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We aimed to investigate the changes in vitamin D levels and factors associated with vitamin D deficiency (VDD) during the first year of life in Korean preterm infants. We enrolled 333 preterm infants who were born at Kyungpook National University Children’s Hospital between March 2013 and December 2019. 25-hydroxyvitamin D (25-OHD) levels and medical records were collected at birth, 6 months, and 12 months of age. The mean gestational age was 33.4 ± 2.3 weeks and mean 25-OHD levels at birth were 18.2 ± 13.5 ng/mL. The incidence of VDD was 82.8%, 30.6%, and 27.0% at birth, 6 months, and 12 months, respectively. The incidence of severe VDD (25-OHD < 10 ng/mL) was 31.5%, 1.5%, and 0%, at birth, 6 months, and 12 months, respectively. Among infants with severe VDD, the deficiency persisted in 49.6% at 6 months, and 35.3% at 12 months. The strongest predictor of VDD during follow-up was 25-OHD concentration at birth. Vitamin D supplementation at 400 IU/day did not affect vitamin D levels during the first year of life. Therefore, it is important to prevent neonatal VDD through maternal vitamin D supplementation during pregnancy. Further research is needed to determine the optimal vitamin D supplementation dose for Korean preterm infants.  相似文献   
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BackgroundAn isolated tibial component revision could be a treatment option for isolated tibial side loosening; however, few studies have proved its efficacy. This study aimed to compare the clinical and radiological outcomes between isolated (tibial component) and total (femoral and tibial component) revision total knee arthroplasty (TKA).MethodsBetween January 2008 and February 2017, 31 patients underwent revision TKA for isolated tibial side loosening; 14 underwent an isolated tibial component revision (isolated group) and 17 underwent total (both femoral and tibial components) revision surgery (total group). The postoperative range of motion (ROM), Western Ontario and McMaster Universities osteoarthritis (WOMAC) index, Knee Society knee score (KSKS), Knee Society function score (KSFS), and mechanical axis (MA) were compared between the two groups. The intraoperative tourniquet time and amount of blood drainage were also compared.ResultsThe mean follow-up durations in the isolated and total groups were 40.7 and 56.1 months, respectively. Both groups had similar postoperative ROM, WOMAC index, KSKS, KSFS, and MA; however, significantly shorter tourniquet time (105.2 vs. 154.6 min, P < 0.001) and less blood drainage (417.2 vs. 968.1 ml, P < 0.001) were noted in the isolated group than in the total group.ConclusionIsolated tibial component revision TKA for tibial component loosening showed comparable clinical and radiological outcomes to those of total revision TKA. The advantages of the isolated tibial component revision surgery were short operation time and small blood loss.Study designLevel III, Retrospective comparative study.  相似文献   
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BackgroundSecondary biliary cirrhosis (SBC) represents a unique form of cirrhosis that develops in the liver secondary to persistent biliary obstruction. This study aimed to review the living donor liver transplants (LDLTs) performed at our center for patients with SBC and end-stage liver disease and to share the perioperative strategies undertaken to achieve satisfactory outcomes.MethodsThe medical records of 29 patients who underwent LDLT for SBC between December 1994 and July 2018 at the Asan Medical Center (Seoul, South Korea) were retrospectively reviewed. Their clinical data were extracted and statistically analyzed. Survival curves were computed.ResultsThe perioperative and in-hospital morbidity rates were 72.4% and 10.3%, respectively. The overall mean recipient follow-up was 80.0 (SD, 66.4) months (range, 0.8-246.8 months). Patient survival rates after 1, 3, 5, and 10 years after transplant were 82.8%, 79.3%, 79.3%, and 79.3%, respectively. For liver grafts, the survival rates were 82.8%, 75.8%, 75.8%, and 75.8% at 1, 3, 5, and 10 years, respectively.ConclusionsLDLT is potentially a final lifesaving resort for patients with SBC with portal hypertension. However, considering the difficulty of surgery and perioperative management, LDLT should be performed by experienced transplant surgeons in a center where a multidisciplinary approach is possible.  相似文献   
