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1.
J Eur Acad Dermatol Venereol ; 36(8): 1342-1348, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35470920

RESUMO

BACKGROUND: Reactivation of the varicella-zoster virus (VZV), which causes herpes zoster (HZ, synonym: shingles) in humans, can be a rare adverse reaction to vaccines. Recently, reports of cases after COVID-19 vaccination have arisen. OBJECTIVES: The aim of this study was to assess whether the frequency of HZ is found to increase after COVID-19 vaccination in a large cohort, based on real-world data. As a hypothesis, the incidence of HZ was assumed to be significantly higher in subjects who received a COVID-19 vaccine (Cohort I) vs. unvaccinated individuals (Cohort II). METHODS: The initial cohorts of 1 095 086 vaccinated and 16 966 018 unvaccinated patients were retrieved from the TriNetX database and were matched on age and gender in order to mitigate confounder bias. RESULTS: After matching, each cohort accounted for 1 095 086 patients. For the vaccinated group (Cohort I), 2204 subjects developed HZ within 60 days of COVID-19 vaccination, while among Cohort II, 1223 patients were diagnosed with HZ within 60 days after having visited the clinic for any other reason (i.e. not vaccination). The risk of developing shingles was calculated as 0.20% and 0.11% for cohort I and cohort II, respectively. The difference was statistically highly significant (P < 0.0001; log-rank test). The risk ratio and odds ratio were 1.802 (95% confidence interval [CI] = 1.680; 1.932) and 1.804 (95% CI = 1.682; 1.934). CONCLUSIONS: Consistent with the hypothesis, a higher incidence of HZ was statistically detectable post-COVID-19 vaccine. Accordingly, the eruption of HZ may be a rare adverse drug reaction to COVID-19 vaccines. Even though the molecular basis of VZV reactivation remains murky, temporary compromising of VZV-specific T-cell-mediated immunity may play a mechanistic role in post-vaccination pathogenesis of HZ. Note that VZV reactivation is a well-established phenomenon both with infections and with other vaccines (i.e. this adverse event is not COVID-19-specific).


Assuntos
Vacinas contra COVID-19 , COVID-19 , Herpes Zoster , Herpesvirus Humano 3 , Ativação Viral , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , Herpes Zoster/epidemiologia , Herpes Zoster/etiologia , Herpesvirus Humano 3/fisiologia , Humanos , Vacinação/efeitos adversos
2.
Eur J Clin Microbiol Infect Dis ; 35(2): 235-44, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26610336

RESUMO

The development of a breath test by the identification of volatile organic compounds (VOCs) emitted by cariogenic bacteria is a promising approach for caries risk assessment and early caries detection. The aim of the present study was to investigate the volatile profiles of three major cariogenic bacteria and to assess whether the obtained signatures were species-specific. Therefore, the headspaces above cultures of Streptococcus mutans, Lactobacillus salivarius and Propionibacterium acidifaciens were analysed after 24 and 48 h of cultivation using gas chromatography and mass spectrometry. A volatile database was queried for the obtained VOC profiles. Sixty-four compounds were detected within the analysed culture headspaces and were absent (36) or at least only present in minor amounts (28) in the control headspace. For S. mutans 18, for L. salivarius three and for P. acidifaciens five compounds were found to be unique signature VOCs. Database matching revealed that the identified signatures of all bacteria were unique. Furthermore, 13 of the 64 detected substances have not been previously reported to be emitted by bacteria or fungi. Specific VOC signatures were found in all the investigated bacteria cultures. The obtained results encourage further research to investigate the transferability to in vivo conditions towards the development of a breath test.


