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1.
Pediatr Cardiol ; 43(8): 1857-1863, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35536424

RESUMO

Supraventricular tachycardia (SVT) is a common pediatric arrhythmia. The objective of this investigation was to investigate the existence and degree of the health disparities in the treatment of pediatric patients with supraventricular tachycardia based on sociodemographic factors. This was retrospective cohort study at a large academic medical center including children ages 5-18 years old diagnosed with SVT. Patients with congenital heart disease and myocarditis were excluded. Initial treatment and ultimate treatment with either medical management or ablation were determined. The odds of having an ablation procedure were determined based on patient age, sex, race, ethnicity, and insurance status. There was a larger portion of non-White patients (p = 0.033) within the cohort that did not receive an ablation during the study period. Patients that were younger, female, American Indian/Alaskan Native, unknown race, and had missing insurance information were less likely to receive ablation therapy during the study period. In this single center, regional evaluation, we demonstrated that disparities in the treatment of pediatric SVT are present based on multiple patient sociodemographic factors. This study adds evidence to the presence of inequities in health care delivery across pediatric populations.


Assuntos
Ablação por Cateter , Cardiopatias Congênitas , Taquicardia Supraventricular , Criança , Humanos , Feminino , Pré-Escolar , Adolescente , Estudos Retrospectivos , Ablação por Cateter/métodos , Resultado do Tratamento , Taquicardia Supraventricular/cirurgia , Taquicardia Supraventricular/diagnóstico , Cardiopatias Congênitas/cirurgia
2.
Phys Rev Lett ; 127(2): 025002, 2021 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-34296928

RESUMO

The key result of the present work is the theoretical prediction and observation of the formation of a new type of transport barrier in fusion plasmas, called F-ATB (fast ion-induced anomalous transport barrier). As demonstrated through state-of-the-art global electrostatic and electromagnetic simulations, the F-ATB is characterized by a full suppression of the turbulent transport-caused by strongly sheared, axisymmetric E×B flows-and an increase of the neoclassical counterpart, albeit keeping the overall fluxes at significantly reduced levels. The trigger mechanism is shown to be a mainly electrostatic resonant interaction between suprathermal particles, generated via ion-cyclotron-resonance heating, and plasma microturbulence. These findings are obtained by realistic simulations of the ASDEX Upgrade discharge No. 36637-properly designed to maximized the beneficial role of the wave-particle resonance interaction-which exhibits the expected properties of improved confinement produced by energetic particles.

3.
Curr Cardiol Rep ; 22(1): 5, 2020 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-31950297

RESUMO

PURPOSE OF REVIEW: Pacing in pediatric and adult patients with congenital heart disease requires careful evaluation and thoughtful planning. Review of current guidelines with assessment of risk/benefit must be performed along with planning on a case-by-case basis in order to achieve maximal success and reduce risk in this specialized population of patients that is rapidly increasing in size. RECENT FINDINGS: Guidelines for pacing in pediatric and congenital heart disease patients span many years. Most recent consensus and summary guidelines address pacing in adult patients with or without congenital heart disease. Pediatric recommendations from prior documents must be included in current decision-making. Pacing in pediatric and congenital heart disease patients is important therapy. Creation of an individualized plan of care with attention to risk/benefit decision-making regarding when and how to pace is critical in this population to maximize beneficial outcome.


Assuntos
Estimulação Cardíaca Artificial/métodos , Cardiopatias Congênitas/cirurgia , Insuficiência Cardíaca/prevenção & controle , Adulto , Criança , Consenso , Humanos , Guias de Prática Clínica como Assunto , Fatores de Tempo
4.
Ann Bot ; 122(5): 747-756, 2018 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-29236942

