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1.
Biol Reprod ; 82(3): 552-62, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19906688

RESUMO

Studies of in vitro fertilization (IVF) and sperm cryopreservation have been conducted in several small cat species, but virtually no data exist for black-footed cats (Felis nigripes) (BFCs) or sand cats (Felis margarita) (SCs). The objectives of this study were 1) to compare in vitro motility and acrosome status of fresh and cryopreserved (frozen in pellets on dry ice or in straws in liquid nitrogen vapor) BFC and SC spermatozoa cultured in feline-optimized culture medium (FOCM) or Ham F-10, 2) to assess ovarian responsiveness in BFCs and SCs following exogenous gonadotropin treatment and laparoscopic oocyte recovery, and 3) to evaluate the fertility of fresh and frozen-thawed spermatozoa from both species using homologous and heterologous (domestic cat oocytes) IVF in the two culture media. Motility and acrosomal integrity of fresh and frozen-thawed spermatozoa from BFCs and SCs were similar (P > 0.05) in both media during 6 h of culture. Although effects were more pronounced in SCs, cryopreservation in straws was superior (P < 0.05) to cryopreservation in pellets for both species. Gonadotropin stimulation produced approximately 16 ovarian follicles per female, and >80% of recovered oocytes were of optimal (grade 1) quality. The BFC and SC spermatozoa fertilized 60.0%-79.4% of homologous and 37.7%-42.7% of heterologous oocytes in both culture media, with increased (P < 0.05) cleavage of homologous (SC) and heterologous (BFC and SC) oocytes in FOCM. These results provide the first information to date on the gamete biology of two imperiled cat species and further our capacity to apply reproductive technologies for their conservation.


Assuntos
Criopreservação/métodos , Felis , Fertilização in vitro/métodos , Preservação do Sêmen/métodos , Animais , Gatos , Células Cultivadas , Criopreservação/veterinária , Técnicas de Cultura Embrionária , Felis/fisiologia , Feminino , Fertilização in vitro/veterinária , Masculino , Recuperação de Oócitos/métodos , Recuperação de Oócitos/veterinária , Gravidez , Análise do Sêmen , Preservação do Sêmen/veterinária , Recuperação Espermática/veterinária , Espermatozoides/citologia , Espermatozoides/fisiologia
2.
Gen Comp Endocrinol ; 165(2): 204-14, 2010 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-19576217

RESUMO

Information regarding the reproductive biology of black-footed cats (BFC) and sand cats (SC) is extremely limited. Our objectives were to: (1) validate fecal hormone analysis (estrogens, E; progestagens, P; androgens, T) for noninvasive monitoring of gonadal activity; (2) characterize estrous cyclicity, ovulatory mechanisms, gestation, and seasonality; and (3) evaluate male reproductive activity via fecal androgen metabolites and ejaculate traits. In both species, the estrous cycle averaged 11-12 days. In BFC (n=8), estrus lasted 2.2+/-0.2 days with peak concentrations of E (2962.8+/-166.3 ng/g feces) increasing 2.7-fold above basal concentrations. In SC (n=6), peak concentrations of E (1669.9+/-83.5 ng/g feces) during estrus (2.9+/-0.2 days) were 4.0-fold higher than basal concentrations. Nonpregnant luteal phases occurred in 26.5% (26 of 98) of BFC estrous cycles, but were not observed in SC (0 of 109 cycles). In both species, P concentrations during pregnancy were elevated (32.3+/-3.0 microg/g feces BFC; 8.5+/-0.7 microg/g feces SC) approximately 10-fold above basal concentrations. Fecal T concentrations in males averaged 3.1+/-0.1 microg/g feces in BFC and 2.3+/-0.0 microg/g feces in SC. Following electroejaculation, 200 to 250 microl of semen was collected containing 29.9 (BFC) to 36.5 (SC)x10(6) spermatozoa with 40.4 (SC) to 46.8 (BFC)% normal morphology. All females exhibited estrous cycles during the study and spermatozoa were recovered from all males on every collection attempt, suggesting poor reproductive success in these species may not be due to physiological infertility.


