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Abstract As the risk of gypsy moth outbreaks that have detrimental effects on forest ecosystem in the Northern Hemisphere increase due to climate change, a quantitative evaluation of the impact of gypsy moth defoliation is needed to support the adaptive forest management. To evaluate the host-specific impact of gypsy moth defoliation, radial growth and annual carbon accumulation were compared for one severely defoliated (Larix kaempferi (Lamb.) Carrière) and one moderate defoliated (Quercus acutissima Carruth.) host, in defoliated and non-defoliated site using tree-ring analysis. Finally, the resilience indices of radial growth variables were calculated to assess the ability of sampled trees to withstand defoliation. Gypsy moth defoliation mainly decreased latewood width and caused reduction in annual carbon absorption more than 40% for both tree species. However, L. kaempferi, showed the reduced growth until the year following defoliation, while Q. acutissima, showed no lagged growth depression and rapid growth recover. The findings show how each species reacts differently to gypsy moth defoliation and highlight the need of managing forests in a way that takes resilient tree species into account.

It is crucial to evaluate the effects of thinning on litterfall production, soil chemical properties, and fine root dynamics when implementing thinning as a silvilcultural technique to enhance tree growth and timber yield in Pinus koraiensis plantations. Thus, we determined the 10-year effects (2007–2017) of different thinning intensities on litterfall production, soil chemical properties, and fine root biomass and necromass within a P. koraiensis plantation in South Korea. The soil chemical parameters and fine root biomass and necromass were also compared across three soil depths (0–10, 10–20, and 20–30 cm). Three thinning treatments were employed: no thinning (CON), light thinning (32% removed, LT), and heavy thinning (64% removed, HT). Results revealed that litterfall was consistent across all thinning treatments, but broadleaf species had considerably higher litterfall production at HT stands than at CON/LT stands. Soil chemical properties, except exchangeable K+, were generally lower at LT stands, particularly at a depth of 20–30 cm soil. After ten years, there was a decrease in fine root biomass and necromass with increasing soil depth. Over 80% of fine roots were found in the upper layer (0–20 cm), while very fine roots (0–1 mm) consisted mainly of 47% pine and 53% other species and were concentrated in the 0–10 cm soil depth in HT. In conclusion, different thinning intensities had diverse effects on the parameters measured within the plantation. Future studies can explore how the effects of thinning intensities on litterfall production, soil chemistry, and fine root dynamics affect species diversity, carbon storage, and understory vegetation in P. koraiensis plantations.

We examined the influence of climate and habitat changes on the occurrence of butterflies in South Korea, using data recorded in two different periods: (i) past (1938–1950) and (ii) present (1996–2011). Butterfly species were classified according to their distribution types (northern, southern, and miscellaneous) to examine the effect of climate change. They were also classified according to three different habitat types (forest interior, forest edge, and grassland) to examine the effect of habitat change. Three types of food niche (monophagous, oligophagous, and polyphagous) were identified. A community temperature index (CTI), based on the species temperature index of each species, was calculated for past and present butterfly communities to estimate range shifts of butterflies at the community level. At the species level, range shifts of butterflies were calculated as a shift of the mid-zone of the distribution range in terms of latitude and temperature. The results showed that a change in the occurrence of butterflies was not significantly different among the three distribution types. The CTIs were not different between past and present communities, and the mid-zones of distribution range in latitude and temperature did not change. These results indicate that the occurrence change of butterflies was not significantly influenced by climate change but was instead influenced by habitat change from bare-ground or grassland to forests over 60 years. There was an increase in forest species and a decrease in grassland species, reflecting the effects of large-scale reforestation in South Korea over the last few decades. The reforestation has resulted in an increase in monophagous (oak-feeding) butterflies. Our results show that habitat change played a key role in the occurrence of Korean butterflies and may be confounding any possible influence of climate change.

