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1.
Sci Rep ; 14(1): 158, 2024 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-38168495

RESUMEN

Movement of resources was essential to the survival and success of early complex societies. The sources and destinations of goods and the means of transportation - be it by boats, carts and/or foot - can often be inferred, but the logistics of these movements are inherently more difficult to ascertain. Here, we use strontium isotopic analysis to test hypotheses about the role of animal and animal-powered transport in medium and long-distance movement and exchange, using the Indus Civilization as a case study. Across the wide geographical spread of the Indus Civilisation, there is strong evidence for long-distance exchange of raw materials and finished objects and this process is presumed to involve boats and animal-driven transport, although there is little evidence as to the relative importance of each mode of movement. Strontium isotopic analysis of animal remains from four sites analysed for this study combined with results from nine other sites indicates limited long-distance animal movement between different geological zones within the Indus Civilisation. These findings suggest that individual animals primarily moved short- or medium-distances, though there are several significant exceptions seen in some pigs and cattle found at two large urban sites. We infer that long-distance transport of goods, be it raw materials, finished objects, other goods, or the animals themselves, could have occurred through the use of boats and waterways, by traction animals moving over long distances that did not end up in the archaeological record, and/or by different animals participating in many short to medium-distance movements.


Asunto(s)
Pezuñas y Garras , Animales , Bovinos , Porcinos , Isótopos de Estroncio , Arqueología , Transportes , Civilización , Movimiento
2.
Int J Oral Maxillofac Surg ; 50(12): 1596-1602, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34074576

RESUMEN

Recurrent fractures of the mandible are rare, however in Darwin, Australia, their occurrence is relatively frequent. This retrospective study identified 127 patients with 148 recurrent mandibular fractures treated at Royal Darwin Hospital between 2000 and 2017. Age, sex, ethnicity, marital status, aetiology, risk factors, anatomical location of the fractures, fracture patterns, and management of the fractures were analysed. The majority of patients were male (85.8%) (P < 0.001); 62.8% were unmarried (P < 0.001) and 72.4% were indigenous (P < 0.001). Alcohol was involved in 79.1% of cases (P < 0.001) and assault was the most common mechanism of injury (84.5%) (P < 0.001). The angle of the mandible was the most common site (P < 0.001), and recurrent fractures were more likely to occur at sites different to a previous fracture fixation site (P < 0.001). Smoking, alcohol abuse, and diabetes were strongly associated with recurrent fractures (all P < 0.001). Most patients were managed with open reduction internal fixation. In conclusion, recurrent fractures of the mandible frequently involved the angle of the mandible and occurred at different sites. Their incidence was more common among the unmarried, male, and indigenous population, and smoking, alcohol abuse, and diabetes were found to be significant risk factors.


Asunto(s)
Fracturas Mandibulares , Femenino , Fijación de Fractura , Fijación Interna de Fracturas , Humanos , Incidencia , Masculino , Mandíbula , Fracturas Mandibulares/epidemiología , Estudios Retrospectivos
3.
Am J Phys Anthropol ; 154(4): 535-43, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24888560

RESUMEN

Patterns of water consumption by past human populations are rarely considered, yet drinking behavior is socially mediated and access to water sources is often socially controlled. Oxygen isotope analysis of archeological human remains is commonly used to identify migrants in the archeological record, but it can also be used to consider water itself, as this technique documents water consumption rather than migration directly. Here, we report an oxygen isotope study of humans and animals from coastal regions of Croatia in the Iron Age, Roman, and Early Medieval periods. The results show that while faunal values have little diachronic variation, the human data vary through time, and there are wide ranges of values within each period. Our interpretation is that this is not solely a result of mobility, but that human behavior can and did lead to human oxygen isotope ratios that are different from that expected from consumption of local precipitation.


