• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.1
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• pp.41-46
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• 1994

This study was undertaken to clarify the effect of killing methods on physical and rheological changes of plaice, Paralichthys olivaceus muscle at early period after death. Plaices killed by the four different methods(1. spiking at the brain instantly. 2. drowning in air. 3. dipping in 1,000ppm ethylaminobenzoate dissolved sea water as an anesthetic. 4. electrifying in sea water.) were stored at $5^{\circ}C$, and the rigor-index and breaking strength through storage were monitored. The longest onset time of rigor-mortis and full rigor was in the samples killed by dipping in sea water with dissolved anesthetic among all samples, where rigor-mortis began at 20hrs after killing and maximum tension was attained after 56hrs. However, in the cases of plaice electrified in sea water or drowned in air, the onset of rigor-mortis began just after killing and maximum tensions were attained after 9hrs and 13hrs, respectively. The level of breaking strength in the muscle of fish killed by spiking the brain instantly was $950.30{\pm}50.23g$, immediately after killing. The value and time reached around the maximum breaking strength for each of the samples were $1,230.60{\pm}30.32g$ and Ohr (immediately after killing) for samples killed by electrifying in sea water, $1,235.83{\pm}35.37g$ and 2.5hrs for drowning samples, $1,186.29{\pm}55.90g$ and 10hrs for spiking samples, and $1,189.67{\pm}50.32g$ and 15hrs for samples dipped in anesthetic, respectively. From the results above, it could be concluded that electrification in sea water is the most effective method in accelerating rigor-mortis and shortening times of reaching the maximum breaking strength of fresh plaice flesh of all the killing methods at early periods after death, whereas dipping in sea water treated with anesthetic was the most effective way in delaying those changes.

• Journal of Chest Surgery
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• v.42 no.3
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• pp.292-298
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• 2009

Background: Surgery for mitral valve disease in children carries both technical and clinical difficulties that are due to both the wide spectrum of morphologic abnormalities and the high incidence of associated cardiac anomalies. The purpose of this study is to assess the outcome of mitral valve surgery for treating congenital mitral regurgitation in children. Material and Method: From 1997 to 2007, 22 children (mean age: 5.4 years) who had congenital mitral regurgitation underwent mitral valve repair. The median age of the patients was 5.4 years old and four patients (18%) were under 12 months of age. 15 patients (68%) had cardiac anomalies. There were 13 cases of ventricular septal defect, 1 case of atrial septal defect and 1 case of supravalvar aortic stenosis. The grade of the preoperative mitral valve regurgitation was II in 4 patients, III in 15 patients and IV in 3. The regurgitation was due to leaflet prolapse in 12 patients, annular dilatation in 4 patients and restrictive leaflet motion in 5 patients. The preoperative MV Z-value and the regurgitation grade were compared with those obtained at follow-up. Result: MV repair was possible in all the patients. 19 patients required reduction annuloplasty and 18 patients required valvuloplasty that included shortening of the chordae, papillary muscle splitting, artificial chordae insertion and cleft closure. There were no early or late deaths. The mitral valve regurgitation after surgery was improved in all patients (absent=10, grade I=5, II=5, III=2). MV repair resulted in reduction of the mitral valve Z-value ($2.2{\pm}2.1$ vs. $0.7{\pm}2.3$, respectively, p<0.01). During the mid-term follow-up period of 3.68 years, reoperation was done in three patients (one with repair and two with replacement) and three patients showed mild progression of their mitral reguration. Conclusion: our experience indicates that mitral valve repair in children with congenital mitral valve regurgitation is an effective and reliable surgical method with a low reoperation rate. A good postoperative outcome can be obtained by preoperatively recognizing the intrinsic mitral valve pathophysiology detected on echocardiography and with the well-designed, aggressive application of the various reconstruction techniques.