Assuntos
Androgênios/metabolismo , Gatos/fisiologia , Estrogênios/metabolismo , Fezes/química , Progestinas/metabolismo , Sêmen/metabolismo , Animais , Gatos/metabolismo , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Técnicas Imunoenzimáticas , Masculino , Ovulação/metabolismo , Gravidez , Sêmen/química
3.
J Vet Pharmacol Ther ; 30(3): 257-62, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17472658

RESUMO

Marbofloxacin is a veterinary only, synthetic, broad spectrum fluoroquinolone antimicrobial agent. In mammals, approximately 40% of the oral dose of marbofloxacin is excreted unchanged in the urine; the remaining is excreted via the bile as unchanged drug in the feces. The Vd ranges from 1.1 (cattle) to 1.3 (dog, goat, swine) L/kg. Because of extra-label use of marbofloxacin in birds and reptiles, this study was designed to determine the profile of metabolites in plasma and compare the circulating metabolite profile between a reptile and an avian species. Six adult ball pythons (Python regius) and 10 blue and gold macaws (Ara ararauna) were used in this study. The macaws were dosed both i.v. and p.o. with a single 2.5 mg/kg administration where as the pythons received a single 10 mg/kg dose both i.v. and p.o. The metabolite profiles of marbofloxacin in the plasma of these species were determined using a high performance liquid chromatography system with a mass spectrometer for detection (LC/MS/MS). Mass spectra data generated from the snake and bird plasma samples were compared with previously reported LC/MS/MS mass spectral data. Evidence does not suggest differences due to route of administration (i.v. vs. p.o.) in either species. Four chromatographic peaks with resulting daughter spectrum were identified and represent 12 possible metabolite structures. All of the proposed metabolites, except for the N-oxide, appear to be unique to macaws. The potential metabolites identified in macaws appear to be very different than those reported for chickens.


Assuntos
Anti-Infecciosos/farmacocinética , Aves/metabolismo , Boidae/metabolismo , Fluoroquinolonas/farmacocinética , Quinolonas/farmacocinética , Administração Oral , Animais , Anti-Infecciosos/administração & dosagem , Anti-Infecciosos/sangue , Cromatografia Líquida/veterinária , Fezes/química , Feminino , Fluoroquinolonas/administração & dosagem , Fluoroquinolonas/sangue , Injeções Intravenosas/veterinária , Masculino , Espectrometria de Massas/veterinária , Quinolonas/administração & dosagem , Quinolonas/sangue , Especificidade da Espécie
4.
5.
Rev. méd. Chile ; 131(7): 809-814, jul. 2003.
Artigo em Espanhol | LILACS, MINSALCHILE | ID: lil-356057

RESUMO

Thirty years have elapsed since the tragic death of Salvador Allende, MD. He occupies a high position as a symbol of the fall of real socialism. He became the most famous physician/politician of his times in Chile and the tracks of his life became imprinted, during the past century, in the pages of Revista Médica de Chile. This is a proper time to reconstruct his historical memory from a more reflexive perspective.


Assuntos
Medicina Social/história , História do Século XX , Chile , Política , Política Pública
6.
J Vet Pharmacol Ther ; 26(2): 117-21, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12667181

