Duplex scanning alone is not sufficient imaging before secondary procedures after lower extremity reversed vein bypass graft

PURPOSE: Duplex surveillance of lower extremity reversed vein bypass grafts (LERVG) is a means of identifying patients at risk for occlusion. The perceived accuracy of duplex scan as a means of identifying stenoses has led many surgeons to perform graft revision on the basis of duplex scan alone. This may result in missing additional lesions that are threatening patency. To assess the role of duplex scan as the sole imaging method before revision of LERVGs, we reviewed consecutive patients undergoing revisions who underwent preoperative arteriography after identification of duplex scan abnormalities. METHODS: Duplex scan results, operative reports, and preoperative arteriograms for patients undergoing LERVG revision from January 1990 to December 1997 were reviewed. A standard duplex scan surveillance protocol was followed, and attempts were made to survey the entire graft, including inflow and outflow. Duplex scan results were compared with the results of preoperative arteriograms and the operation performed to determine if all significant lesions were identified by means of duplex scan alone. RESULTS: Two hundred five LERVG revisions were performed. The 5-year assisted primary patency rate was 91%. In 119 cases (58%), arteriography did not contribute significantly to duplex scan findings. Arteriography significantly contributed to operative planning in 86 cases (42%). In 38 cases (19%), only a low-flow state was identified by means of duplex scan, and a correctable stenosis was identified by means of arteriography. In 48 cases (23%), additional significant lesions corrected at operation were identified by means of arteriography. These included 26 inflow, 16 graft, and 8 outflow lesions. Arteriography was most useful as a means of determining the revision procedure performed when there were inflow lesions (P <.05) or when the proximal anastomosis was to the profunda or superficial femoral arteries (P <.05). All frequently performed bypass graft configurations had some discrepancy between arteriographic and duplex scan findings. CONCLUSION: Available data do not permit prediction of which LERVG are immune from missed lesions in a duplex scan surveillance protocol. This suggests to us that arteriography is mandatory before LERVG revisions.     

Iterated sequence databank search methods.

Iterated sequence databank search methods were assessed from the viewpoint of someone with the sequence of a novel gene product wishing to find distant relatives to their protein and, with the specific searches against the PDB, also hoping to find a relative of known structure. We examined three methods in detail, spanning a range from simple pattern-matching to sophisticated weighted profiles. Rather than apply these methods 'blindly' (with default parameters) to a large number of test queries, we have concentrated on the globins, so allowing a more detailed investigation of each method on different data subsets with different parameter settings. Despite their widespread use, regular-expression matching proved to be very limited-seldom extending beyond the sub-family from which the pattern was derived. To attain any generality, the patterns had to be 'stripped-down' to include only the most highly conserved parts. The QUEST program avoided these problems by introducing a more flexible (weighted) matching. On the PDB sequences this was highly effective, missing only a few globins with probes based on each sub-family or even a single representative from each sub-family. In addition, very few false-positives were encountered, and those that did match, often only did so for a few cycles before being lost again. On the larger sequence collection, however, QUEST encountered problems with maintaining (or achieving) the alignment of the full globin family. psi-BLAST also recognised almost all the globins when matching against the PDB sequences, typically, missing three or four of the most distantly related sequences while picking-up a few false-positives. In contrast to QUEST, psi-BLAST performed very well on the larger databank, getting almost a full collection of globins although still retaining the same proportion of false-positives. SAM applied to the PDB sequences performed reasonably well with the myoglobin and hemoglobin families as probes, missing, typically several of the more difficult proteins but performed poorly with the leghemoglobin probe. Only with the full family range as a probe did it produce results comparable to psi-BLAST and QUEST. With the larger databank, SAM produced a good result but, again, this was only achieved using the full range of sequence variation with the default regulariser and use of Dirichlet mixtures completely failed in this situation.     

Improving grid behaviour

In this paper, the author describes how the inglorious Summer-of-1996 blackouts taught the Western USA to improve emergency grid control and protection and to sharpen power network simulation techniques     

