Fibroblast transgelin and smooth muscle SM22alpha are the same protein, the expression of which is down-regulated in many cell lines

In this report we investigate the expression and relationship of transgelin (Tg), a transformation and shape-change sensitive actin gelling protein found in fibroblasts and smooth muscle [Shapland et al., 1988: J. Cell. Biol. 107:153-161; Shapland et al., 1993: J. Cell. Biol. 121:1065-1073], to SM22alpha, a smooth muscle protein of unknown function [Lees-Millar et al., 1987: J. Biol. Chem. 262:2988-2993; Solway et al., 1995: J. Biol. Chem. 270:13460-13469]. To clarify their relationship we have cloned and sequenced the cDNA encoding Tg from cultures of rat embryo fibroblasts. The sequences of fibroblast Tg and the smooth muscle isoform SM22 are identical [Prinjha et al., 1994: Cell Motil. Cytoskeleton 28:243-255; Shanahan et al., 1993: Circ. Res. 73:193-204; Solway et al., 1995]. These data, coupled with our immunoblot analysis and previous observations [Shapland et al., 1988; Shapland et al., 1993], demonstrate that Tg expression is not restricted to smooth muscle since this protein is also present in normal mesenchymal cells. However, we also show that Tg, although present in secondary cultures of mouse and rat embryo fibroblasts, is absent in many apparently normal fibroblast cell lines. Tg down-regulation may therefore be an early and sensitive marker for the onset of transformation. A functional role for Tg is unlikely to directly involve Ca2+ since it neither contains a functional EF hand nor binds 45Ca2+.

A novel nervous system beta subunit that downregulates human large conductance calcium-dependent potassium channels

The pore-forming alpha subunits of many ion channels are associated with auxiliary subunits that influence channel expression, targeting, and function. Several different auxiliary (beta) subunits for large conductance calcium-dependent potassium channels of the Slowpoke family have been reported, but none of these beta subunits is expressed extensively in the nervous system. We describe here the cloning and functional characterization of a novel Slowpoke beta4 auxiliary subunit in human and mouse, which exhibits only limited sequence homology with other beta subunits. This beta4 subunit coimmunoprecipitates with human and mouse Slowpoke. beta4 is expressed highly in human and monkey brain in a pattern that overlaps strikingly with Slowpoke alpha subunit, but in contrast to other Slowpoke beta subunits, it is expressed little (if at all) outside the nervous system. Also in contrast to other beta subunits, beta4 downregulates Slowpoke channel activity by shifting its activation range to more depolarized voltages and slowing its activation kinetics. beta4 may be important for the critical roles played by Slowpoke channels in the regulation of neuronal excitability and neurotransmitter release.

Mutational analysis of the Wolfram syndrome gene in two families with chromosome 4p-linked bipolar affective disorder

Bipolar affective disorder (BPAD) is a complex disease with a significant genetic component. Heterozygous carriers of Wolfram syndrome (WFS) are at increased risk of psychiatric illness. A gene for WFS (WFS1) has recently been cloned and mapped to chromosome 4p, in the general region we previously reported as showing linkage to BPAD. Here we present sequence analysis of the WFS1 coding sequence in five affected individuals from two chromosome 4p-linked families. This resulted in the identification of six polymorphisms, two of which are predicted to change the amino acid sequence of the WFS1 protein, however none of the changes segregated with disease status. Am. J. Med. Genet. (Neuropsychiatr. Genet.) 96:158-160, 2000.

Bcl-2: bax and bcl-2: Bcl-x ratios by image cytometric quantitation of immunohistochemical expression in ovarian carcinoma: correlation with prognosis

