Hemizygous variants in protein phosphatase 1 regulatory subunit 3F (PPP1R3F) are associated with a neurodevelopmental disorder characterized by developmental delay, intellectual disability and autistic features

Protein phosphatase 1 regulatory subunit 3F (PPP1R3F) is a member of the glycogen targeting subunits (GTSs), which belong to the large group of regulatory subunits of protein phosphatase 1 (PP1), a major eukaryotic serine/threonine protein phosphatase that regulates diverse cellular processes. Here, we describe the identification of hemizygous variants in PPP1R3F associated with a novel X-linked recessive neurodevelopmental disorder in 13 unrelated individuals. This disorder is characterized by developmental delay, mild intellectual disability, neurobehavioral issues such as autism spectrum disorder, seizures and other neurological findings including tone, gait and cerebellar abnormalities. PPP1R3F variants segregated with disease in affected hemizygous males that inherited the variants from their heterozygous carrier mothers. We show that PPP1R3F is predominantly expressed in brain astrocytes and localizes to the endoplasmic reticulum in cells. Glycogen content in PPP1R3F knockout astrocytoma cells appears to be more sensitive to fluxes in extracellular glucose levels than in wild-type cells, suggesting that PPP1R3F functions in maintaining steady brain glycogen levels under changing glucose conditions. We performed functional studies on nine of the identified variants and observed defects in PP1 binding, protein stability, subcellular localization and regulation of glycogen metabolism in most of them. Collectively, the genetic and molecular data indicate that deleterious variants in PPP1R3F are associated with a new X-linked disorder of glycogen metabolism, highlighting the critical role of GTSs in neurological development. This research expands our understanding of neurodevelopmental disorders and the role of PP1 in brain development and proper function.

Open science in play and in tension with patent protections

The open science (OS) movement has garnered increasing support in academia alongside continued financial and reputational incentives to obtain intellectual property (IP) protections over research outputs. Here, we explore stakeholder perspectives about intersections between OS and IP to inform the development of institutional OS guidelines for the neurosciences in Canada. We held six focus groups and three interviews with 29 faculty members from a major research and clinical center in Canada. The semi-structured interview guide probed perspectives on the respective roles of patents and OS in neuroscience-related research. We applied thematic content analysis to the transcript data, and extracted 12 major themes and 30 subthemes. Participants perceived a conflict between OS ideologies and the inherently restrictive nature of patents, and highlighted the importance of autonomy, justice, and respectful, culturally safe research practices in any future adoption of OS. Overall, the data suggest that a hybrid OS-IP policy model supported by local expertise may be best suited to meet the priorities and values of the community while mitigating perceived threats. This model includes expanded education about patenting, incentivized data sharing and collaboration, and tangible resources to support implementation of OS that includes skilled support in digital research infrastructures.

0128 Mild Upper Airway Obstruction Leads to Increased Energy Intake and Growth Retardation that Persists After the Obstruction Removal

Introduction

Whereas pediatric obstructive sleep apnea may cause insufficient body weight gain and growth retardation, in some studies, metabolic syndrome and obesity were observed. Interestingly, treatment by adenotonsillectomy can lead to accelerated weight gain by an unclear mechanism. Here, we explored the effects of moderate upper airway obstruction (AO) and mild AO (mAO) and its removal (OR) on ventilation, resting energy expenditure (REE), food intake and growth during the diurnal cycle, from weaning to adulthood.

Methods

The trachea of 22-day-old rats was surgically narrowed to generate AO, mAO, and OR was performed after two weeks on mAO animals. Minute ventilation was recorded by whole body plethysmography and diurnal food intake, and REE was explored with metabolic cages 12 weeks post surgery.

