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Biomedical subjects

S Hollingsworth

Publications and source records attributed to S Hollingsworth.

13 recordsLinked to original sources
PubMed1997

In vitro immune modulation by antibodies coupled to tumour cells.

Modification of autologous tumour cells to express the immune costimulator B7.1 is a potential strategy for immunotherapy of cancer. Previously, this has involved introduction of genetic material into cells, in vitro culture, and confirmation of the protein product on the cell surface. This is possible only if sufficient tumour is obtainable and efficiently modified in a short time. Whilst progress has been made on ex vivo tumour cell culture and transfection/infection procedures there are still tumour types for which the present means of gene transfer are not efficient enough. We describe a highly efficient in vitro procedure for the modification of over 99% of the cells in a population, allowing the expression of cell surface proteins with potential immune modulatory activities. This procedure, which can be completed in as little as 24 h with no upper limit on cell number, utilizes succinimide esters to label cell surface proteins with biotin covalently. Biotinylated cell membrane proteins then anchor an avidin bridge for immobilizing protein G'-biotin. This can serve to bind immunoglobulin (Ig) molecules via their Fc region such that the variable region of the antibody is freely and functionally available. In the present study the binding of a stimulatory mouse anti-human CD28 monoclonal antibody to the surface of tumour cells is used to show that the modified cells are capable of co-stimulating T cells in vitro. The simplicity of the method, and the use of common reagents, represents a further step towards a realistic, truly 'off-the-shelf', nongene immunotherapy protocol.

Animals↗
PubMed1992

[The uveodermatologic syndrome in dogs].

A review of the literature pertaining to the uveodermatological syndrome of dogs is presented. This syndrome is marked by depigmentation of the periocular region, lips and nose in association with severe uveitis. Early diagnosis and therapy can prevent serious vision loss. Symptoms and therapy of the cases described in the literature as well as cases seen at the Veterinary Medical Teaching Hospital in Davis/California are discussed.

Animals↗
PubMed1991

Opioid binding in the rostral hypothalamus is reduced following lesion of the ventral noradrenergic tract in female rats.

Experiments were undertaken to establish whether opioid receptors exert a direct presynaptic influence on noradrenergic (NA) terminals in the preoptic/anterior hypothalamus (PO/AH) of the female rat. Thus, opioid binding studies were performed in rats with lesions of the ventral NA tract (VNAT; the main NA projection to the hypothalamus) to assess whether a loss of NA terminals may also result in a decrease in opioid binding in the PO/AH. In the first experiment, unilateral electrolytic lesions of the VNAT caused a significant reduction in both the NA content and specific [3H]-diprenorphine binding to membrane homogenates in the ipsilateral PO/AH. In the second experiment bilateral 6-hydroxydopamine (6-OHDA)-induced lesions of the VNAT caused a significant reduction in NA levels in the PO/AH as well as significant decreases in the density of [3H]-diprenorphine binding to tissue sections of the PO/AH when compared to control animals. These results strongly suggest that the NA input to the PO/AH is regulated by endogenous opioid peptides, and provide an anatomical substrate to explain opioid-NA interactions in the control of gonadotrophin releasing hormone (GnRH) and gonadotrophin secretion.

Animals↗
PubMed1988

Opioid peptides inhibit noradrenergic transmission in the preoptic area to block LH secretion: evidence from neonatally androgenised rats.

A series of experiments are described which show (a) that the release of noradrenaline in the preoptic area of rats is regulated by a presynaptic opioid receptor and, (b) that changes in the opioid control of preoptic noradrenaline release are associated with the anovulatory condition found in adult female rats which have been exposed to androgen neonatally. The experiments support the hypothesis that opioid-noradrenergic interaction in the preoptic area is an important component in the neural mechanism regulating gonadotrophin secretion.

Action Potentials↗
PubMed1988

Endogenous opioid actions and effects of environmental disturbance on parturition and oxytocin secretion in rats.

