Changes in the central nervous activity of rats treated with dimethoate in combination with other neurotoxicants in different phases of ontogenesis

Organophosphates are usually found in the environment with other pesticides and with pollutants of industrial origin can cause combined exposure involving unknown interactions between the agents. In this study, female Wistar rats were given 1/25 LD50 of dimethoate by gavage, combined with the same LD50 fractions of propoxur and cypermethrin or with arsenic (6.66 mg kg(-1)). The doses were given from day 5 to 15 of pregnancy, or that plus for the 4 weeks of lactation, or that plus 8 weeks for the male offspring after weaning. Control rats received distilled water. Electrophysiological recording was done when the male offspring reached 12 weeks of age. Spontaneous activity and evoked potentials from the somatosensory, visual and auditory cortex; and conduction velocity and absolute and relative refractory periods of the tail nerve were measured. The general trend was a shift of the spontaneous cortical activity to higher frequencies and increase in the evoked potential latency. The results showed that combined exposure to several environmental toxicants could be more harmful than the effects of each substance alone, indicating the importance of combination toxicology in modelling human effects. Furthermore, these results emphasize the importance of avoiding toxic exposures in pregnant and nursing women.     

Expression of C-type lectin receptors by subsets of dendritic cells in human skin

C-type lectins are cell surface receptors that recognize carbohydrate structures which are often part of microbial pathogens. Several of these molecules are expressed on dendritic cells and are involved in antigen uptake. Expression of C-type lectins on dendritic cells of the human skin, i.e. Langerhans cells of the epidermis and dermal dendritic cells, has been incompletely studied to date. We therefore investigated C-type lectins in situ and on dendritic cells obtained by migration from skin explants by immunofluorescence and flow cytometry. Emphasis was laid on expression patterns of DEC-205/CD205 and BDCA-2, a marker for plasmacytoid dendritic cells. Langerhans cells in situ expressed low levels of DEC-205. Expression was upregulated upon maturation in skin explant organ culture. Most dermal dendritic cells were found to be positive for DEC-205 and DC-SIGN/CD209. Few BDCA-2-expressing cells were found in most skin samples. They were located in small groups in the dermis close beneath the basement membrane. The vast majority of all types of dendritic cells in normal human skin was of immature phenotype, i.e. did not express DC-LAMP/CD208. It is concluded that normal appearing human skin harbors different subsets of dendritic cells including few scattered BDCA-2-expressing cells, presumably plasmacytoid dendritic cells, expressing variable sets of C-type lectin receptors. This may critically contribute to the capacity of the skin immune system to flexibly respond to the world of microbial pathogens.     

Follicular lymphoma

Follicular lymphoma is one of the most common indolent nodal non-Hodgkin's lymphomas. The follicular lymphoma should be differentiated from other nodal non-germinal centre derived lymphomas. Since bcl-2 gene translocation can be detected in 80-90% of the cases, it could be used for the confirmation of the diagnosis, measure of the treatment efficacy as well as for the evaluation of the prognosis and follow-up of the disease. There is no uniform therapy employed for follicular lymphoma patients. The treatment depends on the histological grade, stage, age and condition of the patients. Since disease cannot be cured by conventional dosage therapy in the vast majority of the cases, a treatment--adjusted to the condition of the patients as well as the stage and grade of the disease--ensuring the longest period and best quality of life should be selected. The authors review the questions of diagnosis and treatment, including the results of radiotherapy and chemotherapy and discuss the role of the interferon-alpha, purine analogues, monoclonal antibodies and high-dose therapy.     