The role of forests is increasing because of rapid land use changes worldwide that have implications on ecosystems and the carbon cycle. Therefore, it is necessary to obtain accurate information about forests and build forest inventories. However, it is difficult to assess the internal structure of the forest through 2D remote sensing techniques and fieldwork. In this aspect, we proposed a method for estimating the vertical structure of forests based on full-waveform light detection and ranging (FW LiDAR) data in this study. Voxel-based tree point density maps were generated by estimating the number of canopy height points in each voxel grid from the raster digital terrain model (DTM) and canopy height points after pre-processing the LiDAR point clouds. We applied an unsupervised classification algorithm to the voxel-based tree point density maps and identified seven classes by profile pattern analysis for the forest vertical types. The classification accuracy was found to be 72.73% from the validation from 11 field investigation sites, which was additionally confirmed through comparative analysis with aerial images. Based on this pre-classification reference map, which is assumed to be ground truths, the deep neural network (DNN) model was finally applied to perform the final classification. As a result of accuracy assessment, it showed accuracy of 92.72% with a good performance. These results demonstrate the potential of vertical structure estimation for extensive forests using FW LiDAR data and that the distinction between one-storied and two-storied forests can be clearly represented. This technique is expected to contribute to efficient and effective management of forests based on accurate information derived from the proposed method.

Remote ischemic preconditioning (RIPC) induces transient episodes of ischemia by the occlusion of blood flow in non-target tissue, before a subsequent ischemia-reperfusion injury. When RIPC is applied before percutaneous coronary intervention (PCI), the kidneys may be protected against ischemia-reperfusion injury and subsequently contrast-induced acute kidney injury (CI-AKI). The aim of this study was to evaluate the efficacy of RIPC for the prevention of CI-AKI in patients with diabetes with pre-existing chronic kidney disease (CKD) undergoing elective PCI.This randomized, double-blind, sham-controlled study enrolled patients with diabetes scheduled for elective PCI with eGFR ≤60 ml/min/1.73 m2 or urinary albumin creatinine ratio of >300 mg/g to receive either RIPC or the sham ischemic preconditioning.One hundred and two patients (68.9 ± 8.2 years old, 47.1% men) were included. Baseline eGFR, creatinine and serum NGAL was similar between RIPC and control groups (48.5 ± 12 ml/min vs. 46.6 ± 10 ml/min, p = 0.391; 1.42 ± 0.58 mg/dl vs. 1.41 ± 0.34 mg/dl, p = 0.924; and 136.0 ± 45.0 ng/ml vs. 137.6 ± 43.3 ng/ml, p = 0.961, respectively). CI-AKI occurred in 13.7% (14/102) of the total subjects, with both RIPC and control groups having an equal incidence of 13.7% (7/51). No significant differences were seen in creatinine, NGAL, cardiac enzymes (troponin T, CKMB) and hs-CRP between the groups post-procedure.In this study, RIPC applied prior to elective PCI was not effective in preventing CI-AKI in patients with diabetes with pre-existing CKD.ClinicalTrials.gov NCT02329444.

