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1.
Geophys Res Lett ; 46(21): 11709-11717, 2019 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-31894172

RESUMO

On 10 January 2001, Cassini briefly entered into the magnetosphere of Jupiter, en route to Saturn. During this excursion into the Jovian magnetosphere, the Cassini Magnetosphere Imaging Instrument/Charge-Energy-Mass Spectrometer detected oxygen and sulfur ions. While Charge-Energy-Mass Spectrometer can distinguish between oxygen and sulfur charge states directly, only 95.9 ± 2.9 keV/e ions were sampled during this interval, allowing for a long time integration of the tenuous outer magnetospheric (~200 RJ) plasma at one energy. For this brief interval for the 95.9 keV/e ions, 96% of oxygen ions were O+, with the other 4% as O2+, while 25% of the energetic sulfur ions were S+, 42% S2+, and 33% S3+. The S2+/O+ flux ratio was observed to be 0.35 (±0.06 Poisson error).

2.
J Cell Biol ; 127(1): 95-105, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7929574

RESUMO

We show by immunohistology that distinct expression patterns of the four muscle regulatory factor (MRF) proteins identify subdomains of mouse somites. Myf-5 and MyoD are, at specific stages, each expressed in both myotome and dermatome cells. Myf-5 expression is initially restricted to dorsal cells in all somites, as is MyoD expression in neck somites. In trunk somites, however, MyoD is initially expressed in ventral cells. Myogenin and MRF4 are restricted to myotome cells, though the MRF4-expressing cells are initially less widely distributed than the myogenin-expressing cells, which are at all stages found throughout the myotome. All somitic myocytes express one or more MRFs. The transiently distinct expression patterns of the four MRF proteins identify dorsal and ventral subdomains of somites, and suggest that skeletal muscle cells in somites originate at multiple sites and via multiple molecular pathways.


Assuntos
Proteínas de Ligação a DNA , Mesoderma/química , Mesoderma/citologia , Músculo Esquelético/embriologia , Fatores de Regulação Miogênica/análise , Transativadores , Animais , Camundongos , Proteínas Musculares/análise , Proteína MyoD/análise , Fator Regulador Miogênico 5 , Miogenina/análise
3.
J Med Chem ; 21(3): 280-3, 1978 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-628003

RESUMO

The syntheses of several 13-deoxyanthracyclines are described. Koenigs-Knorr condensation of epsilon-rhodomycinone (12) with the protected daunosaminyl chloride 15 afforded 14 after deprotection. Efforts to decarbomethoxylate 12, as well as attempts to selectively deoxygenate the 13 position of daunomycinone and adriamycinone, were unsuccessful as approaches to 13-deoxyanthracyclines. However, reaction of the readily available tosylhydrazones 4 and 5, of daunorubicin and adriamycin with NaCNBH3 in acidic MeOH, afforded the 13-deoxy analogues 6 and 7 in satisfactory yield. These compounds retained antitumor activity, being comparable to the parent compounds in both efficacy and potency in the P-388 mouse leukemia screen. The epsilon-rhodomycinone glycoside 14 was less active than 6 and 7.


Assuntos
Doxorrubicina/análogos & derivados , Leucemia Experimental/tratamento farmacológico , Animais , DNA/metabolismo , Daunorrubicina/farmacologia , Doxorrubicina/síntese química , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Leucemia L1210/tratamento farmacológico , Leucemia Linfoide/tratamento farmacológico , Camundongos
4.
J Med Chem ; 22(1): 40-4, 1979 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-423182

RESUMO

Synthetic approaches to anthracyclines bearing novel 9-acyl substituents were investigated. Reaction of the lithium enolate of N-(trifluoroacetyl)daunorubicin (9) with methyl iodide in tetrahydrofuran afforded only the 9-propionyl derivative 10 in high yield. Reaction of 10 under identical conditions cleanly afforded the 9-isobutyryl derivative 11. Extension of this procedure to other alkylating agents (ethyl iodide, benzyl bromide, and heptyl iodide) required hexamethylphosphoramide as cosolvent and afforded mixtures of mono- and dialkylated products as well as recovered 9. The amino group was deblocked with NaOH in aqueous tetrahydrofuran, except in the case of the dibenzyl derivative 13 which was inert under these conditions. The 9-formyl analogue 23 was prepared via NaIO4 cleavage of 13-dihydroadriamycin (21). Antitumor evaluation against P388 leukemia in mice showed 23 to have activity comparable to the parent compounds, while the C-alkylated analogues were less active.


