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Abstract: A genetically heterogeneous population of mice was tested for hearing at 8, 18, and 22 months by auditory brainstem response (ABR), and genotyped at 128 markers to identify loci that modulate late life hearing loss. Half of the test mice were exposed to noise for 2 hours at age 20 months. Polymorphisms affecting hearing at 18 months were noted on chromosomes 2, 3, 7, 10, and 15. Most of these loci had effects only on responses to 48 kHz stimuli, but a subset also influenced the auditory brainstem response at lower frequencies. Loci on chromosomes 4, 10, 12, and 14 had significant effects on hearing at 22 months in noise-exposed mice, and loci on chromosomes 10 and 11 had effects on mice not exposed to noise. Outer hair cell loss was modulated by polymorphisms on chromosomes 10, 11, 12, 17, and 19. Resistance to age-related hearing loss is thus modulated by a set of genetic effects, some age-specific, some frequency specific, some dependent on prior exposure to noise, and some of which compromise survival of cochlear hair cells. [Copyright &y& Elsevier]

Abstract: An integrated microfluidic device with on-chip photodiode is fabricated for single strand DNA (ssDNA) separation and detection. The microfluidic component is fabricated by parylene thin-wall technology. In order to achieve oxygen free environment for acrylamide gel polymerization in microfluidic channel, alumina inner coating is introduced to decrease parylene thin film permeability. On-chip high sensitivity photodiode successfully detected ssDNA fluorescence at the end of separation. Results show alumina is a good oxygen barrier which secures excellent cross-linking of the sieving matrix. Single base pair resolution for ssDNA separation in this device has been achieved. [Copyright &y& Elsevier]

Abstract: The aim of this study was to examine effects of polymorphic genes on vertebral bone morphology and mechanical properties. Genotypes from 525 18-month-old female mice were compared to geometric traits obtained from micro-computed tomography and mechanical properties from compression testing. Genetic markers were associated with traits on at least 13 different chromosomes, demonstrating the complexity of genetic control over vertebral form, function and aging. [Copyright &y& Elsevier]

An active microvalve that uses a meltable piston in place of a conventional solid material to obstruct fluid flow in a microfluidic channel has been developed. This phase change valve is simple to operate and requires no additional fabrication steps. The valve is inherently latched, reusable, and leak-proof (to at least 250 psi) and can be electronically addressed using resistive heaters. The valve has been characterized for a range of operational parameters that will serve as a design guide. For the designs tested, piston displacements of 5 mm or more in 1 s have been achieved. Valves 1.4 mm in length in a 50 μm × 200 μm channel have been integrated on a biochemical reaction device, and successful DNA amplification using PCR has been achieved. The phase change valve can be easily implemented in an array format that can be used to realize complex microfluiclic circuits. [ABSTRACT FROM AUTHOR]

Presents a study that examined the influence of social factors on a person's attitude towards people with mental illness in Oman. Comparison of the attitudes of medical students and relatives of psychiatric patients; Analysis of the public's attitude towards people with mental illness; Effect of demographic variables on the attitudes towards mental illness.

Some models of aging imply that late-life diseases, though roughly synchronous, are the result of distinct pathophysiological processes, each in turn influenced by polymorphisms at multiple loci. Other models suggest that the dramatic increase in later life of multiple forms of illness might reflect the outcome of a unitary process, of so-far unknown biochemical nature, that proceeds at a species-specific rate to increase the risk of many forms of disease and disability in parallel. We have previously reported the results of genetic linkage analyses documenting the ability of alleles at D9Mit110, D10Mit15, and D12Mit167, and an allele pair at D2Mit58 and D16Mit182 to predict longevity in mice bred as the progeny of (BALB/cJ x C57BL/6J)F1 mothers and (C3H/HeJ x DBA/2J)F1 fathers (the UM-HET3 stock). Here we report the results of post hoc analyses to test the hypothesis that the genes that extend the life span of mice dying of neoplastic diseases also extend the life span of mice that die of nonneoplastic causes. In all four cases we find that the genotype associated with increased survival in mice dying of cancer is also associated for a similar degree of life span extension in mice dying of other causes. For D9Mit110 and the combination of D2Mit58 and D16Mit182, the difference is statistically significant in both the neoplastic and nonneoplastic mouse groups. The data support the hypothesis that many forms of late-life disease may be influenced by shared pathophysiologic mechanisms that are under coordinated genetic control. [ABSTRACT FROM AUTHOR]

