Put you in the problem: Effects of self-pronouns on mathematical problem-solving

Self-cues such as personal pronouns are known to elicit processing biases, such as attention capture and prioritisation in working memory. This may impact the performance of tasks that have a high attentional load like mathematical problem-solving. Here, we compared the speed and accuracy with which children solved numerical problems that included either the self-cue "you," or a different character name. First, we piloted a self-referencing manipulation with N = 52, 7 to 11 year-olds, testing performance on addition and subtraction problems that had either a single referent ("You"/"Sam") or more than one referent. We took into account operation and positioning of the pronoun and also measured performance on attention and working memory tasks. We found a robust accuracy advantage for problems that included "you," regardless of how many characters were included. The accuracy advantage for problems with a self-pronoun was not statistically associated with individual differences in attention or working memory. In our main study (9 to 11 year-olds, N = 144), we manipulated problem difficulty by creating consistently and inconsistently worded addition and subtraction problems. We found significantly higher speed and accuracy for problems that included "you." However, this effect varied by task difficulty, with the self-pronoun effect being strongest in the most difficult inconsistently worded, subtraction problems. The advantage of problems with a self-pronoun was not associated with individual differences in working memory. These findings suggest that self-cues like the pronoun "you" can be usefully applied in numerical processing tasks, an effect that may be attributable to the effects of self-cues on attention.

Effects of axitinib and lenvatinib on cardiovascular function and haemodynamic

Funding Acknowledgements

Type of funding sources: Public grant(s) – EU funding. Main funding source(s): EU Horizon 2020 Research and Innovation programme, under the Marie Skłodowska-Curie European Training Network

Background

The introduction of novel anticancer treatments, targeting vascular endothelial growth factor receptors (VEGFRs), has changed the therapeutic approach in oncology. However, with their introduction in clinical practice, unanticipated cardiovascular complications emerged, including hypertension, left ventricular dysfunction and thromboembolism [1]. Even though these therapeutics strongly affect haemodynamic balance in patients, the pathophysiological mechanisms by which they impair cardiovascular function are still largely unknown, leading to a reduction of therapeutic dosage or to a temporary or permanent treatment interruption [2].

Purpose

The severity of cardiovascular complications following the treatment with VEGFR inhibitors, along with the lack of antihypertensive strategies able to adequately manage these events, require an unequivocal and urgent assessment of their cardiovascular safety. This study aims to determine the extent to which VEGFR inhibitors impact on cardiovascular function, profiling their effect on regional haemodynamic responses. Their cardiovascular assessment represents a valuable opportunity to investigate the mechanisms underlying cardiovascular toxicities induced by these novel antiangiogenic treatments.

Methods

This study evaluated the haemodynamic effects of selected receptor tyrosine kinase inhibitors (RTKIs), namely axitinib and lenvatinib, in conscious and freely moving rats using the Doppler Flowmetry technique. Male Sprague Dawley Rats (350-450 g) were chronically implanted with pulsed Doppler flow probes (around the renal and mesenteric arteries, and the descending abdominal aorta) and catheters (jugular vein and distal abdominal aorta) [3]. Haemodynamic parameters were measured over 4 days, before and after daily administration of axitinib (3 and 6 mg/kg, 3 and 6 mg/kg/h for 1 h, i.v.), or lenvatinib (3 and 6 mg/kg, 3 and 6 mg/kg/h for 1 h, i.v.).

Results

Both axitinib and lenvatinib evoked a significant hypertensive response, which progressively increased over the 4 days. This pressor effect was associated with a notable decrease of vascular conductance in the hindquarters. Lenvatinib caused a more marked vasoconstriction in mesenteric and renal vessels when compared to axitinib, which only elicited a renal vasoconstrictive effect at the highest dose used.

Conclusions

This study showed that the axitinib- and lenvatinib-induced hypertensive response is associated with regionally selective vasoconstrictions, which consistently occur in the hindquarters vascular bed. However, their vasoconstrictive profile differs in the renal and mesenteric vasculature. In addition, the Doppler Flowmetry model showed to be a translational approach to predict the detrimental cardiovascular effects of these anticancer drugs, since the increase in blood pressure observed with this method reflects the hypertensive response reported in clinical practice.

