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Ingvarsson and Hollobaugh (2011) investigated tact- or echoic-to-intraverbal transfer of stimulus control to "wh" questions for three preschool-aged boys with autism. The current study was a systematic replication of this study with an adolescent girl with Down syndrome. A multi-element design was used to compare the effectiveness and efficiency of picture or echoic prompts presented on an iPad or in vivo to teach "wh" questions. All prompt conditions were effective. Conclusions and recommendations for practice are presented.

Understanding aquifer architecture is critical for managing groundwater resources in western Canada. Recent regulations have yielded abundant new gamma-ray well-log data from the principal aquifer in Alberta, the Paleocene Paskapoo Formation. A major obstacle to utilizing this data is the fact that gamma-ray measurements in the shallow subsurface are made through surface casing, which suppresses gamma-ray readings and effectively prohibits stratigraphic characterization. Here we describe and demonstrate a relatively simple and efficient method for normalizing gamma-ray data from stratigraphic horizons that are behind surface casing and apply this method to the Paskapoo Formation in west-central Alberta. The gamma-ray normalization procedure adjusts the cased gamma-ray values so that high and low percentile values of the resulting gamma-ray statistical distribution are equal to those of the non-cased values. The effectiveness of this procedure is demonstrated by comparing the normalized gamma-ray values from cased intervals with those from nearby wells without casing. Good matches between these wells, as well as the transition between normalized curves at the base of cased zones and the gamma-ray curves at the uppermost portion of uncased zones, suggest this methodology is effective for studying the Paskapoo Formation. The normalized curve allows cased and uncased intervals to be correlated, enabling improved stratigraphic characterization and mapping of fluvial sand bodies behind surface casing. This new data provides the framework for better characterization of aquifer dimensions and the derivation of stratigraphic parameters used to constrain hydrogeological models and enhance groundwater recovery. Pour gerer les ressources d'eau souterraine dans l'Ouest canadien, il est essentiel de comprendre l'architecture des aquiferes. De recentes reglementations ont permis d'obtenir de grandes quantites de donnees de diagraphie de puits par carottage au rayonnement gamma sur le principal aquifere de l'Alberta, la Formation de Paskapoo (Paleocene). Un des principaux obstacles a l'utilisation de ces donnees est le fait que les mesures par rayonnement gamma a de faibles profondeurs sous la surface sont effectuees a travers le tubage de surface, ce qui supprime les lectures de rayonnement gamma et empeche une caracterisation stratigraphique efficace. Dans le present article, nous decrivons et demontrons une methode relativement simple et efficace de normalisation des donnees de rayonnement gamma des horizons stratigraphiques qui se trouvent derriere le tubage de surface et nous appliquons cette methode a la Formation de Paskapoo dans le centre-ouest de l'Alberta. La procedure de normalisation du rayonnement gamma ajuste les valeurs 'encaissees'de rayonnement gamma afin que les valeurs percentiles, basses et elevees, de la distribution resultante de rayonnement gamma soient egales a celles des valeurs non'encaissees'. L'efficacite de cette procedure est demontree en comparant les valeurs de rayonnement gamma normalisees des intervalles encaisses a celles provenant de puits avoisinants sans tubage. En raison des bonnes concordances entre ces puits, et la transition entre les courbes normalisees a la base des zones encaissees et les courbes de rayonnement gamma a la partie superieure des zones non encaissees, cette methode serait efficace pour etudier la Formation de Paskapoo. La courbe normalisee permet la correlation des intervalles encaisses et des intervalles non encaisses, ce qui conduit a une amelioration de la caracterisation stratigraphique et de la cartographie des amas de sable fluvial a l'arriere du tubage de surface. Ces nouvelles donnees fournissent le cadre pour une meilleure caracterisation des dimensions des aquiferes et le calcul de parametres stratigraphiques utilises pour contraindre les modeles hydrogeologiques et rehausser la recuperation d'eau souterraine. [Traduit par la Redaction], Introduction The Western Canadian Sedimentary Basin (WCSB) of Alberta, Canada (Fig. 1), is one of the most intensely explored regions in North America, with thousands of new wells being drilled [...]