RESUMO

Background and Aims: Anaesthesia for medical purposes was introduced in the 19th century. However, the physiological mode of anaesthetic drug actions on the nervous system remains unclear. One of the remaining questions is how these different compounds, with no structural similarities and even chemically inert elements such as the noble gas xenon, act as anaesthetic agents inducing loss of consciousness. The main goal here was to determine if anaesthetics affect the same or similar processes in plants as in animals and humans. Methods: A single-lens reflex camera was used to follow organ movements in plants before, during and after recovery from exposure to diverse anaesthetics. Confocal microscopy was used to analyse endocytic vesicle trafficking. Electrical signals were recorded using a surface AgCl electrode. Key Results: Mimosa leaves, pea tendrils, Venus flytraps and sundew traps all lost both their autonomous and touch-induced movements after exposure to anaesthetics. In Venus flytrap, this was shown to be due to the loss of action potentials under diethyl ether anaesthesia. The same concentration of diethyl ether immobilized pea tendrils. Anaesthetics also impeded seed germination and chlorophyll accumulation in cress seedlings. Endocytic vesicle recycling and reactive oxygen species (ROS) balance, as observed in intact Arabidopsis root apex cells, were also affected by all anaesthetics tested. Conclusions: Plants are sensitive to several anaesthetics that have no structural similarities. As in animals and humans, anaesthetics used at appropriate concentrations block action potentials and immobilize organs via effects on action potentials, endocytic vesicle recycling and ROS homeostasis. Plants emerge as ideal model objects to study general questions related to anaesthesia, as well as to serve as a suitable test system for human anaesthesia.


Assuntos
Anestésicos/efeitos adversos , Éter/efeitos adversos , Homeostase , Magnoliopsida/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Potenciais de Ação/efeitos dos fármacos , Potenciais de Ação/fisiologia , Arabidopsis/efeitos dos fármacos , Arabidopsis/fisiologia , Clorofila/metabolismo , Drosera/efeitos dos fármacos , Drosera/fisiologia , Droseraceae/efeitos dos fármacos , Droseraceae/fisiologia , Germinação/efeitos dos fármacos , Lepidium sativum/efeitos dos fármacos , Lepidium sativum/fisiologia , Magnoliopsida/fisiologia , Mimosa/efeitos dos fármacos , Mimosa/fisiologia , Organelas/efeitos dos fármacos , Organelas/fisiologia , Pisum sativum/efeitos dos fármacos , Pisum sativum/fisiologia , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/fisiologia , Vesículas Transportadoras/efeitos dos fármacos , Vesículas Transportadoras/fisiologia
5.
Cardiol Young ; 28(3): 485-489, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29233209

RESUMO

Cardiac rhabdomyomas are the most common tumours in children and are typically seen in association with the tuberous sclerosis complex. Although benign and often associated with spontaneous regression, in rare circumstances surgical resection is indicated to relieve obstruction or other mass-related effects. Recent clinical trials have demonstrated the benefits of mammalian target of rapamycin inhibitors for the treatment of other tumour sub-types associated with tuberous sclerosis. Here we report rapid regression of several massive cardiac rhadomyomas in two neonates with the use of the mammalian target of rapamycin inhibitor sirolimus.


Assuntos
Neoplasias Cardíacas/tratamento farmacológico , Rabdomioma/tratamento farmacológico , Sirolimo/uso terapêutico , Ecocardiografia , Neoplasias Cardíacas/diagnóstico por imagem , Humanos , Recém-Nascido , Rabdomioma/diagnóstico por imagem , Esclerose Tuberosa/complicações
6.
Genes Immun ; 15(1): 57-61, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24285176

RESUMO

Langerhans cells (LCs) are bone marrow-derived immature skin-residential dendritic cells (DCs) with a life cycle distinct from that of other types of DCs. The mechanisms involved in LC homeostasis and immunological functions are still not clear. MicroRNAs (miRNAs) are a class of short noncoding RNAs that regulate gene expression through either translational repression or mRNA degradation. A recent study showed that specific deletion of total miRNAs in DCs affects the homeostasis and function of only LCs, but not of other types of DCs. The roles of specific individual miRNA in LC development are still lacking. The miRNA miR-17-92 class, encoding miR-17, miR-18, miR-19a, miR-19b, miR-20 and miR-92, plays a very important role in B- and T-cell development and function. Here, we first report that epidermal LCs highly express the miR-17-92 class compared with spleen naive T cells. To further characterize the role of miR-17-92 in LC development, we generated LC-specific miR-17-92 knockout and knock-in mice. Interestingly, LC-specific gain- and loss-of-function of miR-17-92 cluster did not significantly change LC homeostasis, maturation ability, antigen capture and migration to draining lymph nodes. Thus, the miR-17-92 cluster may be functionally redundant and not critically required for LC development and function.


