Measles-induced encephalitis

Encephalitis is the most frequent neurological complication of measles virus infection. This review examines the pathophysiology of measles infection and the presentations, diagnosis and treatment of the four types of measles-induced encephalitis including primary measles encephalitis, acute post-measles encephalitis, measles inclusion body encephalitis and subacute sclerosing panencephalitis. The early symptoms of encephalitis may be non-specific and can be mistakenly attributed to a systemic infection leading to a delay in diagnosis. This review provides a summary of the symptoms that should cause health care workers to suspect measles-induced encephalitis.

The view from the road: the contribution of on-road glance-monitoring technologies to understanding driver behavior

Using glance-monitoring technologies for on-road studies is an excellent way to investigate driver behaviors in an ecologically valid setting. Recent advances in glance-monitoring technologies have made it possible to conduct on-road studies of drivers' glance behavior that heretofore were simply not possible. Yet it is not always easy to determine which glance-monitoring technology to use for a particular application. Here, we first identify the generic capabilities of the various glance-monitoring technologies. We then describe how particular glance-monitoring technologies have been used in the field to (a) identify the skill deficiencies of novice and older drivers, (b) evaluate the effectiveness of training programs that are designed to reduce deficits in these skills, and (c) address interface issues both inside (e.g., collision warning systems) and outside (e.g., yield markings) the vehicle. The limitations and advantages of on-road eye-tracking and the associated glance-monitoring technologies are identified throughout. A comparison, where possible, is made between the results of on-road eye-tracking studies of drivers' behaviors and the results of those studies conducted in the laboratory. Overall, the use of appropriate on-road glance-monitoring technologies has greatly enhanced our theoretical understanding of why drivers behave the way they do, and this knowledge has paved the way for significant improvements in road user safety.

Evaluation of different speech and touch interfaces to in-vehicle music retrieval systems

In-vehicle music retrieval systems are becoming more and more popular. Previous studies have shown that they pose a real hazard to drivers when the interface is a tactile one which requires multiple entries and a combination of manual control and visual feedback. Voice interfaces exist as an alternative. Such interfaces can require either multiple or single conversational turns. In this study, each of 17 participants between the ages of 18 and 30 years old was asked to use three different music retrieval systems (one with a multiple entry touch interface, the iPod, one with a multiple turn voice interface, interface B, and one with a single turn voice interface, interface C) while driving through a virtual world. Measures of secondary task performance, eye behavior, vehicle control, and workload were recorded. When compared with the touch interface, the voice interfaces reduced the total time drivers spent with their eyes off the forward roadway, especially in prolonged glances, as well as both the total number of glances away from the forward roadway and the perceived workload. Furthermore, when compared with driving without a secondary task, both voice interfaces did not significantly impact hazard anticipation, the frequency of long glances away from the forward roadway, or vehicle control. The multiple turn voice interface (B) significantly increased both the time it took drivers to complete the task and the workload. The implications for interface design and safety are discussed.

Can younger drivers be trained to scan for information that will reduce their risk in roadway traffic scenarios that are hard to identify as hazardous?

Younger drivers (18-21 years) are over-involved in crashes. Research suggests that one of the reasons for this over-involvement is their failure to scan areas of the roadway for information about potential risks in situations that are hazardous, but not obviously so. The primary objective of the present study is to develop and evaluate a training program that addresses this failure. It was hypothesised that PC-based hazard anticipation training would increase the likelihood that younger drivers would scan for potential hazards on the open road. In order to test this hypothesis, 12 trained and 12 untrained drivers' eye movements were measured as they drove a vehicle on local residential, feeder and arterial roads. Overall, the trained drivers were significantly more likely to gaze at areas of the roadway that contained information relevant to the reduction of risks (64.4%) than were the untrained drivers (37.4%). Significant training effects were observed even in situations on the road that were quite different from those shown in training. These findings have clear implications for the type of training of teen drivers that is necessary in order to increase their anticipation of hazards.

Integrating patient satisfaction into performance measurement to meet improvement challenges

BACKGROUND

A Value Compass has been proposed to guide health care data collection. The "compass corners" represent the four types of data needed to meet health care customer expectations: appropriate clinical outcomes, improved functional status, patient satisfaction, and appropriate costs. Collection of all four types of data is necessary to select processes in need of improvement, guide improvement teams, and monitor the success of improvement efforts. INTEGRATED DATA AT BRYANLGH: BryanLGH Medical Center in Lincoln, Nebraska, has adopted multiple performance measurement systems to collect clinical outcome, financial, and patient satisfaction data into integrated databases. Data integration allows quality professionals at BryanLGH to identify quality issues from multiple perspectives and track the interrelated effects of improvement efforts. A CASE EXAMPLE: Data from the fourth quarter of 1997 indicated the need to improve processes related to cesarean section (C-section) deliveries. An interdisciplinary team was formed, which focused on educating nurses, physicians, and the community about labor support measures. Physicians were given their own rates of C-section deliveries.

