Short-term outcomes of infants born to mothers with SARS-CoV-2 infection.

OBJECTIVE: The rate of transmission of SARS-CoV-2 from mothers to infants in the peri- and post-natal period remains an area of ongoing investigation. This study aims to determine rates of development of clinically significant COVID-19 disease within 1 month among infants born to symptomatic and asymptomatic SARS-CoV-2 positive mothers. MATERIALS AND METHODS: This was a single-center, retrospective cohort study of all infants born to SARS-CoV-2 positive mothers who were admitted to the Well Baby Nursery (WBN) at New York University Langone Hospital-Brooklyn from 23 March-23 September 2020. Infants born to asymptomatic mothers were allowed to room-in, while infants born to mothers with symptoms of SARS-CoV-2 were isolated and discharged home to an alternate primary caregiver. A phone follow-up program contacted mothers at 2 weeks and 1 month post discharge to inquire about newborn symptoms, maternal symptoms, personal protective equipment (PPE) usage, and any presentations to care. Medical records were also reviewed for clinic and hospital visits to determine if exposed infants developed any symptoms following discharge. RESULTS: Of 1903 deliveries during the study period, 131 mothers (21 symptomatic, 110 asymptomatic) tested positive for SARS-CoV-2 and had infants admitted to the WBN. 57 infants (21 born to symptomatic mothers, 36 born to asymptomatic mothers) were tested prior to discharge, and none were positive. 121 of 133 infants had at least 1 follow up call in the study period. Of these, 31 had symptoms potentially concerning for SARS-CoV-2 infection or Multisystem Inflammatory Syndrome in Children, and 19 presented to medical care for these symptoms. 4 infants had SARS- CoV-2 testing after discharge, and none were positive. 2 infants were admitted to the hospital for fever but neither had a positive SARS-CoV-2 result. 65% of mothers reported always adhering to PPE recommendations. CONCLUSION: Our results suggest that infants born both to symptomatic and asymptomatic mothers are unlikely to develop clinically significant COVID-19 disease in the peri- and post-natal periods.

Impact of paediatric tonsillectomy perioperative management on pain, nausea and recovery: A prospective cohort study.

AIM: Tonsillectomy procedures are a core element of paediatrics; however, perioperative management differs. This study aimed to describe tonsillectomy management, including the burden of pain, nausea and delayed recovery. METHODS: A prospective cohort study was undertaken through an audit of tonsillectomy perioperative practice and recovery and survey interviews with family members 7-14 days post-surgery. The study was undertaken at an Australian tertiary referral paediatric hospital between June and September 2016. RESULTS: The audit included 255 children undergoing tonsillectomy, with 127 family members interviewed. Most participants underwent adenotonsillectomy (n = 216; 85%), with a primary diagnosis of obstructive sleep apnoea (n = 205; 80%) and a mean age of 7 years (standard deviation; 3.9). A variety of intra-operative pain relief and antiemetics was administered. Pain was present in 29% (n = 26) of participants at ward return, increasing to 32-45% at 4-20 h and decreasing to 21% (n = 15) at discharge. A third of the children (32%; n = 41) had moderate to severe pain at post-discharge interview, and 30% (n = 38) experienced nausea at home. Most parents (82%; n = 104) were still giving regular paracetamol at 7 days post-operatively, and 31% (n = 39) had finished their oxycodone. Of the participants, 14% (n = 26) presented to the emergency department within 7 days of discharge; 8% (n = 20) of the total cohort were re-admitted. CONCLUSIONS: There was variety in perioperative and post-discharge care. Pain scores were infrequently documented post-tonsillectomy, and parents are generally dissatisfied with the management of post-operative pain and nausea. Further research is needed to provide a more consistent approach to perioperative management to promote recovery.

Preschool predictors of reading ability in the first year of schooling in children with ASD.