Recent research has shown that the prevalence of stroke incidents and the number of survivors in developing countries surpass those from developed countries. This study aimed to enumerate the prevalence of post-stroke psychiatric and cognitive symptoms among stroke survivors from West and South Asia and Africa through a systematic review and meta-analysis. Data from each country was systematically acquired from five major databases (PsycINFO, Web of Science, Scopus, PubMed/Medline, and Google Scholar (for any missing articles and grey literature)). Meta-analytic techniques were then used to estimate the prevalence of various post-stoke psychiatric and cognitive symptoms. A total of 36 articles were accrued from 11 countries, of which 25 were evaluated as part of the meta-analysis. The pooled prevalence of post-stroke depression as per the Hospital Anxiety and Depression Scale (HADS), Hamilton Depression Rating Scale, Patient Health Questionnaire, Schedules for Clinical Assessment in Neuropsychiatry (SCAN), Geriatric Depression Scale, and the Montgomery–Asberg Depression Rating Scale ranged from 28.00 to 50.24%. Pooled prevalence of post-stroke anxiety based on the HADS and SCAN was 44.19% and 10.96%, respectively. The pooled prevalence of post-stroke cognitive impairment as per the Mini-Mental Status Examination was 16.76%. This present review has suggested that both psychiatric and cognitive symptoms are common among stroke survivors. Concerted efforts are needed to institute robust studies using culturally sensitive measures to contemplate mechanisms that address the unmet needs of this vulnerable population. [ABSTRACT FROM AUTHOR]

Presents research which developed a device to analyze nanoliter-size DNA samples. Device capable of measuring aqueous reagent and DNA-containing solutions; Other capabilities; Components made using conventional photolithographic production techniques; Other potential uses for the device, especially in DNA analysis.

A common problem for healthcare providers is accurately tracking patients' adherence to medication and providing real-time feedback on the management of their medication regimen. This is a particular problem for eye drop medications, as the current commercially available monitors focus on measuring adherence to pills, and not to eye drops. This work presents an intelligent bottle sleeve that slides onto a prescription eye drop medication bottle. The intelligent sleeve is capable of detecting eye drop use, measuring fluid level, and sending use information to a healthcare team to facilitate intervention. The electronics embedded into the sleeve measure fluid level, dropper orientation, the state of the dropper top (on/off), and rates of angular motion during an application. The sleeve was tested with ten patients (age ≥65) and successfully identified and timestamped 94% of use events. On-board processing enabled event detection and the measurement of fluid levels at a 0.4 mL resolution. These data were communicated to the healthcare team using Bluetooth and Wi-Fi in real-time, enabling rapid feedback to the subject. The healthcare team can therefore monitor a log of medication use behavior to make informed decisions on treatment or support for the patient. [ABSTRACT FROM AUTHOR]

Background: Lean methodology helps maximize value by reducing waste, first by defining what value and waste are in a system. In ophthalmology clinics, value is determined by the number of patients flowing through the clinic for a given time. We aimed to increase value using a lean-methodology guided policy change, then assessed its impact on clinic flow using an automated radiofrequency identification (RFID) based real-time locating system (RTLS)., Methods: A total of 6813 clinical visits occurred at a single academic institution's outpatient glaucoma clinic between January 5, 2018 to July 3, 2018. Over that period, 1589 patients comprising 1972 (29%) of visits were enrolled, with 1031 clinical visits occurring before and 941 visits after a policy change. The original policy was to refract all patients that improved with pinhole testing. The policy change was not to refract patients with a visual acuity ≥20/30 unless a specific request was made by the patient. Pre-post analysis of an automated time-motion study was conducted for the data collected 3 months before and 3 months after the policy change occurred on March 30, 2018. Changes to process and wait times were summarized using descriptive statistics and fitted to linear mixed regression models adjusting for appointment type, clinic volume, and daily clinic trends., Results: One thousand nine hundred twenty-three visits with 1588 patients were included in the analysis. Mean [SD] age was 65.9 [14.7] years and 892 [56.2%] were women. After the policy change, technician process time decreased by 2.9 min (p < 0.0001) while daily clinical patient volume increased from 51.9 ± 16.8 patients to 58.4 ± 17.4 patients (p < 0.038). No significant difference was found in total wait time (p = 0.18) or total visit time (p = 0.83)., Conclusions: Real-time locating systems are effective at capturing clinical flow data and assessing clinical practice change initiatives. The refraction policy change was associated with reduced technician process time and overall the clinic was able to care for 7 more patients per day without significantly increasing patient wait time., (© 2022. The Author(s).)

