O-linked glycosylation occurs on basic parotid salivary proline-rich proteins.

Interactions between salivary glycoproteins and many oral bacteria have been shown to depend on O-linked glycans on salivary glycoproteins. Basic proline-rich proteins form the largest group of proteins within human parotid saliva. In the present study human parotid salivary glycoproteins were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis or two-dimensional electrophoresis, electroblotted onto nitrocellulose and probed with two biotin-labelled lectins from Maclura pomifera (MPA) and Arachis hypogaea (PNA) which are specific for O-linked (galactose beta 1,3 N-Acetylgalactosamine) glycans.

Identification of cadherin tyrosine residues that are phosphorylated and mediate Shc association.

Previously, we reported association of the adaptor protein Shc through its SH2 domain with the cytoplasmic domain of the adhesion molecule cadherin (Xu et al. [1997] J. Biol.

The role of individual SH2 domains in mediating association of phospholipase C-gamma1 with the activated EGF receptor.

The two SH2 (Src homology domain 2) domains present in phospholipase C-gamma1 (PLC-gamma1) were assayed for their capacities to recognize the five autophosphorylation sites in the epidermal growth factor receptor. Plasmon resonance and immunological techniques were employed to measure interactions between SH2 fusion proteins and phosphotyrosine-containing peptides. The N-SH2 domain recognized peptides in the order of pY1173 > pY992 > pY1068 > pY1148 >> pY1086, while the C-SH2 domain recognized peptides in the order of pY992 > pY1068 > pY1148 >> pY1086 and pY1173.

Lectin binding studies of parotid salivary glycoproteins in Sjögren's syndrome.

Human parotid salivas were collected from patients with secondary Sjögren's syndrome and controls without disease or with drug-induced xerostomia. Parotid glycoproteins were separated by gradient sodium dodecyl sulphate gel electrophoresis (SDS-PAGE), electroblotted onto nitrocellulose membrane and probed with biotinylated lectins of characterised sugar specificities. The binding patterns of lectins from Maclura pomifera (MPA) and Arachis hypogaea (PNA) indicated that many parotid glycoproteins have sialylated O-linked glycans and that sialylation is not affected by disease.

Focal adhesion kinase promotes phospholipase C-gamma1 activity.

The nonreceptor tyrosine kinase FAK ("focal adhesion kinase") is a key mediator of integrin signaling events controlling cellular responses to the extracellular matrix, including spreading, migration, proliferation, and survival. Integrin-ligand interactions stimulate FAK tyrosine phosphorylation and activation of FAK signaling functions. Here evidence is presented that the FAK autophosphorylation site Tyr-397 mediates a direct interaction with the C-terminal Src homology 2 domain of phospholipase C (PLC)-gamma1 and that this is required for both adhesion-dependent association of the two molecules and increased inositol phosphate production in mouse embryo fibroblasts.

Targeting and quality of nursing home care. A five-nation study.

The objective of this study was to demonstrate that appropriate targeting and quality monitoring of institutional care of the elderly is possible using person-based information on residents of nursing homes. This cross-sectional study used Minimum Data Set (MDS) assessments of nursing home residents in 6 US states, Copenhagen, Reykjavik, and selected locations in Italy and Japan. The outcome measures were life expectancy at age 65, population over 65, percentage over 65's in nursing homes, and clinical characteristics of nursing home residents from a multinational database of RAI/MDS assessments.

Physiological requirement for both SH2 domains for phospholipase C-gamma1 function and interaction with platelet-derived growth factor receptors.

Two approaches have been utilized to investigate the role of individual SH2 domains in growth factor activation of phospholipase C-gamma1 (PLC-gamma1). Surface plasmon resonance analysis indicates that the individual N-SH2 and C-SH2 domains are able to specifically recognize a phosphotyrosine-containing peptide corresponding to Tyr 1021 of the platelet-derived growth factor (PDGF) beta receptor. To assess SH2 function in the context of the full-length PLC-gamma1 molecule as well as within the intact cell, PLC-gamma1 SH2 domain mutants, disabled by site-directed mutagenesis of the N-SH2 and/or C-SH2 domain(s), were expressed in Plcg1(-/-) fibroblasts.