Bcl-2 is a proto-oncogene which is involved in prolonging cell survival by inhibiting programmed cell death. Bax and bcl-x are members of the bcl-2 family; when overexpressed, they can counteract the ability of bcl-2 to inhibit apoptosis. This suggests a model in which the ratios of bcl-2 to bax and bcl-x can be used to determine response to therapy and prognosis. The expression of bcl-2, bax and bcl-x was studied in 50 ovarian carcinomas. The percentage of positive area immunostained (PPA) in the nucleus and cytoplasm of each ovarian carcinoma was quantitated in 15 high power fields by image cytometry. The ratios were obtained by dividing the PPA of bcl-2 by the PPA of bax and bcl-x. 17 of 50 ovarian carcinomas (34%) stained positively for bcl-2, 39 for bax (78%) and 47 for bcl-x (94%). Although there is no significant statistical correlation between expression of bcl-2, bax or bcl-x and grade (P = 0.15; P = 0. 47; P = 0.56), stage (P = 0.71; P = 0.6; P = 0.42), and overall or disease-free survival (P = 0.26; P = 0.55; P = 0.16), increased bcl-2 expression was demonstrated in patients with shortened overall and disease-free survival. Also, increased expression of bax and bcl-x was associated with increased overall and disease-free survival. Bcl-2:bax and bcl-2:bcl-x ratios less than 1 are associated with survival advantage, although not statistically significant (P = 0.83; P = 0.93). Image cytometric measurement of bcl-2, bax, and bcl-x expression is feasible. There is a tendency for their expression to correlate with prognosis in ovarian carcinomas.

The development of competency standards for specialist critical care nurses

In defining the contemporary role of the specialist nurse it is necessary to challenge the concept of nursing as merely a combination of skills and knowledge. Nursing must be demonstrated and defined in the context of client care and include the broader notions of professional development and competence. This qualitative study sought to identify the competency standards for nurse specialists in critical care and to articulate the differences between entry-to-practice standards and the advanced practice of specialist nurses. Over 800 hours of specialist critical care nursing practice were observed and grouped into 'domains' or major themes of specialist practice using a constant comparison qualitative technique. These domains were further refined to describe attributes of the registered nurses which resulted in effective and/or superior performance (competency standards) and to provide examples of performance (performance criteria) which met the defined standard. Constant comparison of the emerging domains, competency standards and performance criteria to observations of specialist critical care practice, ensured the results provided a true reflection of the specialist nursing role. Data analysis resulted in 20 competency standards grouped into six domains: professional practice, reflective practice, enabling, clinical problem solving, teamwork, and leadership. Each of these domains is comprised of between two and seven competency standards. Each standard is further divided into component parts or 'elements' and the elements are illustrated with performance criteria. The competency standards are currently being used in several Australian critical care educational programmes and are the foundation for an emerging critical care credentialling process. They have been viewed with interest by a variety of non-critical care specialty groups and may form a common precursor from which further specialist nursing practice assessment will evolve.

Neuregulin in neuron/glial interactions in the central nervous system. GGF2 diminishes autoimmune demyelination, promotes oligodendrocyte progenitor expansion, and enhances remyelination

Glial growth factor 2 (GGF2) is a neuronal signal that promotes the proliferation and survival of the oligodendrocyte, the myelinating cell of the central nervous system (CNS). This study has focused on recombinant human GGF2 (rhGGF2) and it's potential to affect clinical recovery and repair to damaged myelin in chronic relapsing experimental autoimmune encephalomyelitis (EAE) in the mouse, a major animal model for the human demyelinating disease, multiple sclerosis (MS). Mice with EAE were treated with rhGGF2 during both the acute and relapsing phases, and GGF2 treatment led to delayed signs, decreased severity and resulted in statistically significant reductions in relapse rate. Further, rhGGF2-treated groups displayed CNS lesions with more remyelination than in controls. This correlated with increased expression of myelin basic protein exon 2, a marker for remyelination, and with an increase of the regulatory cytokine, IL-10. Thus, a beneficial effect of a neurotrophic growth factor has been demonstrated upon the clinical, pathologic and molecular manifestations of autoimmune demyelination, an effect that was associated with increased expression of a Th2 cytokine. rhGGF2 treatment may represent a novel approach to the treatment of MS (Cannella et al., 1998).

Data mining parasite genomes: haystack searching with a computer

A number of genomes of parasitic organisms are presently being sequenced in the public domain, including Plasmodium falciparum, Leishmania major and Trypanosoma brucei with the likelihood of at least expressed sequence tag (EST) projects for several filarial and apicomplexan species. The early and timely release of sequence data to the community via the World Wide Web (www), and the public databases, (EMBL and GENBANK), forms an invaluable resource. Data mining, or 'haystack searching' this resource is becoming more fruitful to all members of the scientific community as the volume of data, diversity of genomes sampled, and accessibility increase.

