequência , Língua/metabolismo
16.
Clin Obstet Gynecol ; 27(3): 724-31, 1984 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-6548424

RESUMO

Lesbians constitute a significant minority in the practice of many gynecologists. No special skills are needed for physicians to care for lesbian patients--he or she need only use the skills needed for the expert care of any patient: knowledge, acceptance, and empathy.


Assuntos
Doenças dos Genitais Femininos/terapia , Homossexualidade , Alcoolismo/terapia , Feminino , Doenças dos Genitais Femininos/psicologia , Humanos , Distúrbios Menstruais/terapia , Relações Médico-Paciente , Infecções Sexualmente Transmissíveis/terapia , Infecções Sexualmente Transmissíveis/transmissão , Neoplasias do Colo do Útero/terapia , Doenças Vaginais/terapia
18.
Am J Med Technol ; 44(4): 301-3, 1978 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-645768

RESUMO

A committee in the St. Louis Metropolitan area has been established to promote communication and cooperation among the area's existing hospital-based programs in medical technology. Area Medical Technology Education Coordinators (AMTEC) was established three years ago primarily to facilitate the administrative functions of medical technology education and to serve as an instrument for the exchange of ideas. Its primary undertaking has been the central processing of applications to the area programs, as an aid in the admission process. In addition, a continuing education program sponsored by the committee has been established, and various "curriculum sharing" activities have been sponsored for the students enrolled in the schools. Future plans for the committee include sponsoring an on-going evaluation process of graduates by employers, and establishing a criterion-referenced question pool. The authors describe the experiences of the committee to date and plans for the implementation of future goals.


Assuntos
Ciência de Laboratório Médico/educação , Missouri , Critérios de Admissão Escolar
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