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BACKGROUND: Pulmonary artery hypertension (PAH) is a complex disorder that can lead to right heart failure. The generation of caveolin-1 deficient mice (CAV-1-/-) has provided an alternative genetic model to study the mechanisms of pulmonary hypertension. However, the vascular adaptations in these mice have not been characterized. OBJECTIVE: To determine the histological and functional changes in the pulmonary and carotid arteries in CAV-1-/- induced PAH. METHODS: Pulmonary and carotid arteries of young (4-6 months old) and mature (9-12 months old) CAV-1-/- mice were tested and compared to normal wild type mice. RESULTS: Artery stiffness increases in CAV-1-/- mice, especially the circumferential stiffness of the pulmonary arteries. Increases in stiffness were quantified by a decrease in circumferential stretch and transition strain, increases in elastic moduli, and an increase in total strain energy at physiologic strains. Changes in mechanical properties for the pulmonary artery correlated with increased collagen content while carotid artery mechanical properties correlated with decreased elastin content. CONCLUSIONS: We demonstrated that an increase in artery stiffness is associated with CAV-1 deficiency-induced pulmonary hypertension. These results improve our understanding of artery remodeling in PAH.
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Tension-compression testing is commonly conducted to understand and predict springback during a stamping process. However, large strains are generally difficult to achieve during the in-plane compression portion of the test. Proper specimen design and control of frictional forces are necessary for obtaining large strains. This paper describes extensive finite element analyses (FEA) and optimization studies (Phase 1) that were conducted to calibrate the model test assembly for three different buckling modes obtained in uniaxial compression tests of aluminum alloy 2024 and American Iron and Steel Institute (AISI) 1008 steel specimens. In addition to obtaining these three buckling modes correctly, calibrated FEA model predicted forces matched measured forces reasonably well. Also, a good agreement between computed and measured stress-strain data was demonstrated for one compression experiment. In the Phase 2 optimization study, optimum specimen geometries will be developed by using these verified, optimum FEA model test assemblies in three types of compression buckling experiments.
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STUDY DESIGN: The items and response scales of the Spinal Cord Independence Measure (SCIM-III) self report (SR) were exposed to formal cognitive testing with children with SCI, and in parallel a survey using the modified Delphi Technique was conducted to engage content experts in an iterative critical review of the SCIM-III SR. OBJECTIVES: To evaluate the validity of the SCIM-III SR for pediatric utilization. SETTING: United States of America. METHODS: Formal cognitive testing was conducted with 17 youths with SCI and required them to read and answer each SCIM-III SR item aloud. Think aloud methodology was used to record details about how youths understood and interpreted items and why they selected a given response. The interviews were audiotaped and transcribed verbatim. Content analysis focused on identifying words that children could not read or understand. In parallel, the Modified Delphi Technique engaged expert therapists to critically review the SCIM-III SR for pediatric utilization. RESULTS: Every SCIM-III SR item and response scale required modification before children were able to read, understand and respond to them. Youth encountered difficulties because of vague terms, medical jargon and complex words and phrases. Three iterative Delphi rounds were required before achieving 80% agreement that items and response scales were written well for children. CONCLUSION: Our findings informed modifications to every SCIM-III SR item and response scale, producing a pediatric version of the tool that we formally refer to as the SCIM-III SR-Youth (SCIM-III SR-Y). SPONSORSHIP: The study was funded by the Craig H Neilsen Foundation, Spinal Cord Injury Research on the Translation Spectrum, Senior Research Award #282592 (Mulcahey, PI).
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Evaluación de la Discapacidad , Pediatría/métodos , Autoinforme , Traumatismos de la Médula Espinal , Actividades Cotidianas , Adolescente , Niño , Técnica Delphi , Femenino , Humanos , Masculino , AutocuidadoRESUMEN
STUDY DESIGN: Multi-center, prospective calibration study. OBJECTIVES: To examine the psychometric properties of item banks designed for a computer adaptive test of participation. SETTING: Three pediatric specialty care hospitals in North America. METHODS: Newly developed item banks containing questions about participation were administered to 381 children, 8-21 years. Unidimensionality was evaluated using categorical confirmatory factor analysis and residual correlations. Pearson's correlations were calculated between simulated CATs and the full-item banks. RESULTS: CFI=0.905, TLI=0.951 and RMSEA=0.089 for the self-participation item bank; CFI=0.924, TLI=0.963 and RMSEA=0.083 friend-participation item bank. The 15- and 5- item simulated CATs and full-item banks were highly correlated. CONCLUSION: The newly developed self and friend-participation item banks met the required assumptions for CAT. Simulated CATs yielded scores comparable to full-item banks. The results of the study support the use of the item banks for a CAT of participation in children following spinal cord injury.