Assuntos
Células de Langerhans/fisiologia , MicroRNAs/genética , Animais , Movimento Celular , Dermatite Alérgica de Contato/genética , Dermatite Alérgica de Contato/imunologia , Dinitrofluorbenzeno/imunologia , Dinitrofluorbenzeno/toxicidade , Células Epidérmicas , Regulação da Expressão Gênica , Homeostase , Camundongos , Camundongos Knockout , Família Multigênica , Baço/citologia , Linfócitos T/fisiologia
7.
Gut ; 58(4): 560-9, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18689426

RESUMO

BACKGROUND: Hepatitis C virus (HCV) effectively establishes persistent infection in human livers. The non-structural (NS) 3/4A complex participates in this process by cleavage of interferon beta (IFN beta) promoter stimulator-1 (IPS-1; also termed Cardif/MAVS/VISA), which inhibits responses to double stranded (ds) RNA. However, it is not known whether this effect extends beyond innate responses. AIMS: To test if HCV NS3/4A affects innate and adaptive immune responses in vivo. METHODS: NS3 levels were semi-quantified in human liver biopsies, transfected cells, and in transgenic (Tg) mouse livers by western blot. The effect of NS3/4A on dsRNA-mediated signalling and on the integrity of IPS-1 was analysed using in vitro translation, transfected cells and Tg mice. Cytotoxic T cell (CTL)-mediated clearance of transient firefly luciferase (FLuc)- and/or NS3/4A-Tg hepatocytes was determined using in vivo imaging and western blot. RESULTS: NS3 protein levels were in a comparable range (0.1-49 microg/g tissue) in infected human livers and Tg mouse livers. Importantly, these levels of NS3/4A reduced murine innate responses to synthetic dsRNA in vivo, supporting the possibility that this occurs also in infected humans. The likely explanation for this was the NS3/4A-mediated cleavage of mouse IPS-1, albeit less efficiently than human IPS-1. Despite this, FLuc- and/or NS3/4A-expressing murine hepatocytes were effectively eliminated by hepatic CTLs, utilising the classical molecules for virus-infected cell lysis, including CD8, IFN gamma, perforin and FasL. CONCLUSIONS: Although HCV NS3/4A inhibits the innate immunity, this does not prevent CTL-mediated clearance of NS3/4A-expressing hepatocytes in vivo. Thus, other HCV proteins are most likely responsible for interfering with the adaptive immunity.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/imunologia , Hepacivirus , Hepatite C Crônica/imunologia , Hepatócitos/virologia , Linfócitos T/imunologia , Proteínas não Estruturais Virais/metabolismo , Animais , Modelos Animais de Doenças , Feminino , Hepacivirus/imunologia , Hepacivirus/metabolismo , Hepatite C Crônica/virologia , Hepatócitos/imunologia , Humanos , Imunidade Inata , Interferon beta/imunologia , Fígado/metabolismo , Neoplasias Hepáticas/imunologia , Masculino , Camundongos , Camundongos Endogâmicos , Camundongos Transgênicos , NF-kappa B/metabolismo , RNA de Cadeia Dupla/imunologia , Especificidade da Espécie , Células Tumorais Cultivadas
8.
Ned Tijdschr Geneeskd ; 1642020 02 03.
Artigo em Holandês | MEDLINE | ID: mdl-32186813

