Nonrandomness of D-group chromosomes involved in centric-fusion translocation

Ten members of two families with D/G translocation, three members of a family with D/D translocation, and one patient with non-familial and one with apparently non-familial D/D translocation were examined. The trdnslocation chromosomes were identified by SH-thymidine labeling and autoradio-graphy as 14q21q and 13q14q, respectively. These findings support the hypothesis of nonrandomness of D group chromosomes involved in centric-fusion translocation. The importance of the identification of Dgroup chromosomes involved in centriofusion translocation in relation to genetic counseling is discussed.     

Evidence for nonsynaptic neuronal interaction.

1. Evidence is presented that synaptic interactions within and between the statocyst and visual pathways of Hermissenda are eliminated after 0.5-4 min exposure to 20-40 mM Co2+. 2. Synaptic blockade was also produced by perfusion with low Ca2+ (5mM) plus 10-20 mM Co2+. 3. Depolarization of hair cells by impulses of type A photoreceptors remains after the same exposure to Co2+, or low Ca2+ plus Co2+. 4. The increased resistance previously observed during this depolarization of hair cells cannot be observed after exposure to Co2+. 5. The depolarization which remains after exposure to Co2+ did not change with different levels of membrane potential from -20 mV below to +10 mV above the resting level. 6. The time course of potassium accumulation, monitored by the amplitude of the type A impulse afterpotential, closely followed the time course of hair cell depolarization and also of changes in the amplitude of the hair cell afterpotential. 7. The depolarization of hair cells by type A impulses decreased with increased extracellular potassium, but was only slightly reduced by lowered extracellular potassium. 8. The amount of potassium accumulation following a type A impulse train could be estimated from the effects of changes in extracellular potassium in the perfusate on the type A impulse afterpotential. From this extimated increase of extracellular potassium it was possible to predict with some accuracy, the observed hair cell depolarization. 9. Although type A cells are not electrically coupled to ipsilateral hair cells, firing of these hair cells slightly depolarized the type A photoreceptor which excites them. 10. Strophanthidin (10-4 M) did not block the depolarization of hair cells by type A impulses. 11. The data are evidence for nonsynaptic excitation of hair cells by type A photoreceptor impulses. The data are also consistent with the interpretation that the excitation arises from potassium accumulation around the type A and hair cell axonal membranes.     

Learning-induced enhancement of postsynaptic potentials in pyramidal neurons

We studied the effect of olfactory learning-induced modifications in piriform (olfactory) cortex pyramidal neurons on the propagation of postsynaptic potentials (PSPs). Rats were trained to distinguish between odors in pairs, in an olfactory discrimination task. Three days after training completion, PSPs were evoked in layer II pyramidal cells in piriform cortex brain slices by electrical stimulation of two pathways. Stimulation of layer Ib activated the intra-cortical fibers that terminate on the proximal region of the apical and basal dendrites. Stimulation of layer Ia activated the afferent axons that originate from the olfactory bulb and terminate on the distal apical dendrites. We have previously shown that olfactory training is accompanied by enhanced synaptic transmission in the intrinsic pathway, but not in the afferent pathway at 3 days after training. Here we show that at this stage, in both pathways PSPs evoked in neurons from trained rats had significantly faster rise time measured at the soma compared with PSPs in neurons from pseudo-trained and naive rats. Activation of the slow afterhyperpolarization (AHP), which is generated by potassium channels probably located at the proximal region of both apical and basal dendrites, reduced the amplitude measured at the soma of the proximal intrinsic pathway PSPs more effectively than PSPs that were generated distally by the afferent fibers. Thus the amount of reduction by AHP was used as a measure for the relative distance of PSP-generating sites from the soma. In neurons from trained rats, despite the previously reported reduction in AHP amplitude, AHP conductance shunted the PSPs from both synaptic pathways more efficiently compared with neurons from the control rats. We suggest that in neurons from trained rats PSPs are electrotonicly closer to the soma.     

The Athletic Prevention Programming and Leadership Education (APPLE) Model: Developing Substance Abuse Prevention Programs

Alcohol and other drug (AOD) abuse affects every sector of society, and student-athletes are no exception. Because many factors affecting athletes do not affect other students, athletic departments commonly approach prevention through AOD education. Different educational approaches are described in this article, particularly the Athletic Prevention Programming and Leadership Education (APPLE) model. Project APPLE is designed to enable an athletic department to systematically analyze its AOD prevention in seven areas: recruitment practices, expectations and attitudes, education and AOD programs, policies, drug testing, discipline, and referral and counseling. Because athletic trainers often are involved in this process, this article should help them to design more effective AOD programs.     

Factors influencing active avoidance behavior in rats with ventromedial hypothalamic lesions

Ventromedial hypothalamic lesioned rats maintained at preoperative body weight received an equal number of shocks while emitting significantly fewer responses than controls in a lever-pressing free-operant avoidance paradigm, and performed as well as unoperated animals in lever-pressing and shuttle box (both 1- and 2-way) discriminated avoidance tasks. The failure of VMH lesions to facilitate performance in the 2-way avoidance paradigm was probably the result of a ceiling effect. With the exception of the simple one-way avoidance task, obese lesioned rats were markedly impaired in the acquisition of all active avoidance behavior, but escape behavior was not affected. When tested in a free-operant paradigm, the avoidance performance of well trained lesioned animals varied inversely with body weight. As obese rats displayed lower flinch thresholds to shock than controls and similar levels of activity and responding as lean lesioned animals, it was concluded that their impaired avoidance behavior was not due to changes in sensitivity or mobility. The possible relation to other VMH lesion- and/or obesity-induced deficits is discussed.     