Background: Obesity is a known factor for the development of abnormal respiratory physiology. However, several studies have found that obesity does not hinder functional recovery in patients hospitalized for postacute care following a stroke or cardiovascular event. This study was designed to determine the effect of overweight and obesity on patients with acute pulmonary disease, hospitalized in an inpatient rehabilitation facility (IRF)., Objective: To investigate the impact of body mass index (BMI) on indices of function, specifically, the functional independence measure (FIM) among patients with pulmonary related debility admitted to a rehabilitation hospital., Design: Retrospective cohort study., Setting: Pulmonary unit in an acute freestanding rehabilitation hospital., Patients: All patients admitted to an IRF with a diagnosis of pulmonary related debility over a 6-year period., Methods: The data used in the study included the patient height and weight (measured on admission) and FIM (scored on admission and discharge)., Main Outcome Measures: The primary study outcome measure was the change in FIM per day by the patients' BMI category., Results: For the 381 patients admitted during the observation period, BMI was compared with FIM score changes per day (FIM efficiency). After adjusting for age and sex, the FIM efficiency only slightly differed by BMI, failing to reach statistical significance. However, age did significantly influence the outcome (P = .05)., Conclusion: This study demonstrates that among a large group of patients with a pulmonary related debility, there was no statistically significant correlation between BMI and FIM efficiency. The overweight patients were similar in progression to those who were underweight, normal weight, and obese. However, this study found that increased age adversely affected the outcome of rehabilitation., Level of Evidence: III., (© 2019 American Academy of Physical Medicine and Rehabilitation.)

Background: Although many studies have demonstrated that obesity is correlated with an increased risk of chronic disease, some have reported a paradox by which those in the higher weight categories actually recover better during hospitalization. This study was designed to determine whether this obesity paradox is also reflected in the recovery of patients with traumatic brain injury (TBI) undergoing care in a rehabilitation hospital., Objective: To investigate the association between body mass index (BMI) and the functional progress of patients with TBI, admitted to a rehabilitation hospital., Design: Retrospective cohort study., Methods: The study included all patients admitted to the brain injury unit of a rehabilitation hospital over a 6-year period. The data used for this study included patient height and weight (measured on admission) and functional independence measurements (scored on admission and discharge)., Main Outcome Measures: Functional independence measure (FIM) change per day, BMI category., Results: For the 444 patients admitted, the overall FIM efficiency did not differ significantly by BMI (P = .93). After adjusting for age and gender, overweight and obese patients had the lowest FIM efficiency (1.04 for both groups), followed by the underweight and normal weight groups (1.11 and 1.26, respectively)., Conclusion: This study demonstrated that higher BMI was not significantly correlated with the rate of functional recovery among patients admitted to a rehabilitation hospital for TBI., Level of Evidence: III., (© 2019 American Academy of Physical Medicine and Rehabilitation.)

