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L Campbell

Publications and source records attributed to L Campbell.

At least 109 records · Page 6Linked to original sources
PubMed1994

Reunions between adoptees and birth parents: the adoptive parents' view.

This article looks at the reactions of adoptive parents to reunions between their adopted children and the children's birth parents. The focus is on how adoptive parents feel the reunion affects the family's integrity. Three types of family responses are identified: (1) closed, (2) divided, and (3) open. Acceptance of the differences between families created by adoption of children and those created by childbirth was a factor in the families' openness. Closed families saw no difference, and reunion suggested to the adults that they had failed as parents. Parents in open families understood the difference in families, saw the children as separate, and felt no threat to their competence as parents. Families' need for boundaries is examined, and the way the concept of family is constructed is discussed. Implications for the practice of adoption are considered.

Adolescent↗
PubMed1994

Uncoupling of bacterioplankton and phytoplankton production in fresh waters is affected by inorganic nutrient limitation.

Pelagic bacterial production is often positively correlated, or coupled, with primary production through utilization of autotrophically produced dissolved organic carbon. Recent studies indicate that inorganic N or P can directly limit both bacterial and phytoplanktonic growth. Our mesocosm experiments, with whole communities from mesotrophic Calder Lake, test whether this apparent bacterial-algal coupling may be the result of independent responses to limiting inorganic nutrients. In systems without N additions, numbers of bacteria but not phytoplankton increased 2- to 2.5-fold in response to P fertilization (0 to 2.0 mumol of P per liter); this resulted in uncoupled production patterns. In systems supplemented with 10 mumol of NH(4)NO(3) per liter, P addition resulted in up to threefold increases in bacteria and two- to fivefold increases in total phytoplankton biomass (close coupling). P limitation of pelagic bacteria occurred independently of phytoplankton dynamics, and regressions between bacterial abundance and phytoplankton chlorophyll a were nonsignificant in all systems without added N. We describe a useful and simple coupling index which predicts that shifts in phytoplankton and bacterioplankton growth will be unrelated (Delta bacteria/Delta phytoplankton --> either + infinity or - infinity) in systems with inorganic N/P (molar) ratios of < approximately 40. In systems with higher N/P ratios (>40), the coupling index will approach 1.0 and close coupling between bacteria and phytoplankton is predicted to occur.

Journal Article↗
PubMed1994

Cellular immunity to a determinant common to glutamate decarboxylase and coxsackie virus in insulin-dependent diabetes.

Insulin-dependent diabetes (IDD) results from the autoimmune destruction of the insulin-producing pancreatic beta cells. Autoreactive T-lymphocytes are thought to play a pivotal role in the pathogenesis of IDD; however, the target antigens of these cells, as well as the inductive events in the disease, are unclear. PBMC in persons with or at increased risk for IDD show elevated reactivity to the beta cell enzyme glutamate decarboxylase (GAD). To identify the T-lymphocyte-reactive determinants of GAD, an overlapping set of synthetic peptides was used to stimulate the PBMC from these individuals, PBMC responsiveness to GAD peptides was not restricted to those with IDD, and a number of peptides elicited responses in PBMC. However, the major determinant of GAD recognized by persons at increased risk for IDD was amino acids 247-279, a region which has significant sequence similarity to the P2-C protein of Coxsackie B virus (47% of 15 increased risk [islet cell autoantibody-positive relatives]; 25% of 16 newly diagnosed IDD patients; and 0% of 13 healthy control subjects). Responses to tetanus and insulin antigens were not different between the study groups. In addition, PBMC from individuals responding to GAD peptides within 247-279 also responded to a Coxsackie viral peptide (i.e., P2-C amino acids 32-47), an observation supporting potential molecular mimicry in this immune response. Although the role of environmental agents in the pathogenesis of the disease remains unclear, these cellular immunological findings support the epidemiological evidence suggesting an inductive role for enteroviruses like Coxsackie B in the autoimmunity underlying IDD.

Adolescent↗
PubMed1994

A 57-year-old man with bruising and joint pain.

The differential diagnosis for a 57-year-old man with joint pain, bruising, and diarrhea is discussed in the setting of a Clinical Pathological Conference at Louisiana State University Medical Center in Shreveport, La. The pathophysiology and etiology of malabsorptive states are presented.

Diagnosis, Differential↗
PubMed1994

Complex repetitive arrangements of gene sequence in the candidate region of the spinal muscular atrophy gene in 5q13.

Childhood-onset proximal spinal muscular atrophy (SMA) is a heritable neurological disorder, which has been mapped by genetic linkage analysis to chromosome 5q13, in the interval between markers D5S435 and D5S557. Here, we present gene sequences that have been isolated from this interval, several of which show sequence homologies to exons of beta-glucuronidase. These gene sequences are repeated several times across the candidate region and are also present on chromosome 5p. The arrangement of these repetitive gene motifs is polymorphic between individuals. The high degree of variability observed may have some influence on the expression of the genes in the region. Since SMA is not inherited as a classical autosomal recessive disease, novel genomic rearrangements arising from aberrant recombination events between the complex repeats may be associated with the phenotype observed.