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Conducta Social , Traumatismos de la Médula Espinal/psicología , Traumatismos de la Médula Espinal/rehabilitación , Actividades Cotidianas , Adolescente , Calibración , Niño , Computadores , Personas con Discapacidad , Femenino , Amigos , Humanos , Vida Independiente , Masculino , Modelos Psicológicos , Autonomía Personal , Estudios Prospectivos , Psicometría , Medio Social , Resultado del Tratamiento , Adulto JovenRESUMEN
Acute disruption of the cutaneous permeability barrier with either solvents or tape-stripping stimulates a homeostatic metabolic response in the subjacent nucleated layers of the epidermis that results in a rapid restoration of normal permeability barrier function. When the aged epidermal permeability barrier is stressed, it reveals a diminished capacity for recovery, in comparison to young epidermis, analogous to other organs in the aged when stressed. Although the signals that regulate this homeostatic response by the epidermis have not yet been resolved, acute permeability barrier disruption stimulates release of prestored IL-1alpha, and increased production of potentially regulatory cytokines, including IL-1alpha and TNFalpha in the epidermis. In these studies, we addressed the hypothesis that cytokine dysregulation explains the permeability barrier abnormality in aged epidermis, assessing the regulation of IL-1 and TNF signaling in aged vs young mice. To determine whether the IL-1 family of cytokines plays a key role in the permeability barrier abnormality of the aged, permeability barrier recovery rates were compared in transgenic mice lacking the functional IL-1 type 1 receptor vs wild-type mice at various ages. Knockout of the IL-1 type 1 receptor exacerbates the defect in permeability barrier homeostasis that is seen in age-matched, wild-type counterparts. Furthermore, the sluggish permeability barrier recovery in aged epidermis is associated with, and at least in part attributable to, altered expression of the IL-1 family of cytokines and receptors both under basal conditions and after acute barrier perturbations. Whereas modulations in cytokine expression with epidermal permeability barrier perturbation are qualitatively similar in aged epidermis, they greatly differ quantitatively. In contrast, examination of TNFalpha mRNA and protein basally, and following barrier perturbation revealed no alterations in aged epidermis. Together, these results show that selective alterations in the IL-1 family of cytokines occur with aging and that defects in IL-1 signaling may contribute to the epidermal permeability barrier abnormality of aged skin.
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Permeabilidad de la Membrana Celular/fisiología , Regulación del Desarrollo de la Expresión Génica , Interleucina-1/genética , Envejecimiento de la Piel/fisiología , Animales , Homeostasis , Inflamación/fisiopatología , Interleucina-1/deficiencia , Interleucina-1/fisiología , Ratones , Ratones Pelados , Ratones Noqueados , Envejecimiento de la Piel/inmunologíaRESUMEN
In two studies, lesbians, gay men and bisexuals were queried concerning mistakes that well-meaning heterosexual people have made when interacting with them. In qualitative, open-ended research, we determined that the most common mistakes concerned heterosexuals' pointing out that they know someone who is gay, emphasizing their lack of prejudice, and relying on stereotypes about gays. Following up with a quantitative, close-ended questionnaire, we determined that the mistakes respondents experienced most often involved heterosexuals (a) relying on stereotypes and (b) ignoring gay issues; the most annoying mistakes were heterosexuals (a) using subtle prejudicial language and (b) not owning up to their discomfort with gay issues. We used two theoretical perspectives, shared reality theory and the contact hypothesis, to analyze the quantitative responses. Implications for intergroup relationships between heterosexual people and gay people are discussed.