RESULTS

The C-section rate decreased from 27% to 19%, but per-case cost increased. PickerPLUS+ results indicated that BryanLGH obstetric patients reported fewer problems with receiving information than the Picker norm, but they reported more problems with the involvement of family members and friends.

CONCLUSIONS

The data collected so far have indicated a decrease in the C-section rate and a need to continue to work on cost and psychosocial issues. A complete analysis of results was facilitated by integrated performance management systems. Successes have been easily tracked over time, and the need for further work on related processes has been clearly identified.

Can novice drivers be trained to scan for information that will reduce their likelihood of a crash?

Sixteen year old drivers are involved in 10.3 fatal crashes per 100 million vehicle miles, a rate almost double that of 18 year olds and almost eight times that of 45-64 year olds, who are the safest group of drivers. Crash rates are particularly higher during the first month of licensure and decline rapidly for about six months and 1000 miles and then much more slowly for at least two years, consistent with a typical learning curve. Research indicates that drivers who have their learner's permit or are just newly licensed have particular difficulties identifying areas of a scenario from which hidden risks could emerge. Standard driver education programs do not appear to address these difficulties adequately. This suggests that some alternative form of driver training could reduce the crashes, either in the classroom or on the road. A PC based program designed to teach drivers to recognize risks early on is shown to improve their awareness of hazards, both on an advanced driving simulator and on the road.

Imaging of the cervical spine and its role in clinical decision making

Thorough imaging of the cervical spine often requires more than one test. The many available options from which to choose can often lead to redundancy and confusion regarding the best test series. In an effort to make the process of choosing the most effective imaging series more efficient, we review the current literature on cervical imaging and, from the information gathered, construct a diagnostic imaging algorithm for evaluating the cervical spine.

Evaluation of graft patency during minimally invasive coronary artery bypass grafting with Doppler flow analysis

BACKGROUND

An objective method for determining intraoperative graft patency is an essential part of minimally invasive direct coronary artery bypass. This study compares angiography and Doppler methods for graft analysis during minimally invasive direct coronary artery bypass and presents long-term outcome in a cohort of patients.

METHODS

Between March and October 1997, 35 patients had elective minimally invasive direct coronary artery bypass procedures in which the left internal mammary artery was anastomosed to the left anterior descending coronary artery. Immediate graft patency was determined with intraoperative angiography using selective injection of the left internal mammary artery from a femoral approach and with Doppler flow analysis using a 1-mm, 20-MHz Doppler probe placed directly on the graft.

RESULTS

There was immediate perfect patency with brisk flow in 91% of patients (32 of 35). A normal Doppler study, defined as a diastolic predominant pattern with a diastolic flow velocity of greater than 15 cm/second, was found in all patients with normal angiograms. All patients with abnormal angiograms also had abnormal Doppler flow. Thus, Doppler analysis was 100% accurate for confirming graft patency and for detecting failed grafts. All abnormal grafts were successfully revised, which allowed 100% early patency. Operative mortality was 2.8% (1 of 35) and there have been no late deaths at a follow-up of more than 2 years. One patient required angioplasty of the anastomosis (1 of 34, 2.9%), but none have required subsequent surgical intervention.

CONCLUSIONS

Objective analysis of graft flow in the operating room is necessary to achieve 100% early graft patency with minimally invasive direct coronary artery bypass operations. Doppler analysis is the preferred initial method, because it is safe, accurate, and rapid.

Hsp90 is required for c-Mos activation and biphasic MAP kinase activation in Xenopus oocytes

During Xenopus oocyte maturation, the Mos protein kinase is synthesized and activates the MAP kinase cascade. In this report, we demonstrate that the synthesis and activation of Mos are two separable processes. We find that Hsp90 function is required for activation and phosphorylation of Mos and full activation of the MAP kinase cascade. Once Mos is activated, Hsp90 function is no longer required. We show that Mos interacts with both Hsp90 and Hsp70, and that there is an inverse relationship between association of Mos with these two chaperones. We propose that Mos protein kinase is activated by a novel mechanism involving sequential association with Hsp70 and Hsp90 as well as phosphorylation. We also present evidence for a two-phase activation of MAP kinase in Xenopus oocytes.

The framing of drivers' route choices when travel time information is provided under varying degrees of cognitive load

In two experiments, participants chose between staying on a main route with a certain travel time and diverting to an alternative route that could take a range of travel times. In the first experiment, travel time information was displayed on a sheet of paper to participants seated at a desk. In the second experiment, the same information was displayed in a virtual environment through which participants drove. Overall, participants were risk-averse when the average travel time along the alternative route was shorter than the certain travel time of the main route but risk-seeking when the average travel time of the alternative route was longer than the certain travel time along the main route. In the second experiment, in which cognitive load was higher, participants simplified their decision-making strategies. A simple probabilistic model describes the risk-taking behavior and the load effects. Actual or potential applications of this research include the development of efficient travel time information systems for drivers.