Asunto(s)
Dieta/etnología , Dieta/historia , Ingestión de Líquidos/etnología , Animales , Croacia/etnología , Historia Antigua , Historia Medieval , Humanos , Isótopos de Oxígeno/análisis , Diente/química , Abastecimiento de Agua/historia
4.
Am J Phys Anthropol ; 148(4): 543-56, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22552855

RESUMEN

Food is well-known to encode social and cultural values, for example different social groups use different consumption patterns to act as social boundaries. When societies and cultures change, whether through drift, through population replacement or other factors, diet may also alter despite unchanging resource availability within a region. This study investigates the extent to which dietary change coincides with cultural change, to understand the effects of large-scale migrations on the populations' diets. Through stable carbon and nitrogen isotope analysis of Iron Age, Roman, and Early Medieval human bone collagen, we show that in Croatia large-scale cultural change led to significant changes in diet. The isotopic evidence indicates that Iron Age diet consisted of C(3) foodstuffs with no isotopic evidence for the consumption of C(4) or marine resources. With the Roman conquest, marine resources were added to the diet, although C(3) foodstuffs continued to play an important role. In the Early Medieval period, this marine component was lost and varying amounts of C(4) foodstuffs, probably millet, were added to the otherwise C(3) diet. In both of these transitions it is likely that the changes in diet are related to the arrival of a new people into the area.


Asunto(s)
Antropología Física , Evolución Cultural , Dieta/historia , Huesos/química , Isótopos de Carbono/análisis , Colágeno Tipo I/química , Croacia/etnología , Dieta/etnología , Grano Comestible , Historia Antigua , Historia Medieval , Humanos , Isótopos de Nitrógeno/análisis , Alimentos Marinos
5.
Biotechnol Bioeng ; 87(3): 259-73, 2004 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-15281101

RESUMEN

Here we review key applications of separation technology in applied biology. We first sketch out the field as a whole, but then narrow our scope to the processing of fermentation products, particularly to high-value biologicals such as proteins and nucleotides. We go on to provide a qualitative overview describing the importance and general nature of this large field, major trends, and the strategies that have proven most fruitful in evolving effective separation and purification processes. We then give a detailed description of individual separations equipment and the principles governing their operation. We concentrate throughout on making the available literature accessible to the reader; we provide what is hoped to be a representative set of basic references. However, these references, in turn, include some that suggest promising new developments as well as a number of more specialized reviews. We hope that our overall result provides the reader with access to the most relevant literature.


Asunto(s)
Biopolímeros/aislamiento & purificación , Separación Celular/instrumentación , Fraccionamiento Químico/métodos , Cromatografía/instrumentación , Cromatografía/métodos , Ultrafiltración/instrumentación , Ultrafiltración/métodos , Biotecnología/instrumentación , Biotecnología/métodos , Separación Celular/métodos , Fraccionamiento Químico/instrumentación , Cristalización/instrumentación , Cristalización/métodos , Diseño de Equipo , Análisis de Falla de Equipo , Membranas Artificiales , Modelos Químicos
6.
J Chromatogr A ; 989(1): 165-73, 2003 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-12641292

RESUMEN

Adsorptive membranes were investigated for the downstream processing of plasmid DNA by quantifying both separation efficiencies and adsorption uptake with the anion-exchange membranes. Separation efficiencies of the 10-ml Mustang-Q were measured using pulses of 6.1-kilo base pair plasmid DNA and lysozyme tracers, and comparing the responses for both conventional and reverse-flow operation. The plasmid exhibited nearly 200 plates/cm, almost as high efficiency as the protein despite the large difference in size. This behavior contrasts strongly with typical behavior for spherical porous particle packings, which predicted large decreases in efficiency with increases in tracer size. Batch adsorption isotherms for the 6.1-kilo base pair plasmid on small sheets of anion-exchange membranes at various ionic strengths showed high capacities for very large biomolecules. The maximum binding capacity for the membrane unit was calculated as 10 mg plasmid/ml, an order of magnitude greater than typical values reported for porous beads.


Asunto(s)
Cromatografía Liquida/métodos , ADN/aislamiento & purificación , Adsorción , Resinas de Intercambio Aniónico , Electroforesis en Gel de Agar , Membranas Artificiales , Plásmidos
7.
J Neurosci ; 20(12): 4435-45, 2000 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-10844012

