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1.
Cryst Growth Des ; 24(8): 3277-3288, 2024 Apr 17.
Article in English | MEDLINE | ID: mdl-38659658

ABSTRACT

Precision measurement of the growth rate of individual single crystal facets (hkl) represents an important component in the design of industrial crystallization processes. Current approaches for crystal growth measurement using optical microscopy are labor intensive and prone to error. An automated process using state-of-the-art computer vision and machine learning to segment and measure the crystal images is presented. The accuracies and efficiencies of the new crystal sizing approach are evaluated against existing manual and semi-automatic methods, demonstrating equivalent accuracy but over a much shorter time, thereby enabling a more complete kinematic analysis of the overall crystallization process. This is applied to measure in situ the crystal growth rates and through this determining the associated kinetic mechanisms for the crystallization of ß-form l-glutamic acid from the solution phase. Growth on the {101} capping faces is consistent with a Birth and Spread mechanism, in agreement with the literature, while the growth rate of the {021} prismatic faces, previously not available in the literature, is consistent with a Burton-Cabrera-Frank screw dislocation mechanism. At a typical supersaturation of σ = 0.78, the growth rate of the {101} capping faces (3.2 × 10-8 m s-1) is found to be 17 times that of the {021} prismatic faces (1.9 × 10-9 m s-1). Both capping and prismatic faces are found to have dead zones in their growth kinetic profiles, with the capping faces (σc = 0.23) being about half that of the prismatic faces (σc = 0.46). The importance of this overall approach as an integral component of the digital design of industrial crystallization processes is highlighted.

2.
Data Brief ; 48: 109198, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37383827

ABSTRACT

The data presented in this article relates to the crystallisation of 8 single n-alkanes, C16H34 - C23H48 in representative diesel solvents dodecane and toluene, as well as a mixture of these 8-alkanes with a composition representative of real diesel fuel in the same solvents. For the single alkane systems, the data was collected over a range of 5 concentrations ranging from 0.09 - 0.311xi, depending upon the system, and 4 concentrations for the 8-alkane mixture, 0.1 - 0.5xi. Raw average crystallisation and dissolution points as a function of cooling rate (q) from a polythermal methodology are presented. Along with the equilibrium crystallisation and dissolution temperatures, van't Hoff fitting parameters, relative critical undercooling (uc) values as a function of q as well as the calculated values of KG and αdet.

3.
Environ Res Lett ; 14(9): 1-18, 2019 Aug 23.
Article in English | MEDLINE | ID: mdl-35340667

ABSTRACT

Social-ecological network (SEN) concepts and tools are increasingly used in human-environment and sustainability sciences. We take stock of this budding research area to further show the strength of SEN analysis for complex human-environment settings, identify future synergies between SEN and wider human-environment research, and provide guidance about when to use different kinds of SEN approaches and models. We characterize SEN research along a spectrum specifying the degree of explicit network representation of system components and dynamics. We then systematically review one end of this spectrum, what we term "fully articulated SEN" studies, which specifically model unique social and ecological units and relationships. Results show more focus on methodological advancement and applied ends. While there has been some development and testing of theories, this remains an area for future work and would help develop SENs as a unique field of research, not just a method. Authors have studied diverse systems, while mainly focused on the problem of social-ecological fit alongside a scattering of other topics. There is strong potential, however, to engage other issues central to human-environment studies. Analyzing the simultaneous effects of multiple social, environmental, and coupled processes, change over time, and linking network structures to outcomes are also areas for future advancement. This review provides a comprehensive assessment of (fully articulated) SEN research, a necessary step that can help scholars develop comparable cases and fill research gaps.

4.
Nat Sustain ; 2(7): 551-559, 2019 Jul 01.
Article in English | MEDLINE | ID: mdl-35342825

ABSTRACT

Achieving effective, sustainable environmental governance requires a better understanding of the causes and consequences of the complex patterns of interdependencies connecting people and ecosystems within and across scales. Network approaches for conceptualizing and analyzing these interdependencies offer one promising solution. Here, we present two advances we argue are needed to further this area of research: (i) a typology of causal assumptions explicating the causal aims of any given network-centric study of social-ecological interdependencies; (ii) unifying research design considerations that facilitate conceptualizing exactly what is interdependent, through what types of relationships, and in relation to what kinds of environmental problems. The latter builds on the appreciation that many environmental problems draw from a set of core challenges that re-occur across contexts. We demonstrate how these advances combine into a comparative heuristic that facilitates leveraging case-specific findings of social-ecological interdependencies to generalizable, yet context-sensitive, theories based on explicit assumptions of causal relationships.