RESUMO

BACKGROUND: Vertigo is a common complaint and may rarely be the presenting symptom of a paraneoplastic neurological syndrome (PNS). CASE DESCRIPTION: A 76-year-old woman presented at the ER with subacute cerebellar syndrome and severe vertigo. Laboratory testing revealed mild anaemia. A cerebral CT scan showed no intracranial pathology. The patient was admitted for observation. History-taking revealed she been suffering from general malaise and had unintentionally lost 16 kg in weight over recent months. Further PET-CT investigations revealed multiple enlarged mediastinal and abdominal lymph nodes with high metabolic activity. Histopathological investigation of a lymph node biopsy showed a malignancy originating from the genital tract. Positive anti-neuronal antibodies (anti-Yo) and an elevated CA-125 concentration were found in peripheral blood. We diagnosed paraneoplastic cerebellar degeneration as the first manifestation of hitherto undiagnosed occult ovarian cancer. CONCLUSION: In a patient with subacute, cerebellar syndrome with severe vertigo, after ruling out other causes, the diagnosis of PNS should be considered. Determination of anti-neuronal antibodies can help in the diagnosis. Early recognition of PNS is important for the diagnosis and treatment of the underlying malignancy.


Assuntos
Neoplasias Ovarianas/diagnóstico , Degeneração Paraneoplásica Cerebelar/diagnóstico , Vertigem/diagnóstico , Idoso , Diagnóstico Diferencial , Feminino , Humanos , Neoplasias Ovarianas/complicações , Degeneração Paraneoplásica Cerebelar/complicações , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Vertigem/etiologia
9.
Rev Sci Instrum ; 89(10): 10J101, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30399687

RESUMO

The B-dot probe diagnostic suite on the ASDEX Upgrade tokamak has recently been upgraded with a new 125 MHz, 14 bit resolution digitizer to study ion cyclotron emission (ICE). While classic edge emission from the low field side plasma is often observed, we also measure waves originating from the core with fast fusion protons or beam injected deuterons being a possible emission driver. Comparing the measured frequency values with ion cyclotron harmonics present in the plasma places the origin of this emission on the magnetic axis, with the fundamental hydrogen/second deuterium cyclotron harmonic matching the observed values. The actual values range from ∼27 MHz at the on-axis toroidal field BT = -1.79 T to ∼40 MHz at BT = -2.62 T. When the magnetic axis position evolves during this emission, the measured frequency values track the changes in the estimated on-axis cyclotron frequency values. Core ICE is usually a transient event lasting ∼100 ms during the neutral beam startup phase. However, in some cases, core emission occurs in steady-state plasmas and lasts for longer than 1 s. These observations suggest an attractive possibility of using a non-perturbing ICE-based diagnostic to passively monitor fusion alpha particles at the location of their birth in the plasma core, in deuterium-tritium burning devices such as ITER and DEMO.

10.
Gut ; 55(10): 1475-83, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16527836

RESUMO

BACKGROUND: The hepatitis C virus (HCV) establishes chronic infection by incompletely understood mechanisms. The non-structural (NS) 3/4A protease/helicase has been proposed as a key complex in modulating the infected hepatocyte, although nothing is known about the effects this complex exerts in vivo. AIM: To generate mice with stable and transient hepatocyte expression of the HCV NS3/4A proteins to study its effects in vivo. METHODS: NS3/4A expression was determined by western blot and immunohistochemistry. Two independent pathologists determined the liver histology. Hepatic immunity was characterised by quantifying intrahepatic immune cell subsets. Liver damage was induced using carbon tetrachloride (CCl(4)), lipopolysaccaride (LPS), tumour necrosis factor alpha (TNFalpha), and anti-Fas antibody. RESULTS: Expression of NS3/4A was restricted to the cytoplasm of hepatocytes, and did not cause liver cancer or any spontaneous liver pathology. However, the presence of NS3/4A modulated the intrahepatic immunity, as follows: first, the CD4+ T cell and type I/II dendritic cell subsets were reduced in transgenic livers; second, NS3/4A protected hepatocytes from liver damage mediated in vivo by CCl(4), LPS, TNFalpha, but not FAS; and third, both stable and transiently NS3/4A transgenic mice were resistant to lethal doses of liver targeted TNFalpha, and the resistance could be reverted by treatment with a p38 mitogen activated protein kinase inhibitor (MAPK). CONCLUSIONS: Hepatic expression of NS3/4A does not induce spontaneous liver disease. NS3/4A does, however, alter the intrahepatic immune cell subsets and protects hepatocytes against TNFalpha induced liver damage in vivo. The TNFalpha resistance can be reverted by treatment with a p38 MAPK inhibitor. This represents a new immune evasion strategy conferred by NS3/4A.


