Elderly kidney transplant recipients have favorable outcomes but increased infection-related mortality

임정훈,Lee Ga Young,Jeon Yena,Jung Hee-Yeon,Choi Ji Young,CHO, JANG-HEE,Park Sun Hee,김용림,Kim Hyung-Kee,Huh Seung,유은상,Won Dong Il,Kim Chan-Duck 대한신장학회 2022 Kidney Research and Clinical Practice Vol.41 No.3

Background: The number of elderly patients with end-stage kidney disease has been increasing, but the outcomes of kidney transplants (KT) remain poorly understood in elderly patients. Therefore, we evaluated the clinical outcomes of elderly KT recipients and analyzed the impact of elderly donors. Methods: This retrospective cohort study included patients who underwent KT between 2000 and 2019. KT recipients were divided into four groups according to a combination of recipient and donor age (≥60 or <60 years); elderly recipients: old-to-old (n = 46) and young-to-old (n = 83); young recipients: old-to-young (n = 98) and young-to-young (n = 796). We compared the risks of mortality, graft failure, and acute rejection between groups using Cox regression analysis. Results: The incidence of delayed graft function, graft failure, and acute rejection was not different among groups. Annual mean tacrolimus trough level was not lower in elderly recipients than young recipients during 10-year follow-up. Mortality was significantly higher in elderly recipients (p = 0.001), particularly infection-related mortality (p < 0.001). In multivariable Cox regression analysis, old-toold and young-to-old groups had increased risk of mortality (adjusted hazard ratio [aHR], 2.89; 95% confidence interval [CI], 1.14– 7.32; p = 0.03; aHR, 3.06; 95% CI, 1.51–6.20; p = 0.002). However, graft failure and acute rejection risks were not increased in elderly recipients. Conclusion: In elderly recipients, graft survival and acute rejection-free survival were not inferior to those of young recipients. However, mortality, especially risk of infection-related death, was increased in elderly recipients. Thus, low immunosuppression intensity might help decrease mortality in elderly recipients.

비만증 환자에서 한약제에 의한 체중 감소효과

Oh, Seung-Joon,Jeong, In-Kyung,Kim, Young-Seol,Choi, Young-Kil,Paeng, Jeong-Ryung,Bae, Jung-Hwan,Shin, Hyun-Dae 경희대학교 동서의학연구소 1999 INTERNATIONAL SYMPOSIUM ON EAST-WEST MEDICINE Vol.1999 No.1

Seung-Joon Oh, In-Kyung Jeong, Young-Seol Kim, Young-Kil Choi, Jeong-Ryung Paeng¹, Jung-Hwan Bae and Hyun-Dae Shin²Department of internal Medicine, College Medicine, Endocrine Research Institute¹. Department of Rehabilitation, College of Oriental Medicine², Seoul, korea. Bady Fat Reduction Effects of Red Ginseng Compound Preparation on the Patients with Obesity. Proceedings of International Symposium on East-West Medicine, Seoul. 244-254, 1999.-Obesity can be defined as a metabolic disease due to an increased state of fat tissues caused by an imbalance of calorie intake and use. Recently, in Korea by improvement and westernization of food intake, along with decrease in exercise activities, the prevalence of obesity has increased greatly. Our objectives were to study stability and effects of decrease in body fat by administering red ginseng compound preparation (known to have body fat decreasing effects in laboratory animals) to obesity patients on low calorie diets. Changes in weight and body fat were measured while carrying out calorie-restricted diets on patients for 4 weeks, then administering red ginseng compound preparation for another 4 weeks. The patients were 20 people whose BMI were 25kg/㎡ or over and whose percent body fat was also 30% or over when tested by bioelectrical conductivity. 1. Changes in weight were from 70.04kg(base line) to 67.43kg(after taking red ginseng compound preparation). 2. In similar sense, BMI decreased from 27.12kg/㎡(base line) to 26.56kg/㎡(after dieting), and further to 26.01kg/㎡ (after taking red ginseng compound preparation). The BMI seemed to decrease significantly compared to the baseline after the use of red ginseng compound. 3. Waist hip ratio was changed from 0.8858(base line) to 0.8728, but it was statistically insignificant. 4. The percent body fat was 35,16%(base line), 33.87%(after dieting), and 31.68%(after taking red ginseng compound preparation). 5. Complete blood cell count and blood chemisrty remained unaffected by the administration. 6. In concern to endocrinologic studies, T3 decreased from 118.7 to 98.2ng/dL, and T4 increased from 8.8 to 9.2㎕/ dL. Epinephrine showed a tendency to decreased from 0.27 to 0.25 ng/mL, and norepinephrine increased from 0.39 to 0.44ng/mL. 7. Leptin was not changed. 8. Some patients complained adverse effects; constipation(5 patients, may be due to diet therapy), fatigue (2 patients), pruritus(2 patients), flushing(s patients), dizziness(3 patients) and epigastric discomfort(2 patients). However their symptoms were mild, so medication did not stopped. In conclusion, loss of weight without significant side effects was observed during low calorie diet and red ginseng compound preparation administration. This is thought to be in relation to sympathetic nerve system rather than adrenal gland. Also, further long0term studies should be required, since the observed results were based on short-term changes in weight.