Renal renin-angiotensin system (RAS) activation is one of the important pathogenic mechanisms in the development of diabetic nephropathy in type 2 diabetes. The aim of this study was to investigate the effects of a sodium-glucose co-transporter 2 (SGLT-2) inhibitor, dapagliflozin, on renal RAS in an animal model with type 2 diabetes.Dapagliflozin (1.0 mg/kg, OL-DA) or voglibose (0.6 mg/kg, OL-VO, diabetic control) (n = 10 each) was administered to Otsuka Long-Evans Tokushima Fatty (OLETF) rats for 12 weeks. We used voglibose, an alpha-glucosidase inhibitor, as a comparable counterpart to SGLT2 inhibitor because of its postprandial glucose-lowering effect without proven renoprotective effects. Control Long-Evans Tokushima Otsuka (LT) and OLETF (OL-C) rats received saline (n = 10, each). Changes in blood glucose, urine albumin, creatinine clearance, and oxidative stress were measured. Inflammatory cell infiltration, mesangial widening, and interstitial fibrosis in the kidney were evaluated by histological analysis. The effects of dapagliflozin on renal expression of the RAS components were evaluated by quantitative RT-PCR in renal tissue.After treatment, hyperglycemia and urine microalbumin levels were attenuated in both OL-DA and OL-VO rather than in the OL-C group (P < 0.05). The urine angiotensin II (Ang II) and angiotensinogen levels were significantly decreased following treatment with dapagliflozin or voglibose, but suppression of urine Ang II level was more prominent in the OL-DA than the OL-VO group (P < 0.05). The expressions of angiotensin type 1 receptor and tissue oxidative stress markers were markedly increased in OL-C rats, which were reversed by dapagliflozin or voglibose (P < 0.05, both). Inflammatory cell infiltration, mesangial widening, interstitial fibrosis, and total collagen content were significantly increased in OL-C rats, which were attenuated in OL-DA group (P < 0.05).Dapagliflozin treatment showed beneficial effects on diabetic nephropathy, which might be via suppression of renal RAS component expression, oxidative stress and interstitial fibrosis in OLETF rats. We suggest that, in addition to control of hyperglycemia, partial suppression of renal RAS with an SGLT2 inhibitor would be a promising strategy for the prevention of treatment of diabetic nephropathy.

BACKGROUND: Loss of ovarian function is highly associated with an elevated risk of metabolic disease. Monocyte chemoattractant protein-1 (MCP-1, C-C chemokine ligand 2) plays critical roles in the development of inflammation, but its role in ovariectomy (OVX)-induced metabolic disturbance has not been known. METHODOLOGY AND PRINCIPAL FINDINGS: We investigated the role of MCP-1 in OVX-induced metabolic perturbation using MCP-1-knockout mice. OVX increased fat mass, serum levels of MCP-1, macrophage-colony stimulating factor (M-CSF), and reactive oxygen species (ROS), whereas MCP-1 deficiency attenuated these. OVX-induced increases of visceral fat resulted in elevated levels of highly inflammatory CD11c-expressing cells as well as other immune cells in adipose tissue, whereas a lack of MCP-1 significantly reduced all of these levels. MCP-1 deficiency attenuated activation of phospholipase Cγ2, transforming oncogene from Ak strain, and extracellular signal-regulated kinase as well as generation of ROS, which is required for up-regulating CD11c expression upon M-CSF stimulation in bone marrow-derived macrophages. CONCLUSIONS/SIGNIFICANCE: Our data suggested that MCP-1 plays a key role in developing metabolic perturbation caused by a loss of ovarian functions through elevating CD11c expression via ROS generation.

Genetic testing is recommended for all patients with pheochromocytomas and paragangliomas (PPGL) to establish genotype–phenotype associations. We investigated germline mutations in 59 patients with PPGL at six Korean university hospitals using next-generation sequencing (NGS) targeting 38 PPGL-associated genes, including those recommended by the Korean PPGL Task Force. Germline mutations were identified in 13 patients (22%), and affected four genes: RET, NF1, VHL, and SDHD. Germline mutations were significantly associated with a family history of PPGL, smaller tumor size, and the presence of other types of tumors. Using 95 Korean PPGL cases with germline mutations identified through a literature review and 13 cases from our cohort, we characterized genotype–phenotype correlations. Mutation hotspots were identified in specific codons of RET (codons 631 and 634), VHL (157 and 167), and SDHB (131 and 253). NF1 mutations varied, indicating the absence of common hotspots. These findings highlight the efficacy of the recommended NGS panel for Korean patients with PPGL and the importance of genetic testing in establishing clinical management and personalized therapeutic strategies. [ABSTRACT FROM AUTHOR]