Assuntos
Testes Respiratórios/métodos , Cárie Dentária/diagnóstico , Lactobacillus/metabolismo , Propionibacterium/metabolismo , Streptococcus mutans/metabolismo , Compostos Orgânicos Voláteis/análise , Cárie Dentária/microbiologia , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Medição de Risco
3.
Theriogenology ; 76(6): 1051-7, 2011 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-21722949

RESUMO

The number of oocytes recovered from Bos taurus indicus females subjected to ovum pick-up averaged two to four times greater compared to Bos taurus taurus females. The objective of the present study was to test the hypothesis that this difference in oocyte yield was due to more preantral follicles in the ovaries of Bos indicus females. Ovaries (n = 64) from Nelore (Bos indicus) fetuses (n = 10), heifers (n = 12), and cows (n = 10), and Aberdeen Angus (Bos taurus) fetuses (n = 10), heifers (n = 12), and cows (n = 10) were cut longitudinally into halves, fixed, and processed for histological evaluation. The number of preantral follicles was estimated by counting them in each histological section, using the oocyte nucleus as a marker and employing a correction factor. The average number of preantral follicles in the ovaries of Bos indicus vs Bos taurus was (mean ± SD) 143,929 ± 64,028 vs 285,155 ± 325,195 for fetuses, 76,851 ± 78,605 vs 109,673 ± 86,078 for heifers, and 39,438 ± 31,017 vs 89,577 ± 86,315 for cows (P > 0.05). The number of preantral follicles varied greatly among individual animals within the same category, as well as between breeds. In conclusion, we inferred that the higher oocyte yield from Bos indicus females was not due to a greater ovarian reserve of preantral follicles. Therefore, mechanisms controlling follicle development after the preantral stage likely accounted for differences between Bos indicus and Bos taurus females in number of oocytes retrieved at ovum pick-up.


Assuntos
Bovinos/fisiologia , Folículo Ovariano/crescimento & desenvolvimento , Animais , Feminino , Folículo Ovariano/embriologia , Ovário/citologia , Ovário/embriologia
4.
Biochemistry ; 45(1): 42-50, 2006 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-16388579

RESUMO

The guanine nucleotide binding protein Ras plays a central role as molecular switch in cellular signal transduction. Ras cycles between a GDP-bound "off" state and a GTP-bound "on" state. Specific oncogenic mutations in the Ras protein are found in up to 30% of all human tumors. Previous 31P NMR studies had demonstrated that in liquid solution different conformational states in the GDP-bound as well as in the GTP-bound form coexist. High-field EPR spectroscopy of the GDP complexes in solution displayed differences in the ligand sphere of the wild-type complex as compared to its oncogenic mutant Ras(G12V). Only three water ligands were found in the former with respect to four in the G12V mutant [Rohrer, M. et al. (2001) Biochemistry 40, 1884-1889]. These differences were not detected in previous X-ray structures in the crystalline state. In this paper, we employ high-frequency electron nuclear double resonance (ENDOR) spectroscopy to probe the ligand sphere of the metal ion in the GDP-bound state. This technique in combination with selective isotope labeling has enabled us to detect the resonances of nuclei in the first ligand sphere of the ion with high spectral resolution. We have observed the 17O ENDOR spectra of the water ligands, and we have accurately determined the 17O hyperfine coupling with a(iso) = -0.276 mT, supporting the results of previous line shape analysis in solution. Further, the distinct resonances of the alpha-, beta-, and gamma-phosphorus of the bound nucleotides are illustrated in the 31P ENDOR spectra, and their hyperfine tensors lead to distances in agreement with the X-ray structures. Finally, 13C ENDOR spectra of uniformly 13C-labeled Ras(wt) x GDP and Ras(G12V) x GDP complexes as well as of the Ras(wt) x GppNHp and the selectively 1,4-13C-Asp labeled Ras(wt) x GDP complexes have revealed that in frozen solution only one amino acid is ligated to the ion in the GDP state, whereas two are bound in the GppNHp complex. Our results suggest that a second conformational state of the protein, if correlated with a different ligand sphere of the Mn2+ ion, is not populated in the GDP form of Ras at low temperatures in frozen solution.


