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R L Anderson

Publications and source records attributed to R L Anderson.

At least 37 records · Page 2Linked to original sources
PubMed2001

Development of electrophysiological and morphological diversity in autonomic neurons.

The generation of neuronal diversity requires the coordinated development of differential patterns of ion channel expression along with characteristic differences in dendritic geometry, but the relations between these phenotypic features are not well known. We have used a combination of intracellular recordings, morphological analysis of dye-filled neurons, and stereological analysis of immunohistochemically labeled sections to investigate the development of characteristic electrical and morphological properties of functionally distinct populations of sympathetic neurons that project from the celiac ganglion to the splanchnic vasculature or the gastrointestinal tract of guinea pigs. At early fetal stages, neurons were significantly more depolarized at rest compared with neurons at later stages, and they generally fired only a single action potential. By mid fetal stages, rapidly and slowly adapting neurons could be distinguished with a topographic distribution matching that found in adult ganglia. Most rapidly adapting neurons (phasic neurons) at this age had a long afterhyperpolarization (LAH) characteristic of mature vasomotor neurons and were preferentially located in the lateral poles of the ganglion, where most neurons contained neuropeptide Y. Most early and mid fetal neurons showed a weak M current, which was later expressed only by rapidly-adapting and LAH neurons. Two different A currents were present in a subset of early fetal neurons and may indicate neurons destined to develop a slowly adapting phenotype (tonic neurons). The size of neuronal cell bodies increased at a similar rate throughout development regardless of their electrical or neurochemical phenotype or their topographical location. In contrast, the rate of dendritic growth of neurons in medial regions of the ganglion was significantly higher than that of neurons in lateral regions. The apparent cell capacitance was highly correlated with the surface area of the soma but not the dendritic tree of the developing neurons. These results demonstrate that the well-defined functional populations of neurons in the celiac ganglion develop their characteristic electrophysiological and morphological properties during early fetal stages of development. This is after the neuronal populations can be recognized by their neurochemical and topographical characteristics but long before the neurons have finished growing. Our data provide strong circumstantial evidence that the development of the full phenotype of different functional classes of autonomic final motor neurons is a multi-step process likely to involve a regulated sequence of trophic interactions.

Action Potentials↗
PubMed2001

Role of priming stresses and Hsp70 in protection from ischemia-reperfusion injury in cardiac and skeletal muscle.

Ischemia-reperfusion injury limits the survival of muscle involved in tissue trauma or transfers during microsurgical reconstruction. Priming stresses such as ischemic preconditioning or mild hyperthermia have frequently been associated with improved survival of ischemic-reperfused cardiac muscle, such protection coinciding with induction of the stress-related heat shock protein 70 (Hsp70). Little is known about the response of skeletal muscle to priming stresses. This review summarizes the current knowledge on the use of priming stresses as protective strategies against the consequences of ischemia-reperfusion in cardiac and skeletal muscle and the potential role of Hsp70.

Animals↗
PubMed2000

Quality of life of persons with severe mental illness living in an intermediate care facility.

This study examined resident characteristics, clinical factors, and mental health service utilization associated with quality of life (QOL) for residents living in an Intermediate Care Facility (ICF). This study also utilized published literature to compare the QOL of ICF residents to persons with psychiatric disorders living in other residential settings. Chart review and interviews were used to study 100 randomly selected residents living in an ICF with a chart diagnosis of schizophrenia. Multivariate analyses suggest that higher levels of QOL are associated with reports that psychological problems did not interfere with work and activities and with lower levels of being a danger to others. Also, a comparison of the QOL scores reported by ICF residents to other published mentally ill populations suggests that residents of the ICF report somewhat higher QOL scores than state hospital patients, but lower scores as compared to other community samples. Data provide insight into the types of problems faced by residents of an intermediate care facility. These findings have implications for understanding the importance of mental health service utilization on QOL.

Adult↗
PubMed2000

Prior heat stress improves survival of ischemic-reperfused skeletal muscle in vivo.

The ability of heat stress to improve the survival of ischemic-reperfused skeletal muscle in vivo was investigated. Ischemia-reperfusion was applied using the rat hindlimb tourniquet model. The viability of ischemic-reperfused muscle (11 +/- 1%) was increased by prior mild heat stress (86 +/- 2%). To investigate whether heat shock protein 70 (Hsp 70) expression in the muscle of the heated limb was responsible for this protection, the survival of Hsp 70-expressing transduced myoblasts and myocytes was measured after exposure to mediators of ischemia-reperfusion injury. Survival was improved in Hsp 70-positive myoblasts but not in myocytes, suggesting that the mechanism of protection conferred by heat stress in vivo cannot be explained by the expression of Hsp 70 in myocytes and may involve a more complex mechanism. In conclusion, prior heat stress is effective in protecting mature skeletal muscle in vivo against necrosis after ischemia-reperfusion and has potential for use in microsurgical procedures requiring tourniquet applications.

