Background: Sarcopenia, a multifactorial disorder involving metabolic disturbance, suggests potential for metabolite biomarkers. Carnitine (CN), essential for skeletal muscle energy metabolism, may be a candidate biomarker. We investigated whether CN metabolites are biomarkers for sarcopenia. Methods: Associations between the CN metabolites identified from an animal model of sarcopenia and muscle cells and sarcopenia status were evaluated in men from an age-matched discovery (72 cases, 72 controls) and a validation (21 cases, 47 controls) cohort. Results: An association between CN metabolites and sarcopenia showed in mouse and cell studies. In the discovery cohort, plasma C5-CN levels were lower in sarcopenic men (P=0.005). C5-CN levels in men tended to be associated with handgrip strength (HGS) (P=0.098) and were significantly associated with skeletal muscle mass (P=0.003). Each standard deviation increase in C5-CN levels reduced the odds of low muscle mass (odd ratio, 0.61; 95% confidence interval [CI], 0.42 to 0.89). The area under the receiver operating characteristic curve (AUROC) of CN score using a regression equation of C5-CN levels, for sarcopenia was 0.635 (95% CI, 0.544 to 0.726). In the discovery cohort, addition of CN score to HGS significantly improved AUROC from 0.646 (95% CI, 0.575 to 0.717; HGS only) to 0.727 (95% CI, 0.643 to 0.810; P=0.006; HGS+CN score). The improvement was confirmed in the validation cohort (AUROC=0.563; 95% CI, 0.470 to 0.656 for HGS; and AUROC=0.712; 95% CI, 0.569 to 0.855 for HGS+CN score; P=0.027). Conclusion C5-CN, indicative of low muscle mass, is a potential circulating biomarker for sarcopenia in men. Further studies are required to confirm these results and explore sarcopenia-related metabolomic changes.

Background: Sarcopenia, a multifactorial disorder involving metabolic disturbance, suggests potential for metabolite biomarkers. Carnitine (CN), essential for skeletal muscle energy metabolism, may be a candidate biomarker. We investigated whether CN metabolites are biomarkers for sarcopenia. Methods: Associations between the CN metabolites identified from an animal model of sarcopenia and muscle cells and sarcopenia status were evaluated in men from an age-matched discovery (72 cases, 72 controls) and a validation (21 cases, 47 controls) cohort. Results: An association between CN metabolites and sarcopenia showed in mouse and cell studies. In the discovery cohort, plasma C5-CN levels were lower in sarcopenic men (P=0.005). C5-CN levels in men tended to be associated with handgrip strength (HGS) (P=0.098) and were significantly associated with skeletal muscle mass (P=0.003). Each standard deviation increase in C5-CN levels reduced the odds of low muscle mass (odd ratio, 0.61; 95% confidence interval [CI], 0.42 to 0.89). The area under the receiver operating characteristic curve (AUROC) of CN score using a regression equation of C5-CN levels, for sarcopenia was 0.635 (95% CI, 0.544 to 0.726). In the discovery cohort, addition of CN score to HGS significantly improved AUROC from 0.646 (95% CI, 0.575 to 0.717; HGS only) to 0.727 (95% CI, 0.643 to 0.810; P=0.006; HGS+CN score). The improvement was confirmed in the validation cohort (AUROC=0.563; 95% CI, 0.470 to 0.656 for HGS; and AUROC=0.712; 95% CI, 0.569 to 0.855 for HGS+CN score; P=0.027). Conclusion C5-CN, indicative of low muscle mass, is a potential circulating biomarker for sarcopenia in men. Further studies are required to confirm these results and explore sarcopenia-related metabolomic changes.

Background: The nipple is a potential source of pathogens because its lactiferous ducts act as direct conduits from the nipple–areolar complex to the breast parenchyma. Our previous studies identified breast microbiota as a factor in postoperative complications following immediate breast reconstruction using silicone implants and acellular dermal matrix. This study aimed to investigate the correlation between preoperative nipple swab microbiota and the incidence of surgical site infections (SSIs) after autologous breast reconstruction. Methods: We conducted a retrospective chart review of patients who underwent autologous breast reconstruction following total mastectomy. Preoperative nipple swab cultures were obtained. Patient demographics, surgical characteristics, and complication rates were compared between culture-positive and culture-negative groups. Microbiological data, including antibiotic‑resistance profiles, were collected. Results: Among 39 reconstructed breasts, 18 (46.9%) had positive preoperative nipple cultures. The mean duration of drain placement was significantly longer in the culture‑positive group (14.39±3.96 days) than in the culture‑negative group (12.14±2.76 days, P=0.045). Methicillin‑susceptible Staphylococcus epidermidis accounted for 55.0% of isolates. Of the four SSIs observed, three occurred in patients with positive preoperative cultures. Conclusions Although pathogen strains differed between preoperative and postoperative settings, obtaining preoperative nipple microflora cultures and determining antibiotic‑resistance profiles can guide immediate antibiotic selection for SSIs and enhance postoperative management.