Blood samples were taken from conscious, chronically-catheterized rats during parturition for measurement of oxytocin by specific radioimmunoassay. After the birth of the 3rd pup, rats were allowed to remain in their nesting cage (undisturbed rats) or were transferred for 45 min to a glass bowl (disturbed rats); at the time of transfer, rats were given an i.v. injection of the opioid antagonist naloxone or saline vehicle. Subsequent parturition was prolonged in saline-treated disturbed rats, but not in naloxone-treated disturbed rats. Parturition was significantly hastened in naloxone-treated undisturbed rats. Naloxone injections were followed by a large rise in plasma oxytocin concentrations in disturbed and undisturbed rats. We conclude, from a statistical analysis of the relationship within experimental groups between plasma oxytocin concentration and speed of parturition, that the effects of disturbance and of naloxone upon parturition may be accounted for, at least in part, by their effects upon oxytocin release. However, the effects of disturbance on parturition may not be mediated entirely by activation of opioid pathways. Naloxone did not potentiate oxytocin release in non-pregnant rats, or on Day 1 post partum, but did potentiate oxytocin release on Day 22 of pregnancy even in rats before the onset of parturition. Endogenous opioid pathways regulating oxytocin release therefore appear to be active during late pregnancy and during parturition itself.

Animals↗
PubMed1987

Stress-induced disruption of parturition in the rat may be mediated by endogenous opioids.

Plasma samples were obtained before and during parturition from conscious rats implanted chronically with a jugular cannula. Rats were either allowed to remain in their nesting cage throughout parturition, or were moved immediately following the birth of the second or third pup into an empty glass chamber. The time-course of parturition was prolonged for mother rats which were moved in mid-parturition to this unfamiliar environment. However, in rats given an i.v. injection of the opioid antagonist naloxone at the time of transfer, parturition followed a normal time-course, and plasma oxytocin levels were significantly higher than in animals injected with saline. Thus our hypothesis is that stress activates opioid pathways which delay parturition by inhibiting oxytocin release. Opioid-mediated mechanisms may similarly be responsible for some problems in human parturition.

Animals↗
PubMed1986

The nursing process: implications for curriculum planning.

The focus of this paper is an exploration of the implications for curriculum planning of adopting the nursing process; which, it is suggested, represents the most far-reaching innovation in British nursing of recent years. An examination of the abilities required by nurses in order for them to deliver care in this way shows that to encompass the philosophy of the nursing process, fundamental changes need to be made in the way nurses are prepared in schools of nursing. In particular, to those elements of the curriculum dealing with content and teaching methods.

Communication↗
PubMed1985

Arthroscopic treatment of medial shelf syndrome.

Medial shelf or "plica" syndrome is a pathological condition of the knee that often follows knee injury in young athletes, the symptoms of which often mimic other internal derangements of the knee. Its anatomy, pathomechanics, and clinical presentation along with treatments suggested in the orthopedic literature are reviewed here. Two-year follow-up studies on the treatment of this syndrome by arthroscopic resection in 51 knees in 42 patients are presented as well.

Adult↗
PubMed1984

Arthroscopic evaluation and treatment of patellar malalignment.

The present retrospective study evaluates the clinical, arthroscopic, and follow-up findings in 37 patients with patellofemoral pain syndrome suspected to be a result of patellar tracking abnormality without patellar instability. The results indicate that arthroscopic evaluation of patellofemoral motion is an accurate way to define patellar malalignment. Arthroscopic lateral release gave satisfactory results in 39 of 43 knees. Unsatisfactory results were associated with chondromalacia, prolonged effusion, or painful crepitation.

Adolescent↗
PubMed1982

Partial arthroscopic meniscectomy: a preliminary report.

Short-term follow-up in 45 cases of meniscal derangement treated by partial arthroscopic meniscectomy was encouraging. Horizontal cleavage lesions and complex combination tears gave relatively few satisfactory results and resulted in two patients requiring reoperation. Emphasis must be placed on a careful evaluation of the meniscal remnant with a probe to ascertain the stability of the remainder of the meniscus to avoid this problem. Preexisting ligamentous instability when combined with degenerative change also caused fewer than expected satisfactory results. Careful patient selection and counseling may help to prevent this problem in the future. Age did not seem to affect the short term results. It should be emphasized that arthroscopic surgery requires a surgeon with extensive experience and adequate equipment in order to provide a comprehensive evaluation and treatment of the pathologic condition.

Adolescent↗
PubMedDate not supplied

Student perceptions of total quality.

The authors report how a college has attempted to gauge the perception of its 'consumers' on the quality of service they are providing. Using the results of a questionnaire survey of its students, the college is now able to incorporate the students' views into its total quality management initiatives.

Communication↗