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Biomedical subjects

H C Hsu

Publications and source records attributed to H C Hsu.

At least 109 records · Page 6Linked to original sources
PubMed1999

Hypermethylation of the p16 gene in sporadic T3N0M0 stage colorectal cancers: association with DNA replication error and shorter survival.

Hypermethylation in the promoter region of the p16 gene was suspected to be involved in the tumorigenesis of colorectal cancers, although its clinical and biological significance remains obscure. In this study, we collected 84 T3N0M0 stage primary colorectal cancers that were curatively resected. The clinicopathologic data were reviewed. p16 hypermethylation was determined by a methylation-specific polymerase chain reaction (PCR). p53 overexpression was detected by immunocytochemistry (ICC). The point mutations in the 12 and 13 codons of the K-ras gene were screened by restriction enzyme analysis. Loss of heterozygosity (LOH) of the DCC (Deleted in Colorectal cancer) gene was examined by PCR using primers of the DCC (18q21) microsatellite marker. The DNA replication error (RER) was examined using 7 microsatellite markers at distinct chromosomal loci. p16 hypermethylation, regarded as an indication of p16 inactivation, was evident in 24 (28.6%) of the tumors. No correlation was found between p16 hypermethylation and various clinicopathologic factors, includinig age, sex, tumor location, tumor size, growth pattern, tumor differentiation, mucin production, vascular and/or lymphatic invasion, lymphocyte infiltration of the tumor, and serum level of carcinoembryonic antigen. There was no association between p16 hypermethylation of K-ras gene mutation, p53 overexpression and LOH of the DCC gene. However, p16 hypermethylation was significantly associated with DNA RER (p = 0.01). Survival analysis revealed a significant survival disadvantage of p16-hypermethylated versus non-p16-hypermethylated tumors (p = 0.0001). These findings indicate that p16 hypermethylation plays a role in the carcinogenesis of a subset of colorectal cancers; and the presence of p16 hypermethylation predicts shorter survival in T3N0M0 stage colorectal cancers.

Aged↗
PubMed1999

Regulation of Fas-mediated apoptosis in CD2-fas transgenic mice.

Fas-mediated apoptosis is an essential mechanism for maintenance of immune homeostasis. The expression of Fas is regulated at transcriptional and protein levels. Furthermore, several death domain molecules and caspases are crucial downstream mediators and executioners of Fas-mediated apoptosis. A tightly regulated interaction of these molecules ensures normal immune functions, including the execution of activation-induced cell death, T-cell mediated cytotoxicity, and surveillance of immune privileged tissues. In contrast, abnormally increased or decreased Fas-mediated apoptosis is a major pathogenic mechanism of several diseases, including systemic or tissue-specific autoimmune diseases and immune deficiency. Two CD2-fas transgenic mouse lines are described here to demonstrate the importance of controlling Fas-mediated apoptosis. Correction of Fas in Fas-mutant mice restored apoptosis function and ameliorated autoimmune symptoms, whereas a long-term enhancement of Fas expression in Fas-normal mice resulted in an increased acute-phase response and renal amyloidosis in aged transgenic mice.

Acute-Phase Reaction↗
PubMed1999

Polyamine-fas interactions: inhibition of polyamine biosynthesis in MRL-lpr/lpr mice is associated with the up-regulation of fas mRNA in thymocytes.

MRL-lpr/lpr is a strain of mice that develops spontaneous signs of the autoimmune disease, systemic lupus erythematosus (SLE or lupus). The lpr (lymphoproliferation) defect has been identified as an insertion of an early transposon (ETn) derived sequence into the fas apoptosis gene. We studied the in vivo effects of difluoromethylornithine (DFMO), an irreversible inhibitor of the polyamine biosynthetic enzyme, ornithine decarboxylase (ODC), on the expression of fas in MRL-lpr/lpr mice as well as in congenic MRL- + / + and autoimmune NZB/W strains. Using Northern blot hybridization and reverse transcription polymerase chain reaction (RT-PCR), we found that DFMO treatment resulted in an increase in the expression of fas mRNA in the thymus of MRL-lpr/lpr mice. Using RT-PCR, we further found that the increased expression of fas was associated with the suppression of chimeric ETn/fas mRNA. With fractionated CD4 + and CD8 + T cells, we found a cell-specific effect of DFMO on chimeric ETn/fas expression in CD8 + cells. ETn/fas expression was detected in CD8+ T cells from untreated mice, but it was eliminated after DFMO treatment. HPLC analysis of polyamines showed depletion of putrescine and partial reduction of spermidine (35%) in DFMO-treated mice compared to controls. These results indicate that DFMO-mediated polyamine depletion is linked to the regulation of fas and chimeric ETn/fas in MRL-lpr/lpr mice. Elevated levels of polyamines in this strain, as found in earlier studies, may be associated with the progression of the autoimmune disease by altering the expression of fas gene or by facilitating the expression of chimeric ETn/fas. Our data also provide new mechanistic insights into the beneficial effects of DFMO on these mice.