5.
Intern Med J ; 45(11): 1179-81, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26349003

ABSTRACT

mHealth is transforming health care, yet few studies have evaluated patient and carer perceptions of the use of smartphones at the patient bedside. In this study, 70 patients and carers answered a short survey on health professionals' use of mobile devices. Half the participants were tolerant of doctors using such devices if it was work-related; others believed it was a distraction and not beneficial to patient care. Changes in practice and patient education may be needed to enable effective use of mobile devices in health.


Subject(s)
Delivery of Health Care/standards , Health Personnel/psychology , Health Personnel/standards , Patient Acceptance of Health Care/psychology , Prejudice/psychology , Telemedicine/standards , Attitude of Health Personnel , Delivery of Health Care/methods , Humans , Perception , Surveys and Questionnaires , Telemedicine/methods
6.
Plant J ; 71(2): 251-62, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22404138

ABSTRACT

Phosphoenolpyruvate carboxylase (PEPC) from developing castor oil seeds (COS) exists as two distinct oligomeric isoforms. The typical class-1 PEPC homotetramer consists of 107-kDa plant-type PEPC (PTPC) subunits, whereas the allosterically desensitized 910-kDa class-2 PEPC hetero-octamer arises from the association of class-1 PEPC with 118-kDa bacterial-type PEPC (BTPC) subunits. The in vivo interaction and subcellular location of COS BTPC and PTPC were assessed by imaging fluorescent protein (FP)-tagged PEPCs in tobacco suspension-cultured cells. The BTPC-FP mainly localized to cytoplasmic punctate/globular structures, identified as mitochondria by co-immunostaining of endogenous cytochrome oxidase. Inhibition of respiration with KCN resulted in proportional decreases and increases in mitochondrial versus cytosolic BTPC-FP, respectively. The FP-PTPC and NLS-FP-PTPC (containing an appended nuclear localization signal, NLS) localized to the cytosol and nucleus, respectively, but both co-localized with mitochondrial-associated BTPC when co-expressed with BTPC-FP. Transmission electron microscopy of immunogold-labeled developing COS revealed that BTPC and PTPC are localized at the mitochondrial (outer) envelope, as well as the cytosol. Moreover, thermolysin-sensitive BTPC and PTPC polypeptides were detected on immunoblots of purified COS mitochondria. Overall, our results demonstrate that: (i) COS BTPC and PTPC interact in vivo as a class-2 PEPC complex that associates with the surface of mitochondria, (ii) BTPC's unique and divergent intrinsically disordered region mediates its interaction with PTPC, whereas (iii) the PTPC-containing class-1 PEPC is entirely cytosolic. We hypothesize that mitochondrial-associated class-2 PEPC facilitates rapid refixation of respiratory CO(2) while sustaining a large anaplerotic flux to replenish tricarboxylic acid cycle C-skeletons withdrawn for biosynthesis.


Subject(s)
Mitochondria/enzymology , Phosphoenolpyruvate Carboxylase/metabolism , Ricinus communis/enzymology , Seeds/enzymology , Amino Acid Sequence , Ricinus communis/cytology , Ricinus communis/genetics , Cell Culture Techniques , Computational Biology , Endosperm/cytology , Endosperm/enzymology , Endosperm/genetics , Gene Expression , Isoenzymes/genetics , Isoenzymes/metabolism , Mitochondria/genetics , Molecular Sequence Data , Phosphoenolpyruvate Carboxylase/genetics , Plant Proteins/genetics , Plant Proteins/metabolism , Protein Interaction Mapping , Protein Transport , Recombinant Fusion Proteins , Seeds/cytology , Seeds/genetics , Sequence Alignment , Nicotiana/cytology , Nicotiana/enzymology , Nicotiana/genetics
7.
Front Plant Sci ; 2: 20, 2011.
Article in English | MEDLINE | ID: mdl-22639582