Cancer occurrence in the elderly: agreement between three major data sources

OBJECTIVE: To identify the individual, dyad, and family variables that influence young women's perceptions of risk for sexually transmitted diseases (STDs), including human immunodeficiency virus (HIV). DESIGN: Cross-sectional telephone survey using forced-choice questioning. Data were analyzed using first-order correlations and logistic regression. SETTING: Participants were recruited from a mid-Atlantic study of young adults and from volunteers at a mid-Atlantic university and surrounding community. PARTICIPANTS: A convenience sample of 93 sexually active, unmarried, heterosexual women, ages 17-26 years. The majority of the study sample was white. MAIN OUTCOME MEASURE: Respondents were asked to estimate their own level of risk for STDs, including HIV, using the responses no, low, moderate, and high risk. Responses were later recoded into no risk versus some risk. RESULTS: Communication with parents about sexual risk decreased the odds that women would see themselves as being at no risk. Consistent condom use, relationship satisfaction, and perceiving the partner as no risk increased the odds that women would believe they were at no risk. CONCLUSIONS: Nurses can incorporate these and other study findings into the design of sexual risk reduction programs. Programs that enhance parent-teen communication about sexual risks and assist young women to examine their perceptions of their partners may be more effective than programs that provide information only.     

Assessment of quality of cod roes and relationship between quality and maturity stage

Cod roe landings are subject to great variability regarding their quality and subsequent price for the food industry. A scheme was developed for the classification of cod roe into four quality grades (A, B, C and D) based on appearance and texture attributes as described by cod roe traders. Evaluation of the maturity stage of 80 commercial cod ovaries through the frequency distribution of oocyte diameter and the percentage presence of empty follicular sacks revealed that cod ovaries with commercial value are at stage 4 (ripe or vitellogenic), stage 5 (spawning) and stage 6 (spent) of development. The designated maturity stages were found to be closely related to the described quality grades. This relationship implied that vitellogenic ovaries (stages 4a, 4b and 4c) were of A quality, early spawning ovaries (stage 5a) were most often classed as B quality, advanced and late spawning ovaries (stage 5b and 5c) were of C quality, whilst spent ovaries (stage 6) were of the lowest quality grade (D). Several physicochemical characteristics recorded (eg pH, membrane features) were also found to be related to the quality and the maturity stage of the ovaries. There is a significant relationship between roe quality and moisture content, with roes of higher quality having a lower moisture content. © 1999 Society of Chemical Industry     

Effect of thyrotropin-releasing hormone on secretion of thyrotropin, prolactin, thyroxine, and triiodothyronine in pregnant and fetal rhesus monkeys

The effect of thyrotropin-releasing hormone (TRH) on the pituitary-thyroid axis and on prolactin secretion was studied in pregnant Rhesus monkeys during the latter period of gestation and in non-pregnant female controls. The baseline plasma concentrations of TSH, T3, T4, and prolactin (PRL) of pregnant monkeys did not differ from those of non-pregnant monkeys. After administration of TRH, plasma prolactin rose to higher levels in pregnant monkeys than in non-pregnant monkeys whereas there was a similar response of plasma TSH, T4 and T3 in both groups. The baseline plasma TSH was elevated and plasma T3 was decreased in the fetus compared with the mother. Administration of TRH iv to the maternal monkey caused a larger response in the fetal plasma TSH than in that of the mother and was followed by larger increments in plasma T4 and T3 concentrations in the fetuses than in the mothers. The larger increments of plasma TSH and thyroid hormones in the fetus compared with the mother also occurred when TRH was given iv to the fetus. There was a significant rise of plasma prolactin in both mother and fetus after administration of TRH to mother or fetus; the increase of plasma PRL was much higher in the mother than in the fetus. The data show that TRH can cross the primate placenta in either the maternal to fetal or fetal to maternal direction. The fetal thyroid of the Rhesus monkey during the latter period of gestation can release both T4 and T3 in response to TSH.     

Territorial cognition: Assessing Altman's typology.

The empirical validity of I. Altman's (1975) typology of human territories was assessed using a modified Role Construct Repertory Grid. Urban and suburban Ss, matched on several variables, were interviewed in their homes. It was expected that suburban Ss, as compared to urban Ss, would perceive more control over secondary and public territories. Results confirm the validity of Altman's typology and the importance of the dimensions of centrality and temporal duration. The expected urban vs suburban differences were obtained. Results also indicate that primary and secondary territories, by providing the setting for interaction at varying levels of formality and exclusion, possessed role-structuring properties. Future research on human territoriality should take a multimethod approach and explore the covariation of territorial cognitions and behaviors. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Dream patterns in Anglo and Chicano young adults

This study is the conclusion of an exploratory cross-cultural investigation of dream content and organization. Following our report in "Ego Modalities in the Manifest Dreams of Male and Female Chicanos," (Brenneis and Roll, 1975), this paper examines differences in the organization and content of dreams: (1) between Anglo men and women; (2) between Anglo and Chicano men and Anglo and Chicano women; and (3) between Anglos and Chicanos.