Assuntos
Daunorrubicina/análogos & derivados , Animais , DNA/metabolismo , DNA de Neoplasias/biossíntese , Daunorrubicina/síntese química , Daunorrubicina/farmacologia , Daunorrubicina/uso terapêutico , Leucemia L1210/metabolismo , Leucemia Experimental/tratamento farmacológico , Camundongos , RNA Neoplásico/biossíntese , Relação Estrutura-Atividade
5.
J Med Chem ; 22(8): 912-8, 1979 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-490536

RESUMO

Reaction of daunorubicin (1) and adriamycin (2) with aldehydes and ketones in the presence of NaCNBH3 afforded N-alkyl- and N,N-dialkylanthracyclines along with their 13-dihydro derivatives. Product ratios depended upon the nature of the carbonyl reagent and the starting drug. The majority of these analogues retained in vivo antitumor activity comparable to 1 and 2. However, unlike the parent compounds, which inhibit DNA and RNA synthesis at comparable concentrations, several of these analogues inhibit RNA synthesis at markedly lower concentrations than required to inhibit DNA synthesis. In addition, in some cases the ability to bind to DNA in vitro was reduced while antitumor activity was retained. N,N-Dibenzyldaunorubicin was especially notable for increased efficacy (T/C 259, qd 1--9) against P388 leukemia in mice, despite reduction of DNA binding in vitro. It showed almost complete loss of mutagenicity vs S. typhimurium (Ames test) and it was tenfold less cardiotoxic by electrocardiographic measurements (Zbinden test) in the rat.


Assuntos
Doxorrubicina/análogos & derivados , Cardiopatias/induzido quimicamente , Alquilação , Animais , Antibióticos Antineoplásicos/uso terapêutico , Fenômenos Químicos , Química , DNA/metabolismo , Doxorrubicina/síntese química , Doxorrubicina/farmacologia , Camundongos , Mutagênicos , Ratos
6.
J Med Chem ; 22(8): 922-6, 1979 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-490537

RESUMO

One-step treatment of daunomycinone with excess 2-aminoethanethiol and 2-aminoethanol in trifluoroacetic acid afforded at C-7 the thioether (77% yield) and ether (30% after recycling), respectively. Stereoselectivity for the natural 7S over the 7R configuration was greater for the ether (97:3) than for the thioether (2.5:1). Esterification of daunomycin at C-7 with beta-alanine was accomplished through the mixed anhydride of Z(OMe)-beta-alanine. Preliminary biological tests suggests that the antitumor and DNA interactive properties of the anthracyclines can be retained in such structures.


Assuntos
Daunorrubicina/análogos & derivados , Animais , Fenômenos Químicos , Química , DNA/biossíntese , Daunorrubicina/síntese química , Daunorrubicina/uso terapêutico , Depressão Química , Leucemia L1210/tratamento farmacológico , Leucemia P388/tratamento farmacológico , Camundongos
7.
J Med Chem ; 29(10): 2120-2, 1986 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-3761328

RESUMO

The susceptibility of 3'-deamino-3'-(3-cyano-4-morpholinyl)doxorubicin to hydrolysis at pH 7, 4, and 2 has been compared with that of the typically stable morpholine analogue. At pH 7, 74% of the cyanomorpholine was unchanged after 24 h at room temperature, but at pH 2 only 10% remained. Products identified were aglycon (8%) and N-(2-hydroxyethyl)doxorubicin (7%). Most of the losses were to unidentified polar products not eluted from HPLC. Authentic hydroxyethyl was synthesized from doxorubicin by reductive alkylation with glycolaldehyde. Antitumor potency was comparable to that of doxorubicin rather than of cyanomorpholine.


Assuntos
Antineoplásicos/farmacologia , Doxorrubicina/análogos & derivados , Animais , Antineoplásicos/síntese química , Linhagem Celular , Doxorrubicina/farmacologia , Resistência a Medicamentos , Concentração de Íons de Hidrogênio , Hidrólise , Leucemia P388/tratamento farmacológico , Relação Estrutura-Atividade
8.
Biotechniques ; 22(4): 752-6, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9105628

RESUMO

We have developed a universal solid support, termed Rainbow Universal CPG, for use in automated oligonucleotide synthesis. The universal solid support allows any oligodeoxyribonucleotide sequence to be synthesized from a single type of controlled pore glass (CPG) support. Deprotection of oligodeoxyribonucleotides was optimized using 0.5 M LiCl in concentrated ammonium hydroxide. PCR experiments using three different sets of primers proved that the 3'-hydroxyl function of oligodeoxyribonucleotides synthesized from Rainbow Universal CPG was retained. This universal solid support shows promise for replacing the standard nucleoside CPG supports.


