1. Body weight changes in mice after fecal material transplantation. (Time Frame - Between days 0 and 30): Body weight (g)
Secondary outcome:
1. Differences in fecal microbiota (Time Frame - at diagnosis): by 16S rRNA gene amplicon sequencing and functional profiles by metagenomic sequencing between cachectic patients non-cachectic patients and healthy volunteers
2. Body weight (Time Frame - at diagnosis): in kilograms between cachectic patients non-cachectic patients and healthy volunteers
3. Waist-to-hip ratio (Time Frame - at diagnosis): waist circumference (cm) and hip circumference (cm) between cachectic patients non-cachectic patients and healthy volunteers
4. Fat mass (Time Frame - at diagnosis): by bioelectrical impedance analysis (BIA) between cachectic patients non-cachectic patients and healthy volunteers
5. Fat-free mass (Time Frame - at diagnosis): by bioelectrical impedance analysis (BIA) between cachectic patients non-cachectic patients and healthy volunteers
6. Muscle mass (Time Frame - at diagnosis): surfaces of the paraspinal and abdominal wall muscles at the level of L3-L4 disk space by CT for pancreatic cancer patients
7. Nutritional intake (Time Frame - at diagnosis): by 3-day food diary between cachectic patients non-cachectic patients and healthy volunteers
8. Resting energy expenditure (REE) (Time Frame - at diagnosis): by indirect calorimetry between cachectic patients non-cachectic patients and healthy volunteers
9. Appetite (Time Frame - at diagnosis): by visual analogue scale ranging from 0 to 100 mm between cachectic patients non-cachectic patients and healthy volunteers
10. Appetite (Time Frame - at diagnosis): by fasting level of plasma ghrelin between cachectic patients non-cachectic patients and healthy volunteers
11. Appetite (Time Frame - at diagnosis): by fasting level of plasma leptin between cachectic patients non-cachectic patients and healthy volunteers
12. Appetite (Time Frame - at diagnosis): by fasting level of plasma glucagon-like peptide-1 (GLP-1) between cachectic patients non-cachectic patients and healthy volunteers
13. Appetite (Time Frame - at diagnosis): by fasting level of plasma neuropeptide Y between cachectic patients non-cachectic patients and healthy volunteers
14. Appetite (Time Frame - at diagnosis): by fasting level of plasma cholecystokinin between cachectic patients non-cachectic patients and healthy volunteers
15. Homeostatic model assessment (HOMA)-score (Time Frame - at diagnosis): by fasting glycemia (mmol/l) and fasting insulinemia (mU/ml)) between cachectic patients non-cachectic patients and healthy volunteers
16. Glycemia (Time Frame - at diagnosis): by fasting glycemia (mmol/l) between cachectic patients non-cachectic patients and healthy volunteers
17. Insulinemia (Time Frame - at diagnosis): by fasting insulinemia (mU/ml) between cachectic patients non-cachectic patients and healthy volunteers
18. Physical function (Time Frame - at diagnosis): by handgrip strength between cachectic patients non-cachectic patients and healthy volunteers
19. Physical activity (Time Frame - at diagnosis): by the International Physical Activity Questionnaire (IPAQ) between cachectic patients non-cachectic patients and healthy volunteers
20. Quality of life (Time Frame - at diagnosis): by the European Organisation for Research and Treatment of Cancer questionnaire (EORTC QLQ-C30) between cachectic patients non-cachectic patients and healthy volunteers
21. Mortality (Time Frame - at diagnosis): by tumor progression between cachectic patients non-cachectic patients
22. Oral microbiota (Time Frame - at diagnosis): by 16SrRNA gene amplicon sequencing and metagenomic sequencing between cachectic patients non-cachectic patients and healthy volunteers
23. Epithelial permeability (Time Frame - at diagnosis): by fasting levels of plasma zonulin between cachectic patients non-cachectic patients and healthy volunteers
24. Epithelial permeability (Time Frame - at diagnosis): by fasting levels of plasma lipopolysaccharide-binding protein between cachectic patients non-cachectic patients and healthy volunteers
25. Epithelial permeability (Time Frame - at diagnosis): by fasting levels of plasma glucagon-like peptide-2 between cachectic patients non-cachectic patients and healthy volunteers
26. GALT function and systemic inflammation (Time Frame - at diagnosis): by fasting plasma level of C-reactive protein (CRP) and cytokines between cachectic patients non-cachectic patients and healthy volunteers
27. GALT function and systemic inflammation (Time Frame - at diagnosis): by peripheral blood T regulatory cells (Tregs) levels and phenotype between cachectic patients non-cachectic patients and healthy volunteers
28. GALT function and systemic inflammation (Time Frame - at diagnosis): by myeloid derived suppressor cells (MDSC) levels and phenotype between cachectic patients non-cachectic patients and healthy volunteers