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1.
Clin Radiol ; 75(12): 960.e23-960.e34, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32819705

RESUMO

The spleen is a commonly injured organ and the splenic vasculature is also susceptible to inflammation and trauma, often resulting in aneurysm formation. Splenic artery aneurysms carry a high risk of rupture and are associated with high mortality and morbidity. Due to the advances in endovascular techniques and devices, endovascular management of splenic vascular pathologies is now considered a first-line strategy. Endovascular embolisation and advance techniques including balloon- or stent-assisted coil embolisation enables minimally invasive management option while preserving splenic function.


Assuntos
Procedimentos Endovasculares , Baço/irrigação sanguínea , Esplenopatias/diagnóstico por imagem , Esplenopatias/terapia , Doenças Vasculares/diagnóstico por imagem , Doenças Vasculares/terapia , Aneurisma/diagnóstico por imagem , Aneurisma/terapia , Humanos
2.
Nat Med ; 5(2): 189-93, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9930867

RESUMO

Infection by live attenuated retroviruses provides excellent protection from challenge with pathogenic viruses in several animal models, but little is known about which immune effectors are necessary for protection. We examined this using adoptive transfer experiments in the Friend virus mouse model. Transfers of immune spleen cells into naive mice conferred complete protection, and transfers of purified lymphocyte subsets demonstrated that this effect required complex immune responses involving CD4+ and CD8+ T cells and also B cells. In addition, passive immunization experiments demonstrated that antibodies alone reduced virus loads but did not prevent infection. These findings may have implications for retroviral vaccine design in general.


Assuntos
Subpopulações de Linfócitos/imunologia , Infecções por Retroviridae/prevenção & controle , Vacinas Atenuadas/imunologia , Vacinas Virais/imunologia , Transferência Adotiva/métodos , Animais , Anticorpos Monoclonais/uso terapêutico , Anticorpos Antivirais , Feminino , Vírus da Leucemia Murina de Friend , Camundongos , Testes de Neutralização , Infecções por Retroviridae/imunologia
3.
Pain ; 14(3): 283-292, 1982 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-6760051

RESUMO

In view of several case reports of relief of various neuralgias by propranolo, a double-blind cross-over trial using this drug was conducted in 10 patients with severe persistent pain and paraesthesiae following upper limb peripheral nerve injuries. The patients received up to 240 mg of propranolol per day. Only one patient reported pain relief, but this patient withdrew from the trial. An open trial of propranolol was conducted in 6 other patients with a variety of peripheral nerve lesions. Of these, neuroma tenderness was transiently reduced in one patient and the hyperaesthesia of a painful scar was relieved in another. Routine use of propranolol in such patients cannot be recommended.


Assuntos
Traumatismos do Braço/complicações , Braço/inervação , Neuralgia/tratamento farmacológico , Traumatismos dos Nervos Periféricos , Propranolol/uso terapêutico , Adulto , Ensaios Clínicos como Assunto , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Parestesia/tratamento farmacológico , Membro Fantasma/tratamento farmacológico
4.
J Neurosurg ; 75(2): 251-5, 1991 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2072162

RESUMO

Prediction tree techniques are employed in the analysis of data from 555 patients admitted to the Medical College of Virginia hospitals with severe head injuries. Twenty-three prognostic indicators are examined to predict the distribution of 12-month outcomes among the five Glasgow Outcome Scale categories. A tree diagram, illustrating the prognostic pattern, provides critical threshold levels that split the patients into subgroups with varying degrees of risk. It is a visually useful way to look at the prognosis of head-injured patients. In previous analyses addressing this prediction problem, the same set of prognostic factors (age, motor score, and pupillary response) was used for all patients. These approaches might be considered inflexible because more informative prediction may be achieved by somewhat different combinations of factors for different patients. Tree analysis reveals that the pattern of important prognostic factors differs among various patient subgroups, although the three previously mentioned factors are still of primary importance. For example, it is noted that information concerning intracerebral lesions is useful in predicting outcome for certain patients. The overall predictive accuracy of the tree technique for these data is 77.7%, which is somewhat higher than that obtained via standard prediction methods. The predictive accuracy is highest among patients who have a good recovery or die; it is lower for patients having intermediate outcomes.