Objective: To investigate the effects of body mass index (BMI) on the rehabilitation process in patients with a recent knee replacement., Design: This retrospective cohort study included all patients admitted to a rehabilitation hospital, with a recent diagnosis of knee replacement and available hospital admission data including height and weight, between 2014 and 2017., Setting: Rehabilitation hospital., Participants: Study participants included patients who had undergone knee replacement surgery (N=742), with available BMI data., Interventions: None., Main Outcome Measures: FIM scores, including FIM change per day (FIM efficiency) by BMI category., Results: The chart review identified 742 patients who had undergone knee replacement surgery, with available BMI data. The identified patients ranged in age from 58 to 85 years, with a mean age of 70 years. Of the patients included in the study, 24 were male, 49 were female, 73 were within the normal weight class, 180 in the overweight class, 189 in the obese class I, 143 in the obese class II, and 157 patients were classified as obese class III. The mean FIM efficiency was highest in the obese class II category (3.96). In a multivariate analysis after controlling for age, obese classes II and III had significantly better FIM efficiency., Conclusion: This study did not demonstrate that obesity adversely affects the rate of recovery during hospitalization after knee replacement surgery., (© 2019 The Authors.)

A micro-plenoptic system was designed to capture the three-dimensional (3D) topography of the anterior iris surface by simple single-shot imaging. Within a depth-of-field of 2.4 mm, depth resolution of 10 µm can be achieved with accuracy (systematic errors) and precision (random errors) below 20%. We demonstrated the application of our micro-plenoptic imaging system on two healthy irides, an iris with naevi, and an iris with melanoma. The ridges and folds, with height differences of 10~80 µm, on the healthy irides can be effectively captured. The front surface on the iris naevi was flat, and the iris melanoma was 50 ± 10 µm higher than the surrounding iris. The micro-plenoptic imaging system has great potential to be utilized for iris disease diagnosis and continuing, simple monitoring.

Topical formulations of diclofenac, a nonsteroidal anti-inflammatory drug commonly prescribed to treat musculoskeletal complaints such as osteoarthritis, low back pain, and myofascial pain, are available in the form of a solution, gel, and patch. The topical application of diclofenac results in substantially lower systemic exposure to diclofenac compared with oral diclofenac, resulting in a more favorable side effect profile. To the authors' knowledge, this is the first case report of a lower gastrointestinal bleed associated with diclofenac topical patch use in a 77 yr-old-woman with a history of colonic mass and atrial fibrillation on antiplatelet therapy.

Objective: To investigate the association between body mass index (BMI) and the functional progress of patients with stroke, admitted to a rehabilitation hospital., Design: A retrospective cohort study., Setting: A freestanding university rehabilitation hospital stroke unit., Participants: All patients (N=819) admitted to the stroke unit of a rehabilitation hospital during the study., Interventions: Not applicable., Main Outcome Measures: The primary study outcome measure was the FIM efficiency of patients by BMI category., Results: For the 819 patients admitted during the observation period, BMI was compared with FIM score changes per day (FIM efficiency). After adjusting for age and sex, the FIM efficiency differed by BMI. The underweight group had the lowest FIM efficiency, followed by the obese and normal-weight subgroups. The overweight group had the highest FIM efficiency (P=.05) when compared with the obese subgroup., Conclusions: Among patients admitted to an acute rehabilitation hospital for stroke rehabilitation, overweight patients had better functional progress than did patients in the other weight categories., (Copyright © 2014 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.)

Rationale: The mechanism by which viruses cause exacerbations of chronic airway disease and the capacity of patients with cystic fibrosis (CF) to respond to viral infection are not precisely known., Objectives: To determine the antiviral response to infection in patients with CF., Methods: Sputum was collected from patients with CF with respiratory exacerbation. Viruses were detected in multiplex polymerase chain reaction (PCR)-based assays. Gene expression of 84 antiviral response genes was measured, using a focused quantitative PCR gene array., Measurements and Main Results: We examined 36 samples from 23 patients with respiratory exacerbation. Fourteen samples tested virus-positive and 22 virus-negative. When we compared exacerbations associated with rhinovirus (RV, n = 9) and influenza (n = 5) with virus-negative specimens, we found distinct patterns of antiviral gene expression. RV was associated with greater than twofold induction of five genes, including those encoding the monocyte-attracting chemokines CXCL10, CXCL11, and CXCL9. Influenza was associated with overexpression of 20 genes, including those encoding the cytokines tumor necrosis factor and IL-12; the kinases MEK, TBK-1, and STAT-1; the apoptosis proteins caspase-8 and caspase-10; the influenza double-stranded RNA receptor RIG-I and its downstream effector MAVS; and pyrin, an IFN-stimulated protein involved in influenza resistance., Conclusions: We conclude that virus-induced exacerbations of CF are associated with immune responses tailored to specific infections. Influenza induced a more potent response consisting of inflammation, whereas RV infection had a pronounced effect on chemokine expression. As far as we are aware, this study is the first to compare specific responses to different viruses in live patients with chronic airway disease.