The complete nucleotide sequence of chromosome 3 of Plasmodium falciparum

Analysis of Plasmodium falciparum chromosome 3, and comparison with chromosome 2, highlights novel features of chromosome organization and gene structure. The sub-telomeric regions of chromosome 3 show a conserved order of features, including repetitive DNA sequences, members of multigene families involved in pathogenesis and antigenic variation, a number of conserved pseudogenes, and several genes of unknown function. A putative centromere has been identified that has a core region of about 2 kilobases with an extremely high (adenine + thymidine) composition and arrays of tandem repeats. We have predicted 215 protein-coding genes and two transfer RNA genes in the 1,060,106-base-pair chromosome sequence. The predicted protein-coding genes can be divided into three main classes: 52.6% are not spliced, 45.1% have a large exon with short additional 5' or 3' exons, and 2.3% have a multiple exon structure more typical of higher eukaryotes.

Schwann cell-derived Desert hedgehog controls the development of peripheral nerve sheaths

We show that Schwann cell-derived Desert hedgehog (Dhh) signals the formation of the connective tissue sheath around peripheral nerves. mRNAs for dhh and its receptor patched (ptc) are expressed in Schwann cells and perineural mesenchyme, respectively. In dhh-/- mice, epineurial collagen is reduced, while the perineurium is thin and disorganized, has patchy basal lamina, and fails to express connexin 43. Perineurial tight junctions are abnormal and allow the passage of proteins and neutrophils. In nerve fibroblasts, Dhh upregulates ptc and hedgehog-interacting protein (hip). These experiments reveal a novel developmental signaling pathway between glia and mesenchymal connective tissue and demonstrate its molecular identity in peripheral nerve. They also show that Schwann cell-derived signals can act as important regulators of nerve development.

Do patients' ethnic and social factors influence the use of do-not-resuscitate orders?

OBJECTIVES

To determine whether ethnic and other social factors affect how frequently do-not-resuscitate (DNR) orders are written, the timing of DNR orders, or patient involvement in the DNR decision.

DESIGN

Retrospective cohort.

METHODS

Patients who died in one urban teaching hospital on the medicine, cardiology, or family practice service during 1988 were eligible; 288 were included in the analyses. Chi-square tests and logistic regression were used to examine frequency of DNR orders and patient involvement; analysis of variance and linear regression were used to examine timing of the DNR orders.

RESULTS

Non-whites were more likely than whites to have DNR orders (OR 1.76; 95% CI, 1.09-2.84) but timing of the DNR order did not vary significantly by race/ethnicity. Patients who spoke English fluently were more likely to be involved in the DNR decision than those who did not (OR 1.28; 95% CI, 1.01-1.61). Patients with documented human immunodeficiency virus were more likely than uninfected patients to have DNR orders (OR 3.51; 95% CI, 1.36-9.02), to be involved in the decision (OR 10.11; 95% CI, 4.87-21.00); and to have DNR orders written earlier (P = 0.02). Alcoholic patients were more likely than non-alcoholics to have DNR orders (OR 1.17; 95% CI, 1.04-1.33).

CONCLUSIONS

Ethnic and other social factors do appear to play a role in DNR decisions. It needs to be determined if these differences are due to patient preferences or clinician characteristics.

Epidermal growth factor receptor activation is localized within low-buoyant density, non-caveolar membrane domains