Dissociation of MAP kinase activation and MPF activation in hormone-stimulated maturation of Xenopus oocytes

MAP kinase activation occurs during meiotic maturation of oocytes from all animals, but the requirement for MAP kinase activation in reinitiation of meiosis appears to vary between different classes. In particular, it has become accepted that MAP kinase activation is necessary for progesterone-stimulated meiotic maturation of Xenopus oocytes, while this is clearly not the case in other systems. In this paper, we demonstrate that MAP kinase activation in Xenopus oocytes is an early response to progesterone and can be temporally dissociated from MPF activation. We show that MAP kinase activation can be suppressed by treatment with geldanamycin or by overexpression of the MAP kinase phosphatase Pyst1. A transient and low-level early activation of MAP kinase increases the efficiency of cell cycle activation later on, when MAP kinase activity is no longer essential. Many oocytes can still undergo reinitiation of meiosis in the absence of active MAP kinase. Suppression of MAP kinase activation does not affect the formation or activation of Cdc2-cyclin B complexes, but reduces the level of active Cdc2 kinase. We discuss these findings in the context of a universal mechanism for meiotic maturation in oocytes throughout the animal kingdom.

A novel role for glycogen synthase kinase-3 in Xenopus development: maintenance of oocyte cell cycle arrest by a beta-catenin-independent mechanism

We have examined the expression of glycogen synthase kinase-3beta in oocytes and early embryos of Xenopus and found that the protein is developmentally regulated. In resting oocytes, GSK-3beta is active and it is inactivated on maturation in response to progesterone. GSK-3beta inactivation is necessary and rate limiting for the cell cycle response to this hormone and the subsequent accumulation of beta-catenin. Overexpression of a dominant negative form of the kinase accelerates maturation, as does inactivation by expression of Xenopus Dishevelled or microinjection of an inactivating antibody. Cell cycle inhibition by GSK-3beta is not mediated by the level of beta-catenin or by a direct effect on either the MAP kinase pathway or translation of mos and cyclin B1. These data indicate a novel role for GSK-3beta in Xenopus development: in addition to controlling specification of the dorsoventral axis in embryos, it mediates cell cycle arrest in oocytes.

Reliability of magnetic resonance imaging in predicting disc material posterior to the posterior longitudinal ligament in the cervical spine. A prospective study

STUDY DESIGN

This was a prospective study to evaluate the accuracy of magnetic resonance imaging in predicting the presence of disc material posterior to the posterior longitudinal ligament (PLL), compared with the accuracy of intraoperative visual and tactile examination of the PLL.

OBJECTIVES

To determine the accuracy of magnetic resonance imaging in predicting the presence of disc material posterior to the PLL.

SUMMARY OF BACKGROUND DATA

Whether removal of the disc to the PLL is sufficient when performing an anterior cervical discectomy and fusion or it is necessary to explore the spinal canal by taking down the PLL is controversial.

METHODS

Fifty-four cervical levels were examined by magnetic resonance imaging before surgery to determine whether there was disc material posterior to the PLL. During surgery, the PLL was examined and probed for disruption. The ligament was taken down, and free fragments were identified and removed.

RESULTS

Of 54 levels, 12 were correctly identified by magnetic resonance imaging as having disc material posterior to the PLL, and 26 were correctly identified as not having disc material posterior to the PLL. Surgery confirmed that at 26 levels there was disc material posterior to the PLL. Of these 26, 23 (88.5%) had visual or palpable disruption of the PLL. Magnetic resonance imaging failed to predict disc material posterior to the PLL in 14 of the cases in which its presence was confirmed during surgery. Magnetic resonance imaging had 46.2% sensitivity and 92.9% specificity rates.

CONCLUSIONS

Because of low sensitivity, magnetic resonance imaging should be used cautiously for predicting free disc material posterior to the PLL. Visual or palpable examination of the PLL during surgery is more accurate for this prediction.

The acute phase response in the Sudan plated lizard, Gerrhosaurus major

The Sudan plated lizard (Gerrhosaurus major), previously reported to be an afebrile species, was utilized in a series of experiments to test for various aspects of the acute phase response. Treatment of individuals with the antibiotic Baytril resulted in a slight (0.5 degree C) but significant reduction in mean selected body temperature (MSBT), while treatment with saline did not lower MSBT. Nonantibiotic treatment individuals had depressed plasma iron levels (86.6 +/- 22.4 micrograms Fe 100 ml-1 plasma) and treatment with Baytril produced a significant increase in plasma iron concentration (186.8 +/- 19.5 micrograms Fe 100 ml-1 plasma). Necropsy of randomly selected individuals indicated that animals obtained from the commercial supplier had Aeromonas, Arthrobacter, Pseudomonas and Salmonella infections and antibiotic treatment eliminated these infections. The growth rate of Aeromonas sobria is reduced when the bacteria are grown at 32 degrees C and reduced iron concentration compared to 34.5 degrees C and low iron concentration, which suggests that a fever response may not be beneficial in reducing bacterial growth. Saline injected, bacteria injected and antibiotic injected Gerrhosaurus major have high plasma zinc concentrations compared to the previously studied febrile species, Dipsosaurus dorsalis. This difference suggests that zinc concentrations in afebrile species deserve further study.

