The effects of natural and anthropogenic environmental changes on ecosystem processes at the catchment scale.

The catchment is the smallest natural unit of the landscape that combines linked terrestrial and aquatic ecosystems. The fluxes of water and elements through the catchment link the various components of the system; biotic and abiotic, terrestrial and aquatic, plants and soils, atmosphere and vegetation, soils and waters. A large amount of empirical evidence now demonstrates that the impacts of natural and anthropogenic changes on the various components of catchment ecosystems are tightly connected.

How to make professional practice models work.

Professional practice models and shared governance have had much attention recently. They have been credited with being the answer to nurse retention, advancing the nursing profession, expanding nursing roles, and increasing autonomy for practice and work life. This article describes strategies for implementing and maintaining a professional practice model.

Mucormycosis in a patient with sarcoidosis.

Mucormycosis is a rare complication of sarcoidosis. We report only the third instance of mucormycosis occurring in a patient with sarcoidosis. Corticosteroid therapy, even short courses of less than one month duration, appears to be a major risk factor for the development of mucormycosis.

BDNF enhances the differentiation but not the survival of CNS stem cell-derived neuronal precursors.

We have previously reported the isolation of an EGF-responsive precursor from the embryonic and adult mouse striatum. This precursor exhibits self renewal and the ability to produce a sphere of undifferentiated cells which can be induced to differentiate into neurons and glia. RT-PCR analysis of these spheres of undifferentiated cells revealed the expression of mRNA for the trkB neurotrophin receptor, both with and without the catalytic domain, and little or no expression of trkA or trkC.

Information architects: data by design.

HMOs and other network-based health plans are harnessing the power of information--building integrated data infrastructures to meet the needs of members, caregivers, and employers.

Human class II major histocompatibility complex gene transfer into murine neuroblastoma leads to loss of tumorigenicity, immunity against subsequent tumor challenge, and elimination of microscopic preestablished tumors.

Immunological recognition of transformed cells is critically important to limit tumor development and proliferation. Because established tumors have escaped immune recognition and elimination, novel strategies to enhance antitumor immunity have been developed. A unique approach has used the introduction of genes encoding major histocompatibility complex (MHC) antigens into tumor cells.

The T alpha 1 alpha-tubulin promoter specifies gene expression as a function of neuronal growth and regeneration in transgenic mice.

We have previously demonstrated that one member of the alpha-tubulin multigene family, termed T alpha 1 in rats, is regulated as a function of neuronal growth and regeneration. To elucidate the molecular mechanisms responsible for coupling gene expression to morphological differentiation, we have isolated the T alpha 1 gene, have fused 1.1 kb of the 5' flanking region to a nuclear lacZ reporter gene, and have generated transgenic mice.

Neural stem cells in the adult mammalian forebrain: a relatively quiescent subpopulation of subependymal cells.

Dissection of the subependyma from the lateral ventricle of the adult mouse forebrain is necessary and sufficient for the in vitro formation of clonally derived spheres of cells that exhibit stem cell properties such as self-maintenance and the generation of a large number of progeny comprising the major cell types found in the central nervous system. Killing the constitutively proliferating cells of the subependyma in vivo has no effect on the number of stem cells isolated in vitro and induces a complete repopulation of the subependyma in vivo by relatively quiescent stem cells found within the subependyma. Depleting the relatively quiescent cell population within the subependyma in vivo results in a corresponding decrease in spheres formed in vitro and in the final number of constitutively proliferating cells in vivo, suggesting that a relatively quiescent subependymal cell is the in vivo source of neural stem cells.

A critique: Watson's caring ideology. The proper focus of psychiatric nursing?

1. Watson's (1989) conceptualization of care possesses limited clinical utility in psychosocial contexts, given that there already exists an extensive lineage of human concepts of helping, within various psychotherapeutic traditions. 2.

Topoisomerase II mediated DNA lesions induced by acridine-4-carboxamide and 2-(4-pyridyl)quinoline-8-carboxamide.

Acridine-4-carboxamide and 2-(4-pyridyl)quinoline-8-carboxamide represent a new generation of antitumor intercalators related to amsacrine (m-AMSA), a classic topoisomerase II-targeted drug. We examined the ability of these tricyclic carboxamides to induce DNA lesions that reflect the stabilization of topoisomerase II cleavage complexes. DNA-protein cross-links (DPC) and DNA double-strand breaks (DSB) were assessed in mouse fibrosarcoma cells (line 935.

Spatial patterns concentrations in upland Wales in relation to catchment forest cover and forest age.

Data on nitrate nitrogen were collected weekly during 1984 from 136 sites on streams in upland Wales. Mean nitrate concentrations in summer (0.02 to 1.

The influence of clients' perceptions of the helping relationship in the development of an empathy scale.

The paper includes a discussion about the origins of items on a measure of cognitive-behavioural empathy. This scale was originally produced by the author as a teaching tool for an empathy education programme (for RNs) and subsequently developed into a quantitative measure of empathy. The instrument is being used as part of a triangulated approach for data collection on research into the effectiveness of an educational programme about registered nurses' empathy.

Central nervous system growth and differentiation factors: clinical horizons--truth or dare?