ABSTRACT

The endosomal sorting complex required for transport (ESCRT) consists of several multi-protein subcomplexes which assemble sequentially at the endosomal surface and function in multivesicular body (MVB) biogenesis. While ESCRT has been relatively well characterized in yeasts and mammals, comparably little is known about ESCRT in plants. Here we explored the yeast two-hybrid protein interaction network and subcellular localization of the Arabidopsis thaliana ESCRT machinery. We show that the Arabidopsis ESCRT interactome possesses a number of protein-protein interactions that are either conserved in yeasts and mammals or distinct to plants. We show also that most of the Arabidopsis ESCRT proteins examined at least partially localize to MVBs in plant cells when ectopically expressed on their own or co-expressed with other interacting ESCRT proteins, and some also induce abnormal MVB phenotypes, consistent with their proposed functional role(s) as part of the ESCRT machinery in Arabidopsis. Overall, our results help define the plant ESCRT machinery by highlighting both conserved and unique features when compared to ESCRT in other evolutionarily diverse organisms, providing a foundation for further exploration of ESCRT in plants.

8.
Tech Coloproctol ; 12(3): 225-8, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18679572

ABSTRACT

BACKGROUND: Transanal advancement flap repair (TAFR) is useful in the treatment of high transsphincteric fistulas. Initially, promising results were reported. More recent studies have indicated that TAFR fails in one out of three patients. In almost all of our patients with a failure, we have observed healing of the flap except at the site of the original internal opening. A possible explanation for this remarkable finding might be persistent inflammation in the fistulous tract, finding a way out through the original internal opening. The question is whether obliteration of the fistulous tract by local installation at a surgical adhesive, can prevent persistent inflammation to break through the original opening. The aim of this pilot study was to investigate whether concomitant instillation of BioGlue could improve the healing rate following TAFR for high transsphincteric fistulas. METHODS: Between March 2006 and April 2006 a consecutive series of eight patients (four men, four women; median age 46 years) with a high transsphincteric fistula underwent TAFR after instillation of BioGlue in the fistulous tract. All patients were seen in the outpatient department for postoperative evaluation. RESULTS: Fistula healing was observed in only one patient (12.5%). All other patients experienced one or more of the following complications: prolonged severe pain (n=5), discharge of great amounts of purulent liquid from the external opening (n=3) and abscess formation (n=2), necessitating incision and drainage. Because of this unexpected outcome we decided to terminate the study prematurely. CONCLUSIONS: Our findings indicate that obliteration of the fistulous tract with BioGlue adversely affects the outcome of TAFR for high transsphincteric fistulas.


Subject(s)
Proteins/adverse effects , Rectal Fistula/surgery , Surgical Flaps , Wound Healing/drug effects , Adult , Combined Modality Therapy , Digestive System Surgical Procedures , Female , Humans , Instillation, Drug , Male , Middle Aged , Proteins/administration & dosage
9.
J Dairy Sci ; 86(11): 3787-95, 2003 Nov.
Article in English | MEDLINE | ID: mdl-14672211

ABSTRACT

A viable and cost-effective approach to managing P on dairy farms is to minimize excess P in diets, which in turn leads to less excretion of P in manure without impairing animal performance. A questionnaire survey was conducted, coupled with on-site feed and fecal sample collection and analysis on dairy farms in New York, Pennsylvania, Delaware, Maryland, and Virginia. The purpose was to assess dietary P levels and to identify critical control points pertaining to P feeding management. Survey responses, 612 out of 2500 randomly selected farms, revealed a wide range of dietary P concentrations for lactating cows, from 3.6 to 7.0 g/kg of feed DM. The mean was 4.4 g/kg, which was 34% above the level recommended by the NRC for 27.9 kg milk/d, the mean milk yield in the survey. Higher P concentrations in diets were not associated with higher milk yields (n = 98, R2 = 0.057 for the survey farms; n = 92, R2 = 0.043 for farms selected for on-site sampling). However, higher dietary P led to higher P excretion in feces (n = 75, R2 = 0.429), with much of the increased fecal P being water soluble. Phosphorus concentrations in diet samples matched closely with P concentrations in formulated rations, with 67% of the feed samples deviating <10% from the formulations. On 84% of the survey farms, ration formulation was provided by professionals rather than producers themselves. Most producers were feeding more P than cows needed because it was recommended in the rations by these consultants. In conclusion, P fed to lactating cows averaged 34% above NRC recommendations; to reduce excess dietary P, ration formulation is the critical control point.


