Biomedical subjects

S C Yu

Publications and source records attributed to S C Yu.

At least 37 records · Page 2Linked to original sources

PubMed2000

Performance of enlarged blood pump models with five different impellers.

In earlier studies, a 5:1 enlarged pump model of the Kyoto-NTN Magnetically Suspended Centrifugal Blood Pump had been constructed and the flow characteristics investigated. Although the results obtained were satisfactory, the medium used was air. A 5:1 enlarged pump model using water as the medium thus was designed and constructed. Five different impeller blade profile designs were used in the present study. By varying (1) the blade profile design: forward, radial, and backward, (2) the number of blades used, and (3) the rotating speed, the flow characteristics of the pump were investigated. It was found that the impeller with the higher number of blades, used in the forward and straight blade profiles, have the best performance.

Animals↗

PubMed2000

Measurements of enlarged blood pump models using Laser Doppler Anemometer.

In an earlier study (Chua et al., 1998, 1999a), a 5:1 enlarged model of the Kyoto-NTN Magnetically Suspended Centrifugal Blood Pump (Akamatsu et al., 1995) with five different impeller blade profiles was designed and constructed. Their respective flow characteristics with respect to (1) the three different blade profile designs: forward, radial, and backward, (2) the number of blades used, and (3) the rotating speed were investigated. Among the five impeller designs, the results obtained suggested that impellers A and C designs should be adopted if higher head is required. Impellers A and C therefore were selected for the flow in between their blades to be measured using Laser Doppler Anemometer (LDA), so as to have a better understanding of the flow physics with respect to the design parameters.

Equipment Design↗

PubMed2000

Effect of ginsenoside on IL-1 beta and IL-6 mRNA expression in hippocampal neurons in chronic inflammation model of aged rats.

AIM: To study the effects of ginseng root saponins (GRS) on interleukin-1 beta (IL-1 beta) and interleukin-6 (IL-6) expression in hippocampal neurons in chronic inflammation model of aged rats. METHODS: Chronic inflammation was induced by consecutive intraperitioneal injections of bacterial lipopolysaccharides (LPS) in aged rats. The semiquantitative reverse transcription-polymerase chain reaction (RT-PCR) was used for determination of IL-1 beta and IL-6 mRNA in hippocampal neurons of aged rats. RESULTS: No marked expression of IL-1 beta and IL-6 mRNA was found in hippocampal neurons of young rats (3 months). In adult rats (9 months) the levels of IL-1 beta and IL-6 expressed were 1.54 +/- 0.21 and 1.63 +/- 0.21, respectively; in aged rats (24 months) treated with LPS the levels were 1.98 +/- 0.21 and 1.91 +/- 0.11 respectively, significantly higher than those of adult rats. After treatment with GRS (10, 20, 40 mg/kg), the IL-1 beta and IL-6 mRNA content in aged rats decreased markedly. CONCLUSION: The levels of IL-1 beta and IL-6 mRNA in hippocampal neurons increased with aging. GRS exerted inhibitory effects on IL-1 beta and IL-6 gene expression in chronic inflammation model of aged rats.

Aging↗

PubMed2000

[Detection of circulating antigen in urine from mice infected with Toxoplasma tachyzoites by SPA-ELISA].

OBJECTIVE: To explore a simple and convenient immunoassay for early diagnosis of Taxoplasma infection. METHODS: Urine samples collected from three groups of mice infected with different doses of tachyzoites were detected for Taxoplasma circulating antigen (TCA) by dot-ELISA using HRP-SPA as a second antibody (SPA-ELISA). RESULTS: Taxoplasma circulating antigens were detected in all three groups of infected mice in contrast with the normal control group. Taxoplasma circulating antigen was detected on d6 and d3 after infection in mice of light- and moderate-infection groups, respectively. CONCLUSION: SPA-ELISA is a simple and convenient method for early immunodiagnosis of recent Taxoplasma infection.

Animals↗

PubMed1999

Adjuvant intra-arterial iodine-131-labelled lipiodol for resectable hepatocellular carcinoma: a prospective randomised trial.