Assuntos
Traumatismos Craniocerebrais/diagnóstico , Adulto , Árvores de Decisões , Feminino , Escala de Coma de Glasgow , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico
5.
Mil Med ; 164(4): 303-5, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10226461

RESUMO

A prospective study was conducted to compare the total cost of all consumable products used to perform a general endotracheal anesthetic (GETA), a regional anesthetic, and a monitored anesthetic (MAC). For 1 month, providers completed a survey for each anesthetic rendered identifying type and quantity of consumables used. The mean cost of each type of anesthetic was identified. Analysis of variance was conducted using SPSS (version 7.5.1) to compare the mean costs of the three groups. Of 936 anesthetics performed, 536 surveys were returned (57%). The breakdown by type was GETA, 60% (N = 319); regional, 35% (N = 189); and MAC, 5% (N = 28). The mean cost per case type was GETA, $61.74; regional, $34.99; and MAC, $26.27. The cost of rendering a GETA was significantly greater (p < 0.0005) than that of either regional or MAC. Clinical practice guidelines were established to address areas in which cost savings could be realized and were provided to all anesthesia practitioners to assist in providing the safest and most cost-effective method of rendering an anesthetic.


Assuntos
Anestesia por Condução/economia , Anestesia por Inalação/economia , Custos Hospitalares , Monitorização Intraoperatória/economia , Análise de Variância , Redução de Custos , Humanos , Medicina Naval/economia , Guias de Prática Clínica como Assunto , Estudos Prospectivos
6.
J Music Ther ; 22(2): 73-86, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-10271938

RESUMO

This study compared the experiences and responsibilities of music therapy interns with requirements outlined in the Guidelines for Establishing and Maintaining Music Therapy Clinical Training Programs (National Association for Music Therapy, Inc., 1983). Subjects were 134 music therapy clinical training directors and 75 music therapy interns. Results from the intern survey indicated that over 80% of the interns were more than satisfied with their clinical training experiences. However, the data revealed several areas of concern. First, 75% of the directors and 92% of the responding interns were female; this response suggests that music therapy is not recognized as a viable career choice among male music majors. In addition, 22% of the responding clinical training facilities were not affiliated with the closest NAMT-approved college or university; reported range between these facilities and the nearest university was 5 to 1,500 miles, with a mean of 392 miles. The authors concluded that the affiliate process is often meaningless. While the Guidelines require training in "Administrative skills, i.e., budgeting, program proposals, organizational structures," nearly 63% of intern respondents had not received such training. The authors recommend that the Guidelines be rewritten and professionally printed, that interns and clinical training directors be required to complete annual questionnaires, and that the affiliation between clinical training facility and academic institution be strengthened.


Assuntos
Internato não Médico , Musicoterapia/educação , Coleta de Dados , Feminino , Humanos , Masculino , Fatores Sexuais , Estados Unidos
7.
J Music Ther ; 20(2): 88-100, 1983.
Artigo em Inglês | MEDLINE | ID: mdl-10262389

RESUMO

The stimulus for the Music/Activity Therapy Intake Assessment was a recent publication by the Joint Commission on Accreditation of Hospitals requiring for activity services, "assessment of the patient's needs, interests, life experiences, capacities, and deficiencies" (1981, p. 126). The Assessment was written in the spring of 1982 and contains four sections: Activity Preference, Organizational involvement, Attitude Survey, and Post-Interview Observations. The purpose of the present study was to investigate the psychometric properties of the Attitude Survey. The Attitude Survey was administered to 214 university students enrolled in three areas of study: human science, performance, and liberal arts. Results show that each of the three scales in the Survey is internally consistent (.63 to .74), that each scale measures a single large dimension, and that two of the three scales significantly discriminate between groups of students (p less than .05). The authors conclude that the Attitude Survey possesses adequate psychometric properties to justify its continued use as part of the Music/Activity Intake Assessment.


Assuntos
Atitude Frente a Saúde , Musicoterapia , Análise Fatorial , Hospitais Psiquiátricos , Humanos , Psicometria , Estados Unidos
8.
Percept Mot Skills ; 50(1): 225-6, 1980 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7367172

RESUMO

It was hypothesized that the large variance in low achievers' self-portraits may be related to frustration and symbolic acting out. 29 low achievers in Reading and Mathematics were given the Describe Your School inventory. Subjects below the median drew pictures which were taller than pictures drawn by subjects above the median score. It was concluded that frustation must be considered when using height of drawing to analyze low achievers' self-portraits.