The role of context in "over-imitation": Evidence of movement-based goal inference in young children

Children, as well as adults, often imitate causally unnecessary actions. Three experiments investigated whether such "over-imitation" occurs because these actions are interpreted as performed for the movement's sake (i.e., having a "movement-based" goal). Experiment 1 (N = 30, 2-5-year-olds) replicated previous findings; children imitated actions with no goal more precisely than actions with external goals. Experiment 2 (N = 58, 2-5-year-olds) confirmed that the difference between these conditions was not due to the absence/presence of external goals but rather was also found when actions brought about external goals in a clearly inefficient way. Experiment 3 (N = 36, 3-5-year-olds) controlled for the possibility that imitation fidelity was affected by the number of actions and objects present during the demonstration and confirmed that identical actions were imitated more precisely when they appeared to be more inefficient toward an external goal. Our findings suggest that movement-based goal inference encourages over-imitation.

Smoking in tuberculosis patients increases the risk of infection in their contacts

OBJECTIVE

To determine the risk of latent tuberculous infection (LTBI) among contacts of smokers with tuberculosis (TB).

METHODS

A study was conducted to determine the prevalence of LTBI among contacts of TB cases aged >14 years in Catalonia, Spain. A survey was carried out for each TB case and their contacts. LTBI was diagnosed using the tuberculin skin test (≥5 mm). The risk of LTBI associated with smoking was determined by multi-variate logistic regression analysis, with adjusted odds ratio (aOR) and their 95% confidence intervals (CI).

RESULTS

The smoking prevalence among TB cases was 40.7% (439/1079). The prevalence of LTBI among their contacts was 29.7% (2281/7673). It was higher among contacts of smoking index cases (35.3%) than among those of non-smokers (25.7%). Smoking was independently associated with an increased risk of LTBI among contacts (aOR 1.5, 95%CI 1.3-1.7), and was estimated to be responsible for 12.8% of infections.

CONCLUSIONS

Index case smoking increases the risk of LTBI and should be systematically investigated. A reduction in smoking could lower the risk of infection substantially.

Still Struggling: characteristics of youth with OCD who are partial responders to medication treatment

The primary aim of this paper is to examine the characteristics of a large sample of youth with OCD who are partial responders (i.e., still have clinically significant symptoms) to serotonin reuptake inhibitor (SRI) medication. The sample will be described with regard to: demographics, treatment history, OCD symptoms/severity, family history and parental psychopathology, comorbidity, and global and family functioning. The sample includes 124 youth with OCD ranging in age from 7 to 17 with a primary diagnosis of OCD and a partial response to an SRI medication. The youth are a predominantly older (age 12 and over), Caucasian, middle to upper income group who had received significant past treatment. Key findings include moderate to severe OCD symptoms, high ratings of global impairment, and significant comorbidity, despite partial response to an adequate medication trial. Considerations regarding generalizability of the sample and limitations of the study are discussed.

Influence of surgical or endovascular distal revascularization of the lower limbs on ischemic ulcer healing

AIM

Our aim is to analyze the ability of distal endovascular procedures, performed as first treatment option, to promote ischemic ulcer healing.

METHODS

Retrospective analysis of 91 primary distal procedures, 49 (53.8%) surgical and 42 (46.2%) endovascular, performed consecutively between January 2005 and December 2007 in patients with critical limb ischemia (CLI) and ischemic ulcers. Patient comorbidities, intervention duration time, postoperative hospital stay and complications were recorded. Ischemic ulcer healing time, patency, limb salvage and survival rates were compared between both groups. Data were included in a Cox regression model to determine predictive factors for healing

RESULTS

Endovascular therapy was associated with shorter intervention time (128±53 versus 301±91 min; P=0.001) and postoperative hospital stay (13±13 versus 19±14 days; P=0.05). Surgical procedures were associated with more local complications (28.6% versus 7.1% P=0.01), more readmissions for surgical wound complications (12.2% versus 0% P=0.03) and more early major amputations (16.3% versus 0% P=0.007). Ischemic ulcer healing in endovascular and surgical procedures was 80% versus 83% at 12 months (P=NS). Overall patency, limb salvage, survival and amputation-free survival with healed ulcers at 24 months in endovascular and surgical groups were 82% versus 82% (P=NS), 83% versus 72% (P=NS), 81% versus 79% (P=NS) and 63% versus 56% (P=NS). Diabetes mellitus (HR: 2.86 95% CI [1.44-5.68]), free ambulatory status (HR: 0.57 95% CI [0.33-0.98]) and the presence of severe wounds (HR: 2.73 95% CI [1.40-5.30]) were predictors for ulcer healing.