Assuntos
Guanosina Difosfato/química , Metais/química , Oncogenes , Proteínas ras/química , Sítios de Ligação , Cristalografia por Raios X , Espectroscopia de Ressonância de Spin Eletrônica/métodos , Congelamento , Glicina/genética , Guanosina Difosfato/metabolismo , Guanilil Imidodifosfato/química , Guanilil Imidodifosfato/metabolismo , Humanos , Marcação por Isótopo , Metais/metabolismo , Mutação , Nucleotídeos/química , Nucleotídeos/metabolismo , Fósforo/química , Fósforo/metabolismo , Soluções/química , Valina/genética , Água/química , Proteínas ras/genética , Proteínas ras/metabolismo
5.
Magn Reson Chem ; 43 Spec no.: S248-55, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16235223

RESUMO

Within this review, we describe a home-built pulsed electron paramagnetic resonance (EPR) spectrometer operating at 180 GHz as well as the incorporation of two double resonance techniques, electron nuclear double resonance (ENDOR) and pulsed electron double resonance (PELDOR), along with first applications. Hahn-echo decays on a TEMPO/polystyrene sample are presented, demonstrating that the observation of anisotropic librational motions is possible in a very precise manner at high magnetic fields. Bisdiphenylene-phenyl-allyl is used as a model system to illustrate the performance of the setup for 1H-ENDOR using the Mims as well as the Davies sequence. Furthermore, first 1H-Mims and Davies ENDOR spectra on a biological sample, the wild-type Ras*Mn2+*GDP protein, are reported. The capability of the 180-GHz PELDOR setup is demonstrated using the three-pulse ELDOR sequence on the protein ribonucleotide reductase (RNR) subunit R2 from Escherichia coli, which contains two tyrosyl radicals at a 33 angstroms distance. At 180 GHz, orientation selectivity is observed and the modulation frequency is found to be in good agreement with theoretical predictions.


Assuntos
Espectroscopia de Ressonância de Spin Eletrônica/instrumentação , Espectroscopia de Ressonância de Spin Eletrônica/métodos , Óxidos N-Cíclicos/química , Escherichia coli/enzimologia , Radicais Livres/química , Radicais Livres/metabolismo , Guanosina Difosfato/química , Guanosina Difosfato/metabolismo , Manganês/química , Manganês/metabolismo , Poliestirenos/química , Ribonucleotídeo Redutases/química , Ribonucleotídeo Redutases/metabolismo , Tirosina/química , Tirosina/metabolismo , Proteínas ras/química , Proteínas ras/metabolismo
6.
Scand J Gastroenterol ; 38(3): 260-7, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12737440

RESUMO

BACKGROUND: Activin A, the homodimer of the activin/inhibin betaA subunit, has been shown to participate in cutaneous wound healing. In this study we intended to determine its part in gastric ulceration. METHODS: Activin A expression was studied by immunohistochemistry and in situ hybridization in acetic-acid-induced chronic gastric ulcers in rat. The dynamics of this process were also assessed by quantitative real time RT-PCR and RNase protection assays (RPA). The effects of different doses of this cytokine on epithelial and mesenchymal cell proliferation were quantitated in vitro. RESULTS: Low amounts of activin A and its mRNA were expressed by epithelia, endothelia and fibroblasts in intact gastric tissue. Granulation tissue of gastric ulcers and gastric glands adjacent to the ulcer rim expressed markedly increased amounts of activin protein as well as activin/inhibin betaA mRNA. RPA and RT-PCR studies revealed a more than 3-fold increase in the relative abundance of this mRNA. Activin A did not affect the proliferation rate of fibroblasts and epithelial cells in vitro. CONCLUSIONS: Activin A participates in gastric ulcer healing in a similar fashion as in cutaneous wounding. Its expression on protein and mRNA level is markedly increased in ulcer base and rim.


Assuntos
Ativinas/biossíntese , Ativinas/genética , Subunidades beta de Inibinas/biossíntese , Subunidades beta de Inibinas/genética , Úlcera Gástrica/genética , Úlcera Gástrica/metabolismo , Ativinas/administração & dosagem , Animais , Biomarcadores/análise , Contagem de Células , Divisão Celular/efeitos dos fármacos , Divisão Celular/fisiologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Matriz Extracelular/metabolismo , Fibroblastos/citologia , Mucosa Gástrica/citologia , Mucosa Gástrica/metabolismo , Expressão Gênica , Imuno-Histoquímica , Hibridização In Situ , Subunidades beta de Inibinas/administração & dosagem , Masculino , Mucosa/citologia , Mucosa/metabolismo , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Fatores de Tempo
7.
Mol Cell Endocrinol ; 180(1-2): 169-77, 2001 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-11451588