Improving Nursing Education Classroom Environments

This study describes the first use of a classroom environment questionnaire with a class in nursing education. An instructor of nursing students monitored classes using such a questionnaire. The questionnaire used was the College and University Classroom Environment Inventory and it was used to obtain practical and useful information about the learning environment in two different classes. Collaborative changes were made in the classes to improve the classroom environment and consequently the learning situation. Any instructor of nursing students could use this same process with this instrument.

Visual search tasks: slowing of strategic and nonstrategic processes in the nonlexical domain

Some investigators have argued that aging affects the slowing of processes in nonlexical tasks more than it does the slowing of processes in lexical tasks, but that within task domains, the slowing is identical. Other investigators have argued that even within nonlexical tasks there is differential slowing such that aging affects processing speed more in (nonlexical) coordinative tasks than it does in (nonlexical) sequential tasks. Perhaps, more finely still, there is a differential slowing in coordinative nonlexical tasks. Toward this end, latent models of general and process-specific slowing in coordinative nonlexical tasks were formulated for older adults. A visual search task was then used to test the two types of models. It was found that a latent model of process-specific slowing explained significantly more of the variability than a latent model of general slowing, indicating that there is a differential slowing of processes among coordinative tasks within the nonlexical domain. It was also discovered that the coordinative process most greatly affected was that of deciding to terminate the search when no target was present in the display, indicating together with other studies a possible difference in the slowing of strategic processes among both coordinative and sequential tasks within the nonlexical domain, but no difference in the slowing of nonstrategic processes.

Sound localization: information theory analysis

Sound localization has been studied extensively. Curiously, although much is known about factors that affect errors, little is known about factors that influence response time. Three experiments were performed in an attempt to identify the separate influence of each of several different factors. All trials used a single broadband noise signal emanating from one of a subset of six loudspeakers equally spaced around the participant in the azimuthal plane. Both the size of the subset and the balance of relative probabilities from speaker to speaker were altered to evaluate the relationship between information content and the dependent variable, choice reaction time. Choice reaction time was found to be related to the information content of the sound stimulus in all cases. It was also found to be related to the presence of pairs of speakers that were symmetrically opposed in front of the behind the participant. Models of choice reaction time in a sound localization task have clear implications for practice. For example, they suggest that multiple auditory collision warnings may endanger drivers.

Toward a model of eye movement control in reading

The authors present several versions of a general model, titled the E-Z Reader model, of eye movement control in reading. The major goal of the modeling is to relate cognitive processing (specifically aspects of lexical access) to eye movements in reading. The earliest and simplest versions of the model (E-Z Readers 1 and 2) merely attempt to explain the total time spent on a word before moving forward (the gaze duration) and the probability of fixating a word; later versions (E-Z Readers 3-5) also attempt to explain the durations of individual fixations on individual words and the number of fixations on individual words. The final version (E-Z Reader 5) appears to be psychologically plausible and gives a good account of many phenomena in reading. It is also a good tool for analyzing eye movement data in reading. Limitations of the model and directions for future research are also discussed.

Minimizing fatigue during repetitive jobs: optimal work-rest schedules

Twenty women were asked to generate forces using a dynamometer that were consistent with one of three different work-rest schedules (a low-, medium-, and high-force schedule). Each work-rest schedule consisted of 6 identical blocks of 10 work-rest cycles. Each of the 10 work-rest cycles lasted 1 min. The first work-rest cycle in each block consisted of a 6-s maximal voluntary contraction and a 54-s rest. The remaining 9 work-rest cycles in each block consisted of a submaximal contraction and a rest period. The desired force of the submaximal contraction, the length of this contraction, and the duration of the rest period remained constant within schedules but varied across schedules. The amount of physiological work was kept constant among schedules. The fatigue that developed in the medium-force schedule was significantly lower than that developed in either the low- or high-force schedule. A model was developed that predicted the amount of fatiguable strength at the beginning and end of each contraction of a work-rest cycle. When fit to the results from the experiment, the model explained 94% of the variance. The model can be used to predict the work-rest schedule that minimizes fatigue in a given repetitive job, thereby potentially increasing productivity and reducing the incidence of cumulative trauma disorders.