Animals↗
PubMed1999

Tissue hepatocyte growth factor and proliferating cell nuclear antigen in hepatocellular carcinoma.

To better understand the roles of hepatocyte growth factor (HGF) and proliferating cell nuclear antigen (PCNA) in hepatocellular carcinoma (HCC), 37 surgically resected HCCs and corresponding nontumorous liver tissue specimens were collected and the expression of these two factors was quantified by Western blot analysis. Both HGF and PCNA expression levels were significantly higher in tumor tissue than in nontumorous liver tissue. However, their expression levels in HCC tissue and nontumorous tissue did not show any significant correlation with the recurrence of HCC. In addition, HGF and PCNA did not correlate with Edmondson's grade, invasiveness of tumor, presence of tumor capsule, or tumor size. No correlation was found between the expression levels of HGF and PCNA in HCC tissue. We conclude that, although both HGF and PCNA are present at higher levels in HCC tissue than in nontumorous liver tissue, they play little role in the clinicopathologic manifestations of this tumor. HGF appears to contribute little, if at all, to the proliferative activity of HCC cells.

Adult↗
PubMed1999

Hyperinsulinemia and related atherosclerotic risk factors in the population at cardiovascular risk: a community-based study.

BACKGROUND: A population-based study was conducted in Taiwan to investigate the prevalence of insulin resistance and high serum insulin concentrations and their relationships with potential atherosclerotic risk factors. METHODS: We studied 2165 subjects, ages >35, from a community cohort. RESULTS: The distributions of fasting insulin were skewed to the right, with higher concentrations in women than in men. As age increased, insulin increased in women, but decreased in men. As fasting insulin concentrations increased, postloading insulin, glucose, blood pressure, body mass index, waist-to-hip ratio, total cholesterol, triglycerides, LDL-cholesterol, apoprotein B, plasminogen activator inhibitor 1, tissue plasminogen activator, and fibrinogen increased, but lipoprotein(a), HDL-cholesterol, and apoprotein A1 decreased. Multiple logistic regression showed that obesity, high LDL-cholesterol, and low HDL-cholesterol were significant predictors of hyperinsulinemic status. CONCLUSION: The study subjects with insulin resistance syndrome and related risk factors may be at risk for atherosclerosis, thrombosis, and other coronary heart diseases.

Age Factors↗
PubMed1999

Human recombinant DNA-derived antihemophilic factor (factor VIII) in the treatment of hemophilia A.

BACKGROUND: Plasma-derived factor VIII concentrates used in the treatment of hemophilia A have the potential danger of transfusion-associated viral disease. The safety and efficacy of a recombinant factor VIII preparation for the treatment of this disorder were evaluated in this study. METHODS: We compared the pharmacokinetics of plasma-derived and recombinant factor VIII in 12 previously treated subjects with severe hemophilia A. RESULTS: The recovery and elimination half-lives of the recombinant factor VIII were equal to those of plasma-derived factor VIII. It was well tolerated via parenteral therapy, and only two mild adverse reactions (5%) were reported. No evidence of new viral infection was noted during the study period with the recombinant factor VIII. CONCLUSIONS: The biologic activity of the recombinant factor VIII is comparable with that of plasma factor VIII concentrate. It is safe and efficacious for the treatment of hemophilia A.

Adult↗
PubMed1999

Radiation therapy in primary central nervous system lymphoma.