BACKGROUND: Resection of hepatocellular carcinoma is potentially curative, but local recurrence is common. In this prospective randomised trial, we aimed to find out if one dose of postoperative adjuvant intra-arterial iodine-131-labelled lipiodol could reduce the rate of local recurrence and increase disease-free and overall survival. METHODS: Patients who underwent curative resection for hepatocellular carcinoma and recovered within 6 weeks were randomly assigned one 1850 MBq dose of 131I-lipiodol or no further treatment (controls). We compared rates of recurrence and disease-free and overall survival (the primary endpoints) between the two groups by intention to treat. We planned an interim analysis when 30 patients (both groups together) had been followed up for a median of 2 years, with the intention of stopping early if the between-group difference in disease-free survival was significant (p=0.029). FINDINGS: Between April, 1992, and August, 1997, we recruited 43 patients: 21 received intra-arterial 131I-lipiodol and 22 received no adjuvant treatment. During a median follow-up of 34.6 (range 14.1-69.7) months, there were six (28.5%) recurrences among the 21 patients in the adjuvant treatment, compared with 13 (59%) in the controls (p=0.04). Median disease-free survival in the treatment and control groups was 57.2 (0.4-69.7) and 13.6 (2.1-68.3) months, respectively (p=0.037). 3-year overall survival in the treatment and control groups was 86.4% and 46.3%, respectively (p=0.039). The interim analysis showed a significant increase in disease-free survival in the treatment group compared with the controls (p=0.01), so we closed the trial early. 131I-lipiodol had no significant toxic effects. INTERPRETATION: In patients with hepatocellular carcinoma, one 1850 MBq dose of intra-arterial 131I-lipiodol given after curative resection significantly decreases the rate of recurrence and increases disease-free and overall survival.

Adolescent↗

PubMed1999

Percutaneous cholecystostomy and endoscopic cholecystolithotripsy in the management of acute cholecystitis.

BACKGROUND: Percutaneous cholecystostomy is a valuable alternative temporary measure for acute cholecystitis in elderly patients with severe underlying cardiopulmonary disease, but the subsequent management of gallbladder calculi is still controversial. METHODS: Eleven patients treated with percutaneous endoscopic cholecystolithotripsy after percutaneous cholecystostomy were evaluated retrospectively. RESULTS: All patients showed clinical improvement after percutaneous cholecystostomy. Tract dilation succeeded in 9 patients. Complete stone clearance was achieved in seven patients over one to four sessions (average, two sessions). Stone extraction could not be completed in two patients because gallbladder access was lost in one patient, and the other refused further procedure. There were three complications, with two biliary fistulas and one major bile leakage leading to emergency cholecystectomy. The duration of the entire procedure ranged from 30 to 126 days (mean, 58 days). During the follow-up (mean 17.2 months), one patient had recurrent cholangitis and the others remained asymptomatic. CONCLUSIONS: Percutaneous cholecystolithotripsy after percutaneous cholecystostomy is a safe alternative in the management of high-risk elderly patients with acute cholecystitis.

Acute Disease↗

PubMed1999

Percutaneous vertebral biopsy through intact bone: a coaxial bone transgressing technique with 18 gauge needle.

Advancement of radiologic technologies allows the detection of vertebral lesions at an earlier stage, thereby increasing the proportion of vertebral lesions that are surrounded by intact bone when they are detected. While biopsy guns are effective in obtaining good-quality tissue samples of osteolytic bone lesions, lesions that are covered by intact bone are not accessible with a biopsy gun. For percutaneous biopsy of osteolytic vertebral lesions, an intact-bone transgressing technique is described in which a simple, inexpensive and small-calibre (18-gauge) instrument is used to allow multiple passage of 20-gauge biopsy guns for effective tissue sampling. In this series consisting of metastatic and myeloproliferative lesions, the effectiveness and safety of this well-tolerated technique are demonstrated in thoracic and lumbar vertebrae.

Biopsy, Needle↗

PubMed1999

A steady flow analysis on the stented and non-stented sidewall aneurysm models.