RESUMO

Azithromycin is the first of a class of antibiotics classified as azalides. Six ball pythons (Python regius) were given a single dose of azithromycin at 10 mg/kg p.o. and i.v. in a crossover design. Serial blood samples were collected for unchanged azithromycin and to determine, if possible, the structure and number of circulating azithromycin metabolites. After a 4-month wash-out period, the snakes were given azithromycin p.o. as a single dose of 10 mg/kg for the study of azithromycin metabolism and metabolite tissue distribution. Bile, liver, lung, kidney, and skin samples were analyzed for the metabolites identified from the first experiment. Unchanged azithromycin accounted for 80, 68, and 60% of the total material at 12, 24, and 48 h postadministration in plasma, independent of route of administration. At both 24 and 72 h postadministration, azithromycin accounted for 70% of total azithromycin- associated material in bile. In liver and kidney, unchanged azithromycin accounted for 40% of the total azithromycin-associated material; this doubled in lung and skin. Fifteen metabolites were positively or tentatively identified in plasma, bile, or tissues of all snakes. Four of these possible metabolites: 3'-desamine-3-ene-azithromycin, descladinose dehydroxy-2-ene-azithromycin, 3'-desamine-3-ene descladinose-azithromycin, and 3'-N-nitroso,9a-N-desmethyl-azithromycin are unique to this species. Descladinose-azithromycin, 3'-N-desmethyl,9a-N-desmethyl-azithromycin, and 3'-N-desmethyl, 3'-O-desmethyl-azithromycin were the only metabolites identified in skin. Kidney tissue contained a greater number of metabolites than liver tissue, with 3'-N-didesmethyl-azithromycin being identified only in the kidney. Compared with the dog and cat, a greater number of metabolites were identified in ball python plasma. The percentage of unchanged azithromycin in bile is not different between the three species.


Assuntos
Antibacterianos/farmacocinética , Azitromicina/farmacocinética , Boidae/metabolismo , Administração Oral , Animais , Antibacterianos/administração & dosagem , Antibacterianos/sangue , Azitromicina/administração & dosagem , Azitromicina/sangue , Bile/metabolismo , Estudos Cross-Over , Feminino , Injeções Intravenosas/veterinária , Rim/metabolismo , Fígado/metabolismo , Pulmão/metabolismo , Masculino , Pele/metabolismo
7.
Rev Med Chil ; 129(4): 447-55, 2001 Apr.
Artigo em Espanhol | MEDLINE | ID: mdl-11413999

RESUMO

BACKGROUND: Eduardo Cruz Coke M.D., (1899-1974) was one of the precursors and pioneers of biomedical research in Chile, as professor of Physiological and Pathological Chemistry at the University of Chile, from 1925 to 1962. He was a disciple of Dr. Juan Noe and studied in Europe with the Nobel Prize winners Otto Warburg, Jean Perrin, Louis de Broglie and Frederic G. Hopkins. In Chile, he founded a scientific academy with disciples that later obtained the National Sciences Award, such as Hector Croxatto, Jorge Mardones, Hermann Niemeyer, Luis Vargas and Jorge Allende. He carried out pioneering research in metabolism, nutrition, endocrinology, oncology and nephrogenic hypertension. He published more than 50 scientific papers in French, English and Spanish. He founded scientific societies, edited journals and created the National Commission of Nuclear Energy. His books were "The ionic acidity in the clinic", "Preventive and directed medicine", "The adrenal cortex". He was Ministry of Health between 1937 and 1938 and passed important socio-medical bills. He obtained the distinguished international awards in Europe, the U.S.A. and Latin America. The Biomedical Sciences Institute of the University of Chile carries his name.


Assuntos
Fisiologia/história , Chile , História do Século XX , Pesquisa
8.
Rev Med Chil ; 129(11): 1328-32, 2001 Nov.
Artigo em Espanhol | MEDLINE | ID: mdl-11836888

RESUMO

The discovery of the complete base sequence of human genome unveils several perspectives to understand human diseases and develop new therapies. Human genome contains approximately 39,000 genes of which 26,000 code specific proteins that have been identified. There are approximately 1,500 diseases with identified molecular disturbances. Genes can modify signs and symptoms of common diseases. Thus, there are no pure monogenic diseases. Chronic diseases of adults are complex and dependent on multiple factors. Several genes that predispose to chronic degenerative diseases have been identified. This is revealing the complex nature and the interaction of these ailments with the environment. The discovery of bacterial and viral genomic sequences will allow the manufacturing of new vaccines and specific molecular antimicrobials. The new pharmacogenomics will devise treatments for each subject according to her specific genomic profile. The new applications of genomic technology is creating new paradigms in biomedical research such as functional genomics, proteonomics, epigenetic regulation. Gene diagnosis and therapy will considerably improve the future of medicine.