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Homosexualidad , Prejuicio , Adulto , Femenino , Heterosexualidad , Humanos , Relaciones Interpersonales , Masculino , Encuestas y CuestionariosRESUMEN
The aim of this prospective study was to histomorphometrically evaluate at various time intervals the mineralization stage and process of an allogeneic-xenogeneic bone graft used in sinus augmentation procedures. One biopsy was taken from 20 patients at either 6, 8, 10, or 12 months after sinus augmentation. Immediately following the biopsy, an endosseous implant was placed into the biopsy site. This protocol provided 4 groups of 5 patients each, based on healing time following sinus augmentation. Using backscattered electron image analysis, the specimens were histomorphometrically analyzed to determine the volume fractions of residual cancellous bone, newly formed bone, soft tissue, bovine hydroxyapatite, and "remineralized" freeze-dried demineralized bone allograft (rDFDBA). "Remineralization" of DFDBA particles was observed in a few areas in all specimens. Polarized light microscopy showed that only the 12-month biopsies had a predominance of lamellar bone formation. The area within the biopsies that represented the residual alveolar ridge consisted of 32.6% +/- 8.6% (mean +/- SD) of bone. In the grafted area of the biopsies the volume fraction of newly formed bone at 12 months (20.7% +/- 8.3%) was significantly higher (P < .05, analysis of variance) than at 6 months (8.1% +/- 3.0%). There was no statistically significant difference between newly formed bone in the inferior, central, and superior grafted areas in all 4 time intervals. This prospective study indicates that the mineralization process of an allogeneic-xenogeneic sinus graft is incomplete 6 months after the sinus augmentation procedure. New bone formation increased up to 12 months postaugmentation; however, it remained lower than the volume of residual bone.
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Trasplante Óseo/métodos , Implantación Dental Endoósea/métodos , Seno Maxilar/cirugía , Procedimientos Quirúrgicos Preprotésicos Orales , Análisis de Varianza , Animales , Regeneración Ósea/fisiología , Bovinos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Estadísticas no Paramétricas , Resultado del TratamientoRESUMEN
The purpose of this study was to compare spontaneous bone regeneration, osteoconduction, and bone autografting in critical size calvarial and mandibular defects (defects which do not heal spontaneously during the lifetime of the animal) that were protected from soft-tissue interposition. Eighteen adult mongrel dogs underwent osteotomies to create a unilateral 30-mm segmental defect in the midbody of the edentulated right mandible and bilateral 15-mm x 20-mm full-thickness window defects in the parietal bones. The defects were either left empty, implanted with coralline hydroxyapatite (HA) blocks, or autografted with iliac cancellous bone. All defects were protected with a macroporous titanium mesh and the segmental mandibular defects were additionally stabilized by internal plate fixation. Specimens were retrieved after 2 and 4 months and three undecalcified longitudinal central sections including the osteotomy interfaces were prepared from each specimen for histometry and histology. Sections were analyzed for volume fractions of bone, soft tissue, and implant using scanning electron microscopy, backscatter electron imaging and histometric computer software. In the mandibular model, the empty defects exhibited the greatest amount of bone formation after 4 months (47.3 percent), which was greater than the amount of bone in the autografted group (34.8 percent) and significantly greater than the amount of bone within the hydroxyapatite implants (19.0 percent, p < 0.05). In the cranial defects, the autografted specimens demonstrated the greatest volume fraction of bone after 4 months (27.3 percent), which was significantly greater than within both the empty defects (18.2 percent, p < 0.05) and the hydroxyapatite implants (18.2 percent, p < 0.05). New bone formation in the mandibular defects united the cut ends at 4 months regardless of treatment and originated predominantly from the periosteum which remained present only along the alveolar border after surgical closure. In the calvarial defects, periosteum was not preserved and bone regenerated centripetally, originating from the diploë without any evidence of dural osteogenesis. Bone bridging was incomplete in the empty cranial defects at 4 months. In both the mandibular and cranial specimens, new bone at 2 months was a mixture of woven and parallel fibered bone. At 4 months, the new bone had remodeled almost entirely into mature Haversian bone. This study demonstrated a remarkable ability of defect protection with a macroporous protective sheet to facilitate bone regeneration in critical size mandibular and cranial bone defects. When active osteogenic periosteum was present, as in our mandibular model, we concluded that defect protection alone was sufficient to allow for healing even of critical size defects. When periosteum was absent as in our cranial defects, the limited spontaneous bone formation benefited from the added contributions of cancellous grafting and osteoconductive implants, both of which promoted bone bridging across the defects. We suggest that in the future a resorbable macroporous protective sheet would be advantageous in comparison to a titanium mesh to facilitate bone regeneration by preventing soft-tissue prolapse and allowing the migration of mesenchymal cells and the proliferation of blood vessels from the adjacent soft tissues into the bone defect. Finally, this study identified the need to differentiate critical size defects into those with and without defect protection and periosteum.