Subject(s)
Animal Feed/analysis , Environmental Pollution/prevention & control , Feces/chemistry , Phosphorus, Dietary/administration & dosage , Phosphorus/analysis , Animal Husbandry/methods , Animal Nutritional Physiological Phenomena , Animals , Cattle , Dairying , Diet , Manure , Nutritional Requirements , Soil Pollutants/analysis , Surveys and Questionnaires , Water Pollution, Chemical/prevention & control
10.
J Clin Microbiol ; 39(1): 119-28, 2001 Jan.
Article in English | MEDLINE | ID: mdl-11136759

ABSTRACT

A means for distinguishing between clinical isolates of Renibacterium salmoninarum that is based on the PCR amplification of length polymorphisms in the tRNA intergenic spacer regions (tDNA-ILPs) was investigated. The method used primers specific to nucleotide sequences of R. salmoninarum tRNA genes and tRNA intergenic spacer regions that had been generated by using consensus tRNA gene primers. Twenty-one PCR products were sequenced from five isolates of R. salmoninarum from the United States, England, and Scotland, and four complete tRNA genes and spacer regions were identified. Sixteen specific PCR primers were designed and tested singly and in all possible pairwise combinations for their potential to discriminate between isolates from recent clinical outbreaks of bacterial kidney disease (BKD) in the United Kingdom. Fourteen of the isolates were cultured from kidney samples taken from fish displaying clinical signs of BKD on five farms, and some of the isolates came from the same farm and at the same time. The tDNA-ILP profiles separated 22 clinical isolates into nine groups and highlighted that some farms may have had more than one source of infection. The grouping of isolates improved on the discriminatory power of previously reported typing methods based on randomly amplified polymorphic DNA analysis and restriction fragment length profiles developed using insertion sequence IS994. Our method enabled us to make divisions between closely related clinical isolates of R. salmoninarum that have identical exact tandem repeat (ETR-A) loci, rRNA intergenic spacer sequences, and IS994 profiles.


Subject(s)
Actinomycetales Infections/veterinary , Actinomycetales/classification , DNA, Intergenic/genetics , Fish Diseases/microbiology , RNA, Transfer/genetics , Salmonidae , Actinomycetales/genetics , Actinomycetales/isolation & purification , Animals , Aquaculture , DNA, Bacterial/genetics , Genes, Bacterial , Genetic Variation , Molecular Sequence Data , Polymerase Chain Reaction , Random Amplified Polymorphic DNA Technique , Sequence Analysis, DNA , Tandem Repeat Sequences/genetics
11.
Antonie Van Leeuwenhoek ; 78(1): 51-61, 2000 Jul.
Article in English | MEDLINE | ID: mdl-11016696

ABSTRACT

The nucleotide sequences of the rRNA genes and the 5' flanking region were determined for R. salmoninarum ATCC 33209T from overlapping products generated by PCR amplification from the genomic DNA. Comparison of the sequences with rRNA genes from a variety of bacteria demonstrated the close relatedness between R. salmoninarum and the high G+C group of the actinobacteria, in particular, Arthrobacter species. A regulatory element within the 5' leader of the rRNA operon was identical to an element, CL2, described for mycobacteria. PCR, DNA sequence analysis, and DNA hybridisation were performed to examine variation between isolates from diverse sources which represented the four 16S-23S rRNA intergenic spacer sequevars previously described for R. salmoninarum. Two 23S-5S rRNA intergenic spacer sequevars of identical length were found. DNA hybridisation using probes complementary to 23S rDNA and 16S rDNA identified two rRNA operons which were identical or nearly identical amongst 40 isolates sourced from a variety of countries.


