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The effects of chronic adolescent fluoxetine (FLX, Prozac®) exposure on adult cognition are largely unknown. We used a serial multiple choice (SMC) task to characterize the effects of adolescent FLX exposure on rat serial pattern learning in adulthood. Male rats were exposed to either 1.0, 2.0, or 4.0 mg/kg/day FLX for five consecutive days each week for five weeks during adolescence, followed by a 35-day drug-free period. As adults, the rats were trained in a task that required them to learn a highly structured sequential pattern of responses in an octagonal chamber for water reinforcement. In a transfer phase, the terminal element of the pattern was replaced by a violation element that was inconsistent with previously learned pattern structure. Results indicated that adolescent FLX exposure caused differential learning deficits for different types of elements in the serial pattern. Adolescent exposure to 1.0 or 4.0 mg/kg/day FLX, but not 2.0 mg/kg/day FLX, impaired chunk-boundary element learning, which is known to be mediated by stimulus-response (S-R) learning. All three doses of FLX impaired violation element learning, which is known to be mediated by multiple-cue learning. FLX did not impair within-chunk element learning, which is known to be mediated by rule-learning mechanisms. The results indicate that adolescent FLX exposure produced multiple cognitive impairments that were detectable in adulthood long after drug exposure ended.

Serial pattern learning is a model paradigm for studying parallel-processing in complex learning in rats. The current experiment extends the paradigm to the study of sequential memory by examining forgetting curves for the component element types that make up a serial pattern. Adult male and female rats were trained in a serial multiple choice (SMC) task in which rats learned a serial pattern of nose-poke responses in a circular array of 8 receptacles mounted on the walls of an octagonal operant chamber. The pattern was 123-234-345-456-567-678-781-818, where digits represent the clockwise positions of successive correct receptacles. Previous work has shown that chunk-boundary elements (the first element of each 3-element chunk), within-chunk elements (the second and third elements in all but the last chunk), and the violation element (the last element of the pattern) are learned via different cognitive mechanisms. After each rat was trained to an 85% correct performance criterion on the violation element, we then assessed serial pattern retention at 24-h, 2-week, and 4-week retention intervals. For chunk-boundary and within-chunk elements, forgetting was observed only at the 4-week retention interval. Sex differences were observed; females performed better than males on within-chunk elements at 24-h and 4-week retention intervals. For the violation element, significant forgetting was observed earlier at the 2-week retention interval as well as at the 4-week retention interval. Thus, pattern elements that were learned slower were forgotten faster. The experiment provides a proof of concept for evaluating forgetting curves separately for the multiple memory systems rats appear to employ concurrently in this paradigm, a method that may prove useful in characterizing the impact of relevant neurobiological manipulations on forgetting in multiple sequential memory systems.

Giant cell tumor of bone, comprising approximately 5% of all primary bone neoplasms, is a fascinating enigma. Histologically the tumor shows a wide range of morphology and its clinical behavior is unpredictable: histologic grading of giant cell tumors, as devised by Jaffe and others [5,7], has been ineffective in prognosticating the aggressiveness and recurrence ofthe tumor. Treatment is controversial: curettage and bone grafting has resulted in a 40%–60% recurrence rate [2,3,8]. Inadequate treatment may result in local soft tissue recurrence, high morbidity, metastasis, or even mortality. Wide en bloc resection for aggressive lesions is associated with high morbidity, often severely affecting or sacrificing joint function. This study reports our experience with 20 patients treated by curettage and polymethylmethacrylation.

Five strains of Escherichia coli were tested for the presence of the K88ac or K88ab antigens by immunoelectrophoresis and immunodiffusion. The K88ac antigen of 0A2 and Sojka Abbotstown gave an anodic line in the immunoelectrophoresis test and a line in immunodiffusion with homologous K88ac antisera. The K88ab antigens of 0G7, 0E68, and Moon 263 also gave anodic lines in immunoelectrophoresis, and were detectable by immunodiffusions. The 0 groups of these strains were also demonstrated by immunoelectrophoresis and immunodiffusion with homologous 0 antisera. Lack of complete inactivation at 100 degrees C of both the K88ac and K88ab antigens was noted in this study.