Assuntos
Oligodesoxirribonucleotídeos/síntese química , Automação , Biotina , DNA Complementar , Eletroforese em Gel de Poliacrilamida , Vidro , Humanos , Cloreto de Lítio , Oligodesoxirribonucleotídeos/química , Oligodesoxirribonucleotídeos/isolamento & purificação , Placenta/química , Reação em Cadeia da Polimerase , Temperatura , Moldes Genéticos
9.
J Autism Dev Disord ; 31(4): 411-22, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11569587

RESUMO

Autism has been divided into subtypes based on social interaction/communication, developmental level, or both. The validity of subtyping systems and the extent to which they overlap were examined. According to this review, a single subtyping system capable of accounting for the symptom heterogeneity in autism has not yet been proposed; however, evidence supports the presence of a three-factor continuum containing at least four subgroups. Foremost among directions for future research is the need for comprehensive studies in which medical screening, careful selection of measures, and longitudinal data collection are included.


Assuntos
Transtorno Autístico/classificação , Transtorno Autístico/complicações , Criança , Comunicação , Humanos , Transtornos da Linguagem/complicações , Escalas de Graduação Psiquiátrica , Comportamento Social
10.
J Pharm Sci ; 68(8): 1013-5, 1979 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-383947

RESUMO

A fragment condensation method was utilized for synthesis of the Trp8-substituted luteinizing hormone-releasing hormone (LH-RH). tert-Butoxycarbonyl protection was employed for the alpha-amino positions, and benzyl protection was used for the phenol group of Tyr and the imidazole nitrogen of His. Peptide bond-forming reactions were performed using N-hydroxysuccinimide (for Trp), dicyclohexylcarbodiimide-1-hydroxybenzotriazole, 1-ethyl-3-(3'-dimethylaminopropyl)-carbodiimide hydrochloride, or mixed carbonic anhydride methods. Biological evaluation of [Trp8]-LH-RH indicated no luteinizing hormone-releasing activity or inhibition of luteinizing hormone release over the dose ranges studied.


Assuntos
Hormônio Liberador de Gonadotropina/análogos & derivados , Animais , Fenômenos Químicos , Química , Feminino , Hormônio Liberador de Gonadotropina/síntese química , Hormônio Liberador de Gonadotropina/metabolismo , Hormônio Liberador de Gonadotropina/farmacologia , Métodos , Ratos
11.
Pediatr Neurol ; 21(2): 569-72, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10465146

RESUMO

A 14-year-old female presented with common clinical findings for a rare primary intracardiac tumor. Primary cardiac tumors are rare in all age groups, occurring in 0.05% of routine postmortem examinations. Pediatric primary cardiac tumors are likewise uncommon, with the most common being a rhabdomyoma. Atrial myxomas occur infrequently in the pediatric age group. They occur primarily between the third and sixth decade, making them the most common adult primary cardiac tumor. The following case presentation demonstrates a common clinical presentation for an intracardiac mass rarely diagnosed in the pediatric population. This patient's acute neurologic symptoms required prompt recognition of an intracardiac etiology. This recognition proved critical for the acute and long-term medical and surgical management of this patient.


Assuntos
Transtornos Cerebrovasculares/etiologia , Neoplasias Cardíacas/complicações , Mixoma/complicações , Adolescente , Feminino , Átrios do Coração/diagnóstico por imagem , Átrios do Coração/patologia , Neoplasias Cardíacas/diagnóstico , Humanos , Imageamento por Ressonância Magnética , Mixoma/diagnóstico , Ultrassonografia
12.
J Pediatr Surg ; 14(6): 831-3, 1979 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-233103

RESUMO

Radiation injury to arteries can represent a significant complication of therapeutic irradiation, even when the dosage used has not been excessive as judged by approved protocols. Children in whom therapeutic abdominal irradiation has been used should be monitored indefinitely for the development of hypertension. The presence of hypertension in such children with normal blood urea nitrogen (BUN) and creatinine, and without proteinuria, should prompt investigation for a renovascular lesion. Standard bypass procedures are usually effective, although the long-term success may be compromised by continuing changes in affected vessels.