Conventional and sterically stabilized liposomes derived from phosphatidylcholine or the antitumor agents, hexadecylphosphocholine and octadecyl-(1,1-dimethyl-4-piperidino-4-yl)-phosphate, as bilayer forming constituents, containing bleomycin, were developed and tested. Liposomal encapsulation of bleomycin enhanced strongly the antitumor activity against P388 leukemia and the Lewis lung carcinoma. This effect was clearly dependent on the size and lipid composition of the bleomycin-containing liposomes. The therapeutic effects were nearly equal for liposomal and free bleomycin in the B16 melanoma. The partial replacement of phosphatidylcholine by alkylphospholipids and the inclusion of polyethylene glycol modified lipids for sterical stabilization did not further improve the therapeutic efficacy but increased, in some cases, the toxicity of liposomes. Bleomycin-induced lung injury was not observed if liposomal bleomycin was administered. [ABSTRACT FROM AUTHOR]

A unit wide behavioral programming system for high functioning mentally retarded clients who displayed maladaptive behavioral excesses was developed and implemented on a coeducational institutional living unit for 7 months. Significant clinical reductions were achieved in client injuries, broken windows, emergency, restraint usage, the percent of clients receiving psychotropic medications and medication dosages. These reductions continued during the program’s maintenance phase. A number of factors are discussed that appear to have contributed to the program’s success. [ABSTRACT FROM AUTHOR]

The article focuses on the treatment of the sexually deviant behavior of mentally retarded individuals. The aversive imagery conditioning was conducted in a darkened room with the client relaxing on a couch in order to facilitate the imagery process. The treatment consisted of pairing painful faradic shock with the imagined and/or actual act of exhibitionism.

Calcium excretion and deposition were studied during sporogenesis in the myxomycete, Physarella oblonga. Prior to fruiting, the migrating vegetative plasmodium contains numerous, large channels connected to the external environment. During early sporangial development, these channels become smaller and are isolated as channel remnants. Plasmodial microfilament bundles also disappear at this time. Internally, two types of spheres, each about 0.5-1.5 μm in diameter, are formed in the channel remnants. A dense sphere appears to originate from small particles initially secreted from the mitochondria. These particles then enter the channels and channel remnants by reverse pinocytosis and fuse to form the dense spheres. A second, less dense sphere has no detectable cytoplasmic origin but also appears to form in the channels and channel remnants. Both types of spheres are concentrated by the fusion of channel remnants to form enlarged regions (knots and spikes) of the developing capillitium. Some of the channel remnants also fuse with the outer surface of the sporangium, depositing both spheres to the outside. Both spheres have been studied by various light and electron microscopic techniques and with specific histochemical and analytical procedures. The less dense spheres appear to contain a major portion of calcium in the form of calcium carbonate. These results are compared to other recent studies on calcium deposition in the Myxomycetes and a different mechanism for calcium deposition is proposed. [ABSTRACT FROM AUTHOR]

Investigates the induction of hypertriglyceridemia. Use of rats as animal model; Feeding regimens with and without 13-cis-retinoic acid; Levels of Triglyceride and arachidonic acid.

