Attributing social and physical meaning to ambiguous visual displays in individuals with higher-functioning autism spectrum disorders

The weak central coherence (WCC) account of autism characterizes the learning style of individuals with this condition as favoring localized and fragmented (to the detriment of global and integrative) processing of information. This pattern of learning is thought to lead to deficits in aspects of perception (e.g., face processing), cognition, and communication (e.g., focus on disjointed details rather than "gist" or context), ultimately leading to social impairments. This study was carried out to examine whether WCC applies to social and to non-social aspects of learning alike, or, alternatively, some areas of learning (e.g., physical reasoning) are spared in autism. classic social animation as quantified in the Social Attribution Task (SAT) () and a novel animation involving physical reasoning (the Physical Attribution Task; PAT) were used to test the domain specificity of the WCC hypothesis. A pilot study involving a reference group of typically developing young adults and a group of individuals with higher-functioning autism spectrum disorders (ASDs) revealed gender differences in the reference group in regards to performance on the PAT (males outperformed females). In a follow-up case-control comparison involving only males where the ASD group was matched on age and IQ to a typically developing (TD) group of children, adolescents, and adults, the ASD group showed lower SAT scores and comparable PAT scores relative to the TD group. The interaction of diagnostic group by task was highly significant, with little overlap between the groups in the distributions of SAT minus PAT scores. These results indicated preserved integrative skills in the area of physical attribution in the ASD group, thus failing to support the WCC account as a domain-independent (or more general) model of learning in autism, while highlighting the centrality of the social deficits in the characterization of learning style in the autism spectrum disorders.

Assessing the Performance of Overseas Tuberculosis Screening Programs

BACKGROUND

Tuberculosis cases in foreign-born persons account for more than 50% of all tuberculosis cases in the United States. The Institute of Medicine has recommended enhancing overseas screening as one measure to support tuberculosis elimination efforts. We assessed the ability of overseas tuberculosis screening (chest radiograph followed by 3 acid-fast bacilli sputum smears for persons with abnormal chest radiographs [suggestive of active tuberculosis]) to detect pulmonary tuberculosis disease among US-bound immigrants with abnormal chest radiographs.

METHODS

During October 1998 to October 1999, 14 098 US immigrant visa applicants were screened overseas in Vietnam. Adult applicants with abnormal chest radiographs were enrolled to assess screening test characteristics among this group using mycobacterial culture as the gold standard for pulmonary tuberculosis disease diagnosis. Risk factors for pulmonary tuberculosis disease were also evaluated.

RESULTS

Among 1179 adult applicants with abnormal chest radiographs, 82 (7.0%) had positive acid-fast bacilli smear results, and 183 (15.5%) had positive Mycobacterium tuberculosis culture results (pulmonary tuberculosis disease). The sensitivity, specificity, and positive and negative predictive values of serial acid-fast bacilli screening among this group were 34.4% (63/183), 98.1% (977/996), 76.8% (63/82), and 89.1% (977/1097), respectively. Risk factors for pulmonary tuberculosis disease included younger age (18-34 years), no history of tuberculosis or treatment, reported symptoms, and cavitation or consolidation on chest radiograph.

CONCLUSIONS

The ability of current overseas screening to detect tuberculosis among immigrants with abnormal chest radiographs is low. Improved diagnostic methods, enhanced screening measures, and postmigration follow-up are essential to control tuberculosis among immigrants and support US and global tuberculosis elimination.

Understanding the Influence of Polymorphism on Phonon Spectra: Lattice Dynamics Calculations and Terahertz Spectroscopy of Carbamazepine

Rigid molecule atomistic lattice dynamics calculations have been performed to predict the phonon spectra of the four polymorphs of carbamazepine, and these calculations predict that there should be differences in the spectra of all four forms. Terahertz spectra have been measured for forms I and III, and there are clearly different features between polymorphs' spectra, that are accentuated at low temperature. While carbamazepine adopts the same hydrogen bonded dimers in all of its known polymorphs, the calculations show that differences in packing arrangements of the dimers lead to changes in the frequency ranges for each type of hydrogen bond vibration, giving a physical explanation to the observed differences between the spectra. Although the agreement between calculated and observed spectra does not allow a definitive characterization of the spectra, it is possible to make tentative assignments of many of the observed features in the terahertz region for the simpler form III; we can only make some tentative assignments of specific modes in the more complex spectrum of form I. While harmonic rigid molecule lattice dynamics shows promise for understanding the differences in spectra between polymorphs of organic molecules, discrepancies between observed and calculated spectra suggest areas of improvement in the computational methods for more accurate modeling of the dynamics in molecular organic crystals.

