Pyrosequencing, a high-throughput method for detecting single nucleotide polymorphisms in the dihydrofolate reductase and dihydropteroate synthetase genes of Plasmodium falciparum

A pyrosequencing protocol was developed as a rapid and reliable method to identify the mutations of the dhfr and dhps genes of Plasmodium falciparum that are associated with antifolate resistance. The accuracy and specificity of this method were tested using six laboratory-cultured P. falciparum isolates harboring known single nucleotide polymorphisms (SNPs) in the genes dhfr (codons 50, 51, 59, 108, and 164) and dhps (codons 436, 437, 540, 581, and 613). The lowest threshold for detection of all the SNPs tested by pyrosequencing was the equivalent of two to four parasite genomes. Also, this method was highly specific for P. falciparum, as it did not amplify any DNA products from the other species of human malaria parasites. We also mixed wild-type and mutant-type parasite DNAs in various proportions to determine how pyrosequencing, restriction fragment length polymorphism (RFLP), and direct conventional sequencing (for dhfr) compared with each other in detecting different SNPs in the mixture. In general, pyrosequencing and RFLP showed comparable sensitivities in detecting most of the SNPs in dhfr except for the 164L mutation, which required at least twice the amount of DNA for pyroseqencing as for RFLP. For detecting SNPs in dhps, pyrosequencing was slightly more sensitive than RFLP and direct sequencing. Overall, pyrosequencing was faster and less expensive than either RFLP or direct sequencing. Thus, pyrosequencing is a practical alternative method that can be used in a high-throughput format for molecular surveillance of antimalarial-drug resistance.     

Anhedonia Following Early-Life Adversity Involves Aberrant Interaction of Reward and Anxiety Circuits and Is Reversed by Partial Silencing of Amygdala Corticotropin-Releasing Hormone Gene

Background

Anhedonia, the diminished ability to experience pleasure, is an important dimensional entity linked to depression, schizophrenia, and other emotional disorders, but its origins and mechanisms are poorly understood. We have previously identified anhedonia, manifest as decreased sucrose preference and social play, in adolescent male rats that experienced chronic early-life adversity/stress (CES). Here we probed the molecular, cellular, and circuit processes underlying CES-induced anhedonia and tested them mechanistically.

Developing Alternative Stories with Partners of Illicit Substance Users

The needs of partners of illicit substance users (ISU) in recovery have traditionally been left out of the treatment process. Dominant social discourses concerning partners’ behaviors typically constrain and marginalize the spectrum of their experiences beyond illicit substance use. This article discusses prevailing dominant discourses in the field that conceptualize society’s perception of partners of illicit substance users. Reaching beyond the scope of dominant approaches, Narrative Therapy Practices can help partners of illicit substance users in early recovery help create alternative stories, derive new meanings, and develop personal agency in addressing their problems. Considering the ideas expressed in this article, this article bridges the current treatment gap by opening space for reconfiguring understanding of partners’ experiences. In order to help bring counselors awareness and generate new conversations that will attend to the needs of partners in recovery. It will also promote a greater understanding of narrative practices with groups as a means to facilitate an environment that will help partners of those in early recovery cope with the impact of illicit substance use on their lives.

This article contributes toward future development of practices to assist partners of illicit substance users (ISU) in early recovery.     

An investigation of antistreptococcal antibody responses in guttate psoriasis

In two-thirds of patients with guttate psoriasis (GP), there is good evidence that the eruption is triggered by a streptococcal throat infection. We attempted to determine if a specific epitope of the bacterial pathogen was associated with the humoral immune response in GP patients. Antibody titres against beta-haemolytic streptococci (BHS) extracts in sera from 14 patients with GP, 10 healthy controls and 10 chronic plaque psoriasis (CPP) patients were determined by ELISA. Antibody BHS reactivity was investigated using immunoblotting, followed by epitope mapping using peptide-phage display. The highest GP antibody titres (10,000-25,000) were found in sera that had a matching streptococcal isolate, three sera had high (5,000-12,500) and seven had raised titres (500-5,000). In the healthy control group, three had relatively high and seven lower titres. All the CPP sera had very low titres (<500). In the immunoblots, three major bands were recognised by all the GP sera, and, to a lesser extent, by four healthy controls. No GP-specific protein was identified. Epitope mapping identified 10 phage clones that specifically bound 2 or 3 GP sera, displaying five different peptide sequences that were not streptococcal in origin. These findings suggest that the antigen specificity of the humoral response to BHS in GP does not differ from that of non-psoriatic individuals.     

The Effect of an Education Module to Reduce Weight Bias among Medical Centers Employees: A Randomized Controlled Trial

IntroductionWeight bias, stigma, and discrimination are common among healthcare professionals. We aimed to evaluate whether an online education module affects weight bias and knowledge about obesity in a private medical center setting.MethodsAn open-label randomized controlled trial was conducted among all employees of a chain of private medical centers in Israel (n = 3,290). Employees who confirmed their consent to participate in the study were randomized into intervention or control (i.e., “no intervention”) arms. The study intervention was an online 15-min educational module that included obesity, weight bias, stigma, and discrimination information. Questionnaires on Anti-Fat Attitudes (AFA), fat-phobia scale (F-scale), and beliefs about the causes of obesity were answered at baseline (i.e., right before the intervention), 7 days, and 30 days post-intervention.ResultsA total of 506, 230, and 145 employees responded to the baseline, 7-day, and 30-day post-intervention questionnaires, respectively. Mean participant age was 43.3 ± 11.6 years, 84.6% were women, and 67.4% held an academic degree. Mean F-scale scores and percentage of participants with above-average fat-phobic attitudes (≥3.6) significantly decreased only within the intervention group over time (p ≤ 0.042). However, no significant differences between groups over time were observed for AFA scores or factors beliefs to cause obesity.ConclusionsA single exposure to an online education module on weight bias and knowledge about obesity may confer only a modest short-term improvement in medical center employees'' fat-phobic attitudes toward people with obesity. Future studies should examine if reexposure to such intervention could impact weight bias, stigma, and discrimination among medical center staff in the long-term.