Hodgkin's and Reed/Sternberg (HRS) cells, the tumour cells in classical Hodgkin's lymphoma (HL), represent transformed B cells in nearly all cases. The detection of destructive somatic mutations in the rearranged immunoglobulin (Ig) genes of HRS cells in classical HL indicated that they originate from preapoptotic germinal centre (GC) B cells that lost the capacity to express a high-affinity B-cell receptor (BCR). Several aberrantly activated signalling pathways and transcription factors have been identified that contribute to the rescue of HRS cells from apoptosis. Among the deregulated signalling pathways, activation of multiple receptor tyrosine kinases in HRS cells appears to be a specific feature of HL. In about 40% of cases of classical HL the HRS cells are infected by Epstein-Barr virus (EBV), indicating an important role of EBV in HL pathogenesis. Interestingly, nearly all cases of HL with destructive Ig gene mutations eliminating BCR expression (e.g. nonsense mutations) are EBV-positive, suggesting that EBV-encoded genes have a particular function to prevent apoptosis of HRS-cell precursors that acquired such crippling mutations. This idea is further supported by the recent demonstration that isolated human GC B cells harbouring crippled Ig genes can be rescued by EBV from cell death, giving rise to lymphoblastoid cell lines. The molecular analysis of composite Hodgkin's and non-Hodgkin's lymphomas indicated that many cases develop from a common GC B-cell precursor in a multistep transformation process with both shared and distinct oncogenic events., (Copyright (c) 2005 Wiley-Liss, Inc.)

In classic Hodgkin lymphoma (HL) and posttransplantation lymphoproliferative disease (PTLD), 2 malignancies frequently associated with Epstein-Barr virus (EBV), the tumor cells often appear to derive from B-cell receptor (BCR)-deficient and therefore preapoptotic germinal center (GC) B cells. To test whether EBV can rescue BCR-less GC B cells, we infected human tonsillar CD77+ GC B cells in vitro with EBV. More than 60 monoclonal lymphoblastoid cell lines (LCLs) were established. Among these, 28 cell lines did not express surface immunoglobulin (sIg). Two of the sIg-negative cell lines carry obviously destructive mutations that have been introduced into originally functional V(H) gene rearrangements during the process of somatic hypermutation. Quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) showed that in most other lines the sIg deficiency was not simply the result of transcriptional down-regulation, but it was rather due to posttranscriptional defects. These findings strongly support the idea that EBV plays a central role in the pathogenesis of classic HL and PTLD by rescuing BCR-deficient, preapoptotic GC B cells from apoptosis, and that EBV infection renders the cells independent from survival signals normally supplied by a BCR. The monoclonal LCLs represent valuable models for early stages of lymphoma development in classic HL and PTLD.

Primary lymphomas of the central nervous system (PCNSLs) were investigated for their capacity to perform further maturation steps. We studied a series of 11 PCNSLs derived from immunocompetent patients for immunoglobulin (Ig) class switch recombination (CSR) by performing reverse transcriptase-polymerase chain reaction (RT-PCR) for transcripts of Ig constant region gene segments (IGHC). This analysis revealed exclusive transcription of IgM and IgD mRNA in the absence of IgG, IgA, or IgE transcription. This finding was corroborated at the protein level by the immunohistochemical demonstration of IgM on the surface of the tumor cells. The unexpected lack of CSR may be due to internal switch mu region deletions, which were detected in 7 of 11 cases. We also found that expression of activation-induced cytidine deaminase (AID), which is required for CSR and somatic hypermutation, was detectable by RT-PCR in 4 of 10 cases and by immunohistochemistry in one of three cases analyzed. This may indicate that ongoing somatic mutation, which is often observed in PCNSL, could be due to sustained AID expression in a fraction of cases and that intraclonal V gene diversity may occur in other cases at an earlier phase of tumor clone expansion, when AID may have been expressed.