BackgroundThere is limited information regarding the optimal third-line therapy for managing type 2 diabetes mellitus (T2DM) that is inadequately controlled using dual combination therapy. This study assessed the efficacy and safety of pioglitazone or glimepiride when added to metformin plus alogliptin treatment for T2DM.MethodsThis multicenter, randomized, active-controlled trial (ClinicalTrials.gov: NCT02426294) recruited 135 Korean patients with T2DM that was inadequately controlled using metformin plus alogliptin. The patients were then randomized to also receive pioglitazone (15 mg/day) or glimepiride (2 mg/day) for a 26-week period, with dose titration was permitted based on the investigator's judgement.ResultsGlycosylated hemoglobin levels exhibited similar significant decreases in both groups during the treatment period (pioglitazone: −0.81%, P

This scoping review aimed to explore the characteristics of neonatal palliative care in the neonatal intensive care unit, including the features, contents, and experiences of infants, parents, and nurses during palliative care. Five databases (PubMed, Cochrane, CINAHL, Research Information Sharing Service, and Korean Studies Information Service System) were searched to identify relevant articles published between 2011 and 2020. From the systematic search and review process, 13 studies that met the eligibility criteria were selected for the analysis. From the literature review, 2 key principles were found to facilitate neonatal palliative care: family-centered care and integrative care in the neonatal intensive care unit. In addition, the themes found in this review included (1)providing comfortable care to dying infants with respect to infants and offering parents choices, (2) therapeutic communication, (3) support with respect, and (4) bereavement care for parents of dying infants in the neonatal intensive care unit. Caregivers require effective communication, manpower support, emotional support, educational programs, and well-defined protocols. The evidence mapped and synthesized in this review indicates the need to facilitate the provision of palliative care in the neonatal intensive care unit in line with the unique needs of infants, parents, and nurses. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to develop a direct breastfeeding protocol for premature infants admitted to neonatal intensive care units (NICUs) and investigate its efficacy. Background: Direct breastfeeding increases the amount and duration of breastfeeding. However, NICUs have low direct feeding rates owing to medical staff anxiety, lack of knowledge and experience, and fear of overwork. Accordingly, this study developed a protocol for direct breastfeeding in the NICU and evaluated its effect. Methods: The protocol was developed through a literature review, expert validation, and preliminary investigation. Its application effects were identified using a nonexperimental, evidence-based research design targeting premature infants, their mothers, and NICU nurses. Results: The protocol comprised 5 areas and 23 items. Application of the protocol resulted in continuous weight gain of the infants and increased self-efficacy in the mothers' direct breastfeeding (t = 3.219, P = .004). Significant increases were noted in NICU nurses' direct breastfeeding activities (t = 3.93, P < .001), breastfeeding rates in the NICU (P = .037), and direct breastfeeding rates (P = .007). Conclusions: Results underscore the value of an evidence-based protocol for improving breastfeeding rates in premature infants. This study highlights the need for continuous nursing education on protocol applications and human resource support. [ABSTRACT FROM AUTHOR]

Background: This study investigates the long-term efficacy and safety of evogliptin add-on therapy in patients with inadequately controlled type 2 diabetes mellitus (T2DM) previously received dapagliflozin and metformin (DAPA/MET) combination. Methods: In this multicenter randomized placebo-controlled phase 3 trial, patients with glycosylated hemoglobin (HbA1c) levels 7.0% to 10.5% (n=283) previously used DAPA 10 mg plus MET (=1,000 mg) were randomly assigned to the evogliptin 5 mg once daily or placebo group (1:1). The primary endpoint was the difference in the HbA1c level from baseline at week 24, and exploratory endpoints included the efficacy and safety of evogliptin over 52 weeks (trial registration: ClinicalTrials.gov NCT04170998). Results: Evogliptin add-on to DAPA/MET therapy was superior in HbA1c reduction compared to placebo at weeks 24 and 52 (least square [LS] mean difference, -0.65% and -0.55%; 95% confidence interval [CI], -0.79 to -0.51 and -0.71 to -0.39; P<0.0001). The proportion of patients achieving HbA1c <7% was higher in the triple combination group at week 52 (32.14% vs. 8.51% in placebo; odds ratio, 5.62; P<0.0001). Evogliptin significantly reduced the fasting glucose levels and mean daily glucose levels with improvement in homeostatic model assessment of ß-cell function (LS mean difference, 9.04; 95% CI, 1.86 to 16.21; P=0.0138). Adverse events were similar between the groups, and no serious adverse drug reactions were reported in the evogliptin group. Conclusion: Long-term triple combination with evogliptin added to DAPA/MET showed superior HbA1c reduction and glycemic control compared to placebo at 52 weeks and was well tolerated. [ABSTRACT FROM AUTHOR]