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Regeneración Ósea , Trasplante Óseo/métodos , Enfermedades Mandibulares/cirugía , Osteogénesis , Hueso Parietal/cirugía , Animales , Materiales Biocompatibles , Enfermedades Óseas/patología , Enfermedades Óseas/cirugía , Placas Óseas , Remodelación Ósea/fisiología , Trasplante Óseo/patología , Tejido Conectivo/patología , Perros , Durapatita , Microanálisis por Sonda Electrónica , Estudios de Seguimiento , Osteón/patología , Procesamiento de Imagen Asistido por Computador , Enfermedades Mandibulares/patología , Mesodermo/patología , Mesodermo/fisiología , Microscopía Electrónica de Rastreo , Osteotomía , Hueso Parietal/patología , Periostio/patología , Periostio/fisiología , Porosidad , Prótesis e Implantes , Programas Informáticos , Mallas Quirúrgicas , Titanio , Trasplante Autólogo , Cicatrización de HeridasRESUMEN
Data on porcine and bovine bone marrow composition indicate high calcium content, which may be erroneously elevated owing to the marrow recovery process. A method of bone marrow recovery was developed that involved passing marrow extracted from bone through a filter-press mechanism to remove very fine bone particles and dust, allowing a more accurate analysis of marrow. Calcium values were reduced approximately 90% and ash values reduced more than 50% compared to other reported data. The new recovery method did not require sawing away the hard bone and it removed particulate that may have interfered with analyses. Bone marrow was characterized by bone type. Rib bone marrow had higher protein, iron, non-heme iron and total pigment than scapula, aitch/hip bone or vertebrae marrow. Fat ranged from 17·81 to 26·76% and calcium ranged from 27·25 to 44·33mg 100g(-1) among bone types. The pH of bone marrow ranged from 7·14 to 7·53. Bone marrow appears to contribute to some of the properties of meat obtained from advanced meat recovery systems.
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RATIONALE AND OBJECTIVES: The authors evaluate whether dual-energy x-ray absorptiometry (DXA) is a reliable method to determine the density of natural coralline hydroxyapatite (HA) blocks used as bone graft substitutes. METHODS: To evaluate the basic density of HA blocks from the same coral heads with and without titanium meshes, densitometry of 12 HA-500 blocks (genus Goniopora) and 12 HA-200 blocks (genus Porites) was performed. In addition, density measurements of 30 HA blocks (HA-500, n = 15; HA-200, n = 15) from different coral heads were obtained to assess if the originating coral head influences the basic density of blocks within one coral genera. To assess standard deviation serial measurements on eight coralline HA blocks, four with titanium meshes and four without were performed. In the ex vivo study, densitometry of 12 HA blocks (HA-500, n = 4; HA-200, n = 8) used as bone graft substitutes in the mandibles and craniums of adult mongrel dogs was performed. Densities were measured after bone ingrowth for 2 and 4 months, respectively. All measurements were obtained with a Lunar DPX with scan mode "slow 750" in the spine program with the regions-of-interests selected manually. Bone ingrowth was assessed by computer-assisted histomorphometry, which was considered the gold standard. Statistical analysis was performed to correlate the densities of plain HA blocks with and without meshes to the specific weights of the blocks. RESULTS: Significant positive correlation was found between the density of each HA block (both coral species) with and without meshes and the calculated specific weights. Densitometry values showed no significant differences depending on the originating coral heads. Standard deviation ranged between +/- 3.8% and +/- 4.1% (HA-500) and between +/- 3.0% and +/- 3.8% (HA-200). Hydroxyapatite-500 blocks showed marked increased densities between 15% and 34% after 4 months in three specimens in which bone ingrowth between 16.9% and 21.1% was revealed by histomorphometry; no increase of density was observed in one specimen, which presented only minimal bone ingrowth and signs of infection. Despite bone invasion between 12% and 25.8%, no increased densities were observed for HA-200 implants. CONCLUSIONS: Dual-energy x-ray absorptiometry is an accurate and reproducible modality to assess the densities of plain coralline HA blocks and to monitor bone ingrowth into coralline HA-500 but not into HA-200 block implants.