It is well known that caloric restriction inhibits, whereas excess calories promote, mammary tumorigenesis in rats. However, the relative contribution to carcinogenesis by calories derived from fat or from carbohydrate are not well established. To determine the relative effects of calories from fat or from carbohydrate, as well as any interaction of dietary fiber on the promotion of 7,12-dimethylbenz[a]anthracene-induced mammary tumors, we fed isocalorically nine diets containing different ratios of fat, carbohydrate, and fiber to female Sprague-Dawley rats treated with 7,12-dimethylbenz[a]anthracene (30/group). Under conditions of isocaloric consumption, at or near ad libitum feeding, calories from dietary fat had approximately twofold greater promoting effect on final body weight and tumor incidence than calories derived from dietary carbohydrate. Dietary fiber had an inhibitory effect on tumor development, but the effect was evident only in the high-fat groups. Logistic regression analysis of tumor incidence gave beta-coefficient estimates for the relative effects of fat, carbohydrate, and fiber of 0.866, 0.189, and -4.281, respectively. Time-to-tumor analysis by the Weibull model indicated beta-estimates of 3.016, 3.324, and 5.825 for dietary fat, carbohydrate, and fiber, respectively, indicating that fat shortens and fiber increases the length of time to tumor. The statistical model derived from these results also indicates a significant synergistic interaction of dietary fat and carbohydrate on final body weight and tumor incidence.

Allylisothiocyanate (AITC) has been evaluated for its ability to initiate unscheduled DNA synthesis (UDS) in the livers of male rats in vivo. Specific Pathogen Free outbred albino Hsd/Ola Sprague-Dawley rats were exposed by oral gavage to 37.5 or 125 mg/kg AITC in corn oil and hepatocytes assessed for UDS by autoradiography 2 and 14 h later. AITC did not induce UDS at either dose level at either time point. These data are consistent with all other evidence indicating that AITC does not act as a genotoxin in vivo, despite positive response in some in vitro screening assays. The reported occurrence of benign bladder papillomas in male rats but not female rats or mice of either sex is consistent with non-genotoxic action and may be attributed to chronic irritation of the bladder epithelium by AITC and its cysteine conjugate metabolite excreted by male rats in unusually concentrated form. It is concluded that the weight of evidence is insufficient to regard AITC as a genotoxin capable of human carcinogenicity.

The cytotoxic response to aflatoxin B(1) (AFB) was investigated in RTL-W1, a cell line derived from the normal liver of a mature rainbow trout (Oncorhynchus mykiss). AFB altered RTL-W1 morphology and ultrastructure and inhibited DNA synthesis. The effective concentration required for 50% inhibition (EC(50)) of DNA synthesis, after 2 days of treatment was 0.04 mug/ml. This response was compared with that of two other salmonid, but non-liver, cell lines [rainbow trout gonad (RTG-2) and Chinook salmon embryo (CHSE-214)]. Although RTG-2 cells were as sensitive as RTL-W1 cells (EC(50) for inhibition of DNA synthesis was 0.05 mug/ml), CHSE-214 cells were unresponsive to AFB at concentrations as high as 2 mug/ml. After a single AFB exposure, RTL-W1 sublines were isolated that had phenotypic changes typical of malignant transformation. These were increased growth rate, reduced contact inhibition of growth, altered cellular morphology and growth in soft agar. In addition, RTL-W1 metabolized AFB: the major metabolites, aflatoxin (AFL) and aflatoxin M(1) (AFM), were detected by thin-layer chromatography and HPLC. The relative amounts of these metabolites, unlike those observed with RTG-2 cells, were in close agreement with those produced by trout liver in vivo. Thus, RTL-W1 could provide a sensitive in vitro model system for studying the action of biotransformation requiring xenobiotics. Overall, the observed responses were similar to those reported for liver cells in AFB-exposed trout, suggesting that RTL-W1 cells are suitable for studying cytotoxic effects and malignant transformation in vitro.

