Edta buffered collection tubes

The study was approved by the Ethics Committee of Ulm University and was conducted in accordance with the Declaration of Helsinki. Written informed consent was obtained from all subjects prior to their participation. Women were recruited at the maternity ward of Ulm University Hospital within 1 week after parturition and were invited to participate at two consecutive time points (t₀, t₁). Time point t₀ was up to 6 days after delivery in the maternity ward of the Ulm University Hospital and consisted of the assessment of basic sociodemographic, medical and childhood-related data (CTQ) (Bader et al., 2009 (link)). At t₁, 3 months postpartum, mothers were invited for a psycho-diagnostic interview at the Clinical & Biological Psychology work group (Ulm University). After a resting phase of ~15–20 min, the attachment representation was assessed with the Adult Attachment Projective Picture System (AAP) (George and West, 2012 ). Both time points (t₀ and t₁) were supervised by trained psychologists. Before the psychological assessment, whole blood samples were collected by venous puncture into EDTA-buffered collection tubes (Sarstedt, Nuermbrecht, Germany) for the Ficoll-based isolation of PBMC. OXT levels were measured in plasma aliquots generated from another EDTA-buffered sample of whole blood immediately before the Adult Attachment Projective Picture System (AAP).

EDTA-buffered collection tubes (Sarstedt, Nümbrecht, Germany) were used for the collection of whole blood samples by venous puncture between 7 a.m. and 2 p.m. Data on the precise time of blood collection was available from a subcohort of N = 32 study participants (N = 14 MDD patients and N = 18 control subjects). In this subcohort, there was no significant group difference in the time of blood collection between the depressed and the control group (Table 1). Subsequent to blood drawings, peripheral blood mononuclear cells (PBMC) were isolated from whole blood by Ficoll-Hypaque gradient centrifugation according to the manufacturer’s protocol (GE Healthcare, Chalfon St Giles, UK) and isolated cells were stored frozen at −80 °C in cryoprotective freezing medium (dimethyl sulphoxide: Sigma-Aldrich, St. Louis, MO, USA; fetal calf serum: Sigma-Aldrich; dilution 1:10).

The study was approved by the ethics committee of the medical faculty Giessen, Germany (No. 159/17) and performed in accordance with the Helsinki Declaration. Written informed consent was given by each patient or patient’s legal representative. Male and female patients aged 48–83 years (median age = 67) undergoing major surgery of the pancreas (n = 8; female = 4, male = 4) or esophagectomy (n = 4; all male) were recruited at the University Hospital of Giessen, Germany. All patients underwent elective surgery for oncological tumor resection of the esophagus (n = 8) or the pancreas (n = 4). Patients with preexisting increased inflammatory parameters and septic patients were excluded from the study. The medication prescribed prior to the surgery was checked for potential interactions with IL-1β, as far as known from the literature. All patients underwent anesthesia according to a standardized regimen. The first venous blood sample was collected shortly before the operation as well as 0 to 2 h, 24 to 48 h, 72 to 96 h, and 7 to 9 days after the operation. Venous blood was collected into EDTA-buffered collection tubes (Sarstedt, Nürnberg, Germany) and subsequently subjected to a Ficoll-Hypaque (Sigma-Aldrich, Darmstadt, Germany) gradient. After centrifugation, the upper blood plasma layer was harvested and stored at −20 °C.