Results

Following tracheal narrowing, inspiratory swings in esophageal pressure increased by 177% (p<0.01) and 36% (p<0.01) in AO and mAO rats, respectively, and was similar to the controls in the OR group. REE (Kcal/h/kg) was 3.7±0.1, 5.7±0.12 (p<0.01), 4.1±0.08 (p<0.01), and 3.6±0.15 in the control, AO, mAO, and OR groups, respectively. Increased EE in the AO and mAO groups was associated with up-regulation of ventilation by 133% and 56%, respectively (p<0.01). In all groups, energy intake (EE) was higher during a 12 h active period compared to a sleep period (p<0.01). EE during the lights on of AO and mAO animals increased by 136 % and 126%, respectively, and was similar to the control in the OR group. Active period EE increased by 19% in both obstructed groups (p<0.01). Active period EE was 16.7 % higher in the OR group despite the normalization of ventilation and tracheal diameter to the control value. Increased REE was associated with hindrance of bone elongation (p<0.01), and OR partially improved growth.

Conclusion

The need to maintain respiratory homeostasis during upper airway obstruction was associated with a persistent increase in energy intake. Surgical intervention may not be sufficient to correct the energy intake elevation, and endocrine regulation of feeding and growth may have greater impacts post intervention.

Support

This study was supported by the Israel Science Foundation grant no. 164/2018

Neurophysiological evidence of preserved connectivity in tuber tissue

We present a case of preserved corticospinal connectivity in a cortical tuber, in a 10 year-old boy with intractable epilepsy and tuberous sclerosis complex (TSC). The patient had multiple subcortical tubers, one of which was located in the right central sulcus. In preparation for epilepsy surgery, motor mapping, by neuronavigated transcranial magnetic stimulation (nTMS) coupled with surface electromyography (EMG) was performed to locate the primary motor cortical areas. The resulting functional motor map revealed expected corticospinal connectivity in the left precentral gyrus. Surprisingly, robust contralateral deltoid and tibialis anterior motor evoked potentials (MEPs) were also elicited with direct stimulation of the cortical tuber in the right central sulcus. MRI with diffusion tensor imaging (DTI) tractography confirmed corticospinal fibers originating in the tuber. As there are no current reports of preserved connectivity between a cortical tuber and the corticospinal tract, this case serves to highlight the functional interdigitation of tuber and eloquent cortex. Our case also illustrates the widening spectrum of neuropathological abnormality in TSC that is becoming apparent with modern MRI methodology. Finally, our finding underscores the need for further study of preserved function in tuber tissue during presurgical workup in patients with TSC.

Huperzine A as a neuroprotective and antiepileptic drug: a review of preclinical research

Huperzine A (HupA) is an acetylcholinesterase (AChE) inhibitor extracted from Huperzia Serrata, a firmoss, which has been used for various diseases in traditional Chinese medicine for fever and inflammation. More recently, it has been used in Alzheimer's disease and other forms of dementia with a presumed mechanism of action via central nicotinic and muscarinic receptors. HupA is marketed as a dietary supplement in the U.S. This article reviews newly proposed neuroprotective and anticonvulsant HupA properties based on animal studies. HupA exerts its effects mainly via α7nAChRs and α4β2nAChRs, thereby producing a potent anti-inflammatory response by decreasing IL-1β, TNF-α protein expression, and suppressing transcriptional activation of NF-κB signaling. Thus, it provides protection from excitotoxicity and neuronal death as well as increase in GABAergic transmission associated with anticonvulsant activity.

H-coil repetitive transcranial magnetic stimulation for treatment of temporal lobe epilepsy: A case report

Low frequency repetitive TMS (rTMS) of a cortical seizure focus is emerging as an antiepileptic treatment. While conventional rTMS stimulators activate only superficial cortical areas, reaching deep epileptic foci, for example in temporal lobe epilepsy (TLE), is possible using specially designed H-coils. We report the results of rTMS in a young adult with pharmacoresistant bilateral TLE who underwent three courses (of 10, 15, and 30 daily sessions) of unilateral rTMS over the hemisphere from which seizures originated most often. Seizure frequency was assessed before and after each block of rTMS sessions, as was the tolerability of the procedure. Seizure frequency declined significantly, by 50 to 70% following each rTMS course. All sessions were well-tolerated.

Rasmussen's encephalitis presenting as focal cortical dysplasia

Rasmussen's encephalitis is a rare syndrome characterized by intractable seizures, often associated with epilepsia partialis continua and symptoms of progressive hemispheric dysfunction. Seizures are usually the hallmark of presentation, but antiepileptic drug treatment fails in most patients and is ineffective against epilepsia partialis continua, which often requires surgical intervention. Co-occurrence of focal cortical dysplasia has only rarely been described and may have implications regarding pathophysiology and management. We describe a rare case of dual pathology of Rasmussen's encephalitis presenting as a focal cortical dysplasia (FCD) and discuss the literature on this topic.