Improved sensitivity of sputum smear microscopy after processing specimens with C18-carboxypropylbetaine to detect acid-fast bacilli: a study of United States-bound immigrants from Vietnam

The goal of this study was to evaluate the effect of the specimen-processing method that uses the detergent C18-carboxypropylbetaine (CB-18) on the sensitivity of acid-fast bacillus (AFB) staining. Vietnamese immigrants with abnormal chest radiographs provided up to three sputum specimens, which were examined for acid-fast bacilli by use of direct auramine and Ziehl-Neelsen staining. The remaining sputum was split; half was cultured, and the other half was incubated with CB-18 for 24 h, centrifuged, and examined for AFB by both staining methods. CB-18 processing improved the sensitivity of AFB staining by 20 to 30% (only differences in auramine sensitivity were statistically significant) but reduced specificity by approximately 20% (P < 0.05). These findings have direct utility for overseas migrant tuberculosis screening programs, for which maximizing test sensitivity is a major objective.

Differential chemosensory function and receptor expression of splanchnic and pelvic colonic afferents in mice

Lumbar splanchnic (LSN) and sacral pelvic (PN) nerves convey different mechanosensory information from the colon to the spinal cord. Here we determined whether these pathways also differ in their chemosensitivity and receptor expression. Using an in vitro mouse colon preparation, individual primary afferents were tested with selective P2X and transient receptor potential vanilloid receptor 1 (TRPV1) receptor ligands. Afferent cell bodies in thoracolumbar and lumbosacral dorsal root ganglia (DRG) were retrogradely labelled from the colon and analysed for P2X3- and TRPV1-like immunoreactivity (LI). Forty per cent of LSN afferents responded to alpha,beta-methylene adenosine 5'-triphosphate (alpha,beta-meATP; 1 mm), an effect that was concentration dependent and reversed by the P2X antagonist pyridoxyl5-phosphate 6-azophenyl-2',4'-disulphonic acid (PPADS) (100 microm). Significantly fewer PN afferents (7%) responded to alpha,beta-meATP. Correspondingly, 36% of colonic thoracolumbar DRG neurones exhibited P2X3-LI compared with only 19% of colonic lumbosacral neurones. Capsaicin (3 microm) excited 61% of LSN afferents and 47% of PN afferents; 82% of thoracolumbar and 50% of lumbosacral colonic DRG neurones displayed TRPV1-LI. Mechanically insensitive afferents were recruited by alpha,beta-meATP or capsaicin, and were almost exclusive to the LSN. Capsaicin-responsive LSN afferents displayed marked mechanical desensitization after responding to capsaicin, which did not occur in capsaicin-responsive PN afferents. Therefore, colonic LSN and PN pathways differ in their chemosensitivity to known noxious stimuli and their corresponding receptor expression. As these pathways relay information that may relate to symptoms in functional gastrointestinal disease, these results may have implications for the efficacy of therapies targeting receptor modulation.

Results of tuberculosis screening in applicants for migration in Vietnam and Cambodia

SETTING

Pre-migration medical screening programmes in Ho Chi Minh City, Vietnam and Phnom Penh, Cambodia.

OBJECTIVE

To compare the rates of newly diagnosed bacteriologically confirmed tuberculosis (TB) in a cohort of migration applicants in Vietnam and Cambodia with current estimates of the TB burden in these countries.

DESIGN

Interviews and medical screening of 5108 Vietnamese and 910 Cambodian migration applicants who applied for an Australian visa.