As part of a general investigation on the effects of blood flow patterns in sidewall aneurysm, in vitro steady flow studies on rigid aneurysm models have been conducted using Particle Image Velocimetry over a range of Reynolds number from 200 to 1600. Above Reynolds number 700, one large recirculating vortex would be formed, occupying the entire aneurysmal pouch. The centre of the vortex is located at region near to the distal neck. A pair of counter rotating vortices would however be formed at Reynolds numbers below 700. For all the aneurysm models considered, the vortex strength, in general, is stronger at higher Reynolds numbers but lower at larger aneurysm size. Maximum strength of the vortex is about 15% of the bulk mean velocity in the upstream parent tube. Estimates of the wall shear stresses are derived from the near wall velocity measurements. Highest level of wall shear stresses always appears at the distal neck of the aneurysmal pouch. Stents and springs of different porosity have been used to dampen the flow movement inside the aneurysm so as to induce the possible formation of thrombosis. It is found that the flow movement inside the aneurysmal pouch can be suppressed to less than 5% of the bulk mean velocity by both devices. Furthermore, regions of high wall shear stresses at the distal neck could also be suppressed by almost 90%. The present results would be useful for further improvements in stent (or spring) technology.

Aneurysm↗

PubMed1999

Flavonoid glycosides from Thalictrum przewalskii.

A new flavonoid glycoside, 5,7-dihydroxy-4'-methoxyflavone-7-O-[6-O-(4-O-acetyl-alpha-L-rhamnosyl)-3-O-beta-D-glucosyl]-6-O-acetyl-beta-D-glucoside and three known flavonoid glycosides, 5,7-dihydroxy-4-methoxyflavone-7-0-[6-0-(4-0-acetyl-alpha-L-rhamnosyl)]-beta-D-glucoside, 3,5,7, 4'-tetrahydroxyflavonol-3-O-beta-D-glucoside and 5,7-dihydroxy-4'-methoxyflavone-7-O-(6-O-alphaL-rhamnosyl)-beta-D-glucoside were isolated from the whole plant of Thalictrum przewalskii. Their structures were determined on the basis of spectroscopic evidences.

Flavonoids↗

PubMed1999

Combined use of mini-laparoscope and conventional laparoscope in laparoscopic cholecystectomy: preservation of minimal invasiveness.

Mini-laparoscopic cholecystectomy using a 2-mm mini-laparoscope has been reported to be beneficial but technically difficult. This study attempted to evaluate the relative efficacy of a new method, which provides the benefits of both conventional and mini-laparoscopic cholecystectomy. From March 1997 to December 1997, 143 patients (49 men, 94 women, mean age 52.6 years, range 20-79), American Society of Anesthesiology (ASA) class I-II, underwent elective cholecystectomy by a combination of a 2-mm mini-laparoscope and 10-mm conventional laparoscope (combined lap-aroscopic cholecystectomy, C group) in National Taiwan University Hospital, Taipei, Taiwan. The entire procedure was done through four ports (one 11-mm port and three 2-mm ports). For comparison, records from 46 patients receiving mini-laparoscopic cholecystectomy (M group, 17 men, 29 women, mean age 49.0 years, range 26-76) and 139 patients receiving conventional laparoscopic cholecystectomy (L group, 47 men, 92 women, mean age 51.2 years, range 28-82) by the same operative team were included retrospectively. Mean operation time, time until first postoperative oral intake, dosage of analgesic, and postoperative hospital stay as well as possible complications were compared. No significant differences concerning the age, sex, and ASA classification were identified between all groups. The operative time of the C group (59.9 +/- 17.3 min, p = 0.420) but was significantly shorter than that of the M group (72.8 +/- 26.5 min, p < 0.001). No differences concerning the analgesic usage (0.5 +/- 0.8 unit vs. 0.4 +/- 0.7 unit, p = 0.372), postoperative oral intake (4.4 +/- 1.9 h vs. 3.3 +/- 2.3 h, p = 0.067), and postoperative hospital stay (1.7 +/- 0.7 days vs. 1.7 +/- 0.7 days, p = 0.941) were found between the C group and the M group. However, compared with the L group, analgesic usage (0.5 +/- 0.8 unit vs. 0.8 +/- 1.0 unit, p = 0.003) and time until first postoperative oral intake (4.4 +/- 1.9 h vs. 6.2 +/- 3.0 h, p < 0.001) were less, and the postoperative hospital stay (1.7 +/- 0.7 days vs. 2.0 +/- 0.9 days, p = 0.002) was significantly shorter in the C group. Combined use of the mini-laparoscope and the conventional laparoscope in cholecystectomy provides the benefits of both conventional laparoscopic and mini-laparoscopic cholecystectomy. It is easier to perform than cholecystectomy that uses the mini-laparoscope alone and results in a much smaller wound with less pain than conventional laparoscopic cholecystectomy. It is a feasible, safe procedure, and the minimal invasiveness of mini-laparoscopic cholecystectomy is preserved. It is an alternative way to deal with gallstone disease, especially for younger women, who tend to be more concerned about cosmetic outcome.