A single fission yeast mitotic cyclin B p34cdc2 kinase promotes both S-phase and mitosis in the absence of G1 cyclins

Deletion of the fission yeast mitotic B-type cyclin gene cdc13 causes cells to undergo successive rounds of DNA replication. We have used a strain which expresses cdc13 conditionally to investigate re-replication. Activity of Start genes cdc2 and cdc10 is necessary and p34cdc2 kinase is active in re-replicating cells. We tested to see whether other cyclins were required for re-replication using cdc13delta. Further deletion of cig1 and puc1 had no effect, but deletion of cig2/cyc17 caused a severe delay in re-replication. Deletion of cig1 and cig2/cyc17 together abolished re-replication completely and cells arrested in G1. This, and analysis of the temperature sensitive cdc13-117 mutant, suggests that cdc13 can effectively substitute for the G1 cyclin activity of cig2/cyc17. We have characterized p56cdc13 activity and find evidence that in the absence of G1 cyclins, S-phase is delayed until the mitotic p34cdc2-p56cdc13 kinase is sufficiently active. These data suggest that a single oscillation of p34cdc2 kinase activity provided by a single B-type cyclin can promote ordered progression into both DNA replication and mitosis, and that the level of cyclin-dependent kinase activity may act as a master regulator dictating whether cells undergo S-phase or mitosis.

Further validation of a quadruplex STR DNA typing system: a collaborative effort to identify victims of a mass disaster

The relatively new, PCR-based technique of Short Tandem Repeat (STR) profiling has been used in the identification of the victims of a mass disaster. The analysis relied upon a recently developed multiplex reaction and the use of automated fluorescence technology to simulataneously analyse four tetrameric STR loci. The performance of the 'quadruplex' test was assessed by use of a collaborative study incorporating a blind trial and was demonstrated to be accurate, reliable and robust. Furthermore, the system proved to be highly successful despite the fact that many of the samples from the mass disaster scene were extremely degraded. The high success rate coupled with the discrimination power of the system enabled many severely decomposed human remains to be positively identified.

Proximal clavicle excision: an analysis of results

Medial clavicle excision has been reported by several authors, but few cases are documented, and long-term follow-up information is lacking. The purpose of this study was to examine the long-term results of medial clavicle excision in regard to function, pain, cosmesis, and complications. Fifteen patients ranging in age from 18 to 64 years (average 43 years) were evaluated an average of 4.6 years (range 1 to 14 years) after proximal clavicle excision. The indications for excision were unstable anterior subluxation/dislocation of the sternoclavicular joint (four cases), unstable posterior dislocation (one case), sternoclavicular osteoarthritis (nine cases), and proximal clavicle osteomyelitis (one case). An average of 2.9 cm of the medial clavicle was excised (range 1 to 4 cm). Fourteen of the 15 patients received significant relief of pain. On a strict grading scale four patients had an excellent result, five a good result, four a fair result, and two a poor result. Regeneration of the clavicle appeared to contribute to a poor result. No operative complications occurred. These findings aid our understanding of surgical options and outcome in the treatment of sternoclavicular joint disease.

Improved expression of a hybrid Streptomyces clavuligerus cefE gene in Penicillium chrysogenum

A hybrid cefE gene, encoding penicillin N expandase, was constructed by fusing the promoter sequences, Pcp, and terminator sequences, Pct from the Penicillium chrysogenum pcbC gene to the open reading frame (orf), cefEorf, from the Streptomyces clavuligerus cefE gene. The resulting hybrid gene, Pcp/cefE'orf/Pct, differed from a previously reported hybrid cefE gene contained on plasmid pPS65. The latter gene, Pcp/cefE'orf/Sct, contained the Pcp sequences fused to the S. clavuligerus cefE orf still attached to the S. clavuligerus terminator sequences, Sct. The new hybrid gene was transformed into P. chrysogenum on plasmid vector pRH6. Transformants were selected by phleomycin resistance conferred by a hybrid ble gene present on plasmid pRH6. The hybrid ble gene was formed by attaching Pcp sequences to the ble orf. Among transformants obtained with pRH6, one exhibited a 70-fold higher level of activity of penicillin N expandase than the best transformant previously obtained from a 10-fold larger population of pPS65 transformants. The penicillin N expandase activity in pRH6 transformant, 9EN-5-1, was fourfold higher than the activity in the S. clavuligerus strain used as the source of the cefE orf and 75% of the activity observed in an industrial strain of Cephalosporium acremonium. Sequencing of the junctions of the heterologous DNA in Pcp/cefEorf/Pct uncovered a modification of the cefE open reading frame introduced during construction of the hybrid gene; the modified open reading frame is designated cefE'orf.

Brinley plots and theories of aging: the explicit, muddled, and implicit debates

We evaluated the debates concerning Brinley plots and the associated theories of age-related slowing. We concluded that an explicit debate regarding a single-factor, general slowing model was no longer a debate as most, if not all, agree to the disconfirmation of that model. We address sources of confusion in the debates that have muddled the areas of genuine disagreement. When the confusion is lifted, the remaining debate centers, rightly, on evaluation of theories of aging. We show that Brinley plot analyses can lead to both falsely accepting and falsely rejecting theories of age-related slowing. Although plotting data most certainly can assist with the evaluation of cognitive theory, we argue that models of performance and learning must play a more central role in advancing theories of cognitive aging.