Early thalamic lesions in patients with sleep-potentiated epileptiform activity

OBJECTIVE

To compare the prevalence and type of early developmental lesions in patients with a clinical presentation consistent with electrical status epilepticus in sleep either with or without prominent sleep-potentiated epileptiform activity (PSPEA).

METHODS

We performed a case-control study and enrolled patients with 1) clinical features consistent with electrical status epilepticus in sleep, 2) ≥1 brain MRI scan, and 3) ≥1 overnight EEG recording. We quantified epileptiform activity using spike percentage, the percentage of 1-second bins in the EEG tracing containing at least 1 spike. PSPEA was present when spike percentage during non-REM sleep was ≥50% than spike percentage during wakefulness.

RESULTS

One hundred patients with PSPEA (cases) and 47 patients without PSPEA (controls) met the inclusion criteria during a 14-year period. Both groups were comparable in terms of clinical and epidemiologic features. Early developmental lesions were more frequent in cases (48% vs 19.2%, p = 0.002). Thalamic lesions were more frequent in cases (14% vs 2.1%, p = 0.037). The main types of early developmental lesions found in cases were vascular lesions (14%), periventricular leukomalacia (9%), and malformation of cortical development (5%). Vascular lesions were the only type of early developmental lesions that were more frequent in cases (14% vs 0%, p = 0.005).

CONCLUSIONS

Patients with PSPEA have a higher frequency of early developmental lesions and thalamic lesions than a comparable population of patients without PSPEA. Vascular lesions were the type of early developmental lesions most related to PSPEA.

Cytokeratin immunoreactivity of intestinal metaplasia at normal oesophagogastric junction indicates its aetiology

BACKGROUND AND AIMS

Cytokeratin (CK) 7 and 20 patterns are specific for long and short segments of Barrett's oesophagus but their use has not been assessed in intestinal metaplasia arising in macroscopically normal gastro-oesophageal junction (GOJ).

PATIENTS AND METHODS

This study was carried out in a large prospective series of 254 patients who underwent upper endoscopy, had normal gastro-oesophageal anatomy, and who had biopsies of the antrum, fundus, cardia, GOJ, and lower oesophagus. Intestinal metaplasia of the GOJ was typed by histochemistry with high iron diamine-alcian blue staining and by immunohistochemistry using CK7 and CK20 antibodies. Results were correlated with clinical, endoscopic, and pathological data.

RESULTS

Sixty (23.6%) of our patients presenting with a normal GOJ had intestinal metaplasia. The CK7/CK20 pattern identified two groups of patients: one highly correlated with Barrett's and the other with characteristics of Helicobacter pylori gastritis. The Barrett's type CK7/CK20 pattern was related to a high frequency of gastro-oesophageal reflux symptoms (p<0.02) and normal endoscopic appearance of the stomach (p<0.03). In contrast, the gastric type CK7/CK20 pattern was linked to atrophic (p<0.02) or erythematous (p<0.05) appearance of the stomach (p<0.03), high frequency of H pylori infection (p<0.04), antral inflammation (p<0.006) with atrophy (p<0.02), and intestinal metaplasia (p<0.02).

CONCLUSION

In patients presenting with intestinal metaplasia in normal appearing GOJ, the cytokeratin pattern identifies two groups of patients, one with features identical to those of long segment Barrett's oesophagus and one with features seen in H pylori gastritis. These data may be used by clinicians and should result in improved endoscopic surveillance strategies targeted specifically at patients at increased risk of Barrett's oesophagus and thus cancer.