In a previous study (Cancer Res 51, 907, 1991) in which we found an inverse relationship between quantity of dietary corn oil and saturated fat, in a constant 15% fat diet, on the tumor promotion stage of skin carcinogenesis, it was not clear whether one or both types of fat played a modulatory role. The purpose of the present study therefore was to compare the effect of 1) increasing corn oil in corn oil-only diets and 2) increasing saturated fat, with a constant level of 5% corn oil, on tumor promotion. In the first study, the effects of five levels of dietary corn oil (5%, 10%, 15%, 20%, and 25%) on the incidence and rat of papilloma and carcinoma development were determined in female Sencar mice fed these diets one week after initiation with 7,12-dimethylbenz[a]anthracene and three weeks before the start of promotion with 12-O-tetradecanoylphorbol-13-acetate. A papilloma incidence of 100% was reached first in the 5% corn oil group, at 10 weeks, followed by the 10% group at 13 weeks and the 15% and 20% group at 16 weeks. The highest corn oil group achieved a 90% incidence. There were marked differences in latency of carcinoma development among the diet groups. At Week 29, the cumulative carcinoma incidence was 56% and 32%, respectively, in the 5% and 10% corn oil groups, whereas the incidence in the two highest corn oil (20% and 25%) groups was only 8% and 4%, respectively. In the second study, the effects of diets containing 5% corn oil and increasing levels of coconut oil (5%, 10%, 15%, and 20%) on the incidence and rat of papilloma and carcinoma development were determined, as described above. No significant difference in latency or incidence of papillomas or carcinomas was noted among these saturated fat diet groups. It thus appears that higher levels of dietary corn oil are associated with a reduced cancer incidence in this model system.

A cell line, RTL-W1, has been developed from the normal liver of an adult rainbow trout by proteolytic dissociation of liver fragments. RTL-W1 can be grown routinely in the basal medium, L-15, supplemented with 5% fetal bovine serum. In this medium, the cells have been passaged approximately 100 times over an 8-year period. The cells do not form colonies or grow in soft agar. The cultures are heteroploid. The cell shape was predominantly polygonal or epithelial-like, but as cultures became confluent, bipolar or fibroblast-like cells appeared. Among the prominent ultrastructural features of RTL-W1 were distended endoplasmic reticulum and desmosomes. Benzo[a]pyrene was cytotoxic to RTL-W1. Activity for the enzyme, 7-ethoxyresorufin O-deethylase (EROD), which is a measure of the cytochrome P4501A1 protein, increased dramatically in RTL-W1 upon their exposure to increasing concentrations of either beta-naphthoflavone (BNF) or 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). With these properties, RTL-W1 should be useful for studying the expression of the cytochrome P450 enzymes and as a tool for assessing the toxic potency of environmental contaminants.

On the basis of reports of rat mammary- and pancreas-tumor models, we hypothesized that an increase in consumption of linoleic acid (LA) would also cause an enhancement in mouse skin-tumor promotion. SEN-CAR mice were placed on diets containing 0.8%, 2.2%, 3.5%, 4.5%, 5.6%, 7.0%, or 8.4% LA, 1 week after initiation with 7,12-dimethylbenz(a)anthracene and 3 weeks before starting promotion with 12-O-tetradecanoylphorbol-13-acetate. An inverse correlation (r = -0.92) was observed between papilloma number and level of LA; however, there was little difference in tumor incidence. A relationship between diet and carcinoma incidence was also found. The fatty acid composition of epidermal phospholipids reflected the dietary LA levels. 12-O-Tetradecanoylphorbol-13-acetate-induced epidermal prostaglandin E2 levels generally decreased with increasing dietary LA. To determine whether this inverse correlation between dietary LA and tumor yield was due to species differences or organ-model differences, a mammary carcinogenesis experiment was performed. SENCAR mice were fed the 0.8%, 4.5%, and 8.4% LA diets. All mice received 6 mg 7,12-dimethylbenz(a)anthracene, administered intragastrically at 1 mg/week. Tumor appearance was delayed in the 0.8% LA diet group, and a positive dose-response relationship between dietary LA and mammary-tumor incidence was observed. These studies suggest that the effect of dietary LA on tumor development is target tissue specific rather than species specific.