Assuntos
Hepacivirus/imunologia , Hepatopatias/imunologia , Fator de Necrose Tumoral alfa/imunologia , Animais , Hepatócitos/metabolismo , Imuno-Histoquímica , Subpopulações de Linfócitos/imunologia , Camundongos , Camundongos Transgênicos , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores
12.
Sci Rep ; 7: 42999, 2017 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-28220850

RESUMO

Acoustic telemetry is one of the primary technologies for studying the behavior and survival of fishes throughout the world. The size and performance of the transmitter are key limiting factors. The newly developed injectable transmitter is the first acoustic transmitter that can be implanted via injection instead of surgery. A two-part field study was conducted to evaluate the performance of the injectable transmitter and its effect on the survival of implanted fish. The injectable transmitter performed well and similarly to the proceeding generation of commercially-available JSATS transmitters tested concurrently. Snake River subyearling Chinook salmon smolts implanted with the injectable transmitter had a higher survival probability from release to each of eleven downstream detection arrays, because reach-specific survival estimates were significantly higher for the injectable group in three of the eleven reaches examined. Overall, the injectable group had a 0.263 (SE = 0.017) survival probability over the entire 500 km study area compared to 0.199 (0.012) for the surgically implanted group. The reduction in size and ability to implant the new transmitter via injection has reduced the tag or tagging effect bias associated with studying small fishes. The information gathered with this new technology is helping to evaluate the impacts of dams on fishes.


Assuntos
Salmão/fisiologia , Telemetria/métodos , Acústica , Migração Animal , Animais , Rios , Telemetria/instrumentação
14.
Rev Sci Instrum ; 86(7): 073508, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26233384

RESUMO

At ASDEX Upgrade (AUG), a new compact solid-state detector has been installed to measure the energy spectrum of fast neutrals based on the principle described by Shinohara et al. [Rev. Sci. Instrum. 75, 3640 (2004)]. The diagnostic relies on the usual charge exchange of supra-thermal fast-ions with neutrals in the plasma. Therefore, the measured energy spectra directly correspond to those of confined fast-ions with a pitch angle defined by the line of sight of the detector. Experiments in AUG showed the good signal to noise characteristics of the detector. It is energy calibrated and can measure energies of 40-200 keV with count rates of up to 140 kcps. The detector has an active view on one of the heating beams. The heating beam increases the neutral density locally; thereby, information about the central fast-ion velocity distribution is obtained. The measured fluxes are modeled with a newly developed module for the 3D Monte Carlo code F90FIDASIM [Geiger et al., Plasma Phys. Controlled Fusion 53, 65010 (2011)]. The modeling allows to distinguish between the active (beam) and passive contributions to the signal. Thereby, the birth profile of the measured fast neutrals can be reconstructed. This model reproduces the measured energy spectra with good accuracy when the passive contribution is taken into account.

15.
Sci Rep ; 5: 8111, 2015 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-25630763

RESUMO

Salmon recovery and the potential detrimental effects of dams on fish have been attracting national attention due to the environmental and economic implications. In recent years acoustic telemetry has been the primary method for studying salmon passage. However, the size of the existing transmitters limits the minimum size of fish that can be studied, introducing a bias to the study results. We developed the first acoustic fish transmitter that can be implanted by injection instead of surgery. The new injectable transmitter lasts four times longer and weighs 30% less than other transmitters. Because the new transmitter costs significantly less to use and may substantially reduce adverse effects of implantation and tag burden, it will allow for study of migration behavior and survival of species and sizes of fish that have never been studied before. The new technology will lead to critical information needed for salmon recovery and the development of fish-friendly hydroelectric systems.