Parallel instabilities of long-term potentiation, place cells, and learning caused by decreased protein kinase A activity

To further elucidate the links among synaptic plasticity, hippocampal place cells, and spatial memory, place cells were recorded from wild-type mice and transgenic "R(AB)" mice with reduced forebrain protein kinase A (PKA) activity after introduction into a novel environment. Place cells in both strains were similar during the first exposure and were equally stable for recording sessions separated by 1 hr. Place cell stability in wild-type mice was unchanged for sessions separated by 24 hr but was reduced in R(AB) mice over the longer interval. This stability pattern parallels both the reduced late-phase long-term potentiation in hippocampal slices from R(AB) mice and the amnesia for context fear conditioning seen in R(AB) mice 24 but not 1 hr after training. The similar time courses of synaptic, network, and behavioral instability suggest that the genetic reduction of PKA activity is responsible for the defects at each level and support the idea that hippocampal synaptic plasticity is important in spatial memory.

Variable place-cell coupling to a continuously viewed stimulus: evidence that the hippocampus acts as a perceptual system

A key feature of perception is that the interpretation of a single, continuously available stimulus can change from time to time. This aspect of perception is well illustrated by the use of ambiguous figures that can be seen in two different ways. When people view such a stimulus they almost universally describe what they are seeing as jumping between two states. If it is agreed that this perceptual phenomenon is causally linked to the activity of nerve cells, the state jumps would have to occur in conjunction with changes in neural activity somewhere in the nervous system. Our experiments suggest that hippocampal place cells are part of a perceptual system. We conducted variations of a 'cue-card rotation' experiment on rats in which the angular position of a prominent visual stimulus on the wall of cylinder is changed in the rat's presence. The three main results are that (i) place-cell firing fields remain stationary if the cue is rotated by 180 degrees, so the relation between the cue and the field is altered; (ii) firing fields rotate by 45 degrees when the cue is rotated by 45 degrees, so the relation between the field and the card is maintained; and (iii) if the cue is first rotated by 180 degrees and then rotated in a series of 45 degrees steps, the field winds up at a different angular position relative to the card when the card is back in its original position. Thus, place cells can fire in two different ways in response to a continuously viewed stimulus. We conclude that place cells reveal that the hippocampal mapping system also has properties expected of a perceptual system.

Young People Considering Nursing as a Career: Starters vs. Non-starters

This study focused on applicants who were accepted to a nursing education program but did not begin their studies, thus wasting time, effort and money. Of 953 accepted applicants, 27% did not enter the program. Significant variables differentiating starters from non-starters were higher psychometric score, higher paternal education, lower priority for nursing studies, older age, non-Israeli country of birth and not completed army service. The study relating to starters vs. non-starters is one aspect of a large study (Ehrenfeld, Rotenberg, Sharon, & Bergman, 1995). In most nursing education programs the number of applicants exceed the faculty's capacity, and suitable candidates must be rejected. It is therefore both wasteful and disappointing when accepted applicants change their mind and do not actually begin in the program. In light of the costs and complexities involved in the student screening process and the continuous efforts extended today all over the world to raise the standards of nursing education and care, the factors differentiating starters from non-starters may have important implications. The aim of the present study was to evaluate the screening process at the Tel Aviv University baccalaureate nursing program and determine which variables were predictive of starters and non-starters among accepted applicants.

Reasons for student attrition on nursing courses: a study

Student attrition (dropping out) wastes time and resources which schools of nursing can ill afford. This study from Israel sets out to identify the reasons for student attrition and finds that academic failure is only one factor. The authors suggest some ways in which high risk students can be identified and helped.

Mice expressing activated CaMKII lack low frequency LTP and do not form stable place cells in the CA1 region of the hippocampus

To relate different forms of synaptic plasticity to the formation and maintenance of place cells in the hippocampus, we have recorded place cells in freely behaving, transgenic mice that express a mutated Ca2+-independent form of CaM Kinase II. These mice have normal long-term potentiation (LTP) at 100 Hz, but they lack LTP in response to stimulation at 5-10 Hz and are impaired on spatial memory tasks. In these transgenic mice, the place cells in the CA1 region have three important differences from those of wild types: they are less common, less precise, and less stable. These findings suggest that LTP in the 5-10 Hz range may be important for the maintenance of place-field stability and that this stability may be essential for the storage of spatial memory.