Subject(s)
Conserved Sequence , DNA, Ribosomal/genetics , Gram-Positive Asporogenous Rods, Regular/genetics , Operon , RNA, Ribosomal/genetics , Actinomycetales/genetics , Base Sequence , Gene Dosage , Genetic Variation , Molecular Sequence Data , Phylogeny , Polymerase Chain Reaction , RNA, Ribosomal, 16S/genetics , RNA, Ribosomal, 23S/genetics , RNA, Ribosomal, 5S/genetics , Restriction Mapping , Sequence Analysis, DNA
12.
Gene ; 244(1-2): 97-107, 2000 Feb 22.
Article in English | MEDLINE | ID: mdl-10689192

ABSTRACT

Renibacterium salmoninarum, a slowly growing, Gram-positive bacterium, is responsible for bacterial kidney disease in salmonid fishes world-wide. To date, no mobile genetic elements have been reported for this pathogen. Here, we describe the first insertion sequence (IS) identified from R. salmoninarum. This element, IS994, has a significant predicted amino acid sequence homology (64.8 and 71.9%) to the two open reading frames encoding the transposase of IS6110 of Mycobacterium tuberculosis. Protein parsimony and protein distance matrix analyses show that IS994 is a member of group IS51 of the IS3 family. From a conservative estimate, there are at least 17 chromosomal insertions of IS994 or closely related elements. Sequence analysis of seven of these loci reveals single nucleotide polymorphisms throughout the element (including the terminal inverted repeats), a 15bp insertion in three of the seven loci, and an absence of flanking direct repeats or conserved insertion site. Restriction fragment length polymorphism analysis of XbaI-digested chromosomal DNA shows variations among European and North American isolates, indicating that IS994 may be a useful molecular marker for epizootiological studies.


Subject(s)
DNA Transposable Elements/genetics , Fish Diseases/microbiology , Gram-Positive Bacteria/genetics , Amino Acid Sequence , Animals , Base Sequence , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , Genetic Variation , Geography , Gram-Positive Bacteria/chemistry , Gram-Positive Bacteria/isolation & purification , Gram-Positive Bacterial Infections/microbiology , Gram-Positive Bacterial Infections/veterinary , Molecular Sequence Data , Open Reading Frames , Phylogeny , Polymorphism, Restriction Fragment Length , Salmon/microbiology , Sequence Alignment , Sequence Analysis, DNA , Sequence Homology, Amino Acid , Sequence Homology, Nucleic Acid , Species Specificity , Transposases/genetics
13.
Appl Environ Microbiol ; 66(1): 435-8, 2000 Jan.
Article in English | MEDLINE | ID: mdl-10618262

ABSTRACT

The molecular diversity among 60 isolates of Renibacterium salmoninarum which differ in place and date of isolation was investigated by using randomly amplified polymorphic DNA (RAPD) analysis. Isolates were grouped into 21 banding patterns which did not reflect the biological source. Four 16S-23S rRNA intergenic spacer (ITS1) sequence variations and two alleles of an exact tandem repeat locus, ETR-A, were the bases for formation of distinct groups within the RAPD clusters. This study provides evidence that the most common ITS1 sequence variant, SV1, possesses two copies of a 51-bp repeat unit at ETR-A and has been widely dispersed among countries which are associated with mainstream intensive salmonid culture.


Subject(s)
Genetic Variation , Micrococcaceae/genetics , Random Amplified Polymorphic DNA Technique , Salmonidae/microbiology , Animals , Fish Diseases/microbiology , Gram-Positive Bacterial Infections/microbiology , Gram-Positive Bacterial Infections/veterinary , Micrococcaceae/growth & development , Micrococcaceae/isolation & purification , Molecular Sequence Data , RNA, Ribosomal, 16S/genetics , RNA, Ribosomal, 23S/genetics , Tandem Repeat Sequences/genetics
14.
Clin Perinatol ; 25(1): 63-78, 1998 Mar.
Article in English | MEDLINE | ID: mdl-9523075

ABSTRACT

The use of sedation, muscle relaxation, or analgesia in the management of ventilated neonates has been controversial. Many neonatologists face a difficult decision on whether or not to use a muscle relaxant on a ventilated infant. This article reviews neonatal physiology and pharmacology, drug administration, absorption, distribution, and certain selected sedatives and analgesics. The muscle relaxants, financial issues, and family issues are also discussed.