RESULTS

On initial testing, the rate of bacteriologically confirmed TB among the Vietnamese cohort was 157 per 100,000 population compared to 989/100,000 among the Cambodian cohort. When cases detected during follow-up testing were included, the rate in the Vietnamese cohort was 489/100,000 compared to 1209/100,000 in the Cambodian cohort.

CONCLUSIONS

Although it has been suggested that the rate of newly diagnosed bacteriologically confirmed TB among migration applicants would underestimate the prevalence of TB in the Vietnamese and Cambodian populations, the rates found were substantially higher than current point estimates of the prevalence of TB, particularly for Vietnam. Our findings suggest that current published estimates of the tuberculosis burden in Vietnam and Cambodia may be conservative.

Treatment outcome of multidrug-resistant tuberculosis among Vietnamese immigrants

OBJECTIVE

To review the outcome for MDR-TB treatment among potential migrants from Vietnam.

SETTING

All cases of documented MDR-TB treated by the International Organization of Migration (IOM) in Vietnam from 1989 to 2000 were reviewed.

METHODS

MDR-TB was defined as isoniazid- and rifampicin-resistant Mycobacterium tuberculosis. All cases of TB treated by the IOM and recorded in the computerised database were reviewed to identify MDR-TB cases. Demographics, chest radiograph results, drug resistance, drug use and dosage, duration of treatment, and outcome were analysed.

RESULTS

Forty-four cases of MDR-TB were identified. Treatment consisted of ambulatory directly observed treatment with an 8-drug protocol: isoniazid, rifampicin, pyrazinamide, ethambutol, capreomycin, ethionamide, ofloxacin and cycloserine. This initial protocol was modified due to drug availability or drug intolerance. Patients were treated with a median of 8 drugs (range 6-12). Mean duration of treatment for MDR-TB was 23.0 (SD+/-11.4) months. Thirty-eight (86%) patients were cured and emigrated, one failed treatment (2%), three were lost to follow-up (7%) and two died (4%).

CONCLUSION

Treatment for MDR-TB provided by the IOM was effective in preparing a low-income population for migration.

European consensus on diagnosis and treatment of germ cell cancer: a report of the European Germ Cell Cancer Consensus Group (EGCCCG)

Germ cell tumour is the most frequent malignant tumour type in young men with a 100% rise in the incidence every 20 years. Despite this, the high sensitivity of germ cell tumours to platinum-based chemotherapy, together with radiation and surgical measures, leads to the high cure rate of > or = 99% in early stages and 90%, 75-80% and 50% in advanced disease with 'good', 'intermediate' and 'poor' prognostic criteria (IGCCCG classification), respectively. The high cure rate in patients with limited metastatic disease allows the reduction of overall treatment load, and therefore less acute and long-term toxicity, e.g. organ sparing surgery for specific cases, reduced dose and treatment volume of irradiation or substitution of node dissection by surveillance or adjuvant chemotherapy according to the presence or absence of vascular invasion. Thus, different treatment options according to prognostic factors including histology, stage and patient factors and possibilities of the treating centre as well may be used to define the treatment strategy which is definitively chosen for an individual patient. However, this strategy of reduction of treatment load as well as the treatment itself require very high expertise of the treating physician with careful management and follow-up and thorough cooperation by the patient as well to maintain the high rate for cure. Treatment decisions must be based on the available evidence which has been the basis for this consensus guideline delivering a clear proposal for diagnostic and treatment measures in each stage of gonadal and extragonadal germ cell tumour and individual clinical situations. Since this guideline is based on the highest evidence level available today, a deviation from these proposals should be a rare and justified exception.

Bleomycin, vincristine, cisplatin/bleomycin, etoposide, cisplatin chemotherapy: an alternating, dose intense regimen producing promising results in untreated patients with intermediate or poor prognosis malignant germ-cell tumours