CONCLUSION

Endovascular and surgical distal procedures had a similar ulcer healing rate and limb salvage. Our experience supports endovascular-first strategy for CLI with tissue loss.

[Overall quality of life in persons with dementia]

AIM

To assess overall quality of life (QoL) among persons with dementia and to investigate variables associated with subjective perception of QoL.

PATIENTS AND METHODS

This was a cross-sectional study in six health and social care centres in Barcelona and Tarragona. Ninety nine persons with mild-moderate dementia, living at home with a known caregiver completed a face-to-face interview including sociodemographic information; health perception, a list of chronic medical conditions, depressive symptoms and activities of daily living. Overall QoL was measured with the single item of the World Health Organization Quality of Life-BREF.

RESULTS

40.6% assessed their overall QoL as very good/good. Univariate logistic regression analyses showed a lack of association between QoL with sociodemographic information, severity of dementia and functioning, but significant association between QoL with depressive symptoms, satisfaction with relationships, enjoying life and meaning in life. Ordinal and binary multivariate regression analysis showed that better perception of health and greater satisfaction with personal relationships was associated with better QoL. In addition, fewer depressive symptoms in the ordinal multivariate regression analysis and dementia severity and enjoy life in the binary regression analysis appeared significant.

CONCLUSIONS

Persons with mild-moderate dementia can inform about their overall QoL and subjective states. In addition to health status, other dimensions, as personal relationships and positive aspects should be systematically assessed in this population.

Absence of urinary opioid peptides in children with autism

OBJECTIVE

It has been claimed for a number of years that the urine of children with autism contains exogenously derived opioid peptides. This finding is said to reflect a disturbance in the integrity of the gut epithelium, act as a diagnostic marker for autism and predict treatment response to a diet excluding gluten and casein. The aim of the present study was to determine whether exogenous or endogenous peptides were present in the urine of children with autism or of control children.

DESIGN

Case-control study

SETTING

Cases were recruited from two tertiary referral centres specialising in autistic spectrum disorders, while controls were recruited from mainstream primary and secondary schools in the same geographical area.

PARTICIPANTS

65 boys with autism, mean age 7.4 years (range 5-11) and 158 control boys, mean age 7.8 years (range 4.2-11).

INVESTIGATIONS

Urine samples were examined by high pressure liquid chromatography (HPLC) and matrix assisted laser desorbtion ionisation-time of flight mass spectrometry (MALDI-TOF MS) for the presence of a number of putative opioid peptides.

OUTCOMES

There were no significant differences between the HPLC urinary profiles of the children affected by autism and the typically developing controls. In those cases where HPLC showed peaks in the locations at which opioid peptides might be expected to be found, MALDI-TOF established that these peaks did not, in fact, represent opioid peptides.

CONCLUSIONS

Given the lack of evidence for any opioid peptiduria in children with autism, opioid peptides can neither serve as a biomedical marker for autism nor be employed to predict or monitor response to a casein- and gluten-free diet.

Aplicación de las redes neuronales artificiales para la estratificación de riesgo de mortalidad hospitalaria

OBJECTIVE

To compare the ability of an artificial neural network (ANN) to predict hospital mortality with that of the Acute Physiology and Chronic Health Evaluation II (APACHE II) system and multiple logistic regression (LR). A secondary objective was to compare the allocation of individual probability among the models.

METHOD

The variables required for calculating the APACHE II were prospectively collected. A total of 1146 patients were divided (randomly 70% and 30%) into the Development (800) and the Validation (346) sets. With the same variables an LR model and an ANN were carried out (a 3-layer perceptron trained by algorithm backpropagation with bootstrap resampling and with 9 nodes in the hidden layer) in the Development set. The models developed were contrasted with the Validation set and their discrimination properties were evaluated using the area under the ROC curve (AUC [95% CI]) and calibration with the Hosmer-Lemeshow C (HLC) test. Differences between the probabilities were evaluated using the Bland-Altman test.