RESUMO

A recent study from our laboratory demonstrated a strong upregulation of activin expression during cutaneous wound healing. To further analyze the role of activin A in skin morphogenesis and wound repair, we generated transgenic mice that overexpress activin A under the control of the keratin 14 promoter. The latter targets expression of transgenes to the basal, proliferating layer of the epidermis. Hetero- as well as homozygous transgenic animals were viable and fertile. However, they were smaller than non-transgenic littermates and they had smaller ears and shorter tails. Histological analysis of their skin revealed dermal hyperthickening, mainly due to the replacement of fatty tissue by connective tissue, and an increase in suprabasal, partially differentiated epidermal layers. After cutaneous injury, a strong enhancement of granulation tissue formation was observed. Furthermore, the extent of re-epithelialization was increased in some of the wounds. These data demonstrate that activin A is a potent stimulator of the wound healing process. Using an in vivo model of local brain injury, we found that activin A also plays a significant role in the early cellular response to neuronal damage. Expression of activin mRNA and protein is markedly upregulated within a few hours of injury. If applied exogenously, recombinant activin A is capable of rescuing neurons from acute cell death. Studying the interaction between bFGF, a well-established neuroprotective agent, which is currently being tested in stroke patients, and activin A, we arrived at the unexpected conclusion that it is the strong induction of activin A by bFGF which endows the latter with its beneficial actions in patients. These findings suggest that the development of substances directly targeting activin expression or receptor binding should offer new possibilities in the acute treatment of stroke and brain trauma.


Assuntos
Ativinas/fisiologia , Encéfalo/fisiologia , Pele/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Ativinas/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Encefalopatias/metabolismo , Encefalopatias/patologia , Lesões Encefálicas/metabolismo , Lesões Encefálicas/fisiopatologia , Humanos , Pele/lesões , Pele/patologia
8.
Nat Med ; 6(7): 812-5, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10888932

RESUMO

Exogenous application of neurotrophic growth factors has emerged as a new and particularly promising approach not only to promote functional recovery after acute brain injury but also to protect neurons against the immediate effect of the injury. Among the various growth factors and cytokines studied so far, the neuroprotective and neurotrophic profile of basic fibroblast growth factor (bFGF) is the best documented. Using an animal model of acute excitotoxic brain injury, we report here that the neuroprotective action of bFGF, which is now being tested in stroke patients, depends on the induction of activin A, a member of the transforming growth factor-beta superfamily. Our evidence for this previously unknown mechanism of action of bFGF is that bFGF strongly enhanced lesion-associated induction of activin A; in the presence of the activin-neutralizing protein follistatin, bFGF was no longer capable of rescuing neurons from excitotoxic death; and recombinant activin A exerted a neuroprotective effect by itself. Our data indicate that the development of substances influencing activin expression or receptor binding should offer new ways to fight neuronal loss in ischemic and traumatic brain injury.


Assuntos
Fator 2 de Crescimento de Fibroblastos/uso terapêutico , Substâncias de Crescimento/biossíntese , Inibinas/biossíntese , Ácido Caínico/toxicidade , Fármacos Neuroprotetores/uso terapêutico , Ativinas , Animais , Encéfalo/efeitos dos fármacos , Substâncias de Crescimento/farmacologia , Hipocampo/efeitos dos fármacos , Inibinas/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/metabolismo
9.
Glia ; 30(3): 231-41, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10756073