Assuntos
Estatura , Imagem Corporal , Frustração , Baixo Rendimento Escolar , Encenação , Criança , Feminino , Humanos , Masculino , Leitura
9.
Australas Radiol ; 51(2): 182-5, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17419868

RESUMO

Knotting of intravascular catheters is an uncommon but a well-recognized occurrence. The Swan-Ganz catheter (SGC) is the one that knots most commonly. A case of a knotted SGC is described in a patient with a persistent left-sided superior vena cava, and we propose that the presence of a left-sided superior vena cava is a risk factor for knot formation not previously reported. We review the published work on the risk factors for knot formation and on the techniques used to remove knotted SGC. We describe a technique using a gooseneck snare and Omni Flush catheter (Angiodynamics, Queensbury, NY, USA) to loosen and untie a knotted SGC.


Assuntos
Cateterismo de Swan-Ganz/efeitos adversos , Corpos Estranhos/terapia , Veia Cava Superior/anormalidades , Adulto , Remoção de Dispositivo , Feminino , Corpos Estranhos/diagnóstico por imagem , Humanos , Radiografia , Veia Cava Superior/diagnóstico por imagem
10.
CRNA ; 11(2): 62-5, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-11271041

RESUMO

The psoas compartment acts as a conduit for the nerve roots of the lumbar plexus. Originating at approximately the 12th thoracic vertebrae, this potential compartment continues on caudally, bordered posterolaterally by fascia of the quadratus lumborum and iliacus muscles, medially by the fascia of the psoas major muscle, and anteriorly by the transversalis fascia. This natural "gutter" acts as a repository for local anesthetic agents and provides an excellent method of unilateral anterior lower extremity anesthesia. After elicitation of a motor evoked response in the muscles of the anterior thigh, 30 to 40 milliliters of local anesthetic is incrementally injected into the compartment. Spread of the anesthetic to all roots of the plexus occurs in 15 to 20 minutes. Profound sensory and motor blockade can be achieved providing surgical anesthesia as well as long duration postoperative pain relief.


Assuntos
Plexo Lombossacral/anatomia & histologia , Bloqueio Nervoso/métodos , Músculos Psoas , Humanos , Enfermeiros Anestesistas
11.
Blood ; 82(11): 3327-32, 1993 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-8241503

RESUMO

The cell surface molecule Ly-6A/E provides a convenient marker for primitive stem cells in the hematopoietic tissues of both fetal and adult mice. However, previous studies have shown that Ly-6A/E expression by lymphocytes is variable depending on the haplotype of the Ly-6 locus. Therefore, strain-specific variation in Ly-6A/E expression by bone marrow (BM) cells was investigated. The results show that Ly-6a mice have, on average, 50% of the number of BM cells expressing Ly-6A/E relative to that for Ly-6b mice. Furthermore, among the 5% of BM cells that do not express antigens characteristic of mature T, B, myeloid, or erythroid lineages, which include the primitive hematopoietic stem cell compartment, Ly-6a mice have, on average, more than fivefold fewer Ly-6A/E+ cells relative to that for Ly-6b mice. Isolation of Ly-6A/E- and Ly-6A/E+ cells from mice of both haplotypes showed that, whereas 99% of the marrow repopulating activity (MRA) of C57BL/Ka (Ly-6b) mice could be recovered in the Ly-6A/E+ fraction, only about 25% of the MRA of BALB/c (Ly-6a) was recoverable in the same population. On a per-cell basis, the Ly-6A/E+ cells that were isolated from BALB/c mice were essentially equivalent in MRA to those isolated from C57BL/Ka mice. Thus, whereas a large percentage of the hematopoietic stem cells of Ly-6a mice do not express the Ly-6A/E molecule, the antigen may be used to isolate a subset of stem cells from these mice. These results show that hematopoietic stem cell phenotype can vary between mouse strains and imply that caution should be exercised in the identification of human stem cell antigens such as CD34, because a similar variability may occur between individual humans. To further explore the influence of Ly-6 haplotype on Ly-6A/E expression by specific cell subsets, lymph-node lymphocytes from a panel of mouse strains were analyzed by multiparameter flow cytometry for correlated expression of Ly-6A/E, CD4, and CD8. All Ly-6a strains examined had less than 20% Ly-6A/E+ cells, and those cells were predominantly CD8+ T lymphocytes. In contrast, the Ly-6b strains had greater than 30% Ly-6A/E+ cells, and those cells included CD4+, CD8+, and B lymphocytes.