RESULTS

The Validation set showed an APACHE II with an AUC = 0.79 (0.75-0.84) and HLC = 11 (p = 0.329); LR model AUC = 0.81 (0.76-0.85) and HLC = 29 (p = 0.0001) and an ANN AUC = 0.82 (0.77-0.86) and HLC = 10 (p = 0.404). The patients with the most important differences in the allocation of probability between LR and ANN (8% of the total) were neurological. The worst results were found in trauma patients with an AUC of not greater than 0.75 in all the models. In respiratory patients, the ANN achieved the best AUC = 0.87 (0.78-0.91).

CONCLUSIONS

The ANN was able to stratify hospital mortality risk by using the APACHE II system variables. The ANN tended to achieve better results than LR, since, in order to work, it does not require lineal restrictions or independent variables. Allocation of individual probability differed in each model.

[Problems and proposals for improvement in the health care of economic immigrants]

OBJECTIVES

To analyse existing problems in health care to economic immigrants from the point of view of health and social professionals, health authorities and economic immigrants and to know which will be their proposals and priorities to improve economic immigrants's health assistance.

METHODS

Qualitative approach study made in Majorca island. (Spain). Three focus groups and three nominal groups with health and social workers from primary health care and hospital services were carried out as well as two partially structured interviews to health authorities, one Autonomic Authority and one Governmental Authority, and twelve partially structured interviews to economic immigrants identified trough key informants.

RESULTS

Health and social workers perceive the increase in the number of economic immigrants as a massive arrival. The main problems identified are: access restrictions to public health services for economic immigrants, the follow-up of these patients and diagnostic difficulties because lack of training in tropical medicine. Health and social workers's first proposal for improving this situation is their own training in tropical medicine. Autonomic Authority priorities are to guarantee access to public health services for all immigrants and to look actively for health problems in these population. Governmental Authority, instead, holds the legalization for all. In fact, economic immigrants are not concerned on health care because legalization and housing problems.

CONCLUSIONS

The main barriers identified by health and social workers in health care to economic immigrants are: access restrictions, follow-up and lack of training in tropical medicine. Health and social first proposal to improve this situation is their own training in tropical medicine while Autonomic and Central Authorities's priorities are not the same. For economic immigrants, health assistance is not their biggest concern.

Effects of chronic nicotine and methylphenidate in adults with attention deficit/hyperactivity disorder

Acute nicotine treatment has been found to reduce symptoms of attention deficit/hyperactivity disorder in adults (E. D. Levin, C. K. Conners, et al., 1996). In this study, chronic nicotine effects were compared with placebo and methylphenidate. Acute and chronic nicotine treatment significantly attenuated the rise in hit reaction time standard error over session blocks on the Conners Continuous Performance Test (C. K. Conners et al., 1996). Acute nicotine significantly reduced severity of clinical symptoms on the Clinical Global Impressions scale (National Institute of Mental Health, 1985). Nicotine caused a significant decrease in self-report of depressive mood as measured by the Profile of Mood States test (D. M. McNair, M. Lorr, & L. F. Droppleman, 1981). This small study (40 participants) provided evidence that nicotine treatment can reduce severity of attentional deficit symptoms and produce improvement on an objective computerized attention task.

Estimating age-related trends in cross-sectional studies using S-distributions

Growth trends in children are often based on cross-sectional studies, in which a sample of the population is investigated at one given point in time. Estimating age-related percentiles in such studies involves fitting data distributions, each of which is specific for one age group, and a subsequent smoothing of the percentile curves. The first requirement for this process is the selection of a distributional form that is expected to be consistent with the observed data. If a goodness-of-fit test reveals significant discrepancies between the data and the best-fitting member of this distributional form, an alternative distribution must be found. In practice, there is seldom an objective argument for selecting any particular distribution. Also, different distributions can yield very similar fits, so that any selection is somewhat arbitrary. Finally, the shapes of the observed distributions may change throughout the age range so drastically that no single traditional distribution can fit them all in a satisfactory manner. To overcome these difficulties in population studies, non-parametric smoothing techniques and normalizing transformations have been used to derive percentile curves. In this paper we present an alternative strategy in the form of a flexible parametric family of statistical distributions: the S-distribution. We suggest a method that guides the search for well-fitting S-distributions for groups of observed distributions. The method is first tested with simulated data sets and subsequently applied to actual weight distributions of girls of different ages. As far as the results can be tested, they are consistent with observations and with results from other methods.