We have developed a label-free viscosity-based DNA detection system, using paramagnetic beads as an asynchronous magnetic bead rotation (AMBR) microviscometer. We have demonstrated experimentally that the bead rotation period is linearly proportional to the viscosity of a DNA solution surrounding the paramagnetic bead, as expected theoretically. Simple optical measurement of asynchronous microbead motion determines solution viscosity precisely in microscale volumes, thus allowing an estimate of DNA concentration or average fragment length. The response of the AMBR microviscometer yields reproducible measurement of DNA solutions, enzymatic digestion reactions, and PCR systems at template concentrations across a 5000-fold range. The results demonstrate the feasibility of viscosity-based DNA detection using AMBR in microscale aqueous volumes.

Post-transcriptional RNA processing is an important regulatory control mechanism for determining the phenotype of eukaryotic cells. The processing of a transcribed RNA species into alternative splice isoforms yields products that can perform different functions. Each type of cell in a multi-cellular organism is presumed to actively control the relative quantities of alternative splice isoforms. In this study, the alternatively spliced isoforms of five mRNA transcription units were examined by quantitative reverse transcription-PCR amplification. We show that interindividual variation in splice-isoform selection is very highly constrained when measured in a large population of genetically diverse mice (i.e., full siblings; N = 150). Remarkably, splice-isoform ratios are among the most invariant phenotypes measured in this population and are confirmed in a second, genetically distinct population. In addition, the patterns of splice-isoform selection show tissue-specific and age-related changes. We propose that splice-isoform selection is exceptionally robust to genetic and environmental variability and may provide a control point for cellular homeostasis. As a consequence, splice-isoform ratios may be useful as a practical quantitative measure of the physiological status of cells and tissues.

Objective: To compare the safety of air insufflation as a contrast medium for percutaneous endoscopic gastrostomy (PEG) tube replacement verification with that of the more traditional method using positive contrast material (gastrograffin) under fluoroscopic guidance., Design: Retrospective case series comparing 2 radiographic procedures used for PEG tube verification at a rehabilitation hospital. The first series reviewed studies of patients over 1 year, during which the method of choice for PEG tube replacement verification was with air insufflation. The second series reviewed studies of patients over the subsequent year, during which the method of choice for PEG tube replacement verification was with gastrograffin., Setting: An inpatient rehabilitation hospital., Participants: Nineteen patients and 29 PEG tube replacements were identified that used air insufflation and 17 patients and 19 PEG tube replacements were identified that used gastrograffin., Interventions: Not applicable., Main Outcome Measures: Medical complications in a 2-week follow-up period as a result of the verification procedures., Results: There were no cases in either of the replacement procedures in which the PEG tube was found to not be in the gastrointestinal system. There was also no evidence at 2-week follow-up that any of the patients' complications were the result of either procedure., Conclusions: The air contrast procedure appears to be a relatively safe alternative procedure for PEG tube replacement verification.

In this paper, confocal laser scanning microscopy (CLSM) is used to detect and analyze DNA electrophoretic migration in a microchannel filled with in-situ polymerized cross-linked polyacrylamide. DNA distribution at the cross-section of the microchannel is observed to vary only slightly with the tested gel concentrations and the DNA sizes. However, in comparing with DNA electrophoresis using linear polymer solution (LPA), significant differences are observed in the distribution of DNA molecules on the observation plane using a cross-linked matrix (UV-polymerized polyacrylamide). Instead of a uniform signal boost upon the pass of one DNA band in linear polymer matrix, the electrophoretic process with cross-linked polyacrylamide presents a cross-section image with most DNA molecules aggregate near the vertical center of the microchannel during migration. This observation suggests an inhomogeneous nanostructure of in-situ polymerized cross-linked polyacrylamide in a microfabricated glass channel, consistent with SEM results. However, the phenomenon of DNA bands tending to focus in the vertical center along z-axis has not been previously reported. We also conclude from these observations that geometries containing fewer dead corners are desirable to minimize residual DNA in the microchannel.