Amino Acid Sequence↗
PubMed1993

Lack of immune responsiveness to bovine serum albumin in insulin-dependent diabetes.

BACKGROUND: Epidemiologic studies have implicated the ingestion of cow's milk in the pathogenesis of insulin-dependent diabetes mellitus (IDDM). Moreover, in a recent study, 100 percent of patients with new-onset IDDM had antibodies against bovine serum albumin (BSA), with a majority directed against a 17-amino-acid BSA peptide (ABBOS). Cellular immune mechanisms are thought to be the principal mediators of pancreatic beta-cell destruction in IDDM. METHODS: We measured the responses of peripheral-blood mononuclear cells to BSA and ABBOS or serum IgG anti-BSA antibodies (by particle-concentration fluorescence immunoassay) in 71 patients with IDDM, 55 subjects at various degrees of risk for IDDM, 36 patients with other autoimmune disorders (chronic autoimmune thyroiditis, rheumatoid arthritis, and systemic lupus erythematosus), and 48 normal subjects. RESULTS: The responses of peripheral-blood mononuclear cells to BSA or ABBOS were positive in 2 of 24 patients with new-onset IDDM, 1 of 25 first-degree relatives of patients with IDDM who were negative for islet-cell antibodies, 2 of 30 first-degree relatives of patients with IDDM who were positive for islet-cell antibodies, 1 of 28 patients with established IDDM, and 1 of 29 normal subjects. Similarly, anti-BSA antibodies were not detected significantly more often in patients with new-onset IDDM (3 of 31, 10 percent) than in normal subjects (1 of 37, 3 percent; P = 0.32). However, many patients with autoimmune disease and subjects at increased risk for IDDM had anti-BSA antibodies (frequency, 10 to 31 percent). CONCLUSIONS: Anti-BSA antibodies may reflect a general defect in the process of immunologic tolerance associated with a predisposition to autoimmunity rather than immunity specific to beta cells. The absence of cellular immunity to BSA and ABBOS in IDDM does not support a role for this antigen in the pathogenesis of the disorder.

Adult↗
PubMed1993

Trinucleotide repeat amplification and hypermethylation of a CpG island in FRAXE mental retardation.

We have cloned the fragile site FRAXE and demonstrate that individuals with this fragile site possess amplifications of a GCC repeat adjacent to a CpG island in Xq28 of the human X chromosome. Normal individuals have 6-25 copies of the GCC repeat, whereas mentally retarded, FRAXE-positive individuals have > 200 copies and also have methylation at the CpG island. This situation is similar to that seen at the FRAXA locus and is another example in which a trinucleotide repeat expansion is associated with a human genetic disorder. In contrast with the fragile X syndrome, the GCC repeat can expand or contract and is equally unstable when passed through the male or female line. These results also have implications for the understanding of chromosome fragility.

Base Sequence↗
PubMed1993

Judgments of moving and intending to move in a timed-response task.

Subjects performed a timed-response task in which they attempted to synchronize a rapid flexion of the index finger of their preferred hand with the last of a train of four regularly spaced acoustic clicks. The task was used to stabilize the execution time of a simple voluntary response in order to facilitate psychophysical judgments about the subjects' perception of having responded and of having intended to respond. In the first experiment, male subjects (N = 6) adjusted the appearance time of a reference stimulus (a brief percutaneous pulse to the responding finger) until it appeared to be simultaneous with their perception of having made the response. All subjects adjusted the reference stimulus to appear after response onset during the latter half of the force impulse. This finding suggests that the perception of having responded is based on peripheral feedback from the response. In the second experiment, male subjects (N = 6) performed the same motor task, but adjusted the time of the reference stimulus so that it appeared to be simultaneous with their intention to respond. Two subjects were not able to do the task successfully; the remaining four subjects adjusted the reference stimulus to appear from 101 to 145 ms before response onset. This finding suggests that the intention to respond is perceptually separable from the response itself and occurs at a measurable time before response onset.

Adult↗
PubMed1993

The utrophin and dystrophin genes share similarities in genomic structure.