Assessment and intervention for attention-deficit/hyperactivity disorder in the schools. Lessons from the MTA study

The MTA experience provides several lessons that may have clinical relevance. First, the MTA study identified six key instruments (see Table 1) that clinicians may want to use, but even on these instruments discrepancies in parent and teacher sources should be expected. We believe that unnoticed or unresolved discrepancies may be important factors contributing to the "disconnect" identified by the Consensus Conference Panel. Based on the MTA experience, we recommend a telephone call to the child's teacher, specifically to inquire about any discrepancy in the "source by domain" summary, as an efficient way to make a meaningful connection "... between developmental or educational (school-based) assessments and health-related (medical practice-based) services" for children with ADHD. Second, evaluation of pharmacologic intervention in the MTA study confirmed that teachers' reports are crucial for documenting efficacy, whereas parent reports are crucial for documenting side effects. Based on the MTA experience, we recommend frequent telephone contact with the teacher specifically to inquire about the peak effects and dissipation of effects of medication that are expected to occur during the school hours as a way to improve "... communication between diagnosticians and those who implement and monitor treatment in the schools."

Transdermal nicotine effects on attention

Nicotine has been shown to improve attentiveness in smokers and attenuate attentional deficits in Alzheimer's disease patients, schizophrenics and adults with attention-deficit/hyperactivity disorder (ADHD). The current study was conducted to determine whether nicotine administered via transdermal patches would improve attentiveness in non-smoking adults without attentional deficits. The subjects underwent the nicotine and placebo exposure in a counterbalanced double-blind manner. Measures of treatment effect included the Profile of Mood States (POMS), Conners' computerized Continuous Performance Test (CPT) of attentiveness and a computerized interval-timing task. The subjects were administered a 7 mg/day nicotine transdermal patch for 4.5 h during a morning session. Nicotine significantly increased self-perceived vigor as measured by the POMS test. On the CPT, nicotine significantly decreased the number of errors of omission without causing increases in either errors of commission or correct hit reaction time. Nicotine also significantly decreased the variance of hit reaction time and the composite measure of attentiveness. This study shows that, in addition to reducing attentional impairment, nicotine administered via transdermal patches can improve attentiveness in normal adult non-smokers.

Life events and post-traumatic stress: the development of a new measure for children and adolescents

BACKGROUND

A new interview measure of life events and post-traumatic stress disorder (PTSD) has been developed for children and adolescents aged 9 through 17, for use in both epidemiological and clinical studies. It includes 'high magnitude' events associated with PTSD as well as other 'low magnitude' events.

METHOD

The interview is designed as a module of the Child and Adolescent Psychiatric Assessment, an interviewer-based interview conducted with parent and child separately by trained lay interviewers. The module includes: (1) questions about a wide range of events; (2) a screen for key PTSD symptoms (painful recall, avoidance, hypervigilance); and (3) a detailed interview on all PTSD symptoms, including onset, duration, severity and co-morbidity. A test-retest reliability study was conducted with 58 parents and children, who were interviewed twice by different interviewers.

RESULTS

Intraclass correlations were 0.72 (child) and 0.83 (parent) for high magnitude events, and 0.62 (child) and 0.58 (parent) for low magnitude events. Kappa coefficients ranged from high for violence and sexual abuse to low for child reports of serious accidents and natural disasters. The reliability of the PTSD screen symptoms was fair to excellent (kappa = 0.40-0.79), and reliability of PTSD symptoms in those who passed the screen was excellent (ICC = 0.94-0.99). Compared with a general population sample (N = 1015), the clinic-referred subjects and their parents were twice as likely to report a traumatic event and, depending on the event, up to 25 times as likely to report symptoms of PTSD.

CONCLUSIONS

The results support the reliability and discriminant validity of the measure.

Assessment issues in treatment research of pediatric anxiety disorders: what is working, what is not working, what is missing, and what needs improvement

Reviewing the strengths and weaknesses of the rating scales for anxiety disorders makes it possible to select appropriate measures for use in a multisite treatment study of children and adolescents with DSM-IV-diagnosed anxiety disorders. Categorical diagnosis for study inclusion is provided by the K-SADS-PL, which has strong published psychometrics for anxiety disorders. Broadband symptom ratings of diverse pediatric psychiatric disorder can be obtained at baseline by the parent-scored Child Behavior Checklist. Anxiety symptom monitoring may be provided by the use of two psychometrically strong self-report measures, the MASC and the SCARED. Weekly global ratings are provided by the CGI whose scale points have been enhanced by detailed anchors; in addition, the raters all trained on practice vignettes to calibrate their scoring. Clinician-based ratings of the patient's anxiety symptoms can be carried out in adolescent patients using the HAM-A. The newly developed Children's Anxiety Rating Scale promises to cover the full pediatric age range as a clinician-based anxiety rating instrument, but must first be subjected to formal psychometric and treatment sensitivity evaluation.