Adult↗

PubMed1999

Secretion of acute-phase proteins before and after hepatocellular carcinoma resection.

Hepatocyte growth factor (HGF), interleukin-6 (IL-6), and C-reactive protein (CRP) are acute-phase reactants that are usually present at high concentrations in the serum of patients with liver disease. However, the origin of these high serum concentrations is not completely understood, and whether hepatocellular carcinoma (HCC) tissue is a contributing factor is a controversial issue. The purpose of this study was to investigate the profiles of these three proteins in patients with HCC before and after tumor resection, and to study factors that might affect the serum concentrations of these proteins. A retrospective cohort study was performed in 34 consecutive patients who underwent HCC resection at the National Taiwan University Hospital. Blood samples were collected before surgery and on days 1, 3, 5, 7, and 14 postoperatively for serum concentration determinations of these three proteins. Twenty-three patients admitted for health examinations were enrolled as normal controls. Multiple regression analysis was conducted to evaluate the correlations between the pre- and postoperative cytokine concentrations and various clinical parameters. Compared with normal controls, the HCC patients had a significantly higher preoperative concentration of HGF (1,472 +/- 73 vs 948 +/- 54 ng/mL, p < 0.001) and IL-6 (44.1 +/- 6.9 vs 8.1 +/- 3.2 pg/mL, p = 0.012). These concentrations peaked on the first postoperative day and then declined to preoperative values on the fifth postoperative day. The CRP concentration was also higher in HCC patients (0.88 +/- 0.22 vs 0.21 +/- 0.06 mg/dL, p = 0.222), but the difference was not statistically significant. However, the CRP concentration did not return to the preoperative value within 2 weeks postoperatively. Preoperatively, HGF and CRP concentrations were positively affected by larger tumor size, and IL-6 concentration was negatively affected by hepatitis B surface antigen positivity and a higher indocyanine green (ICG) retention rate. In summary, the serum concentrations of HGF and IL-6 were significantly higher in HCC patients than in normal controls. The serum concentrations of HGF, IL-6, and CRP rose dramatically after HCC resection. The concentrations of these proteins were affected by different clinical parameters. We proved indirectly that high serum concentrations of HGF, IL-6, and CRP in patients with HCC do not result primarily from synthesis by the tumor cells. Whether the preoperative concentrations of these proteins correlate with the clinical outcome needs further follow-up.

Acute-Phase Proteins↗

PubMed1999

Complete pathological remission is possible with systemic combination chemotherapy for inoperable hepatocellular carcinoma.

The purpose of this Phase II study was to determine the response rate, the toxicity, and the effect on survival of the combination of cisplatin, doxorubicin, 5-fluorouracil, and alpha-IFN (PIAF) in advanced unresectable hepatocellular carcinoma. Fifty patients with either unresectable or metastatic disease were treated with PIAF: cisplatin (20 mg/m2 i.v., days 1-4), doxorubicin (40 mg/m2 i.v., day 1), 5-fluorouracil (400 mg/m2 i.v., days 1-4), and alpha-IFN (5 MU/m2 s.c., days 1-4). Treatment was repeated every 3 weeks to a maximum of six cycles. All patients were evaluable for response, toxicity, and survival. As assessed by conventional imaging criteria, there were no complete responses, but 13 patients (26%) had a partial response. Among the 36 patients who had an initially high alpha-fetoprotein level (>500 ng/ml), 15 (42%) had a >50% fall after therapy. Nine patients underwent surgical resection after achieving partial response and, in 4 of these patients, histological examination of the resected specimens revealed no viable tumor cells. All these nine patients are alive, and eight patients remain in complete remission at between 7.6 and 25.8 months at the time of analysis. The overall median survival was 8.9 months. Toxicity was mainly myelosuppression and mucositis. There were two treatment-related deaths due to neutropenic sepsis. PIAF is active in hepatocellular carcinoma despite considerable hematological toxicity. Complete pathological remission is possible with this systemic combination. Apparently, persistent radiological lesions may still represent complete pathological resolution of active disease.