• Korean Journal of Plant Tissue Culture
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• v.27 no.6
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• pp.423-428
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• 2000

In 1997 when cloned sheep Dolly and soon after Polly were born, it had become head-line news because in the former the nucleus that gave rise to the lamb came from cells of six-year-old adult sheep and in the latter case a foreign gene was inserted into the donor nucleus to make the cloned sheep produce human protein, factor IX, in e milk. In the last few years, once the realm of science fiction, cloned mammals especially in livestock have become almost commonplace. What the press accounts often fail to convey, however, is that behind every success lie hundreds of failures. Many of the nuclear-transferred egg cells fail to undergo normal cell divisions. Even when an embryo does successfully implant in the womb, pregnancy often ends in miscarriage. A significant fraction of the animals that are born die shortly after birth and some of those that survived have serious developmental abnormalities. Efficiency remains at less than one % out of some hundred attempts to clone an animal. These facts show that something is fundamentally wrong and enormous hurdles must be overcome before cloning becomes practical. Cloning researchers now tent to put aside their effort to create live animals in order to probe the fundamental questions on cell biology including stem cells, the questions of whether the hereditary material in the nucleus of each cell remains intact throughout development, and how transferred nucleus is reprogrammed exactly like the zygotic nucleus. Stem cells are defined as those cells which can divide to produce a daughter cell like themselves (self-renewal) as well as a daughter cell that will give rise to specific differentiated cells (cell-differentiation). Multicellular organisms are formed from a single totipotent stem cell commonly called fertilized egg or zygote. As this cell and its progeny undergo cell divisions the potency of the stem cells in each tissue and organ become gradually restricted in the order of totipotent, pluripotent, and multipotent. The differentiation potential of multipotent stem cells in each tissue has been thought to be limited to cell lineages present in the organ from which they were derived. Recent studies, however, revealed that multipotent stem cells derived from adult tissues have much wider differentiation potential than was previously thought. These cells can differentiate into developmentally unrelated cell types, such as nerve stem cell into blood cells or muscle stem cell into brain cells. Neural stem cells isolated from the adult forebrain were recently shown to be capable of repopulating the hematopoietic system and produce blood cells in irradiated condition. In plants although the term$\boxDr$ stem cell$\boxUl$is not used, some cells in the second layer of tunica at the apical meristem of shoot, some nucellar cells surrounding the embryo sac, and initial cells of adventive buds are considered to be equivalent to the totipotent stem cells of mammals. The telomere ends of linear eukaryotic chromosomes cannot be replicated because the RNA primer at the end of a completed lagging strand cannot be replaced with DNA, causing 5' end gap. A chromosome would be shortened by the length of RNA primer with every cycle of DNA replication and cell division. Essential genes located near the ends of chromosomes would inevitably be deleted by end-shortening, thereby killing the descendants of the original cells. Telomeric DNA has an unusual sequence consisting of up to 1,000 or more tandem repeat of a simple sequence. For example, chromosome of mammal including human has the repeating telomeric sequence of TTAGGG and that of higher plant is TTTAGGG. This non-genic tandem repeat prevents the death of cell despite the continued shortening of chromosome length. In contrast with the somatic cells germ line cells have the mechanism to fill-up the 5' end gap of telomere, thus maintaining the original length of chromosome. Cem line cells exhibit active enzyme telomerase which functions to maintain the stable length of telomere. Some of the cloned animals are reported prematurely getting old. It has to be ascertained whether the multipotent stem cells in the tissues of adult mammals have the original telomeres or shortened telomeres.