[Gallium-67 (Ga-67) scintigraphy in tuberculosis and Mycobacterium avium-M. intracellulare infections in patients with HIV infections]

BACKGROUND

Diagnosis of mycobacterioses in HIV infected patients is sometimes difficult because of atypical findings. The aim of this study was to assess the utility of gallium scintigraphy in diagnosis of AIDS related mycobacterioses in patients with fever of unknown origin.

PATIENTS AND METHODS

We retrospectively reviewed the scans of 220 HIV(+) patients with fever (176 males [80%] and 44 females) who were evaluated with conventional diagnostic procedures at least of a week before.

RESULTS

Gallium scintigraphy was positive in 114 patients (51%) and negative in 106 (49%). Mycobacteria were isolated in 83 patients (38%), 75 of these patients (90%) had a positive scintigraphy (sensitivity 90%; specificity 71%). Positive predictive value was 66% and negative predictive value was 92%. Mycobacterium avium-M. intracellulare (MAI) and M. tuberculosis were diagnosed in 22 (29%) and 53 (71%) HIV(+) patients, respectively. Seventy one (94%) of 75 patients with mycobacterioses had gallium uptake in at least two localizations.

CONCLUSIONS

67Ga scintigraphy is very useful in HIV(+) patients with fever of unknown origin. A negative gallium scintigraphy makes unlikely the diagnosis of mycobacterioses.

Pharmacology of the selective serotonin reuptake inhibitors in children and adolescents

OBJECTIVE

To review the pharmacology of a new class of medications, the potent selective serotonin reuptake inhibitors (SSRIs), what is known about their metabolism in children and adolescents, and the practical clinical implications of such.

METHOD

Articles were retrieved through index Medicus searches for articles published during the past 10 years on the SSRIs and on pediatric pharmacology.

RESULTS

More than 300 articles were reviewed. Pharmacological data, derived from relevant adult literature, were summarized and extrapolated to children and from the limited pediatric literature. The SSRIs represent a new class of antidepressants with distinct advantages in their side effect profile and their broad therapeutic index over that seen with the tricyclic antidepressants. Their advantage of few anticholinergic side effects and limited cardiovascular toxicities are particularly relevant for the pediatric population. The SSRIs are metabolized via the hepatic cytochrome isoenzyme P450 system, and potential drug-drug interactions are reviewed.

CONCLUSIONS

The SSRIs appear to offer advantages over the tricyclic antidepressants. Unfortunately, pharmacokinetic data are lacking, and systematic studies of safety and efficacy in the pediatric age group are limited. Preliminary reports are encouraging, but further study is required.

Genotypic assessment of isoniazid and rifampin resistance in Mycobacterium tuberculosis: a blind study at reference laboratory level

Progress in understanding the basis of resistance to isoniazid (INH) and rifampin (RMP) has allowed molecular tests for the detection of drug-resistant tuberculosis to be developed. Consecutive isolates (n = 95) of Mycobacterium tuberculosis, from a Spanish reference laboratory investigating outbreaks of multidrug-resistant tuberculosis, were coded and sent to two external laboratories for genotypic analysis of INH and RMP resistance by PCR-single-strand conformation polymorphism (SSCP) analysis of specific regions of four genes: part of the coding sequence of katG and the promoter regions of inhA and ahpC for INH and the RMP resistance region of rpoB. After correction for the presence of outbreak strains and multiple isolates from single patients, RMP resistance was detected successfully by PCR-SSCP in > 96% of the RMP-resistant strains. PCR-SSCP had a sensitivity of 87% for INH resistance detection, and mutations in katG, inhA, katG-inhA, ahpC, and katG-ahpC were identified in 36.8, 31.6, 2.6, 13.2, and 2.6%, respectively, of the unique strains. Specificity was 100%. Molecular detection of resistance to the two main antituberculous drugs, INH and RMP, can be accomplished accurately by using a strategy which limits analysis to four genetic regions. This may allow the expedient analysis of drug resistance by reference laboratories.