Fraction collection following electrophoresis is of major importance for a variety of biological analyses. These assays typically need to identify specific fractions in the separated sample for further processing and require extraction of one or a group of fragments. In this paper, we have developed and characterized a technique to generate addressable electric fields for improved extraction during electrophoresis in microfluidic devices. The addressable electric field is achieved by applying a low bias voltage (1-2 V) to microelectrode pairs within the electrophoresis microchannel. Theoretical analysis shows the purity of the extracted sample can be improved as much as 30% over extraction without the shaped electric fields, and nearly 100% predicted yield can be achieved. We also describe the theoretical design of shaped electric fields by characterizing the optimal electrode geometry, field strength, channel configuration, and electrophoretic migration behavior needed for efficient band extraction.

A man in his late twenties with multiple injuries presented to a dedicated brain injury unit. A percutaneous endoscopic gastrostomy (PEG) tube was inserted for enteral feedings and medication delivery. During his inpatient course, the patient's PEG tube was inadvertently removed. House officers quickly replaced the tube by using 300 mL of room air as a contrast medium along with plain film radiography to verify correct placement. To our knowledge, this method has not previously been presented in the literature. The procedure significantly decreases the cost and eliminates the risks associated with endoscopic replacement or radiographic verification by using more common contrast media.

We have performed the Taqman beta-actin PCR system in high-surface-to-volume ratio (0.02-0.13 microm(-1)) SiO2 microchannels and observed the reaction yield and uniformity. The concentrations of the enzyme, magnesium chloride, and reaction template were varied in the reaction mix, and PCR amplification was performed in devices of various surface-to-volume ratios. We found that microchannels with higher surface-to-volume ratios required higher enzyme concentrations to achieve the same amplification efficiency. We investigated the possibility that the observed reaction nonuniformity was related to the specific adsorption of magnesium ions to the negatively charged SiO2 surface. The effect of several modifications to the reaction chemistry, the addition of the caged-magnesium dye DM-Nitrophen, the replacement of human DNA template with PCR product, and the coating of the microchannel surface with Teflon were all studied. These modifications resulted in improved reaction uniformity in the microchannels and present opportunities for further studies on enhancing the efficiency and uniformity of PCR in high surface-to-volume ratio SiO2 microchannels.

Objective: To compare the findings of the Useful Field of View (UFOV) test with those of conventional neuropsychologic tests to determine the utility of the UFOV test as a measure of attention in a population with brain injury., Design: Cohort study., Setting: Freestanding rehabilitation hospital., Participants: Fifteen inpatients with severe brain injury., Interventions: Not applicable., Main Outcome Measures: UFOV test, FIM\T instrument, length of stay (LOS), and standard neuropsychologic testing., Results: The UFOV subtest UF2 correlated strongly with the other 2 subtests, UF1 and UF3. The UF2 subtest correlated most strongly with paper and pencil tests of visual attention. The UF2 predicted 52% of the FIM change and 60% of the LOS variance, second only to admission FIM score, which predicted 75% and 80% of FIM change and LOS variance, respectively., Conclusions: Among the patients in our study, the UFOV test can be used to determine the visual divided attention of patients with acquired brain injury. The results also showed that the UFOV test correlated with LOS and FIM change in patients with acquired brain injury recovering in a rehabilitation facility. Because the UFOV test is much more quickly administered and scored than other measures of attention and divided attention, these results suggest that the UFOV test may provide an easy means to measure a critical variable in the population with head injury.

We have designed and constructed a microfabricated device for separation of double-stranded DNA fragments using a crosslinked sieving medium and spatially selective extraction of the desired fraction. Based on measuring the width and spacing of migrating bands, a narrow side channel is constructed perpendicular to the separation channel to collect the DNA fragments of interest. This selective collection technique was tested using a 100 base pair double-stranded DNA ladder. We successfully demonstrate selective extraction of the desired fragment with minimal interference from the adjacent bands in an electric field of 31 V/cm. We also achieve extraction of multiple DNA fragments using an array of microelectrodes in this side channel. The device uses cross-linked polyacrylamide gel matrix, allowing the separation to be performed in a distance of 1 cm or less and at a low electric field strength. Together with on-chip electrode, this design is amenable to integration with reaction chambers into a single device for portable genetic-based analysis.