Growth factors are potent and effective regulators of nerve-cell differentiation and survival. In the past year, several compelling studies have suggested that two proteins, glial derived neurotrophic factor and ciliary neurotrophic factor, may be useful in clinical approaches to treating injury or diseases of the nervous system. In addition, delivery of such factors to the central nervous system may be facilitated by a number of recently reported technologies: growth factor-antibody conjugates, polymer encapsulation and adenovirus vectors.

bFGF regulates the proliferative fate of unipotent (neuronal) and bipotent (neuronal/astroglial) EGF-generated CNS progenitor cells.

In cultures of embryonic and adult mouse striatum, we previously demonstrated that EGF induces the proliferation of putative stem cells, which give rise to spheres of undifferentiated cells that can generate neurons and astrocytes. We report here that the spheres of undifferentiated cells contain mRNA and protein for the FGF receptor (FGFR1). Indirect immunocytochemistry demonstrated that many of the cells within the EGF-generated spheres were immunoreactive for FGFR1.

Dose-dependent antagonism and potentiation of nitrous oxide antinociception by naloxone in mice.

Administration of the anesthetic gas nitrous oxide (N2O) evoked a concentration-dependent antinociceptive effect in mice as assessed by the abdominal constriction test. Depending on the dose and route of pretreatment with the opioid receptor blocker naloxone, the N2O drug effect was either antagonized or potentiated. After s.

A preliminary study of the relationship between central auditory processing disorder and attention deficit disorder.

Fifteen boys aged six to ten who met the criteria for attention deficit disorder (ADD) were compared with ten boys who did not have ADD in a double-blind, placebo-controlled, single-crossover study of methylphenidate. To assess the degree of overlap between ADD and central auditory processing disorder (CAPD), all subjects were assessed on parent and teacher behavior rating scales, as well as a battery of CAPD tests at baseline and after three and six weeks of treatment. Twelve of the 15 subjects with ADD and none of the subjects without ADD met the criteria for CAPD.

Determination of 5,10,15,20-tetra-(m-hydroxyphenyl)chlorin in tissues by high performance liquid chromatography.

A procedure for the extraction and high performance liquid chromatographic (HPLC) determination of the photodynamic therapeutic agent 5,10,15,20-tetra(m-hydroxyphenyl)chlorin in human, rat and mouse tissues following intravenous administration of the drug is described. The tissue (tumour, skin, muscle and liver) was homogenized and extracted into a mixture of methanol:dimethyl sulphoxide:water (32:8:1 by vol.) containing, 5,10,15,20-tetra(p-hydroxyphenyl)chlorin as the internal standard.

A case of deletion 14(q22.1-->q22.3) associated with anophthalmia and pituitary abnormalities.

An interstitial deletion of the region q22.1-->q22.3 of chromosome 14 is described in a child with bilateral anophthalmia, dysmorphic features including micrognathia, small tongue, and high arched palate, developmental and growth retardation, undescended testes with a micropenis, and hypothyroidism.

Influence of soil hydrological pathways on stream aluminium chemistry at Llyn Brianne, mid-wales.

Storm runoff in afforested catchments at Llyn Brianne is acidic and Al-bearing. At baseflows, stream water is well-buffered with low Al levels. This paper presents the results of a study into how hydrological pathways account for these variations in stream-water chemistry.

Determination of 5,10,15,20-tetra-(m-hydroxyphenyl)chlorin in human plasma by high performance liquid chromatography.

A high performance liquid chromatographic method for the determination of the photodynamic chemotherapeutic agent 5,10,15,20-tetra(m-hydroxyphenyl)chlorin (m-THPC) in human plasma following intravenous infusion is described. The procedure involves extraction of the drug in plasma with methanol/dimethyl sulphoxide (4:1 v/v) containing 5,10,15,20-tetra(p-hydroxyphenyl)chlorin as the internal standard and separation on a C18 reversed phase column with acetonitrile:0.1% trifluoroacetic acid (77:23 v/v) as the mobile phase.

The ethics of cardiopulmonary resuscitation. II. Medical logistics and the potential for good response.

Mismatches between provision of paediatric cardiopulmonary resuscitation (CPR) and potential to benefit are examined. Deficiencies are most likely to occur in peripheral maternity units but futile CPR is more common in emergency departments where the child is unknown. Decision making in individual cases is best retained by the medical profession for the sake of the child and family.

The ethics of cardiopulmonary resuscitation. I. Background to decision making.

Futile cardiopulmonary resuscitation (CPR) may prevent humane care of the dying child and deprive parents of the opportunity to express their love, grief, and dedication at a critical moment, while appropriate and successful CPR may restore intact their child. Attempted resuscitation of corpses or children with terminal illness indicates inadequate knowledge, discrimination, and decision making. CPR is a medical procedure applicable to certain medical problems; weighing up the risks and benefits in each individual case is a medical function that is constrained by the law and must take full note of patient and family preferences, but cannot be governed by them and should not be over-ruled by laws based on complex but different cases.

A multipotent EGF-responsive striatal embryonic progenitor cell produces neurons and astrocytes.

The mitogenic actions of epidermal growth factor (EGF) were examined in low-density, dissociated cultures of embryonic day 14 mouse striatal primordia, under serum-free defined conditions. EGF induced the proliferation of single progenitor cells that began to divide between 5 and 7 d in vitro, and after 13 d in vitro had formed a cluster of undifferentiated cells that expressed nestin, an intermediate filament present in neuroepithelial stem cells. In the continued presence of EGF, cells migrated from the proliferating core and differentiated into neurons and astrocytes.