정신분열병에 대한 리스페리돈의 효과 및 안정성

이민수,김용구,김영훈,연병길,오병훈,윤도준,윤진상,이철,정희연,강병조,김광수,김동언,김명정,김상훈,김희철,나철,노승호,민경준,박기창,박두병,백기청,백인호,손봉기,손진욱,양병환,양창국,우행원,이정호,이종범,이홍식,임기영,전태연,정영조,정영철,정인과,정인원,지익성,채정호,한상익,한선호,한진희,서광윤 大韓神經精神醫學會 1998 신경정신의학 Vol.37 No.1

연구목적 : 본 시험의 목적은 임상시험 시작전에 연구자들을 대상으로 PANSS Workshop을 통하여 PANSS, ESRS에 대한 국내에서의 표준화 작업을 구축하고 새로운 정신병 치료제인 리스페리돈의 효과와 안정성을 재확인하여 리스페리돈 사용에 대한 적정화를 이루는데 있다. 연구방법 : 1996년 4월부터 1996년 9월까지 국내 39개 대학병원 정신과에 입원중인 혹은 증상이 악화되어 입원하는 정신분열병 환자 377명을 대상으로 다시설 개방 연구를 시행하였다. 1주일간의 약물 배설기간을 가진후, 리스페리돈을 8주간 투여하였고, 기준점, 1주, 2주, 4주, 그리고 8주후에 평가되었다. 용량은 제1일에는 리스페리돈 1mg씩 1일 2회, 제2일에는 2mg씩 1일 2회, 제3∼7일에는 3mg씩 1일 2회 투여하였다. 이후 환자의 임상상태에 따라 임의로 증량할 수 있으며, 최대 일일 16mg을 초과하지 않도록 하였다. 추체외로 증상을 조절하기 위한 투약을 허용하였다. 임상증상 및 부작용의 평가는 PANSS(Positive and Negative Syndrome Scale), CGI(Clinical Global Impression) 그리고 ESRS(Extrapyramidal Symptom Rating Scale)을 사용하였다. 연구결과 : 377명중 343명(91%)이 8주간의 연구를 완결하였다. 치료 종결시점인 8주후 PANSS 총점수가 20% 이상 호전된 경우를 약물 반응군으로 정의할때, 약물반응군은 81.3%였다. 리스페리돈에 반응하는 예측인자로는 발병연령, 이전의 입원 횟수, 유병기간이 관련 있었다. 리스페리돈은 1주후부터 PANSS양성, 음성, 및 일반정신병리 점수상에 유의한 호전을 보여 효과가 빨랐다. CGI의 경우도 기준점에 비해 1주후부터 유의한 감소를 나타내었다. ESRS의 경우, 파킨슨 평가점수는 기준점과 비교해 투여 1주, 2주, 4주후 유의하게 증가되었다가 8주후 기준점과 차이가 없었다. Dystonia 평가점수는 1주후만 유의한 증가를 보였으며, dyskinesia 평가점수는 유의한 차이가 없었다. 혈압, 맥박수의 생명징후 및 일반 혈액학 검사, 생화학적 검사, 심전도 검사에서 유의한 변화는 없었다. 결 론 : 이상의 다시설 개방 임상 연구를 통해 리스페리돈은 정신분열병 환자에서 양성증상뿐만 아니라 음성증상 및 전반적인 증상에도 효과적인 것으로 사료된다. 보다 명확한 평가를 위해서는 다른 항정신병약물과의 이중맹검 연구가 필요할 것으로 생각되며, 또한 장기적 치료에 대한 평가도 함께 이루어져야 하겠다. Objective : The purpose of this study was to investigate the efficacy and safety of risperidone in the treatment of Korean schizophrenic patients. Method : This multicenter open study included 377 schizophrenic patients drawn from 39 university hospitals. After a wash-out period of 1 week, the schizophrenic patients were treated with risperidone for 8 weeks and evaluated at 5 points ; at baseline, and 1, 2, 4 and 8 weeks of treatment. The dose was increased from 2mg/day(1mg twice daily) to 6mg/day(3mg twice daily) during the first week and adjusted to a maximum of 16mg/day over the next 7 weeks according to the patient's clinical response. Medication to control extrapyramidal symptoms was permitted. The psychiatric and neurological status of the patients was assessed by PANSS, CGI, and ESRS scales. Results : 343(91%) of 377 patients completed the 8-week trial period. Clinical improvement, as defined by a 20% or more reduction in total PANSS score at end point, was shown by 81.3% of patients. The predictors of response to risperidone were associated older age, shorter duration of illness, fewer previous hospitalization. Risperidone had rapid onset of action ; a significant decrease of the total PANSS and three PANSS factor(positive, negative, general), and CGI was already noticed at the end of first week. For the ESRS, parkinsonism rating scores were significantly increased until week 4 comparing with baseline. Dystonia rating scores were significantly increased until week 1, and dyskinesia rating scores were not significantly changed during the study. Laboratory parameters including vital sign, EKG, hematological, and biochemical values showed no significant changes during the trial. Conclusions : This study suggests that risperidone is generally safe and effective against both the positive and negative symptoms in our group of patients.