Comparison of staples vs suturing for securing central venous catheters

OBJECTIVE

To determine whether skin staples can be used to secure central venous catheters as effectively as does suturing.

METHODS

A prospective, randomized trial of techniques to secure a central venous catheter was performed in a medical school human anatomy laboratory using human cadavers. Central lines were secured to the upper left thorax using either standard suture material (000 silk) or skin staples (5.7 mm x 3.8 mm). Once secured, an upward force was applied to the hub of the catheter perpendicular to the skin. The amount of force needed to break the catheter hub free of the skin was measured in kg. A total of 10 measurements were made for each of 3 methods for securing the catheters (2 sutures, 2 staples, 4 staples). In addition, the site of catheter breakage was recorded.

RESULTS

Those catheter hubs secured by 2 sutures required a mean force of 3.1 +/- 0.5 kg to cause breakage, and the break always occurred at the suture. Those hubs secured by 2 staples gave way at 3.0 +/- 0.3 kg (p = NS), while those secured with 4 staples gave way at 4.5 +/- 1.4 kg (p < 0.05). Although 1 hub did break, in all other stapled cases, the break occurred at the staple.

CONCLUSIONS

Based on this cadaver model, use of staples appears to be as effective as suturing for securing central venous catheters. Further studies of safety and time for placement are needed.

[Tuberculous hepatosplenic abscess, human immunodeficiency virus infection and multiresistant tuberculosis]

BACKGROUND

Tuberculosis (TB) with liver and/or spleen abscess (HSA) formation in HIV-positive patients is uncommon.

PATIENTS AND METHODS

One hundred and thirty-seven HIV positive patients with TB were studied from January 93 to June 95. Patients with tuberculous HSA were enrolled in the study. Diagnosis was obtained by recovery of Mycobacterium tuberculosis in clinical specimens and the presence of hypoechogenic lesions in liver and/or spleen.

RESULTS

M. tuberculosis isolates were resistant to some of the usual drugs in 51 patients. Twenty of these patients had HSA (39%) and in 18 patients the antibiotic sensitivity testing showed resistance to isoniazid, rifampin, ethambutol, and streptomycin. The remaining 86 patients had episodes of TB with drug-susceptible microorganism and only three patients had HSA (3%) (p < 0.001). The 23 patients with tuberculous HSA had a mean CD4+ lymphocyte count of 33 x 10(6) cells/L (2-111) and 7 had a previous episode of TB. The abdominal echography showed hepatosplenomegaly in all cases. Abscesses were located at the liver in 12 patients (52%), spleen in 18 (78%) and both organs in 7 (30%). In 16 cases a corticosteroid therapy was indicated. In the 3 patients with susceptible TB and HSA the clinical course was good. The 20 patients with resistant TB died.

CONCLUSION

Abdominal TB in HIV-positive patients and HSA formation appears to be more common in severely immunosuppressed patients, with resistant TB and its mortality rate is high. The response to therapy with antituberculous drugs is slow and sometimes the administration of corticosteroids is necessary for the resolution of symptoms.

Nicotine effects on adults with attention-deficit/hyperactivity disorder

Several lines of evidence suggest that nicotine may be useful in treating the symptoms of Attention-Deficit/Hyperactivity Disorder (ADHD). The current study was an acute, placebo-controlled double-blind experiment to determine whether nicotine might be useful as an alternative treatment of adults with ADHD symptomatology. Six smokers and 11 nonsmokers who were outpatient referrals for ADHD were diagnosed by DSM-IV criteria. Measures of treatment effect included the Clinical Global Impressions (CGI) scale, Hopkins' symptom check list (SCL-90-R), the Profile of Mood States (POMS), Conners' computerized Continuous Performance Test (CPT), the Stroop test, and an interval-timing task. The smokers underwent overnight deprivation from smoking and were given a 21 mg/day nicotine skin patch for 4.5 h during a morning session. The nonsmokers were given a 7 mg/day nicotine skin patch for 4.5 h during a morning session. Active and placebo patches were given in a counter-balanced order approximately 1 week apart. Nicotine caused a significant overall nicotine-induced improvement on the CGI. This effect was significant when only the nonsmokers were considered, which indicated that it was not due merely to withdrawal relief. Nicotine caused significantly increased vigor as measured by the POMS test. Nicotine caused an overall significant reduction in reaction time (RT) on the CPT, as well as, with the smokers, a significant reduction in another index of inattention, variability in reaction time over trial blocks. Nicotine improved accuracy of time estimation and lowered variability of time-estimation response curves. Because improvements occurred among nonsmokers, the nicotine effect appears not to be merely a relief of withdrawal symptoms. It is concluded that nicotine deserves further clinical trials with ADHD.