We recently reported (J. Leyton et al., Cancer Res., 51: 907-915, 1991) an inverse correlation between skin tumor number and level of dietary linoleic acid (LA) in SENCAR mice following an initiation-promotion protocol. These results differed from the reported (C. Ip et al., Cancer Res., 45: 1997-2001, 1985) positive correlation between dietary LA and tumor incidence for the rat mammary gland. The goal of the study reported here was to determine whether this dissimilarity was due to organ site or species differences. Female SENCAR mice were fed 1 of 3 15% fat diets containing LA at levels of 0.8, 4.5, and 8.4% before, during, and after intragastric administration of 6 mg (1 mg/week) 7,12-dimethylbenz(a)anthracene. A positive correlation between level of dietary LA and mammary tumor incidence was observed such that for the first 15 weeks, the incidence was greatest in the 8.4% LA diet group, followed by the 4.5% and then the 0.8% LA groups. Distinct dietary effects on latency were also noted in that 15, 12, and 8 weeks after cessation of 7,12-dimethylbenz(a)anthracene were required for a 40% carcinoma incidence in the 0.8, 4.5, and 8.4% LA diet groups, respectively. A histopathological analysis of all tumors revealed that the predominant type was the adenosquamous carcinoma, which comprised 46.6, 54.1, and 77.7% of all mammary tumors for diets containing 0.8, 4.5, and 8.4% LA, respectively. The second most common tumor was the adenocarcinoma type B, which was found with a frequency of 33% in the 0.8% and 4.5% LA diet groups and 22% in the 8.4% LA diet group. These results indicate that SENCAR mice have a short latency period for 7,12-dimethylbenz(a)anthracene-induced mammary tumor development and that rat and mouse mammary tumor development is modified by dietary LA in a similar manner, although in the SENCAR mouse dietary LA did not have a saturating effect. In addition, high dietary LA was found to be associated specifically with an increased incidence of adenosquamous carcinomas but not of other types of mammary tumors.

Based on the biological activity of arachidonic acid metabolites, we hypothesized that alterations in the consumption of linoleic acid, the precursor to arachidonic acid, would result in a modification in tumor development when fed during the tumor promotion stage of the mouse skin initiation-promotion model. The effects of seven different levels of dietary linoleic acid (LA), supplied as corn oil in a 15% fat diet, on the incidence and rate of papilloma and carcinoma development were determined. SENCAR mice were placed on one of the experimental diets, containing 1.0, 3.6, 6.0, 7.9, 9.9, 12.5, or 15.0% corn oil, 1 week after initiation with 10 nmol of 7,12-dimethylbenz(a)anthracene and 3 weeks prior to the start of twice weekly promotion with 1 micrograms 12-O-tetradecanoylphorbol-13-acetate (TPA). At 15 weeks of TPA treatment there were significant differences in papilloma number among diet groups, such that an inverse correlation (r = 0.92) was observed between tumor number and level of corn oil; the lowest corn oil diet group had an average of 11.7 tumors/mouse, while the highest corn oil group had 5.4 tumors/mouse. However, there was little difference in tumor incidence among diet groups. A general relationship between diet and carcinoma incidence was also found, such that the highest corn oil diet group had the lowest carcinoma incidence. In an experiment performed with DBA/2 mice, the average number of papillomas/mouse at 17 weeks was 4.5 (1.0% corn oil), 5.6 (7.9%) corn oil), and 2.3 (15.0% corn oil). Papilloma incidence was also affected by diet, with a 79% incidence for the 15.0% corn oil and an incidence of 93% for the 1.0% corn oil group. analyses of the fatty acid composition of epidermal phospholipids in mice fed the experimental diets reflected the dietary LA levels, in that an accumulation of phospholipid LA, accompanied by an overall decrease in arachidonic acid, occurred with increasing dietary corn oil. In spite of the high membrane levels of LA, no measurable amount of epidermal conjugated dienes of LA could be detected. Epidermal prostaglandin E2 levels in acetone-treated mice were similar for all diet groups (approximately 3 pg/micrograms DNA). However, 6 h after topical application with 4 micrograms of TPA, prostaglandin E2 levels were elevated 5- to 10-fold; an inverse correlation (P less than 0.05) was seen with increasing dietary LA, although the concordance with decreased phospholipid arachidonic acid was not strong.(ABSTRACT TRUNCATED AT 400 WORDS)

Transmission electron micrographs of glutaraldehyde- OsO(4)-fixed Rhizobium trifolii 0403 before and after cells were treated with 16.6 mM succinate showed that treated cells increased in mass by increasing cytoplasmic volume. The morphology of succinate-treated cells was identical to that of bacteroids, and the appearances of the envelope and periplasmic space were similar. The primary difference was in inclusion number and type.