RESUMO

Astroglial cells contribute to neuronal maintenance and function in the normal and diseased brain. Gap junctions formed predominantly by connexin43 (cx43) provide important pathways to coordinate astroglial responses. We have previously shown that fibroblast growth factor (FGF)-2, which occurs ubiquitously in the CNS, downregulates gap junction communication in cortical and striatal, but not in mesencephalic astroglial cells in vitro (Reuss et al. Glia 22:19-30, 1998). Other members of the FGF family expressed in the CNS include FGF-5 and FGF-9. We show that both FGF-5 and FGF-9, like FGF-2, downregulate astroglial gap junctions and functional coupling. However, their effects are strikingly different from different brain regions, with regard to astroglial cells. FGF-5 specifically affects mesencephalic astroglial cells without changing coupling of cortical and striatal astroglia, while FGF-9 reduces gap junctional coupling in astroglia from all three brain regions. Both cx43 mRNA and protein levels as well as functional coupling assessed by dye spreading are affected. To clarify whether brain region-specific effects of FGFs on astroglial coupling are due to differential expression of FGF receptors (FGFR), we monitored expression of the four known FGFR mRNAs in astroglial cultures by RT-PCR. Irrespective of their regional origin, astroglial cells express mRNAs for FGFR-2 and FGFR-3. In summary, our results provide evidence for an important role of FGF-2, -5, and -9 in a distinct, CNS region-specific regulation mechanism of astroglial gap junction communication. The molecular basis underlying the regionally distinct responsiveness of astrocytes to different FGFs may be sought beyond distinct FGFR expression.


Assuntos
Astrócitos/citologia , Astrócitos/metabolismo , Encéfalo/citologia , Encéfalo/metabolismo , Conexina 43/metabolismo , Fatores de Crescimento de Fibroblastos/metabolismo , Junções Comunicantes/metabolismo , Substâncias de Crescimento/metabolismo , Animais , Animais Recém-Nascidos , Western Blotting , Células Cultivadas , Fator 5 de Crescimento de Fibroblastos , Fator 9 de Crescimento de Fibroblastos , Regulação da Expressão Gênica , Imuno-Histoquímica , Reação em Cadeia da Polimerase , RNA Mensageiro/metabolismo , Ratos , Fatores de Tempo
10.
Eur J Neurosci ; 12(1): 376-80, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10651893

RESUMO

Recent studies have suggested a role of connective tissue growth factor (CTGF) in repair processes of the skin as well as in various types of fibrotic disease. However, a function of this molecule in central nervous system (CNS) repair has not been demonstrated yet. In this study we analysed the temporal and spatial expression pattern of CTGF after unilateral kainic acid lesions of the hippocampal CA3 region in mice. We found a strong induction of CTGF mRNA and protein expression in neurons and glial cells of the lesioned hippocampus. Interestingly, increased expression of this mitogen was accompanied by elevated levels of the extracellular matrix molecule fibronectin, which is a known target of CTGF action. Therefore, our data indicate a novel function of CTGF in postlesional restructuring of the hippocampus, where it possibly participates in glial scar formation.


Assuntos
Lesões Encefálicas/fisiopatologia , Regulação da Expressão Gênica , Substâncias de Crescimento/genética , Hipocampo/metabolismo , Proteínas Imediatamente Precoces/genética , Peptídeos e Proteínas de Sinalização Intercelular , Animais , Lesões Encefálicas/metabolismo , Fator de Crescimento do Tecido Conjuntivo , Fibronectinas/genética , Lateralidade Funcional , Regulação da Expressão Gênica/efeitos dos fármacos , Proteína Glial Fibrilar Ácida/análise , Substâncias de Crescimento/análise , Hipocampo/patologia , Proteínas Imediatamente Precoces/análise , Ácido Caínico/toxicidade , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fatores de Tempo
11.
Berl Munch Tierarztl Wochenschr ; 112(6-7): 239-42, 1999.
Artigo em Alemão | MEDLINE | ID: mdl-10472722

RESUMO

Based on results of holter ecg recordings taken from 38 dogs the computerized analyses system turned out as method not exactly valuing the frequency and sensitivity of arrhythmias. Despite there was a significant correlation between the computerized and visual arrhythmia analysis for ventricular respectively supraventricular premature beats, in individual cases there was an important aberration between the particular values.