BACKGROUND: Treatment of primary central nervous system lymphoma (PCNSL) in Chinese individuals has rarely been reported. Therefore, this article presents our experience in managing PCNSL with radiotherapy. METHODS: A thorough review was made of the medical records of 13 patients diagnosed with PCNSL at Kaohsiung Chang Gung Memorial Hospital from 1988 through 1997. The clinical characteristics, treatment modalities, and results were analyzed as well. RESULTS: Thirteen patients diagnosed with PCNSL were identified, of which 10 cases originated in the brain whereas three were of spinal origin. Seven of the patients were man and six were women, with a mean age of 54.9 +/- 13.1 years (range 29 to 74 years). Diffuse large cell lymphoma (11 cases) was the most common histology. Limb weakness (11 cases) and headache (7 cases) were the most common complaints at presentation. Nine patients received radiation therapy alone and four patients received radiation therapy plus chemotherapy after surgical resection or biopsy. Follow-up computed tomography (CT) scans 3 to 4 months after the completion of radiotherapy revealed that nine patients (69%) had a complete response and four (31%) had a partial response. Local recurrence occurred in five patients (56%) treated with radiation therapy alone and in one patient (25%) treated with combined modalities. The overall actuarial survival rate was 54% at 2 years and 27% at 5 years. CONCLUSION: Results in this study indicate that the initial response to radiotherapy is satisfactory. However, a local relapse frequently occurs. Future considerations should focus on new modes of treatment, such as three-dimensional conformal radiation therapy for dose escalation or a combination of chemotherapy and radiotherapy.

Adult↗
PubMed1999

Apoptosis and cell death in the endocrine system.

Inflammatory diseases of the endocrine system--such as thyroiditis, diabetes, and Graves' disease--are considered to be autoimmune in origin. More recently, these and other autoimmune diseases have been associated with defects in Fas apoptosis. The mutation of the Fas or Fas ligand (FasL) has been observed in a minority of patients with autoimmune disease. However, dysfunction of the Fas apoptosis signaling pathway or production of soluble factors, including sFas and sFasL, may be more prevalent. Certain endocrine tissues, such as the testes, are immune privilege sites. Defects in Fas and FasL expression in immune privilege sites can trigger an inflammatory response. Other factors that trigger inflammatory diseases of the thyroid or islets may be loss of self tolerance, leading to an autoimmune response. An infectious trigger or other environmental agent can initiate organ damage, leading to release of new antigens that initiate the autoreactive process. We have developed a murine cytomegalovirus model of Sjögren's syndrome in which defects in the Fas/FasL pathway are necessary to enable chronic inflammation, even after the initial virus has been cleared. Another interaction between the endocrine system and apoptosis is by direct hormone interaction. This is exemplified by the orphan steroid receptor Nur77. Nur77 is important for T cell apoptosis after signaling through CD3. We have demonstrated that a dominant-negative Nur77 transgenic mouse exhibits a defect in thymic selection of T cells. Therefore, there are many potential mechanisms by which endocrine glands or hormones can affect the Fas apoptosis pathway, resulting in either cell death or a chronic inflammatory disease in the endocrine system, leading to hypothyroidism and diabetes. This inflammatory dysfunction can be reversed by a dominant-negative I kappa B that prevents nuclear translocation of NF-kappa B. We have developed antigen-specific, antigen-presenting cells that express high levels of FasL that can prevent tissue-specific inflammatory disease. Treatment with these cells prevents development of diabetes in NOD mice. Further understanding of the role and regulation of apoptosis in diseases of the endocrine system (e.g., diabetes, thyroiditis) should lead to better methods of treatment and prevention of these diseases.

Animals↗
PubMed1999

Prevalence of factor V Leiden in the Chinese population.

BACKGROUND: Thromboembolic diseases remain a major cause of morbidity and mortality in most countries. Factor V Leiden was found to be a major cause of thromboembolic disease in Western countries. Chinese have proved to be less prone to thromboembolic diseases, therefore investigation of the prevalence of factor V Leiden is necessary among a Chinese population. METHODS: From May, 1997, to April, 1998, a total of 1,261 subjects, including 420 healthy subjects, 719 patients with nonthrombotic hematologic disorders, 77 patients with diabetes mellitus and 45 patients with deep vein thrombosis, different in age and sex, were consecutively entered into our study to determine the prevalence of factor V Leiden in the Chinese population (mean age, 50.1 +/- 18.3 years; range, 1-99 years). Of this population, 873 were male and 388 were female. RESULTS: None of the subjects was found to have factor V Leiden mutation (Arg 506-Gln mutation). Activated protein C resistance was also measured in 827 patients; none of them had an activated protein C ratio of less than 2.0. CONCLUSIONS: We suggest that factor V Leiden mutation is rare among the Chinese.