An analysis of hepatic aflatoxin B1-DNA adduct (HADA) concentrations in rats and trout demonstrated that the hepatic cancer risk was linearly and quantitatively related in both species. Additionally, the adduct-risk correlation for short-term exposure accurately predicted chronic exposure risk in trout. Although rat and trout liver cells differ substantially in their nuclear DNA content, they appeared to experience similar cancer risks at a given HADA concentration. This may indicate that the liver nuclei of both species contain a similar number of an equivalent protooncogene(s). This analysis also provided a possible basis for the use of adduct measurements for estimating human cancer risk. The minimum human virtual safe dose for aflatoxin was estimated to be 0.264 ng/kg/day on the basis of this approach.

This report relates the postoperative clinical and cineangiographic status of 67 patients selected from a total of 202 patients who underwent coronary artery surgery at the Peter Bent Brigham Hospital from July, 1970, to July, 1972. The mean interval after operation was 12.6 months. Ninety-one per cent of the 67 patients were improved from their preoperative status. Forty-eight patients (71 per cent) were studied to evaluate recurrence of mild to moderate angina or occurrence of interval myocardial infarction, and 19 patients (29 per cent) were entirely asymptomatic. In the 67 patients studied, 112 coronary arteries received a total of 115 grafts. (There were 89 ungrafted coronary arteries.) Total graft patency rate for the 58 patients in whom angina was totally or significantly relieved was 65 per cent. However, one or more grafts were patent in 52 (90 per cent) of these 58 patients. In grafted arteries, progression was found in segments proximal to the graft in 37 per cent of arteries, at the site of anastomosis in 10 per cent, and distal to the site of anastomosis in 17 per cent. The frequency of obstruction distal to the site of anastomosis was not significantly different from the frequency of progression in nongrafted arteries, in contrast to preliminary data from this laboratory. Overall and regional progression in grafted arteries appeared to occur primarily within the first four months after surgery and was found, thereafter, in a constand percentage of vessels studied. Progression in coronary arteries was independent of patency or occlusion of the graft to the vessel. It is hypothesized that while proximal progression is probably a consequence of altered hydraulic factors, distal lesions seem to represent natural progression of atherosclerotic disease.

In order to determine the effect of direct bypass surgery on the total coronary arterial supply to the heart, a numerical construct was devised to incorporate the development of new obstructive lesions and the presence of patent or nonpatent grafts. This construct, termed a vascularization index (VI), was used to evaluate left ventricular function and anginal symptoms after coronary artery bypass surgery in 56 patients. Patients with an increase in local or total arterial blood supply (positive delts VI) often had similar directional changes in segmental wall motion and ventricular ejection fraction. Patients with a decrease in local or total arterial blood supply (negative delta VI), due to either nonpatent grafts or progression of atherosclerotic disease, also usually had similar directional changes in segmental wall motion and ventricular ejection fraction. (Although nearly all patients reported a decrease in anginal symptoms after surgery, delta VI could not identify degree of improvement.) Use of an integrated approach in describing pre and postoperative myocardial blood supply appears to be the most reliable method of explaining changes in left ventricular function.