A high percentage of children with Autism Spectrum Disorder (ASD) show elevated challenges in learning to read. We investigated longitudinal predictors of reading skills in 41 children diagnosed with ASD. All children completed measures of precursor literacy skills at the age of 4-5 years, including phonological awareness, letter sound knowledge, rapid automatic naming, name writing, and phonological memory (digit span), along with measures of word- and passage-level reading skills in their first year of formal schooling. Nonverbal cognition and letter sound knowledge accounted for 53.4% of the variance in regular single word reading at school age, with letter sound knowledge a significant individual predictor. Overall, 18 children showed reading ability scores in the average range on a standardized test of passage-level reading ability, whereas 23 children performed below expectations. These groups differed significantly on all precursor literacy measures (at ages 4-5), except autism symptoms based on parent report. Group membership was significantly predicted by preschool receptive vocabulary, name writing, and rapid automatic naming, with high sensitivity and specificity. These results are discussed in reference to the literature describing early literacy predictors for typically developing children, highlighting key areas for future intervention and support. Autism Res 2018, 11: 1332-1344. © 2018 International Society for Autism Research, Wiley Periodicals, Inc. LAY SUMMARY: Children with autism are at increased risk of persistent reading difficulties. We examined whether preschool reading-related skills linked to later reading ability. Performance on the following three tasks administered at preschool predicted children who showed early reading success versus below expectations in their first year of school: vocabulary, name writing, and rapid naming of familiar objects and shapes. These results can inform future interventions.

Prominent role of alpha3/alpha6beta2* nAChRs in regulating evoked dopamine release in primate putamen: effect of long-term nicotine treatment.

Brain dopaminergic systems are critical in motor control as evidenced by findings that their disruption results in movement disorders such as Parkinson's disease. Nicotinic acetylcholine receptor (nAChR) activation plays an important role in regulating striatal dopaminergic function. Rodent studies show that short-term nicotine exposure influences stimulated striatal dopamine release with responsiveness dependent on neuronal activity. However, studies have not yet been done in nonhuman primates, nor has work been done to evaluate the effect of long-term nicotine exposure, which is relevant for therapies for chronic neurological disorders. Here, we used voltammetry to assess the role of nAChRs on evoked dopamine release from monkey putamen slices. In both ventral and dorsal putamen, alpha3/alpha6beta2(*) nAChRs regulated > or =80% of non-burst- (single pulse) nAChR-modulated dopamine release, and alpha4beta2(*) nAChRs regulated the remainder. Similar results were observed with burst-firing in ventral but not dorsal putamen, indicating that nAChR-modulated effects on release depend on the subregion and firing frequency. Next, we investigated the consequence of long-term nicotine exposure via the drinking water on nAChR-modulated responsiveness. Nicotine treatment altered both non-burst- and burst-stimulated dopamine release in ventral but not dorsal putamen. Altogether, these data support a predominant role for alpha3/alpha6beta2(*) nAChRs in the regulation of evoked dopamine release in nonhuman primate putamen. They also show that long-term nicotine treatment selectively modifies nAChR-modulated release in distinct striatal subregions. These findings have implications for the development of treatments for addiction and neurological disorders with nAChR dysfunction.

Nicotinic acetylcholine receptor subunit mRNA expression in adult and developing rat medullary catecholamine neurons.

Nicotinic acetylcholine receptors (nAChRs) mediate numerous visceral functions via medullary catecholamine (CA) neurons found in the nucleus tractus solitarius (NTS), dorsal motor nucleus of the vagus (DMV), and ventrolateral medulla (VLM). However, the nAChR subtypes involved are not known. We have therefore characterized expression of nine nAChR subunit mRNAs in adult and developing rat medullary CA nuclei using combined isotopic/nonisotopic in situ hybridization. Tyrosine hydroxylase (TH) mRNA, the CA-synthesizing enzyme, was used as a marker for CA neurons, because these nuclei consist of heterogeneous populations of cells. Subunit mRNA expression varied within and between nuclei, along the rostrocaudal axis, between cell types, and across development. All CA neurons expressed beta2 mRNA, whereas alpha2 mRNA was completely absent. alpha6 And beta3 mRNA expression were restricted mainly to the VLM. alpha4, alpha5, And alpha7 mRNA expression was significantly greater in the rostral than in the caudal VLM. alpha3 And beta4 mRNAs were highly expressed in the dorsal region of the NTS, whereas dense alpha7 mRNA expression was restricted to the DMV and ventral NTS. The remaining subunit mRNAs were detected to some degree in both DMV and NTS. Except for alpha4 mRNA, which peaked prenatally, expression levels of subunit transcripts in the NTS and DMV were lower during development compared with adults. In the VLM, alpha3, alpha4, and alpha5 mRNAs expression peaked perinatally, whereas alpha6 and beta3 levels increased with age. These variations in nAChR subunit mRNA expression suggest that different receptor subtypes may produce function-specific regulation of medullary CA systems.

Nicotine and Parkinson's disease: implications for therapy.