A systematic approach to the sampling of dental DNA

As investigations into the forensic aspects of DNA analysis continue, the human tooth will play a dual role in identification. Dentin and enamel provide a protective enclosure for genomic and mitochondrial DNA as well as providing the basis for radiographic, biochemical, and ultrastructural forensic studies. The purpose of this investigation is to establish technical guidelines, based on histology and experimental evidence, for the management and sampling of dental DNA. The anatomic location of dental DNA is discussed with emphasis on the conservation of tooth structure during sampling. Ten pairs of maxillary right and left third molars were sampled for DNA following storage for 18 weeks at ambient temperature and humidity. Right third molars were crushed, whereas the left third molars were sectioned conservatively prior to sampling the DNA. The quantity and quality of human DNA obtained from each tooth was compared, as well as the radiographic appearance of remaining hard tissue and the overall simplicity of each approach. DNA typing was performed, both sequence and length based analyses, comparing teeth from the same individual and teeth from different donors. The results of this study suggest that the odontologist will maximize the dental DNA yield by crushing the entire specimen but that substantial yields of human DNA can be obtained by using a conservative technique that preserves the tooth structure. In addition, the method of sampling does not affect the ability to perform DNA typing analyses.

Repetitive motion disorders: the design of optimal rate-rest profiles

Repetitive motion disorders of the upper extremities are the primary cause of lost time in hand-intensive industries. Typical remedies include the introduction of job aids and the redesign of the job. An alternative approach is considered here. Procedures are developed that can be used to determine the parameters of a job (e.g., the rate of work and the number and duration of the rest breaks) that minimize repetitive motion disorders and maximize productivity. It is shown that in theory the job parameters can be set so that one can achieve not only a decrease in repetitive motion disorders but also an increase in productivity. The application of the procedures to an actual manufacturing job requiring high-repetitive, high-force hand motions is discussed in detail.

Mitochondrial DNA sequence analysis of human skeletal remains: identification of remains from the Vietnam War

Deoxyribonucleic acid (DNA) sequence analysis of the control region of the mitochondrial DNA (mtDNA) genome was used to identify human skeletal remains returned to the United States government by the Vietnamese government in 1984. The postmortem interval was thought to be 24 years at the time of testing, and the remains presumed to be an American service member. DNA typing methods using nuclear genomic DNA, HLA-DQ alpha and the variable number of tandem repeat (VNTR) locus D1S80, were unsuccessful using the polymerase chain reaction (PCR). Amplification of a portion of the mtDNA control region was performed, and the resulting PCR product subjected to DNA sequence analysis. The DNA sequence generated from the skeletal remains was identical to the maternal reference sequence, as well as the sequence generated from two siblings (sisters). The sequence was unique when compared to more than 650 DNA sequences found both in the literature and provided by personal communications. The individual sequence polymorphisms were present in only 23 of the more than 1300 nucleotide positions analyzed. These results support the observation that in cases where conventional DNA typing is unavailable, mtDNA sequencing can be used for human remains identification.

Short tandem repeat loci: application to forensic and human remains identification

The short tandem repeat (STR) locus ACTBP2 (common name SE33) was analyzed for its potential use in forensic and human remains identification. PCR amplification conditions were determined, and an allele-specific ladder was generated so that discrete alleles could be scored. The allele frequency distributions were determined for both Caucasian and Black populations. The frequency data meets Hardy-Weinberg expectations, and the allele distributions were similar from one racial group to another and between ethnic groups. SE33 analysis was subsequently used to confirm the identification of human remains for the Office of the Armed Forces Medical Examiners.

Extraction, evaluation, and amplification of DNA from decalcified and undecalcified United States Civil War bone

Deoxyribonucleic acid (DNA) was extracted from documented skeletal specimens of U.S. Civil War soldiers to determine the need for decalcification prior to extraction. The polymerase chain reaction (PCR) was performed to determine if the calcification state had an effect on the ability to amplify the extracts and to determine how successful amplification would be with these aged specimens. Bone samples were pulverized to a fine powder and divided into two sets. One set of samples was decalcified and the other set left undecalcified. Both sets were extracted using an organic procedure. The results demonstrate that decalcification is not a necessary step in the extraction process and that the yield of DNA is generally two times greater when decalcification is omitted. Furthermore, the calcification state had no effect on the ability to perform the PCR. Although the extracted DNA was very degraded, a 410 base pair (bp) segment of the mitochondrial DNA (mtDNA) control region was amplified. These results suggest that DNA can be extracted and amplified from 125 year old bone without decalcification, which may assist in the identity of modern and historic forensic specimens.

Sexual abuse of children. The detection of semen on skin

OBJECTIVE

The detection of semen on the skin of children who present within 72 hours of an episode of sexual assault is critical to medical, forensic, and legal personnel. The Wood's Lamp, a UV light that causes semen to fluoresce, and four forensic laboratory techniques were compared to determine their sensitivity and decline in sensitivity over time.