Assuntos
Arritmias Cardíacas/veterinária , Doenças do Cão/fisiopatologia , Eletrocardiografia Ambulatorial/veterinária , Eletrocardiografia/veterinária , Animais , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/fisiopatologia , Complexos Atriais Prematuros/diagnóstico , Complexos Atriais Prematuros/fisiopatologia , Complexos Atriais Prematuros/veterinária , Doenças do Cão/diagnóstico , Cães , Eletrocardiografia/métodos , Eletrocardiografia Ambulatorial/métodos , Ventrículos do Coração , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
12.
Health Prog ; 78(2): 39-42, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-10166698

RESUMO

When St. Joseph's Hospital in St. Paul, MN, owned and operated by the Sisters of St. Joseph of Carondelet, joined the ecumenical HealthEast healthcare system in 1987, many observers were skeptical of the venture's success. But an emphasis on their shared Judeo-Christian values has enabled the Catholic, Lutheran, and Baptist facilities to build a strong system. The beginnings of the merger were difficult, as facilities closed, others expanded their services, and staff shifted between them. An open communications policy between HealthEast leaders and staff members and dedication to the mission of healthcare that all the system facilities shared helped blend denominational identity and traditions at each member hospital and establish a corporate identity. The HealthEast system has adopted some of St. Joseph's policies and practices, particularly in the areas of mission, ethics, and spiritual care. HealthEast St. Joseph's has also benefited from being part of the HealthEast system, gaining a more diverse staff respectful of each others' beliefs, expanded spiritual care, and the means to continue serving its community. HealthEast plans to discontinue inpatient services at HealthEast St. Joseph's in downtown St. Paul and build a suburban facility, but the Sisters of St. Joseph of Carondelet are working with HealthEast to assess the downtown community's healthcare needs, especially among the homeless and immigrant populations, and ensure those needs will continue to be met.


Assuntos
Cristianismo , Instituições Associadas de Saúde , Hospitais Religiosos/organização & administração , Cultura Organizacional , Catolicismo , Ética Institucional , Hospitais Religiosos/normas , Minnesota , Objetivos Organizacionais , Valores Sociais
13.
Tierarztl Prax ; 24(2): 144-8, 1996 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-8650683

RESUMO

Holter monitoring was obtained from 44 clinically normal dogs and 68 dogs with heart disease or being suspicious for a cardiopathy. Several employments of the holter monitoring are shown by means of some examples. This method proved to be effective in the diagnosis of syncopes and the review of the therapy of arrhythmias. Limits and difficulties are discussed.


Assuntos
Doenças do Cão/fisiopatologia , Cães/fisiologia , Eletrocardiografia Ambulatorial/veterinária , Cardiopatias/veterinária , Animais , Doenças do Cão/diagnóstico , Feminino , Cardiopatias/diagnóstico , Cardiopatias/fisiopatologia , Masculino
14.
Cardiovasc Surg ; 2(6): 693-7, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7858986

RESUMO

Although calcification and degeneration are recognized as the main causes of bioprosthetic heart valve failure, the reasons for such failure are not well understood. Hidden tissue anomalies in the valves may be the origin of later calcification. Application of hologram interferometry for non-destructive testing enables the detection of such tissue anomalies. A comparative study by holographic interferometry of ten porcine bioprosthetic valves (seven Carpentier-Edwards SAV, two BioImplant and one Valcor) with five human aortic valves before and after glutaraldehyde treatment is presented. Whereas irregularities were detected in the interferograms of eight out of ten bioprostheses, no similar distorted fringe pattern was found in the holographic interferograms of human specimens. The present results suggest that tissue abnormalities exist in standard bioprosthetic valves which are absent in human ones. These irregularities may be the origin of later calcification and valvular dysfunction.


Assuntos
Bioprótese , Próteses Valvulares Cardíacas , Idoso , Valva Aórtica , Estudos de Avaliação como Assunto , Glutaral , Holografia , Humanos , Interferometria , Pessoa de Meia-Idade , Falha de Prótese , Preservação de Tecido
15.
J Immunol Methods ; 173(1): 55-62, 1994 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-8034986