20년전과 비교한 한국청년의 미소 변화에 관한 연구

범승균,정지혜,김태영,이경은,동진근 大韓齒科補綴學會 2012 대한치과보철학회지 Vol.50 No.3

Purpose: Teeth are generally exposed when people smiling. Moreover, the exposed teeth and soft tissue when smiling becomes an important guideline for esthetically prosthetic restoration. This research is to compare and find out differences of Korean young men's smile living in presence and twenty years ago. Materials and methods: Subjects, 100 young men (50 male and 50 female), were required about several aspects; normally developed physical condition, no psychological or genetic disorders, a fine face with no loss of teeth, no experience in orthodontic or prosthetic treatment, relatively normal occlusion, aged between 20 - 29. The photos of the subject at rest position and front face when fully smiled were taken three times. 100 photos (50 male and 50 female) were chosen at random from the 240 university students' smile photos taken by Yoon and his colleagues in 1991. By Hulsey's method of measuring smile, several factors; the change of upper lip curvature, the change of the relation between the upper lip and teeth, parallelism between Mx. incisor and lower lip, contact relation between Mx. incisor and lower lip and teeth displayed in a smile, were measured and analyzed. Meanwhile, ten dentists assessed aesthetic evaluation about men and women's smile for twice and recorded and compared smile score. The -test (P<.05) was used to compare the measured value. The difference of smile score was analyzed by t-test (P<.05). Results: The smile score calculated in 2011 (60.22) was higher than that of 1991 (52.80). Among five measurement categories, the noticeable difference was distinguished from two factors; the change of upper lip curvature and contact relation between Mx. incisor and lower lip. Conclusion: The Korean young men's smile has been considerably improved for twenty years. And it is found that the change of upper lip curvature plays an important role, that is, the smile formed with an ascended labial commissure has been increased significantly. 연구 목적: 일반적으로 치아는 미소 지을 때 가장 많이 노출되며, 미소 시에 나타나는 치아와 연조직과의 관계 등은 심미적인 보철 수복에 있어서 중요한 지침이 된다. 본 연구는 20년 전 한국 청년들의 미소와 현재 한국 청년들의 미소를 비교하여 그 차이를 알아보고자 하였다. 연구 재료 및 방법: 신체적인 발육 상태가 정상적이고 전신적 또는 유전적 질환이 없으며, 안모가 양호하고 치아의 결손이 없으며 교정 및 보철치료를 받은 경험이 없고, 교합상태가 비교적 정상적인 20 - 29세 사이의 청년 100명(남자 50명, 여자 50명)을 대상으로, Cephalometer에 사용되는 두부 고정 장치를 사용하여 피검자의 F-H plane이 지면에 평행하도록 한 후, 35 mm 카메라(400D. Cannon, Japan), 120 mm 렌즈 그리고 삼각대를 사용하여 피검자의 midsagittal plane에 카메라 렌즈의 중심을 맞추고 상악 중절치 절단과 렌즈와의 거리를 930 mm로 하여 안정위 및 full smile 시의 안모 정면 사진을 3회씩 촬영하였다. 1991년 윤 등이 촬영한 대학생 240명 중 무작위로 선택한 100명(남자 50명, 여 자 50명)의 미소사진과 함께 개인용 컴퓨터 및 V-ceph 6.0 프로그램을 이용하고 Hulsey의 미소 계측 방법을 참고로 하여, 상순의 형태, 상순과 치아와의 관계, 하순과 상악 전치 절단연과의 평행 관계, 하순과 상악 전치 절단연과의 접촉 관계, 미소시 나타나는 치아 등을 계측하고 분석하였다. 한편 치과의사 10인이 남,녀 각 2회씩 미소에 대한 미적 평가를 시행하여 미소평점을 기록하고 비교하였다. 결과: 지난 20년간 한국 청년의 미소가 크게 향상되었으며 이러한 변화는 주로 상순의 형태가 영향을 준 것을 알 수 있었다. 즉 입꼬리가 위로 올라가는 형태의 미소가 괄목할 만한 증가를 보인 반면 입 꼬리가 아래로 처지는 형태의 미소는 현저한 감소를 보였다. 결론: 지난 20년간 한국 청년의 미소가 크게 향상되었는데 이러한 변화는 주로 상순의 형태가 영향을 준 것으로 나타났다.