• Journal of Chest Surgery
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• v.30 no.6
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• pp.598-606
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• 1997

Among 136 patients having undergone mitral valve surgery from September of 1994 through August of 1995 in Sejong Heart Institute, forty four patients(18 males, 26 females) underwent mitral valve reconstruction using prosthetic rings and their clinical results were evaluated. Patients'ages ranged from 5 to 63 years(mean age 38.2 years). Mitral valvular diseases were due to rheumatic origin in 30 patients(68%), degenerative in 13(30%), and congenital in one patient(2%). Mitral regurgitation(MR) was in 33 patients(76%), mitral stenosis 2(5%), and mitral stenoinsufaciency 9 patients(19%). The patients were divided into Carpentier's functional groups : type I, 5 patients(11%) : type I, 24 patients(55%) ; type III, 4 patients (9%) i and mixed(II + III), 11 patients(25%). Average number of anatomic lesions of mitral valve per patient was 3.7. The techniques included prosthetic ring amluloplasty(44 patients, 32 Carpentier ring and 12 Duran ring), leaflet mobilization(24, 55%), chordae shortening(23, 52%), chordae transposition(23, 52%), commissurotomy(16, 35%), leaflet resection(9, 20%), papillary muscle splitting(8, 18%), and chordae reimplantation(1, 2%). Average 3.4 surgical procedures were applied on mitral valve per patient. There were two hospital mortality and one reoperation due to development of MR(grade III) after 2 weeks. During the mean follow up of 12 months, patients improved in terms of functional class of the New York Heart Association, which was mean 3.0 preoperatively and 1.3 postoperatively. Doppler echocardiographic studies showed adequate valve area(2.07$\pm$0.11 cm2 mean $\pm$standard error), improved ventricular contractiliy in 41 patients(93%), ab ence of MR in 23(53%), trace MR in 18(42%), and garde II MR in 2 patients(5%).

• Food Science of Animal Resources
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• v.42 no.5
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• pp.816-832
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• 2022

To evaluate the effects of early postmortem vacuum packaging (VP) on meat quality during postmortem chilled storage, hot-boned lamb was vacuum-packaged at 1, 6, 12, 24, and 48 h postmortem and stored around 2℃ until 168 h postmortem, with lamb packaged in plastic wrap as the control (aerobic packaging). Intramuscular pH decline was delayed when lamb was vacuum packaged at 1, 6, and 12 h postmortem (p<0.05). The lamb vacuum-packaged at 1 h postmortem (VP-1h group) had significantly lower shear force values and purge losses accompanied by lower free thiol group values than other treatments during postmortem storage and was also higher in extractable calpain-1 activity by 6 h postmortem (p<0.05). Free thiol group concentrations were significantly higher after VP at 6 and 12 h postmortem (p<0.05). Packaging lamb under vacuum very early postmortem produced the lowest shear force and purge loss, likely by slowing heat loss and muscle temperature decline, implying that lamb quality is improved by VP when applied very early postmortem. This was at the expense of protein oxidation, which was unrelated to other meat quality measurements, most likely because potential contracture during hot boning confounded its impact. Further research is required to understand the implications of the interaction between protein oxidation, VP, and hot boning on the acceptability of lamb.

• Journal of Animal Science and Technology
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• v.46 no.1
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• pp.97-106
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• 2004

The study was conducted to investigate the effects of practical variations in feed restriction, pre-slaughter handing and chilling regime on pork quality during ageing. A total of twenty male landraces were allocated into three treatments(i.e., pre-slaughter feeding, stress and chilling regime) in a factorial arrangement. pH, temperature, free calcium ions, WB-shear force, sarcomere length, cooking loss, drip loss and objective color were determined during rigor development and/or 1, 3, 7 d postmortem. Pre-slaughter chasing stress for approximately 15 min had no effects on pH/temperature profile and objective meat quality. There was an interaction(P < 0.05) between the fasting treatment and chi1ling regime for muscle temperature at pH 6.2. Sarcomere length indicated that the current experiment conditions did not induce muscle shortening, with 1.7 to 1.8 ${\mu}m$, in spite of a significant effect of the fasting treatment (P<0.01). Pigs fed until the morning of slaughter showed a low WB-shear force(P < 0.05) until 3 d at I "C. The treatment also resulted in a higher Hunter L* and a*(P < 0.05) at 24 h and 7 d. Fasted pigs showed a significantly(P < 0.05) reduced cooking loss. The current results indicated that feeding upon the morning of slaughter became detrimental on meat color and the negative effect on cooking loss were linearly elevated with increased ageing time. On the other hand, WB-shear force did not distinguishable after 3 d. Collectively, it appeared that feed restriction from a day before slaughter could produce more a desirable meat quality at the time of consuming. However, the limited effect of animal handling and chilling rate on meat quality is not necessarily to extend to that these do not affect pork quality, as that largely depends on experimental design.