RESUMEN

Genetic transfer of growth-promoting molecules was proposed as a potential strategy to modify the nonpermissive nature of the adult CNS to induce axonal regeneration. To evaluate whether overexpression of neurotrophins or cellular adhesion molecules would effect axonal plasticity, adenoviruses encoding fibroblast growth factor-2 (FGF-2/Adts), nerve growth factor (NGF/Adts), neurotrophin-3, and the cell adhesion molecules N-cadherin and L1 were injected into the dorsal horn of the adult spinal cord. Transgene expression was primarily localized to astrocytes in the dorsal horn and motor neurons within the ventral horn. Overexpression of these factors, with the exception of NGF/Adts, failed to increase axonal sprouting. Eight days after NGF/Adts injections, axonal sprouting within the dorsal horn was apparent, and after 4 weeks, extensive spouting was observed throughout the entire dorsal horn, extending into the ventral horn and the white matter of the lateral funiculus. These axons were identified primarily as a subpopulation of nociceptive fibers expressing calcitonin gene-related peptide and substance-P. Behavioral analysis revealed thermal hyperalgesia and perturbation of accurate paw placement on grid-walking tasks for both FGF-2- and NGF-treated animals. These results indicate that the administration of growth-promoting molecules can induce robust axonal plasticity of normal adult primary sensory neurons into areas of transgene expression, causing significant alterations in behavioral responses. This observation also indicates that gene transfer protocols that aim to reconstruct diseased or injured pathways should also be designed to prevent the sprouting of the normal circuitry from adjacent unaffected neurons.


Asunto(s)
Axones/fisiología , Factor 2 de Crecimiento de Fibroblastos/genética , Hiperalgesia/fisiopatología , Factor de Crecimiento Nervioso/genética , Plasticidad Neuronal/fisiología , Neuronas/fisiología , Médula Espinal/fisiología , Células 3T3 , Fosfatasa Ácida/análisis , Adenoviridae , Vías Aferentes , Animales , Astrocitos/fisiología , Adhesión Celular , División Celular , Supervivencia Celular , Factor 2 de Crecimiento de Fibroblastos/fisiología , Técnicas de Transferencia de Gen , Hiperalgesia/genética , Ratones , Neuronas Motoras/fisiología , Factor de Crecimiento Nervioso/fisiología , Neuronas/citología , Neuronas Aferentes/fisiología , Neurotensina/análisis , Células del Asta Posterior/fisiología , Ratas , Ratas Sprague-Dawley , Médula Espinal/fisiopatología
8.
Shock ; 11(1): 29-34, 1999 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9921713

RESUMEN

The hypothesis that cardiac functional abnormalities that occur after major burn trauma are paralleled by an increased incidence of apoptosis in cardiac myocytes was examined. Adult Sprague-Dawley rats were given a full thickness scald burn comprising 43+/-1% of the total body surface area or were manipulated identically but not exposed to burn injury (sham burn); burned rats were fluid resuscitated with lactated Ringer's solution. Tissues from burn and sham burn animals were then examined by the TUNEL (TdT-mediated dUTP nick end labeling) assay and light microscopy to determine the presence of apoptosis 24 and 48 h after burn trauma. In parallel, the mechanical function of the heart was assayed in separate groups of rats. Tissues harvested from the hearts of sham-treated animals showed essentially no apoptosis, whereas a small number of apoptotic cells were noted in the intestinal villi and liver of sham-treated animals. Twenty-four hours after burn trauma, there was a marked increase in apoptotic cells in the left ventricle (+916%), and the number of apoptotic cells remained increased by eightfold 48 h postburn. Apoptosis was noted predominately in the subendocardial tissue of the left ventricle. The appearance of apoptotic cells was paralleled by a decrease in cardiac mechanical function with significant decreases in left ventricular pressure and +/-dP/dt(max). Burn injury also increased apoptosis in the small intestine significantly, whereas apoptosis in the liver did not increase with burn trauma. These data suggest that the apoptosis of the cardiac myocytes that occurs after burn trauma may contribute, in part, to postburn cardiac mechanical dysfunction.