[Are lymphocytic and collagenous colitis two forms of a single disease? Arguments taken from a biopsy quantitative study]

Collagenous colitis and lymphocytic colitis are defined by a clinicopathologic syndrome with chronic watery diarrhea, microscopic lesions of colonic biopsies, and normal barium enema and colonoscopy. A histopathological study was performed on multiple colorectal biopsies to compare 12 cases of collagenous colitis (defined by a subepithelial collagen thicker than 10 microns) and 7 cases of lymphocytic colitis (defined by a number of intraepithelial lymphocytes more than 20 per 100 epithelial cells at least in one biopsied site). The study included a semiquantitative analysis of inflammatory infiltrate in the lamina propria, crypts distortion and epithelial detachment. The number of intraepithelial lymphocytes per 100 epithelial cells was determined in surface epithelium and crypts. The subepithelial collagen thickening was studied by computerised morphometry. The intraepithelial lymphocytes, villous atrophy and thickness of the subepithelial collagen were also determined in gastric and duodenal biopsies. In collagenous colitis, the subepithelial collagenous thickness ranged from 10 to 40 microns in the colon (median 20.99 microns). In 4 cases of collagenous colitis, no thickening of the collagen plate was seen in the rectum. We found constant epithelial detachment and mucosal distortion. In lymphocytic colitis, the thickness of the subepithelial collagen ranged from 6 to 10 microns in 4 cases and was less than 6 microns in 3 cases (median 6.24 microns). The median number of intraepithelial lymphocytes in surface epithelium was 22.35 (range 18.2 to 40) in lymphocytic colitis versus 12.22 (range 4.6 to 24.4) in collagenous colitis. In conclusion, we observed an overlap of both the collagenous plate thickness and the number of intraepithelial lymphocytes in collagenous colitis and lymphocytic colitis. This result favours a unified histogenesis for these two entities.

Helicobacter pylori infection in patients with Barrett's oesophagus: a prospective immunohistochemical study

The prevalence of Helicobacter pylori infection in patients with Barrett's oesophagus was studied prospectively. A sensitive immunohistochemical staining of H pylori was performed in oesophageal and gastric biopsies of 73 patients from a surveillance group with this condition. H pylori was detected in 11 cases of Barrett's mucosa (15%) and in 26 gastric mucosa specimens (35.6%). All cases positive in Barrett's mucosa were also positive in the stomach. In Barrett's oesophagus, H pylori was never found on specialised epithelium. The percentage of Barrett's mucosa showing inflammatory changes was similar in specimens with and without H pylori, both for chronic (81% v 79%) and acute (9% v 10%) infiltrates. These results indicate that H pylori infection does not play an aetiological role in Barrett's oesophagus and that colonisation of the metaplastic mucosa by this bacteria is related with the presence of gastric type mucosa in the oesophagus and of H pylori infection in the stomach.

Multicentre prospective controlled study of Barrett's oesophagus and colorectal adenomas. Groupe d'Etude de l'Oesophage de Barrett

Previous studies have suggested that patients with Barrett's oesophagus may be at increased risk of colorectal neoplasia, though the association is disputed. In a multicentre prospective study we compared the prevalence of colorectal adenomas in patients with Barrett's oesophagus and controls. Barrett's oesophagus patients (n = 104) had histological confirmation of columnar epithelium extending more than 3 cm above the gastro-oesophageal junction. The 537 controls were patients with symptoms suggesting irritable bowel syndrome. No participant had a personal history of colonic neoplasm. Each patient underwent colonoscopy. Histologically proven adenomas were found in 26 Barrett's patients (25%) and 75 controls (14%). Three colorectal cancers were discovered in each group. The prevalence of adenomas was greater in the Barrett's oesophagus group than in the control group (p < 0.01) but the relation became non-significant after adjustment for age and sex and control for other known risk factors by a logistic regression model (odds ratio 1.4 [0.7-2.7]). The relative risk of adenoma was significantly higher in patients older than 59 than in younger patients (2.2 [1.3-3.5]) and in men than in women (3.4 [2.0-5.7]). Other factors contributing significantly to the risk of adenoma were a family history of colorectal cancer (2.3 [1.1-4.8]), rectal bleeding (2.1 [1.1-3.9]), previous colonic investigation (0.3 [0.1-0.7]), and complete as opposed to partial colonoscopy (6.4 [0.8-48.3]). We conclude that Barrett's oesophagus is not an independent risk factor for colorectal neoplasia and, therefore, is not, in itself an indication for colorectal screening.