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Bone metastasis is a complication of prostate cancer in up to 90% of men afflicted with advanced disease. Therapies that reduce androgen exposure remain at the forefront of treatment. However, most prostate cancers transition to a state whereby reducing testicular androgen action becomes ineffective. A common mechanism of this transition is intratumoral production of testosterone (T) using the adrenal androgen precursor dehydroepiandrosterone (DHEA) through enzymatic conversion by 3β- and 17β-hydroxysteroid dehydrogenases (3βHSD and 17βHSD). Given the ability of prostate cancer to form blastic metastases in bone, we hypothesized that osteoblasts might be a source of androgen synthesis. RNA expression analyses of murine osteoblasts and human bone confirmed that at least one 3βHSD and 17βHSD enzyme isoform was expressed, suggesting that osteoblasts are capable of generating androgens from adrenal DHEA. Murine osteoblasts were treated with 100 nM and 1 μM DHEA or vehicle control. Conditioned media from these osteoblasts were assayed for intermediate and active androgens by liquid chromatography–tandem mass spectrometry. As DHEA was consumed, the androgen intermediates androstenediol and androstenedione were generated and subsequently converted to T. Conditioned media of DHEA-treated osteoblasts increased androgen receptor (AR) signaling, prostate-specific antigen (PSA) production, and cell numbers of the androgen-sensitive prostate cancer cell lines C4-2B and LNCaP. DHEA did not induce AR signaling in osteoblasts despite AR expression in this cell type. We describe an unreported function of osteoblasts as a source of T that is especially relevant during androgen-responsive metastatic prostate cancer invasion into bone. © 2021 American Society for Bone and Mineral Research (ASBMR). This article has been contributed to by US Government employees and their work is in the public domain in the USA.  相似文献   
108.
BackgroundThere is an increasing demand for prognostic immune biomarkers of cancer. The prognostic significance of immune markers has been shown for various cancers, but biomarkers of bladder cancer (BCa) have not been fully evaluated. To clarify the role of human leukocyte antigen DR alpha chain (HLA-DRA) in BCa development, we examined expression of HLA-DRA mRNA in tissue samples of non-muscle invasive bladder cancer (NMIBC) and muscle invasive bladder cancer (MIBC).Materials and MethodsTissues of 96 NMIBC, 43 MIBC and 59 controls comprising noncancerous BCa surrounding tissues were used to examine the expression of HLA-DRA gene by real-time polymerase chain reaction. The expression of up-stream genes regulating HLA-DRA were also measured to explain the role of HLA-DRA in BCa.ResultsPatients with high grade NMIBC showed higher expression of HLA-DRA than those with low grade NMIBC (P < 0.05). In addition, NMIBC patients who progressed to MIBC showed high expression of HLA-DRA mRNA. Kaplan-Meier analysis showed that NMIBC patients with low expression of HLA-DRA had better progression-free survival than those with high expression (P = 0.004). Moreover, the expression of genes regulating HLA-DRA varied in NMIBC and MIBC, indicating a different immunoregulation effect of HLA-DRA in both cancers.ConclusionsHigh expression of HLA-DRA in NMIBC patients has implications for patient stratification strategies, as well as for BCa tumor immunology.  相似文献   
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IntroductionContralateral prophylactic mastectomy has the potential to decrease the occurrence of cancer and reduce psychological burden. However, it is known that complications after bilateral mastectomy are higher compared with unilateral mastectomy. Our goal was to evaluate outcomes of immediate breast reconstruction in patients undergoing bilateral mastectomy and to compare complication rates between therapeutic and prophylactic sides.Patients and MethodsElectronic medical records of patients with unilateral breast cancer who underwent bilateral mastectomy and immediate reconstruction with expanders were reviewed. Postoperative complications were compared between therapeutic and prophylactic mastectomy sides.ResultsSixty-two patients were analyzed. The overall complication rate after both stages was 23.9% on the therapeutic side and 16.5% on the prophylactic side. Infection was the most common complication on both sides. All infections on the prophylactic mastectomy side were successfully treated with intravenous (IV) antibiotics (salvage rate of 100%), whereas 35.7% of infected tissue expander/implants on the therapeutic mastectomy side were explanted despite treatment.ConclusionCareful counselling of patients undergoing elective contralateral prophylactic mastectomy is essential as complications can develop in either breast after reconstruction.  相似文献   
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