A demonstration of generalization of performance across settings, materials, and motor responses for students with profound mental retardation

A treatment package, consisting of multiple exemplar training and community-based instruction, was evaluated for its effectiveness in teaching four students with profound mental retardation and multiple disabilities to participate in two sets of community-living tasks. All training took place in community settings, and each student demonstrated improved performance on at least one task set. In addition, all students demonstrated improved performance on a series of tasks selected to assess generalization of performance across settings, materials, and/or motoric responses required to complete the target task. Maintenance of performance over a 4- to 5-month period was assessed and achieved for two of the students. The results of this investigation are discussed in terms of the implications for programming for students with profound mental retardation.     

Norepinephrine in urine and plasma following provocative maneuvers in normal and hypertensive subjects

Urinary norepinephrine (UNE) excretion rate and venous plasma norepinephrine (PNE) concentrations were studied in 266 normotensive and 107 essential hypertensive men and women under conditions of volume expansion with 2 liters of intravenous normal saline over 4 hours, and volume contraction with a 10 mEq sodium diet and 120 mg oral furosemide. The UNE excretion rate was correlated with age in normal women only. In men, and in hypertensives of both sexes, the relationship appeared to be biphasic. The PNE concentration was not correlated with age in the hypertensive subjects. Insufficient numbers of older subjects were available to exclude absolutely such a relationship among normals. The UNE and PNE were influenced by volume expansion and contraction in both normals and hypertensives; however, normals exhibited a correlation between UNE and blood pressure as well as consistent correlations between UNE and PNE, neither of which were observed in the hypertensives. Hypertensive women generally had greater UNE and PNE values than normal women or hypertensive men. Hypertensive women may have altered sympathetic activity.     

Long-term ovarian and gonadotropin changes in mice exposed to 4-vinylcyclohexene

This study investigated the relationships between 4-vinylcyclohexene-induced follicular destruction, plasma FSH levels, and the development of ovarian preneoplastic changes. Female, 28-day-old, B6C3F1 mice were administered VCH (800 mg/kg/day, ip) or sesame seed oil, ip daily for 30 days. At 30, 60, 120, 240, and 360 days following the beginning of treatment, groups were killed, their ovaries were harvested, and plasma was collected for measurement of FSH. Ovarian weight was less and oocytes contained in preantral follicles were significantly fewer than controls at all time points. Plasma FSH concentrations in VCH-treated animals were increased significantly above controls at 240 d and 360 d. Histologically, there was oocyte loss at all times, whereas at 240 and 360 days, small to medium, irregularly shaped foci of hypertrophic cells were present. In addition, at 360 days 80% of the VCH-treated mice had a 1- to 2-mm, blood-filled cystic structure present in one or both ovaries. These studies indicate that VCH-induced oocyte destruction and follicle loss are associated with increases in plasma FSH, are associated with ovarian failure at 360 days, and are temporally related to ovarian cellular hypertrophy and the formation of blood-filled cystic ovarian structures. These events are possibly related to ovarian neoplasms produced by long-term exposure to VCH.     

Influence of factors released from sciatic nerve on adult dorsal root ganglion neurons

Previous experiments have shown that medium conditioned (CM) by denervated peripheral nerve contains a process outgrowth promoting factor(s) for cultured adult frog dorsal root ganglion (DRG) neurons. The present experiments further characterize the influences of these factors on DRG neurons. The growth factors increases average process length by threefold, restricts the number of processes extended from four to two while simultaneously altering the morphology of those processes. Neurons with preexisting processes respond to the factors by significantly increasing the length of 35% of these processes. Only the newly elongated portions of preexisting processes have a morphology typical of factor-induced processes, while the previously extended portions retain their original morphology. The number of processes of these neurons remains unchanged. Although composed of two populations according to size, neurons in both populations are similarly influenced, suggesting that the factors influence neurons of all sensory modalities. To look at other possible influences of the nerve-released factors, a novel simple culture system has been developed in which concentration gradients of these factors can be established and maintained. The front of the outgrowth-promoting influence in these cultures could be followed over time (up to 9 days) as it affected the process length and morphology of neurons at increasing distances (up to 8 mm) from the source of the factors. The trophic factors may play important roles during regeneration in vivo by influencing the cytoskeletal organization in the cell body and growth cones to bring about a stabilization and consolidation of growth cone membrane of only a limited number of processes resulting in increasing the rate of process elongation. The factors may also serve to direct process outgrowth, which can be examined using the new culture system.     