[Association of stomach ulcer and Helicobacter pylori. Prognostic implications]

Helicobacter pylori is known to be responsible for most cases of chronic gastritis, but its role in the outcome of gastric ulcer is unknown. The purpose of this study was to determine the prevalence of H. pylori infection before and after treatment of gastric ulcer, the micro-organism being untreated. The trial involved 26 patients with an acute episode of gastric ulcer, who had undergone endoscopy with biopsy of the antrum, the fundus and the ulcer rim at the initial examination and then 6 weeks and 1 year after the diagnosis. At day 0, 25 acute ulcers were associated with chronic H. pylori gastritis; one patient had neither gastritis nor H. pylori infection. The H. pylori count correlated with the activity of chronic gastritis and with the extension of intestinal metaplasia; it was not modified by the healing of gastric ulcer observed in 24/26 patients on day 360. These results confirm the existence of a close association between H. pylori, chronic gastritis and gastric ulcer. It also suggests that H. pylori is not directly involved in the healing or recurrence of gastric ulcer.

Treatment of duodenal ulcer with rioprostil: a randomized multicentre double-blind study

The effectiveness of rioprostil, 300 micrograms b.d. is evaluated in evolutive duodenal ulcer in a double-blind study in five French and North African centres. A total of 115 patients are included in the study (57 in the rioprostil group and 58 in the placebo group). After a 4-week treatment period, a significantly higher endoscopic healing rate is observed in the rioprostil group (57%) compared with the placebo group (33%) (p less than 0.01). The mean time with abdominal pain is significantly lower in the rioprostil group (5.6 +/- 4.4 days) compared to the placebo group (12.7 +/- 5 days) (p less than 0.001). Clinical and biological tolerance is excellent. The only side effect is diarrhoea (3.5% in the rioprostil group). In only one case does diarrhoea necessitate cessation of treatment. Rioprostil, 300 micrograms b.d., is thus effective in the treatment of developing duodenal ulcer.

[Treatment of duodenal ulcer outbreak with omeprazole. Results of a multicenter non-controlled study]

Sixty-one patients with symptomatic endoscopically confirmed duodenal ulcer, 5 mm or more in diameter, were treated with omeprazole 30 mg once daily in the morning for 4 weeks. Complete ulcer healing was assessed by endoscopy performed after 15 and, if necessary, 29 days of treatment. The healing rate as 83 p. 100 (49/59 patients) after 2 weeks, and 98 p. 100 (58/59 patients) after 4 weeks. Only 5 patients remained symptomatic on day 15. Fifty-six patients did not take any antacid during the course of treatment. There were few adverse effects. No clinically significant changes in laboratory parameters were observed. These results confirm: the remarkable efficiency of omeprazole in short-term treatment of duodenal ulcer, the good tolerance to this drug, at least in short duration treatment.

Attitudes and beliefs versus study results: exemplified by attrition in a school of nursing in Israel during 1968-1974

Head nurses and faculty members have their own beliefs on and attitudes towards the process of selecting candidates to schools of nursing. Many times these are based on impressions and/or everyday experiences that might have a crucial influence on perception of the issue. These impressions are not always verified when a study is conducted. This article reports on some of the issues and findings regarding attrition in one school for registered nurses in Israel during the years 1968-1974. It also describes what head nurses and faculty members thought to be valid criteria in the selection process, though findings revealed that things are not always as they are believed to be. For example, psychological tester recommendations were thought to be crucial in selecting candidates and preventing attrition, but no significant correlation was found between the recommendations and attrition. Head nurses thought that the main reason for attrition was dissatisfaction, although this was not found to be a stated reason. This belief of the head nurses should evidently be investigated. Findings support the author's belief that local studies are important and that faculty members and head nurses should communicate on the issue of student nurse selection and education.

Psychological tests in selection of students to schools of nursing in Israel

Psychological tests as one of the influential and, in some instances, crucial criteria in selecting candidates to schools of nursing, have long been used and during the last 25 years have been discussed in literature.