Perceptions About Local ART Adherence Norms and Personal Adherence Behavior Among Adults Living with HIV in Rural Uganda

AIDS and Behavior - Although misperceived norms often drive personal health behaviors, we do not know about this phenomenon in the context of antiretroviral therapy (ART) adherence. We conducted a...     

Tandem pore domain K+‐channel TASK‐3 (KCNK9) and idiopathic absence epilepsies

Recently, the gene coding for the tandem pore domain K⁺‐channel TASK‐3 (KCNK9) has been localized to the chromosomal region 8q24. Because mutations in ion channel genes have been recognized as an important factor in the etiology of abnormal neuronal excitability, TASK‐3 is an interesting candidate gene for epilepsies linked to 8q24. We therefore performed a mutation analysis of the TASK‐3 gene in 65 patients with childhood and juvenile absence epilepsy. Only one silent nucleotide exchange (636C/T) was detected in exon 2 of the TASK‐3 coding region. No evidence for an allelic association was found between the exon 2 polymorphism and absence epilepsy. Accordingly, genetic variation of the TASK‐3 coding region does not play a major role in the etiology of idiopathic absence epilepsies. © 2002 Wiley‐Liss, Inc.     

Myokymia and neonatal epilepsy caused by a mutation in the voltage sensor of the KCNQ2 K+ channel

KCNQ2 and KCNQ3 are two homologous K(+) channel subunits that can combine to form heterotetrameric channels with properties of neuronal M channels. Loss-of-function mutations in either subunit can lead to benign familial neonatal convulsions (BFNC), a generalized, idiopathic epilepsy of the newborn. We now describe a syndrome in which BFNC is followed later in life by myokymia, involuntary contractions of skeletal muscles. All affected members of the myokymia/BFNC family carried a mutation (R207W) that neutralized a charged amino acid in the S4 voltage-sensor segment of KCNQ2. This substitution led to a shift of voltage-dependent activation of KCNQ2 and a dramatic slowing of activation upon depolarization. Myokymia is thought to result from hyperexcitability of the lower motoneuron, and indeed both KCNQ2 and KCNQ3 mRNAs were detected in the anterior horn of the spinal cord where the cells of the lower motoneurons arise. We propose that a difference in firing patterns between motoneurons and central neurons, combined with the drastically slowed voltage activation of the R207W mutant, explains why this particular KCNQ2 mutant causes myokymia in addition to BFNC.     

The new voltage gated potassium channel KCNQ5 and neonatal convulsions

In 1998, mutations in the voltage gated potassium channel gene KCNQ2 were found to be the main cause underlying the autosomal dominant inherited syndrome of benign familial neonatal convulsions (BFNC). In one BFNC family a mutation was found in an homologous gene, KCNQ3. We have now identified another brain-expressed member of this ion channel subfamily, KCNQ5, which maps to chromosome 6q14. On the genomic level KCNQ5 is composed of 14 exons, which are coding for 897 amino acid residues. Mutation analysis made KCNQ5 unlikely as a candidate gene for benign neonatal convulsions in patients with a positive family history for neonatal or early infantile seizures, but without mutations in the KCNQ2 or KCNQ3 genes.     

A new Chrna4 mutation with low penetrance in nocturnal frontal lobe epilepsy

PURPOSE: To identify and characterize the mutation(s) causing nocturnal frontal lobe epilepsy in a German extended family. METHODS: Neuronal nicotinic acetylcholine receptor (nAChR) subunit genes were screened by direct sequencing. Once a CHRNA4 mutation was identified, its biophysical and pharmacologic properties were characterized by expression experiments in Xenopus oocytes. RESULTS: We report a new CHRNA4 mutation, causing a alpha4-T265I amino acid exchange at the extracellular end of the second transmembrane domain (TM). Functional studies of alpha4-T265I revealed an increased ACh sensitivity of the mutated receptors. alpha4-T265I is associated with an unusual low penetrance of the epilepsy phenotype. Sequencing of the TM1-TM3 parts of the 1 known nAChR subunits did not support a two-locus model involving a second nAChR sequence variation. CONCLUSIONS: nAChR mutations found in familial epilepsy are not always associated with an autosomal dominant mode of inheritance. alpha4-T265I is the first nAChR allele showing a markedly reduced penetrance consistent with a major gene effect. The low penetrance of the mutation is probably caused by unknown genetic or environmental factors or both.     