Patients with poor and intermediate prognosis metastatic germ-cell tumours (MGCTs) are at a significant risk of relapse after standard platinum-based chemotherapy. Novel treatment regimens are required to improve survival. Dose intense, alternating combinations of drugs with known activity in germ-cell tumours represents one approach. In all, 43 patients with IGCCCG intermediate/poor prognosis MGCT were treated with a dose intense regimen alternating bleomycin, vincristine, cisplatin (BOP) with bleomycin, etoposide, cisplatin (BEP) to a maximum of three cycles. Data were collected on the maintenance of dose intensity, toxicity, response, progression-free (PFS) and overall survival (OS). The complete response rate was 58%; a further 7% of patients being rendered disease free by resection of viable residual tumour. With a median follow-up of more than 4 years in surviving patients, 3-year OS and PFS rates of 81% (95% CI: 66–91%) and 72% (95% CI: 56–83%) are seen, respectively. Bleomycin, vincristine, cisplatin (BOP)/bleomycin, etoposide, cisplatin (BEP) was well tolerated, with 86% of patients completing all planned courses. Toxicity was predominantly haematological with common toxicity criteria grade III neutropenia in 90% of patients. Cisplatin neuropathy and bleomycin-induced pulmonary toxicity represented the most significant nonhaematological toxicity. Bleomycin, vincristine, cisplatin (BOP)/bleomycin, etoposide, cisplatin (BEP) represents a practicable, well-tolerated, dose intense chemotherapy regimen with significant activity in intermediate and poor prognosis MGCT.

Community based program to improve firearm storage practices in rural Alaska

OBJECTIVE

To develop and evaluate a pilot program to reduce unauthorized access to firearms by youth by distributing gun safes and trigger locks to households.

DESIGN

Pilot intervention with pre/post-evaluation design.

SETTING

Two Alaska Native villages in the Bristol Bay Health Corporation region of southwest Alaska.

SUBJECTS

Forty randomly selected households with two or more guns in the home.

INTERVENTION

Initially, a focus group of community members who owned guns was convened to receive input regarding the acceptability of the distribution procedure for the gun storage devices. One gun safe and one trigger lock were distributed to each of the selected households during December 2000. Village public safety officers assisted with the distribution of the safes and provided gun storage education to participants.

MAIN OUTCOME MEASURES

Baseline data were collected regarding household gun storage conditions at the time of device distribution. Three months after distribution, unannounced onsite home visits were conducted to identify if residents were using the gun safes and/or trigger locks.

RESULTS

All selected households had at least two guns and 28 (70%) of the 40 households owned more than two guns. At baseline, 85% of homes were found to have unlocked guns in the home and were most often found in the breezeway, bedroom, storage room, or throughout the residence. During the follow up visits, 32 (86%) of the 37 gun safes were found locked with guns inside. In contrast, only 11 (30%) of the 37 trigger locks were found to be in use.

CONCLUSIONS

This community based program demonstrated that Alaska Native gun owners accepted and used gun safes when they were installed in their homes, leading to substantial improvements in gun storage practices. Trigger locks were much less likely to be used.

Pretreatment for membrane water treatment systems: a laboratory study

The goal of the work was to determine if biological treatment of water containing soil-derived humic substances has the potential for reducing the fouling of membranes used in water treatment. Laboratory scale biological filters containing biologically active carbon or iron oxide coated sand were fed humic-laden water with or without prechlorination. This stream was split, with half being further treated by microfiltration. Treated water was assessed for total organic carbon removal and biofouling potential using a glass bead assay and membrane assay for total cell counts, fouling layer thickness, and flux reduction. A combination of these assays provided more insight than any single measurement. Compared to untreated control water, biological treatment was capable of reducing downstream fouling of membrane systems. For example, fouling layer thickness was reduced by half after biological treatment, and cell counts were reduced four- to five-fold. Biological treatment coupled with microfiltration provided the best reduction of fouling, while prechlorination did not appear to impact the process. These results suggest that biological treatment may be valuable in reducing membrane fouling while reducing the amount of disinfectants used in pretreatment.

The enactive mind, or from actions to cognition: lessons from autism

Normative-IQ individuals with autism are capable of solving explicit social cognitive problems at a level that is not matched by their ability to meet the demands of everyday social situations. The magnitude of this discrepancy is now being documented through newer techniques such as eye tracking, which allows us to see and measure how individuals with autism search for meaning when presented with naturalistic social scenes. This paper offers an approach to social cognitive development intended to address the above discrepancy, which is considered a key element for any understanding of the pathophysiology of autism. This approach, called the enactive mind (EM), originates from the emerging work on 'embodied cognitive science', a neuroscience framework that views cognition as bodily experiences accrued as a result of an organism's adaptive actions upon salient aspects of the surrounding environment. The EM approach offers a developmental hypothesis of autism in which the process of acquisition of embodied social cognition is derailed early on, as a result of reduced salience of social stimuli and concomitant enactment of socially irrelevant aspects of the environment.