Assuntos
Acústica/instrumentação , Salmão/fisiologia , Telemetria/instrumentação , Animais , Desenho de Equipamento , Injeções
16.
J Immunol Methods ; 191(2): 159-70, 1996 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-8666835

RESUMO

Conductive polymers are extensively conjugated macromolecules able to conduct electricity in their doped state and having a UV-visible spectrum which undergoes important chromatic modifications when subjected to pH changes or to oxido-reductive processes. This article describes a novel homogeneous immunoassay in which a water-soluble conductive polymer is used as the label. When antigen-antibody binding occurs, the local pH near the complex is modified. Such a pH change is in turn able to induce modifications in the absorbance at a characteristic wavelength of a conductive polymer covalently linked to either the antigen or the antibody. Consequently, the extent of tracer binding can be directly monitored by photometry during incubation. We present examples which validate the concept and exemplify its applicability in quantitative competitive immunoassays for human C-reactive protein and human serum albumin, as performed in a Cobas-Mira automated analyzer.


Assuntos
Autoanálise/métodos , Imunoensaio/métodos , Polímeros/química , Água/química , Albuminúria , Sítios de Ligação de Anticorpos , Ligação Competitiva , Humanos , Imunoensaio/instrumentação , Cinética , Nefelometria e Turbidimetria , Polímeros/síntese química , Polímeros/metabolismo , Sensibilidade e Especificidade , Albumina Sérica/isolamento & purificação , Albumina Sérica/metabolismo , Solubilidade , Espectrofotometria Ultravioleta , Titulometria
17.
Eur J Cancer Prev ; 2(3): 221-7, 1993 May.
Artigo em Inglês | MEDLINE | ID: mdl-8490540

RESUMO

In order to evaluate the effectiveness of colorectal cancer screening by the faecal occult blood test (FOBT) in Germany a population-based case-control study was conducted in Saarland, a southwestern state of Germany. As cases, we identified 522 persons (244 males, 278 females) who died of colorectal cancer between 1983 and 1986 between the ages of 55 and 75 years. For 163 male cases complete screening histories were retrieved together with up to five age-matched controls who had not died of colorectal cancer identified from the files of the case's referring general practitioner (GP). For 209 female cases screening histories were retrieved from their GPs and gynaecologists as well as for age-matched controls. Individual screening histories were established with emphasis on identifying whether FOBTs were carried out asymptomatically or symptomatically. In the time period 6-36 months prior to diagnosis 13% of the male cases and 14% of the male controls had at least one asymptomatic FOBT with a corresponding matched odds ratio of 0.92 (95% CI: 0.61, 1.75). For the same prediagnostic period 16% of the female cases and 29% of the female controls had at least one asymptomatic FOBT leading to an odds ratio of 0.43 (95% CI: 0.27, 0.68). Thus, for males where participation rates are generally low, no protective effect could be seen but for females where participation rates are higher a clear protective effect is seen. Possibilities for bias need to be taken into consideration when interpreting these results. Organizational measures ensuring a high penetrance of a mass screening programme are seen as a way to elevate efficacy.


Assuntos
Neoplasias do Colo/prevenção & controle , Sangue Oculto , Neoplasias Retais/prevenção & controle , Idoso , Estudos de Casos e Controles , Causas de Morte , Neoplasias do Colo/mortalidade , Medicina de Família e Comunidade , Feminino , Alemanha/epidemiologia , Ginecologia , Humanos , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Razão de Chances , Vigilância da População , Neoplasias Retais/mortalidade , Sistema de Registros , Fatores de Risco
18.
Acta Diabetol ; 40(3): 123-9, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-14605968