Follicular density in ovarian biopsy of infertile women: a novel method to assess ovarian reserve

The ageing ovary appears to be characterized by depletion of primordial follicles. The relationship between infertility and the number of follicles in the ovarian cortex is not known. Moreover, there are no accurate markers or clinical methods to predict the decline in ovarian reserve. This study investigates the correlation between early follicular follicle stimulating hormone, ovarian size and follicular density in 60 infertile women aged 19-45 years (mean = 34.4 +/- 5.5). An ovarian biopsy was taken from each patient while performing diagnostic laparoscopy (n = 28) or laparotomy for tubal surgery or myomectomy (n = 32). The median number of follicles was similar in tubal and unexplained infertility patients (9.5 versus 5.5). Increasing age showed a significant negative correlation with follicular density and ovarian volume (r = -0.46, P = 0.0003;. r = -0.43, P = 0.0016, respectively). In women > or = 35 years of age the ovarian volume showed a strong correlation with follicular density (r = 0.71, P < 0.0001). Our results indicate that infertile women in their late thirties and over have a decreased ovarian reserve which could possibly be predicted by ovarian volume measurement. Ovarian biopsy may have a place as part of infertility evaluation in older women.      

Involvement of helicase II (uvrD gene product) and DNA polymerase I in excision mediated by the uvrABC protein complex.

The bimodal-incision nature of the reaction of UV-irradiated DNA catalyzed by the Escherichia coli uvrABC protein complex potentially leads to excision of a 12- to 13-nucleotide-long damaged fragment. However, the oligonucleotide fragment containing the UV-induced pyrimidine dimer is not released under nondenaturing in vitro reaction conditions. Also, the uvrABC proteins are stably bound to the incised DNA and do not turn over after the incision event. In this communication it is shown that release of the damaged fragment from the parental uvrABC-incised DNA is dependent upon either chelating conditions or the simultaneous addition of the uvrD gene product (helicase II) and the polA gene product (DNA polymerase I) when polymerization of deoxynucleoside triphosphate substrates is concomitantly catalyzed. The product of this multiprotein-catalyzed series of reactions serves as a substrate for polynucleotide ligase, resulting in the restoration of the integrity of the strands of DNA. The addition of the uvrD protein to the incised DNA-uvrABC complex also results in turnover of the uvrC protein. It is suggested that the repair processes of incision, excision, resynthesis, and ligation are coordinately catalyzed by a complex of proteins in a "repairosome" configuration.     

Complex and simple coronary artery stenoses: a new way to interpret coronary angiograms based on morphologic features of lesions

For many years, atherosclerotic coronary artery lesions have been described by angiographers only in terms of location and degree of narrowing. However, it has become apparent that coronary stenoses generally have distinct morphologic features that can be recognized at angiography and that allow them to be classified as either "simple" or "complex" plaques. Complex plaques are those characterized by ulcerated or ruptured surfaces, subintimal hemorrhage, superimposed partially occluding thrombi, recanalized thrombi, or some combination. Pathologic studies have shown a very high frequency of these lesions at sites of total thrombotic occlusion of coronary arteries. Clinical and angiographic studies have demonstrated a high frequency of such lesions in living patients with both unstable angina and acute myocardial infarction. The presence of complex stenoses has also been found to increase the risk of future myocardial infarction. Plaque morphology thus appears to significantly affect the prognosis of patients with coronary disease and should be carefully evaluated in interpretation of all coronary angiograms.     

Cell-specific ribosomal DNA spacer variability in human urothelial carcinoma cultures

Length variation of a ribosomal DNA "spacer" region in four chromosomally characterized transitional cell carcinoma cultures was analyzed by restriction endonuclease cleavage and Southern blotting. Cell lines with relative karyotypic conservation, such as UM-UC-2 (modal chromosome number 48, four marker chromosomes) demonstrate little change in the genetically regulated pattern of rDNA spacer length polymorphisms (7.6, 6.7 and 6.0 kilobases) which may be found in normal cells. Cell lines with more aberrant karyotypes, such as UM-UC-3 (modal chromosome number 86, 12 marker chromosomes) and UM-UC-4 (modal number 51, ten marker chromosomes) show fewer ribosomal DNA length variants (7.6, 6.7 kilobases for the former, 7.6 kilobases for the latter), consistent with relaxed constraints on the drive for ribosomal gene homogeneity through inter and intrachromosomal exchange. Uncharacterized rDNA length variants of low copy number were observed in cell lines with many marker chromosomes. Analysis of repetitive DNA structure provides an additional criterion for tumor diagnosis and staging, and a characterized series of tumor cell lines may provide a useful system for understanding repetitive DNA evolution.     

The effectiveness of assertive training with elderly psychiatric outpatients

The usefulness of assertive training for elderly psychiatric outpatients was assessed through a quasi-experimental evaluation of a program at a community geriatric facility. Elderly clients are frequently labeled as untreatable and are therefore often denied therapeutic treatment. This study is an example of the potential effectiveness of applying treatment techniques which have been developed with younger populations to a geriatric population. Nineteen clients, aged 50–75, participated in the study, either as participants in the assertion training or as members of a no-treatment control group. The assertion training consisted of 14 semi-weekly sessions, with coaching and feedback provided by the therapists. Assertive behaviors were assessed through self-report, role play and staff ratings of adaptive behaviors of clients. Pre-intervention comparisons between the groups along these dimensions were nonsignificant. However, post-test assessment indicated a significant between group difference in self-reported assertiveness-(t(17)=2.69;p<.05). Dependent t-tests indicated that the experimental group became more assertive (t(9)=2.59;p<.05), but the control group did not. Changes as assessed by role play and staff rating did not reach statistical significance. Results which indicate the potential effectiveness of assertive training with this population are discussed in terms of a specificity conceptualization of assertiveness and implications for assertive training with this population.This paper is based upon their masters' theses.