Increasing evidence for the organization of cell-surface proteins and lipids into different detergent-insoluble rafts led us to investigate epidermal growth factor (EGF) receptor activation in the plasma membranes of A431 carcinoma cells, using a combination of cell fractionation and immunoprecipitation techniques. Density-gradient centrifugation of sodium carbonate cell extracts revealed that the vast majority of both stimulated and unstimulated EGF receptors were concentrated in a caveolin-rich light membrane (CLM) fraction, with the biochemical characteristics of detergent-insoluble glycolipid-rich domains (DIGs). However, ultrastructural analysis of the CLM fraction revealed that it contained a heterogeneous collection of vesicles, some with sizes greater than that expected for individual caveolae. Experiments with detergent-solubilized cells and isolated CLMs indicated that, in contrast with caveolin, EGF receptors were unlikely to be localized to DIG domains. Furthermore, immunoisolation of caveolin from CLMs revealed that EGF receptor activation occurs in a compartment distinct from caveolae. Similarly, using an anti-(EGF receptor) antibody, the bulk of the cellular caveolin was not co-immunoprecipitated from CLMs, thereby confirming that these two proteins reside in separate membrane domains. The deduction that caveolar signalling and EGF receptor activation occur in separable rafts argues for a multiplicity of signal transduction compartments within the plasma membrane. In addition, by demonstrating that EGF receptor activation is compartmentalized within low-density, non-caveolar regions of the plasma membrane, it is also shown that the co-localization of proteins in a CLM fraction is insufficient to prove caveolar localization.

Sex and androgenic steroid receptor expression in hepatic adenomas

Sex hormones and anabolic-androgenic steroids are implicated in the development and progression of hepatic adenomas (HA). We studied the expression of their receptors in HA and adjacent liver. Archival tissue sections of 27 HA (16 resections, four needle biopsies, seven aspirations) from 18 patients, and the adjacent liver, were immunostained with monoclonal antibody to estrogen receptor (ER, 1/80) (Dako, Carpinteria, CA), progesterone receptor (PR, 1/50) (BioGenex, San Ramon, CA), and androgen receptor (AR, 1/80) (BioGenex). An avidin-biotin complex technique was used with microwave antigen retrieval. Nuclear expression was assessed as 1+ to 3+ intensity, with semiquantitation of the percentage of nuclei immunopositive. Five percent or more nuclei immunopositive was regarded as positive. The 18 patients included 16 females of 34 years mean age (range, 16 to 49) with an available history of oral contraceptives in five; the two men were 24 and 30 years, with no history of androgenic steroids. ER, PR, and AR were present in seven (26%) (1+/-2+ intensity, 5% to 10% of nuclei) of HA, seven (26%) (1+/-2+ intensity, 5% to 30% of nuclei) and nine (33%) (1+/-3+ intensity, 5% to 80% of nuclei), respectively. In the adjacent liver in 11 cases, there were one (9%) ER, (2+ intensity, 5% of nuclei), four (36%) PR (1+/-2+ intensity, 5% to 20% of nuclei), and two (18%) AR (2+/-3+ intensity, 10% of nuclei). Receptors are present and may mediate the action of sex hormones or androgenic steroids on HA and adjacent liver, but in less than one third of patients. This may have therapeutic implications.

A long-range restriction map across 3 Mb of the chromosome 11 breakpoint region of a translocation linked to schizophrenia: localization of the breakpoint and the search for neighbouring genes

A balanced t(1;11)(q42.1;q14.3) translocation segregates with schizophrenia and related mental illness in a single large Scottish pedigree. We have constructed a long-range restriction map covering at least 3 Mb of the chromosome 11 breakpoint region and conducted searches for genes whose expression could be altered by the translocation, resulting in schizophrenia. Novel transcribed sequences of unknown function clustered around putative CpG islands, located approximately 500 kb and 700 kb above the breakpoint, represent the only evidence to date for expressed genes within the mapped region.

The neuregulin, glial growth factor 2, diminishes autoimmune demyelination and enhances remyelination in a chronic relapsing model for multiple sclerosis

Glial growth factor 2 (GGF2) is a neuronal signal that promotes the proliferation and survival of the oligodendrocyte, the myelinating cell of the central nervous system (CNS). The present study examined whether recombinant human GGF2 (rhGGF2) could effect clinical recovery and repair to damaged myelin in chronic relapsing experimental autoimmune encephalomyelitis (EAE) in the mouse, a major animal model for the human demyelinating disease, multiple sclerosis. Mice with EAE were treated with rhGGF2 during both the acute and relapsing phases. Clinically, GGF2 treatment delayed signs, decreased severity, and resulted in statistically significant reductions in relapse rate. rhGGF2-treated groups displayed CNS lesions with more remyelination than in controls. This correlated with increased mRNA expression of myelin basic protein exon 2, a marker for remyelination, and with an increase in the CNS of the regulatory cytokine, interleukin 10, at both the RNA and protein levels. Thus, a beneficial effect of a neurotrophic growth factor has been demonstrated on the clinical, pathologic, and molecular manifestations of autoimmune demyelination, an effect that was associated with increased expression of a T helper 2 cytokine. rhGGF2 treatment may represent a novel approach to the treatment of multiple sclerosis.

