Paper-based microchip electrophoresis for point-of-care hemoglobin testing

Nearly 7% of the world's population live with a hemoglobin variant. Hemoglobins S, C, and E are the most common and significant hemoglobin variants worldwide. Sickle cell disease, caused by hemoglobin S, is highly prevalent in sub-Saharan Africa and in tribal populations of Central India. Hemoglobin C is common in West Africa, and hemoglobin E is common in Southeast Asia. Screening for significant hemoglobin disorders is not currently feasible in many low-income countries with the high disease burden. Lack of early diagnosis leads to preventable high morbidity and mortality in children born with hemoglobin variants in low-resource settings. Here, we describe HemeChip, the first miniaturized, paper-based, microchip electrophoresis platform for identifying the most common hemoglobin variants easily and affordably at the point-of-care in low-resource settings. HemeChip test works with a drop of blood. HemeChip system guides the user step-by-step through the test procedure with animated on-screen instructions. Hemoglobin identification and quantification is automatically performed, and hemoglobin types and percentages are displayed in an easily understandable, objective way. We show the feasibility and high accuracy of HemeChip via testing 768 subjects by clinical sites in the United States, Central India, sub-Saharan Africa, and Southeast Asia. Validation studies include hemoglobin E testing in Bangkok, Thailand, and hemoglobin S testing in Chhattisgarh, India, and in Kano, Nigeria, where the sickle cell disease burden is the highest in the world. Tests were performed by local users, including healthcare workers and clinical laboratory personnel. Study design, methods, and results are presented according to the Standards for Reporting Diagnostic Accuracy (STARD). HemeChip correctly identified all subjects with hemoglobin S, C, and E variants with 100% sensitivity, and displayed an overall diagnostic accuracy of 98.4% in comparison to reference standard methods. HemeChip is a versatile, mass-producible microchip electrophoresis platform that addresses a major unmet need of decentralized hemoglobin analysis in resource-limited settings.

Linkage analysis of attention deficit hyperactivity disorder

Results of behavioral genetic and molecular genetic studies have converged to suggest that both genes contribute to the development of ADHD. Although prior linkage studies have produced intriguing results, their results have been inconsistent, with no clear pattern of results emerging across studies. We genotyped 5,980 SNPs across the genome in 1,187 individuals from families with children diagnosed with ADHD. We then performed two nonparametric linkage analyses on ADHD families: (1) an affected sibling pair linkage analysis on 217 families with 601 siblings diagnosed with ADHD and (2) a variance components linkage analysis using the number of ADHD symptoms as the phenotype on 260 families with 1,100 phenotyped siblings. The affection status linkage analysis had a maximum LOD score of 1.85 on chromosome 8 at 54.2 cM. The maximum LOD score in the variance components linkage analysis was 0.8 on chromosome 8 at 93.4 cM. The absence of regions of significant or suggestive linkage in these data suggest that there are no genes of large effect contributing to the ADHD phenotype.

Ethnic Differences in Attributions and Treatment Expectancies for Adolescent Depression

Studies suggest that ethnicity and socioeconomic factors may relate to differences in treatment expectancies and the attributions made for emotional or behavioral problems. We examined ethnic differences in (1) parents' attributions about the causes of adolescent behavioral and emotional problems and (2) treatment expectancies among 236 adolescent participants who enrolled in a 36-week randomized controlled trial for depression. Controlling for education and income, European American parents were more likely to endorse beliefs reflecting physical causes of depression than African American parents. There were no ethnic differences for beliefs reflecting external, familial, or community factors. Ethnic differences were observed in the treatment expectancies reported by parents, but not adolescents, with African American parents more likely than European Americans and Other minorities to endorse positive expectations for CBT. These findings may have implications for understanding discrepancies in mental health service use.

Antidepressant prescribing practices for the treatment of children and adolescents

OBJECTIVE

This study evaluates pediatric antidepressant prescribing practices of Nebraska clinicians.

METHODS

Surveys were sent in July, 2005, to 1,521 prescribing clinicians throughout Nebraska to assess pediatric antidepressant use along with any practice changes following the U.S. Food and Drug Administration (FDA) "black box" warning issued in October, 2004.

RESULTS

Over half (n = 866) of the clinicians responded to the survey, of which 96.8% reported awareness of the FDA "black box" warning. Of the respondents, 76.9% (n = 666) were prescribing antidepressants to children and/or adolescents. Clinicians reported decreased prescribing frequency for both children (15.5%) and adolescents (36.6%), with 36% having increased referrals to specialists. While 31.9% reported seeing patients more frequently upon initiation of antidepressants, only 7.5% reported weekly visits for the first month of treatment, as recommended by the FDA. Over one fifth (21.9%) reported a caregiver or patient had refused antidepressant medication treatment due to the FDA's warning.

CONCLUSION

Clinicians in Nebraska report changes in clinical practice due to the issuance of the FDA "black box" warning, with a decrease in prescribing antidepressants to pediatric patients and an increase in referrals to specialists. Although awareness of the FDA's warning was evident among clinicians and patients, adherence to recommended guidelines was low.

A manual-based intervention to address clinical crises and retain patients in the Treatment of Adolescents With Depression Study (TADS)

OBJECTIVE

To describe a manual-based intervention to address clinical crises and retain participants in the Treatment for Adolescents With Depression Study (TADS).

METHOD

The use of adjunct services for attrition prevention (ASAP) is described for adolescents (ages 12-17 years) during the 12-week acute treatment in TADS, from 2000 to 2003. Logistic regression, controlling for site, was used to predict use.

RESULTS

Of 439 enrolled participants, 17.8% (n = 78) used ASAP primarily for suicidality or worsening of depression. Of these, 46.2% continued in their assigned treatment through week 12, 47.4% received out-of-protocol treatment but continued participating in assessments, and 10.3% withdrew consent, including 3 who terminated treatment and withdrew consent on the same date. ASAP use did not differ between treatments (p =.97) and typically occurred early in treatment. At the end of the 12 weeks, 37.2% of participants using ASAP remained in their assigned treatment, although 80.8% continued participating in assessments. ASAP was associated with, at baseline, a higher severity of depression (p <.01), substance use (p <.01), and precontemplation level of change (p <.02).

CONCLUSIONS

ASAP may be useful to retain adolescent participants and as a safety intervention in placebo-controlled trials. In clinical practice ASAP-like procedures may be useful to encourage adherence in patients engaging in long-term treatment. Clinical trial registration information-URL: http://www.clinicaltrials.gov. Unique identifier: NCT00006286.