Mesocricetus auratus

Local interviewers conducted the screening interviews, and the validation interviews were conducted by expert interviewers. Between December 2016 and January 2017, we recruited six local interviewers (three men and three women). The local interviewers were fluent in Kurdish and Arabic and they had at least a Bachelor’s degree in psychology or social work. Each interviewer attended a one-week intensive theoretical and practical training course on the study instruments. Due to the absence of reliable census data from the refugee camps, we used a pragmatic sampling approach based on a random selection of individuals and households. The camp was sub-divided according to approximately equal household and population size. Local interviewers were assigned to the resulting zones and instructed to randomly select a sampling direction by spinning a pen from the zone center. The first household with one distance to another was selected and from each household, only main householder couples were interviewed.
Our study is part of a much more extensive and cross-national project, which aims to study psychosocial consequences of migration among Iraqi IDPs and Syrian refugees. In the current study, we interviewed displaced Iraqi and Syrian people. We began with a background questionnaire, followed by a war-related events checklist and Life Events Checklist for DSM-5 (LEC-5) [18 ]. Psychopathology was assessed using the PCL-5 and the depression section of the Hopkins symptom checklist [19 (link)]. Participants were fully informed about the procedures of the current study through a standardized informed consent, which included information about aims of our study, confidentiality, potential risks and discomforts, the right to withdraw without prejudice, benefits, and data protection. Verbal informed consent was given, and interviewers documented informed consent for each participant. The interviewers were matched in gender to the interviewees and they were asked about their readiness for re-interview by different interviewers. All participants (except three couples, who had moved to a new location) assented to a further interview. Two weeks later forty-nine couples between 18 and 67 years of age (48% Iraqi and 52% Syrian) were chosen randomly for re-interview by four expert clinical psychologists (two women and two men).
The expert interviewers had at least a Master’s degree in clinical psychology and more than four years clinical experience with highly vulnerable populations including survivors of war, displacement, torture, genocide, and family and gender-based violence. All clinical psychologists were university lecturers at the department of clinical psychology at Koya University in the KRI, and they partially worked as psychotherapists at Koya university’s outpatient clinic. This clinic offers psychological diagnostics as well as counseling and psychotherapy for individuals with different mental health problems in including trauma and PTSD.
About 15 days after the first interview, the expert interviewers conducted validation interviews based on the same instruments. However, the experts were instructed to ask the questions of the PCL in the form of a structured clinical interview. For every single PTSD symptom listed in the PCL5, the clinical experts asked about symptom’s presence and it’s occurrences over the past month. They were instructed to explore as much information as needed about the intensity, relevance, and frequency of each symptom to be able to judge the clinical significance of each symptom. We perceived that this procedure was the best approximation to culturally sensitive structured interviews that have been recognized as a standard gold for diagnosing PTSD.
Clinically significant symptoms were rated at least as “2 = Moderate”. Expert diagnosis of PTSD was then determined using the DSM-5 algorithm, counting all symptoms rated ‘two or more’ as a present. The clinical psychologists were fluent in Kurdish and Arabic languages, and they were blind to the results of the screening interviews. The ethical review committees of Bielefeld University in Germany and Koya University in the KRI approved all study procedures.

Experimenters scanned all the tissue slices with a fluorescent microscope to identify brain regions that expressed either MC3R or MC4R mRNA. Twenty-six brain regions were chosen based on findings in previous literature, functional sites of melanocortin action, and visual inspection of expression within tissue by the experimenter. The 26 brain regions were identified based on A Stereotaxic Atlas of the Golden Hamster Brain (Morin and Wood, 2001 ). Schematic diagrams from the hamster atlas were used at the level that corresponds to where the region of interest was imaged and overlayed with a color fill-in using BioRender to help illustrate the mRNA labeling within a region. The serial sections were taken at a specific location (matched across brains) within each brain region, as indicated by the atlas plates and represent a rostral-caudal distance of less than 0.5 mm. Anatomical abbreviations are as follows:

ARC	Arcuate nucleus of the hypothalamus
BIC	Nucleus of the brachium of the inferior colliculus
BNST	Bed nucleus of the stria terminalis
CPu medial, lateral, dorsal	Caudate-putamen medial, lateral, dorsal
DEn	Dorsal endopiriform nucleus
DRN	Dorsal raphe nucleus
HPC	Hippocampus (dorsal/ventral CA1, CA2)
IL	Infralimbic cortex
LHb	Lateral habenula
LS	Lateral septum
MePD	Medial amygdaloid nucleus, Posterodorsal part
MD	Mediodorsal thalamic nucleus
MS	Medial septum
MPOA	Medial preoptic area
NAc core	Nucleus accumbens core
NAc shell	Nucleus accumbens shell
OT	Olfactory tubercle
PAG	Periaqueductal gray
PrL	Prelimbic cortex
PVN	Periventricular hypothalamus
VMH	Ventromedial hypothalamus
VTA	Ventral tegmental area

All images were acquired on a Leica TCS SPE confocal microscope under the same scanning parameters. An image was collected in the left and right hemisphere from two tissue sections (in series) for all brain regions for each subject (resulting in a sample of four images for each brain region for each subject). Images were collected with a 20X/0.60 advanced correction system objective with a pixel distribution of 1,024 × 1,024 at a frequency of 8 kHz. A solid-state laser with 488 and 532 nm wavelengths and an ultra-high dynamic PMT detector was utilized to capture z-stack images with 1.5 μm spacing for a maximum of 15 steps. The pinhole size was 1 airy unit (AU), 2 frames were averaged, and optical zoom was 1.00X. 3D images produced were 550 × 550 × 14 μm.

Male Golden Syrian hamsters (n=6) aged 6-8 weeks, were vaccinated according to the groupings in Figure 1B with a dose of 1x10⁹ infectious units (IU) diluted in 1xPBS in a total volume of 100 µL for intranasal vaccination (50 µL/nostril) and 1 mL total volume for oral gavage. Vaccinations occurred four weeks apart. Serum, nasal washes, and oral swabs were collected on day -1 (D1), day 27 (D27), and day 41 (D41) as described below. At D52, the animals were anesthetized by injecting 80 mg/kg ketamine and 5 mg/kg xylazine via intramuscular route in preparation for challenge. Animals were challenged with an appropriate dose via intranasal administration using a total volume of 100 μL per animal (50 μL/nostril), administered dropwise. SARS-CoV-2 delta variant (ATCC NR-56116 LOT#: 70047614) was dosed at 3.48x10³ TCID₅₀ per hamster and SARS-CoV-2 omicron variant (ATCC NR-56486 LOT#: 70049695 was dosed at 4.8x10⁴ TCID₅₀ per hamster as pre-determined in titration studies performed by Bioqual, Inc. Animals were monitored daily for any abnormal clinical observation and body weights were recorded. All in-life animal handling occurred at Bioqual, Inc (Rockville, MD).