Assuntos
Genética Médica/tendências , Genoma Humano , Farmacogenética/tendências , Humanos
9.
Rev Med Chil ; 128(6): 679-82, 2000 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-11016069

RESUMO

The author, member of the UNESCO Bioethics Committee, participated in the preparation of the Universal Declaration about Human Genome and Human Rights, in 1997. The aim of this work is to analyze the initial articles of such Declaration, defining the bioethical principles that defend human dignity, freedom and rights, against the madness of the present biotechnological revolution. The development of genetics for the benefit of mankind will be guaranteed if these principles are honored. Genetic discrimination, reductionism and determinism, are identified by the author as perversions that, if used by biotechnologists, can lead to the rebirth of eugenism and racism, that were condemned by the Code of Nuremberg, in 1947. Investigators must assume their responsibility, respecting the principles of human dignity, the real freedom of research and solidarity among people. This attitude will avoid the use of genetics for purposes other than the welfare of mankind.


Assuntos
Bioética , Eugenia (Ciência) , Pesquisa , Nações Unidas/normas , Biotecnologia , Projeto Genoma Humano , Humanos , Preconceito
11.
Vet Clin North Am Exot Anim Pract ; 3(2): 531-6, viii, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-11228894

RESUMO

This article reviews respiratory diseases of lizards in clinics practice. A review of anatomy and physiology of the saurian respiratory tract sets the foundation for knowledge of normal function. The causes of noninfectious and infectious diseases are discussed. Diagnostic and treatment techniques to combat clinical disease are covered.


Assuntos
Criação de Animais Domésticos , Lagartos , Doenças Respiratórias/veterinária , Animais , Antibacterianos/administração & dosagem , Antibacterianos/uso terapêutico , Abrigo para Animais , Radiografia , Sistema Respiratório/diagnóstico por imagem , Doenças Respiratórias/diagnóstico , Doenças Respiratórias/tratamento farmacológico
12.
Rev Med Chil ; 127(5): 611-4, 1999 May.
Artigo em Espanhol | MEDLINE | ID: mdl-10451633

RESUMO

The art of medicine was formed in Greece in close relationship to culture and philosophy. During the Christian era, it was projected through the Corpus Hippocraticus, in several ethical and philosophical documents such as The Oath of Medical Science, Medical Law, Decency, Precepts, Antique Medicine, Airs and Aphorisms, Waters and places. The central idea of Hippocratic philosophy is the principle of wholeness, summarized by Plato in the sentence "The certain knowledge of nature is solely possible from medicine and only when it is correctly approached as a whole". Clinical actions, are imbued by Hippocratic ethics; their aim is the ill that is an anthropos, a human being. The physician must take care of the ill with devotion, selflessness, comprehension and compassion. The oath is the supreme deontological code that summarizes the essential concepts of Hippocratic philosophy. Recent studies suggest that there is a great distance between the thinking of Hippocrates and present scientific medicine. Hippocratic philosophy rejects the epistemological principles of modern science. The Hippocratic logic is probabilistic and temporal and rejects the principles of noncontradiction, of identity and therefore the abstract determinism of contemporary science. The present force of the oath is explained because its ethics and epistemology are matters of medicine that understands the real world of the ill, trying to avoid suffering and injustice. Only Hippocrates can defend each ill as a whole with the wisdom of its philosophy.