1H NMR studies of the high-affinity Rev binding site of the Rev responsive element of HIV-1 mRNA: base pairing in the core binding element

1H NMR studies of a 30-nucleotide RNA oligonucleotide (RBE3), which contains a high-affinity binding site for Rev of the HIV-1 Rev responsive element (RRE), two derivatives of RBE3 (RBE3AA and RBE3-A), and the complex of RBE3 with peptides derived from the RNA binding domain of HIV-1 Rev, are presented. The high-affinity binding site of the RRE consists of an asymmetric internal loop and surrounding Watson-Crick base pairs. In the wild-type RRE, one of the stems is closed by a loop; this is replaced in REB3 by the stable UUCG tetraloop. NOE data suggest that the internal loop of the free RNA contains structural features that have been predicted on the basis of in vitro selection experiments [Bartel, D.P., et al. (1991) Cell 67, 529-536]. The structural features include a Gsyn.Ganti base pair, a Ganti.Aanti base pair, and a looped out U. When the Rev peptide is bound to the RNA, the base pairs in the internal loop appear to be stabilized, although the RNA chemical shifts indicate that the RNA conformation undergoes some changes when bound by Rev peptide.     

Intraoperative radiotherapy of unresectable pancreatic carcinoma

During the period from 1986 to 1991, 33 patients with unresectable carcinoma of the pancreas received intraoperative radiotherapy (IORT). Abdominal and back pain which tormented all patients before IORT totally disappeared in 18 patients (54%) and was allevrited in 13 patients (40%). The average survival time of 6.5 months for patients treated with IORT was not statistically different from that of 30 patients with resectable pancreatic cancers undergoing resection. IORT hence is a good palliative therapy for unresectable carcinoma of the pancreas.     

Vitiligo, psoralen, and melanogenesis: some observations and understanding

Since the etiology of vitiligo is still unknown, we searched for some abnormal biochemical parameters, if any, in subjects with vitiligo. Higher urinary excretion of indole metabolites in vitiliginous patients have been noted, in association with higher dioxygenase, superoxide dismutase, and tyrosine aminotransferase activity in their serum. Similar results have also been found in an animal model, Bufo melanostictus, during induced tyrosinase inhibition. Treatment with psoralen can reverse the parameters, except tyrosine aminotransferase, to a normal level. Although psoralens are not the magic bullet for the therapy of vitiligo, they are still being used as a chemotherapeutic agent against vitiligo on a major scale to date. Tryptophan was found to participate in the pathway of melanogenesis, as a precursor as well as a positive regulator of tyrosinase. Its behavior in this regard is much more similar to the conventional substrates tyrosine and dopa (dihydroxyphenylalanine). In consideration of combined participation of tyrosine and tryptophan in the synthesis of melanin and its breakdown, the possible influence of different enzymatic reactions, like mono-oxygenase, dioxygenase, and deamination, has been suggested.     

Female pseudohermaphroditism due to congenital adrenal hyperplasia complicated by adenocarcinoma of the prostate and clear cell carcinoma of the endometrium

The presence of prostatic glandular tissue in female pseudohermaphrodites has previously been documented. However, prostatic neoplasia in this clinical setting has not been reported. A karyotypic female with congenital adrenal hyperplasia due to 21-hydroxylase deficiency developed a prostatic adenocarcinoma associated with elevated serum prostatic specific antigen levels and osteoblastic skeletal metastases. This demonstrates that this tissue in pseudohermaphrodites can become malignant. In addition, the patient subsequently developed clear cell carcinoma of the endometrium, possibly related to radiation therapy for the prostatic adenocarcinoma. This demonstrates that female pseudohermaphrodites may be at risk not only for malignancies seen in genotypic females but also prostate cancer.