Asunto(s)
Apoptosis , Quemaduras/patología , Sistema Digestivo/patología , Miocardio/patología , Choque Traumático/patología , Animales , Quemaduras/fisiopatología , Sistema Digestivo/fisiopatología , Contracción Miocárdica , Ratas , Ratas Sprague-Dawley , Choque Traumático/fisiopatología
9.
J Chromatogr A ; 796(1): 3-14, 1998 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-9513280

RESUMEN

The use of heavily loaded columns and complex processing conditions makes scale-up of chromatographic separations a non-trivial process. The wide ranges of process conditions that must be investigated demands that a large number of preliminary experiments must usually be made in small columns and laboratory-scale work stations. These preliminary data can be biased by improper column packing, poor distributors and dispersion in auxiliary apparatus, and it is important to understand these disturbing factors in detail. Moreover, it is precisely at this macroscopic level that our understanding of the chromatographic process is weakest, for large columns as well as small. This paper addresses three of these factors: Efficient elimination of peripheral effects and characterization of both header flow distribution and packing non-uniformity. This will be done using a variety of experimental and analytical approaches including nuclear magnetic resonance imaging, computational fluid dynamics and mass transfer, and careful experimentation.


Asunto(s)
Cromatografía Liquida/métodos , Acetona/química , Espectroscopía de Resonancia Magnética , Modelos Químicos , Muramidasa/química
10.
Anal Chem ; 69(16): 3293-8, 1997 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-9271069

RESUMEN

A novel method for measuring resin porosities and column void volumes with fluorine. NMR has not been developed. In situ measurements of the void volumes accessible to an array of fluorinated probe molecules are used to characterize the pore size distribution of the media. Application of this simple procedure is demonstrated for a commercially packed column and several bulk resins. The porosity distributions obtained by this technique are similar to those obtained by size exclusion chromatography. Unlike chromatographic tracer studies, however, this method does not require packed columns.


Asunto(s)
Espectroscopía de Resonancia Magnética/métodos , Resinas de Plantas/química
11.
J Surg Res ; 63(1): 355-8, 1996 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8661225

RESUMEN

Inflammation and microvascular injury in the areas adjacent to burn wounds produces extension of postburn tissue necrosis. Leukocytes are potent mediators of the local inflammatory response preceding tissue necrosis, and the selectin and integrin adhesion molecules have been implicated in leukocyte-mediated tissue destruction. We sought to examine the role of L-selectin (CD62-L) and CD18 in leukocyte accumulation and tissue necrosis following burn injury. New Zealand White rabbits (n = 36) were subjected to burn injury and were randomized to treatment with saline (control) or monoclonal antibodies to L-selectin or CD18. Animals given the anti-L-selectin antibody demonstrated reduced immunohistochemical evidence of leukocyte accumulation at 24 hr postinjury but did not show improved wound perfusion or reduced tissue necrosis. Animals in the anti-CD18 group showed significantly improved tissue survival and improved tissue perfusion but had grades of leukocyte accumulation similar to those in the control group. These observations suggest that leukocyte accumulation is partially L-selectin dependent and that leukocyte accumulation alone is not sufficient to cause changes in blood flow and tissue destruction, both of which appear to be largely CD18 mediated.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Quemaduras/fisiopatología , Antígenos CD18/fisiología , Inflamación/prevención & control , Selectina L/fisiología , Leucocitos/fisiología , Piel/irrigación sanguínea , Cicatrización de Heridas , Animales , Antígenos CD18/inmunología , Humanos , Inmunoglobulina G/uso terapéutico , Inmunohistoquímica , Selectina L/inmunología , Conejos , Flujo Sanguíneo Regional , Factores de Tiempo
12.
Burns ; 22(4): 324-7, 1996 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8781731

RESUMEN

Partial and full thickness burns with intervening zones of stasis were created on the backs on New Zealand White rabbits (n = 23). Either saline or the bradykinin receptor antagonist, NPC 17731, was administered. Skin blood flow was measured hourly using a laser Doppler blood flowmeter. After 4 h skin samples were harvested for assessment of tissue oedema (wet/dry weights) and leucocyte accumulation (immunohistochemistry). Statistical analysis was performed using Analysis of variance (ANOVA) and Mann-Whitney U test with a level of significance at P < 0.05. It was found that blood flow was decreased postburn in all groups. Bradykinin antagonist resulted in increased blood flow in partial thickness burns and zones of stasis compared to saline-treated animals (P < 0.05). Pretreatment with bradykinin antagonist showed reduced tissue oedema in full thickness burns (P < 0.05). No significant difference was observed in leucocyte accumulation between both groups. These data suggest a role for bradykinin in the pathogenesis of postburn microvascular changes which is independent of leucocyte-mediated injury.