미치광이풀 모상근 배양에서 Tropane Alkaloid 생산성 증진을 위한 최적 생물학적 엘리시터 선발

정희영,강승미,강영민,김용덕,양재경,정영관,최명석 Plant molecular biology and biotechnology research 2003 Plant molecular biology and biotechnology research Vol.2003 No.-

Scopolamine and hyoscyamine which belong to tropane alkaloids are the pharmaceutically valuable anticholinergic drugs. In order to increase the productivities, the effects of elicitation were investigated during hairy root cultures of Scopolia parviflora. Biotic elicitors originated from 3 fungi and 1 yeast were prepared as homogenate and supernatant and added to 3-week-old cultures. Both of homogenate and supernatant of Candida albicans elicitors increased the scopolamine production. The production of hyoscyamine was enhanced by homogenate of Fusarium solani and supematant of C. albicans. Most of the other fungal elicitors were also improved on the tropane alkaloid production compared to non-treatment. Among the elicitors tested, C. albicans was proved the optimal biotic elicitor on tropane alkaloids production. These results will be served mass production of tropane alkaloids by large-scale production.

Rat의 복강내에 투여한 5-fluorouracil-polyglycolic acid 제형이 장기에 미치는 영향에 관한 연구

강대영,송규상,최정목,노승무,정경수,오정연,김진향,양준묵,최선웅,이진호,조준식,민병무,김용백,김창식,박근성,김승영,김학용,인현빈 충남대학교 의과대학 지역사회의학연구소 1998 충남의대잡지 Vol.25 No.1

