Learned changes of feeding behavior in Aplysia in response to edible and inedible foods

Feeding behavior in Aplysia fasciata and A. oculifera is modified by pairing the behavior with reinforcing consequences. Successful and unsuccessful attempts to transfer food from the buccal cavity to the crop act as positive and negative reinforcers, respectively. A number of changes in feeding behavior occur as a result of pairing of feeding with the negative reinforcer: feeding responses become less effective in leading to the entry of food into the buccal cavity; when food does enter the buccal cavity, it exits sooner; swallowing responses after food entry are less likely to occur; Aplysia eventually cease responding to food. Pairing successful transfer of food into the crop with feeding behavior produces opposite effects. Behavioral change is specific to pairing, as shown by lack of change when reinforcement is explicitly unpaired with feeding behavior. Behavioral change is specific to foods with a particular taste and texture; generalization to alternate foods was not observed. In spite of cessation of feeding, animals remain aroused, as shown by low response latency to alternate foods. Memory of response change persists for at least 48 hr.     

CT appearance of cervical lipoblastoma

We describe a case of lipoblastoma causing respiratory symptoms in an infant, where CT was useful in establishing the diagnosis and demonstrating the extent of involvement so that complete surgical resection could be planned.     

Metaproterenol (Alupent) metered dose inhaler in children 5-12 years of age

This multiclinic study was performed to evaluate the safety and efficacy of metaproterenol sulfate (Alupent) metered dose inhaler in children with asthma ages 5 to 12 years. A total of 268 children completed this study according to the protocol, having received either metaproterenol or placebo for 30 consecutive days. Full spirometric testing was done pre- and postdose on Days 1 and 30 for a total duration of 6 hours on each day. The results showed that metaproterenol was consistently superior to placebo in all pulmonary function parameters measured on Days 1 and 30. This difference was statistically significant for peak values and areas under the curves for both FEV1 and FEF25-75%. There were no significant side effects noted. We conclude that metaproterenol metered dose inhaler is safe and effective in the treatment of asthma in children ages 5 to 12 years.     

T-cell subset analysis of Lewis lung carcinoma tumor rejection: heterogeneity of effectors and evidence for negative regulatory lymphocytes correlating with metastasis.

We have analyzed the phenotypes of the T-cell subsets generated in response to Lewis lung carcinoma clones in C57BL/6J recipients. The metastatic derivative, which expresses low levels of H-2Kb gene, predominantly elicited CD8, V beta 8, and V beta 9+ T-cells. The nonmetastatic clone expressing high levels of H-Kb gene triggered a more heterogeneous response of V beta-5, -6, -8, -9, and -11 CD8+ T-cells. Comparison of the T-cell receptor (TCR) expression of the T-cells infiltrating the tumor site with the lymphocytes in the periphery of tumor-bearing animals revealed a pattern of homing of CD4+ T-cells bearing V beta-5, -6, and -11 TCR chains and CD8+ T-cells bearing V beta-5, -6, -9, and -11. Depletion of V beta 5 or V beta 6+ T-cells correlated with accelerated tumor growth, implying their protective role as tumor-specific effectors and consistent with the cytotoxicity of T-cells with this TCR phenotype. V beta 11 TCR expression in the tumor-infiltrating lymphocytes increased with the tumor size. Depletion of V beta 11+ T-cells enhanced resistance to primary tumor growth and conferred protection from metastasis in recipients cleared of V beta 5 and V beta 6 T-cell subsets. Those results suggest that tumor-specific effectors as well as negative regulator T-cells home, infiltrate, and coexist in the tumor site.     

Phaeohyphomycotic cutaneous disease caused by Pleurophoma in a cardiac transplant patient

A 56-y-old female cardiac transplant patient treated with cyclosporine and prednisone noted the onset of three nontender red nodules on the legs and arms after gardening. Biopsy of all lesions revealed inflammatory cells and hyphal elements in the dermis. The dematiaceous fungus cultured from biopsy tissue was a pycnidial-forming organism of the genus Pleurophoma. The lesions responded to the topical application of miconazole.     

Firearm and nonfirearm homicide among persons 15 through 19 years of age. Differences by level of urbanization, United States, 1979 through 1989.

OBJECTIVE--To examine trends (1979 through 1989) and current status in firearm and nonfirearm homicide rates by level of urbanization among persons 15 through 19 years of age. DESIGN--The Compressed Mortality File, a county-level mortality and population database maintained by the National Center for Health Statistics, Centers for Disease Control, Hyattsville, Md, and the 1980 Human Resource Profile County Codes are used to analyze age-, sex-, and race-specific firearm and nonfirearm homicide rates by urbanization level. SETTING--United States, 1979 through 1989. SUBJECTS--Black and white males and females 15 through 19 years of age whose underlying cause of death was either firearm homicide (E965.0 through E965.4 or E970) or nonfirearm homicide (E960 through E964, E965.5 through E969, or E971 through E978) in the ICD-9 (International Statistical Classification of Diseases, Injuries, and Causes of Death, Ninth Revision). MAIN OUTCOME MEASURES--Urbanization level-specific firearm and nonfirearm homicide rates. RESULTS--The 1989 firearm homicide rate in metropolitan counties was nearly five times the rate in nonmetropolitan counties (13.7 vs 2.9 deaths per 100,000 population). Firearm homicide rates were highest in core metropolitan counties, 27.7 per 100,000 population; rates were higher for black males than for any other race-sex group in each of five county urbanization strata for 1979 through 1989. Nonfirearm homicide rates are considerably lower, with smaller urban differentials; the rate in metropolitan counties was 1.4 times the rate in nonmetropolitan counties (2.6 vs 1.8 per 100,000 population). From 1979 through 1984, firearm homicide rates declined in each of the county strata. From 1984 through 1987, firearm homicide rates increased, and from 1987 through 1989 they increased rapidly, from 23% to 35% per year in the four metropolitan strata. From 1979 through 1989, nonfirearm homicide rates declined or remained stable. CONCLUSIONS--Large urbanization differentials in firearm homicide and smaller differentials in nonfirearm homicide are identified. Firearm homicide rates are highest and increasing the fastest among black teenage males in the core, fringe, and medium metropolitan strata.