Networks and groups within the genus Neisseria: analysis of argF, recA, rho, and 16S rRNA sequences from human Neisseria species.

To understand the pattern of nucleotide sequence variation among bacteria that frequently exchange chromosomal genes, we analyzed sequences of the recA, argF, and rho genes, as well as part of the small-subunit (16S) rRNA gene, from about 50 isolates of human commensal Neisseria species and the pathogenic N. meningitidis and N. gonorrhoeae.

Cubane tetrameric complexes of copper(I) chloride and bromide with triphenyl phosphite.

The crystal structures of tetra-mu 3-chloro-tetrakis[(triphenyl phosphite-P)copper(I)], [Cu4Cl4(C18H15O3P)4], and tetra-mu 3-bromo-tetrakis [(triphenyl phosphite-P)-copper(I)], [Cu4Br4(C18H15O3P)4], are described. Both have distorted 'cubane' Cu4X4 cores. Distortion of the cubane structure is reflected in X-Cu-X angles > 90 degrees and Cu-X-Cu angles < 90 degrees, and is more pronounced in the bromide complex.

Action of phosphatidylinositol-specific phospholipase Cgamma1 on soluble and micellar substrates. Separating effects on catalysis from modulation of the surface.

The kinetics of PI-PLCgamma1 toward a water-soluble substrate (inositol 1,2-cyclic phosphate, cIP) and phosphatidylinositol (PI) in detergent mixed micelles were monitored by 31P NMR spectroscopy. That cIP is also a substrate (Km = approximately 15 mM) implies a two-step mechanism (intramolecular phosphotransferase reaction to form cIP followed by cyclic phosphodiesterase activity to form inositol-1-phosphate (I-1-P)). PI is cleaved by PI-PLCgamma1 to form cIP and I-1-P with the enzyme specific activity and ratio of products (cIP/I-1-P) regulated by assay temperature, pH, Ca2+, and other amphiphilic additives.

The influence of deletion mutations on phospholipase C-gamma 1 activity.

Phospholipase C-gamma1, a substrate for many growth factor receptor and nonreceptor tyrosine kinases, produces second messenger molecules that are elements of signal transduction pathways related to cell proliferation. The influence of deletion mutations, which do not intrude on the domains required for catalytic function, on the basal activity of this enzyme is reported. Removal of the first 74 amino-terminal residues increases phospholipase C activity, while deletion of the carboxy-terminal 81 residues decreases enzyme activity.

SH2 domain-mediated activation of phospholipase Cgamma is not required to initiate Ca2+ release at fertilization of mouse eggs.

The initiation of Ca2+ release at fertilization of mammalian eggs requires inositol trisphosphate (Miyazaki et al., 1992, Science 257, 251-255), indicating that an enzyme of the phospholipase C family is probably activated. Because Ca2+ release at fertilization in echinoderm eggs is initiated by SH2 domain-mediated activation of phospholipase Cgamma (Carroll et al.

The influence of nerves on the secretion of immunoglobulin A into submandibular saliva in rats.

1. The influence of sympathetic and parasympathetic nerve stimulations on salivary secretion of immunoglobulin A (IgA) was studied in the submandibular glands of anaesthetized rats by stimulating the nerve supplies with bipolar electrodes. 2.

Tyrosine phosphorylation and proteolysis. Pervanadate-induced, metalloprotease-dependent cleavage of the ErbB-4 receptor and amphiregulin.

Enhancement of tyrosine phosphorylation in cells by the application of pervanadate, an extremely potent phosphotyrosine phosphatase inhibitor, provokes the rapid metalloprotease-dependent cleavage of ErbB-4, a transmembrane receptor tyrosine kinase. The pervanadate-induced proteolysis occurs in NIH 3T3 cells expressing transfected human ErbB-4 and in several cell lines that express endogenous ErbB-4. One product of this proteolytic event is a membrane-anchored molecule of approximately 80 kDa, which is heavily tyrosine phosphorylated and which possesses tyrosine kinase catalytic activity toward an exogenous substrate in vitro.