Assuntos
Hipertensão Renal/etiologia , Hipertensão Renovascular/etiologia , Lesões por Radiação , Radioterapia/efeitos adversos , Artéria Renal/efeitos da radiação , Adolescente , Criança , Humanos , Neoplasias Renais/radioterapia , Neoplasias Renais/cirurgia , Masculino , Tumor de Wilms/radioterapia , Tumor de Wilms/cirurgia
13.
J Pediatr Surg ; 15(1): 1-8, 1980 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7365651

RESUMO

Necrotizing enterocolitis (NEC) usually occurs in low birth weight infants who have had perinatal stress, and the mortality remains significant. There are a few reports of NEC in the postoperative period, especially in young infants. Nine neonates developed NEC following operations and form the basis of this report. The interval between operation and the diagnosis of NEC varied from 3 days to 4 mo. The surgical lesions included one case each of esophageal atresia, tetralogy of Fallot, supralevator rectal atresia with rectourethral fistula, and multiple intestinal atresias. Three babies had gastroschisis and two had "apple peel" intestinal atresia. Only 3 of the 9 survived. The usual clinical findings of NEC, abdominal distention, bile stained gastric residuals and diarrhea (with or without blood), can occur in the postoperative period without NEC and are, therefore, not reliable diagnostic signs. Significant changes in the clinical course of these babies occurred from 7 hr to 5 days before the diagnosis was established. In these patients the roentgen findings that established the diagnosis of NEC included intestinal ileus, pneumatosis intestinalis, and portal vein gas. Pneumatosis intestinalis and portal vein gas were the most reliable diagnostic signs, but appeared relatively late in the course of the disease. In one case pneumatosis was seen only in retrospect. None of the patients had definite pneumoperitoneum. Awareness of NEC as a potential postoperative complication may result in early recognition, treatment and survival.


Assuntos
Enterocolite Pseudomembranosa/etiologia , Doenças do Recém-Nascido/etiologia , Complicações Pós-Operatórias , Anormalidades Congênitas/cirurgia , Enterocolite Pseudomembranosa/diagnóstico , Enterocolite Pseudomembranosa/microbiologia , Enterocolite Pseudomembranosa/patologia , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Complicações Pós-Operatórias/diagnóstico , Fatores de Tempo
14.
ANZ J Surg ; 71(1): 27-31, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11167594

RESUMO

BACKGROUND: Tubular carcinoma of the breast is an uncommon and usually small tumour, and is thought to have a favourable prognosis. The present study examined the long-term prognosis of patients with tubular breast carcinoma and the roles of axillary dissection and adjuvant therapy. METHODS: Eighty-six tubular cases were identified from a large worldwide database of 9520 breast carcinoma patients entered into randomized adjuvant therapy trials run by the International Breast Cancer Study Group from 1978 to 1999. These patients were followed for a median of 12 years. RESULTS: Forty-two (49%) cases were node-positive, of which 33 (79%) had 1-3 nodes involved. Ten (32%) of the 31 smaller tumours (< or = 1 cm in size) were node-positive. Patients with node-positive tubular carcinoma had a significantly better 10-year relapse-free survival (P = 0.006) and survival (P < 0.0001) compared with non-tubular node-positive cases. Overall survival was similar for node-positive and node-negative tubular carcinoma. Overall, 71 patients (83%) received some form of adjuvant systemic therapy. Of the 86 cases, 43 (50%) received more than one course of chemotherapy. There was an 85% decrease in the risk of death for patients who received more than one course of chemotherapy compared to those who did not (hazard ratio 0.15, 95% confidence interval (CI): 0.03-0.82; P = 0.03). CONCLUSIONS: Compared to other histological types of breast cancer, tubular carcinoma has a better long-term prognosis. Adjuvant chemotherapy may further improve prognosis and involvement of axillary nodes may not be an indicator for early death due to breast carcinoma.


Assuntos
Adenocarcinoma/cirurgia , Neoplasias da Mama/cirurgia , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/secundário , Adulto , Idoso , Axila , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Quimioterapia Adjuvante , Feminino , Seguimentos , Humanos , Excisão de Linfonodo , Linfonodos/patologia , Metástase Linfática , Mastectomia , Mastectomia Segmentar , Pessoa de Meia-Idade , Prognóstico , Análise de Sobrevida
15.
Int J Pediatr Otorhinolaryngol ; 13(2): 125-42, 1987 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-3667092

RESUMO

Bilateral posterior choanal atresia is an uncommon cause of respiratory obstruction in the newborn. Although the clinical syndrome and treatment options are well known, the abnormal histology has not been well described. Computed tomography (CT) is a useful tool in the radiologic diagnosis of choanal atresia, but has not been correlated with the histopathology. Two patients with CHARGE association (congenital heart defects, choanal atresia, retarded growth and development, hypogenitalism, and aural anomalies) and bilateral posterior choanal atresia were studied with CT. The atresia plates were removed at autopsy and sectioned in an axial plane for gross and microscopic study. The histopathology is described and correlated with the CT studies. These studies show that CT accurately defines the histopathologic abnormalities found in bilateral posterior choanal atresia.