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Absorciometría de Fotón , Densidad Ósea , Durapatita , Prótesis e Implantes , Animales , Perros , TitanioRESUMEN
PURPOSE: This study determined the incidence of maxillofacial involvement in patients diagnosed with arthrogryposis multiplex congenita (AMC). PATIENTS AND METHODS: Twenty-three patients were evaluated by the pediatric physical medicine and rehabilitation, orthopedic surgery, and pediatric oral and maxillofacial surgery departments. Any patient in whom the diagnosis of AMC was in doubt was excluded from the study. All patients with limited mandibular function underwent computed tomography (CT) examination of their temporomandibular joints (TMJ). The results of physical therapy were followed. RESULTS: Five of the 23 patients diagnosed with AMC were found to have maxillofacial involvement, eg, presence of cleft palate, Robin-like sequence, high-arched palate, open-bite deformity, facial muscle weakness, esophageal dysfunction, and limited mandibular opening. No TMJ abnormalities were found by CT scan. Physical therapy was used for treatment of the limited opening, but relapse occurred quicky after therapy was discontinued. CONCLUSION: The incidence of maxillofacial findings is similar to that of most other reports. Treatment involves surgical correction of abnormal anatomy when possible (ie, cleft repair), symptomatic management (ie, esophageal dysfunction), and physical therapy.
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Artrogriposis/patología , Músculos Faciales/patología , Enfermedades Maxilomandibulares/congénito , Adolescente , Artrogriposis/diagnóstico por imagen , Artrogriposis/cirugía , Artrogriposis/terapia , Niño , Preescolar , Fisura del Paladar/patología , Fisura del Paladar/cirugía , Enfermedades del Esófago/congénito , Femenino , Humanos , Incidencia , Lactante , Masculino , Maloclusión/patología , Enfermedades Mandibulares/congénito , Enfermedades Mandibulares/diagnóstico por imagen , Enfermedades Mandibulares/terapia , Enfermedades Maxilares/patología , Debilidad Muscular/congénito , Hueso Paladar/patología , Modalidades de Fisioterapia , Síndrome de Pierre Robin/patología , Trastornos de la Articulación Temporomandibular/congénito , Trastornos de la Articulación Temporomandibular/diagnóstico por imagen , Trastornos de la Articulación Temporomandibular/terapia , Tomografía Computarizada por Rayos XAsunto(s)
Acetona/farmacología , Epidermis/efectos de los fármacos , Epidermis/patología , Pérdida Insensible de Agua , Animales , Citocinas/metabolismo , Dermatitis/etiología , Epidermis/fisiopatología , Técnicas Histológicas , Homeostasis , Hiperplasia , Masculino , Ratones , Ratones Pelados , Microscopía Electrónica , Factores de Tiempo , Cicatrización de HeridasRESUMEN
Previous studies have shown that barrier disruption increases epidermal mRNA levels of interleukin-1 alpha (IL-1 alpha). We used immunohistochemistry to examine IL-1 alpha expression in hairless mouse skin under basal conditions and following barrier abrogation. In untreated mice, IL-1 alpha was present in the dermis and nucleated epidermal layers in a diffuse, generalized pattern. In essential fatty acid deficient mice IL-1 alpha was present in all epidermal layers and the dermis, with prominent staining in the stratum corneum. After acute barrier disruption with tape-stripping, IL-1 alpha increased in the epidermis and dermis within 10 min, remained elevated at 2 and 4 h, and decreased to near basal levels by 24 h. Moreover, intense, perinuclear, basal cell staining appeared at 10 min, persisting until 4 h after barrier disruption. Since the increase in IL-1 alpha immunostaining after acute barrier abrogation precedes the increase in mRNA, we hypothesized that the IL-1 alpha might derive from a pre-formed pool. Prolonged occlusion of normal skin, a treatment that specifically reduces epidermal mRNA levels of IL-1 alpha, decreased basal immunostaining for IL-1 alpha and blunted the increase in IL-1 alpha usually seen following barrier disruption. Moreover, tape-stripping of skin, maintained ex vivo at 4 degrees C, resulted in increased IL-1 alpha immunostaining within the upper nucleated epidermal layers, as well as release of mature IL-1 alpha into the medium, as measured by Western blotting and enzyme-linked immunosorbent assay. In addition, the stratum corneum attached to the tape contained IL-1 alpha. These studies show that acute barrier disruption induces both the immediate release and dispersion of IL-1 alpha from a pre-formed, epidermal pool, as well as increased IL-1 alpha synthesis; both mechanisms are consistent with a role for IL-1 alpha in the regulation of proinflammatory and homeostatic processes in the skin.