Asunto(s)
Antagonistas de los Receptores de Bradiquinina , Quemaduras/tratamiento farmacológico , Dermatitis/tratamiento farmacológico , Oligopéptidos/farmacología , Piel/irrigación sanguínea , Análisis de Varianza , Animales , Velocidad del Flujo Sanguíneo/efectos de los fármacos , Bradiquinina/fisiología , Quemaduras/patología , Quemaduras/fisiopatología , Dermatitis/patología , Dermatitis/fisiopatología , Edema/tratamiento farmacológico , Edema/patología , Edema/fisiopatología , Inmunohistoquímica , Infusiones Intravenosas , Flujometría por Láser-Doppler , Oligopéptidos/administración & dosificación , Conejos , Piel/efectos de los fármacos , Piel/patología
13.
J Trauma ; 40(4): 564-7, 1996 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8614033

RESUMEN

OBJECTIVE: To determine if the shock-induced alterations in whole blood monocyte tumor necrosis factor (TNF) response are mediated by the CD14 receptor. DESIGN: Prospective controlled animals experiments. MATERIALS AND METHODS: New Zealand White rabbits (n = 15) were subjected to hemorrhage and resuscitation. Blood samples obtained before shock and 24, 72, and 120 hours after shock were stimulated with lipopolysaccharide in the presence or absence of the anti-CD14 monoclonal antibody, 63D3. Tumor necrosis factor was assayed using L929 cells. MEASUREMENTS AND MAIN RESULTS: There are no detectable TNF activity in unstimulated blood. The CD14 inhibition resulted in a 55% reduction in baseline TNF activity. After shock, there was a marked increase in TNF activity with lipopolysaccharide stimulation. Addition of 63D3 resulted in a dose-dependent 95% reduction in TNF activity at 24 and 72 hours after shock, (p < 0.05). CONCLUSION: The enhanced whole blood monocyte TNF response after hemorrhage is CD14 dependent.


Asunto(s)
Receptores de Lipopolisacáridos/fisiología , Monocitos/metabolismo , Choque Hemorrágico/sangre , Factor de Necrosis Tumoral alfa/biosíntesis , Animales , Estudios Prospectivos , Conejos , Choque Hemorrágico/fisiopatología
14.
J Am Med Inform Assoc ; 3(1): 27-37, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8750388

RESUMEN

The objective of the Willow Project is to develop a uniform search interface that allows a diverse community of users to retrieve information from heterogeneous network-based information resources. Willow separates the user interface from the database management or information retrieval system. It provides a graphic user interface to a variety of information resources residing on diverse hosts, and using different search engines and idiomatic query languages through networked-based client-server and Transmission Control Protocol/Internet Protocol (TCP/IP) protocols. It is based on a "database driver'' model, which allows new database hosts to be added without altering Willow itself. Willow employs a multimedia extension mechanism to launch external viewers to handle data in almost any form. Drivers are currently available for a local BRS/SEARCH system and the Z39.50 protocol. Students, faculty, clinicians, and researchers at the University of Washington are currently offered 30 local and remote databases via Willow. They conduct more than 250,000 sessions a month in libraries, medical centers and clinics, laboratories, and offices, and from home. The Massachusetts Institute of Technology is implementing Willow as its uniform search interface to Z39.50 hosts.


Asunto(s)
Redes de Comunicación de Computadores , Almacenamiento y Recuperación de la Información , Servicios de Biblioteca , Diseño de Software , Interfaz Usuario-Computador , Gráficos por Computador , Seguridad Computacional , Washingtón
15.
Am J Physiol ; 269(6 Pt 1): E1115-24, 1995 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8572205

RESUMEN

Many diabetic patients taking multiple subcutaneous insulin injections cannot adjust their dosage appropriately to maintain blood glucose within a normal range. It is hard to predict how dosage changes and physiological fluctuations affect insulin levels and subsequently glucose control. To examine these issues, we have developed a model representing the link between dosage and blood insulin levels. Our model adequately predicts insulin concentrations for individual patients and could be incorporated into an overall glucose-insulin representation. More importantly, parameter and sensitivity analysis results highlight insulin kinetic features that are difficult to isolate in a clinical setting and that may significantly influence glucose dynamics. For example, large interpatient variation, measured quantitatively by model parameters, emphasizes the need for individualized design of insulin regimens. Intrapatient variations are also large in some patients. Improved control for these patients may only be possible through more frequent sampling and control action. The sensitivity coefficient for absorption suggests a significant overlapping injection effect that is not considered in present patient management strategies.