Assuntos
Juramento Hipocrático , Filosofia Médica/história , História Antiga
13.
Rev Med Chil ; 127(7): 871-2, 1999 Jul.
Artigo em Espanhol | MEDLINE | ID: mdl-10668299
14.
Rev Med Chil ; 127(12): 1524-32, 1999 Dec.
Artigo em Espanhol | MEDLINE | ID: mdl-10835762

RESUMO

The aim of this historical review is to evaluate the evolution of genetics in the context of Latin American scientific culture, to value foreign influences and to highlight the discoveries and contributions of Latin American geneticists. During the first third of the twentieth century, local naturalists, botanists and physicians understood the chromosomal theory of heredity and Mendelian theory of evolution and begun research and teaching on these new theories and technologies. During the thirties and forties, North American geneticists visited South America and formed development poles on cytogenetics and population genetics in Brazil and Argentina. During the fifties and sixties, human genetics was formally established in Brazil, Argentina and Chile. Genetics teaching became generalized in universities and national Genetics Societies were formed. In 1969, the Latin American Genetics Society was created, unifying the efforts of zoologists, botanists, physicians and anthropologists in an unique Latin American cultural space, organizing 11 meetings between 1972 and 1994. Latin Americans have made a great contribution in genome discovery of animal, vegetable and human species in their territory. They explored the great genetic diversity of the continent, discovering new genes and diseases. The biomedical area had the greatest development. In 1997, there were 130 medical genetics centers, 120 hospitals specialized in congenital malformations, 56 molecular biology centers and 26 molecular genetics centers. At the end of the twentieth century, human genetics is completely integrated to medical sciences in Latin America.


Assuntos
Genética/história , Animais , História do Século XX , Humanos , América Latina , Prêmio Nobel
15.
Rev Med Chil ; 126(11): 1393-6, 1998 Nov.
Artigo em Espanhol | MEDLINE | ID: mdl-10349185

RESUMO

BACKGROUND: In 1995, a score to measure the quality of private universities in Chile, using excellency indicators as predictors of autonomy certification, was devised by the author. AIM: To compare this score with autonomy certification results of ensuing years, to assess the usefulness of excellency indicators. MATERIAL AND METHODS: During 1995, the records of 21 private universities in Santiago were studied. These universities were qualified using eight indicators of academic excellency. These results were compared with the Superior Education Council qualification results, obtained between 1996 and 1998. RESULTS: The scores obtained by universities ranged from 19 and 137 points. Universities with the better scores obtained autonomy and those with the worst scores were eliminated. There was a good concordance between the score obtained in 1995 and the fate of autonomy certification. CONCLUSION: The best predictors and indicators of academic excellency to certificate autonomy of private universities were the magnitude of indirect budget contributed by the state, the size of academic list of staff and the percentage of admitted students with scores over 573 in the national academic aptitude tests.


Assuntos
Setor Privado , Universidades , Chile , Educação Baseada em Competências , Avaliação Educacional
16.
Rev Med Chil ; 125(6): 728-31, 1997 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-9515294

RESUMO

The author proposes the nomination of great physicians of the second half of the XIX century for a posthumous Medicine Nobel Prize. The valorization given by medical historians Garrison, Lavastine, Castiglioni, Lain Entralgo and Guerra, is used to select the better candidates. One to three names are assigned by year from 1849 to 1899. Four categories of Nobel prizes are assigned: a) Basic biological disciplines, b) Clinical and surgical medicine, pathology and specialties, c) Discoverers of transcendental diseases that are eponyms and d) New medical technologies. A total of 84 nominees for the Nobel Prize are presented. These lists are presented as preliminary and tentative to allow an extensive debate about the history of medicine during the nineteenth century.


