Development of anatomically and lesion contrast-guided partial volume correction: new 3D formalisms and validation in phantom and clinical studies

Annals of Nuclear Medicine - The aim of the study was to correct for partial volume effect in positron emission imaging studies which is the most influential factors using three-dimensional (3D)...     

The Pregnancy,Arsenic, and Immune Response (PAIR) Study in rural northern Bangladesh

Background

Arsenic exposure and micronutrient deficiencies may alter immune reactivity to influenza vaccination in pregnant women, transplacental transfer of maternal antibodies to the foetus, and maternal and infant acute morbidity.

Objectives

The Pregnancy, Arsenic, and Immune Response (PAIR) Study was designed to assess whether arsenic exposure and micronutrient deficiencies alter maternal and newborn immunity and acute morbidity following maternal seasonal influenza vaccination during pregnancy.

Population

The PAIR Study recruited pregnant women across a large rural study area in Gaibandha District, northern Bangladesh, 2018–2019.

Design

Prospective, longitudinal pregnancy and birth cohort.

Methods

We conducted home visits to enrol pregnant women in the late first or early second trimester (11–17 weeks of gestational age). Women received a quadrivalent seasonal inactivated influenza vaccine at enrolment. Follow-up included up to 13 visits between enrolment and 3 months postpartum. Arsenic was measured in drinking water and maternal urine. Micronutrient deficiencies were assessed using plasma biomarkers. Vaccine-specific antibody titres were measured in maternal and infant serum. Weekly telephone surveillance ascertained acute morbidity symptoms in women and infants.

Preliminary Results

We enrolled 784 pregnant women between October 2018 and March 2019. Of 784 women who enrolled, 736 (93.9%) delivered live births and 551 (70.3%) completed follow-up visits to 3 months postpartum. Arsenic was detected (≥0.02 μg/L) in 99.7% of water specimens collected from participants at enrolment. The medians (interquartile ranges) of water and urinary arsenic at enrolment were 5.1 (0.5, 25.1) μg/L and 33.1 (19.6, 56.5) μg/L, respectively. Water and urinary arsenic were strongly correlated (Spearman's ⍴ = 0.72) among women with water arsenic ≥ median but weakly correlated (⍴ = 0.17) among women with water arsenic < median.

Conclusions

The PAIR Study is well positioned to examine the effects of low-moderate arsenic exposure and micronutrient deficiencies on immune outcomes in women and infants. Registration : NCT03930017.     

Proposal for the existence of a nasogastric reflex in humans, as a potential cause of upper gastrointestinal symptoms

The nose is a gateway of air from the environment to the body and with its rich innervation from the olfactory and trigeminal nerves plays a critical role as a sensor in both human beings and primitive animals. Irritation of the nasal or paranasal mucosa may initiate a severe bradycardia, apnea, and vasoconstriction and increase the pulmonary airflow resistance. However, the interaction between nasal mucosa and the upper gastrointestinal tract is more often than not neglected in the clinical literature. We propose that a nasogastric reflex might exist with its afferent and efferent loops being the trigeminal and vagus nerves, respectively. The central connection of these loops is located at the pontomedullary level. The sensory inputs from the nasal mucosa to the general somatic afferent component of the brainstem including the pontine and medullary trigeminal nucleuses may induce the neighboring nucleus of the solitary tract and dorsal motor nucleus of the vagus. This initiates, via the efferent fibers of the vagus nerve, the manifestations of the vagal stimulation. The presence of a nasogastric reflex may warrant considerations as diseases of nose and paranasal sinuses may be the cause upper gastrointestinal symptmatology.