Hamster pancreas acinar cell post-differentiation antigen detected by murine monoclonal antibody

Summary For identification of hamster acinar cells, murine monoclonal antibodies to dispersed adult hamster acinar cells were developed. One of these, Ham-Acl, with strong affinity for a membrane-associated adult acinar cell antigen, was purified by HPLC, isotyped as IgG₁ and used for the characterization of a species-specific, immunoprecipitable post-differentiation antigen on adult acinar cells. This antigen of 98 kDa was identified on paraffin sections of adult hamster acinar cells by an indirect immunofluorescence technique. It was undetectable in fetal hamster pancreas, but was present on 2-week-old and older hamster acinar cells.     

Double-blind assessment of stimulant medication for attention deficit disorder: a model for clinical application

A double-blind procedure is presented for assessing the response to stimulant medication among children with attention deficit disorder. Of 94 children treated with methylphenidate and placebo, 70 demonstrated a positive response to active medication. It is suggested that a double-blind investigation is an efficient means of securing meaningful treatment information, particularly in difficult family or clinical situations.     

Effects of nicotine and its withdrawal on the performance of rats on signalled and unsignalled avoidance schedules

Rats were trained while under the influence of nicotine on a Sidman avoidance schedule. When saline was substituted for nicotine the animals which had been trained on an unsignalled schedule showed poor avoidance and took significantly more shocks than their saline-trained partners. When the schedule included either a warning signal preceding each shock or a feedback signal following each response this dependence did not develop. It is suggested that dependence on nicotine is related to the stressfulness of the situation and that the behavioural disruption found in its absence is due to an accentuation of the normal warmup process and not to dissociation of learning.     

The response of turkey poults to experimental infection with strains of M. gallisepticum of different virulence and with M. gallinarum

In turkey poults aged up to 28 days, a virulent S6 strain of M. gallisepticum was recovered more frequently from more tissues for a longer time than were other strains. The virulent strain caused nervous signs and gross brain lesions in poults, and was often isolated from the brain, suggesting its neurotropism. All M. Gallisepticum strains were isolated from the synovial fluid of hocks, but swollen hocks and foot pads were seen only in poults infected with the A514 strain. It would seem, therefore, that although proclivity for joints was shown by all strains, only A514 produced grossly pathogenic effects in these young birds. All strains of M. gallisepticum showed some proclivity for respiratory tissues. Signs, gross lesions and recoveries of mycoplasma frequently failed to correlate. Perosis was seen in only two poults; these were infected with M. gallinarum with which the condition may, or may not, be associated. Serological reactions to both the rapid serum agglutination and haemagglutination inhibition tests developed in the 3rd and 4th weeks of life in all poults infected with M. gallisepticum strains although false positives and negatives were recorded. The main results of infection with the strains in turkey poults and in a similar study in chicks are summarised.     

Social constructionism and medical sociology: a study of the vascular theory of multiple sclerosis

Abstract M.R. Bury has radically questioned the value of social constructionism for medical sociology (1986). The present authors have already responded to this wide-ranging critique (Nicolson and McLaughlin 1987). This article aims to complement our theoretical discussion by embodying its principles in empirical case study. A recent debate surrounding the pathogenesis of multiple sclerosis is analysed in terms of the skills, interests and backgrounds of the medical personnel involved. It is noted that the proponents of the vascular theory possess developed expertises in interpreting disease in structural, vascular terms, whereas their opponents' skills lie in immunology or neurology. Different observers have produced different conceptions of the disease because modes of observation, and the points from which observation takes place, differ. It is also noted that the debate over the causation and treatment of MS has occurred between a large and powerful social group and a weak and marginal one. The effects of this power inequality on the production and assessment of knowledge about MS are investigated. The significance of the case study for Bury's misgivings as to the value of social constructionism is discussed, particular concern being taken to clarify the notions of instrumental realism, of reflexivity, and of the alleged dispensability of medicine.     

Preservation of the Latissimus Dorsi Muscle During Cardiomyoplasty Surgery

A bstract Background : Cardiomyoplasty surgery has been shown to be associated with damage and degeneration of the assisting skeletal muscle. The purpose of this study was to use ischemic (short-term) and thermal (long-term) preconditioning to protect the muscle during surgery and the subsequent ischemia. Methods : Three 10-minute cycles of ischemia-reperfusion were accomplished noninvasively on goat latissimus dorsi muscle (LDM) immediately prior to surgery. In another experiment, LDM was noninvasively heat shocked for 20 minutes at 42°C 24 hours prior to surgery. LDM damage was evaluated 5 days postsurgery using enzyme activities (β-glucuronidase, β-GLN; citrate synthase), hydroxyproline, morphology, and blood flow. Results : The lysosomal enzyme, β-GLN, was significantly increased (43%, p < 0.05) by surgical dissection and remained high in the ischemic preconditioned LDM (58%, p < 0.05) and in the heat shocked LDM (57%, p < 0.05). Conclusion : These findings show that these two protective protocols do not reduce the muscle damage that occurs during surgical preparation of the LDM for cardiomyoplasty.     