Phosphatidylinositol 4-phosphate synthesis in immunoisolated caveolae-like vesicles and low buoyant density non-caveolar membranes

This study examined phosphatidylinositol 4-phosphate (PtdIns4P) synthesis in caveolae that have been suggested to be discrete signaling microdomains of the plasma membrane and are enriched in the marker protein caveolin. Caveolin-rich light membranes (CLMs) were isolated from A431 cells by detergent-free, discontinuous density-gradient centrifugation method. The CLM fraction was separated from the bulk of the cellular protein and was greatly enriched in PtdIns, PtdIns4P, and phosphatidylinositol 4, 5-bisphosphate (PtdIns(4,5)P2) and an adenosine-sensitive type II PtdIns 4-kinase activity. Preparation of CLMs by an OptiPrep-based cell fractionation procedure confirmed the co-localization of PtdIns 4-kinase and caveolin. Electron microscopy confirmed that an anti-caveolin antiserum immunopurified vesicles from CLMs that were within the size range described for caveolae in other systems. Co-immunoprecipitated PtdIns 4-kinase activity could utilize endogenous PtdIns, present within the caveolae-like vesicles, to produce PtdIns4P. The addition of recombinant phosphatidylinositol transfer protein increased PtdIns 4-kinase activity both in immunoisolated caveolae and CLMs. However, less than 1% of the total cellular PtdIns and PtdIns 4-kinase activity was present in caveolae-like vesicles, indicating that non-caveolar light membrane rafts are the main site for cellular PtdIns4P production.

Immediate breast reconstruction for stage III breast cancer using transverse rectus abdominis musculocutaneous (TRAM) flap

BACKGROUND

The management of state III breast cancer is challenging; it often includes multimodal treatment with systemic therapy and/or radiation therapy and surgery. Immediate breast reconstruction has not traditionally been performed in these patients. We review the results of immediate transverse rectus abdominis musculocutaneous (TRAM) flap in 21 patients treated for stage III breast cancer.

METHODS

Data have been collected retrospectively on 21 patients diagnosed with stage III breast cancer between 1987 and 1994. All patients had mastectomy and immediate TRAM reconstruction. Thirteen patients received primary systemic therapy, 10 patients received postoperative consolidation radiotherapy to the operative site, and 3 patients received preoperative radiation.

RESULTS

Mean follow-up for the group was 26 months. Two patients died with disseminated disease: neither of them developed local disease recurrence in the operative site; 82% of the patients followed for at least two years are free of disease. Sixty-two percent of the patients received preoperative chemotherapy, the remaining patients received postoperative multiagent chemotherapy and/or radiation therapy. Two of the patients received autologous bone marrow transplants after their adjuvant therapy. Ten patients had postoperative radiotherapy for consolidation; three patients received preoperative radiation.

CONCLUSIONS

Immediate TRAM reconstruction for stage III breast cancer is not associated with a delay in adjuvant therapy or an increased risk of local relapse. It facilitates wide resection of involved skin without skin grafting. Radiation therapy can be delivered to the reconstructed breast when indicated without difficulty. Breast reconstruction facilitates surgical resection of stage III breast cancer with primary closure and should be considered if the patient desires immediate breast reconstruction.