Assuntos
Antígenos Ly/análise , Medula Óssea/imunologia , Células-Tronco Hematopoéticas/imunologia , Animais , Camundongos , Camundongos Endogâmicos , Especificidade da Espécie , Subpopulações de Linfócitos T/imunologia
12.
Hand ; 10(1): 61-4, 1978 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-710984

RESUMO

Nerve pedicle grafts in the upper limb were performed on nine patients with Volkmann's Ischaemia. Long-term follow-up of three cases has shown that the results of this operation are successful. Sensory and motor recovery of the median nerve occurs and consequently useful hand function is regained. Since Volkmann's Ischaemic contracture is not rare in developing countries, this operation should be the treatment of choice when the median and ulnar nerves have been damaged beyond hope of recovery.


Assuntos
Síndromes Compartimentais/cirurgia , Nervo Mediano/cirurgia , Nervo Ulnar/transplante , Adulto , Braço/cirurgia , Criança , Seguimentos , Humanos
13.
Blood ; 80(8): 1957-64, 1992 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-1356513

RESUMO

Mouse hematopoietic stem cells can be identified and enriched from populations of normal bone marrow cells by immunofluorescent labeling of cell surface molecules followed by flow cytometric separation. We show here that the majority of hematopoietic stem cell activity, as defined by long-term competitive repopulation of irradiated animals and by a secondary transplant assay for spleen colony-forming units (CFU-S), could be localized in Ly-6b haplotype mice to a fraction of bone marrow cells that expresses the Ly-6A/E (Sca-1) molecule. Further, an analysis of hematopoietic stem cell activity in bone marrow of mouse strains expressing the Thy-1.1 allele indicated that the vast majority of activity was included in the Thy-1low population. In contrast, hematopoietic stem cell activity found in the bone marrow of Thy-1.2 genotype mouse strains was recovered in both the Thy-1neg and the Thy-1low populations. However, similar to Thy-1.1 strains, most activity was localized to the Ly-6A/E+ population of cells. The difference in Thy-1 phenotype of hematopoietic stem cell activity apparent between Thy-1.1- and Thy-1.2-expressing mouse strains was not caused by differences in the staining intensity of monoclonal antibodies (MoAbs) specific for the Thy-1 alleles. Furthermore, an antiframework MoAb that stains both alleles of Thy-1 separated hematopoietic stem cell activity from mice expressing the two alleles in the same manner as did allele-specific MoAb. The results of this study show that Thy-1 expression is not an invariant characteristic of mouse hematopoietic stem cells, and that mice expressing the Thy-1.1 allele are unique in that hematopoietic stem cell activity is found exclusively in the Thy-1low population.


Assuntos
Antígenos de Superfície/análise , Células-Tronco Hematopoéticas/imunologia , Imunofenotipagem , Glicoproteínas de Membrana/análise , Animais , Anticorpos Monoclonais , Antígenos Ly/análise , Transplante de Medula Óssea , Separação Celular , Ensaio de Unidades Formadoras de Colônias , Citometria de Fluxo , Hematopoese/fisiologia , Células-Tronco Hematopoéticas/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Antígenos Thy-1
14.
Mol Plant Pathol ; 1(2): 139-50, 2000 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-20572960

RESUMO

Abstract To identify virulence genes of P. syringae pv. tomato strain DC3000 we screened for mutants with reduced virulence on its plant hosts, Arabidopsis thaliana and tomato. We isolated a Tn5-insertion mutant that exhibited reduced virulence on both hosts. Further characterization showed that this mutant carried a single Tn5 insertion in the dsbA gene, which encodes a periplasmic disulphide bond-forming protein. In addition to reduced virulence, the dsbA mutant exhibits mucoid colony morphology, loss of fluorescence, decreased motility, and a reduced growth rate in culture. The dsbA mutant is able to multiply in A. thaliana and tomato plants, trigger the hypersensitive response on tobacco and elicit Pto-mediated resistance in tomato, indicating that type III secretion occurs in this background. However, type III secretion appears to function with reduced efficiency in the dsbA mutant, as type III-dependent secretion of HrpZ and AvrRpt2 is impaired. These findings indicate that while the dsbA gene is required for multiple cellular functions in P. syringae, type III secretion in P. syringae is only partially dependent on dsbA.