Adolescent↗

PubMed1998

High-dose therapy with peripheral blood stem cell (PBSC) support using an innovative mobilization regimen in patients with high-risk primary or chemoresponsive metastatic breast cancers.

High-dose therapy followed by peripheral blood stem cell (PBSC) support was performed in 29 patients with primary high-risk (Group I) or chemoresponsive metastatic (Group II) breast cancer patients. Group I patients had received PBSC mobilization within 4 weeks of modified radical mastectomy. Group II patients had to achieve minimal residual disease (MRD) by induction chemotherapy before being considered eligible for PBSC mobilization and high-dose therapy. An innovative FE120C regimen (5-FU 600 mg/m2, i.v., day 1; epirubicin 120 mg/m2, i.v., day 1; cyclophosphamide 600 mg/m2, i.v., day 1) plus G-CSF (300 microg/day, subcutaneous injection for 9 days, from day 4 post-FE120C) was used to mobilize PBSCs. After high-dose CTCb (cyclophosphamide 6,000 mg/m2, thiothepa 500 mg/m2, carboplatin 800 mg/m2, in 4 days), patients received PBSC infusion and daily C-CSF 300 microg subcutaneous injection. There were 19 and 16 patients enrolled into Group I and Group II, respectively. Ten of the Group II patients had achieved minimal residual disease (MRD) after induction chemotherapy. The median numbers of mobilized total CD34 + cells for Group I and Group II patients were 27.3 (9.2 to 114.1) x 10(6)/kg and 17.1 (5.9 to 69.1) x 10(6)/kg respectively. The median time to neutrophil recovery (ANC > or = 500/microL) was 8 and 9 days in Group I and II, respectively. The median time to platelet recovery (> or = 50,000/microL) was 10 and 15 days in Group I and II, respectively. No major treatment-related toxicities were noted. In Group I, 13 out of 19 patients (68.4%; 43-87%, 95% C.I.) remained recurrence-free with a median follow-up of 31 months (6 + to 55 + months). In Group II, 3 out of 10 patients (30%; 7-65%, 95% C.I.) remained progression-free at 33 +, 35 +, 39 + months from induction therapy. We suggest that the FE120C plus G-CSF is an effective and innovative regimen for PBSC mobilization in breast cancer patients, and high-dose CTCb therapy with PBSC support is a safe and well-tolerated treatment modality.

Adult↗

PubMed1998

Water-soluble contrast study predicts the need for early surgery in adhesive small bowel obstruction.

BACKGROUND: The optimal period of conservative treatment for adhesive small bowel obstruction remains controversial. This study sought to determine whether a 24-h abdominal radiograph after oral Urografin is a reliable indicator for operation in patients with adhesive small bowel obstruction. METHODS: One hundred and sixty-one patients who suffered from adhesive intestinal obstruction without clinical evidence of strangulation or gangrene underwent a Urografin study. Some 40 ml Urografin mixed with 40 ml distilled water was administered either orally or via a nasogastric tube to each patient. Serial plain abdominal radiographs were taken 4, 8, 16 and 24 h later. If an earlier plain radiograph showed that contrast medium had reached the ascending colon, subsequent radiographs were not taken. RESULTS: Contrast medium reached the colon within 24 h in 112 patients (70 per cent). These patients were all treated successfully with non-operative methods. Contrast medium was not observed in the colon within the first 24 h in 49 patients (30 per cent). Operation was performed in 47 of these patients and non-operative treatment was given in two. The sensitivity, specificity, accuracy, positive predictive value and negative predictive value of Urografin reaching the colon within 24 h as an indicator for non-operative treatment were 98, 100, 99, 100 and 96 per cent respectively. CONCLUSION: All patients with evidence of Urografin reaching the colon within 24 h were treated successfully with non-operative methods. The results of this prospective study suggest that patients with adhesive intestinal obstruction in whom contrast medium fails to reach the colon within 24 h should receive prompt surgical intervention.

Adult↗

PubMed1998

Laparoscopic management of a gastric perforation after snare removal of a gastric leiomyoma.