Analysis of platelet-derived growth factor-induced phospholipase D activation in mouse embryo fibroblasts lacking phospholipase C-gamma1.

Platelet-derived growth factor (PDGF) activates phospholipase D (PLD) in mouse embryo fibroblasts (MEFs). In order to investigate a role for phospholipase C-gamma1 (PLC-gamma1), we used targeted disruption of the Plcg1 gene in the mouse to develop Plcg1(+/+) and Plcg1(-/-) cell lines. Plcg1(+/+) MEFs treated with PDGF showed a time- and dose-dependent increase in the production of total inositol phosphates that was substantially reduced in Plcg1(-/-) cells.

Epidermal growth factor signaling and mitogenesis in Plcg1 null mouse embryonic fibroblasts.

Gene targeting techniques and early mouse embryos have been used to produce immortalized fibroblasts genetically deficient in phospholipase C (PLC)-gamma1, a ubiquitous tyrosine kinase substrate. Plcg1(-/-) embryos die at embryonic day 9; however, cells derived from these embryos proliferate as well as cells from Plcg1(+/+) embryos. The null cells do grow to a higher saturation density in serum-containing media, as their capacity to spread out is decreased compared with that of wild-type cells.

Epidermal growth factor activation of NF-kappaB is mediated through IkappaBalpha degradation and intracellular free calcium.

The transcription factor NF-kappa-B is normally sequestered in the cytoplasm by its inhibitory subunit IkappaB. Most extracellular signals activate NF-kappa-B through a mechanism involving the phosphorylation and proteasome-dependent degradation of IkappaB. EGF activates NF-kappaB in A-431 carcinoma cells, which overexpress EGF receptors and in mouse embryo fibroblasts, which have a normal complement of receptors.

Transitions across various continuing care settings.

Purpose: to compare cross-nationally the sources and rates of admission and discharge in nursing homes.

Methods: data on admission were used from the Minimum Data Set of the Resident Assessment Instrument as collected in a multi-nation database at the University of Michigan. Additional data containing longitudinal episodes were used from databases in the Netherlands, Switzerland and the USA.

RUG-III and resource allocation: comparing the relationship of direct care time with patient characteristics in five countries.

Background: resource use by different types of patients is of increasing interest to health care services all over the world. Case-mix systems that group together individuals with similar patterns of resource use have been developed to address these questions. Resource Utilization Groups version III (RUG-III) was developed in the USA to address the issue in the care of elderly people and has been validated in a number of countries.

Rehabilitation in nursing homes: a cross-national comparison of recipients.

Objective: to examine the prevalence of therapy use in nursing homes in selected countries and to describe the characteristics of nursing home residents who receive therapy. DESIGN and

Sampling: the design of the study is cross-sectional, using Minimum Data Set (MDS) assessments of nursing home residents. The sample includes all nursing home residents in six US states (n = 273491), in Copenhagen, Denmark (n = 3451), Reyjkavik, Iceland (n = 1254), and selected locations in Italy (n = 1089) and Japan (n = 1255).

Constitutive proteolysis of the ErbB-4 receptor tyrosine kinase by a unique, sequential mechanism.

The heregulin receptor tyrosine kinase ErbB-4 is constitutively cleaved, in the presence or absence of ligand, by an exofacial proteolytic activity producing a membrane-anchored cytoplasmic domain fragment of 80 kD. Based on selective sensitivity to inhibitors, the proteolytic activity is identified as that of a metalloprotease. The 80-kD product is tyrosine phosphorylated and retains tyrosine kinase activity.

Comprehensive clinical assessment in community setting: applicability of the MDS-HC.

Objective: To describe the results of an international trial of the home care version of the MDS assessment and problem identification system (the MDS-HC), including reliability estimates, a comparison of MDS-HC reliabilities with reliabilities of the same items in the MDS 2.0 nursing home assessment instrument, and an examination of the types of problems found in home care clients using the MDS-HC.

Design: Independent, dual assessment of clients of home-care agencies by trained clinicians using a draft of the MDS-HC, with additional descriptive data regarding problem profiles for home care clients.