15.
J Mol Evol ; 21(2): 133-8, 1984.
Artigo em Inglês | MEDLINE | ID: mdl-6442989

RESUMO

We compared the homologous amino acid sequences of hevein and each of the four domains (A, B, C, and D) of wheat germ agglutinin and used them to construct a pseudophylogenetic tree relating these sequences to a hypothetical common ancestor sequence. In the crystal structure of the wheat germ agglutinin dimer, six pseudo-two-fold rotational symmetry axes have previously been located in addition to the true twofold axis. Four of these relate two nonidentical domains to each other in each of the four possible pairs constituting the sugar-binding sites (A1D2, A2D1, B1C2, and B2C1). The remaining two relate contiguous unique pairs of sugar-binding sites to each other (A1D2 to B1C2, and A2D1 to B2C1). These latter two sets of pairs are related to each other by the true twofold axis. Side chains that mediate sugar binding in the interfaces of each of the four pairs were found to be largely conserved. The sequence homology, taken together with these pseudo-symmetry elements in the dimer structure, suggests a pathway for the evolution of the four-domain molecule from a single-domain dimer that can be correlated with simultaneous development of the saccharide-binding sites.


Assuntos
Peptídeos Catiônicos Antimicrobianos , Evolução Biológica , Lectinas , Proteínas de Plantas , Sequência de Aminoácidos , Sequência de Bases , Sítios de Ligação , Dissulfetos , Filogenia , Lectinas de Plantas , Conformação Proteica , Relação Estrutura-Atividade , Triticum , Aglutininas do Germe de Trigo
16.
J Virol ; 72(8): 6554-8, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9658099

RESUMO

Live-attenuated retroviruses have been shown to be effective retroviral vaccines, but currently little is known regarding the mechanisms of protection. In the present studies, we used Friend virus as a model to analyze characteristics of a live-attenuated vaccine in protection against virus-induced disease. Highly susceptible mice were immunized with nonpathogenic Friend murine leukemia helper virus (F-MuLV), which replicates poorly in adult mice. Further attenuation of the vaccine virus was achieved by crossing the Fv-1 genetic resistance barrier. The minimum dose of vaccine virus required to protect 100% of the mice against challenge with pathogenic Friend virus complex was determined to be 10(3) focus-forming units of attenuated virus. Live vaccine virus was necessary for induction of immunity, since inactivated F-MuLV did not induce protection. To determine whether immune cells mediated protection, spleen cells from vaccinated donor mice were adoptively transferred into syngeneic recipients. The results indicated that immune mechanisms rather than viral interference mediated protection.


Assuntos
Vírus da Leucemia Murina de Friend/imunologia , Leucemia Experimental/prevenção & controle , Infecções por Retroviridae/prevenção & controle , Infecções Tumorais por Vírus/prevenção & controle , Vacinas Virais/imunologia , Animais , Anticorpos Antivirais/imunologia , Leucemia Experimental/imunologia , Camundongos , Testes de Neutralização , Infecções por Retroviridae/imunologia , Baço/citologia , Baço/imunologia , Infecções Tumorais por Vírus/imunologia , Vacinação , Vacinas Atenuadas/imunologia , Viremia/imunologia , Viremia/prevenção & controle
17.
J Virol ; 72(8): 6559-64, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9658100

RESUMO

Reactivations of persistent viral infections pose a significant medical problem in immunocompromised cancer, transplant, and AIDS patients, yet little is known about how persistent viral infections are immunologically controlled. Here we describe a mouse model for investigating the role of the immune response in controlling a persistent retroviral infection. We demonstrate that, following recovery from acute Friend virus infection, a small number of B cells evade immunological destruction and harbor persistent virus. In vivo depletions of T-cell subsets in persistently infected mice revealed a critical role for CD4(+) T cells in controlling virus replication, spread to the erythroid lineage, and induction of erythroleukemia. The CD4(+) T-cell effect was independent of CD8(+) T cells and in some cases was also independent of virus-neutralizing antibody responses. Thus, the CD4(+) T cells may have had a direct antiviral effect. These results may have relevance for human immunodeficiency virus (HIV) infections where loss of CD4(+) T cells is associated with an increase in HIV replication, reactivation of persistent viruses, and a high incidence of virus-associated cancers.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Vírus da Leucemia Murina de Friend/imunologia , Leucemia Experimental/imunologia , Infecções por Retroviridae/imunologia , Infecções Tumorais por Vírus/imunologia , Animais , Linfócitos B/virologia , Linfócitos T CD8-Positivos/imunologia , Feminino , Vírus da Leucemia Murina de Friend/fisiologia , Leucemia Eritroblástica Aguda , Leucemia Experimental/virologia , Depleção Linfocítica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Infecções por Retroviridae/virologia , Esplenomegalia , Infecções Tumorais por Vírus/virologia , Latência Viral , Replicação Viral
18.
Proc Natl Acad Sci U S A ; 92(23): 10492-5, 1995 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-7479826