Animals↗
PubMed2000

MMP-9 secretion and MMP-2 activation distinguish invasive and metastatic sublines of a mouse mammary carcinoma system showing epithelial-mesenchymal transition traits.

We have investigated the gelatinase profiles and invasiveness of clonal tumour sublines derived from a spontaneously arising mammary tumour in a Balb/cfC3H mouse. The 67NR. 66c14 and 4T1.2 sublines have low, intermediate and high metastatic potential respectively. In Boyden chamber studies, Matrigel invasion was seen to be progressively higher in the more metastatic lines 4T1.2>66c14>67NR, consistent with MMP-2 activation potential, MMP-9 secretion, and migration over either type I or IV collagen, which were low in both 67NR and 66c14 cells compared to 4T1.2 cells. These attributes are consistent with those seen in human breast cancer cell lines which appear to have undergone an epithelial-mesenchymal transition (EMT) as indicated by vimentin expression. We were, however, surprised to find vimentin expression, MT1-MMP expression and stellate Matrigel outgrowth in the non-invasive, non-metastatic 67NR cells. indicating that they had undergone an EMT despite not being invasive. We conclude that the EMT is manifested to differing degrees in these three clonal cell lines, and that the 67NR cells have either undergone a partial EMT or have since lost certain important attributes of the EMT-derived phenotype. This model should prove useful in further characterizing the regulation of MTI-MMP mediated MMP-2 activation and delineating the EMT in breast cancer progression.

Animals↗
PubMed2000

Burn scar malignancies of the eyelids.

PURPOSE: To study the clinicopathologic characteristics and treatment of eyelid carcinomas developing in thermal burn scars. METHODS: A review of eight cases of eyelid burn scar malignancies: two from our own experience and six from published reports. RESULTS: Reported cases of burn scar malignancy of the eyelid are short-latency basal cell carcinomas. All carcinomas arose from small superficial burns. These potentially aggressive tumors respond well to local excision. CONCLUSION: As with other areas of the body, eyelid burn scars may undergo neoplastic degeneration. These carcinomas are predominately short latency basal cell carcinomas, rather than long-latency squamous cell carcinomas that are more common elsewhere in the body, including the head and neck region. Clinicians should be diligent in the long-term surveillance of all eyelid burns.

Adult↗
PubMed2000

Heat-induced alterations in the localization of HSP72 and HSP73 as measured by indirect immunohistochemistry and immunogold electron microscopy.

The heat shock proteins are a family of stress-inducible proteins that act as molecular chaperones for nascent proteins and assist in protection and repair of proteins whose conformation is altered by stress. HSP72 and HSP73 are two major cytosolic/nuclear stress proteins of mammalian cells, with extensive sequence homology. HSP73 is constitutively expressed, whereas HSP72 is highly stress-inducible. However, it is unclear why two isoforms are expressed and whether these two proteins have different functions in the cell. To assist in the delineation of function, we have completed a detailed study of the localization of HSP72 and HSP73 in the cell before and after heat stress, using two different methods of detection. By indirect immunohistochemistry, the localization of these two proteins is similar, cytoplasmic and nuclear in nonstressed cells with a translocation to nucleoli immediately after heat. By the more sensitive immunogold electron microscopy technique, differences in localization were noted. In nonstressed cells, HSP72 was primarily nuclear, localized in heterochromatic regions and in nucleoli. HSP73 was distributed throughout the cell, with most cytoplasmic label associated with mitochondria. Mitotic chromosomes were also heavily labeled. After stress, HSP72 concentrated in nuclei and nucleoli and HSP73 localized to nuclei, nucleoli, and cytoplasm, with increased label over mitochondria. These differences in localization suggest that the HSP72 and HSP73 may associate with different proteins or complexes and hence have different but overlapping functions in the cell.

Animals↗
PubMed2000

A family study of outpatients with borderline personality disorder and no history of mood disorder.

While several studies have examined psychiatric disorders in the relatives of individuals with borderline personality disorder, many of these studies have not employed a family study methodology and suffer from other methodological shortcomings. Thus, the conclusions from family data addressing the validity of borderline personality disorder, its relation to other conditions, and its distinction from mood disorders, continue to be debated. The present investigation employed a family study design with direct interviews with relatives, structured diagnostic interviews with both probands and relatives, and blind assessment of relatives. Rates of psychiatric disorders were examined in 563 relatives of outpatients with mood disorders (n = 119), 54 relatives of outpatients with borderline personality disorder and no history of mood disorder (n = 11), and 229 relatives of never psychiatrically ill controls (n = 45). Results indicate increased rates of mood disorders and personality disorders in the relatives of borderline probands compared with never psychiatrically ill controls. Familial aggregation of psychiatric disorders was generally similar for borderline personality and the mood disorder comparison group. The results suggest there may be common etiological factors between borderline personality disorder and mood disorders.