A short focused pulse of light was used to selectively cut lambda-phage DNA molecules at specific restriction sites. Lambda DNA (48.5 kbp) was stretched and placed in a solution containing a restriction enzyme (Sma 1), caged magnesium ions (using a DM-Nitrophen complex), and a chelating agent (EDTA). When a pulse of UV light was directed at a particular location on the stretched DNA molecule, magnesium ions were released into solution. A series of binding reactions then occur in which the enzyme and the chelating agent compete for free Mg2+ ions. Since Sma 1 functions only in the presence of Mg2+, as is true of most endonucleases, the site(s) in the vicinity of the pulse (typically approximately 6 microm) were cut while other sites (three total for this DNA/enzyme pair) were not. The ratio of the concentration of the chelating agent to that of the magnesium ions was used to control the radius of this reaction zone with higher ratios leading to smaller, localized reaction areas. This optically based reaction mechanism could be useful to understand single molecule enzymatic kinetics, and when coupled with other DNA analysis techniques, this could be used to construct complex genotyping and sequencing devices that would analyze parts of single DNA molecules.

Upper-extremity deep vein thrombosis (UEDVT) was an understudied disease until recently. Previously thought of as benign, UEDVT has been shown in recent studies to pose a significant risk for pulmonary embolus and death. This article reviews the epidemiology, risk factors, clinical features, diagnostic tests, treatment options, complications, and prevention strategies for patients with UEDVT.

This study tests the relation between eye-movements and thought processing. Subjects were given specific modality tasks (visual, gustatory, kinesthetic) and assessed on whether they responded with distinct eye-movements. Some subjects' eye-movements reflected ongoing thought processing. Instead of a universal pattern, as suggested by the neurolinguistic programming hypothesis, this study yielded subject-specific idiosyncratic eye-movements across all modalities. Included is a discussion of the neurolinguistic programming hypothesis regarding eye-movements and its implications for the eye-movement desensitization and reprocessing theory.

Small body size has been associated with long life span in four stocks of mutant dwarf mice, and in two varieties of dietary restriction in rodents. In this study, small body size at ages 2-24 months was shown to be a significant predictor of life span in a genetically heterogeneous mouse population derived from four common inbred mouse strains. The association was strongest for weights measured early in adult life, and somewhat weaker, though still statistically significant, at later ages. The effect was seen both in males and females, and was replicated in an independent population of the same genetic background. Body size at ages 2-4 months was correlated with levels of serum leptin in both males and females, and with levels of IGF-I and thyroid hormone in females only. A genome scan showed the presence of polymorphic alleles on chromosomes 2, 6, 7 and 15 with significant effects on body weight at 2-4 months, at 10-12 months, or at both age ranges, showing that weight gain trajectory in this stock is under complex genetic control. Because it provides the earliest known predictor of life span, body weight may be usefully included in screens for induced mutations that alter aging. The evidence that weight in 2-month-old mice is a significant predictor of life span suggests that at least some of the lethal diseases of old age can be timed by factors that influence growth rate in juvenile rodents.

Objective: To describe the demographics, precipitating factors, substances and methods used for deliberate self-harm in Oman., Methods: Data were extracted from the Accident and Emergency (A & E) records of patients treated at the A & E units in Muscat from 1993 to 1998. Data were obtained form the history, and clinical findings resulting form deliberate self-harm., Results: During the 5-year study period, 123 persons presented to various hospitals in the Muscat area with injuries that resulted form deliberate self-harm. Most of these cases were women, students and unemployed. There was a high incidence of family, marital and psychiatric or social problems. The methods of self-harm were most often analgesics (such as paracetamol) and non-pharmaceutical chemicals., Conclusions: The rate of self-injurious behaviour is low in Oman, compared with other countries, including other Islamic countries. The data illustrate a rising rate and a tendency to ingest toxic doses of analgesics or non-pharmaceutical chemicals.