DESIGN

A descriptive study.

PARTICIPANTS

Eleven adult female volunteers.

MEASUREMENTS/MAIN RESULTS

Semen was placed on the skin of the volunteers. Samples of the dried semen were assessed during a 28-hour period with the Wood's Lamp, microscopy, the acid phosphatase assay, and two assays for the prostatic protein p30 (counterimmunoelectrophoresis and enzyme-linked immunosorbent assay). The intensity of the Wood's Lamp fluorescence of semen diminished dramatically by 28 hours; in contrast, the fluorescence of urine persisted up to 80 hours. Over time, the p30-enzyme-linked immunosorbent assay technique was more sensitive than microscopy, the acid phosphatase assay, and p30-counterimmunoelectrophoresis in detecting semen on skin.

CONCLUSIONS

The Wood's Lamp is not a sensitive screening tool and should be used with caution. To improve the detection of sexual abuse in children, we recommend that the p30-enzyme-linked immunosorbent assay be used because of its potential as a more sensitive assay than those in current clinical use.

General slowing alone cannot explain age-related search effects: reply to Cerella (1991)

Cerella (1991) has argued that the performance of older adults in the Fisk and Rogers (1991) study is a linear function of the performance of younger adults that is independent of task-specific cognitive requirements. We demonstrate that this is not the case. First, we show that the scatter plot analyses used by Cerella can hide the very task-specific age-related slowing they were designed to reveal. Second, we demonstrate that the percentage of variance explained by such analyses can be misleading. Third, we show that there are reliable differences across tasks in the parameters relating younger and older adults' performance. Finally, we argue that the general, task-independent proportionate slowing that Cerella suggested explains so much of the variance in age-related performance is actually an average slowing that is a function of a relatively small task-independent and a relatively large task-dependent factor.

General slowing alone cannot explain age-related search effects: Reply to Cerella (1991)

Cerella (1991) has argued that the performance of older adults in the Fisk and Rogers (1991) study is a linear function of the performance of younger adults that is independent of task-specific cognitive requirements. We demonstrate that this is not the case. First, we show that the scatter plot analyses used by Cerella can hide the very task-specific age-related slowing they were designed to reveal. Second, we demonstrate that the percentage of variance explained by such analyses can be misleading. Third, we show that there are reliable differences across tasks in the parameters relating younger and older adults' performance. Finally, we argue that the general, task-independent proportionate slowing that Cerella suggested explains so much of the variance in age-related performance is actually an average slowing that is a function of a relatively small task-independent and a relatively large task-dependent factor.

Regulation of protein secretion by crinophagy in perfused rat liver

We examined the secretion of three serum proteins, albumin (RSA), alpha 2 mu-globulin (alpha 2 mu G), and transferrin (Trf), in the isolated perfused liver. Within 4 h of perfusion, only 20 to 35% of previously synthesized proteins were secreted by the liver into the recirculating medium. Low temperature inhibited the secretion of alpha 2 mu G and Trf, but not RSA. The amount of RSA secreted by the liver increased twofold in the presence of leupeptin, a proteinase inhibitor, or primaquine, a weak base capable of neutralizing acidic compartments. Neither drug affected Trf secretion, while the release of alpha 2 mu G was enhanced threefold by primaquine treatment. Only 55 to 70% of the total amount of these serum proteins present in the liver at the onset of perfusion could be accounted for after 4 h of perfusion. Our evidence suggests that these losses are due to protein degradation. The degradation of RSA and alpha 2 mu G was inhibited at 15 degrees C and by both leupeptin and primaquine. Contrary, RSA degradation was not altered when livers were perfused at 20 degrees C. Morphological techniques combined with immunological probes were utilized to identify possible intracellular sites of RSA degradation. RSA and cathepsin L were colocalized to large vacuoles found near the cell periphery. Entry of RSA into these vacuoles occurred at 20 degrees C but not at 15 degrees C. Our results using perfused rat livers suggest that as much as 40% of hepatic serum proteins are degraded via fusion of secretory vesicles with lysosomes (e.g., crinophagy).

Cloning and expression of a hybrid Streptomyces clavuligerus cefE gene in Penicillium chrysogenum

A hybrid cefE gene was constructed by juxtaposing promoter sequences from the Penicillium chrysogenum pcbC gene to the open reading frame of the Streptomyces clavuligerus cefE gene. In S. clavuligerus the cefE gene codes for the enzyme penicillin N expandase [also known as deacetoxycephalosporin C synthetase (DAOCS)]. To insert the hybrid cefE gene into P. chrysogenum the vector pPS65 was constructed; pPS65 contains the hybrid cefE gene and the Aspergillus nidulans amdS gene. The amdS gene encodes acetamidase and provides for dominant selection in P. chrysogenum. Protoplasts of P. chrysogenum were transformed with pPS65 and selected for the ability to grow on acetamide medium. Extracts of cells cultivated in penicillin production medium were analyzed for penicillin N expandase activity. Penicillin N expandase activity was detected in approximately one-third of the transformants tested. Transformants WG9-69C-01 and WG9-61L-03 had the highest specific activities of penicillin N expandase: 4.3% and 10.3%, respectively, relative to the amount of penicillin N expandase in S. clavuligerus. Untransformed P. chrysogenum exhibited no penicillin N expandase activity. Analysis of the penicillin V titer revealed that WG9-61L-03 produced titers equal to that of the recipient strain while the amount of penicillin V produced in WG9-69C-01 was reduced by five fold.