Asunto(s)
Diabetes Mellitus/sangre , Insulina/administración & dosificación , Modelos Biológicos , Diabetes Mellitus/tratamiento farmacológico , Relación Dosis-Respuesta a Droga , Humanos , Inyecciones Subcutáneas , Insulina/sangre , Insulina/uso terapéutico
16.
J Trauma ; 39(2): 285-8, 1995 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7545762

RESUMEN

OBJECTIVE: To determine if thermal injury alters the expression of leukocyte adhesion molecules. DESIGN: This is a controlled experimental animal study. MATERIALS AND METHODS: Partial thickness burns were created on the backs of New Zealand White rabbits. At 30 minutes, 2 hours, 4 hours, and 24 hours after burn, skin was harvested for immunohistochemistry. Monoclonal antibodies were used to study changes in intercellular adhesion molecule 1 (ICAM-1), E-selectin, and leukocyte CD11a. Staining was graded on a scale of 0 to 4. MEASUREMENTS AND MAIN RESULTS: ICAM-1 was significantly decreased at 24 hours after burn (p < 0.007, Wilcoxon signed rank test). CD11a was increased at 30 minutes (p < 0.02), 2 hours (p < 0.02), and 24 hours (p < 0.006). E-selectin was increased at 2 hours (p < 0.03). CONCLUSION: Thermal injury alters the expression of leukocyte adhesion molecules.


Asunto(s)
Quemaduras/inmunología , Molécula 1 de Adhesión Intercelular/metabolismo , Animales , Anticuerpos Monoclonales , Quemaduras/patología , Moléculas de Adhesión Celular/metabolismo , Selectina E , Prueba de Inhibición de Adhesión Leucocitaria , Antígeno-1 Asociado a Función de Linfocito/metabolismo , Conejos
17.
Bioseparation ; 4(3): 183-200, 1994 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7765180

RESUMEN

Short chromatographic columns prepared from stacks of microporous adsorptive membranes are promising for preparative-scale fractionation of even rather closely related proteins, but careful selection of operating conditions is needed for success. It has been shown that existing devices exhibit very low internal diffusional resistance, and that resolution is almost totally independent of percolation velocity. Total column length is short, however, and the number of plates exhibited under isocratic low-loading conditions is small, on the order of 100. Simulations using a large survey of protein thermodynamic data show that one can frequently obtain excellent protein separations in these short columns by using the sensitivity of protein adsorption equilibria to eluting solvent composition. In fact, some proteins can be separated in a single stage utilizing this 'on-off' behavior and properly selected solvent gradients. Solely on-off, or differential elution, behavior cannot often be depended upon under the mild conditions need for preparative operations. Carefully programmed gradient elution can frequently produce acceptable purification by maximizing both differential elution and differential migration, resulting in protein separations in columns of less than fifty plates. Means for doing this are described for some simple situations, and criteria are provided for selecting modulator gradient schedules.


Asunto(s)
Cromatografía Liquida/métodos , Proteínas/aislamiento & purificación , Animales , Cromatografía Liquida/instrumentación , Modelos Químicos
18.
J Trauma ; 36(5): 714-8; discussion 718-9, 1994 May.
Artículo en Inglés | MEDLINE | ID: mdl-7514672