Radionuclide cardangiography as non-invasive assessment in coronary heart disease (author's transl)]

The method of radionuclide cardangiography (RNCA) has become a well-established method amongst non-invasive assessments in coronary heart disease (CHD). By means of RNCA the most important parameters of left ventricular function, viz. ejection fraction (EF) and wall motion (WM), can be determined very exactly. The first bolus pass method (FBP), which allows satisfactory separation between right and left heart, enables the additional determination of EF distribution, stroke volume (SV) and SV distribution. This method requires the technical necessity of a multicrystal gamma camera. Special nuclear medicine characteristics have been worked out for different groups of CHD. EF and WM show typical signs of angina pectoris, caused by exercise correlating with reduced perfusion in the referring section of WM. While these changes may be reversible after nitrate administration, pathological myocardial function caused by acute myocardial infarction (AMI) or manifest heart failure is not reversed by nitroglycerine. Typical findings were seen in the course of AMI: initial decrease in global EF and diffuse (multilocated) asynergies in the left ventricular wall; in the second week possible start of recovery, including regression of dyskinesia to akinesia at the end of hospitalization. Especially in the early phase of AMI it was demonstrated that FBP--as a non-invasive technique--gives high information quality which is unequalled by other comparable methods. Therefore, the described method of FBP should be classified as very useful and effective in clinical cardiology.     

A Phase 2 Trial of Sunitinib in Patients with Advanced Non–clear Cell Renal Cell Carcinoma

Background

Sunitinib is a standard-of-care treatment in advanced clear cell renal cell carcinoma (ccRCC). Retrospective and expanded access data suggest sunitinib has activity in advanced non–clear cell renal cell carcinoma (nccRCC).

Objective

To prospectively determine the clinical efficacy and safety of sunitinib in patients with advanced nccRCC.

Design, setting, and participants

This is a single-arm phase 2 trial with a two-stage design. Eligibility criteria included pathologically confirmed nccRCC or ccRCC with ≥20% sarcomatoid histology, performance status 0–2, measurable disease, a maximum of two prior systemic therapies, and no prior treatment with tyrosine kinase inhibitors directed against the vascular endothelial growth factor receptors.

Intervention

Patients received sunitinib 50 mg daily on a 4-wk on, 2-wk off schedule.

Outcome measurements and statistical analysis

Primary end points were objective response rate (ORR) and progression-free survival (PFS). Secondary end points were safety and overall survival (OS).

Results and limitations

Fifty-seven patients were eligible (nccRCC histology: papillary, 27; chromophobe, 5; unclassified, 8; collecting duct or medullary carcinoma, 6; sarcomatoid, 7; and others, 4). Median PFS for 55 evaluable patients was 2.7 mo (95% confidence interval [CI], 1.4–5.4). Two patients with chromophobe and one patient with unclassified histology had a confirmed partial response (5% ORR). Median PFS for patients with papillary histology was 1.6 mo (95% CI, 1.4–5.4). Median PFS for patients with chromophobe histology was 12.7 mo (95% CI, 8.5–NA). Median OS for all patients was 16.8 mo (95% CI, 10.7–26.3). Treatment-emergent adverse events were consistent with sunitinib's mechanism of action. The nonrandomized design and small number of patients are limitations of this study.

Conclusions

The differential response of chromophobe histology to sunitinib suggests a therapeutically relevant biological heterogeneity exists within nccRCC. The low ORR and short PFS with sunitinib in the other nccRCC subtypes underscore the need to enroll patients with these diverse tumors in clinical trials.     

A novel virtual reality-based theory of mind intervention for outpatients with schizophrenia: A proof-of-concept pilot study

Schizophrenia is a severe and highly disabling mental illness. Although several pharmacological solutions are available to alleviate symptoms of schizophrenia, they do not seem to provide solution for accompanying social dysfunctions. To handle this unmet clinical need, many innovative interventions have been developed recently. Considering the promising results on this field and the development trend, characterized by the growing proportion of included interactive technology, our research team developed a novel virtual reality (VR)-based targeted theory of mind (ToM) intervention (VR-ToMIS) for stable outpatients with schizophrenia. VR-ToMIS is a nine-session long structured and individualized method that uses cognitive and behavioural therapeutic techniques in an immersive VR environment. Our study was a randomized, controlled pilot study. Twenty-one patients have been recruited and randomly allocated to either VR-ToMIS or passive VR condition. Patients assigned to passive VR condition could use the same VR software as the VR-ToMIS group, but without any interventions. Effects on psychiatric symptoms, neurocognitive and social cognitive functions, pragmatic language skills and quality of life were evaluated by using analysis of covariance. According to our results, VR-ToMIS was associated with improvements in negative symptoms, in one neurocognitive field (immediate memory), ToM and pragmatic language skills, but no significant change in quality of life scores was detected. Significant changes in VR-ToMIS group were associated with moderate to large therapeutic effects (η_p² = .24–.46, φ = .55–.67). On the background of the presented pilot results, VR-ToMIS is concluded to be feasible and tolerable.     