Subject(s)
Analgesics, Opioid/therapeutic use , Benzodiazepines/therapeutic use , Infant, Newborn/physiology , Muscle Relaxants, Central/therapeutic use , Respiration, Artificial , Analgesia , Analgesics, Opioid/metabolism , Benzodiazepines/metabolism , Drug Costs , Humans , Hypnotics and Sedatives/therapeutic use , Neonatal Abstinence Syndrome/therapy , Respiration, Artificial/adverse effects
15.
Dev Dyn ; 209(3): 261-8, 1997 Jul.
Article in English | MEDLINE | ID: mdl-9215641

ABSTRACT

Extracellular proteases may play an important role in the regulation of cell migration and remodeling of the extracellular matrix during development. In this study, we have examined the embryonic avian heart for the expression of matrix metalloproteases. The 72-kDa type IV collagenase, MMP-2, was detected in extracts of whole hearts and showed a modest increase in amount over time. This increase in enzyme activity corresponded to a small increase in the steady-state level of mRNA for this enzyme. A more dramatic increase was seen in the amount of the 66-kDa activated form of this enzyme as development progressed, suggesting that the process of activation, rather than enzyme synthesis, may be the important regulatory step in this system. Coincident with the change in the level of active MMP-2 was a significant increase in the expression of the MMP-2 activator, MT-MMP, between stages 12 and 24. The message for MMP-2 was expressed by the endocardium of the cushion tissues which was undergoing an epithelial-mesenchymal transition, and by the migrating mesenchymal cells, suggesting a role for this protease in regulating cell motility and matrix invasion. In older staged hearts, the cells of the differentiating valves expressed high levels of MMP-2 which may be important for the final remodeling events in this region.


Subject(s)
Gelatinases/genetics , Heart Valves/embryology , Heart Valves/enzymology , Metalloendopeptidases/genetics , Animals , Chick Embryo , Gelatinases/metabolism , Gene Expression Regulation, Developmental/physiology , Gene Expression Regulation, Enzymologic/physiology , In Situ Hybridization , Matrix Metalloproteinase 2 , Metalloendopeptidases/metabolism , Polymerase Chain Reaction , Quail , RNA, Messenger/analysis
16.
Infect Dis Obstet Gynecol ; 1(5): 246-8, 1994.
Article in English | MEDLINE | ID: mdl-18472882

ABSTRACT

BACKGROUND: Disseminated herpetic infections during pregnancy have been reported in the literature. CASE: This case presentation describes a pregnant patient who presented with fever, elevated liver enzymes, and upper abdominal tenderness and succumbed from fulminant herpetic hepatitis. CONCLUSION: Early diagnosis and treatment are essential because of the high mortality rate.

17.
Infect Dis Obstet Gynecol ; 2(1): 30-3, 1994.
Article in English | MEDLINE | ID: mdl-18475363

ABSTRACT

OBJECTIVE: We evaluated a new affinity membrane strip test for the diagnosis of herpetic genital infections. Test strip results, which are available by immunoassay in 30 min without the need for special equipment, were compared with the results of viral culture. METHODS: Twenty-eight female patients with vulvar lesions thought to be due to genital herpes simplex virus (HSV) infection were tested. The affinity membrane strip was applied to the genital lesion. Dacron swabs were then applied to the lesions and the swab contents cultured for HSV. For the immunoassay, the test strip was immersed in peroxidase-labeled antibodies specific for HSV type 2 (HSV-2), incubated, washed, and developed in the substrate tetramethylbenzidine. Positive reactions appeared as intense blue spots roughly the shape and size of the lesion. Sensitivity and specificity of the test were determined using the results of viral cultures as the standard. RESULTS: The lesions of 8 patients yielded positive strips that correlated with positive cultures. The lesions of 6 patients produced positive strips but the cultures were negative. None of the patients whose lesions yielded negative strips had positive cultures. The lesions of 14 patients produced negative strips and negative cultures. Strips and viral cultures from 10 control patients (no lesions) were negative. Sensitivity and specificity were 100% and 70%, respectively. Positive (PPV) and negative (NPV) predictive values were 57% and 100%, respectively. The accuracy was 78%. CONCLUSIONS: The affinity membrane test was extremely sensitive in detecting herpetic genital infection compared with viral culture. The specificity was lower, resulting from false positives based on negative cultures. However, negative cultures may occur in the presence of disease, depending in part on the type of lesion. Thus, specificity may be higher than this preliminary study indicates, and more elaborate search for virus including serologic studies as well as larger groups of patients may be needed to refine this evaluation. With further testing and development, this membrane affinity test for herpes may yield a valuable adjunct to clinical diagnosis of this infection.