RESUMEN

Leukocyte (WBC) adherence to endothelial cells has been implicated in the pathogenesis of microvascular injury. The process of leukocyte adherence is mediated by both the integrin and selectin families of molecules, and their interaction with specific endothelial ligands. Antibodies directed against the leukocyte integrin CD18 and L-selectin have been developed and functionally inhibit leukocyte adherence in models of inflammatory injury. We asked the question: Does inhibition of leukocyte adherence by administration of monoclonal antibody directed against either CD18, integrins (R15.7, R7.1) or against L-selectin (DREG 200) increase susceptibility to infection? New Zealand white rabbits were shaved and injected subcutaneously on their dorsum with Pseudomonas aeruginosa (ATCC#27853) at two sites each of 10(8) and 10(7) colony forming units. Animals were monitored with daily determination of weight, temperature, WBC counts, hematocrit, and killed at 1 week for determination of abscess formation. There were four blinded experimental groups: (1) Saline (2 mL/kg); (2) DREG 200 (2 mg/kg); (3) R7.1 (2 mg/kg); or (4) R15.7 (2 mg/kg). At the 10(7) and 10(8) injection sites the R15.7 group had an increased rate and size of abscess formation compared with controls. The R7.1 group had an increased rate at the 10(8) injection site. There was no significant difference in the percentage of the abscess formation or mean area between the controls and DREG 200-treated groups. We conclude that giving antibody to CD18 increased susceptibility to infection while giving antibody to L-selectin does not.


Asunto(s)
Anticuerpos Monoclonales/farmacología , Antígenos CD/inmunología , Moléculas de Adhesión Celular/inmunología , Leucocitos/efectos de los fármacos , Infecciones por Pseudomonas/inmunología , Receptores de Adhesión de Leucocito/antagonistas & inhibidores , Receptores Mensajeros de Linfocitos/antagonistas & inhibidores , Animales , Antígenos CD18 , Adhesión Celular/efectos de los fármacos , Adhesión Celular/inmunología , Susceptibilidad a Enfermedades , Selectina L , Leucocitos/inmunología , Conejos , Receptores de Adhesión de Leucocito/inmunología , Receptores Mensajeros de Linfocitos/inmunología
19.
J Burn Care Rehabil ; 14(6): 610-6, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-7905484

RESUMEN

Leukocytes and the process of leukocyte adherence have been implicated in the pathogenesis of organ dysfunction after ischemic injury and inflammation. We asked the question: Will inhibition of leukocyte adherence by administration of a monoclonal antibody to intercellular adhesion molecule alter the systemic response to major thermal injury? New Zealand white rabbits instrumented to measure mean arterial pressure, cardiac output, urine output, and arterial oxygenation were deeply anesthetized, and 30% total body surface area full-thickness burn was created by applying brass probes heated to 100 degrees C to the animals' backs for 15 seconds. The animals were continuously monitored, resuscitated, and given analgesic for 24 hours. There were three experimental groups: I-controls (n = 7), anesthetized and monitored; II-30% burn (n = 7) given 30% total body surface area + vehicle (saline solution 1.0 ml/kg every 8 hours); III-30% burn + R6.5 (n = 6) animals given a monoclonal antibody (R6.5, 2.0 mg/kg every 8 hours) directed against the intercellular adhesion molecule beginning 30 minutes after burn. This model of a 30% total body surface area burn injury resulted in hypotension and hypoxemia in the burn group. The animals given the antibody R6.5 maintained higher mean arterial pressure and arterial oxygenation at several points. These results suggest that leukocytes and leukocyte adherence may be involved in the pathogenesis of the systemic sequellae of major thermal injury.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Antígenos CD/inmunología , Quemaduras/terapia , Moléculas de Adhesión Celular/inmunología , Leucocitos/fisiología , Animales , Quemaduras/complicaciones , Quemaduras/inmunología , Adhesión Celular/fisiología , Endotelio Vascular/inmunología , Femenino , Hipotensión/prevención & control , Hipoxia/prevención & control , Molécula 1 de Adhesión Intercelular , Masculino , Conejos , Factor de Necrosis Tumoral alfa/análisis
20.
J Chromatogr A ; 654(1): 1-16, 1993 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-8275174

RESUMEN

Separation of closely related solutes by steady solid-fluid counterflow is compared with differential separation in a fixed chromatographic bed. Analogous expressions for exit concentration and mean residence time in the two systems are presented. A counterpart to chromatographic resolution is derived for binary steady counterflow separations. Estimated counterflow savings in product-concentration dilution, solvent volume requirement and solid-phase volume requirement obtained with these expressions relative to comparable chromatographic operations are compared with experimental results from adsorptive, simulated moving beds. Analysis of a size-exclusion protein separation suggests counterflow substantially decreases solvent and resin usage relative to conventional, batch operation.


Asunto(s)
Cromatografía Liquida/métodos , Cromatografía Liquida/instrumentación , Proteínas/aislamiento & purificación , Solventes
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