• Clinical and Experimental Pediatrics
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• v.52 no.11
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• pp.1273-1278
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• 2009

Purpose:Congenital muscular torticollis (CMT), a common musculoskeletal disorder in infants, is characterized by the rotation and flexion deformity of the neck caused by sternocleidomastoid muscle shortening. We investigated the clinical courses and perinatal risk factors of CMT. Methods:Less than 6-month-old patients (98; M:F = 60:38) diagnosed with CMT between February 2007 and August 2008 were classified into 2 clinical subgroups, namely, SMT (sternocleidomastoid tumor) and POST (postural torticollis). All the patients were physically and neurologically examined prospectively and their cervical X-rays and ultrasonographies were obtained. Their medical histories about perinatal problems were recorded. Of the 98 patients, 45 with normal range of motion were taught passive physical exercises and 43 were referred to the Department of Rehabilitation for undergoing manual stretching therapy. Results:The mean age at initial assessment was 2.2 months (SMT: $1.4{\pm}1.0$, POST: $2.7{\pm}1.6$). SMT presented earlier than POST. All ophthalmologic examinations and cervical X-rays were normal. SMT was associated with higher incidence of caput succedaneum and cephalhematoma. POST was highly associated with plagiocephaly. Mean duration of rehabilitative physical therapy was 3.7 months (SMT: $4.6{\pm}2.5$, POST: $2.6{\pm}1.9$). POST resolved earlier than SMT. Of the 88 patients with follow-up, 87 had total resolution and only 1 had residual torticollis. Conclusion:All the patients received early treatment with passive stretching exercises. CMT was associated with perinatal problems and had various risk factors such as obstetrical problems.

• Journal of Chest Surgery
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• v.35 no.10
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• pp.705-711
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• 2002

The advantages of mitral valve reconstruction have been well established and so mitral valve reconstruction is now considered as the procedure of choice to correct mitral valve disease. This is the report of intermediate-term results of 38 cases that performed mitral valve reconstruction for valve insufficiency(the total number of mitral valve reconstruction were 49 cases, but 11 cases that performed mitral valve replacement due to incomplete reconstruction were excluded). Material and Method : From March 1991 to March 2001, 38 patients underwent mitral valve repair due to mitral valve regurgitation with or without stenosis. Mean age was 47.6$\pm$14.7 years(range 15 to 70 years) : 11 were men and 27 were women. The causes of mitral valve regurgitation were degenerative in 14, rheumatic in 21, infective in 2 and the other was congenital. Result : According to the Carpentier's pathologic classification of mitral valve regurgitation, 3 were type 1 , 16 were type II and 19 were type III. Surgical procedures were annuloplasty 15, commissurotomy 19, leaflet resection and annular plication 9, chordae shortening 11, chordae transfer 5, new chordae formation 2, papillary muscle splitting 2 and vegetectomy 2. These procedures were combined in most patients. There were 2 early death and the causes of death were respiratory failure, renal failure and sepsis. There was no late death. Valve replacement was done in 6 patients after repair due to valve insufficiency or stenosis 3 weeks, 1, 3, 51, 69, 84months later respectively. These patients have been followed up from 1 to 116 months(mean 43.0 months). The mean functional class(NYHA) was 2.36 pre-operatively and improved to 1.70. Conclusion : In most cases of mitral valve regurgitation, mitral valve reconstruction when technically feasible is effective operation that can achieve stable functional results and low surgical and late mortality.