Conflict Detection in a Sequential Decision Task Is Associated with Increased Cortico-Subthalamic Coherence and Prolonged Subthalamic Oscillatory Response in the β Band

Making accurate decisions often involves the integration of current and past evidence. Here, we examine the neural correlates of conflict and evidence integration during sequential decision-making. Female and male human patients implanted with deep-brain stimulation (DBS) electrodes and age-matched and gender-matched healthy controls performed an expanded judgment task, in which they were free to choose how many cues to sample. Behaviorally, we found that while patients sampled numerically more cues, they were less able to integrate evidence and showed suboptimal performance. Using recordings of magnetoencephalography (MEG) and local field potentials (LFPs; in patients) in the subthalamic nucleus (STN), we found that β oscillations signaled conflict between cues within a sequence. Following cues that differed from previous cues, β power in the STN and cortex first decreased and then increased. Importantly, the conflict signal in the STN outlasted the cortical one, carrying over to the next cue in the sequence. Furthermore, after a conflict, there was an increase in coherence between the dorsal premotor cortex and STN in the β band. These results extend our understanding of cortico-subcortical dynamics of conflict processing, and do so in a context where evidence must be accumulated in discrete steps, much like in real life. Thus, the present work leads to a more nuanced picture of conflict monitoring systems in the brain and potential changes because of disease.SIGNIFICANCE STATEMENT Decision-making often involves the integration of multiple pieces of information over time to make accurate predictions. We simultaneously recorded whole-head magnetoencephalography (MEG) and local field potentials (LFPs) from the human subthalamic nucleus (STN) in a novel task which required integrating sequentially presented pieces of evidence. Our key finding is prolonged β oscillations in the STN, with a concurrent increase in communication with frontal cortex, when presented with conflicting information. These neural effects reflect the behavioral profile of reduced tendency to respond after conflict, as well as relate to suboptimal cue integration in patients, which may be directly linked to clinically reported side-effects of deep-brain stimulation (DBS) such as impaired decision-making and impulsivity.     

G970R‐CFTR Mutation (c.2908G>C) Results Predominantly in a Splicing Defect

In previous work, participants with a G970R mutation in cystic fibrosis transmembrane conductance regulator (CFTR) (c.2908G>C) had numerically lower sweat chloride responses during ivacaftor treatment than participants with other CFTR gating mutations. The objective of this substudy was to characterize the molecular defect of the G970R mutation in vitro and assess the benefit of ivacaftor in participants with this mutation. This substudy assessed sweat chloride, spirometry findings, and nasal potential difference on and off ivacaftor treatment in three participants with a G970R/F508del genotype. Intestinal organoids derived from rectal biopsy specimens were used to assess ivacaftor response ex vivo and conduct messenger RNA splice and protein analyses. No consistent or meaningful trends were observed between on‐treatment and off‐treatment clinical assessments. Organoids did not respond to ivacaftor in forskolin‐induced swelling assays; no mature CFTR protein was detected in Western blots. Organoid RNA analysis demonstrated that 3 novel splice variants were created by G970R‐CFTR: exon 17 truncation, exons 13–15 and 17 skipping, and intron 17 retention. Functional and molecular analyses indicated that the c.2908G>C mutation caused a cryptic splicing defect. Organoids lacked an ex vivo response with ivacaftor and supported identification of the mechanism underlying the CFTR defect caused by c.2908G>C. Analysis of CFTR mutations indicated that cryptic splicing was a rare cause of mutation misclassification in engineered cell lines. This substudy used organoids as an alternative in vitro model for mutations, such as cryptic splice mutations that cannot be fully assessed using cDNA expressed in recombinant cell systems.