Accumulating evidence suggests that nicotine, a drug that stimulates nicotinic acetylcholine receptors, may be of therapeutic value in Parkinson's disease. Beneficial effects may be several-fold. One of these is a protective action against nigrostriatal damage. This possibility stems from the results of epidemiological studies that consistently demonstrate an inverse correlation between tobacco use and Parkinson's disease. This reduced incidence of Parkinson's disease has been attributed to the nicotine in tobacco products, at least in part, based on experimental work showing a protective effect of nicotine against toxic insults. Second, several studies suggest a symptomatic effect of nicotine in Parkinson's disease, although effects are small and somewhat variable. Third, recent data in nonhuman primates show that nicotine attenuates levodopa-induced dyskinesias, a debilitating side effect that develops in the majority of patients on levodopa therapy. Collectively, these observations suggest that nicotine or CNS selective nicotinic receptor ligands hold promise for Parkinson's disease therapy to reduce disease progression, improve symptoms, and/or decrease levodopa-induced dyskinesias.

Paraquat exposure reduces nicotinic receptor-evoked dopamine release in monkey striatum.

Paraquat, an herbicide widely used in the agricultural industry, has been associated with lung, liver, and kidney toxicity in humans. In addition, it is linked to an increased risk of Parkinson's disease. For this reason, we had previously investigated the effects of paraquat in mice and showed that it influenced striatal nicotinic receptor (nAChR) expression but not nAChR-mediated dopaminergic function. Because nonhuman primates are evolutionarily closer to humans and may better model the effects of pesticide exposure in man, we examined the effects of paraquat on striatal nAChR function and expression in monkeys. Monkeys were administered saline or paraquat once weekly for 6 weeks, after which nAChR levels and receptor-evoked [(3)H]dopamine ([(3)H]DA) release were measured in the striatum. The functional studies showed that paraquat exposure attenuated dopamine (DA) release evoked by alpha3/alpha6beta2(*) (nAChR that is composed of the alpha3 or alpha6 subunits, and beta2; the asterisk indicates the possible presence of additional subunits) nAChRs, a subtype present only on striatal dopaminergic terminals, with no decline in release mediated by alpha4beta2(*) (nAChR containing alpha4 and beta2 subunits, but not alpha3 or alpha6) nAChRs, present on both DA terminals and striatal neurons. Paraquat treatment decreased alpha4beta2(*) but not alpha3/alpha6beta2(*) nAChR expression. The differential effects of paraquat on nAChR expression and receptor-evoked [(3)H]DA release emphasize the importance of evaluating changes in functional measures. The finding that paraquat treatment has a negative impact on striatal nAChR-mediated dopaminergic activity in monkeys but not mice indicates the need for determining the effects of pesticides in higher species.

Pre-synaptic dopaminergic compensation after moderate nigrostriatal damage in non-human primates.

Despite a dramatic loss of nigrostriatal dopaminergic neurons in Parkinson's disease, clinical symptoms only arise with 70-80% reduction of striatal dopamine. The mechanisms responsible for this functional compensation are currently under debate. Although initial studies showed an enhanced pre-synaptic dopaminergic function with nigrostriatal degeneration, more recent work suggests that functional compensation is not dopamine-mediated. To address this issue, we used cyclic voltammetry to directly measure endogenous dopamine release from striatal slices of control monkeys and animals with a moderate or severe MPTP-induced dopaminergic lesion. The moderately lesioned monkeys were asymptomatic, while the severely lesioned animals were parkinsonian. In monkeys with a moderate lesion, a 300% increase was obtained in endogenous striatal dopamine release. In contrast, in striatal slices from severely lesioned animals, a small % of evoked dopamine signals were similar in amplitude to control while the greater majority were undetectable. These findings suggest that pre-synaptic dopaminergic compensation develops in residual dopaminergic terminals with moderate lesioning, but that this response is lost with severe nigrostriatal damage. Such an interpretation is supported by the results of dopamine turnover studies. This enhanced pre-synaptic dopaminergic activity may be important in maintaining normal motor function during the initial stages of Parkinson's disease.

Cotinine selectively activates a subpopulation of alpha3/alpha6beta2 nicotinic receptors in monkey striatum.