For more effective intraperitoneal chemotherapy, the authers made 5-fluorouracil-polyglycolic acid composite disks(FU-PGA disks) with 5-fluorouracil and polyglycolic acid, a biodegradable polymer. We inserted the FU-PGA disk into the peritoneal cavites of Sprague-Dawley male rats, the control and three experimental groups; one FU-PGA disk insert group(300mg/kg), two FU-PGA disk insert group(600mg/kg), and three FU-PGA disk insert group(900mg/kg). The control group received a similar number of PGA disk inserts. A pharmacokinetic study was performed to measure the 5-fluorouracil concentration in the peritoneal fluid, blood, and tissues(liver, kidney and heart) at 24 hours, 72hours and 168 hours after insertion of the FU-PGA disk. Light and electron microscopic studies were done. The results were as follows: 1) The number of white blood cells and platelets decreased after FU-PGA insertion. The degree was proportional to the duration and amounts inserted. The change in the number of red blood cells varied slightly. 2) Light microscopically, slight changes were noted at 168 hours in the 3 disk insert group (900mg/kg). Mild fatty change and hepatocyte degeneration around the central veins of the liver were noted, with vacuolar degeneration in the proximal convoluted tubules of the kidney. 3) Electron microscopically,the liver showed focal increases of lipid droplets in the hepatocytes, and irregular nuclear membrane with focal nucleolar segregation of the fibrillar and granular elements. Also the double membranous structure of the hepatocytes and Kupffer cells was widened with bleb formation. The kidney showed wide separation of the nuclear double membrane in the proximal convoluted tubular cells and mesangial cells, with vacuolation and myelin figure formation in the mitochondria of the proximal convoluted tubular cells, at 72 hours and 168 hours in the 2 to 3 FU-PGA insert groups. The heart showed focal loss of cristae,vacuolation and myelin figure formation in the mitochondria of the 2 to 3 FU-PGA insert groups. In conclusion, despite the large amont of FU-PGA inserted, the histopathological changes in the liver, kidney and heart were slight, and consonant with the very low amount of 5-fluorouracil concentrations detected in the liver, kidney and heart. The above results suggest that the FU-PGA composite can serve as a new device for releasing drugs in a controlled manner and easily targeted to intraperitoneal organs. This device can improve the efficacy of intraperitoneal chemotherapy for gastric cancer.

최근 9년간 신경정신과에 입원한 환자에 대한 임상적 고찰(1972∼1980년)

이정호,안일남,오석환,정영조,최영민,원장섭,김영훈,하혜경,이승탁,이영주 인제대학교 1983 仁濟醫學 Vol.4 No.2

정신질환 환자들에 대한 정확한 생태를 파악함은 정신 건강과 치료 대책을 세우는데 중요하다. 이에 본 저자들은 1972년부터 1980떤 사이에 인제의대 부속 서울백병원 신경정신과에 입원하여 치료 받았던 환자들에 대한 제반 요인들을 분석 검토하였다. Clinical charactristics of neuropsychiatric inpatients were evaluated and discussed with special referrence to their diagnostic distribution. All discharged cases from neuropsychatric ward of Seoul Paik Hospital during nine years from 1972 to 1980 were 2863. Among them 813 cases were discarded from this study because their clinical charts were vague in description of failed to find out. The materials of this study were extracted from 2050 discharged cases. Total number of cases of inpatients were gradually increasing by each year from 1972 to 1980. Psychoneurosis was diagnosed in 45.2%, schizophrenia in 26.9%, organic brain syndrome in 8.9%, major affective disorder in 5.5%, personality disorder in 4.8%, other psychiatric disorder in 1.5%, psychophysiologic disorder in 1.0%, mental retardation in 0.5%, paranoid state in 0.5%, and other psychosis in 0.3%. The gruop of patients, ranging in age from 21 to 40 was the highest (75.2%) in this study. Male patients were 43.9% and female patients were 56.1%. Schizophrenia leas diagnosed in 32.9%, depressive neurosis in II.3%, anxiety neurosis in 9.3%, and personality disorder in 8.1% in male patients. Hysterical neurosis was diagnosed in 25.5%, depressive neurosis in 22.2%, schizophrenia in 22.2%, and anxiety neurosis in 7.0% in female patients. The authors evaluated the route of admission of patients. Sixty-eight point three percent of total studied cases were admitted through outpatient department, 20.9% of cases were admitted through emergeney room, and 8.2% of cases were transfered from other department or hospital. Among patients who were admitted to psychiatric wards through emergency room and transferred from other department or hospital, psychoneurosis was the hightest diagnostic group in rate. Most of patients who were transferred from other department or hospital were from Internal Medical Department. There were no relationship between seasonality of admission and diagnostic group in this study. readmission rate of total studied patients in neuropsychiatric department of Seoul Paik Hospital was 30%. The readmission rate of personality disorder, mental retardation, schizophrenia, and major affective disorder were relatively high. The cases who were discharged against medical advice were 441. Among them misunderstanding about psychiatric treatment was predominent. Twenty seven percent of patients had physical illness at or during admission. The patients who were diagnosd as psychophysiological disorder had physical illness in 42.8%, 35.4% in personality disorder, 33.9% in major affective disorder, and 24.3% in schizophrenia. About nine percent of total studied cases had the history of attempted suicide. Major affective disorder, Personality disorder, Deressive neurosis, and Other Psychosis showed high incidence of history of attempted suicide prior to admission.