Tandem pore domain K(+)-channel TASK-3 (KCNK9) and idiopathic absence epilepsies

Recently, the gene coding for the tandem pore domain K(+)-channel TASK-3 (KCNK9) has been localized to the chromosomal region 8q24. Because mutations in ion channel genes have been recognized as an important factor in the etiology of abnormal neuronal excitability, TASK-3 is an interesting candidate gene for epilepsies linked to 8q24. We therefore performed a mutation analysis of the TASK-3 gene in 65 patients with childhood and juvenile absence epilepsy. Only one silent nucleotide exchange (636C/T) was detected in exon 2 of the TASK-3 coding region. No evidence for an allelic association was found between the exon 2 polymorphism and absence epilepsy. Accordingly, genetic variation of the TASK-3 coding region does not play a major role in the etiology of idiopathic absence epilepsies.     

A splice-site mutation in GABRG2 associated with childhood absence epilepsy and febrile convulsions

CONTEXT: Missense mutations in the GABRG2 gene, which encodes the gamma 2 subunit of central nervous gamma-aminobutyric acid (GABA)(A) receptors, have recently been described in 2 families with idiopathic epilepsy. In one of these families, the affected individuals predominantly exhibited childhood absence epilepsy and febrile convulsions. OBJECTIVE: To assess the role of GABRG2 in the genetic predisposition to idiopathic absence epilepsies. DESIGN: The GABRG2 gene was screened by single-strand conformation analysis for mutations. Furthermore, a population-based association study assessing a common exon 5 polymorphism (C588T) was carried out. PATIENTS: The sample was composed of 135 patients with idiopathic absence epilepsy and 154 unrelated and ethnically matched controls. RESULTS: A point mutation (IVS6 + 2T-->G) leading to a splice-donor site mutation in intron 6 was found. The mutation, which is predicted to lead to a nonfunctional protein, cosegregates with the disease status in a family with childhood absence epilepsy and febrile convulsions. The association study did not find any significant differences in the allele and genotype frequencies of the common exon 5 polymorphism (C588T) between patients with idiopathic absence epilepsy and controls (P>.35). CONCLUSIONS: Our study identified a splice-donor-site mutation that was probably causing a nonfunctional GABRG2 subunit. This mutation occurred in heterozygosity in the affected members of a single nuclear family, exhibiting a phenotypic spectrum of childhood absence epilepsy and febrile convulsions. The GABRG2 gene seems to confer a rare rather than a frequent major susceptibility effect to common idiopathic absence epilepsy syndromes.     

Ease of marital communication and depressive symptom severity among men and women in rural Uganda: cross-sectional,whole-population study

Purpose

Depression is a major contributor to the global burden of disease. The extent to which marital communication may influence depression in contexts with little mental health support is unknown.

Methods

We conducted a whole-population study of married adult residents of eight villages in a rural region of southwestern Uganda. Depression symptom severity was measured using a modified version of the Hopkins Symptom Checklist for Depression, with > 1.75 classified as a positive screen for probable depression. Respondents were asked to report about ease of marital communication (‘never easy’, ‘easy once in a while’, ‘easy most of the time’ or ‘always easy’). Sex-stratified, multivariable Poisson regression models were fit to estimate the association between depression symptom severity and marital communication.

Results

Among 492 female and 447 male participants (response rate = 96%), 23 women and 5 men reported communication as ‘never easy’ and 154 women and 72 men reported it as ‘easy once in a while’. Reporting communication as ‘never easy’ was associated with an increased risk of probable depression among women (adjusted relative risk [ARR], 2.06; 95% confidence interval [CI], 1.08–3.93, p = 0.028) and among men (ARR, 7.10; 95% CI 1.70–29.56, p = 0.007).

Conclusion

In this whole-population study of married adults in rural Uganda, difficulty of marital communication was associated with depression symptom severity. Additional research is needed to assess whether communication training facilitated by local leaders or incorporated into couples-based services might be a novel pathway to address mental health burden.