Study Highlights

• WHAT IS THE CURRENT KNOWLEDGE ON THE TOPIC?

☑ Participants with the G970R mutation in the CFTR gene have lower sweat chloride responses to ivacaftor treatment than do participants with G551D or other non–G551D‐CFTR gating mutations.

• WHAT QUESTION DID THIS STUDY ADDRESS?

☑ This substudy characterized the molecular defect of the G970R‐CFTR mutation in vitro and assessed the benefit of ivacaftor in participants with this mutation.

• WHAT DOES THIS STUDY ADD TO OUR KNOWLEDGE?

☑ The functional and molecular analyses revealed that the G970R‐CFTR mutation is not responsive to ivacaftor treatment and identified the mechanism of the CFTR defect as a cryptic splicing defect.

• HOW MIGHT THIS CHANGE CLINICAL PHARMACOLOGY OR TRANSLATIONAL SCIENCE?

☑ For mutations that cannot be fully assessed using recombinant cell systems, such as cryptic splicing defects, organoid in vitro assessments and RNA analyses can be used as alternatives to characterize mutations.

Cystic fibrosis (CF) is an autosomal recessive hereditary disease caused by mutations in the CF transmembrane conductance regulator (CFTR) gene that result in decreased quantity and/or function of the CFTR protein. ¹ , ² The CFTR protein is an epithelial chloride channel aiding in the regulation of salt and fluid absorption and secretion that is located in the epithelia of multiple organs, including the lungs, pancreas, intestinal tract, liver, and vas deferens. ³ , ⁴ , ⁵ , ⁶ CF is a multisystemic disease with clinical manifestations, including lung function decline, chronic airway infections, pancreatic insufficiency, and malnutrition. ⁷ Ivacaftor (Kalydeco^(R); Vertex Pharmaceuticals, Boston, MA) is a CFTR modulator that increases chloride transport by potentiating the channel open probability (P₀ (or gating)) of the CFTR protein at the epithelial cell surface. ⁸ Currently, ivacaftor is indicated in the United States for people aged ≥ 4 months with CF with ≥ 1 CFTR mutation that is responsive to ivacaftor based on clinical and/or in vitro assay data ⁹ ; the approved genotypes and ages vary in other regions. ¹⁰ , ¹¹ , ¹² In clinical studies of people with CF with eligible genotypes, ivacaftor treatment has been shown to achieve improvements in CFTR function, lung function, risk of pulmonary exacerbations, pancreatic function, and nutritional status. ¹³ , ¹⁴ , ¹⁵ , ¹⁶ , ¹⁷ Among > 340 known CF‐causing CFTR mutations identified, 10 have historically been classified as class III mutations that result in severe defects in CFTR channel gating: G551D, G178R, S549N, S549R, G551S, G970R, G1244E, S1251N, S1255P, and G1349D. ² , ¹⁸ , ¹⁹ , ²⁰ , ²¹ In Fischer rat thyroid (FRT) cells engineered to individually express complementary DNAs (cDNAs) that express CFTR proteins coding each of these mutations, chloride transport as determined by electrophysiological studies was < 5% of normal CFTR, despite the presence of mature CFTR protein at levels similar to those of normal CFTR. Ivacaftor increased the channel P₀ of these 10 CFTR forms and caused an increase in CFTR‐mediated chloride transport to levels equivalent to > 10% above baseline. These in vitro data supported investigation of the potential clinical benefit with ivacaftor in people with CF with severe gating mutations. ⁸ In a clinical study of ivacaftor in participants with CF who had a non‐G551D severe gating mutation, participants with a G970R‐CFTR mutation had a numerically lower treatment response than participants with the other gating mutations. ¹⁴ Given this result, the molecular defect of the G970R mutation was further evaluated as part of the completed open‐label extension study KONTINUE. ¹⁵ Organoids, a cell culture technology platform, ²² enabled generation of an in vitro model from each participant that expresses the CFTR protein based on the genomic DNA rather than on a cDNA construct. These organoids were used for in vitro functional CFTR experiments to evaluate the response with ivacaftor and for further mechanistic studies to help clarify the range of functional defects caused by the G970R mutation.