Adult↗
PubMed1999

Neurokinin-1 receptor localisation in guinea pig autonomic ganglia.

We have used multiple-labelling immunohistochemistry and confocal microscopy to determine the distribution of immunoreactivity to the tachykinin neurokinin-1 (NK(1)) receptors in guinea pig sympathetic ganglia. Although nerve fibres containing immunoreactivity to substance P were common in all ganglia except the superior cervical ganglia, most neurons expressing NK(1) receptor immunoreactivity were not closely surrounded by pericellular baskets of substance P-immunoreactive boutons. Conversely, many neurons surrounded by baskets of substance P-immunoreactive boutons lacked NK(1) immunoreactivity. In the coeliac and inferior mesenteric ganglia, NK(1) receptor expression was restricted almost entirely to noradrenergic neurons that contained somatostatin immunoreactivity and projected to the enteric plexuses. In the lumbar chain and paracervical ganglia, NK(1) immunoreactivity was expressed by nonnoradrenergic vasodilator neurons containing immunoreactivity to vasoactive intestinal peptide. Taken together, our results show that sympathetic neurons in different functional pathways express NK(1) receptor immunoreactivity. However, the neurons that could respond to endogenously released substance P through NK(1) receptors may be distant from presynaptic release sites. These observations suggest that, in sympathetic ganglia, substance P may modulate ganglionic transmission through heterosynaptic actions on NK(1) receptors.

Animals↗
PubMed1999

The survival of skeletal muscle myoblasts in vitro is sensitive to a donor of nitric oxide and superoxide, SIN-1, but not to nitric oxide or peroxynitrite alone.

The survival of skeletal muscle myoblasts in culture after exposure either to a donor of NO, sodium nitroprusside (SNP), or ethanamine, 2,2'-(hydroxynitrosohydrazono)bis-(DETA NONOate), or to a donor of both NO and O(-)(2), 3-morpholinosydnonimine hydrochloride (SIN-1), was investigated. SIN-1 reduced clonogenic survival markedly but donors of NO alone did not. The injurious effect of SIN-1 was prevented by oxyhemoglobin or by uric acid but not by superoxide dismutase. The exposure of myoblasts to authentic peroxynitrite (ONOO(-)) or to DETA NONOate in the presence of an O(-)(2)-generating system did not reduce their survival. The results show that NO or ONOO(-) alone is not detrimental to myoblast survival and suggest that SIN-1 toxicity is, at least in part, mediated by H(2)O(2) in this myoblast culture system.

Animals↗
PubMed1999

A novel orthotopic model of breast cancer metastasis to bone.

Breast cancer affects approximately one woman in twelve and kills more women than any other cancer. If detected early, patients have a five year survival rate of 66%, but once metastatic disease has developed, there is no effective treatment. About 70% of patients with metastatic disease have bone involvement, while lungs and liver are the other common targets. Bone metastases cause severe pain, pathological fractures and hypercalcaemia and thus are a significant clinical problem. The development of new therapies for metastatic breast carcinoma depends on a better understanding of the mechanism of homing of the tumour cells to bone, liver and lungs and the factors required for their growth in these organs. Research on mechanisms of breast cancer metastasis, particularly to bone, has relied on in vitro studies or on tumour models in which the inoculation route is designed to promote delivery of tumour cells to a specific organ. Metastases in bone are achieved by inoculation into the right ventricle of the heart. To our knowledge there has been no report of a model of metastatic spread from the mammary gland to distant sites which reliably includes bone. In this paper, we describe our recent development of a novel murine model of metastatic breast carcinoma. The new model is unique in that the pattern of metastatic spread closely resembles that observed in human breast cancer. In particular, these murine breast tumours metastasise to bone from the primary breast site and cause hypercalcaemia, characteristics not normally found in murine tumours, but common in human disease. Furthermore, in a preliminary characterisation of this model, we show that secretion of parathyroid hormone-related protein, a role for which has been implicated in breast cancer spread to bone, correlates with metastasis to bone. This model therefore provides an excellent experimental system in which to investigate the factors that control metastatic spread of breast cancer to specific sites, particularly bone. The special advantage of this system is that it involves the whole metastasis process, beginning from the primary site. Existing models consider mechanisms that pertain to growth of tumour once the site has been reached. An understanding of the regulation of these factors by potential therapeutic agents could lead to improvement in therapies designed to combat metastatic disease. For the first time, this development will allow exploration of the molecular basis of site-specific metastasis of breast cancer to bone in a clinically relevant model.

Animals↗
PubMed1999

Nodular fasciitis of the lower eyelid in a pediatric patient.