A 67-year-old man with a history of myocardial infarction, who had been suffering intermittent epigastric pain and tarry stool for nine months, was referred to our hospital with a suspected gastric tumor. The panendoscopy showed a round, hard submucosal tumor at the greater curvature of the upper gastric body, near the fundus. An ulcer scar was observed on the surface of the tumor. Polypectomy using snare cauterization was carried out. However, severe abdominal pain and abdominal distension developed. A chest radiograph revealed bilateral subphrenic free air. Due to the high risk in this patient, laparoscopic repair of the gastric perforation was carried out using an Endo-GIA instrument. The postoperative course was uneventful. Feeding started on the third postoperative day, and the patient was discharged on the eighth day. A follow-up panendoscopy two months later showed a well-healed scar.

Aged↗

PubMed1998

Minilaparoscopic splenectomy: a new minimally invasive approach.

This report introduces our new technique in laparoscopic splenectomy. A 2-mm minilaparoscope and a conventional 10-mm laparoscope were used alternatively during the procedure, with a result of nearly no visible scar after the operation. Two young females diagnosed with idiopathic thrombocytopenic purpura, refractory to medical treatment, underwent laparoscopic splenectomy in our hospital. The whole procedure was finished through one 12-mm port (supraumbilical) and three 2-mm ports (subxiphoid, left midclavicular, and left midaxillary). The short gastric vessels and splenic vessels were clipped and divided by Endo-GIA II (U.S. Surgical Corp., Norwalk, CT) that was applied through the 12-mm port. The spleen was placed in a bag and was fractured to be removed piece by piece. A drain tube was not necessary after meticulous hemostasis. Two weeks after the operation, only three tiny wounds, resembling mosquito bites, were present at the left subcostal region. In conclusion, minilaparoscopic splenectomy is feasible and safe for patients with idiopathic thrombocytopenic purpura, and may ultimately be an alternative choice for patients desiring superior cosmesis.

Adult↗

PubMed1998

A comparison of three fluid-vasopressor regimens used to prevent hypotension during subarachnoid anaesthesia in the elderly.

We aimed to compare the efficacy of fluid preloading with two recently recommended fluid-vasopressor regimens for maintaining blood pressure during subarachnoid anaesthesia in the elderly. Sixty elderly patients requiring surgery for traumatic hip fractures received subarachnoid anaesthesia using 0.05 ml/kg of 0.5% heavy bupivacaine. Hypotension, i.e. systolic arterial pressure < 75% of baseline, was prevented or treated by: A--normal saline 16 ml/kg plus intravenous ephedrine boluses (0.1 mg/kg); B--normal saline 8 ml/kg plus intramuscular depot ephedrine (0.5 mg/kg); or C--Haemaccel 8 ml/kg plus metaraminol infusion. Systolic arterial pressure and heart rate were recorded using custom-written computer software (Monitor, version 1.0). Systolic arterial pressure decreased in all groups after five minutes (P < 0.001). Decreases were greatest in group A (P < 0.05). Heart rate increased by 7% group A and decreased by 9% in group C (P < 0.05). During the first hour, hypotension was present for 47%, 25% and 20% of the time in groups A, B and C respectively and overcorrection of systolic arterial pressure occurred in 19% of the time in group C. We conclude that treatment A was inadequate in preventing hypotension. Treatments B and C were more effective but were associated with an increased heart rate and overcorrection of systolic arterial pressure respectively.

Aged↗

PubMed1998

Percutaneous biopsy of small hepatic lesions using an 18 gauge automated needle.

This study evaluates the efficacy of ultrasound guided percutaneous biopsy using an 18 gauge automated side-cutting needle in the diagnosis of small (< or = 3 cm) focal hepatic lesions. 137 consecutive percutaneous biopsies of 131 different small (< or = 3 cm) focal hepatic lesions were included. 11 biopsies were performed on lesions of < or = 1 cm in diameter, 56 were on lesions 1.1-2 cm in size and 70 on lesions 2.1-3 cm in size (average 2.3 +/- 0.7 cm; median 2.3 cm; range 0.7-3 cm). The biopsy specimen was sufficient for diagnosis in 135 cases (98.5%). The sensitivity for diagnosing malignancy was 96.4%; specificity was 100%, positive and negative predictive values were 100% and 94.6%, respectively; accuracy was 97.8%. There was no statistically significant difference in the diagnostic efficacy for lesions of different pathology and size. No significant post-biopsy complication occurred. It is concluded that the 18 gauge Temno needle is safe and effective in diagnosing small hepatic lesions.

Adolescent↗