In vitro identification of metabolic pathways and cytochrome P450 enzymes involved in the metabolism of etoperidone

1. In vitro studies have been carried out to investigate the metabolic pathways and identify the hepatic cytochrome P450 (CYP) enzymes involved in etoperidone (Et) metabolism. 2. Ten in vitro metabolites were profiled, quantified and tentatively identified after incubation with human hepatic S9 fractions. Et was metabolized via three metabolic pathways: (A) alkyl hydroxylation to form OH-ethyl-Et (M1); (B) phenyl hydroxylation to form OH-phenyl-Et (M2); and (C) N-dealkylation to form 1-m-chlorophenylpiperazine (mCPP, M8) and triazole propyl aldehyde (M6). Six additional metabolites were formed by further metabolism of M1, M2, M6 and M8. 3. Kinetic studies revealed that all metabolic pathways were monophasic, and the pathway leading to the formation of OH-ethyl-Et was the most efficient at eliminating the drug. On incubation with microsomes expressing individual recombinant CYPs, formation rates of M1-3 and M8 were 10-100-fold greater for CYP3A4 than that for other CYP forms. The formation of these metabolites was markedly inhibited by the CYP3A4-specific inhibitor ketoconazole, whereas other CYP-specific inhibitors did not show significant effects. In addition, the production of M1-3 and M8 was strongly correlated with CYP3A4-mediated testosterone 6beta-hydroxylase activities in 13 different human liver microsome samples. 4. Dealkylation of the major metabolite M1 to form mCPP (M8) was also investigated using microsomes containing recombinant CYP enzymes. The rate of conversion of M1 to mCPP by CYP3A4 was 503.0 +/- 3.1 pmole nmole(-1) min(-1). Metabolism of M1 to M8 by other CYP enzymes was insignificant. In addition, this metabolism in human liver microsomes was extensively inhibited by the CYP3A4 inhibitor ketoconazole, but not by other CYP-specific inhibitors. In addition, conversion of M1 to M8 was highly correlated with CYP3A4-mediated testosterone 6beta-hydroxylase activity. 5. The results strongly suggest that CYP3A4 is the predominant enzyme-metabolizing Et in humans.

Visual fixation patterns during viewing of naturalistic social situations as predictors of social competence in individuals with autism

BACKGROUND

Manifestations of core social deficits in autism are more pronounced in everyday settings than in explicit experimental tasks. To bring experimental measures in line with clinical observation, we report a novel method of quantifying atypical strategies of social monitoring in a setting that simulates the demands of daily experience. Enhanced ecological validity was intended to maximize between-group effect sizes and assess the predictive utility of experimental variables relative to outcome measures of social competence.

METHODS

While viewing social scenes, eye-tracking technology measured visual fixations in 15 cognitively able males with autism and 15 age-, sex-, and verbal IQ-matched control subjects. We reliably coded fixations on 4 regions: mouth, eyes, body, and objects. Statistical analyses compared fixation time on regions of interest between groups and correlation of fixation time with outcome measures of social competence (ie, standardized measures of daily social adjustment and degree of autistic social symptoms).

RESULTS

Significant between-group differences were obtained for all 4 regions. The best predictor of autism was reduced eye region fixation time. Fixation on mouths and objects was significantly correlated with social functioning: increased focus on mouths predicted improved social adjustment and less autistic social impairment, whereas more time on objects predicted the opposite relationship.

CONCLUSIONS

When viewing naturalistic social situations, individuals with autism demonstrate abnormal patterns of social visual pursuit consistent with reduced salience of eyes and increased salience of mouths, bodies, and objects. Fixation times on mouths and objects but not on eyes are strong predictors of degree of social competence.