RESUMO

Administration of virus-specific antibodies is known to be an effective early treatment for some viral infections. Such immunotherapy probably acts by antibody-mediated neutralization of viral infectivity and is often thought to function independently of T-cell-mediated immune responses. In the present experiments, we studied passive antibody therapy using Friend murine leukemia virus complex as a model for an immunosuppressive retroviral disease in adult mice. The results showed that antibody therapy could induce recovery from a well-established retroviral infection. However, the success of therapy was dependent on the presence of both CD4+ and CD8+ T lymphocytes. Thus, cell-mediated responses were required for recovery from infection even in the presence of therapeutic levels of antibody. The major histocompatibility type of the mice was also an important factor determining the relative success of antibody therapy in this system, but it was less critical for low-dose than for high-dose infections. Our results imply that limited T-cell responsiveness as dictated by major histocompatibility genes and/or stage of disease may have contributed to previous immunotherapy failures in AIDS patients. Possible strategies to improve the efficacy of future therapies are discussed.


Assuntos
Vírus da Leucemia Murina de Friend , Imunoterapia Adotiva , Complexo Principal de Histocompatibilidade , Infecções por Retroviridae/terapia , Linfócitos T/imunologia , Síndrome da Imunodeficiência Adquirida/terapia , Animais , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Feminino , Depleção Linfocítica , Camundongos , Análise de Sobrevida
19.
ASAIO Trans ; 37(3): M203-4, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1751111

RESUMO

A new transintegumental power transformer uses the walls of an isolated intestinal pouch to separate primary and secondary coils. It may surpass transcutaneous devices in heat dissipation potential and in comfort. It was acutely tested in 13 dogs. Corrections in geometry and insulation were suggested by the nine initial trials. In the remaining four animals, up to 14.1 W were delivered, incrementing over 90 to 395 min. Three pouch and two remote thermistors recorded temperature (T) at 10 min intervals. Thirty sets of data were taken at 4 W or less (Group A), 31 at 4-8 W (Group B), and 16 at more than 8 W (Group C). T elevations above reference drift were 0.096 + 0.062 degrees C, 0.468 + 0.234 degrees C, and 0.876 + 0.156 degrees C for groups A, B, and C, respectively. These were significant by t-tests (p less than 0.001 for Group A vs. B; p less than 0.05 for Group B vs. C). The concept appears to be feasible, and longer term implantation trials seem justified.


Assuntos
Fontes de Energia Elétrica , Coração Auxiliar , Ileostomia , Animais , Cães , Condutividade Elétrica , Transferência de Energia
20.
Clin Infect Dis ; 25 Suppl 1: S2-8, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9233657

RESUMO

Lyme disease is a persistent low-density spirochetosis caused by Borrelia burgdorferi sensu lato. Although spirochetes causing Lyme disease are highly immunogenic in experimental models, the onset of specific antibody responses to infection is often delayed or undetectable in some patients. The properties and mechanisms mediating such immune avoidance remain obscure. To examine the nature and consequences of interactions between Lyme disease spirochetes and immune effector cells, we coincubated B. burgdorferi with primary and cultured human leukocytes. We found that B. burgdorferi actively attaches to, invades, and kills human B and T lymphocytes. Significant killing began within 1 hour of mixing. Cytopathic effects varied with respect to host cell lineage and the species, viability, and degree of attenuation of the spirochetes. Both spirochetal virulence and lymphocytic susceptibility could be phenotypically selected, thus indicating that both bacterial and host cell factors contribute to such interactions. These results suggest that invasion and lysis of lymphocytes may constitute previously unrecognized factors in Lyme disease and bacterial pathogenesis.


Assuntos
Grupo Borrelia Burgdorferi/patogenicidade , Doença de Lyme/microbiologia , Linfócitos/microbiologia , Linfócitos B/microbiologia , Aderência Bacteriana , Borrelia/patogenicidade , Grupo Borrelia Burgdorferi/metabolismo , Células Cultivadas , Humanos , Linfócitos/metabolismo , Linfócitos T/microbiologia
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