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C J Shih

Publications and source records attributed to C J Shih.

At least 19 recordsLinked to original sources
PubMed2004

Efficient phase field simulation of a binary dendritic growth in a forced flow.

Efficient quantitative phase field simulation using an adaptive finite volume method with an antisolutal trapping scheme is presented for a binary dendritic growth in a forced flow. For the case of no convection, the calculated results with different interface thickness are examined. It is found that with a proper antisolutal trapping flux, a thick interface, but smaller than the diffusion boundary layer, could be used and the solution could approach to the sharp-interface Gibbs-Thompson equation limit in almost all aspects quantitatively. Based on the concentration driving force obtained from the sharp-interface limit of the Wheeler-Boettinger-McFadden (WBM) model, the calculated results are in good agreement with the classic Oseen-Ivantsov solution for the concentration-driven growth in a forced flow. And the selection scaling factor also increases with the external flow as the theoretical prediction.

Journal Article↗
PubMed2001

Characterization of Methanococcus voltaei strain P2F9701a: a new methanogen isolated from estuarine environment.

A new methanogen, designated as strain P2F9701a (= OCM 745), was isolated from a water sample of estuarine environment in Elrin Shi, Taiwan. Cells of strain P2F9701a were motile coccus (0.7 approximately 1.1 micron) with tufts of flagella. Gas vacuoles were observed, and the protein cell wall was composed of S-layer protein subunit with Mr of 74,700. Cells catabolized formate and H2+CO2 to produce methane, but not acetate, methanol, and trimethylamine. Strain P2F9701a grew in the range of 30-42 degrees C, with optimal growth temperature at 37 degrees C, but did not grow below 28 degrees C or above 42 degrees C. This estuarine isolate P2F9701a tolerated well the NaCl concentration between 0.02 and 1.03 m, and the optimal salt for growth was 0.17 m. Although phylogenetic analytic results indicated that P2F9701a belongs to the mesophilic, hydrogenotrophic marine methanogen of Methanococcus voltaei, the occurrence of gas vacuoles, tufts of flagella, eury-halotolerant and steno-thermotolerant characters of strain P2F9701a are different from mesophilic Methanococcus spp. that had been reported.

Hydrogen↗
PubMed1999

Acute and chronic phase platelet aggregability studies in Chinese patients after implantation of a permanent transvenous pacemaker.

It has been suggested that the incidence of thromboembolic events always increases in patients after insertion of a transvenous pacemaker. Blood samples from twenty consecutive patients (fifteen males and five females) before and after pacemaker implantation was retained for platelet aggregability studies which were analyzed separately with ADP, collagen, epinephrine and arachidonic acid. The maximal amplitude of platelet aggregatory curve was detected by an aggregometer. The samples collected the day before pacemaker implantation (day 0) were used as self-control. Day 1 and day 3 after pacemaker implantation were defined as the acute phase, while day 30 was defined as the chronic phase. The maximal amplitude of platelet aggregatory curve was observed to be lowest on day 1 and then return to normal on day 3 and day 30. The results of platelet aggregability, however, showed no significant difference (P>0.05) between self-control and post-implantation samples. In conclusion, there was no significant change in platelet aggregability for either acute or chronic phases after pacemaker implantation. Antiplatelet medications may not be necessary for the prevention of thromboembolic events after the implantation of a pacemaker.

Aged↗
PubMed1998

Distinct biochemical and topological properties of the 31- and 27-kilodalton plasma membrane intrinsic protein subgroups from red beet.