A survey of eye and vision care in Oklahoma

We examined the spectrum of vision care intensity, and the relationships of the three principal providers of vision care in Oklahoma. They were active family and general physicians (MD and DO), ophthalmologists (MD and DO), and optometrists. There were 1,356 surveys mailed to the three groups. We determined that vision care services in Oklahoma appear very accessible, are well distributed and generally affordable. The referral patterns appear to be less than optimal and optometrists are not fully utilized. This added cost and travel time for patients.

Reciprocal overshadowing between intra-maze and extra-maze cues

In three experiments, rats learned a maze discrimination where the location of food was defined either by reference to extra-maze cues alone, or by both extra- and intra-maze cues. Experiment 1 confirmed earlier results in showing that the presence of intra-maze cues failed to overshadow learning about extra-maze cues, in spite of the former's apparently greater salience. Experiment 2, however, suggested that this result was an artefactual consequence of differences between groups in the proportion of reinforced and unreinforced trials during the course of discriminative training. In Experiment 3, the discrimination was taught by a series of reinforced and unreinforced placement trials, and a significant overshadowing effect was observed. Intra-maze and extra-maze cues seem to compete for association with reinforcement in exactly the same way as any other cues.

An assessment of the adequacy of self-care by adult asthmatics

Little is known about how individuals who have chronic disease actually manage their symptoms. This study involving a community-based population of 157 adult asthmatics assesses their ability to take care of their disease and to alter their behavior following a change in symptoms. Multiple techniques (interview, direct observation, and diary) were used to determine their behaviors with respect to medications and physician use; there were then compared with criteria defining the requisite level of a behavior to reduce symptoms. Of the population assessed, 66% had no bronchodilator medication at home, 24% used an inhaler ineffectively, and 68% did not see a physician regularly. When faced with increasing symptoms, at least 40% of the asthmatics did not perform three basic and appropriate behaviors in medication use and physician contact. If physicians and other health care providers could decrease the frequency of these inappropriate self-care behaviors, it could result in improved health.

Effects of high dosage delta-9-tetrahydrocannabinol on sleep patterns in man

Electroencephalographic readings and eye movement were recorded in experienced marijuana users under placebo and tetrahydrocannabinol (THC). Four subjects were studied for 3 baseline nights, 3 nights under initial dosage of 70 mg/day, the last 3 nights of a 2-wk period of 210 mg/day, and the first 3 nights of withdrawal. Three other subjects were studied only during the latter 2 conditions. Administration of THC significantly reduced eye movement activity during sleep with rapid eye movements (REM) and, to a lesser extent, the duration of REM itself. Withdrawal led to increases above baseline in both measures but the "rebound" effect was greater for eye movement. Stage 4 sleep tended to increase on drug, but this effect was not statistically significant. On withdrawal, stage 4 sleep decreased significantly; this change was marked only on the first withdrawal night. The functional or biological significance of these changes is unclear. Nevertheless, these are the most marked effects of THC on brain electrical activity demonstrated thus far. Since its pattern of effects on sleep appears unique to THC, this drug may prove to be a valuable tool in the elucidation of the pharmacology of sleep. Possible relations between effects on sleep pattern and on behavior are discussed.

Absence of REM rebound after barbiturate withdrawal

Administration of three different barbiturates reduced rapid eye movement (REM) sleep. Drug withdrawal led to a return to baseline REM] values without significant overshoot. Similar results are observed with administration of benzodiazepines in pharmacologically equivalent dosages; therefore, a distinction between these two drug classes on the basis of withdrawal effects on the sleep electroencephalogram appears unwarranted. Further investigation is required determine why high REM levels are sometimes associated with the withdrawal of sedative-hypnotic agents.