Assuntos
Prêmio Nobel , História do Século XIX , Médicos/história
17.
Rev Med Chil ; 125(4): 492-6, 1997 Apr.
Artigo em Espanhol | MEDLINE | ID: mdl-9460293

RESUMO

In the centennial of Alfred Nobel's death, the author proposes the nomination of great physicians of XIX century for a posthumous Medicine Nobel Prize. The valorization given by medical historians such as Garrison, Lavastine, Castiglioni, Lain Entralgo and Guerra, was used to select the best candidates. One to three names were assigned per year, from 1800 to 1848. Four categories of "Romantic Nobel Prizes" are assigned: a) Founders of basic disciplines (anatomy, chemistry, physiology etc); b) Masters of clinical and surgical medicine, pathology and specialties; c) Discoverers of transcendental diseases that are eponyms and d) Other great inventors or discoverers. A total of 66 nominees for the Nobel Prize, equally distributed between French, German and English physician, are presented. The omissions and limitation of this proposals are discussed.


Assuntos
História do Século XIX , Prêmio Nobel , Europa (Continente) , Médicos/história
18.
Rev Med Chil ; 125(3): 351-7, 1997 Mar.
Artigo em Espanhol | MEDLINE | ID: mdl-9460275

RESUMO

In the last decade, two types of genes participating in the etiology of hypertension have been identified. The primary genes or blood pressure regulators are those that codify enzymes (renin, kallikrein, kininase, aminopeptidase), hormones (angiotensins, vasopressin, aldosterone, prostaglandins, and atrial natriuretic peptide) and substrates (angiotensinogen and kininogen). They cause arteriolar vasodilation or vasoconstriction or sodium retention in the extravascular space. Allelic polymorphisms associated to essential hypertension have been described. The secondary genes are those that produce hereditary diseases of low prevalence, associated to hypertension in 20 to 80% of patients (polycystic kidney disease, pheochromocytoma, adrenal hyperplasia, hereditary nephritis). Forty genes located in all chromosomes, that are dominantly, recessively or X-linked transmitted, have thus far been identified. Chromosomal maps with all genic loci are presented.


Assuntos
Genoma Humano , Hipertensão/genética , Mapeamento Cromossômico , Genes/genética , Genes Reguladores/genética , Humanos
19.
Rev Med Chil ; 125(1): 71-3, 1997 Jan.
Artigo em Espanhol | MEDLINE | ID: mdl-9336073

RESUMO

The Chilean Biological Society has approved an ethics code for researchers, elaborated by its Ethic Committee. The text, with 16 articles, undertakes the main ethical problems that researchers must solve, such as institutional, professional or societal ethics, scientific fraud, breaches in collaborative work, relationships between researchers, participation in juries and committees, ethical breaches in scientific publications, scientific responsibility and punishments. This code declares its respect and valorization of all life forms and adheres to international biomedical ethical codes. It declares that all knowledge, created or obtained by researchers is mankind's heritage.


Assuntos
Biologia , Ética Médica , Sociedades Médicas/normas , Chile , Comissão de Ética
20.
Rev Med Chil ; 123(8): 1041-4, 1995 Aug.
Artigo em Espanhol | MEDLINE | ID: mdl-8657960

RESUMO

The author reminds the reform of medical education of 1945 in which he participated as a student. It was approved by the Decree #201 of april 2, introducing Chilean medicine into a new era of modernity. The reform was planned and conducted by professors Hernán Alessandri (1900-1980) and Alejandro Garretón (1900-1980) who proposed substantial modifications in the organization, methodology and contents of curricula. An active and formative medical teaching was imposed and scientific research was encouraged. The career lasted seven years and had 27 regular and five free courses. A Teaching Commission, with eleven professors and three students, was created to fulfill such reform during the deans-hips of Garretón and Alessandri. As a consequence of the reform, national medicine was modernized in the areas of public health and hospital assistance, since the number of professors, physicians and students increased in the new Faculties created in Valparaíso, Valdivia and Temuco. The teaching-assistance and basic-clinical relationships were consolidated, with the ensuing expansion of research and medical specialties. Bringing back this reform, we appraise its impact in the progress of Chilean medicine.


Assuntos
Educação Médica/história , Chile , Educação Médica/legislação & jurisprudência , História do Século XX
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