Plasma membrane vesicles from red beet (Beta vulgaris L.) storage tissue contain two prominent major intrinsic protein species of 31 and 27 kD (X. Qi, C.Y Tai, B.P. Wasserman [1995] Plant Physiol 108: 387-392). In this study affinity-purified antibodies were used to investigate their localization and biochemical properties. Both plasma membrane intrinsic protein (PMIP) subgroups partitioned identically in sucrose gradients; however, each exhibited distinct properties when probed for multimer formation, and by limited proteolysis. The tendency of each PMIP species to form disulfide-linked aggregates was studied by inclusion of various sulfhydryl agents during tissue homogenization and vesicle isolation. In the absence of dithiothreitol and sulfhydryl reagents, PMIP27 yielded a mixture of monomeric and aggregated species. In contrast, generation of a monomeric species of PMIP31 required the addition of dithiothreitol, iodoacetic acid, or N-ethylmaleimide. Mixed disulfide-linked heterodimers between the PMIP31 and PMIP27 subgroups were not detected. Based on vectorial proteolysis of right-side-out vesicles with trypsin and hydropathy analysis of the predicted amino acid sequence derived from the gene encoding PMIP27, a topological model for a PMIP27 was established. Two exposed tryptic cleavage sites were identified from proteolysis of PMIP27, and each was distinct from the single exposed site previously identified in surface loop C of a PMIP31. Although the PMIP31 and PMIP27 species both contain integral proteins that appear to occur within a single vesicle population, these results demonstrate that each PMIP subgroup responds differently to perturbations of the membrane.

Amino Acid Sequence↗
PubMed1997

Establishment of a cell line from Spodoptera litura (Lepidoptera: Noctuidae) and replication of S. litura nuclear polyhedrosis virus in vitro.

A new cell line, designated IBL-SLO1A, was established from pupal ovaries of the tobacco cutworm Spodoptera litura. Cells were grown in the TNM-FH insect cell culture medium supplemented with 10% fetal bovine serum. The subculture of cells was initiated with 1-3 x 10(5) cells/ml, a split ratio about 1:10. The growth curve of the cells fit the model of exponential growth (Y = e-0.6750 + 0.0317X R2 = 0. 98), the population doubling time during logarithmic growth at 28 degrees C was 21.9 hr. The number of chromosomes was about 140. Cytopathology characteristics of baculovirus infection were observed when the culture cells were infected with SINPV derived from alkali dissolution of occlusion bodies at 24 hr postinfection (pi). The cells lysed and released occlusion bodies into culture medium at 120 hr pi.

Animals↗
PubMed1997

Epidemiological study of moyamoya disease in Taiwan.

From January 1978 to December 1995, 92 cases of Moyamoya disease were collected from seven major medical centers in Taiwan. The data gave an annual incidence rate of 0.048 per 100,000 population. There were 40 males and 52 females and the ages ranged from 2 to 62 years with the peak incidence in the 31-40 year age group (23 cases). Cerebral infarction occurred in 20 out of 24 juvenile patients (83%), and in 24 out of 68 adult patients (35%). The difference was statistically significant. Haemorrhagic stroke was more frequent in adult patients. Computed tomographic scans following stroke showed cerebral infarction in 44 cases, ventricular haemorrhage in 26 cases, intracerebral haemorrhage in 14 cases and pure subarachnoid haemorrhage in eight. The most frequent initial symptom was motor disturbance (59%), followed by headache (49%) and impaired consciousness (35%). This survey showed an incidence rate much lower than that in Japan, but comparable with those in other Oriental countries and higher than those in Western countries. The male-to-female ratio once differed considerably from that of the Japanese series, but from the present study is now quite similar.

Adolescent↗
PubMed1996

Contralateral temperature changes of the finger surface during video endoscopic sympathectomy for palmar hyperhidrosis.

One hundred and eight consecutive patients with primary palmar hyperhidrosis were surgically managed by coagulation of bilateral T2 sympathetic ganglia using video thoracoscopic techniques. Patients were divided into two groups. In the first group (N = 46), finger surface temperature of the ipsilateral index finger was recorded before and after T2 ganglionectomy. The average increase of post-operative temperature was 2.74 +/- 0.27 degrees C (mean +/- SE) on the right side and 2.67 +/- 0.33 degrees C on the left (P < 0.05). The significant rise of temperature resulting from sympatholytic vasodilatation was only noted in cases of exact ablation of the T2 ganglion. In the second group (N = 62), surface temperatures of both index fingers were monitored and recorded simultaneously. These patients were arbitrarily subdivided into Group 2-A (N = 29) when right side ganglionectomy was performed first and Group 2-B (N = 33) when left side ganglionectomy was done initially. After the first ganglionectomy was completed, an ipsilateral increase with a contralateral decrease of temperature was observed; the average increase of temperature was 1.92 +/- 0.35 degrees C and 2.19 +/- 0.30 degrees C, and the average decrease was 1.50 +/- 0.51 degrees C and 1.67 +/- 0.39 degrees C for Group 2-A and 2-B respectively (P < 0.05). The authors postulate that a cross-inhibitory effect by the post-ganglionic neurons innervating blood vessels of the upper extremities may exists in humans and this effect is released after ganglionectomy, resulting in contralateral vasoconstriction and decrease of finger surface temperature.