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Interleucina-1/genética , Interleucina-1/metabolismo , Piel/metabolismo , Animales , Epidermis/lesiones , Epidermis/metabolismo , Ácidos Grasos no Esterificados/metabolismo , Expresión Génica , Inmunohistoquímica , Masculino , Ratones , Ratones Pelados , Apósitos Oclusivos , Permeabilidad , ARN Mensajero/genética , ARN Mensajero/metabolismo , Piel/lesionesRESUMEN
This study retrospectively evaluated the results of 36 sinus-lift graft augmentations performed to place 66 implant cylinders in the posterior maxilla where vertical bone height was less than ideal. Grafts were accomplished with porous hydroxyapatite (HA) alone, porous HA mixed with autogenous bone removed from the iliac crest, and HA combined with autogenous bone removed from within the mouth. Nineteen core biopsy specimens were taken from different grafts at time intervals ranging from 4 to 36 months from the time of grafting. These cores were evaluated using histomorphometric analysis to yield data comparing volume fractions of bone formation, allowing comparison of different graft materials and healing times. Grafts using porous HA alone on mean produced 16.38% bone by volume after 6 months. After the same healing time, grafts using HA and hip bone on mean produced 19.30% bone by volume compared with an 11.30% bone volume when using HA and bone harvested intraorally. Evaluation of cores taken at 19 and 36 months revealed greater volumes of bone formation. Recommendations based on clinical and histologic results are discussed in detail.
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Aumento de la Cresta Alveolar/métodos , Implantación Dental Endoósea , Implantes Dentales , Maxilar/cirugía , Seno Maxilar/cirugía , Adolescente , Adulto , Anciano , Biopsia , Trasplante Óseo/métodos , Trasplante Óseo/patología , Diseño de Prótesis Dental , Prótesis Dental de Soporte Implantado , Durapatita , Femenino , Estudios de Seguimiento , Humanos , Ilion , Maxilares , Masculino , Maxilar/patología , Seno Maxilar/patología , Persona de Mediana Edad , Osteogénesis , Prótesis e Implantes , Falla de Prótesis , Estudios Retrospectivos , Titanio , Resultado del Tratamiento , Cicatrización de HeridasRESUMEN
This paper presents estimates of the impact of the age pattern and level of fertility on the probability of labor force participation by married and cohabiting women in 12 eastern and western European countries and the US. Logit models for labor force participation probabilities are estimated conditional on age, age at marriage or union, educational attainment, current parity, and number of years in parity, using data on married and cohabiting women from the UN Economic Commission for Europe (UNECE) Comparative Study of World Fertility Surveys. The estimated models are used to simulate the age profiles of labor force participation conditional on the level and timing of fertility. The simulation results are presented in a series of charts grouped according to similarities in the effects of fertility on the age profiles of labor force participation. Four distinct patterns are identified that depend on the empirical significance of distinct number-of-children and age-of-youngest-child effects. The role of family policies and the extent to which the labor supply reductions associated with childbearing can be interpreted as opportunity costs are considered.
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Factores de Edad , Tasa de Natalidad , Economía , Empleo , Modelos Teóricos , Paridad , Estadística como Asunto , Américas , Demografía , Países Desarrollados , Europa (Continente) , Fertilidad , Fuerza Laboral en Salud , América del Norte , Población , Características de la Población , Dinámica Poblacional , Investigación , Clase Social , Factores Socioeconómicos , Estados UnidosRESUMEN
The goal among critical care staff of discontinuing mechanical support in a prudent and expeditious manner emerges immediately after intubation. This goal, known as the weaning process, contains the three phases of optimizing the patient's condition, assessing and evaluating the patient's progress, and diagnostic testing. As a diagnostic test, the wean trial needs to be standardized for efficiency and safety. To maximize safe and efficient delivery of the trial, the primary nurse and respiratory therapist should be the responsible professional monitors. The standardized trial enhances staff confidence for safe extubation. A successful standardized weaning protocol eases the transition from mechanical ventilation to spontaneous breathing for the patient and improves the professional performance and confidence of critical care staff.