Utrophin and dystrophin are highly homologous proteins which are reciprocally expressed in DMD (Duchenne muscular dystrophy) muscle. The remarkable similarity of these proteins suggests that they may play a similar cellular role in some circumstances; if this were the case then utrophin may be capable of replacing dystrophin in DMD patients. In this paper we show that the genomic structure of the utrophin gene is similar to the dystrophin gene, further exemplifying the relatedness of the two genes and their gene products. We have constructed a 1.25 Mb contig of eight yeast artificial chromosome (YAC) clones covering the utrophin gene located on chromosome 6q24. Utrophin is encoded by multiple small exons spanning approximately 900 kb. The distribution of exons within the genomic DNA has similarities to that of the dystrophin gene. In contrast to dystrophin, the utrophin gene has a long 5' untranslated region composed of two exons and a cluster of unmethylated, rare-cutting restriction enzyme sites at the 5' end of the gene. Similarities between the genomic structure suggest that utrophin and dystrophin arose through an ancient duplication event involving a large region of genomic DNA.

Base Sequence↗
PubMed1993

A contig of non-chimaeric YACs containing the spinal muscular atrophy gene in 5q13.

We have constructed a contig of non-chimaeric yeast artificial chromosomes (YACs) across the candidate region for childhood autosomal recessive spinal muscular atrophy (SMA) in 5q13. A novel microsatellite reduces the candidate region to approximately 400kb of DNA distal to D5S435. The candidate region contains blocks of chromosome 5 specific repeats which have copies on 5p as well as elsewhere on 5q. Restriction mapping of the YACs reveals at least one CpG island in the SMA gene region. The YAC maps indicate that the contig contains minimal rearrangements or deletions. The data show the value of screening several YAC libraries simultaneously in order to construct a set of overlapping sequences suitable for candidate gene searches and direct genomic sequencing.

Base Sequence↗
PubMed1993

Nursing salaries and practice patterns: a nationwide evaluation by the Oncology Nursing Society.

This article summarizes the results of a national survey of salary, staffing, and professional practice patterns in oncology nursing conducted by the Oncology Nursing Society. The respondents represent a wide geographic distribution, and data were analyzed in the aggregate, as well as by American Hospital Association (AHA) regions, to allow for predictions of regional as well as national trends. This article reports on national and regional trends in salaries for entry-level and experienced practitioners; salary patterns for agency and float pool nurses; and the methods for awarding salary increases to nursing personnel in the past year. National trends in a variety of personnel practices affecting oncology nursing (e.g., shifts, self-scheduling, tuition reimbursement, and certification) are also presented. The data in this study come from a broad-based and geographically well-distributed sample that allows for meaningful national comparisons.

Economics, Nursing↗
PubMed1993

The ethics of caring.

It is critical that those of us in leadership roles strive to match the level of caring exhibited by our clinicians. Over the long term the capacity to which we demonstrate a similar level of ethics in caring may determine the success or failure of our individual agencies and the ultimate success of the home care industry.

Aged↗
PubMed1993

Amber: all change.

Explore the source record for details and available documents.

Adaptation, Psychological↗
PubMed1992

Response of peripheral-blood mononuclear cells to glutamate decarboxylase in insulin-dependent diabetes.

Insulin-dependent diabetes is characterised by autoantibodies to several pancreatic-islet-cell antigens, including glutamate decarboxylase. We measured the proliferative responses to this antigen of peripheral-blood mononuclear cells from patients with newly diagnosed insulin-dependent diabetes, relatives of diabetic patients, and healthy controls. The likelihood of a positive response was substantially greater among the diabetic patients and relatives positive for islet-cell autoantibodies (ICA) than among subjects at low risk of diabetes (controls and ICA-negative relatives). Glutamate decarboxylase may have a pathogenetic role in insulin-dependent diabetes.

Autoantibodies↗
PubMed1992

Prenatal diagnosis and investigation of a fetus with chondrodysplasia punctata, ichthyosis, and Kallmann syndrome due to an Xp deletion.

We report the prenatal diagnosis of a male fetus with X-linked recessive chondrodysplasia punctata (CDPX), steroid sulphatase (STS) deficiency, X-linked Kallmann syndrome (KAL), and a chromosome deletion at Xp22.31. Biochemical analysis of bone from this case indicates that CDPX is not a defect of vitamin K metabolism. Immunocytochemical study of the brain suggests that KAL is a defect in neuronal migration.

Adult↗
PubMed1992

Memory accessibility and probability judgments: an experimental evaluation of the availability heuristic.

Consistent with Tversky and Kahneman's (1973, 1974) availability heuristic hypothesis, the current study found a negative correlation between recall latency for past events and the perceived future probability of similar events. Furthermore, when the relative accessibility of memories of positive and negative events was experimentally manipulated using the Velten mood-induction procedure, the perceived future probabilities of similar events also changed in a manner consistent with the availability heuristic account. Reductions in recall latencies resulting from the mood manipulations were, as predicted, related to increases in perceived probability, and vice versa. Partial correlations indicated that this association between the observed patterns of changes in recall latencies and probability judgments could not be accounted for by the existence of independent associations between each of these effects and the magnitude of mood change.

Adolescent↗