Effects of nicotine on the observed behaviour of rats during signalled and unsignalled avoidance experiments

Rats which had been chronically injected with nicotine or with saline during avoidance training were observed during subsequent avoidance experiments. Among those trained and tested on an unsignalled schedule lever-holding and crouching were frequent and the stimulant effects of nicotine, though consistent, were small. When a warning signal preceded each shock or a feedback signal followed each response lever-holding and crouching were reduced. In these experiments the rats tested with saline were inactive but they tended to lie down rather than crouch during their periods of immobility. Nicotine-treated rats in the signalled experiments were active with high levels of sniffing and grooming behaviour. It is suggested that the lever-holding and crouching in the unsignalled experiment were both aspects of freezing behaviour.     

Secretin and Autism: A Two-Part Clinical Investigation

Recent anecdotal reports have touted the gastrointestinal (GI) hormone secretin as a treatment modality for autism, though there is little clinical evidence or literature to support its viability. We undertook a two-part clinical trial to investigate these claims. Fifty-six patients (49 boys, 7 girls, mean age = 6.4 years, SD = 2.7) enrolled in an open-label trial of secretin, during which they received one injection of the hormone (2 IU/kg). All subjects were evaluated by their parents at baseline and follow-up visits (3–6 weeks later, M = 3.7, SD = 1.4 weeks) with Childhood Autism Rating Scales (CARS). Thirty-four patients were labeled with Pervasive Developmental Disorder Not Otherwise Specified, and 22 met diagnostic criteria for Autistic Disorder. Forty-five patients were concurrently on other drug treatments. At follow-up, some reported minimal but potentially significant improvements including changes in GI symptoms, expressive and/or receptive language function, and improved awareness and social interactions. No adverse effects were reported or observed. Subsequently, 17 of the most responsive patients from Study 1 began a double-blind trial that also included 8 newly enrolled patients. Patients in this second study were alternatively entered into one of two groups and received injections of secretin or placebo with crossover at 4 weeks. Patients from Study 1 entered into Study 2 at an average of 6.5 (SD = 0.8) weeks after beginning Study 1. Results of both inquiries indicate that although treatment with secretin was reported to cause transient changes in speech and behavior in some children, overall it produced few clinically meaningful changes when compared to children given placebo injections.     

Local anesthesia with intravenous sedation for surgical repair of selected open globe injuries

PURPOSE: To report factors associated with the use of local anesthesia with intravenous sedation (local anesthesia/sedation) rather than general anesthesia for surgery for open globe injuries in adult reparable eyes. DESIGN: Retrospective, nonrandomized, comparative case series. METHODS: Medical records were reviewed of all patients with open globe injuries repaired at Bascom Palmer Eye Institute between 1995 and 1999. "Adult reparable eyes" (eyes in patients >/=18 years of age, not treated with primary enucleation or evisceration, followed up >/=2 months) were included. RESULTS: In all, 220 eyes of 218 patients met inclusion criteria. General anesthesia was employed in 80 of 200 (36%) and local anesthesia/sedation in 140 of 220 (64%). Patients who had local anesthesia/sedation were significantly more likely to have an intraocular foreign body (31% vs 14%; P =.010, chi-square test), better presenting visual acuity (1.8 logMAR [logarithm of the minimum angle of resolution] units vs 2.5 logMAR units; P <.001, t test), more anterior wound location (75% corneal/limbal vs 65%; P =.003, chi-square), shorter wound length (6.3mm vs 10.8mm; P <.001, t test), and dehiscence of previous surgical wound (26% vs 12%; P =.021, chi-square) and were significantly less likely to have an afferent pupillary defect (22% vs 51%; P <.001, chi-square). There was no anesthesia-related complication in either group. The local anesthesia/sedation group had a shorter mean operating time than did the general anesthesia group (78 minutes vs 117 minutes; P <.001, t test). The general anesthesia group had a longer mean follow-up than the local anesthesia/sedation group (20.2 months vs 13.9 months, respectively; P =.002, t test). Change in visual acuity between the presenting and final examinations was similar for open globe injuries repaired with general anesthesia compared with local anesthesia/sedation (0.94 vs 0.72 logMAR units of visual acuity, respectively; P =.16, t test). CONCLUSIONS: Local anesthesia/sedation is a reasonable alternative to general anesthesia for selected patients with open globe injuries.