Adolescent↗
PubMed1996

Risk factors predicting surgically significant intracranial hematomas in patients with head injuries.

This population-based study was designed to determine the risk of patients with head injuries to develop surgically significant intracranial hematomas (SSIHs). A total of 28,500 cases of head injury were reviewed in Taipei City and Hualien County from 1988 to 1992. The Glasgow Coma Scale (GCS) was used to determine the severity of head injury. The presence of skull fracture and intracranial hematoma was determined by x-ray and computed tomographic (CT) scan, respectively. Those patients suffering from both loss of consciousness and skull fracture had a significantly greater risk of developing SSIHs than those having none or only one of these conditions. The relationship between skull fracture and severity of head injury revealed that the presence of a skull fracture in mildly head-injured patients could be used as an indicator to investigate the development of SSIHs before the occurrence of irreversible damage. The distribution of hematomas by location showed that a higher rate of SSIH resulting in parenchymal damage occurred when consciousness was lost. It also showed that epidural hematomas occurred more frequently with skull fractures. Skull fracture and impaired consciousness are important indices in determining the risk of developing SSIH.

Adult↗
PubMed1994

[Moyamoya disease in Taiwan].

From January 1978 to December 1993, 73 patients with moyamoya disease were collected from seven neurological centers in Taiwan. The annual incidence of this disease in Taiwan is 0.024 per 100,000 population. There were 33 males and 40 females. The ages ranged from 2 to 62 years with a peak incidence in the 31 to 40 year age group (18 cases). Cerebral infarction occurred in 16 out of 19 juvenile patients (84.2%); by contrast, only 19 out of 54 adult patients (35.2%) presented with infarction. Hemorrhagic strokes were more frequent in adult patients. Computed tomographic scans following stroke showed cerebral infarction in 35 cases, ventricular hemorrhage in 21 cases, intracerebral hemorrhage in 11 cases and pure subarachnoidal hemorrhage in 6 cases. The most frequent initial symptom was motor disturbance (58.9%), followed by headaches (49.3%), and impaired consciousness (34.2%). Compared with reports from Japan, this survey showed a lower incidence of moyamoya disease in Taiwan.

Adolescent↗
PubMed1993

[Intracranial arteriovenous malformations in Taiwan].

This paper analyzes the available literature on intracranial arteriovenous malformations (AVM) in Taiwan. The incidence and symptoms of the disease are studied with a view to assisting practitioners in its recognition. The incidence of intracranial AVM in patients who have suffered hemorrhagic stroke in Taiwan is 2.5% to 4.8%, with the male to female ratio being 1.5:1. The peak age at which bleeding from intracranial AVM occurred ranged from 10 to 40 years; bleeding showed no seasonal variation. Sudden headaches, vomiting, and disturbance of consciousness were the commonest presenting symptoms of AVM, similar to the rupture of intracranial aneurysms. However, the possibility of focal neurological deficit among patients with intracranial AVM was higher than in patients with intracranial aneurysms. Risk factors, such as hypertension, diabetes mellitus, heart disease, smoking and alcohol intake showed no close relationship to bleeding in intracranial AVM. Pregnancy is not a risk factor in female patients with intracranial AVM with no history of hemorrhage. Small intracranial AVM are more likely to bleed. Since 1961 the majority of Taiwan's intracranial AVM patients have been treated surgically, while before that date general medicine was the treatment of choice. In recent years, several developments such as operation microscope, microsurgical instruments and microsurgical techniques have enhanced the efficacy of surgical intervention in the treatment of AVM. When the mortality and morbidity rates resulting from the two forms of treatment are compared, surgical treatment shows a better prognosis for the treatment of intracranial AVM.