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Protocolos Clínicos/normas , Evaluación en Enfermería/normas , Planificación de Atención al Paciente/normas , Desconexión del Ventilador/normas , Humanos , Mediciones del Volumen Pulmonar , Desconexión del Ventilador/enfermeríaRESUMEN
This paper presents indirect estimates of desired family size and unwanted births for married and cohabiting women in 12 European countries and the US. An econometric model for censored discrete data is used to estimate the distribution of desired family size from individual observations on children ever-born and total expected births. The data are from the UNECE Comparative Fertility Study of WFS surveys for Europe and the US and originated in national surveys between April 1975-December 1979. Estimates of the bivariate distribution of cumulative and desired fertility are used to compute the proportion of women with excess fertility and the average number of unwanted births for each country. The indirect estimates are compared with those from an analysis of survey responses to questions about desired and unwanted births. Multivariate modes that control for the effects of marriage duration, age at marriage, education, employment status, work experience, and total family income are also reported.
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Tasa de Natalidad , Composición Familiar , Fertilidad , Estado Civil , Matrimonio , Modelos Económicos , Embarazo no Deseado , Proyectos de Investigación , Factores Socioeconómicos , Estadística como Asunto , Américas , Demografía , Países Desarrollados , Economía , Europa (Continente) , Modelos Teóricos , América del Norte , Población , Dinámica Poblacional , Investigación , Conducta Sexual , Estados UnidosRESUMEN
We report here that nucleolar and cytoplasmic RNA in mammalian cells is recognized specifically by both experimentally induced monoclonal IgG unique for left-handed Z-RNA and by autoimmune mouse monoclonal IgG specific for ribosomal RNA. Nucleolar Z-RNA synthesis, like nucleolar ribosomal RNA synthesis, is inhibited by actinomycin D treatment and dimethylsulfoxide-induced differentiation. Immune anti-Z-RNA IgGs microinjected into living nuclei bind nucleolar RNA, and these complexes appear to be removed from the nucleus within minutes. Cytoplasmically microinjected monoclonal or polyclonal anti-Z-RNA IgGs specifically bind cytoplasmic RNA and inhibit cell multiplication. Microinjection of antibodies directed against double-stranded RNAs. Elevated ionic conditions, which in energy-minimized models can cause the walls of the groove in Z-RNA (but not Z-DNA) to approach each other and close, also prevent antibody binding to specific synthetic or cellular Z-RNA determinants. Our antibodies binding unique Z-RNA structures probably recognize antigens determined by the exposed 2'-OH ribose sugar-phosphate groups.
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Anticuerpos Monoclonales , Inmunoglobulina G , ARN Neoplásico/inmunología , Células Tumorales Cultivadas/citología , Animales , Anticuerpos Monoclonales/administración & dosificación , Anticuerpos Monoclonales/aislamiento & purificación , Complejo Antígeno-Anticuerpo , Carcinoma Hepatocelular , Línea Celular , Nucléolo Celular/ultraestructura , Citoplasma/ultraestructura , Femenino , Técnica del Anticuerpo Fluorescente , Humanos , Inmunoglobulina G/administración & dosificación , Inmunoglobulina G/aislamiento & purificación , Neoplasias Hepáticas , Ratones , Ratones Endogámicos BALB C/inmunología , Microinyecciones , Modelos Estructurales , Conformación de Ácido Nucleico , ARN Neoplásico/metabolismo , Células Tumorales Cultivadas/ultraestructuraRESUMEN
A Connecticut insurance company adopted a policy prohibiting smoking in all work areas. Three months later, the authors assessed smoking behavior changes and attitudes of a sample of 1,210 employees, 56.6 percent of the total. The survey showed that the policy of no smoking in the work areas did not markedly affect smoking cessation, that it reduced cigarette consumption for those who continued to smoke, that those who previously smoked most were most likely to reduce consumption, and that despite negative feelings about the policy by smokers, only 29 percent of smokers and 4 percent of nonsmokers wanted a worksite smoking policy eliminated. During the 1-year prepolicy period, smoking prevalence decreased from 25.2 percent to 23.6 percent of the sample. During the 3-month postpolicy period, smoking prevalence decreased to 22.0 percent. During the prepolicy period, consumption did not change significantly (from 0.99 to 0.95 packs per day) and few smokers increased (11 percent) or decreased (13 percent) consumption. During the postpolicy period, consumption decreased by 32 percent to 0.67 packs per day, and 12 times as many smokers decreased (44 percent) as increased (3.5 percent) consumption. Of those who smoked at least two packs per day, 93 percent smoked less after the policy. Among nonsmokers, 70 percent thought the policy had a positive overall effect on the work environment, compared with 19 percent of smokers.