The nicotine metabolite cotinine is an abundant long-lived bio-active compound that may contribute to the overall physiological effects of tobacco use. Although its mechanism of action in the central nervous system has not been extensively investigated, cotinine is known to evoke dopamine release in the nigrostriatal pathway through an interaction at nicotinic receptors (nAChRs). Because considerable evidence now demonstrates the presence of multiple nAChRs in the striatum, the present experiments were done to determine the subtypes through which cotinine exerts its effects in monkeys, a species that expresses similar densities of striatal alpha4beta2* (nAChR containing the alpha4 and beta2 subunits, but not alpha3 or alpha6) and alpha3/alpha6beta2* (nAChR composed of the alpha3 or alpha6 subunits and beta2) nAChRs. Competition binding studies showed that cotinine interacts with both alpha4beta2* and alpha3/alpha6beta2* nAChR subtypes in the caudate, with cotinine IC(50) values for inhibition of 5-[(125) I]iodo-3-[2(S)-azetinylmethoxy]pyridine-2HCl ([(125)I]A-85380) and (125)I-alpha-conotoxinMII binding in the micromolar range. This interaction at the receptor level is of functional significance because cotinine stimulated both alpha4beta2* and alpha3/alpha6beta2* nAChR [(3)H]dopamine release from caudate synaptosomes. Our results unexpectedly showed that nicotine evokes [(3)H]dopamine release from two alpha3/alpha6beta2* nAChR populations, one of which was sensitive to cotinine and the other was not. This cotinine-insensitive subtype was only present in the medial caudate and was preferentially lost with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced nigrostriatal damage. In contrast, cotinine and nicotine elicited equivalent levels of alpha4beta2* nAChR-mediated dopamine release. These data demonstrate that cotinine functionally discriminates between two alpha3/alpha6beta2* nAChRs in monkey striatum, with the cotinine-insensitive alpha3/alpha6beta2* nAChR preferentially vulnerable to nigrostriatal damage.

Nicotine reduces levodopa-induced dyskinesias in lesioned monkeys.

OBJECTIVE: Levodopa, the gold standard for Parkinson's disease treatment, is associated with debilitating abnormal involuntary movements or dyskinesias, for which few treatments are currently available. Studies have implicated numerous neurotransmitters in the development of levodopa-induced dyskinesias. However, the cholinergic system has received little attention despite an extensive overlap between dopaminergic terminals and cholinergic interneurons in the striatum and the well-known ability of nicotine to stimulate striatal dopamine release. Our objective, therefore, was to determine whether nicotine treatment reduced levodopa-induced dyskinesias. METHODS: The effect of nicotine (provided in the drinking water) was determined on dyskinesias induced by levodopa (5 mg/kg twice daily by oral gavage) in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated monkeys. RESULTS: Nicotine pretreatment reduced peak and total levodopa-induced dyskinesias in levodopa-naive monkeys over an 8-week period, with a decrease in total dyskinesias of about 50%. A crossover study was then done in which levodopa-treated monkeys originally receiving vehicle were administered nicotine, whereas the levodopa-treated animals initially receiving nicotine were placed on vehicle. Nicotine treatment to levodopa-primed monkeys led to an approximately 35% reduction in total dyskinesias that lasted for at least 8 weeks, at which time the study was ended. In contrast, a significant increase in levodopa-induced dyskinesias was observed in the group of animals that had previously received nicotine and were then switched to vehicle. Nicotine treatment did not appear to affect the antiparkinsonian action of levodopa. INTERPRETATION: These data suggest that nicotine or selective nicotinic agonists may represent a useful treatment strategy to reduce levodopa-induced dyskinesias.

Nicotinic receptors as CNS targets for Parkinson's disease.

Parkinson's disease is a debilitating neurodegenerative movement disorder characterized by damage to the nigrostriatal dopaminergic system. Current therapies are symptomatic only and may be accompanied by serious side effects. There is therefore a continual search for novel compounds for the treatment of Parkinson's disease symptoms, as well as to reduce or halt disease progression. Nicotine administration has been reported to improve motor deficits that arise with nigrostriatal damage in parkinsonian animals and in Parkinson's disease. In addition, nicotine protects against nigrostriatal damage in experimental models, findings that have led to the suggestion that the reduced incidence of Parkinson's disease in smokers may be due to the nicotine in tobacco. Altogether, these observations suggest that nicotine treatment may be beneficial in Parkinson's disease. Nicotine interacts with multiple nicotinic receptor (nAChR) subtypes in the peripheral and central nervous system, as well as in skeletal muscle. Work to identify the subtypes affected in Parkinson's disease is therefore critical for the development of targeted therapies. Results show that striatal alpha6beta2-containing nAChRs are particularly susceptible to nigrostriatal damage, with a decline in receptor levels that closely parallels losses in striatal dopamine. In contrast, alpha4beta2-containing nAChRs are decreased to a much smaller extent under the same conditions. These observations suggest that development of nAChR agonists or antagonists targeted to alpha6beta2-containing nAChRs may represent a particularly relevant target for Parkinson's disease therapeutics.