A comprehensive ultrastructural analysis of sporulation and parasporal crystal development is described for Bacillus thuringiensis. The insecticidal crystal of B. thuringiensis is initiated at the start of engulfment and is nearly complete by the time the exosporium forms. The crystal and a heretofore unobserved ovoid inclusion develop without any clear association with the forespore septum, exosporium, or mesosomes. These observations contradict previous hypotheses that the crystal is synthesized on the forespore membrane, exosporium, or mesosomes. Formation of forespore septa involves densely staining, double-membrane-bound, vesicular mesosomes that have a bridged appearance. Forespore engulfment is subpolar and also involves mesosomes. Upon completion of engulfment and the following cytoplasmic changes occur: decrease in electron density of the incipient forespore membrane; loss of bridged appearance of incipient forespore membrane; change in stainability of incipient forespore, forespore, and mother cell cytoplasms; and alteration in staining quality of plasma membrane. These changes are involved in the conversion of the incipient forespore into a forespore and reflect "commitment" to sporulation.

Left ventricular function and motion in 12 adults with an ostium secundum atrial septal defect were analyzed utilizing biplane cineangiography. Values for left ventricular end-diastolic volume index, stroke volume index, ejection fraction, left ventricular end-diastolic pressure and mean rate of circumferential fiber shortening were compared with values in an age-matched group of 11 normal subjects. Comparisons of ventriculographic and echocardiographic data were also made in 5 patients and 10 control subjects. Cardiac index was smaller in patients than in the normal subjects (3.6 vs. 4.5 liters/min per m2, P less than 0.01). Although left ventricular end-diastolic pressure was similar (8 mm Hg in both groups), the end-diastolic volume index was significantly smaller in patients than in normal subjects (56 vs. 76 ml/m2, P less than 0.05). Stroke volume index was also significantly smaller in patients (40 vs. 52 ml/m2, P less than 0.01). The two groups had similar values for ejection fraction (65 +/- 2 percent [standard error of the mean] in patients vs. 68 +/- 2 percent in normal subjects), circumferential fiber shortening velocity (1.67 +/- 0.13 vs. 1.81 +/- 0.15 circumferences/sec.), heart rate (91 +/- 7 vs. 90 +/- 5 beats/min) and mean systemic arterial pressure (92 +/- 5 vs. 87 +/- 3 mm Hg). Early systolic bulging of the upper ventricular septum toward the right ventricle was seen in 10 of 12 patients with an atrial septal defect but in no normal subject. Echocardiographic data supported these findings. No other abnormalities of motion were consistently noted. It is concluded that the left ventricle of patients with an atrial septal defect is subnormal in volume and abnormal in sequence of contraction of the septum and is characterized by apparent decreased distensibility.

The ability to predict reversibility of ventricular dysfunction should be important in determining operability. This study examined the usefulness of postextrasystolic potentiation as such a predictor. Left ventricular wall motion was studied using cineventriculography in 31 patients before and after revascularization surgery. Preoperative ejection fraction and wall motion were analyzed during a sinus beat and after a random ventricular extrasystole, whereas postoperative ejection fraction and wall motion were examined only during a sinus beat. Changes in ventricular motion were correlated with changes in vascular supply achieved by operation. Of the 7 patients whose ejection fraction was improved postoperatively, 6 had shown postextrasystolic potentiation compared with only 10 of the 24 patients without such improvement (P less than 0.05). Regional wall motion analysis also showed a significant association between postextrasystolic potentiation and postoperative improvement in wall motion. Of 26 zones judged to have an increased vascular supply after operation, 11 showed increased motion postoperatively. All 11 had shown postextrasystolic potentiation, compared with only 5 of 15 zones with increased vascular supply but without increased postoperative motion (P less than 0.001). Thus, postextrasystolic potentiation seems to be a useful predictor of the ability of asynergic myocardium to respond to successful revascularization surgery.

MMPI profiles of female adolescents hospitalized on a general pediatrics floor following a suicide attempt were compared to a control group of medically hospitalized, female adolescents referred for psychiatric evaluation. The suicide attempters had only a lower score on the K scale when compared to the control group. Results do not suggest that a single MMPI profile differentiates suicide attempters from a comparison group of adolescents with emotional difficulties. Implications of these findings are discussed.