Assuntos
Atresia das Cóanas/patologia , Anormalidades Múltiplas , Atresia das Cóanas/complicações , Atresia das Cóanas/diagnóstico por imagem , Feminino , Humanos , Recém-Nascido , Masculino , Gravidez , Tomografia Computadorizada por Raios X
16.
J Am Vet Med Assoc ; 218(10): 1615-8, 1581-2, 2001 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-11393376

RESUMO

The dairy herd at Washington State University had an outbreak of mastitis caused by a single strain of Staphylococcus aureus. The outbreak strain, termed novel, could not be controlled with routine contagious mastitis pathogen control procedures (incidence, 3.4 infections/100 cow months; peak prevalence > 22%). Our objective was to implement mastitis control measures that would decrease the incidence and prevalence of intramammary infection (IMI) caused by S aureus in the herd. The following intervention strategies were successfully implemented: strict segregation of cattle with IMI caused by S aureus, intensified culling of cattle with multiple-quarter IMI caused by S aureus, and inducing cessation of lactation of infected quarters in single-mammary-quarter infected cattle. One year after implementation of these control measures, incidence of IMI caused by S aureus was 0.35 infections/100 cow months, and prevalence had decreased from 20 to 8%.


Assuntos
Indústria de Laticínios/métodos , Mastite Bovina/prevenção & controle , Infecções Estafilocócicas/veterinária , Staphylococcus aureus/isolamento & purificação , Animais , Bovinos , Contagem de Células/veterinária , Surtos de Doenças/prevenção & controle , Surtos de Doenças/veterinária , Transmissão de Doença Infecciosa/prevenção & controle , Transmissão de Doença Infecciosa/veterinária , Feminino , Controle de Infecções , Glândulas Mamárias Animais/microbiologia , Mastite Bovina/epidemiologia , Mastite Bovina/microbiologia , Leite/citologia , Leite/microbiologia , Prevalência , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/prevenção & controle , Staphylococcus aureus/classificação
17.
J Am Vet Med Assoc ; 212(4): 553-6, 1998 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-9491165

RESUMO

The Washington State University dairy experienced an outbreak of intramammary infections (IMI) caused by Staphylococcus aureus during autumn 1993 through summer 1995. The outbreak was believed to be a result of transmission of 1 strain of S aureus in a herd that historically had excellent control of contagious mastitis. Control practices included strict hygiene at time of milking and preferential culling of cows infected with S aureus. Mastitis caused by Streptococcus agalactiae was not found in this herd. Despite excellent control practices, the strain of S aureus caused a new infection rate of approximately 3% of the herd per month. Moreover, a second strain of S aureus, isolated from a cow with mastitis, was introduced into the herd experimentally, and it failed to transmit disease. The outbreak of S aureus mastitis in this herd was eventually controlled by maintaining a program of strict milking time hygiene, by intensifying the program of preferentially culling infected cows, and by segregating cows with S aureus IMI in a separate pen and milking these infected cows last.


Assuntos
Surtos de Doenças/veterinária , Mastite Bovina/epidemiologia , Infecções Estafilocócicas/veterinária , Staphylococcus aureus/classificação , Animais , Técnicas de Tipagem Bacteriana/veterinária , Bovinos , Feminino , Incidência , Mastite Bovina/microbiologia , Prevalência , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologia , Washington/epidemiologia
18.
Br Dent J ; 172(5): 208-9, 1992 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-1543637

RESUMO

'Forty years back and forty years on' was the title of the address given by Francis Manfield at the annual meeting of the RCS of England in December 1970. Francis, twice president of the Middx & Herts Branch, which this year celebrates its first 40 years, started in practice in 1930, so he was well qualified to look back over those 40 years. The aspects of change in dentistry, 1930-1970, make arresting reading more than 20 years later. His predictions for the future are equally interesting.


Assuntos
História da Odontologia , Cirurgia Bucal/história , Compostos de Tungstênio , Instrumentos Odontológicos/história , História do Século XX , Controle de Infecções/história , Lidocaína/história , Tungstênio , Reino Unido
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