Rat의 복강에 삽입한 Filorouracil-Polyglycolic acid제형의 Fluorouracil용출에 관한 연구

노승무,정경수,오정연,김진향,양준묵,강대영,송규상,최정목,최선웅,이진호,조준식,민병무,김용백,김창식,박근성,김승영,김학용,인현빈 충남대학교 의과대학 지역사회의학연구소 1998 충남의대잡지 Vol.25 No.1

A common form of relapse in adenocarcinoma of the stomach is intraperitioneal dissemination, in fact, among gastric adenocarcinoma patients who have undergone surgery intended to cure, approximately 50% of the patients develope initial recurrence in the peritoneal cavity regardless of the anatomic site of the primary tumor within the stomach. The efficacy of systemic postoperative chemotherapy to prevent peritoneal recurrence of gastrric adenocarcinoma is not satisfactory. There is still a great need for improved therapeutic strategies on the disseminated microscopic disease and small miliary nodules remaining on the peritoneal surface or lymphatics after operation. The authers have made fluorouracil-polyglycolic acid composite disks(Fu-PGA disks) with fluorouracil and biodegradable polymer: polyglycolic acid for more effective intraperitoneal chemotherapy. We inserted the Fu-PGA disk(s) in the peritoneal cavity of rat and pharmacokinetic study was performed to measure fluorouracil concentration in the peritoneal fluid, plasma, liver, kidney and heart tissue at 24 hour, 72 hour and 168 hour after insertion of Fu-PGA disk(s). Myelosuppressive action of this composite also was determined following its administration. The data of this study suggested that Fu-PGA composite will be a new device releasing drugs in a controlled manner and having targetability to peritoneum, and this device will be improving the efficacy of intraperitoneal chemotherapy for gastric adenocarcinoma.

급성 골수성 백혈병 환자에서 발생한 침습성 아스페르길루스중에 대한 수술적치료 1 예

배영환;어원식;어상민;김승만 김태영;박수영;서영경;정은주;안효정 인제대학교 2011 仁濟醫學 Vol.32 No.-

Invasive pulmonary aspergillosis is known to have a poor prognosis and major cause of morbidity and motality in patients with hematologic disease. Without adequate therapy, invasive pulmonary aspergillosis will almost always progress to fatal pneumonia. Early administration of antifungal agents in patient with invasive pulmonary aspergillosis is most important. And surgical resection of aspergillous-infected tissue may be useful in patients with lesions that are contiguous with great vessel and lesions causing hemoptysis. We reported a rare case of surgical resection as curative treatment for invasive pulmonary aspergillosis patient in 58-year-old man who had the history of acute myeloid leukemia.

High-frequency micromechanical resonators from aluminium–carbon nanotube nanolaminates

Bak, Jung Hoon,Kim, Young Duck,Hong, Seung Sae,Lee, Byung Yang,Lee, Seung Ran,Jang, Jae Hyuck,Kim, Miyoung,Char, Kookrin,Hong, Seunghun,Park, Yun Daniel Nature Publishing Group 2008 NATURE MATERIALS Vol.7 No.6

At micro- and nanoscales, materials with high Young’s moduli and low densities are of great interest for high-frequency micromechanical resonator devices. Incorporating carbon nanotubes (CNTs), with their unmatched properties, has added functionality to many man-made composites. We report on the fabrication of ≤100-nm-thick laminates by sputter-deposition of aluminium onto a two-dimensional single-walled CNT network. These nanolaminates—composed of Al, its native oxide Al<SUB>2</SUB>O<SUB>3</SUB> and CNTs—are fashioned, in a scalable manner, into suspended doubly clamped micromechanical beams. Dynamic flexural measurements show marked increases in resonant frequencies for nanolaminates with Al–CNT laminae. Such increases, further supported by quasi-static flexural measurements, are partly attributable to enhancements in elastic properties arising from the addition of CNTs. As a consequence, these nanolaminate micromechanical resonators show significant suppression of mechanical nonlinearity and enhanced strength, both of which are advantageous for practical applications and analogous to biological nanocomposites, similarly composed of high-aspect-ratio, mechanically superior mineral platelets in a soft protein matrix.