Objectives: Controlling blood pressure is a key step in reducing cardiovascular mortality in older adults. Gender differences in patients’ attitudes after disease diagnosis and their management of the disease have been identified. However, it is unclear whether gender differences exist in hypertension management among older adults. We hypothesized that gender differences would exist among factors associated with hypertension diagnosis and control among community-dwelling, older adults. Methods: This cross-sectional study analyzed data from 653 Koreans aged ≥60 years who participated in the Korean Social Life, Health, and Aging Project. Multiple logistic regression was used to compare several variables between undiagnosed and diagnosed hypertension, and between uncontrolled and controlled hypertension. Results: Diabetes was more prevalent in men and women who had uncontrolled hypertension than those with controlled hypertension or undiagnosed hypertension. High body mass index was significantly associated with uncontrolled hypertension only in men. Multiple logistic regression analysis indicated that in women, awareness of one’s blood pressure level (odds ratio [OR], 2.86; p=0.003) and the number of blood pressure checkups over the previous year (OR, 1.06; p=0.011) might influence the likelihood of being diagnosed with hypertension. More highly educated women were more likely to have controlled hypertension than non-educated women (OR, 5.23; p=0.013). Conclusions: This study suggests that gender differences exist among factors associated with hypertension diagnosis and control in the study population of community-dwelling, older adults. Education-based health promotion strategies for hypertension control might be more effective in elderly women than in elderly men. Gender-specific approaches may be required to effectively control hypertension among older adults.

Invasion and metastasis are important hallmarks of breast cancer and are the leading cause of patient mortality. Triple-negative breast cancer (TNBC) is an aggressive type of breast cancer characterized by a poor prognosis and a lack of effective targeted therapies. The present study investigated the inhibitory effect of a novel FTY720 derivative on the invasive phenotype of TNBC cells. Here, we showed that a novel compound with an isoxazole ring, 4-(3-Decylisoxazol-5-yl)-1-hydroxy-2-(hydroxymethyl)butan-2-aminium chloride (CM2-II-173), significantly inhibited invasiveness of MDA-MB-231 TNBC cells. Expression of matrix metalloproteinase (MMP)-9 and invasiveness of MCF10A normal breast cells induced by sphingosine-1-phosphate (S1P) were reduced by CM2-II-173 treatment. Activations of pMEK1, pAkt, pERK, and p38 MAPK by S1P were inhibited by treatment with CM2-II-173. Proliferation and anchorage-independent growth of MDA-MB-231 TNBC cells were significantly decreased by CM2-II-173. CM2-II-173 efficiently induced apoptosis in MDA-MB-231 TNBC cells. CM2-II-173 significantly inhibited invasive phenotypes of breast, liver, prostate, and ovarian cancer cells. CM2-II-173 exhibited a more potent effect on the invasiveness of MDA-MB-231 TNBC cells compared to FTY720. Taken together, this study demonstrated that CM2-II-173 has the potential to be a lead compound that can inhibit cancer progression of not only TNBC cells, but also of liver, prostate, and ovarian cancer cells. [ABSTRACT FROM AUTHOR]