Adolescent↗
PubMed1993

Neurobehavioral manifestations following closed head injury.

This study was designed to examine neurobehavioral sequelae following closed head injuries. It adapted the Neurobehavioral Rating Scale (NRS) which was designed by Harvey S. Levin in 1987. The scale has been proven to be valid and reliable in previous Western studies and was translated by the authors into Mandarin with the consent of its designer. A total of 335 cases of closed head injury in eight major hospitals in Taipei were studied. The main findings obtained from this preliminary study were: 1) the correlation coefficients between raters ranged from 0.749 to 0.956, manifesting satisfactory reliability; 2) seven factors were obtained through factorial analysis of NRS, explaining 65.5% of the variance; and 3) significant differences in neurobehavioral change were found in patients with various degrees of severity and various types of head injuries. The results demonstrate that NRS is applicable to Chinese patients. Possible modification as well as elaboration of this scale is suggested.

Analysis of Variance↗
PubMed1992

[Epidemiologic study of head injuries in Taipei City, Taiwan].

This study was designed to examine the descriptive epidemiology of head injuries in an urban population in the Taiwan area, Taipei City, during the period from July 1, 1987 to June 30, 1988. Clinical records reviewed included emergency room (ER) charts, inpatient charts of 19 major hospitals, death registration forms and medical examiners' reports in this city. A formulated definition was used to identify patients with head injuries. A total of 4,692 cases were collected, which included 4,319 hospital inpatients and 373 non-hospital deaths. The average incidence rate for head injury was 180/100,000 per year, 246/100,000 for males and 111/100,000 for females. The highest incidence rate was observed in the elderly group followed by the age group of 20-29 years. Sixty eight percent of the head injuries were caused by traffic accidents, 59.7 percent of which were involved in motorcycle rides. This rate was higher than those in any western reports. Among the 10-39 age group, the head injuries caused by traffic accidents were mainly due to motorcycle accidents. However, most of the children and the elderly who were injured were either pedestrians or bicycle riders. The average mortality rate was 23/100,000 per year, 34/100,000 for males and 12/100,000 for females. Initially the Glasgow Coma Scale was used in assessing the severity of head injuries. Seventy-two percent of the cases were considered mild, and 28 percent moderate to severe in degree, including 609 deaths.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1991

[An epidemiological study of head injury in Hualien County, Taiwan].

An epidemiological study of head injuries in Hualien County, Taiwan, was undertaken from July 1, 1987 to June 30, 1988. Clinical records, including emergency room (ER) charts, inpatient charts from the four major hospitals and coroner or medical examiner reports in this county, were reviewed. A formulated definition was used in identifying patients with head injury. A total of 1,183 cases were identified. They included 975 hospital inpatients and 208 nonhospital deaths. The age-adjusted incidence rate for head injuries was 333/100,000 for all, 450/100,000 for males and 194/100,000 for females, with a male-to-female ratio of 2.32. The cumulative incidence rate from 0 to 69 years of age was 27.6% for males and 13.7% for females. The highest incidence rate was observed in the elderly group, whereas in other published reports the highest occurrence has been noted in the young adult group. An extraordinary 82% of the head injuries were associated with traffic accidents, 71% of which directly involved motorcycle riders. The age-adjusted mortality rate was 89/100,000 per year, 127/100,000 for males and 44/100,000 for females. The cumulative mortality rate was 8.7% for males and 3.2% for females. These are the highest rates ever reported. Sixty percent of the 1,183 patients had a moderate to severe injury or were dead. In the remaining 40%, the injury was considered mild. The elderly group presented with the highest percentage of moderate to severe degrees of injury, as well as mortality. Among traffic accident victims, those from motorcycle accidents and pedestrians had the highest percentage of severe head injuries.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1989

Influence of thermal stress and various agents on the brain edema formation in rats following a cryogenic brain lesion.