High resolution agarose isoelectric focusing was used to compare the galactosyltransferase isoenzyme patterns of serum from 9 healthy controls with those from 38 patients with either breast, lung, ovarian, stomach or colonic cancer. At least 12 peaks of enzyme activity were found in every sample, the healthy controls having major forms with isoelectric points of 4.74, 4.87, 4.96, 5.16 and 5.23. Thirty patients (79%) had elevated levels of at least one isoenzyme and 23 (61%) had at least 3 isoenzymes elevated compared to only 10 (26%) patients who had elevated total serum galactosyltransferase activity. The isoenzymes which were most often elevated in the cancer patient group had isoelectric points of 4.93, 5.16 and 4.61. One isoenzyme with an isoelectric point of 4.43 was preferentially elevated in patients with ovarian cancer. Those isoenzymes containing little or no sialic acid were rarely elevated in cancer patients. Although no cancer-associated isoenzyme was detected the quantitative differences observed in the cancer patient group were striking.

Public awareness of the increasing stress on the environment caused by population and economic growth and rising standards of living has led to many desirable regulations limiting pollution. However, some such regulations would provide little, if any, environmental benefit, would be costly to consumers and are technically unsound. Laws which impose penalties on oil spillers based on unquantified damages fall in this counterproductive class. Such laws are ill-conceived and unwarranted. Alaska, for example, has adopted regulations with explicit high penalties on oil spills without any requirement that damage be demonstrated or quantified. Other states have similar laws under consideration. Even where such laws purport to base penalties on estimated loss of organisms, the basis for demonstrating and quantifying such loss is arbitrary and judgmental. As demonstrated many times, the marine environment can restore itself in relatively little time. Existing laws already provide for compensation of actual damages which may result. The authors are of the opinion that laws such as Alaska's would do little but raise consumer prices and discourage needed petroleum supplies. Further, such laws are contrary to our legal philosophy that the fact and the extent of injury must be proven before damages can be claimed.

A series of 32 cases in which crush preparations were used in addition to frozen sections for the rapid diagnosis of lesions of the central nervous system (CNS) is presented. The cytopathologic features in crush preparations of astrocytomas, glioblastomas multiforme and a pituitary adenoma are described. Excellent preservation of cellular detail was seen in the crush preparations. Frozen sections lacked cytologic detail but provided a better view of the tissue architecture. The crush preparations yielded the correct diagnosis in 29 of the 32 cases. In the other three, a secondary component of the neoplasms (oligodendroglioma and fibrosarcoma) was identified only in the paraffin sections. Use of both frozen sections and crush preparations is recommended for all cases in which an immediate diagnosis of a CNS lesion is required.

The serum level of galactosyltransferase was measured in a group of 218 patients with a variety of solid tumors and most with advanced disease. The pretreatment enzyme level showed little potential as a diagnostic tumor marker, and its change with treatment did not reflect the initial response. There was, however, a significant correlation between the length of survival and the pretreatment enzyme level. Patients with normal levels survived over twice as long as those with elevated levels. When Cox's proportional hazards regression analysis was used to compare the prognostic potential of galactosyltransferase with a number of known clinical indicators of prognosis, the variable most related to survival was performance status (P less than 10(-4) followed by galactosyltransferase (P = 0.01) and then the extent of disease (P = 0.03). The other variables, such as previous therapy, the type, site, and size of primary tumor, did not contribute significantly to the relationship with survival. The pretreatment level of galactosyltransferase is therefore a relatively independent prognosticator of survival and, as such, could be potentially useful in patient management by increasing the accuracy of the initial assessment of prognosis.

THIS PAPER PRESENTS THE OUTLOOK FOR GASOLINE SUPPLY AND DEMAND IN THE UNITED STATES AS NOW ENVISIONED. IT INCLUDES DISCUSSIONS OF PRESENT OIL SUPPLIES AS WELL AS FUTURE ONES, OF REFINERY CAPACITY AND ITS PROJECTED SHORTAGE, AND OF GASOLINE CONSUMPTION AND SUPPLY THROUGH 1976 AND BEYOND. WITHOUT GOVERNMENT AND PUBLIC SUPPORT, IT IS DOUBTFUL THAT THE NECESSARY REFINERY CAPACITY CAN BE ACCOMPLISHED. /AUTHOR/