Activated Protein C Resistance↗
PubMed1998

Impact of the extent of parametrial involvement in patients with carcinoma of the uterine cervix.

PURPOSE: A scoring system is proposed to measure the extent of parametrial involvement and predict treatment outcome in patients with carcinoma of the uterine cervix. METHODS AND MATERIALS: 244 patients with FIGO Stage IIB (n = 146) or IIIB (n = 98) carcinoma of the uterine cervix were treated by radical radiotherapy from October 1987 to June 1992. Impact of the extent of parametrial involvement on outcome was studied. All patients were scored by the newly introduced scoring system described as follows: score 1, tumor extending <1/2 the distance to the pelvic side wall; score 2, tumor extending >1/2 the distance to the pelvic side wall but not to pelvic side wall; score 3, tumor extending to the pelvic side wall. The score in each patient was defined as the sum of the scores of both the left and right parametrial tumor extent. RESULTS: There were 53, 47, 61, 34, 25, and 24 patients in score 1, 2, 3, 4, 5, and 6, respectively. All 244 patients were subdivided into three groups described as follows: score 1 and 2, group I; score 3 and 4, group II; score 5 and 6, group III. In univariate analysis, lower score groups had better overall survival rate (OS), disease-free survival rate (DFS), local control rate (LC), and distant metastasis-free rate (DMF) than higher score groups including groups I vs. II, II vs. III, or I vs. III. The differences were all statistically significant except for the difference of the DMF in group I vs. II. In multivariate analysis, score (range 1-6) was also statistically significant in OS (p < 0.0001), DFS (p = 0.0015), LC (p = 0.0032), and DMF (p = 0.0141). CONCLUSIONS: The data suggested that the new scoring system defined by pelvic examination is a convenient, simple, and reliable method of measuring the degree of parametrial extension and predicting the outcome of patients with parametrial disease.

Adult↗
PubMed1998

The influence of cryopreservation on cytokine production by human T lymphocytes.

Human T lymphocytes isolated from peripheral blood were cryopreserved at -196 degreesC for different periods of 3, 14, 21, 35, and 50 days. Viability and cytokine-producing activity of T cells were examined before and after cryopreservation. A high recovery (90 +/- 1%) of viable T cells was obtained at each frozen period, indicating that a 10% loss of cells was due to the freezing process rather than the duration of cryopreservation. There was no difference in cell cycle distribution between PHA-treated fresh and frozen lymphocytes. Resting human T cells produced little or no cytokine. After stimulation of fresh T cells with PHA, an apparent increase in cytokine production was noted in IL-2 (35.5 +/- 8.3 pg/ml), IL-6 (1280.4 +/- 64.7 pg/ml), tumor necrosis factor-alpha (874.3 +/- 71.7 pg/ml), interferon-gamma (58.9 +/- 2.2 pg/ml), and granulocyte macrophage-colony-stimulating factor (59.5 +/- 4.4 colonies/5 x 10(4) bone marrow cells). Compared with PHA-activated fresh T cells, all the above cytokines did not diminish in their levels in conditioned medium from PHA-treated frozen T cells thawed at each storage period, suggesting that cryopreservation could well retain the cytokine-producing activity of human T lymphocytes. In addition, our results also revealed that cryopreservation rendered T lymphocytes more responsive to PHA in IL-2 production than fresh T cells.

Cryopreservation↗
PubMed1998

Vitamin E supplementation attenuates myointimal proliferation of the abdominal aorta after balloon injury in diet-induced hypercholesterolemic rabbits.