Characterization of a chromosome-specific chimpanzee alpha satellite subset: evolutionary relationship to subsets on human chromosomes

Alpha satellite DNA is a tandemly repeated DNA family found at the centromeres of all primate chromosomes examined. The fundamental repeat units of alpha satellite DNA are diverged 169- and 172-bp monomers, often found to be organized in chromosome-specific higher-order repeat units. The chromosomes of human (Homo sapiens (HSA)), chimpanzee (Pan troglodytes (PTR) and Pan paniscus), and gorilla (Gorilla gorilla) share a remarkable similarity and synteny. It is of interest to ask if alpha satellite arrays at centromeres of homologous chromosomes between these species are closely related (evolving in an orthologous manner) or if the evolutionary processes that homogenize and spread these arrays within and between chromosomes result in nonorthologous evolution of arrays. By using PCR primers specific for human chromosome 17-specific alpha satellite DNA, we have amplified, cloned, and characterized a chromosome-specific subset from the PTR chimpanzee genome. Hybridization both on Southern blots and in situ as well as sequence analysis show that this subset is most closely related, as expected, to sequences on HSA 17. However, in situ hybridization reveals that this subset is not found on the homologous chromosome in chimpanzee (PTR 19), but instead on PTR 12, which is homologous to HSA 2p.

Rapid bright-field detection of oligonucleotide primed in situ (PRINS)-labeled DNA in chromosome preparations and frozen tissue sections

We describe a new application of a bright-field microscopic procedure for rapid enzyme cytochemical detection of repeated DNA sequences in metaphase preparations and frozen tissue sections. Various chromosome-specific oligonucleotide primers were used in up to three sequential primed in situ (PRINS) labeling reactions together with Taq DNA polymerase and biotin, digoxigenin and/or fluorescein isothiocyanate (FITC)-modified nucleotides. DNA target sequences were localized simultaneously by the precipitates of the horseradish peroxidase-diaminobenzidine (PO-DAB, brown color), alkaline phosphatase-Fast Red (APase-Fast Red, red color) and horseradish peroxidase-teramethylbenzidine (PO-TMB, green color) reaction in hematoxylin counterstained metaphases and interphase nuclei using a standard bright-field microscope. In addition, a protocol is reported for the application of PRINS to frozen tissue sections from normal colon and bladder epithelium. Methanol/acetic acid fixation in combination with a pepsin digestion before performing the PRINS reaction proved to be critical steps in the total procedure that permits access of the PRINS reactants, while preserving the morphology of the nuclei in the tissue. Quantification of PRINS signals showed the majority of epithelial cells with the expected two chromosome copies. The described procedures can be considered valuable tools for application in molecular cytogenetics, cell biology and pathology.

Human repeat-mediated integration of selectable markers into somatic cell hybrids

We describe a strategy to introduce preferentially the dominant selectable marker neoR into the human chromosome within a monochromosome hybrid cell line. Integration of a construct containing the marker is mediated by human-specific repeat elements that promote multilocus human-specific integration with a single targeting vector. We tested two classes of repeat elements: the Alu family of SINE repeats and the Line1 repeat family. We show that Alu sequences alone are insufficient to direct human-specific integration but when used in combination with a Line1 element, or when only Line1 elements are included, integration of the vector into the human component of a monochromosome somatic cell hybrid is favored. The vectors also carry sequences that facilitate mapping and selective cloning of the targeted region. This strategy provides a means to generate selectable human subchromosomal fragments that can be used for localization of genes through positional cloning and, more important, for the identification of functional units through DNA transfer.

Power spectrum of the fast Fourier transform for measurement of standing balance

Power spectrum of the force moment generated from the fast Fourier transform (FFT) was utilised to evaluate standing balance on a force platform. The principles on generating and analysing an FFT spectrum from the output of the force platform are illustrated. Test-retest reliability of twelve healthy young people (age = 26 +/- 4 years) was performed with the preferred leg stance. The intraclass correlation coefficient (ICC), R, of mean power (P), spectral area (Sx) and maximum power (Px) were 0.89, 0.85 and 0.89 respectively, indicating that the spectral parameters are reliable quantitative measures of balance. Pearson product moment (PPM), r, of these spectral parameters were 0.95, 0.85 and 0.95 respectively showing that these spectral parameters are significantly correlated (p < 0.01). A comparison was made with respect to the one legged stance and two legged stance steadiness. The one legged stance (Sx = 95.75 cm.Hz) was significantly less stable than the two legged stance (Sx = 41.58 cm.Hz) with a value of 9.37. Moreover, the one legged stance was highly correlated to the two legged stance (r = 0.84), indicating that, in general, a subject who has a stable one legged stance should have a stable two legged stance.