Background: Sarcopenia, a multifactorial disorder involving metabolic disturbance, suggests potential for metabolite biomarkers. Carnitine (CN), essential for skeletal muscle energy metabolism, may be a candidate biomarker. We investigated whether CN metabolites are biomarkers for sarcopenia. Methods: Associations between the CN metabolites identified from an animal model of sarcopenia and muscle cells and sarcopenia status were evaluated in men from an age-matched discovery (72 cases, 72 controls) and a validation (21 cases, 47 controls) cohort. Results: An association between CN metabolites and sarcopenia showed in mouse and cell studies. In the discovery cohort, plasma C5-CN levels were lower in sarcopenic men (P=0.005). C5-CN levels in men tended to be associated with handgrip strength (HGS) (P=0.098) and were significantly associated with skeletal muscle mass (P=0.003). Each standard deviation increase in C5-CN levels reduced the odds of low muscle mass (odd ratio, 0.61; 95% confidence interval [CI], 0.42 to 0.89). The area under the receiver operating characteristic curve (AUROC) of CN score using a regression equation of C5-CN levels, for sarcopenia was 0.635 (95% CI, 0.544 to 0.726). In the discovery cohort, addition of CN score to HGS significantly improved AUROC from 0.646 (95% CI, 0.575 to 0.717; HGS only) to 0.727 (95% CI, 0.643 to 0.810; P=0.006; HGS+CN score). The improvement was confirmed in the validation cohort (AUROC=0.563; 95% CI, 0.470 to 0.656 for HGS; and AUROC=0.712; 95% CI, 0.569 to 0.855 for HGS+CN score; P=0.027). Conclusion C5-CN, indicative of low muscle mass, is a potential circulating biomarker for sarcopenia in men. Further studies are required to confirm these results and explore sarcopenia-related metabolomic changes.

Background: The nipple is a potential source of pathogens because its lactiferous ducts act as direct conduits from the nipple–areolar complex to the breast parenchyma. Our previous studies identified breast microbiota as a factor in postoperative complications following immediate breast reconstruction using silicone implants and acellular dermal matrix. This study aimed to investigate the correlation between preoperative nipple swab microbiota and the incidence of surgical site infections (SSIs) after autologous breast reconstruction. Methods: We conducted a retrospective chart review of patients who underwent autologous breast reconstruction following total mastectomy. Preoperative nipple swab cultures were obtained. Patient demographics, surgical characteristics, and complication rates were compared between culture-positive and culture-negative groups. Microbiological data, including antibiotic‑resistance profiles, were collected. Results: Among 39 reconstructed breasts, 18 (46.9%) had positive preoperative nipple cultures. The mean duration of drain placement was significantly longer in the culture‑positive group (14.39±3.96 days) than in the culture‑negative group (12.14±2.76 days, P=0.045). Methicillin‑susceptible Staphylococcus epidermidis accounted for 55.0% of isolates. Of the four SSIs observed, three occurred in patients with positive preoperative cultures. Conclusions Although pathogen strains differed between preoperative and postoperative settings, obtaining preoperative nipple microflora cultures and determining antibiotic‑resistance profiles can guide immediate antibiotic selection for SSIs and enhance postoperative management.

Background: The nipple is a potential source of pathogens because its lactiferous ducts act as direct conduits from the nipple–areolar complex to the breast parenchyma. Our previous studies identified breast microbiota as a factor in postoperative complications following immediate breast reconstruction using silicone implants and acellular dermal matrix. This study aimed to investigate the correlation between preoperative nipple swab microbiota and the incidence of surgical site infections (SSIs) after autologous breast reconstruction. Methods: We conducted a retrospective chart review of patients who underwent autologous breast reconstruction following total mastectomy. Preoperative nipple swab cultures were obtained. Patient demographics, surgical characteristics, and complication rates were compared between culture-positive and culture-negative groups. Microbiological data, including antibiotic‑resistance profiles, were collected. Results: Among 39 reconstructed breasts, 18 (46.9%) had positive preoperative nipple cultures. The mean duration of drain placement was significantly longer in the culture‑positive group (14.39±3.96 days) than in the culture‑negative group (12.14±2.76 days, P=0.045). Methicillin‑susceptible Staphylococcus epidermidis accounted for 55.0% of isolates. Of the four SSIs observed, three occurred in patients with positive preoperative cultures. Conclusions Although pathogen strains differed between preoperative and postoperative settings, obtaining preoperative nipple microflora cultures and determining antibiotic‑resistance profiles can guide immediate antibiotic selection for SSIs and enhance postoperative management.

Background: Sarcopenia, a multifactorial disorder involving metabolic disturbance, suggests potential for metabolite biomarkers. Carnitine (CN), essential for skeletal muscle energy metabolism, may be a candidate biomarker. We investigated whether CN metabolites are biomarkers for sarcopenia. Methods: Associations between the CN metabolites identified from an animal model of sarcopenia and muscle cells and sarcopenia status were evaluated in men from an age-matched discovery (72 cases, 72 controls) and a validation (21 cases, 47 controls) cohort. Results: An association between CN metabolites and sarcopenia showed in mouse and cell studies. In the discovery cohort, plasma C5-CN levels were lower in sarcopenic men (P=0.005). C5-CN levels in men tended to be associated with handgrip strength (HGS) (P=0.098) and were significantly associated with skeletal muscle mass (P=0.003). Each standard deviation increase in C5-CN levels reduced the odds of low muscle mass (odd ratio, 0.61; 95% confidence interval [CI], 0.42 to 0.89). The area under the receiver operating characteristic curve (AUROC) of CN score using a regression equation of C5-CN levels, for sarcopenia was 0.635 (95% CI, 0.544 to 0.726). In the discovery cohort, addition of CN score to HGS significantly improved AUROC from 0.646 (95% CI, 0.575 to 0.717; HGS only) to 0.727 (95% CI, 0.643 to 0.810; P=0.006; HGS+CN score). The improvement was confirmed in the validation cohort (AUROC=0.563; 95% CI, 0.470 to 0.656 for HGS; and AUROC=0.712; 95% CI, 0.569 to 0.855 for HGS+CN score; P=0.027). Conclusion C5-CN, indicative of low muscle mass, is a potential circulating biomarker for sarcopenia in men. Further studies are required to confirm these results and explore sarcopenia-related metabolomic changes.