The influence of cold stress, heat stress, or various agents on the development of brain edema were assessed in rats following a cryogenic brain lesion. Brain edema was induced by local cold injury to the cortex. Cerebral edema was assessed 0.5, 3.0 or 24 h after a cryogenic brain lesion by measuring the water content of two hemispheres. Pretreatment of animals with sodium pentobarbital (15 or 30 mg/kg, i.p.) or lidocaine (15 mg/kg, i.p.) did not influence the development of brain edema. In addition, pretreatment with an external heat stress (heat exposure of 32 degrees C for 6 h) exaggerated significantly the development of brain edema in the rat following a cryogenic brain lesion. On the other hand, pretreatment of animals with either external cold stress (cold exposure of 8 degrees C for 6 h), glycerol (10% 10 ml, i.p.), mannitol (15% 10 ml, i.p.), gamma-hydroxybutyric acid (300 mg/kg, i.p.), metiamide (5 mg/kg, i.p.), dexamethasone (4 mg/kg, i.p.), aminophylline (100 mg/kg, i.p.), or ketamine (30 mg/kg, i.p.) inhibited significantly the brain edema formation.

Animals↗
PubMed1988

Sympathetic postganglionic innervation of the cardiac coronary artery in cats.

The localization of the sympathetic postganglionic neurons innervating the cardiac coronary arteries of the cat was investigated using retrograde axonal transport with horseradish peroxidase. We found after the enzyme was applied to the main trunk of the right coronary artery, and to the main trunk and the terminal branch of the ventral descending vessels of the left coronary artery, the peroxidase-labeled sympathetic neurons were localized predominantly in the right stellate ganglia, with a few cells in the left stellate ganglia. There were very few labeled cells in the middle cervical, superior cervical, and T4-7 ganglia on both sides. After peroxidase application to the terminal branch of the dorsal descending vessels of the right coronary artery, labeled cells were mainly in the left stellate ganglia, with only a few cells in the right stellate ganglia.

Animals↗
PubMed1987

Involvement of both opiate and catecholaminergic receptors of ventromedial hypothalamus in the locomotor stimulant action of thyrotropin-releasing hormone.

To explore the mode of the locomotor stimulant action of thyrotropin-releasing hormone (TRH), rats with or without administration of opiate or catecholaminergic receptor antagonists were infused with TRH through previously implanted hypothalamic cannula. Administration of TRH, but not the normal saline or TSH, into the ventromedial hypothalamus caused an enhancement in both the gross movements (including stimulation of forward locomotion, head and body rearing) and fine movements (including increased grooming and head swaying). The locomotor stimulant action provoked by TRH was antagonized by pretreatment of ventromedial hypothalamus with either an alpha-adrenergic receptor antagonist (yohimbine), a dopaminergic receptor antagonist (haloperidol) or an opiate receptor antagonist (naloxone), but not with a beta-adrenergic receptor antagonist (propranolol). The results indicate that all the adrenergic, dopaminergic and opiate receptors in the ventromedial hypothalamus are involved in the TRH-induced hyperactivity in the rat.

Animals↗
PubMed1987

Bombesin-induced hypothermia: possible involvement of cholinergic and dopaminergic receptors in the rat hypothalamus.

The thermal responses of rats which were pretreated with 5,7-dihydroxytryptamine to deplete hypothalamic 5-hydroxytryptamine, 6-hydroxydopamine to deplete hypothalamic catecholamines, phentolamine and propranolol to inhibit adrenergic receptors, haloperidol to inhibit dopamine receptors, or atropine to inhibit cholinergic receptors, to intrahypothalamic administration of bombesin were compared with those of control rats. The bombesin-induced hypothermia was attenuated by pretreatment of the rats with either hypothalamic dopamine depletion or receptor blockade, or hypothalamic cholinergic receptor blockade. The reduction in the bombesin-induced hypothermia in the treated rats was due to the reduction of metabolic and vasomotor response. The data indicate that bombesin may act on hypothalamic dopamine and/or cholinergic receptor mechanisms to induce hypothermia by promoting a reduction in metabolic heat production and an enhancement in heat loss in rats.

Animals↗