18.
Development ; 118(3): 931-9, 1993 Jul.
Article in English | MEDLINE | ID: mdl-8076527

ABSTRACT

The expression of the serine protease urokinase is elevated during the epithelial-mesenchymal transformation of the endocardium in the developing avian heart. Elevated urokinase expression is associated with the migrating mesenchymal cells of the atrioventricular canal and bulbotruncus and not the myocardium. Treatment of isolated endocardial-derived mesenchymal cells with phosphatidyinositol-specific phospholipase C released urokinase and its receptor from the cell surface and caused significant alterations in cell morphology and motility. Likewise inhibition of urokinase synthesis by treatment of cells with antisense oligonucleotides also inhibited the migration and motility of the endocardial-derived cells. These results suggest an important role for this enzyme in cell-matrix interactions and cell migration during development.


Subject(s)
Endocardium/embryology , Mesoderm/drug effects , Muscle Proteins/physiology , Oligonucleotides, Antisense/pharmacology , Phosphoric Diester Hydrolases/pharmacology , Receptors, Cell Surface/antagonists & inhibitors , Serine Proteinase Inhibitors/pharmacology , Urokinase-Type Plasminogen Activator/physiology , Animals , Base Sequence , Cell Adhesion/drug effects , Cell Movement/drug effects , Cells, Cultured , Coturnix/embryology , Endocardium/cytology , Endocardium/enzymology , Enzyme Induction/drug effects , Mesoderm/cytology , Mesoderm/enzymology , Molecular Sequence Data , Muscle Proteins/biosynthesis , Muscle Proteins/genetics , Organ Culture Techniques , Phosphatidylinositol Diacylglycerol-Lyase , Receptors, Urokinase Plasminogen Activator , Surface Properties , Urokinase-Type Plasminogen Activator/biosynthesis , Urokinase-Type Plasminogen Activator/genetics
19.
Dev Biol ; 155(2): 442-51, 1993 Feb.
Article in English | MEDLINE | ID: mdl-8432398

ABSTRACT

Early events in cardiovascular morphogenesis are characterized by cell migrations and extensive tissue remodeling. We are interested in the role played by the extracellular serine protease urokinase in these events. Elevated urokinase activity and mRNA levels have been shown to be associated with the onset of ventricular trabeculation and mesenchymal cell migration in the endocardial cushion tissues of the atrioventricular canal and the outflow tract of the quail embryo. In this study, urokinase production by isolated endocardial-derived cells was found to be affected by the composition of the matrix to which the cells were exposed. Interaction of cells with a 45-kDa gelatin-binding fragment of fibronectin upregulated the production of urokinase by nearly threefold. This increase in urokinase activity had profound influences on cell motility and spreading.


Subject(s)
Endocardium/enzymology , Urokinase-Type Plasminogen Activator/biosynthesis , Animals , Cell Movement , Cells, Cultured , Culture Techniques , Electrophoresis, Polyacrylamide Gel , Endocardium/cytology , Endocardium/embryology , Fibronectins/metabolism , Quail , Substrate Specificity , Urokinase-Type Plasminogen Activator/antagonists & inhibitors
20.
Dev Dyn ; 194(3): 193-7, 1992 Jul.
Article in English | MEDLINE | ID: mdl-1467555

ABSTRACT

Early events in the morphogenesis of the axial skeleton involve an epithelial-mesenchymal transformation of the somites. Cells of the ventromedial wall of the somite (the sclerotome) migrate to regions surrounding the notochord and neural tube and condense to form the cartilage model of the vertebrae. Urokinase activity in the axial region of the quail embryo trunk was found to increase during these stages. In situ hybridization localized urokinase mRNA expression in this region and suggests an important role for this protease in the process of cell migration and matrix remodeling during development of the axial skeleton.


Subject(s)
Coturnix/embryology , Embryo, Nonmammalian/metabolism , Mesoderm/physiology , Urokinase-Type Plasminogen Activator/metabolism , Animals , Densitometry , Embryonic and Fetal Development , Epithelium/embryology , In Situ Hybridization , RNA, Messenger/metabolism , Urokinase-Type Plasminogen Activator/genetics
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