PURPOSE: To describe a 14-year-old boy with a 1-month history of a rapidly growing, nontender, lower eyelid mass. METHODS: The specimen was studied using light microscopy. RESULTS: Although magnetic resonance imaging suggested a chronic vascular lesion, histopathologic analysis after excisional biopsy was consistent with nodular fasciitis. CONCLUSIONS: Nodular fasciitis is a relatively common soft-tissue lesion and represents a benign, reactive process. Lesions in the head and neck develop more frequently in children and adolescents than in adults, but periorbital lesions are uncommon. This is the first reported case of nodular fasciitis of the lower eyelid in a pediatric patient.

Adolescent↗
PubMed1999

A novel mechanism for benign essential blepharospasm.

PURPOSE: The purpose of this study is to test the hypothesis that the photophobia of benign essential blepharospasm (BEB) is caused by sympathetically maintained pain. METHODS: Nineteen patients with photophobia and BEB were enrolled in an unblinded prospective treatment trial. The intervention was blockade of the superior sympathetic ganglion with local anesthetic. Outcome measures included the patient's subjective report of ocular surface dryness, foreign body sensation, and eyelid spasm. We also obtained video recordings of eyelid movements. RESULTS: Of the 19 patients, 13 reported subjective improvement in BEB symptoms after cervical sympathetic blockade (CSB). Thirteen of 19 patients also had objective evidence of decreased light-induced eyelid spasm after CSB. Ocular surface disease was present in 18 of 19 patients. CONCLUSION: These data support the hypothesis that in many patients with BEB there is a sympathetically maintained pain syndrome associated with external ocular disease. We speculate on a neurologic circuit that may explain these findings.

Anesthetics, Local↗
PubMed1999

Clinical characteristics and service use of persons with mental illness living in an intermediate care facility.

OBJECTIVE: The study examined the characteristics of residents living in a 450-bed intermediate care facility for persons with severe mental illness in Illinois and sought to determine the factors predicting their utilization of mental health services. METHODS: Data on 100 randomly selected residents with a chart diagnosis of schizophrenia were collected using chart review and interviews. Data for 78 residents whose diagnosis of schizophrenia or schizoaffective disorder was confirmed using the Structured Clinical Interview for DSM-IV were included in the analyses. RESULTS: Fifty-three percent of the residents used facility-based specialty mental health services beyond medication management, such as group therapy or a day program. Persons with the least severe psychiatric illnesses and with higher levels of motivation for overall care used the most mental health services. Thirty-five percent of the residents had been discharged to an inpatient psychiatric unit during the previous year. Residents most likely to be discharged to those settings were young men with a history of homelessness who refused facility-based health services. CONCLUSIONS: Despite recent policy-driven efforts to improve care in this intermediate care facility for persons with mental illness, the facility continues to have problems addressing the mental health needs of the residents.

Adult↗
PubMed1998

Heat shock protein 72 modulates pathways of stress-induced apoptosis.

The resistance to stress-induced apoptosis conferred by the thermotolerant state or by exogenous expression of HSP72 was measured in mouse embryo fibroblasts. The induction of thermotolerance protects cells from heat, tumor necrosis factor alpha (TNFalpha), and ceramide-induced apoptosis but not from ionizing radiation. Because the development of thermotolerance is associated with increased levels of heat shock proteins, we determined whether constitutive expression of one of the major inducible heat shock proteins, HSP72, could also protect cells from stress-induced apoptosis. Cells expressing constitutive HSP72 were shown to have significantly reduced levels of apoptosis after heat, TNFalpha, and ceramide but not after ionizing radiation. Activation of stress-activated protein kinase/c-Jun N-terminal kinase (SAPK/JNK) was found to be strongly inhibited in thermotolerant cells after heat shock but not after other stresses. Cells that constitutively express HSP72 did not demonstrate decreased SAPK/JNK activation after any of these stresses. Thus, factors other than HSP72 that are induced in the thermotolerant state are able to reduce activation of SAPK/JNK after heat stress. Notably, the level of activation of SAPK/JNK did not correlate with the amount of apoptosis detected after different stresses. Constitutive HSP72 expression inhibited poly(ADP-ribose) polymerase cleavage in cells after heat shock and TNFalpha but not after ceramide or ionizing radiation. The results suggest either that SAPK/JNK activation is not required for apoptosis in mouse embryo fibroblasts or that HSP72 acts downstream of SAPK/JNK. Furthermore, the data support the concept that caspase activity, which can be down-regulated by HSP72, is a crucial step in stress-induced apoptosis. Based on data presented here and elsewhere, we propose that the heat shock protein family can be classified as a class of anti-apoptotic genes, in addition to the Bcl-2 and inhibitor of apoptosis protein families of genes.

Animals↗