The effects of vitamin E supplementation in a dose of 450 mg/1000 g chow on the myointimal proliferation of the abdominal aorta after balloon injury were studied in 4 groups of rabbits (24 each). The animals were fed regular diet, regular diet plus vitamin E, 1% cholesterol-enriched diet, and 1% cholesterol-enriched diet plus vitamin E. Each animal underwent a balloon injury of the abdominal aorta and left common iliac artery after 2 weeks of feeding. The animals remained on their respective diets thereafter. In 8 balloon-injured and 8 sham-operated animals of each group, the abdominal aortas were harvested 3 days after the procedure for the analysis of prostacyclin and thromboxane A2 synthesis, thiobarbituric acid reactive substances (TBARS) levels, enzyme activities of glutathione reductase (GR) and glutathione peroxidase (GP) as well as reduced (GSH) and oxidized (GSSG) glutathione levels, 3H-thymidine uptake, cholesterol as well as vitamin E contents. In the other 8 balloon-injured rabbits of each group, the tissue was harvested 3 weeks later for the morphometric study. In dependent of high cholesterol feeding, the vitamin E-treated rabbits had lower aortic production of thromboxane B2, higher 6-keto-PGF1 alpha and higher 6-keto-PGF1 alpha/thromboxane B2 ratios in both procedures. The aortic TBARS levels of the rabbits treated high cholesterol alone were significantly higher than the other three groups in both procedures. Balloon injury had a trend to increase TBARS levels and had significantly higher 3H-thymidine uptake (each p < 0.001) than sham operation in each group. Vitamin E supplement to high cholesterol diet or regular chow reduced aortic TBARS levels (p < 0.005 and 0.01, respectively) and 3H-thymidine uptake (p < 0.05 and 0.01, respectively), as well as attenuated myointimal proliferation of the abdominal aorta and left common iliac artery after balloon injury; but only supplement to high cholesterol diet reached statistical significances (both p < 0.05 compared to rabbits fed high cholesterol alone). These results suggest that vitamin E supplement changes prostanoid metabolism to a favorable pattern and reduces lipid peroxidation of the abdominal aortic wall, thus attenuates myointimal proliferation after balloon injury; these presentations are particularly obvious in diet-induced hypercholesterolemic rabbits.

6-Ketoprostaglandin F1 alpha↗
PubMed1998

Evaluation of metal ion release and corrosion resistance of ZrO2 thin coatings on the dental Co-Cr alloys.

OBJECTIVES: The aim of this study was to determine if electrolytic ZrO2 thin coatings increased the corrosion resistance and decreased the metal ion release of dental cobalt-chromium alloys. METHODS: Dental Co-Cr alloys were electrolytically deposited with ZrO2 ceramic coatings using a 0.0625 M ZrO(NO3)2 solution, at various potentials, for 500 s. The electrolytic ZrO2 gel-coated specimens were annealed at 723 K for 1 h in air. Scanning electron microscopy (SEM) was used to observe the morphology of the ZrO2 ceramic coatings on Co-Cr alloys. A dynamic polarization test was used to compare the corrosion resistance of the ZrO2 coated and uncoated Co-Cr alloys in artificial saliva. Metal ion concentrations were determined with graphite furnace atomic absorption spectroscopy (AAS). RESULTS: The SEM micrographs showed that the Co-Cr alloy can be coated with zirconia oxide at -0.7 V more homogeneously and more completely than at -1.5 V. The polarization curves indicated that the ZrO2 coating on Co-Cr alloys annealed at 723 K for 1 h in air exhibited better corrosion resistance in artificial saliva. The results of the AASs showed that the ZrO2-coated Co-Cr alloys decreased chromium ion release levels, as compared with the uncoated Co-Cr alloys. The scratch test indicated a good bond strength between the ZrO2 and Co-Cr alloy. SIGNIFICANCE: The electrolytically deposited ZrO2 coatings on Co-Cr alloys may improve the corrosion resistance and decrease the release of metal ions. It is suggested that the electrolytic ZrO2 coating method could have a widespread application in dentistry in the future.

Chromium↗
PubMed1998

Association of downregulation of cyclin D1 and of overexpression of cyclin E with p53 mutation, high tumor grade and poor prognosis in hepatocellular carcinoma.