RESUMO

Large amounts and excellent viabilities of pancreatic islets are prerequisites for recent advances in islet transplantation. Cryopreservation has been shown to enlarge transplanted cell mass, but has been accompanied by reduced viability. In this study rat pancreatic islets were differentiated into small (<200 micro m), medium (200-400 micrometers) and large (>400 micrometers) categories and their susceptibilities to different freezing conditions were evaluated: concentration of cryoprotectant (0.7-3.1 M), equilibration (15 vs. 45 min, 22 degrees C vs. on ice) and post-thaw removal of cryoprotectant (15 vs. 30 min, stepwise vs. one-step). The most prominent finding was a negative correlation between islet size and viability observed in non-frozen islets to a minor degree (r=-0.44) and significantly enhanced after cryopreservation (r<-0.8). The concentration of cryoprotectant showed the most significant influence on viability affecting small, medium and large islets. Different techniques of equilibration with the cryoprotectant resulted in significant changes of islet viability of medium islets, whereas small and large islets were unaffected. For different techniques of removal of the cryoprotectant, no significant influence on viabilities was found. We conclude that large islets represented a highly susceptible population concerning damage due to cryopreservation.


Assuntos
Criopreservação/métodos , Ilhotas Pancreáticas/citologia , Preservação de Tecido , Trifosfato de Adenosina/metabolismo , Animais , Tamanho Celular , Sobrevivência Celular , Ilhotas Pancreáticas/metabolismo , Masculino , Pâncreas/citologia , Pâncreas/fisiologia , Pancreatectomia , Perfusão , Ratos , Ratos Sprague-Dawley
19.
Ostomy Wound Manage ; 43(8): 14-8, 20, 22, passim, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9385175

RESUMO

This prospective study followed 91 patients in an acute rehabilitation facility from admission until discharge. Of these patients, 35 patients were initially assessed at-risk for pressure ulcers. Demographics, risk status, and pressure ulcer prevention strategies were examined and assessed for at-risk and not at-risk patients. At-risk patients had significantly more medical diagnoses and longer hospitalizations than not at-risk patients, but did not differ by sex, race or age. The following pressure ulcer prevention strategies were considered for both at-risk and not at-risk patients within the first three days of admission: pressure-reducing bed surface, pillows for positioning, lift sheet, heel protection, posted turning schedule, pressure ulcer prevention care plan, pressure ulcer prevention charted, and pressure ulcer prevention educational materials at the bedside. Only the use of pillows for positioning was significant between the two groups; all other preventive strategies were comparable between both groups. For at-risk patients, it is necessary to implement pressure ulcer prevention strategies as early as possible after admission since pressure ulcers may quickly develop.


Assuntos
Admissão do Paciente , Úlcera por Pressão/prevenção & controle , Úlcera por Pressão/reabilitação , Centros de Reabilitação , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação em Enfermagem , Estudos Prospectivos , Fatores de Risco , Fatores de Tempo
20.
Clin Nurse Spec ; 12(1): 7-12; quiz 13-4, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9481258

RESUMO

The purposes of this study about patients with pressure ulcers were to: (a) examine demographic characteristics, laboratory values, Braden Scale scores, and presence of pressure ulcer prevention methods and (b) examine pressure ulcers in terms of classification, stage, wound care, and documentation. The investigation was a prospective, descriptive study; the methods used were patient observations and data recordings from the medical record. Of the patients followed (n = 694), 71 had pressure ulcers. Patients with pressure ulcers were significantly older, with longer lengths of stay, more comorbid conditions, lower blood hemoglobin, lower serum albumin, higher white blood cell counts, and lower Braden Scale scores than patients without pressure ulcers. The presence of pressure ulcer prevention methods was greatly lacking. Nosocomial pressure ulcers tended to be a lower stage compared with pressure ulcers present on admission. Dressings used for wound care were generally gauze or a hydrocolloid. Nurses' charting about pressure ulcers was complete for only 35% of notations. The results of this study indicate that advanced practice nurses have a critical role in caring for patients with pressure ulcers and educating care providers.


Assuntos
Avaliação em Enfermagem/métodos , Planejamento de Assistência ao Paciente/normas , Úlcera por Pressão/etiologia , Úlcera por Pressão/prevenção & controle , Idoso , Bandagens , Feminino , Humanos , Masculino , Auditoria de Enfermagem , Registros de Enfermagem , Úlcera por Pressão/classificação , Estudos Prospectivos , Fatores de Risco
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