RESUMO

We report the simultaneous use of europium-DTPA (Eu-DTPA) and samarium-DTPA (Sm-DTPA) in cytotoxicity experiments to analyze simultaneously LAK and NK cell lysis and to differentiate between specific target lysis and bystander killing. The target cells were either labelled with Eu-DTPA or Sm-DTPA chelates by electroporation, which permits the use of target cell lines or primary leukemic B cells (B-CLL) that cannot be labelled by the conventional dextran-sulphate method. The release of europium and samarium reaches a maximum at comparable time intervals (2-3 h). Due to the shorter counting interval within the samarium window the labelling efficiency is about ten times less efficient compared to europium. Using europium as label for the LAK target Daudi and samarium as label for the NK sensitive cell line K562 the differentiation of LAK versus NK activity can be performed in a single culture assay. Also, the killing of B cells and bystander cells by cytotoxic T cells was analyzed in a system where T cells were redirected to B cells through CD3 x CD19 bispecific antibodies. In fact, no bystander killing was noted when bispecific antibodies were used to bridge cytotoxic T cells to the B cells. This approach provides a simple non-radioactive method for evaluating cytotoxicity against two different cells in a single culture well.


Assuntos
Testes Imunológicos de Citotoxicidade/métodos , Európio , Samário , Linhagem Celular , Eletroporação , Európio/farmacocinética , Estudos de Avaliação como Assunto , Humanos , Técnicas In Vitro , Células Matadoras Ativadas por Linfocina/imunologia , Células Matadoras Ativadas por Linfocina/metabolismo , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Leucemia Linfocítica Crônica de Células B/imunologia , Ácido Pentético/farmacocinética , Samário/farmacocinética
16.
Biol Chem Hoppe Seyler ; 375(6): 387-92, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7980870

RESUMO

In the present work we show with different binding assays chicken gizzard myoglobin is able to bind fatty acids and bromosulphophthalein (BSP) in vitro. The fatty acid binding depends on the oxygenation of the myoglobin. Freshly prepared chicken gizzard, chicken or bovine heart myoglobin have a high fatty acid binding capability. However, when oxy-myoglobin in converted to met-myoglobin by dialysis against acidic buffer at high ionic strength (or when commercially available myoglobins are used) a 60-70% lower fatty acid binding capacity is found. Like bovine serum albumin (BSA), gizzard myoglobin has the highest affinity for unsaturated fatty acids and a lower affinity for saturated fatty acids or dyes. Chicken gizzard smooth muscle myoglobin may function as an additional fatty acid binding protein in vivo.


Assuntos
Ácidos Graxos/metabolismo , Moela das Aves/química , Mioglobina/metabolismo , Animais , Bovinos , Galinhas , Ácidos Graxos Insaturados/metabolismo , Corantes Fluorescentes , Metamioglobina/análise , Metamioglobina/metabolismo , Mioglobina/análise , Mioglobina/isolamento & purificação , Ligação Proteica , Soroalbumina Bovina/metabolismo , Espectrofotometria Infravermelho , Sulfobromoftaleína
17.
J Heart Valve Dis ; 2(3): 343-7, 1993 May.
Artigo em Inglês | MEDLINE | ID: mdl-8269130

RESUMO

Dysfunction of prosthetic heart valves is a common complication after heart valve replacement, affecting both biologic and mechanical prostheses. A preoperative, non-destructive test of each individual valve may help to prevent the implantation of a valve which has material weaknesses. To this end we developed a technique for testing heart valve prostheses by holographic interferometry. The advantage of this technique is that it provides a non-contact, non-destructive, highly sensitive three dimensional analysis of the valve under loading. Samples of several mechanical and biologic valve substitutes were investigated. Deformations of the valve, due to small pressure differences applied to the samples in a specially developed test chamber, were recorded by double exposure holography. A fringe pattern superimposed on the image of the valve reconstructed from the hologram clearly indicates the presence of even the slightest defect in the valve material. Our experimental results demonstrate the ability of non-destructive holographic screening testing to detect defects or weaknesses which may potentially lead to dysfunction in replacement valves.


Assuntos
Próteses Valvulares Cardíacas , Holografia/instrumentação , Interferometria/instrumentação , Animais , Bioprótese , Hemodinâmica/fisiologia , Humanos , Desenho de Prótese , Falha de Prótese , Controle de Qualidade , Suínos
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