Understanding the central processing limit in consistent-mapping visual search tasks

Effects of load (i.e., the number of stimuli in the display) have been observed in multiple-frame studies using a consistent mapping of stimuli to responses (e.g., Fisher, 1982, 1984). In a series of four experiments, it is shown that these effects are not the consequence of differences across the high- and low-load conditions in either decision noise or peripheral masking. Additionally, it is shown that of two modes of limited capacity (a limited-channel and divided-capacity model) considered as possible explanations of load effects in tasks where subjects are required to locate a target, only one--the limited-channel model--is consistent with the results from all three location tasks. Finally, it is argued that the limited-channel model predicts not only the behavior observed in the four consistent-mapping experiments reported in this article but also the behavior observed in several related consistent-mapping tasks (Kleiss & Lane, 1986; Shiffrin & Gardner, 1972).

Efficient integrative transformation of Cephalosporium acremonium

A hybrid gene, IPNSp/HPTorf, was constructed by placing an 850 bp sequence of Cephalosporium acremonium DNA next to the 5' end of a bacterial open reading frame, HPTorf. The sequence was obtained as an 850 bp NcoI restriction fragment from the 5' non-coding region of the C. acremonium isopenicillin N synthetase (IPNS) gene. The HPTorf was obtained from a bacterial gene that coded for a hygromycin B phosphotransferase (HPT). Plasmids that contained IPNSp/HPTorf transformed C. acremonium to a stably maintained hygromycin B resistant phenotype. Southern analysis of total DNA from transformants demonstrated multiple integrations of the transforming DNA in the high molecular weight DNA of most transformants, but single integrations were observed in a few transformants. The number of transformants per microgram of DNA was about 100 times greater than for plasmids that contained the HPTorf without any juxtaposed eucaryotic promoter sequence. Plasmids with the promoterless HPTorf and plasmids with a truncated S. cerevisiae phosphoglycerate kinase promoter juxtaposed to the HPTorf transformed C. acremonium at equivalent low frequencies. Transformation of C. acremonium with linearized plasmid DNA produced at least 2-3 fold more transformants than the corresponding circular molecule. Several observations were made concerning protoplast formation and handling which made the transformation procedure more efficient and allowed a greater proportion of protoplasts to regenerate to viable walled cells. Plasmids were constructed that contained both the IPNSp/HPTorf and additional elements: fragments of C. acremonium ribosomal DNA (rDNA), or a fragment of C. acremonium mitochondrial DNA possessing activity as an autonomous replication sequence (ARS) in S. cerevisiae, or putative transcriptional termination/polyadenylation signals from the IPNS gene. These plasmids transformed C. acremonium at frequencies experimentally equivalent to those containing IPNSp/HPTorf without any of these additional elements.

Markov models and the utilization of mental health services: a study of endogenously depressed patients

Patients in the mental health care system typically make more or less irregularly spaced visits to psychiatrists, both within and between episodes of a given illness. A Markov model is constructed which can predict the utilization of psychiatric services for such patients. Unlike previous Markov models of utilization, the current model takes as its starting point a model of an actual disease, specifically, endogenous depression. It is shown how one can estimate the parameters of both the model of utilization and the model of depression using data which were collected for clinical research purposes. The models provide reasonable fits to the data. Several applications of the models are worked out. In addition to predicting the utilization of mental health services, the models can be used to predict incidence, prevalence and recovery rates and to predict the changes in utilization which parallel changes in treatment regimens.

Effects of hormones on postimplantation mouse embryos in vitro. II. Progesterone and estrogen

Mouse embryos at day 9 of development were cultured for 24 to 42 h in 50% fetal calf serum and 50% Waymouth's medium containing 0.5 micrograms/ml insulin supplemented with various amounts of progesterone and estradiol-17-beta. Unmodified medium contained approximately 0.2% of the normal maternal blood levels for that stage of pregnancy. The addition of 1 X 10(-7)M progesterone to the medium brought the level near that of the normal maternal circulating amount and appeared to be beneficial for in vitro development. After 24 h of cultivation there was a statistically significant increase in somite number, the number of embryos developing posterior limb buds, and protein accumulation over the control embryos. The addition of small amounts of estradiol-17 beta (1 X 10(-10)M) increased the protein accumulation of the embryo over that of progesterone alone and seems to enhance the beneficial effects of progesterone addition.