BACKGROUND/AIMS: The major regulatory events leading to cell proliferation occur in the G1 phase of cell cycle, and the deranged expression of G1 cyclins is related to oncogenesis. In this study, we analyzed the aberrant expressions of cyclins D1 and E, and their role in hepatocellular carcinoma. METHODS: We examined paired hepatocellular carcinoma and liver RNAs taken from 71 patients who had been followed for more than 4 years after tumor resection, using reverse transcription-polymerase chain reaction supplemented with Northern blotting and immunohistochemistry. The genetic alterations of the p53 gene were also studied. RESULTS: Downregulation of cyclin D1 mRNA was detected in 29 hepatocellular carcinomas (40.8%), while overexpression was detected in only 4 hepatocellular carcinomas (5.6%). Downregulation of cyclin D1 was associated significantly with large hepatocellular carcinomas (p=0.0006) and poorly differentiated (grades III-IV) hepatocellular carcinoma (p=0.057), but not seen in any of 15 minute hepatocellular carcinomas (< or =2.5 cm in size). Cyclin E mRNA was overexpressed in 40 hepatocellular carcinomas, regardless of tumor size. Overexpression of cyclin E was significantly associated with poorly differentiated and invasive hepatocellular carcinoma (p=0.001 and p=0.015, respectively). Downregulation of cyclin D1 and overexpression of cyclin E were significantly associated with the p53 mutation (p=0.023 and p=0.005, respectively). Hepatocellular carcinomas expressing both downregulation of cyclin D1 and overexpression of cyclin E had the worst 4-year survival (p<0.03), and higher frequencies of the p53 mutation (p<0.001), large hepatocellular carcinoma (p<0.001), and invasive tumor (p<0.01). CONCLUSIONS: The deranged expressions of G1 cyclins correlate with the p53 mutation, tumor progression, and tumor biologic behavior of hepatocellular carcinoma. Overexpression of cyclin E occurs early, and downregulation of cyclin D1 late in hepatocellular carcinoma growth.

Carcinoma, Hepatocellular↗
PubMed1998

Determinative role of peroxidized low-density lipoprotein in myocardial thromboxane synthesis during pacing-induced ischaemia in humans.

1. Myocardial thromboxane A2 production increases in patients with pacing-induced ischaemia and correlates with a decrease in myocardial lactate extraction. The release of myocardial thromboxane A2 before any lactate production was observed in patients with unstable angina. This study was proposed to clarify whether the early thromboxane A2 release contributed to the ongoing myocardial ischaemia and to determine which metabolites can be attributed to the thromboxane A2 release. Thirty-five patients with chest pain and positive treadmill exercise test underwent atrial pacing to the predicted maximal heart rate. The pacing was maintained at this peak rate for 10 min, then ceased. Blood samples of the ascending aorta and coronary sinus were drawn simultaneously at rest, at 2 and 10 min of peak-pacing, and 5 and 10 min after termination of the pacing; samples were used for analyses of lipid profiles, prostacyclin, thromboxane A2, lactate and lipid peroxides on plasma and low-density lipoprotein particles. 2. Twenty out of 35 patients who displayed pacing-induced ischaemia were documented by electrocardiographic evidence of ST depression > 2 mm developing after 2 min of peak-pacing [ischaemic group, ST delta(+)]. They had (i) negative fractional lactate extraction; (ii) pacing-induced decreases of plasma thromboxane A2 levels in the coronary sinus blood (564 +/- 57 versus 479 +/- 47 ng/l, P < 0.05) at 2 min of peak-pacing; the data increased at 10 min of peak-pacing (564 +/- 57 versus 620 +/- 60 ng/l, P < 0.05), then returned to baseline levels at 5 and 10 min post-pacing; (iii) significantly increased lipid peroxides on low-density lipoprotein of the coronary sinus blood at 2 and 10 min of peak-pacing (each P < 0.001), as well as at 5 min post-pacing (P < 0.05); (iv) significant correlation between thromboxane A2 levels and lipid peroxides on low-density lipoprotein of the coronary sinus blood samples. 3. In ST delta(+) patients, myocardial thromboxane synthesis changed before lactate production and correlated with the increase of lipid peroxides on low-density lipoprotein of the coronary venous blood. This implies that lipid peroxides on low-density lipoprotein participate in thromboxane production and play a determinative role in pacing-induced ischaemia.

Analysis of Variance↗
PubMed1998

Cerebral air embolism complicating bilevel positive airway pressure therapy.

A 13 yr old male with acute lymphoblastic leukaemia who received bilevel positive airway pressure ventilation via a face mask for post-transplant pneumonitis developed subcutaneous emphysema, radiographic evidence of pulmonary interstitial emphysema, pneumomediastinum and 6 h later, right hemiparesis and focal livedo reticularis. This case illustrates that severe barotrauma may complicate noninvasive bilevel positive airway pressure ventilation.

Adolescent↗